text: /* Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #include "apr.h"
  #include "apr_strings.h"
  #include "apr_lib.h"
  #include "apr_fnmatch.h"
  #include "apr_hash.h"
  #include "apr_thread_proc.h"    /* for RLIMIT stuff */
  #include "apr_random.h"
  
  #include "apr_version.h"
  #if APR_MAJOR_VERSION < 2
  #include "apu_version.h"
  #endif
  
  #define APR_WANT_IOVEC
  #define APR_WANT_STRFUNC
  #define APR_WANT_MEMFUNC
  #include "apr_want.h"
  
  #include "ap_config.h"
  #include "httpd.h"
  #include "http_config.h"
  #include "http_core.h"
  #include "http_protocol.h" /* For index_of_response().  Grump. */
  #include "http_request.h"
  #include "http_vhost.h"
  #include "http_main.h"     /* For the default_handler below... */
  #include "http_log.h"
  #include "http_connection.h"
  #include "apr_buckets.h"
  #include "util_filter.h"
  #include "util_ebcdic.h"
  #include "util_mutex.h"
  #include "util_time.h"
  #include "mpm_common.h"
  #include "scoreboard.h"
  #include "mod_core.h"
  #include "mod_proxy.h"
  #include "ap_listen.h"
  #include "ap_provider.h"
  #include "ap_regex.h"
  #include "core.h"
  
  #include "mod_so.h" /* for ap_find_loaded_module_symbol */
  
  #if defined(RLIMIT_CPU) || defined (RLIMIT_DATA) || defined (RLIMIT_VMEM) || defined(RLIMIT_AS) || defined (RLIMIT_NPROC)
  #include "unixd.h"
  #endif
  #if APR_HAVE_UNISTD_H
  #include <unistd.h>
  #endif
  
  /* LimitRequestBody handling */
  #define AP_LIMIT_REQ_BODY_UNSET         ((apr_off_t) -1)
  #define AP_DEFAULT_LIMIT_REQ_BODY       ((apr_off_t) 0)
  
  /* LimitXMLRequestBody handling */
  #define AP_LIMIT_UNSET                  ((long) -1)
  #define AP_DEFAULT_LIMIT_XML_BODY       ((apr_size_t)1000000)
  
  #define AP_MIN_SENDFILE_BYTES           (256)
  
  /* maximum include nesting level */
  #ifndef AP_MAX_INCLUDE_DEPTH
  #define AP_MAX_INCLUDE_DEPTH            (128)
  #endif
  
  /* valid in core-conf, but not in runtime r->used_path_info */
  #define AP_ACCEPT_PATHINFO_UNSET 3
  
  #define AP_FLUSH_MAX_THRESHOLD 65535
  #define AP_FLUSH_MAX_PIPELINED 4
  
  APR_HOOK_STRUCT(
      APR_HOOK_LINK(get_mgmt_items)
      APR_HOOK_LINK(insert_network_bucket)
  )
  
  AP_IMPLEMENT_HOOK_RUN_ALL(int, get_mgmt_items,
                            (apr_pool_t *p, const char *val, apr_hash_t *ht),
                            (p, val, ht), OK, DECLINED)
  
  AP_IMPLEMENT_HOOK_RUN_FIRST(apr_status_t, insert_network_bucket,
                              (conn_rec *c, apr_bucket_brigade *bb,
                               apr_socket_t *socket),
                              (c, bb, socket), AP_DECLINED)
  
  /* Server core module... This module provides support for really basic
   * server operations, including options and commands which control the
   * operation of other modules.  Consider this the bureaucracy module.
   *
   * The core module also defines handlers, etc., to handle just enough
   * to allow a server with the core module ONLY to actually serve documents.
   *
   * This file could almost be mod_core.c, except for the stuff which affects
   * the http_conf_globals.
   */
  
  /* we know core's module_index is 0 */
  #undef APLOG_MODULE_INDEX
  #define APLOG_MODULE_INDEX AP_CORE_MODULE_INDEX
  
  /* Handles for core filters */
  AP_DECLARE_DATA ap_filter_rec_t *ap_subreq_core_filter_handle;
  AP_DECLARE_DATA ap_filter_rec_t *ap_core_output_filter_handle;
  AP_DECLARE_DATA ap_filter_rec_t *ap_content_length_filter_handle;
  AP_DECLARE_DATA ap_filter_rec_t *ap_core_input_filter_handle;
  
  /* Provide ap_document_root_check storage and default value = true */
  AP_DECLARE_DATA int ap_document_root_check = 1;
  
  /* magic pointer for ErrorDocument xxx "default" */
  static char errordocument_default;
  
  /* Global state allocated out of pconf: variables here MUST be
   * cleared/reset in reset_config(), a pconf cleanup, to avoid the
   * variable getting reused after the pool is cleared. */
  static apr_array_header_t *saved_server_config_defines = NULL;
  static apr_table_t *server_config_defined_vars = NULL;
  AP_DECLARE_DATA const char *ap_runtime_dir = NULL;
  static const char *core_state_dir;
  
  AP_DECLARE_DATA int ap_main_state = AP_SQ_MS_INITIAL_STARTUP;
  AP_DECLARE_DATA int ap_run_mode = AP_SQ_RM_UNKNOWN;
  AP_DECLARE_DATA int ap_config_generation = 0;
  
  typedef struct {
      apr_ipsubnet_t *subnet;
      struct ap_logconf log;
  } conn_log_config;
  
  static void *create_core_dir_config(apr_pool_t *a, char *dir)
  {
      core_dir_config *conf;
  
      conf = (core_dir_config *)apr_pcalloc(a, sizeof(core_dir_config));
  
      /* conf->r and conf->d[_*] are initialized by dirsection() or left NULL */
  
      conf->opts = dir ? OPT_UNSET : OPT_UNSET|OPT_SYM_LINKS;
      conf->opts_add = conf->opts_remove = OPT_NONE;
      conf->override = OR_UNSET|OR_NONE;
      conf->override_opts = OPT_UNSET | OPT_ALL | OPT_SYM_OWNER | OPT_MULTI;
  
      conf->accept_path_info = AP_ACCEPT_PATHINFO_UNSET;
  
      conf->use_canonical_name = USE_CANONICAL_NAME_UNSET;
      conf->use_canonical_phys_port = USE_CANONICAL_PHYS_PORT_UNSET;
  
      conf->hostname_lookups = HOSTNAME_LOOKUP_UNSET;
  
      /*
       * left as NULL (we use apr_pcalloc):
       * conf->limit_cpu = NULL;
       * conf->limit_mem = NULL;
       * conf->limit_nproc = NULL;
       * conf->sec_file = NULL;
       * conf->sec_if   = NULL;
       */
  
      conf->limit_req_body = AP_LIMIT_REQ_BODY_UNSET;
      conf->limit_xml_body = AP_LIMIT_UNSET;
  
      conf->server_signature = srv_sig_unset;
  
      conf->add_default_charset = ADD_DEFAULT_CHARSET_UNSET;
      conf->add_default_charset_name = DEFAULT_ADD_DEFAULT_CHARSET_NAME;
  
      /* Overriding all negotiation
       * Set NULL by apr_pcalloc:
       * conf->mime_type = NULL;
       * conf->handler = NULL;
       * conf->output_filters = NULL;
       * conf->input_filters = NULL;
       */
  
      /*
       * Flag for use of inodes in ETags.
       */
      conf->etag_bits = ETAG_UNSET;
      conf->etag_add = ETAG_UNSET;
      conf->etag_remove = ETAG_UNSET;
  
      conf->enable_mmap = ENABLE_MMAP_UNSET;
      conf->enable_sendfile = ENABLE_SENDFILE_UNSET;
      conf->allow_encoded_slashes = 0;
      conf->decode_encoded_slashes = 0;
  
      conf->max_ranges = AP_MAXRANGES_UNSET;
      conf->max_overlaps = AP_MAXRANGES_UNSET;
      conf->max_reversals = AP_MAXRANGES_UNSET;
  
      conf->cgi_pass_auth = AP_CGI_PASS_AUTH_UNSET;
      conf->qualify_redirect_url = AP_CORE_CONFIG_UNSET; 
  
      return (void *)conf;
  }
  
  static void *merge_core_dir_configs(apr_pool_t *a, void *basev, void *newv)
  {
      core_dir_config *base = (core_dir_config *)basev;
      core_dir_config *new = (core_dir_config *)newv;
      core_dir_config *conf;
  
      /* Create this conf by duplicating the base, replacing elements
       * (or creating copies for merging) where new-> values exist.
       */
      conf = (core_dir_config *)apr_pmemdup(a, base, sizeof(core_dir_config));
  
      conf->d = new->d;
      conf->d_is_fnmatch = new->d_is_fnmatch;
      conf->d_components = new->d_components;
      conf->r = new->r;
      conf->refs = new->refs;
      conf->condition = new->condition;
  
      if (new->opts & OPT_UNSET) {
          /* there was no explicit setting of new->opts, so we merge
           * preserve the invariant (opts_add & opts_remove) == 0
           */
          conf->opts_add = (conf->opts_add & ~new->opts_remove) | new->opts_add;
          conf->opts_remove = (conf->opts_remove & ~new->opts_add)
                              | new->opts_remove;
          conf->opts = (conf->opts & ~conf->opts_remove) | conf->opts_add;
  
          /* If Includes was enabled with exec in the base config, but
           * was enabled without exec in the new config, then disable
           * exec in the merged set. */
          if (((base->opts & (OPT_INCLUDES|OPT_INC_WITH_EXEC))
               == (OPT_INCLUDES|OPT_INC_WITH_EXEC))
              && ((new->opts & (OPT_INCLUDES|OPT_INC_WITH_EXEC))
                  == OPT_INCLUDES)) {
              conf->opts &= ~OPT_INC_WITH_EXEC;
          }
      }
      else {
          /* otherwise we just copy, because an explicit opts setting
           * overrides all earlier +/- modifiers
           */
          conf->opts = new->opts;
          conf->opts_add = new->opts_add;
          conf->opts_remove = new->opts_remove;
      }
  
      if (!(new->override & OR_UNSET)) {
          conf->override = new->override;
      }
  
      if (!(new->override_opts & OPT_UNSET)) {
          conf->override_opts = new->override_opts;
      }
  
      if (new->override_list != NULL) {
          conf->override_list = new->override_list;
      }
  
      if (conf->response_code_exprs == NULL) {
          conf->response_code_exprs = new->response_code_exprs;
      }
      else if (new->response_code_exprs != NULL) {
          conf->response_code_exprs = apr_hash_overlay(a,
                  new->response_code_exprs, conf->response_code_exprs);
      }
      /* Otherwise we simply use the base->response_code_exprs array
       */
  
      if (new->hostname_lookups != HOSTNAME_LOOKUP_UNSET) {
          conf->hostname_lookups = new->hostname_lookups;
      }
  
      if (new->accept_path_info != AP_ACCEPT_PATHINFO_UNSET) {
          conf->accept_path_info = new->accept_path_info;
      }
  
      if (new->use_canonical_name != USE_CANONICAL_NAME_UNSET) {
          conf->use_canonical_name = new->use_canonical_name;
      }
  
      if (new->use_canonical_phys_port != USE_CANONICAL_PHYS_PORT_UNSET) {
          conf->use_canonical_phys_port = new->use_canonical_phys_port;
      }
  
  #ifdef RLIMIT_CPU
      if (new->limit_cpu) {
          conf->limit_cpu = new->limit_cpu;
      }
  #endif
  
  #if defined(RLIMIT_DATA) || defined(RLIMIT_VMEM) || defined(RLIMIT_AS)
      if (new->limit_mem) {
          conf->limit_mem = new->limit_mem;
      }
  #endif
  
  #ifdef RLIMIT_NPROC
      if (new->limit_nproc) {
          conf->limit_nproc = new->limit_nproc;
      }
  #endif
  
      if (new->limit_req_body != AP_LIMIT_REQ_BODY_UNSET) {
          conf->limit_req_body = new->limit_req_body;
      }
  
      if (new->limit_xml_body != AP_LIMIT_UNSET)
          conf->limit_xml_body = new->limit_xml_body;
  
      if (!conf->sec_file) {
          conf->sec_file = new->sec_file;
      }
      else if (new->sec_file) {
          /* If we merge, the merge-result must have its own array
           */
          conf->sec_file = apr_array_append(a, base->sec_file, new->sec_file);
      }
      /* Otherwise we simply use the base->sec_file array
       */
  
      if (!conf->sec_if) {
          conf->sec_if = new->sec_if;
      }
      else if (new->sec_if) {
          /* If we merge, the merge-result must have its own array
           */
          conf->sec_if = apr_array_append(a, base->sec_if, new->sec_if);
      }
      /* Otherwise we simply use the base->sec_if array
       */
  
      if (new->server_signature != srv_sig_unset) {
          conf->server_signature = new->server_signature;
      }
  
      if (new->add_default_charset != ADD_DEFAULT_CHARSET_UNSET) {
          conf->add_default_charset = new->add_default_charset;
          conf->add_default_charset_name = new->add_default_charset_name;
      }
  
      /* Overriding all negotiation
       */
      if (new->mime_type) {
          conf->mime_type = new->mime_type;
      }
  
      if (new->handler) {
          conf->handler = new->handler;
      }
      if (new->expr_handler) {
          conf->expr_handler = new->expr_handler;
      }
  
      if (new->output_filters) {
          conf->output_filters = new->output_filters;
      }
  
      if (new->input_filters) {
          conf->input_filters = new->input_filters;
      }
  
      /*
       * Now merge the setting of the FileETag directive.
       */
      if (new->etag_bits == ETAG_UNSET) {
          conf->etag_add =
              (conf->etag_add & (~ new->etag_remove)) | new->etag_add;
          conf->etag_remove =
              (conf->etag_remove & (~ new->etag_add)) | new->etag_remove;
          conf->etag_bits =
              (conf->etag_bits & (~ conf->etag_remove)) | conf->etag_add;
      }
      else {
          conf->etag_bits = new->etag_bits;
          conf->etag_add = new->etag_add;
          conf->etag_remove = new->etag_remove;
      }
  
      if (conf->etag_bits != ETAG_NONE) {
          conf->etag_bits &= (~ ETAG_NONE);
      }
  
      if (new->enable_mmap != ENABLE_MMAP_UNSET) {
          conf->enable_mmap = new->enable_mmap;
      }
  
      if (new->enable_sendfile != ENABLE_SENDFILE_UNSET) {
          conf->enable_sendfile = new->enable_sendfile;
      }
   
      if (new->read_buf_size) {
          conf->read_buf_size = new->read_buf_size;
      }
      else {
          conf->read_buf_size = base->read_buf_size;
      }
  
      if (new->allow_encoded_slashes_set) {
          conf->allow_encoded_slashes = new->allow_encoded_slashes;
      }
      if (new->decode_encoded_slashes_set) {
          conf->decode_encoded_slashes = new->decode_encoded_slashes;
      }
  
      if (new->log) {
          if (!conf->log) {
              conf->log = new->log;
          }
          else {
              conf->log = ap_new_log_config(a, new->log);
              ap_merge_log_config(base->log, conf->log);
          }
      }
  
      conf->max_ranges = new->max_ranges != AP_MAXRANGES_UNSET ? new->max_ranges : base->max_ranges;
      conf->max_overlaps = new->max_overlaps != AP_MAXRANGES_UNSET ? new->max_overlaps : base->max_overlaps;
      conf->max_reversals = new->max_reversals != AP_MAXRANGES_UNSET ? new->max_reversals : base->max_reversals;
  
      conf->cgi_pass_auth = new->cgi_pass_auth != AP_CGI_PASS_AUTH_UNSET ? new->cgi_pass_auth : base->cgi_pass_auth;
  
      if (new->cgi_var_rules) {
          if (!conf->cgi_var_rules) {
              conf->cgi_var_rules = new->cgi_var_rules;
          }
          else {
              conf->cgi_var_rules = apr_hash_overlay(a, new->cgi_var_rules, conf->cgi_var_rules);
          }
      }
  
      AP_CORE_MERGE_FLAG(qualify_redirect_url, conf, base, new);
  
      return (void*)conf;
  }
  
  #if APR_HAS_SO_ACCEPTFILTER
  #ifndef ACCEPT_FILTER_NAME
  #define ACCEPT_FILTER_NAME "httpready"
  #ifdef __FreeBSD_version
  #if __FreeBSD_version < 411000 /* httpready broken before 4.1.1 */
  #undef ACCEPT_FILTER_NAME
  #define ACCEPT_FILTER_NAME "dataready"
  #endif
  #endif
  #endif
  #endif
  
  static void *create_core_server_config(apr_pool_t *a, server_rec *s)
  {
      core_server_config *conf;
      int is_virtual = s->is_virtual;
  
      conf = (core_server_config *)apr_pcalloc(a, sizeof(core_server_config));
  
      /* global-default / global-only settings */
  
      if (!is_virtual) {
          conf->ap_document_root = DOCUMENT_LOCATION;
          conf->access_name = DEFAULT_ACCESS_FNAME;
  
          /* A mapping only makes sense in the global context */
          conf->accf_map = apr_table_make(a, 5);
  #if APR_HAS_SO_ACCEPTFILTER
          apr_table_setn(conf->accf_map, "http", ACCEPT_FILTER_NAME);
          apr_table_setn(conf->accf_map, "https", "dataready");
  #elif defined(WIN32)
          /* 'data' is disabled on Windows due to a DoS vuln (PR 59970) */
          apr_table_setn(conf->accf_map, "http", "connect");
          apr_table_setn(conf->accf_map, "https", "connect");
  #else
          apr_table_setn(conf->accf_map, "http", "data");
          apr_table_setn(conf->accf_map, "https", "data");
  #endif
  
          conf->flush_max_threshold = AP_FLUSH_MAX_THRESHOLD;
          conf->flush_max_pipelined = AP_FLUSH_MAX_PIPELINED;
      }
      else {
          conf->flush_max_pipelined = -1;
      }
  
      /* initialization, no special case for global context */
  
      conf->sec_dir = apr_array_make(a, 40, sizeof(ap_conf_vector_t *));
      conf->sec_url = apr_array_make(a, 40, sizeof(ap_conf_vector_t *));
  
      /* pcalloc'ed - we have NULL's/0's
      conf->gprof_dir = NULL;
  
      ** recursion stopper; 0 == unset
      conf->redirect_limit = 0;
      conf->subreq_limit = 0;
  
      conf->protocol = NULL;
       */
  
      conf->trace_enable = AP_TRACE_UNSET;
  
      conf->protocols = apr_array_make(a, 5, sizeof(const char *));
      conf->protocols_honor_order = -1;
      conf->async_filter = 0;
      conf->strict_host_check= AP_CORE_CONFIG_UNSET; 
      conf->merge_slashes    = AP_CORE_CONFIG_UNSET; 
  
      return (void *)conf;
  }
  
  static void *merge_core_server_configs(apr_pool_t *p, void *basev, void *virtv)
  {
      core_server_config *base = (core_server_config *)basev;
      core_server_config *virt = (core_server_config *)virtv;
      core_server_config *conf = (core_server_config *)
                                 apr_pmemdup(p, base, sizeof(core_server_config));
  
      if (virt->ap_document_root)
          conf->ap_document_root = virt->ap_document_root;
  
      if (virt->access_name)
          conf->access_name = virt->access_name;
  
      /* XXX optimize to keep base->sec_ pointers if virt->sec_ array is empty */
      conf->sec_dir = apr_array_append(p, base->sec_dir, virt->sec_dir);
      conf->sec_url = apr_array_append(p, base->sec_url, virt->sec_url);
  
      if (virt->redirect_limit)
          conf->redirect_limit = virt->redirect_limit;
  
      if (virt->subreq_limit)
          conf->subreq_limit = virt->subreq_limit;
  
      if (virt->trace_enable != AP_TRACE_UNSET)
          conf->trace_enable = virt->trace_enable;
  
      if (virt->http09_enable != AP_HTTP09_UNSET)
          conf->http09_enable = virt->http09_enable;
  
      if (virt->http_conformance != AP_HTTP_CONFORMANCE_UNSET)
          conf->http_conformance = virt->http_conformance;
  
      if (virt->http_methods != AP_HTTP_METHODS_UNSET)
          conf->http_methods = virt->http_methods;
  
      if (virt->http_cl_head_zero != AP_HTTP_CL_HEAD_ZERO_UNSET)
          conf->http_cl_head_zero = virt->http_cl_head_zero;
  
      if (virt->http_expect_strict != AP_HTTP_EXPECT_STRICT_UNSET)
          conf->http_expect_strict = virt->http_expect_strict;
  
      /* no action for virt->accf_map, not allowed per-vhost */
  
      if (virt->protocol)
          conf->protocol = virt->protocol;
  
      if (virt->gprof_dir)
          conf->gprof_dir = virt->gprof_dir;
  
      if (virt->error_log_format)
          conf->error_log_format = virt->error_log_format;
  
      if (virt->error_log_conn)
          conf->error_log_conn = virt->error_log_conn;
  
      if (virt->error_log_req)
          conf->error_log_req = virt->error_log_req;
  
      if (virt->conn_log_level) {
          if (!conf->conn_log_level) {
              conf->conn_log_level = virt->conn_log_level;
          }
          else {
              /* apr_array_append actually creates a new array */
              conf->conn_log_level = apr_array_append(p, conf->conn_log_level,
                                                      virt->conn_log_level);
          }
      }
  
      conf->merge_trailers = (virt->merge_trailers != AP_MERGE_TRAILERS_UNSET)
                             ? virt->merge_trailers
                             : base->merge_trailers;
  
      conf->protocols = ((virt->protocols->nelts > 0) ?
                         virt->protocols : base->protocols);
      conf->protocols_honor_order = ((virt->protocols_honor_order < 0) ?
                                         base->protocols_honor_order :
                                         virt->protocols_honor_order);
  
      conf->async_filter = ((virt->async_filter_set) ?
                                         virt->async_filter :
                                         base->async_filter);
      conf->async_filter_set = base->async_filter_set || virt->async_filter_set;
  
      conf->flush_max_threshold = (virt->flush_max_threshold)
                                    ? virt->flush_max_threshold
                                    : base->flush_max_threshold;
      conf->flush_max_pipelined = (virt->flush_max_pipelined >= 0)
                                    ? virt->flush_max_pipelined
                                    : base->flush_max_pipelined;
  
      conf->strict_host_check = (virt->strict_host_check != AP_CORE_CONFIG_UNSET)
                                ? virt->strict_host_check 
                                : base->strict_host_check;
  
      AP_CORE_MERGE_FLAG(strict_host_check, conf, base, virt);
      AP_CORE_MERGE_FLAG(merge_slashes, conf, base, virt);
  
      return conf;
  }
  
  /* Add per-directory configuration entry (for <directory> section);
   * these are part of the core server config.
   */
  
  AP_CORE_DECLARE(void) ap_add_per_dir_conf(server_rec *s, void *dir_config)
  {
      core_server_config *sconf = ap_get_core_module_config(s->module_config);
      void **new_space = (void **)apr_array_push(sconf->sec_dir);
  
      *new_space = dir_config;
  }
  
  AP_CORE_DECLARE(void) ap_add_per_url_conf(server_rec *s, void *url_config)
  {
      core_server_config *sconf = ap_get_core_module_config(s->module_config);
      void **new_space = (void **)apr_array_push(sconf->sec_url);
  
      *new_space = url_config;
  }
  
  AP_CORE_DECLARE(void) ap_add_file_conf(apr_pool_t *p, core_dir_config *conf,
                                         void *url_config)
  {
      void **new_space;
  
      if (!conf->sec_file)
          conf->sec_file = apr_array_make(p, 2, sizeof(ap_conf_vector_t *));
  
      new_space = (void **)apr_array_push(conf->sec_file);
      *new_space = url_config;
  }
  
  AP_CORE_DECLARE(const char *) ap_add_if_conf(apr_pool_t *p,
                                               core_dir_config *conf,
                                               void *if_config)
  {
      void **new_space;
      core_dir_config *new = ap_get_module_config(if_config, &core_module);
  
      if (!conf->sec_if) {
          conf->sec_if = apr_array_make(p, 2, sizeof(ap_conf_vector_t *));
      }
      if (new->condition_ifelse & AP_CONDITION_ELSE) {
          int have_if = 0;
          if (conf->sec_if->nelts > 0) {
              core_dir_config *last;
              ap_conf_vector_t *lastelt = APR_ARRAY_IDX(conf->sec_if,
                                                        conf->sec_if->nelts - 1,
                                                        ap_conf_vector_t *);
              last = ap_get_module_config(lastelt, &core_module);
              if (last->condition_ifelse & AP_CONDITION_IF)
                  have_if = 1;
          }
          if (!have_if)
              return "<Else> or <ElseIf> section without previous <If> or "
                     "<ElseIf> section in same scope";
      }
  
      new_space = (void **)apr_array_push(conf->sec_if);
      *new_space = if_config;
      return NULL;
  }
  
  
  /* We need to do a stable sort, qsort isn't stable.  So to make it stable
   * we'll be maintaining the original index into the list, and using it
   * as the minor key during sorting.  The major key is the number of
   * components (where the root component is zero).
   */
  struct reorder_sort_rec {
      ap_conf_vector_t *elt;
      int orig_index;
  };
  
  static int reorder_sorter(const void *va, const void *vb)
  {
      const struct reorder_sort_rec *a = va;
      const struct reorder_sort_rec *b = vb;
      core_dir_config *core_a;
      core_dir_config *core_b;
  
      core_a = ap_get_core_module_config(a->elt);
      core_b = ap_get_core_module_config(b->elt);
  
      /* a regex always sorts after a non-regex
       */
      if (!core_a->r && core_b->r) {
          return -1;
      }
      else if (core_a->r && !core_b->r) {
          return 1;
      }
  
      /* we always sort next by the number of components
       */
      if (core_a->d_components < core_b->d_components) {
          return -1;
      }
      else if (core_a->d_components > core_b->d_components) {
          return 1;
      }
  
      /* They have the same number of components, we now have to compare
       * the minor key to maintain the original order (from the config.)
       */
      return a->orig_index - b->orig_index;
  }
  
  void ap_core_reorder_directories(apr_pool_t *p, server_rec *s)
  {
      core_server_config *sconf;
      apr_array_header_t *sec_dir;
      struct reorder_sort_rec *sortbin;
      int nelts;
      ap_conf_vector_t **elts;
      int i;
      apr_pool_t *tmp;
  
      sconf = ap_get_core_module_config(s->module_config);
      sec_dir = sconf->sec_dir;
      nelts = sec_dir->nelts;
      elts = (ap_conf_vector_t **)sec_dir->elts;
  
      if (!nelts) {
          /* simple case of already being sorted... */
          /* We're not checking this condition to be fast... we're checking
           * it to avoid trying to palloc zero bytes, which can trigger some
           * memory debuggers to barf
           */
          return;
      }
  
      /* we have to allocate tmp space to do a stable sort */
      apr_pool_create(&tmp, p);
      apr_pool_tag(tmp, "core_reorder_directories");
      sortbin = apr_palloc(tmp, sec_dir->nelts * sizeof(*sortbin));
      for (i = 0; i < nelts; ++i) {
          sortbin[i].orig_index = i;
          sortbin[i].elt = elts[i];
      }
  
      qsort(sortbin, nelts, sizeof(*sortbin), reorder_sorter);
  
      /* and now copy back to the original array */
      for (i = 0; i < nelts; ++i) {
          elts[i] = sortbin[i].elt;
      }
  
      apr_pool_destroy(tmp);
  }
  
  /*****************************************************************
   *
   * There are some elements of the core config structures in which
   * other modules have a legitimate interest (this is ugly, but necessary
   * to preserve NCSA back-compatibility).  So, we have a bunch of accessors
   * here...
   */
  
  AP_DECLARE(int) ap_allow_options(request_rec *r)
  {
      core_dir_config *conf =
        (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      return conf->opts;
  }
  
  AP_DECLARE(int) ap_allow_overrides(request_rec *r)
  {
      core_dir_config *conf;
      conf = (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      return conf->override;
  }
  
  /*
   * Optional function coming from mod_authn_core, used for
   * retrieving the type of authorization
   */
  static APR_OPTIONAL_FN_TYPE(authn_ap_auth_type) *authn_ap_auth_type;
  
  AP_DECLARE(const char *) ap_auth_type(request_rec *r)
  {
      if (authn_ap_auth_type) {
          return authn_ap_auth_type(r);
      }
      return NULL;
  }
  
  /*
   * Optional function coming from mod_authn_core, used for
   * retrieving the authorization realm
   */
  static APR_OPTIONAL_FN_TYPE(authn_ap_auth_name) *authn_ap_auth_name;
  
  AP_DECLARE(const char *) ap_auth_name(request_rec *r)
  {
      if (authn_ap_auth_name) {
          return authn_ap_auth_name(r);
      }
      return NULL;
  }
  
  /*
   * Optional function coming from mod_access_compat, used to determine how
     access control interacts with authentication/authorization
   */
  static APR_OPTIONAL_FN_TYPE(access_compat_ap_satisfies) *access_compat_ap_satisfies;
  
  AP_DECLARE(int) ap_satisfies(request_rec *r)
  {
      if (access_compat_ap_satisfies) {
          return access_compat_ap_satisfies(r);
      }
      return SATISFY_NOSPEC;
  }
  
  AP_DECLARE(const char *) ap_document_root(request_rec *r) /* Don't use this! */
  {
      core_server_config *sconf;
      core_request_config *rconf = ap_get_core_module_config(r->request_config);
      if (rconf->document_root)
          return rconf->document_root;
      sconf = ap_get_core_module_config(r->server->module_config);
      return sconf->ap_document_root;
  }
  
  AP_DECLARE(const char *) ap_context_prefix(request_rec *r)
  {
      core_request_config *conf = ap_get_core_module_config(r->request_config);
      if (conf->context_prefix)
          return conf->context_prefix;
      else
          return "";
  }
  
  AP_DECLARE(const char *) ap_context_document_root(request_rec *r)
  {
      core_request_config *conf = ap_get_core_module_config(r->request_config);
      if (conf->context_document_root)
          return conf->context_document_root;
      else
          return ap_document_root(r);
  }
  
  AP_DECLARE(void) ap_set_document_root(request_rec *r, const char *document_root)
  {
      core_request_config *conf = ap_get_core_module_config(r->request_config);
      conf->document_root = document_root;
  }
  
  AP_DECLARE(void) ap_set_context_info(request_rec *r, const char *context_prefix,
                                       const char *context_document_root)
  {
      core_request_config *conf = ap_get_core_module_config(r->request_config);
      if (context_prefix)
          conf->context_prefix = context_prefix;
      if (context_document_root)
          conf->context_document_root = context_document_root;
  }
  
  /* Should probably just get rid of this... the only code that cares is
   * part of the core anyway (and in fact, it isn't publicised to other
   * modules).
   */
  
  char *ap_response_code_string(request_rec *r, int error_index)
  {
      core_dir_config *dirconf;
      core_request_config *reqconf = ap_get_core_module_config(r->request_config);
      const char *err;
      const char *response;
      ap_expr_info_t *expr;
  
      /* check for string registered via ap_custom_response() first */
      if (reqconf->response_code_strings != NULL
              && reqconf->response_code_strings[error_index] != NULL) {
          return reqconf->response_code_strings[error_index];
      }
  
      /* check for string specified via ErrorDocument */
      dirconf = ap_get_core_module_config(r->per_dir_config);
  
      if (!dirconf->response_code_exprs) {
          return NULL;
      }
  
      expr = apr_hash_get(dirconf->response_code_exprs, &error_index,
              sizeof(error_index));
      if (!expr) {
          return NULL;
      }
  
      /* special token to indicate revert back to default */
      if ((char *) expr == &errordocument_default) {
          return NULL;
      }
  
      err = NULL;
      response = ap_expr_str_exec(r, expr, &err);
      if (err) {
          ap_log_rerror(
                  APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(02841) "core: ErrorDocument: can't "
                  "evaluate require expression: %s", err);
          return NULL;
      }
  
      /* alas, duplication required as we return not-const */
      return apr_pstrdup(r->pool, response);
  }
  
  
  /* Code from Harald Hanche-Olsen <hanche@imf.unit.no> */
  static APR_INLINE int do_double_reverse (int double_reverse,
                                           const char *remote_host,
                                           apr_sockaddr_t *client_addr,
                                           apr_pool_t *pool)
  {
      apr_sockaddr_t *sa;
      apr_status_t rv;
  
      if (double_reverse) {
          /* already done */
          return double_reverse;
      }
  
      if (remote_host == NULL || remote_host[0] == '\0') {
          /* single reverse failed, so don't bother */
          return -1;
      }
  
      rv = apr_sockaddr_info_get(&sa, remote_host, APR_UNSPEC, 0, 0, pool);
      if (rv == APR_SUCCESS) {
          while (sa) {
              if (apr_sockaddr_equal(sa, client_addr)) {
                  return 1;
              }
  
              sa = sa->next;
          }
      }
  
      return -1;
  }
  
  AP_DECLARE(const char *) ap_get_remote_host(conn_rec *conn, void *dir_config,
                                              int type, int *str_is_ip)
  {
      int hostname_lookups;
      int ignored_str_is_ip;
  
      if (!str_is_ip) { /* caller doesn't want to know */
          str_is_ip = &ignored_str_is_ip;
      }
      *str_is_ip = 0;
  
      /* If we haven't checked the host name, and we want to */
      if (dir_config) {
          hostname_lookups = ((core_dir_config *)ap_get_core_module_config(dir_config))
                             ->hostname_lookups;
  
          if (hostname_lookups == HOSTNAME_LOOKUP_UNSET) {
              hostname_lookups = HOSTNAME_LOOKUP_OFF;
          }
      }
      else {
          /* the default */
          hostname_lookups = HOSTNAME_LOOKUP_OFF;
      }
  
      if (type != REMOTE_NOLOOKUP
          && conn->remote_host == NULL
          && (type == REMOTE_DOUBLE_REV
          || hostname_lookups != HOSTNAME_LOOKUP_OFF)) {
  
          if (apr_getnameinfo(&conn->remote_host, conn->client_addr, 0)
              == APR_SUCCESS) {
              ap_str_tolower(conn->remote_host);
  
              if (hostname_lookups == HOSTNAME_LOOKUP_DOUBLE) {
                  conn->double_reverse = do_double_reverse(conn->double_reverse,
                                                           conn->remote_host,
                                                           conn->client_addr,
                                                           conn->pool);
                  if (conn->double_reverse != 1) {
                      conn->remote_host = NULL;
                  }
              }
          }
  
          /* if failed, set it to the NULL string to indicate error */
          if (conn->remote_host == NULL) {
              conn->remote_host = "";
          }
      }
  
      if (type == REMOTE_DOUBLE_REV) {
          conn->double_reverse = do_double_reverse(conn->double_reverse,
                                                   conn->remote_host,
                                                   conn->client_addr, conn->pool);
          if (conn->double_reverse == -1) {
              return NULL;
          }
      }
  
      /*
       * Return the desired information; either the remote DNS name, if found,
       * or either NULL (if the hostname was requested) or the IP address
       * (if any identifier was requested).
       */
      if (conn->remote_host != NULL && conn->remote_host[0] != '\0') {
          return conn->remote_host;
      }
      else {
          if (type == REMOTE_HOST || type == REMOTE_DOUBLE_REV) {
              return NULL;
          }
          else {
              *str_is_ip = 1;
              return conn->client_ip;
          }
      }
  }
  
  AP_DECLARE(const char *) ap_get_useragent_host(request_rec *r,
                                                 int type, int *str_is_ip)
  {
      conn_rec *conn = r->connection;
      int hostname_lookups;
      int ignored_str_is_ip;
  
      /* Guard here when examining the host before the read_request hook
       * has populated an r->useragent_addr
       */
      if (!r->useragent_addr || (r->useragent_addr == conn->client_addr)) {
          return ap_get_remote_host(conn, r->per_dir_config, type, str_is_ip);
      }
  
      if (!str_is_ip) { /* caller doesn't want to know */
          str_is_ip = &ignored_str_is_ip;
      }
      *str_is_ip = 0;
  
      hostname_lookups = ((core_dir_config *)
                          ap_get_core_module_config(r->per_dir_config))
                              ->hostname_lookups;
      if (hostname_lookups == HOSTNAME_LOOKUP_UNSET) {
          hostname_lookups = HOSTNAME_LOOKUP_OFF;
      }
  
      if (type != REMOTE_NOLOOKUP
          && r->useragent_host == NULL
          && (type == REMOTE_DOUBLE_REV
          || hostname_lookups != HOSTNAME_LOOKUP_OFF)) {
  
          if (apr_getnameinfo(&r->useragent_host, r->useragent_addr, 0)
              == APR_SUCCESS) {
              ap_str_tolower(r->useragent_host);
  
              if (hostname_lookups == HOSTNAME_LOOKUP_DOUBLE) {
                  r->double_reverse = do_double_reverse(r->double_reverse,
                                                        r->useragent_host,
                                                        r->useragent_addr,
                                                        r->pool);
                  if (r->double_reverse != 1) {
                      r->useragent_host = NULL;
                  }
              }
          }
  
          /* if failed, set it to the NULL string to indicate error */
          if (r->useragent_host == NULL) {
              r->useragent_host = "";
          }
      }
  
      if (type == REMOTE_DOUBLE_REV) {
          r->double_reverse = do_double_reverse(r->double_reverse,
                                                r->useragent_host,
                                                r->useragent_addr, r->pool);
          if (r->double_reverse == -1) {
              return NULL;
          }
      }
  
      /*
       * Return the desired information; either the remote DNS name, if found,
       * or either NULL (if the hostname was requested) or the IP address
       * (if any identifier was requested).
       */
      if (r->useragent_host != NULL && r->useragent_host[0] != '\0') {
          return r->useragent_host;
      }
      else {
          if (type == REMOTE_HOST || type == REMOTE_DOUBLE_REV) {
              return NULL;
          }
          else {
              *str_is_ip = 1;
              return r->useragent_ip;
          }
      }
  }
  
  /*
   * Optional function coming from mod_ident, used for looking up ident user
   */
  static APR_OPTIONAL_FN_TYPE(ap_ident_lookup) *ident_lookup;
  
  AP_DECLARE(const char *) ap_get_remote_logname(request_rec *r)
  {
      if (r->connection->remote_logname != NULL) {
          return r->connection->remote_logname;
      }
  
      if (ident_lookup) {
          return ident_lookup(r);
      }
  
      return NULL;
  }
  
  /* There are two options regarding what the "name" of a server is.  The
   * "canonical" name as defined by ServerName and Port, or the "client's
   * name" as supplied by a possible Host: header or full URI.
   *
   * The DNS option to UseCanonicalName causes this routine to do a
   * reverse lookup on the local IP address of the connection and use
   * that for the ServerName. This makes its value more reliable while
   * at the same time allowing Demon's magic virtual hosting to work.
   * The assumption is that DNS lookups are sufficiently quick...
   * -- fanf 1998-10-03
   */
  AP_DECLARE(const char *) ap_get_server_name(request_rec *r)
  {
      conn_rec *conn = r->connection;
      core_dir_config *d;
      const char *retval;
  
      d = (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      switch (d->use_canonical_name) {
          case USE_CANONICAL_NAME_ON:
              retval = r->server->server_hostname;
              break;
          case USE_CANONICAL_NAME_DNS:
              if (conn->local_host == NULL) {
                  if (apr_getnameinfo(&conn->local_host,
                                  conn->local_addr, 0) != APR_SUCCESS)
                      conn->local_host = apr_pstrdup(conn->pool,
                                                 r->server->server_hostname);
                  else {
                      ap_str_tolower(conn->local_host);
                  }
              }
              retval = conn->local_host;
              break;
          case USE_CANONICAL_NAME_OFF:
          case USE_CANONICAL_NAME_UNSET:
              retval = r->hostname ? r->hostname : r->server->server_hostname;
              break;
          default:
              ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00109)
                           "ap_get_server_name: Invalid UCN Option somehow");
              retval = "localhost";
              break;
      }
      return retval;
  }
  
  /*
   * Get the current server name from the request for the purposes
   * of using in a URL.  If the server name is an IPv6 literal
   * address, it will be returned in URL format (e.g., "[fe80::1]").
   */
  AP_DECLARE(const char *) ap_get_server_name_for_url(request_rec *r)
  {
      const char *plain_server_name = ap_get_server_name(r);
  
  #if APR_HAVE_IPV6
      if (ap_strchr_c(plain_server_name, ':')) { /* IPv6 literal? */
          return apr_pstrcat(r->pool, "[", plain_server_name, "]", NULL);
      }
  #endif
      return plain_server_name;
  }
  
  AP_DECLARE(apr_port_t) ap_get_server_port(const request_rec *r)
  {
      apr_port_t port;
      core_dir_config *d =
        (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      switch (d->use_canonical_name) {
          case USE_CANONICAL_NAME_OFF:
          case USE_CANONICAL_NAME_DNS:
          case USE_CANONICAL_NAME_UNSET:
              if (d->use_canonical_phys_port == USE_CANONICAL_PHYS_PORT_ON)
                  port = r->parsed_uri.port_str ? r->parsed_uri.port :
                         r->connection->local_addr->port ? r->connection->local_addr->port :
                         r->server->port ? r->server->port :
                         ap_default_port(r);
              else /* USE_CANONICAL_PHYS_PORT_OFF or USE_CANONICAL_PHYS_PORT_UNSET */
                  port = r->parsed_uri.port_str ? r->parsed_uri.port :
                         r->server->port ? r->server->port :
                         ap_default_port(r);
              break;
          case USE_CANONICAL_NAME_ON:
              /* With UseCanonicalName on (and in all versions prior to 1.3)
               * Apache will use the hostname and port specified in the
               * ServerName directive to construct a canonical name for the
               * server. (If no port was specified in the ServerName
               * directive, Apache uses the port supplied by the client if
               * any is supplied, and finally the default port for the protocol
               * used.
               */
              if (d->use_canonical_phys_port == USE_CANONICAL_PHYS_PORT_ON)
                  port = r->server->port ? r->server->port :
                         r->connection->local_addr->port ? r->connection->local_addr->port :
                         ap_default_port(r);
              else /* USE_CANONICAL_PHYS_PORT_OFF or USE_CANONICAL_PHYS_PORT_UNSET */
                  port = r->server->port ? r->server->port :
                         ap_default_port(r);
              break;
          default:
              ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00110)
                           "ap_get_server_port: Invalid UCN Option somehow");
              port = ap_default_port(r);
              break;
      }
  
      return port;
  }
  
  AP_DECLARE(char *) ap_construct_url(apr_pool_t *p, const char *uri,
                                      request_rec *r)
  {
      unsigned port = ap_get_server_port(r);
      const char *host = ap_get_server_name_for_url(r);
  
      if (ap_is_default_port(port, r)) {
          return apr_pstrcat(p, ap_http_scheme(r), "://", host, uri, NULL);
      }
  
      return apr_psprintf(p, "%s://%s:%u%s", ap_http_scheme(r), host, port, uri);
  }
  
  AP_DECLARE(apr_off_t) ap_get_limit_req_body(const request_rec *r)
  {
      core_dir_config *d =
        (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      if (d->limit_req_body == AP_LIMIT_REQ_BODY_UNSET) {
          return AP_DEFAULT_LIMIT_REQ_BODY;
      }
  
      return d->limit_req_body;
  }
  
  AP_DECLARE(apr_size_t) ap_get_read_buf_size(const request_rec *r)
  {
      core_dir_config *d = ap_get_core_module_config(r->per_dir_config);
  
      return d->read_buf_size ? d->read_buf_size : AP_IOBUFSIZE;
  }
  
  
  /*****************************************************************
   *
   * Commands... this module handles almost all of the NCSA httpd.conf
   * commands, but most of the old srm.conf is in the modules.
   */
  
  
  /* returns a parent if it matches the given directive */
  static const ap_directive_t * find_parent(const ap_directive_t *dirp,
                                            const char *what)
  {
      while (dirp->parent != NULL) {
          dirp = dirp->parent;
  
          /* ### it would be nice to have atom-ized directives */
          if (ap_cstr_casecmp(dirp->directive, what) == 0)
              return dirp;
      }
  
      return NULL;
  }
  
  AP_DECLARE(const char *) ap_check_cmd_context(cmd_parms *cmd,
                                                unsigned forbidden)
  {
      const char *gt = (cmd->cmd->name[0] == '<'
                        && cmd->cmd->name[strlen(cmd->cmd->name)-1] != '>')
                           ? ">" : "";
      const ap_directive_t *found;
  
      if ((forbidden & NOT_IN_VIRTUALHOST) && cmd->server->is_virtual) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name, gt,
                             " cannot occur within <VirtualHost> section", NULL);
      }
  
      if ((forbidden & NOT_IN_DIR_CONTEXT) && cmd->limited != -1) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name, gt,
                             " cannot occur within <Limit> or <LimitExcept> "
                             "section", NULL);
      }
  
      if ((forbidden & NOT_IN_HTACCESS) && (cmd->pool == cmd->temp_pool)) {
           return apr_pstrcat(cmd->pool, cmd->cmd->name, gt,
                              " cannot occur within htaccess files", NULL);
      }
  
      if ((forbidden & NOT_IN_DIR_CONTEXT) == NOT_IN_DIR_CONTEXT) {
          if (cmd->path != NULL) {
              return apr_pstrcat(cmd->pool, cmd->cmd->name, gt,
                              " cannot occur within directory context", NULL);
          }
          if (cmd->cmd->req_override & EXEC_ON_READ) {
              /* EXEC_ON_READ must be NOT_IN_DIR_CONTEXT, if not, it will
               * (deliberately) segfault below in the individual tests...
               */
              return NULL;
          }
      }
  
      if (((forbidden & NOT_IN_DIRECTORY)
           && ((found = find_parent(cmd->directive, "<Directory"))
               || (found = find_parent(cmd->directive, "<DirectoryMatch"))))
          || ((forbidden & NOT_IN_LOCATION)
              && ((found = find_parent(cmd->directive, "<Location"))
                  || (found = find_parent(cmd->directive, "<LocationMatch"))))
          || ((forbidden & NOT_IN_FILES)
              && ((found = find_parent(cmd->directive, "<Files"))
                  || (found = find_parent(cmd->directive, "<FilesMatch"))
                  || (found = find_parent(cmd->directive, "<If"))
                  || (found = find_parent(cmd->directive, "<ElseIf"))
                  || (found = find_parent(cmd->directive, "<Else"))))
          || ((forbidden & NOT_IN_PROXY)
              && ((found = find_parent(cmd->directive, "<Proxy"))
                  || (found = find_parent(cmd->directive, "<ProxyMatch"))))) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name, gt,
                             " cannot occur within ", found->directive,
                             "> section", NULL);
      }
  
      return NULL;
  }
  
  static const char *set_access_name(cmd_parms *cmd, void *dummy,
                                     const char *arg)
  {
      void *sconf = cmd->server->module_config;
      core_server_config *conf = ap_get_core_module_config(sconf);
  
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      conf->access_name = apr_pstrdup(cmd->pool, arg);
      return NULL;
  }
  
  AP_DECLARE(const char *) ap_resolve_env(apr_pool_t *p, const char * word)
  {
  # define SMALL_EXPANSION 5
      struct sll {
          struct sll *next;
          const char *string;
          apr_size_t len;
      } *result, *current, sresult[SMALL_EXPANSION];
      char *res_buf, *cp;
      const char *s, *e, *ep;
      unsigned spc;
      apr_size_t outlen;
  
      s = ap_strchr_c(word, '$');
      if (!s) {
          return word;
      }
  
      /* well, actually something to do */
      ep = word + strlen(word);
      spc = 0;
      result = current = &(sresult[spc++]);
      current->next = NULL;
      current->string = word;
      current->len = s - word;
      outlen = current->len;
  
      do {
          /* prepare next entry */
          if (current->len) {
              current->next = (spc < SMALL_EXPANSION)
                              ? &(sresult[spc++])
                              : (struct sll *)apr_palloc(p,
                                                         sizeof(*current->next));
              current = current->next;
              current->next = NULL;
              current->len = 0;
          }
  
          if (*s == '$') {
              if (s[1] == '{' && (e = ap_strchr_c(s+2, '}'))) {
                  char *name = apr_pstrmemdup(p, s+2, e-s-2);
                  char *dflt = ap_strstr(name, "?=");
                  if (dflt) {
                      /* Default value for when var is not defined */
                      *dflt = '\0';
                      dflt += 2;
                  }
                  word = NULL;
                  if (server_config_defined_vars)
                      word = apr_table_get(server_config_defined_vars, name);
                  if (!word)
                      word = apr_pstrdup(p, getenv(name));
                  if (word) {
                      current->string = word;
                      current->len = strlen(word);
                      outlen += current->len;
                  }
                  else if (dflt) {
                      current->string = dflt;
                      current->len = strlen(dflt);
                      outlen += current->len;
                  }
                  else {
                      if (ap_strchr(name, ':') == 0)
                          ap_log_error(APLOG_MARK, APLOG_WARNING, 0, NULL, APLOGNO(00111)
                                       "Config variable ${%s} is not defined",
                                       name);
                      current->string = s;
                      current->len = e - s + 1;
                      outlen += current->len;
                  }
                  s = e + 1;
              }
              else {
                  current->string = s++;
                  current->len = 1;
                  ++outlen;
              }
          }
          else {
              word = s;
              s = ap_strchr_c(s, '$');
              current->string = word;
              current->len = s ? s - word : ep - word;
              outlen += current->len;
          }
      } while (s && *s);
  
      /* assemble result */
      res_buf = cp = apr_palloc(p, outlen + 1);
      do {
          if (result->len) {
              memcpy(cp, result->string, result->len);
              cp += result->len;
          }
          result = result->next;
      } while (result);
      res_buf[outlen] = '\0';
  
      return res_buf;
  }
  
  /* pconf cleanup - clear global variables set from config here. */
  static apr_status_t reset_config(void *dummy)
  {
      ap_server_config_defines = saved_server_config_defines;
      saved_server_config_defines = NULL;
      server_config_defined_vars = NULL;
      core_state_dir = NULL;
      ap_runtime_dir = NULL;
  
      return APR_SUCCESS;
  }
  
  /*
   * Make sure we can revert the effects of Define/UnDefine when restarting.
   * This function must be called once per loading of the config, before
   * ap_server_config_defines is changed. This may be during reading of the
   * config, which is even before the pre_config hook is run (due to
   * EXEC_ON_READ for Define/UnDefine).
   */
  static void init_config_defines(apr_pool_t *pconf)
  {
      saved_server_config_defines = ap_server_config_defines;
      /* Use apr_array_copy instead of apr_array_copy_hdr because it does not
       * protect from the way unset_define removes entries.
       */
      ap_server_config_defines = apr_array_copy(pconf, ap_server_config_defines);
  }
  
  static const char *set_define(cmd_parms *cmd, void *dummy,
                                const char *name, const char *value)
  {
      if (cmd->parent && ap_cstr_casecmp(cmd->parent->directive, "<VirtualHost")) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name, " is not valid in ",
                                        cmd->parent->directive, " context", NULL);
      }
  
      if (ap_strchr_c(name, ':') != NULL) {
          return "Variable name must not contain ':'";
      }
  
      if (!saved_server_config_defines) {
          init_config_defines(cmd->pool);
      }
      if (!ap_exists_config_define(name)) {
          *(const char **)apr_array_push(ap_server_config_defines) = name;
      }
      if (value) {
          if (!server_config_defined_vars) {
              server_config_defined_vars = apr_table_make(cmd->pool, 5);
          }
          apr_table_setn(server_config_defined_vars, name, value);
      }
  
      return NULL;
  }
  
  static const char *unset_define(cmd_parms *cmd, void *dummy,
                                  const char *name)
  {
      int i;
      const char **defines;
      if (cmd->parent && ap_cstr_casecmp(cmd->parent->directive, "<VirtualHost")) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name, " is not valid in ",
                                        cmd->parent->directive, " context", NULL);
      }
  
      if (ap_strchr_c(name, ':') != NULL) {
          return "Variable name must not contain ':'";
      }
  
      if (!saved_server_config_defines) {
          init_config_defines(cmd->pool);
      }
  
      defines = (const char **)ap_server_config_defines->elts;
      for (i = 0; i < ap_server_config_defines->nelts; i++) {
          if (strcmp(defines[i], name) == 0) {
              defines[i] = *(const char **)apr_array_pop(ap_server_config_defines);
              break;
          }
      }
  
      if (server_config_defined_vars) {
          apr_table_unset(server_config_defined_vars, name);
      }
  
      return NULL;
  }
  
  static const char *generate_message(cmd_parms *cmd, void *dummy,
                                      const char *arg)
  {
      /* cast with 64-bit warning avoidance */
      int level = (cmd->info==(void*)APLOG_ERR)? APLOG_ERR: APLOG_WARNING;
      char * msg;
  
      /* get position information from wherever we can? */
      ap_configfile_t * cf = cmd->config_file;
      ap_directive_t const * ed1 = cmd->directive;
      ap_directive_t const * ed2 = cmd->err_directive;
  
      /* expect an argument */
      if (!arg || !*arg) {
          return "The Error or Warning directive was used with no message.";
      }
  
      /* set message, strip off quotes if necessary */
      msg = (char *)arg;
      if (*arg == '"' || *arg == '\'') {
          apr_size_t len = strlen(arg);
          char last = *(arg + len - 1);
  
          if (*arg == last) {
              msg = apr_pstrndup(cmd->pool, arg + 1, len - 2);
          }
      }
  
      /* generate error or warning with a configuration file position.
       * the log is displayed on the terminal as no log file is opened yet.
       */
      ap_log_error(APLOG_MARK, level, 0, NULL,
                   "%s on line %d of %s", msg,
                   cf? cf->line_number:
                     ed1? ed1->line_num:
                       ed2? ed2->line_num: -1,
                   cf? cf->name:
                     ed1? ed1->filename:
                       ed2? ed2->filename: "<UNKNOWN>");
  
      /* message displayed above, return will stop configuration processing */
      return level==APLOG_ERR?
          "Configuration processing stopped by Error directive": NULL;
  }
  
  #ifdef GPROF
  static const char *set_gprof_dir(cmd_parms *cmd, void *dummy, const char *arg)
  {
      void *sconf = cmd->server->module_config;
      core_server_config *conf = ap_get_core_module_config(sconf);
  
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      conf->gprof_dir = apr_pstrdup(cmd->pool, arg);
      return NULL;
  }
  #endif /*GPROF*/
  
  static const char *set_add_default_charset(cmd_parms *cmd,
                                             void *d_, const char *arg)
  {
      core_dir_config *d = d_;
  
      if (!ap_cstr_casecmp(arg, "Off")) {
         d->add_default_charset = ADD_DEFAULT_CHARSET_OFF;
      }
      else if (!ap_cstr_casecmp(arg, "On")) {
         d->add_default_charset = ADD_DEFAULT_CHARSET_ON;
         d->add_default_charset_name = DEFAULT_ADD_DEFAULT_CHARSET_NAME;
      }
      else {
         d->add_default_charset = ADD_DEFAULT_CHARSET_ON;
         d->add_default_charset_name = arg;
      }
  
      return NULL;
  }
  
  static const char *set_document_root(cmd_parms *cmd, void *dummy,
                                       const char *arg)
  {
      void *sconf = cmd->server->module_config;
      core_server_config *conf = ap_get_core_module_config(sconf);
  
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      /* When ap_document_root_check is false; skip all the stuff below */
      if (!ap_document_root_check) {
         conf->ap_document_root = arg;
         return NULL;
      }
  
      /* Make it absolute, relative to ServerRoot */
      arg = ap_server_root_relative(cmd->pool, arg);
      if (arg == NULL) {
          return "DocumentRoot must be a directory";
      }
  
      if (apr_filepath_merge((char**)&conf->ap_document_root, NULL, arg,
                             APR_FILEPATH_TRUENAME, cmd->pool) != APR_SUCCESS
          || !ap_is_directory(cmd->temp_pool, arg)) {
          if (cmd->server->is_virtual) {
              ap_log_perror(APLOG_MARK, APLOG_STARTUP, 0,
                            cmd->pool, APLOGNO(00112)
                            "Warning: DocumentRoot [%s] does not exist",
                            arg);
              conf->ap_document_root = arg;
          }
          else {
              return apr_psprintf(cmd->pool, 
                                  "DocumentRoot '%s' is not a directory, or is not readable",
                                  arg);
          }
      }
      return NULL;
  }
  
  AP_DECLARE(void) ap_custom_response(request_rec *r, int status,
                                      const char *string)
  {
      core_request_config *conf = ap_get_core_module_config(r->request_config);
      int idx;
  
      if (conf->response_code_strings == NULL) {
          conf->response_code_strings =
              apr_pcalloc(r->pool,
                          sizeof(*conf->response_code_strings) * RESPONSE_CODES);
      }
  
      idx = ap_index_of_response(status);
  
      conf->response_code_strings[idx] =
         ((ap_is_url(string) || (*string == '/')) && (*string != '"')) ?
         apr_pstrdup(r->pool, string) : apr_pstrcat(r->pool, "\"", string, NULL);
  }
  
  static const char *set_error_document(cmd_parms *cmd, void *conf_,
                                        const char *errno_str, const char *msg)
  {
      core_dir_config *conf = conf_;
      int error_number, index_number, idx500;
      enum { MSG, LOCAL_PATH, REMOTE_PATH } what = MSG;
  
      /* 1st parameter should be a 3 digit number, which we recognize;
       * convert it into an array index
       */
      error_number = atoi(errno_str);
      idx500 = ap_index_of_response(HTTP_INTERNAL_SERVER_ERROR);
  
      if (error_number == HTTP_INTERNAL_SERVER_ERROR) {
          index_number = idx500;
      }
      else if ((index_number = ap_index_of_response(error_number)) == idx500) {
          return apr_pstrcat(cmd->pool, "Unsupported HTTP response code ",
                             errno_str, NULL);
      }
  
      /* Heuristic to determine second argument. */
      if (ap_strchr_c(msg,' '))
          what = MSG;
      else if (msg[0] == '/')
          what = LOCAL_PATH;
      else if (ap_is_url(msg))
          what = REMOTE_PATH;
      else
          what = MSG;
  
      /* The entry should be ignored if it is a full URL for a 401 error */
  
      if (error_number == 401 && what == REMOTE_PATH) {
          ap_log_error(APLOG_MARK, APLOG_NOTICE, 0, cmd->server, APLOGNO(00113)
                       "%s:%d cannot use a full URL in a 401 ErrorDocument "
                       "directive --- ignoring!", cmd->directive->filename, cmd->directive->line_num);
      }
      else { /* Store it... */
          if (conf->response_code_exprs == NULL) {
              conf->response_code_exprs = apr_hash_make(cmd->pool);
          }
  
          if (ap_cstr_casecmp(msg, "default") == 0) {
              /* special case: ErrorDocument 404 default restores the
               * canned server error response
               */
              apr_hash_set(conf->response_code_exprs,
                      apr_pmemdup(cmd->pool, &index_number, sizeof(index_number)),
                      sizeof(index_number), &errordocument_default);
          }
          else {
              ap_expr_info_t *expr;
              const char *expr_err = NULL;
  
              /* hack. Prefix a " if it is a msg; as that is what
               * http_protocol.c relies on to distinguish between
               * a msg and a (local) path.
               */
              const char *response =
                      (what == MSG) ? apr_pstrcat(cmd->pool, "\"", msg, NULL) :
                              apr_pstrdup(cmd->pool, msg);
  
              expr = ap_expr_parse_cmd(cmd, response, AP_EXPR_FLAG_STRING_RESULT,
                      &expr_err, NULL);
  
              if (expr_err) {
                  return apr_pstrcat(cmd->temp_pool,
                                     "Cannot parse expression in ErrorDocument: ",
                                     expr_err, NULL);
              }
  
              apr_hash_set(conf->response_code_exprs,
                      apr_pmemdup(cmd->pool, &index_number, sizeof(index_number)),
                      sizeof(index_number), expr);
  
          }
      }
  
      return NULL;
  }
  
  static const char *set_allow_opts(cmd_parms *cmd, allow_options_t *opts,
                                    const char *l)
  {
      allow_options_t opt;
      int first = 1;
  
      char *w, *p = (char *) l;
      char *tok_state;
  
      while ((w = apr_strtok(p, ",", &tok_state)) != NULL) {
  
          if (first) {
              p = NULL;
              *opts = OPT_NONE;
              first = 0;
          }
  
          if (!ap_cstr_casecmp(w, "Indexes")) {
              opt = OPT_INDEXES;
          }
          else if (!ap_cstr_casecmp(w, "Includes")) {
              /* If Includes is permitted, both Includes and
               * IncludesNOEXEC may be changed. */
              opt = (OPT_INCLUDES | OPT_INC_WITH_EXEC);
          }
          else if (!ap_cstr_casecmp(w, "IncludesNOEXEC")) {
              opt = OPT_INCLUDES;
          }
          else if (!ap_cstr_casecmp(w, "FollowSymLinks")) {
              opt = OPT_SYM_LINKS;
          }
          else if (!ap_cstr_casecmp(w, "SymLinksIfOwnerMatch")) {
              opt = OPT_SYM_OWNER;
          }
          else if (!ap_cstr_casecmp(w, "ExecCGI")) {
              opt = OPT_EXECCGI;
          }
          else if (!ap_cstr_casecmp(w, "MultiViews")) {
              opt = OPT_MULTI;
          }
          else if (!ap_cstr_casecmp(w, "RunScripts")) { /* AI backcompat. Yuck */
              opt = OPT_MULTI|OPT_EXECCGI;
          }
          else if (!ap_cstr_casecmp(w, "None")) {
              opt = OPT_NONE;
          }
          else if (!ap_cstr_casecmp(w, "All")) {
              opt = OPT_ALL;
          }
          else {
              return apr_pstrcat(cmd->pool, "Illegal option ", w, NULL);
          }
  
          *opts |= opt;
      }
  
      (*opts) &= (~OPT_UNSET);
  
      return NULL;
  }
  
  static const char *set_override(cmd_parms *cmd, void *d_, const char *l)
  {
      core_dir_config *d = d_;
      char *w;
      char *k, *v;
      const char *err;
  
      /* Throw a warning if we're in <Location> or <Files> */
      if (ap_check_cmd_context(cmd, NOT_IN_LOCATION | NOT_IN_FILES)) {
          ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00114)
                       "Useless use of AllowOverride in line %d of %s.",
                       cmd->directive->line_num, cmd->directive->filename);
      }
      if ((err = ap_check_cmd_context(cmd, NOT_IN_HTACCESS)) != NULL)
          return err;
  
      d->override = OR_NONE;
      while (l[0]) {
          w = ap_getword_conf(cmd->temp_pool, &l);
  
          k = w;
          v = strchr(k, '=');
          if (v) {
                  *v++ = '\0';
          }
  
          if (!ap_cstr_casecmp(w, "Limit")) {
              d->override |= OR_LIMIT;
          }
          else if (!ap_cstr_casecmp(k, "Options")) {
              d->override |= OR_OPTIONS;
              if (v)
                  set_allow_opts(cmd, &(d->override_opts), v);
              else
                  d->override_opts = OPT_ALL;
          }
          else if (!ap_cstr_casecmp(w, "FileInfo")) {
              d->override |= OR_FILEINFO;
          }
          else if (!ap_cstr_casecmp(w, "AuthConfig")) {
              d->override |= OR_AUTHCFG;
          }
          else if (!ap_cstr_casecmp(w, "Indexes")) {
              d->override |= OR_INDEXES;
          }
          else if (!ap_cstr_casecmp(w, "Nonfatal")) {
              if (!v) {
                  return apr_pstrcat(cmd->pool, "=Override, =Unknown or =All expected after ", w, NULL);
              }
              else if (!ap_cstr_casecmp(v, "Override")) {
                  d->override |= NONFATAL_OVERRIDE;
              }
              else if (!ap_cstr_casecmp(v, "Unknown")) {
                  d->override |= NONFATAL_UNKNOWN;
              }
              else if (!ap_cstr_casecmp(v, "All")) {
                  d->override |= NONFATAL_ALL;
              }
          }
          else if (!ap_cstr_casecmp(w, "None")) {
              d->override = OR_NONE;
          }
          else if (!ap_cstr_casecmp(w, "All")) {
              d->override = OR_ALL;
          }
          else {
              return apr_pstrcat(cmd->pool, "Illegal override option ", w, NULL);
          }
  
          d->override &= ~OR_UNSET;
      }
  
      return NULL;
  }
  
  static const char *set_cgi_pass_auth(cmd_parms *cmd, void *d_, int flag)
  {
      core_dir_config *d = d_;
  
      d->cgi_pass_auth = flag ? AP_CGI_PASS_AUTH_ON : AP_CGI_PASS_AUTH_OFF;
  
      return NULL;
  }
  
  static const char *set_cgi_var(cmd_parms *cmd, void *d_,
                                 const char *var, const char *rule_)
  {
      core_dir_config *d = d_;
      char *rule = apr_pstrdup(cmd->pool, rule_);
  
      ap_str_tolower(rule);
  
      if (!strcmp(var, "REQUEST_URI")) {
          if (strcmp(rule, "current-uri") && strcmp(rule, "original-uri")) {
              return "Valid rules for REQUEST_URI are 'current-uri' and 'original-uri'";
          }
      }
      else {
          return apr_pstrcat(cmd->pool, "Unrecognized CGI variable: \"",
                             var, "\"", NULL);
      }
  
      if (!d->cgi_var_rules) {
          d->cgi_var_rules = apr_hash_make(cmd->pool);
      }
      apr_hash_set(d->cgi_var_rules, var, APR_HASH_KEY_STRING, rule);
      return NULL;
  }
  
  static const char *set_qualify_redirect_url(cmd_parms *cmd, void *d_, int flag)
  {
      core_dir_config *d = d_;
  
      d->qualify_redirect_url = flag ? AP_CORE_CONFIG_ON : AP_CORE_CONFIG_OFF;
  
      return NULL;
  }
  static const char *set_core_server_flag(cmd_parms *cmd, void *s_, int flag)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      return ap_set_flag_slot(cmd, conf, flag);
  }
  static const char *set_override_list(cmd_parms *cmd, void *d_, int argc, char *const argv[])
  {
      core_dir_config *d = d_;
      int i;
      const char *err;
  
      /* Throw a warning if we're in <Location> or <Files> */
      if (ap_check_cmd_context(cmd, NOT_IN_LOCATION | NOT_IN_FILES)) {
          ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00115)
                       "Useless use of AllowOverrideList at %s:%d",
                       cmd->directive->filename, cmd->directive->line_num);
      }
      if ((err = ap_check_cmd_context(cmd, NOT_IN_HTACCESS)) != NULL)
          return err;
  
      d->override_list = apr_table_make(cmd->pool, argc);
  
      for (i = 0; i < argc; i++) {
          if (!ap_cstr_casecmp(argv[i], "None")) {
              if (argc != 1) {
                  return "'None' not allowed with other directives in "
                         "AllowOverrideList";
              }
              return NULL;
          }
          else {
              const command_rec *result = NULL;
              module *mod = ap_top_module;
  
              result = ap_find_command_in_modules(argv[i], &mod);
              if (result == NULL) {
                  ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server,
                               APLOGNO(00116) "Discarding unrecognized "
                               "directive `%s' in AllowOverrideList at %s:%d",
                               argv[i], cmd->directive->filename,
                               cmd->directive->line_num);
                  continue;
              }
              else if ((result->req_override & (OR_ALL|ACCESS_CONF)) == 0) {
                  ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server,
                               APLOGNO(02304) "Discarding directive `%s' not "
                               "allowed in AllowOverrideList at %s:%d",
                               argv[i], cmd->directive->filename,
                               cmd->directive->line_num);
                  continue;
              }
              else {
                  apr_table_setn(d->override_list, argv[i], "1");
              }
          }
      }
  
      return NULL;
  }
  
  static const char *set_options(cmd_parms *cmd, void *d_, const char *l)
  {
      core_dir_config *d = d_;
      allow_options_t opt;
      int first = 1;
      int merge = 0;
      int all_none = 0;
      char action;
  
      while (l[0]) {
          char *w = ap_getword_conf(cmd->temp_pool, &l);
          action = '\0';
  
          if (*w == '+' || *w == '-') {
              action = *(w++);
              if (!merge && !first && !all_none) {
                  return "Either all Options must start with + or -, or no Option may.";
              }
              merge = 1;
          }
          else if (first) {
              d->opts = OPT_NONE;
          }
          else if (merge) {
              return "Either all Options must start with + or -, or no Option may.";
          }
  
          if (!ap_cstr_casecmp(w, "Indexes")) {
              opt = OPT_INDEXES;
          }
          else if (!ap_cstr_casecmp(w, "Includes")) {
              opt = (OPT_INCLUDES | OPT_INC_WITH_EXEC);
          }
          else if (!ap_cstr_casecmp(w, "IncludesNOEXEC")) {
              opt = OPT_INCLUDES;
          }
          else if (!ap_cstr_casecmp(w, "FollowSymLinks")) {
              opt = OPT_SYM_LINKS;
          }
          else if (!ap_cstr_casecmp(w, "SymLinksIfOwnerMatch")) {
              opt = OPT_SYM_OWNER;
          }
          else if (!ap_cstr_casecmp(w, "ExecCGI")) {
              opt = OPT_EXECCGI;
          }
          else if (!ap_cstr_casecmp(w, "MultiViews")) {
              opt = OPT_MULTI;
          }
          else if (!ap_cstr_casecmp(w, "RunScripts")) { /* AI backcompat. Yuck */
              opt = OPT_MULTI|OPT_EXECCGI;
          }
          else if (!ap_cstr_casecmp(w, "None")) {
              if (!first) {
                  return "'Options None' must be the first Option given.";
              }
              else if (merge) { /* Only works since None may not follow any other option. */
                  return "You may not use 'Options +None' or 'Options -None'.";
              }
              opt = OPT_NONE;
              all_none = 1;
          }
          else if (!ap_cstr_casecmp(w, "All")) {
              if (!first) {
                  return "'Options All' must be the first option given.";
              }
              else if (merge) { /* Only works since All may not follow any other option. */
                  return "You may not use 'Options +All' or 'Options -All'.";
              }
              opt = OPT_ALL;
              all_none = 1;
          }
          else {
              return apr_pstrcat(cmd->pool, "Illegal option ", w, NULL);
          }
  
          if ( (cmd->override_opts & opt) != opt ) {
              return apr_pstrcat(cmd->pool, "Option ", w, " not allowed here", NULL);
          }
          else if (action == '-') {
              /* we ensure the invariant (d->opts_add & d->opts_remove) == 0 */
              d->opts_remove |= opt;
              d->opts_add &= ~opt;
              d->opts &= ~opt;
          }
          else if (action == '+') {
              d->opts_add |= opt;
              d->opts_remove &= ~opt;
              d->opts |= opt;
          }
          else {
              d->opts |= opt;
          }
  
          first = 0;
      }
  
      return NULL;
  }
  
  static const char *set_default_type(cmd_parms *cmd, void *d_,
                                     const char *arg)
  {
      if (ap_cstr_casecmp(arg, "off") != 0 && ap_cstr_casecmp(arg, "none") != 0) {
          ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00117)
                "Ignoring deprecated use of DefaultType in line %d of %s.",
                       cmd->directive->line_num, cmd->directive->filename);
      }
  
      return NULL;
  }
  
  static const char *set_sethandler(cmd_parms *cmd,
                                       void *d_,
                                       const char *arg_)
  {
      core_dir_config *dirconf = d_;
      const char *err;
      dirconf->expr_handler = ap_expr_parse_cmd(cmd, arg_,
                                            AP_EXPR_FLAG_STRING_RESULT,
                                            &err, NULL);
      if (err) {
          return apr_pstrcat(cmd->pool,
                  "Can't parse expression : ", err, NULL);
      }
      return NULL;
  }
  
  /*
   * Note what data should be used when forming file ETag values.
   * It would be nicer to do this as an ITERATE, but then we couldn't
   * remember the +/- state properly.
   */
  static const char *set_etag_bits(cmd_parms *cmd, void *mconfig,
                                   const char *args_p)
  {
      core_dir_config *cfg;
      etag_components_t bit;
      char action;
      char *token;
      const char *args;
      int valid;
      int first;
      int explicit;
  
      cfg = (core_dir_config *)mconfig;
  
      args = args_p;
      first = 1;
      explicit = 0;
      while (args[0] != '\0') {
          action = '*';
          bit = ETAG_UNSET;
          valid = 1;
          token = ap_getword_conf(cmd->temp_pool, &args);
          if ((*token == '+') || (*token == '-')) {
              action = *token;
              token++;
          }
          else {
              /*
               * The occurrence of an absolute setting wipes
               * out any previous relative ones.  The first such
               * occurrence forgets any inherited ones, too.
               */
              if (first) {
                  cfg->etag_bits = ETAG_UNSET;
                  cfg->etag_add = ETAG_UNSET;
                  cfg->etag_remove = ETAG_UNSET;
                  first = 0;
              }
          }
  
          if (ap_cstr_casecmp(token, "None") == 0) {
              if (action != '*') {
                  valid = 0;
              }
              else {
                  cfg->etag_bits = bit = ETAG_NONE;
                  explicit = 1;
              }
          }
          else if (ap_cstr_casecmp(token, "All") == 0) {
              if (action != '*') {
                  valid = 0;
              }
              else {
                  explicit = 1;
                  cfg->etag_bits = bit = ETAG_ALL;
              }
          }
          else if (ap_cstr_casecmp(token, "Size") == 0) {
              bit = ETAG_SIZE;
          }
          else if ((ap_cstr_casecmp(token, "LMTime") == 0)
                   || (ap_cstr_casecmp(token, "MTime") == 0)
                   || (ap_cstr_casecmp(token, "LastModified") == 0)) {
              bit = ETAG_MTIME;
          }
          else if (ap_cstr_casecmp(token, "INode") == 0) {
              bit = ETAG_INODE;
          }
          else if (ap_cstr_casecmp(token, "Digest") == 0) {
              bit = ETAG_DIGEST;
          }
          else {
              return apr_pstrcat(cmd->pool, "Unknown keyword '",
                                 token, "' for ", cmd->cmd->name,
                                 " directive", NULL);
          }
  
          if (! valid) {
              return apr_pstrcat(cmd->pool, cmd->cmd->name, " keyword '",
                                 token, "' cannot be used with '+' or '-'",
                                 NULL);
          }
  
          if (action == '+') {
              /*
               * Make sure it's in the 'add' list and absent from the
               * 'subtract' list.
               */
              cfg->etag_add |= bit;
              cfg->etag_remove &= (~ bit);
          }
          else if (action == '-') {
              cfg->etag_remove |= bit;
              cfg->etag_add &= (~ bit);
          }
          else {
              /*
               * Non-relative values wipe out any + or - values
               * accumulated so far.
               */
              cfg->etag_bits |= bit;
              cfg->etag_add = ETAG_UNSET;
              cfg->etag_remove = ETAG_UNSET;
              explicit = 1;
          }
      }
  
      /*
       * Any setting at all will clear the 'None' and 'Unset' bits.
       */
  
      if (cfg->etag_add != ETAG_UNSET) {
          cfg->etag_add &= (~ ETAG_UNSET);
      }
  
      if (cfg->etag_remove != ETAG_UNSET) {
          cfg->etag_remove &= (~ ETAG_UNSET);
      }
  
      if (explicit) {
          cfg->etag_bits &= (~ ETAG_UNSET);
  
          if ((cfg->etag_bits & ETAG_NONE) != ETAG_NONE) {
              cfg->etag_bits &= (~ ETAG_NONE);
          }
      }
  
      return NULL;
  }
  
  static const char *set_enable_mmap(cmd_parms *cmd, void *d_,
                                     const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "on") == 0) {
          d->enable_mmap = ENABLE_MMAP_ON;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          d->enable_mmap = ENABLE_MMAP_OFF;
      }
      else {
          return "parameter must be 'on' or 'off'";
      }
  
      return NULL;
  }
  
  static const char *set_enable_sendfile(cmd_parms *cmd, void *d_,
                                     const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "on") == 0) {
          d->enable_sendfile = ENABLE_SENDFILE_ON;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          d->enable_sendfile = ENABLE_SENDFILE_OFF;
      }
      else {
          return "parameter must be 'on' or 'off'";
      }
  
      return NULL;
  }
  
  static const char *set_read_buf_size(cmd_parms *cmd, void *d_,
                                       const char *arg)
  {
      core_dir_config *d = d_;
      apr_off_t size;
      char *end;
  
      if (apr_strtoff(&size, arg, &end, 10)
              || *end || size < 0 || size > APR_UINT32_MAX)
          return apr_pstrcat(cmd->pool,
                             "parameter must be a number between 0 and "
                             APR_STRINGIFY(APR_UINT32_MAX) "): ",
                             arg, NULL);
  
      d->read_buf_size = (apr_size_t)size;
  
      return NULL;
  }
  
  static const char *set_flush_max_threshold(cmd_parms *cmd, void *d_,
                                             const char *arg)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      apr_off_t size;
      char *end;
  
      if (apr_strtoff(&size, arg, &end, 10)
              || *end || size < 0 || size > APR_UINT32_MAX)
          return apr_pstrcat(cmd->pool,
                             "parameter must be a number between 0 and "
                             APR_STRINGIFY(APR_UINT32_MAX) "): ",
                             arg, NULL);
  
      conf->flush_max_threshold = (apr_size_t)size;
  
      return NULL;
  }
  
  static const char *set_flush_max_pipelined(cmd_parms *cmd, void *d_,
                                             const char *arg)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      apr_off_t num;
      char *end;
  
      if (apr_strtoff(&num, arg, &end, 10)
              || *end || num < -1 || num > APR_INT32_MAX)
          return apr_pstrcat(cmd->pool,
                             "parameter must be a number between -1 and "
                             APR_STRINGIFY(APR_INT32_MAX) ": ",
                             arg, NULL);
  
      conf->flush_max_pipelined = (apr_int32_t)num;
  
      return NULL;
  }
  
  /*
   * Report a missing-'>' syntax error.
   */
  static char *unclosed_directive(cmd_parms *cmd)
  {
      return apr_pstrcat(cmd->pool, cmd->cmd->name,
                         "> directive missing closing '>'", NULL);
  }
  
  /*
   * Report a missing args in '<Foo >' syntax error.
   */
  static char *missing_container_arg(cmd_parms *cmd)
  {
      return apr_pstrcat(cmd->pool, cmd->cmd->name,
                         "> directive requires additional arguments", NULL);
  }
  
  AP_CORE_DECLARE_NONSTD(const char *) ap_limit_section(cmd_parms *cmd,
                                                        void *dummy,
                                                        const char *arg)
  {
      const char *endp = ap_strrchr_c(arg, '>');
      const char *limited_methods;
      void *tog = cmd->cmd->cmd_data;
      apr_int64_t limited = 0;
      apr_int64_t old_limited = cmd->limited;
      const char *errmsg;
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      limited_methods = apr_pstrmemdup(cmd->temp_pool, arg, endp - arg);
  
      if (!limited_methods[0]) {
          return missing_container_arg(cmd);
      }
  
      while (limited_methods[0]) {
          char *method = ap_getword_conf(cmd->temp_pool, &limited_methods);
          int methnum;
  
          /* check for builtin or module registered method number */
          methnum = ap_method_number_of(method);
  
          if (methnum == M_TRACE && !tog) {
              return "TRACE cannot be controlled by <Limit>, see TraceEnable";
          }
          else if (methnum == M_INVALID) {
              /* method has not been registered yet, but resource restriction
               * is always checked before method handling, so register it.
               */
              if (cmd->pool == cmd->temp_pool) {
                  /* In .htaccess, we can't globally register new methods. */
                  return apr_psprintf(cmd->pool, "Could not register method '%s' "
                                     "for %s from .htaccess configuration",
                                      method, cmd->cmd->name);
              }
              methnum = ap_method_register(cmd->pool,
                                           apr_pstrdup(cmd->pool, method));
          }
  
          limited |= (AP_METHOD_BIT << methnum);
      }
  
      /* Killing two features with one function,
       * if (tog == NULL) <Limit>, else <LimitExcept>
       */
      limited = tog ? ~limited : limited;
  
      if (!(old_limited & limited)) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name,
                             "> directive excludes all methods", NULL);
      }
      else if ((old_limited & limited) == old_limited) {
          return apr_pstrcat(cmd->pool, cmd->cmd->name,
                             "> directive specifies methods already excluded",
                             NULL);
      }
  
      cmd->limited &= limited;
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd, cmd->context);
  
      cmd->limited = old_limited;
  
      return errmsg;
  }
  
  /* XXX: Bogus - need to do this differently (at least OS2/Netware suffer
   * the same problem!!!
   * We use this in <DirectoryMatch> and <FilesMatch>, to ensure that
   * people don't get bitten by wrong-cased regex matches
   */
  
  #ifdef WIN32
  #define USE_ICASE AP_REG_ICASE
  #else
  #define USE_ICASE 0
  #endif
  
  static const char *dirsection(cmd_parms *cmd, void *mconfig, const char *arg)
  {
      const char *errmsg;
      const char *endp = ap_strrchr_c(arg, '>');
      int old_overrides = cmd->override;
      char *old_path = cmd->path;
      core_dir_config *conf;
      ap_conf_vector_t *new_dir_conf = ap_create_per_dir_config(cmd->pool);
      ap_regex_t *r = NULL;
      const command_rec *thiscmd = cmd->cmd;
  
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrndup(cmd->temp_pool, arg, endp - arg);
  
      if (!arg[0]) {
          return missing_container_arg(cmd);
      }
  
      cmd->path = ap_getword_conf(cmd->pool, &arg);
      cmd->override = OR_ALL|ACCESS_CONF;
  
      if (!strcmp(cmd->path, "~")) {
          cmd->path = ap_getword_conf(cmd->pool, &arg);
          if (!cmd->path)
              return "<Directory ~ > block must specify a path";
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED|USE_ICASE);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
      else if (thiscmd->cmd_data) { /* <DirectoryMatch> */
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED|USE_ICASE);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
      else if (strcmp(cmd->path, "/") != 0)
      {
          int run_mode = ap_state_query(AP_SQ_RUN_MODE);
          char *newpath;
  
          /*
           * Ensure that the pathname is canonical, and append the trailing /
           */
          apr_status_t rv = apr_filepath_merge(&newpath, NULL, cmd->path,
                                               APR_FILEPATH_TRUENAME, cmd->pool);
          if (rv != APR_SUCCESS && rv != APR_EPATHWILD) {
              return apr_pstrcat(cmd->pool, "<Directory \"", cmd->path,
                                 "\"> path is invalid.", NULL);
          }
  
          if (run_mode == AP_SQ_RM_CONFIG_TEST &&
              !ap_is_directory(cmd->temp_pool, cmd->path)) {
              ap_log_perror(APLOG_MARK, APLOG_STARTUP, 0,
                            cmd->temp_pool, APLOGNO(10234)
                            "Warning: <Directory \"%s\"> does not exist or is not a directory",
                            cmd->path);
          }
  
          cmd->path = newpath;
          if (cmd->path[strlen(cmd->path) - 1] != '/')
              cmd->path = apr_pstrcat(cmd->pool, cmd->path, "/", NULL);
      }
  
      /* initialize our config and fetch it */
      conf = ap_set_config_vectors(cmd->server, new_dir_conf, cmd->path,
                                   &core_module, cmd->pool);
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd, new_dir_conf);
      if (errmsg != NULL)
          return errmsg;
  
      conf->r = r;
      conf->d = cmd->path;
      conf->d_is_fnmatch = (apr_fnmatch_test(conf->d) != 0);
  
      if (r) {
          conf->refs = apr_array_make(cmd->pool, 8, sizeof(char *));
          ap_regname(r, conf->refs, AP_REG_MATCH, 1);
      }
  
      /* Make this explicit - the "/" root has 0 elements, that is, we
       * will always merge it, and it will always sort and merge first.
       * All others are sorted and tested by the number of slashes.
       */
      if (strcmp(conf->d, "/") == 0)
          conf->d_components = 0;
      else
          conf->d_components = ap_count_dirs(conf->d);
  
      ap_add_per_dir_conf(cmd->server, new_dir_conf);
  
      if (*arg != '\0') {
          return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                             "> arguments not (yet) supported.", NULL);
      }
  
      cmd->path = old_path;
      cmd->override = old_overrides;
  
      return NULL;
  }
  
  static const char *urlsection(cmd_parms *cmd, void *mconfig, const char *arg)
  {
      const char *errmsg;
      const char *endp = ap_strrchr_c(arg, '>');
      int old_overrides = cmd->override;
      char *old_path = cmd->path;
      core_dir_config *conf;
      ap_regex_t *r = NULL;
      const command_rec *thiscmd = cmd->cmd;
      ap_conf_vector_t *new_url_conf = ap_create_per_dir_config(cmd->pool);
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrndup(cmd->temp_pool, arg, endp - arg);
  
      if (!arg[0]) {
          return missing_container_arg(cmd);
      }
  
      cmd->path = ap_getword_conf(cmd->pool, &arg);
      cmd->override = OR_ALL|ACCESS_CONF;
  
      if (thiscmd->cmd_data) { /* <LocationMatch> */
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
      else if (!strcmp(cmd->path, "~")) {
          cmd->path = ap_getword_conf(cmd->pool, &arg);
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
  
      /* initialize our config and fetch it */
      conf = ap_set_config_vectors(cmd->server, new_url_conf, cmd->path,
                                   &core_module, cmd->pool);
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd, new_url_conf);
      if (errmsg != NULL)
          return errmsg;
  
      conf->d = apr_pstrdup(cmd->pool, cmd->path);     /* No mangling, please */
      conf->d_is_fnmatch = apr_fnmatch_test(conf->d) != 0;
      conf->r = r;
  
      if (r) {
          conf->refs = apr_array_make(cmd->pool, 8, sizeof(char *));
          ap_regname(r, conf->refs, AP_REG_MATCH, 1);
      }
  
      ap_add_per_url_conf(cmd->server, new_url_conf);
  
      if (*arg != '\0') {
          return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                             "> arguments not (yet) supported.", NULL);
      }
  
      cmd->path = old_path;
      cmd->override = old_overrides;
  
      return NULL;
  }
  
  static const char *filesection(cmd_parms *cmd, void *mconfig, const char *arg)
  {
      const char *errmsg;
      const char *endp = ap_strrchr_c(arg, '>');
      int old_overrides = cmd->override;
      char *old_path = cmd->path;
      core_dir_config *conf;
      ap_regex_t *r = NULL;
      const command_rec *thiscmd = cmd->cmd;
      ap_conf_vector_t *new_file_conf = ap_create_per_dir_config(cmd->pool);
      const char *err = ap_check_cmd_context(cmd,
                                             NOT_IN_LOCATION | NOT_IN_LIMIT);
  
      if (err != NULL) {
          return err;
      }
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrndup(cmd->temp_pool, arg, endp - arg);
  
      if (!arg[0]) {
          return missing_container_arg(cmd);
      }
  
      cmd->path = ap_getword_conf(cmd->pool, &arg);
      /* Only if not an .htaccess file */
      if (!old_path) {
          cmd->override = OR_ALL|ACCESS_CONF;
      }
  
      if (thiscmd->cmd_data) { /* <FilesMatch> */
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED|USE_ICASE);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
      else if (!strcmp(cmd->path, "~")) {
          cmd->path = ap_getword_conf(cmd->pool, &arg);
          r = ap_pregcomp(cmd->pool, cmd->path, AP_REG_EXTENDED|USE_ICASE);
          if (!r) {
              return "Regex could not be compiled";
          }
      }
      else {
          char *newpath;
          /* Ensure that the pathname is canonical, but we
           * can't test the case/aliases without a fixed path */
          if (apr_filepath_merge(&newpath, "", cmd->path,
                                 0, cmd->pool) != APR_SUCCESS)
                  return apr_pstrcat(cmd->pool, "<Files \"", cmd->path,
                                 "\"> is invalid.", NULL);
          cmd->path = newpath;
      }
  
      /* initialize our config and fetch it */
      conf = ap_set_config_vectors(cmd->server, new_file_conf, cmd->path,
                                   &core_module, cmd->pool);
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd, new_file_conf);
      if (errmsg != NULL)
          return errmsg;
  
      conf->d = cmd->path;
      conf->d_is_fnmatch = apr_fnmatch_test(conf->d) != 0;
      conf->r = r;
  
      if (r) {
          conf->refs = apr_array_make(cmd->pool, 8, sizeof(char *));
          ap_regname(r, conf->refs, AP_REG_MATCH, 1);
      }
  
      ap_add_file_conf(cmd->pool, (core_dir_config *)mconfig, new_file_conf);
  
      if (*arg != '\0') {
          return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                             "> arguments not (yet) supported.", NULL);
      }
  
      cmd->path = old_path;
      cmd->override = old_overrides;
  
      return NULL;
  }
  
  #define COND_IF      ((void *)1)
  #define COND_ELSE    ((void *)2)
  #define COND_ELSEIF  ((void *)3)
  
  static const char *ifsection(cmd_parms *cmd, void *mconfig, const char *arg)
  {
      const char *errmsg;
      const char *endp = ap_strrchr_c(arg, '>');
      int old_overrides = cmd->override;
      char *old_path = cmd->path;
      core_dir_config *conf;
      const command_rec *thiscmd = cmd->cmd;
      ap_conf_vector_t *new_if_conf = ap_create_per_dir_config(cmd->pool);
      const char *err = ap_check_cmd_context(cmd, NOT_IN_LIMIT);
      const char *condition;
      const char *expr_err;
  
      if (err != NULL) {
          return err;
      }
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrndup(cmd->temp_pool, arg, endp - arg);
  
      /*
       * Set a dummy value so that other directives notice that they are inside
       * a config section.
       */
      cmd->path = "*If";
      /* Only if not an .htaccess file */
      if (!old_path) {
          cmd->override = OR_ALL|ACCESS_CONF;
      }
  
      /* initialize our config and fetch it */
      conf = ap_set_config_vectors(cmd->server, new_if_conf, cmd->path,
                                   &core_module, cmd->pool);
  
      if (cmd->cmd->cmd_data == COND_IF)
          conf->condition_ifelse = AP_CONDITION_IF;
      else if (cmd->cmd->cmd_data == COND_ELSEIF)
          conf->condition_ifelse = AP_CONDITION_ELSEIF;
      else if (cmd->cmd->cmd_data == COND_ELSE)
          conf->condition_ifelse = AP_CONDITION_ELSE;
      else
          ap_assert(0);
  
      if (conf->condition_ifelse == AP_CONDITION_ELSE) {
          if (arg[0])
              return "<Else> does not take an argument";
      }
      else {
          if (!arg[0])
              return missing_container_arg(cmd);
          condition = ap_getword_conf(cmd->pool, &arg);
          conf->condition = ap_expr_parse_cmd(cmd, condition, 0, &expr_err, NULL);
          if (expr_err)
              return apr_psprintf(cmd->pool, "Cannot parse condition clause: %s",
                                  expr_err);
      }
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd, new_if_conf);
      if (errmsg != NULL)
          return errmsg;
  
      conf->d = cmd->path;
      conf->d_is_fnmatch = 0;
      conf->r = NULL;
  
      errmsg = ap_add_if_conf(cmd->pool, (core_dir_config *)mconfig, new_if_conf);
      if (errmsg != NULL)
          return errmsg;
  
      if (*arg != '\0') {
          return apr_pstrcat(cmd->pool, "Multiple ", thiscmd->name,
                             "> arguments not supported.", NULL);
      }
  
      cmd->path = old_path;
      cmd->override = old_overrides;
  
      return NULL;
  }
  
  static module *find_module(server_rec *s, const char *name)
  {
      module *found = ap_find_linked_module(name);
  
      /* search prelinked stuff */
      if (!found) {
          ap_module_symbol_t *current = ap_prelinked_module_symbols;
  
          for (; current->name; ++current) {
              if (!strcmp(current->name, name)) {
                  found = current->modp;
                  break;
              }
          }
      }
  
      /* search dynamic stuff */
      if (!found) {
          APR_OPTIONAL_FN_TYPE(ap_find_loaded_module_symbol) *check_symbol =
              APR_RETRIEVE_OPTIONAL_FN(ap_find_loaded_module_symbol);
  
          if (check_symbol) {
              /*
               * There are two phases where calling ap_find_loaded_module_symbol
               * is problematic:
               *
               * During reading of the config, ap_server_conf is invalid but s
               * points to the main server config, if passed from cmd->server
               * of an EXEC_ON_READ directive.
               *
               * During config parsing, s may be a virtual host that would cause
               * a segfault in mod_so if passed to ap_find_loaded_module_symbol,
               * because mod_so's server config for vhosts is initialized later.
               * But ap_server_conf is already set at this time.
               *
               * Therefore we use s if it is not virtual and ap_server_conf if
               * s is virtual.
               */
              found = check_symbol(s->is_virtual ? ap_server_conf : s, name);
          }
      }
  
      return found;
  }
  
  /* Callback function type used by start_cond_section. */
  typedef int (*test_cond_section_fn)(cmd_parms *cmd, const char *arg);
  
  /* Implementation of <IfXXXXX>-style conditional sections.  Callback
   * to test condition must be in cmd->info, matching function type
   * test_cond_section_fn. */
  static const char *start_cond_section(cmd_parms *cmd, void *mconfig, const char *arg)
  {
      const char *endp = ap_strrchr_c(arg, '>');
      int result, not = (arg[0] == '!');
      test_cond_section_fn testfn = (test_cond_section_fn)cmd->info;
      const char *arg1;
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrmemdup(cmd->temp_pool, arg, endp - arg);
  
      if (not) {
          arg++;
      }
  
      arg1 = ap_getword_conf(cmd->temp_pool, &arg);
  
      if (!arg1[0]) {
          return missing_container_arg(cmd);
      }
  
      result = testfn(cmd, arg1);
  
      if ((!not && result) || (not && !result)) {
          ap_directive_t *parent = NULL;
          ap_directive_t *current = NULL;
          const char *retval;
  
          retval = ap_build_cont_config(cmd->pool, cmd->temp_pool, cmd,
                                        &current, &parent, cmd->cmd->name);
          *(ap_directive_t **)mconfig = current;
          return retval;
      }
      else {
          *(ap_directive_t **)mconfig = NULL;
          return ap_soak_end_container(cmd, cmd->cmd->name);
      }
  }
  
  /* Callback to implement <IfModule> test for start_cond_section. */
  static int test_ifmod_section(cmd_parms *cmd, const char *arg)
  {
      return find_module(cmd->server, arg) != NULL;
  }
  
  AP_DECLARE(int) ap_exists_config_define(const char *name)
  {
      return ap_array_str_contains(ap_server_config_defines, name);
  }
  
  static int test_ifdefine_section(cmd_parms *cmd, const char *arg)
  {
      return ap_exists_config_define(arg);
  }
  
  static int test_iffile_section(cmd_parms *cmd, const char *arg)
  {
      const char *relative;
      apr_finfo_t sb;
  
      /*
       * At least on Windows, if the path we are testing is not valid (for example
       * a path on a USB key that is not plugged), 'ap_server_root_relative()' will
       * return NULL. In such a case, consider that the file is not there and that
       * the section should be skipped.
       */
      relative = ap_server_root_relative(cmd->temp_pool, arg);
      return (relative &&
             (apr_stat(&sb, relative, APR_FINFO_TYPE, cmd->temp_pool) == APR_SUCCESS));
  }
  
  static int test_ifdirective_section(cmd_parms *cmd, const char *arg)
  {
      return ap_exists_directive(cmd->temp_pool, arg);
  }
  
  static int test_ifsection_section(cmd_parms *cmd, const char *arg)
  {
      const char *name = apr_pstrcat(cmd->temp_pool, "<", arg, NULL);
      return ap_exists_directive(cmd->temp_pool, name);
  }
  
  /* httpd.conf commands... beginning with the <VirtualHost> business */
  
  static const char *virtualhost_section(cmd_parms *cmd, void *dummy,
                                         const char *arg)
  {
      server_rec *main_server = cmd->server, *s;
      const char *errmsg;
      const char *endp = ap_strrchr_c(arg, '>');
      apr_pool_t *p = cmd->pool;
  
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      if (endp == NULL) {
          return unclosed_directive(cmd);
      }
  
      arg = apr_pstrndup(cmd->temp_pool, arg, endp - arg);
  
      if (!arg[0]) {
          return missing_container_arg(cmd);
      }
  
      /* FIXME: There's another feature waiting to happen here -- since you
          can now put multiple addresses/names on a single <VirtualHost>
          you might want to use it to group common definitions and then
          define other "subhosts" with their individual differences.  But
          personally I'd rather just do it with a macro preprocessor. -djg */
      if (main_server->is_virtual) {
          return "<VirtualHost> doesn't nest!";
      }
  
      errmsg = ap_init_virtual_host(p, arg, main_server, &s);
      if (errmsg) {
          return errmsg;
      }
  
      s->next = main_server->next;
      main_server->next = s;
  
      s->defn_name = cmd->directive->filename;
      s->defn_line_number = cmd->directive->line_num;
  
      cmd->server = s;
  
      errmsg = ap_walk_config(cmd->directive->first_child, cmd,
                              s->lookup_defaults);
  
      cmd->server = main_server;
  
      return errmsg;
  }
  
  static const char *set_regex_default_options(cmd_parms *cmd,
                                               void *dummy,
                                               const char *arg)
  {
      const command_rec *thiscmd = cmd->cmd;
      int cflags, cflag;
  
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL) {
          return err;
      }
  
      cflags = ap_regcomp_get_default_cflags();
      while (*arg) {
          const char *name = ap_getword_conf(cmd->pool, &arg);
          int how = 0;
  
          if (strcasecmp(name, "none") == 0) {
              cflags = 0;
              continue;
          }
  
          if (*name == '+') {
              name++;
              how = +1;
          }
          else if (*name == '-') {
              name++;
              how = -1;
          }
  
          cflag = ap_regcomp_default_cflag_by_name(name);
          if (!cflag) {
              return apr_psprintf(cmd->pool, "%s: option '%s' unknown",
                                  thiscmd->name, name);
          }
  
          if (how > 0) {
              cflags |= cflag;
          }
          else if (how < 0) {
              cflags &= ~cflag;
          }
          else {
              cflags = cflag;
          }
      }
      ap_regcomp_set_default_cflags(cflags);
  
      return NULL;
  }
  
  static const char *set_server_alias(cmd_parms *cmd, void *dummy,
                                      const char *arg)
  {
      if (!cmd->server->names) {
          return "ServerAlias only used in <VirtualHost>";
      }
  
      while (*arg) {
          char **item, *name = ap_getword_conf(cmd->pool, &arg);
  
          if (ap_is_matchexp(name)) {
              item = (char **)apr_array_push(cmd->server->wild_names);
          }
          else {
              item = (char **)apr_array_push(cmd->server->names);
          }
  
          *item = name;
      }
  
      return NULL;
  }
  
  static const char *set_accf_map(cmd_parms *cmd, void *dummy,
                                  const char *iproto, const char* iaccf)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      char* proto;
      char* accf;
      if (err != NULL) {
          return err;
      }
  
      proto = apr_pstrdup(cmd->pool, iproto);
      ap_str_tolower(proto);
      accf = apr_pstrdup(cmd->pool, iaccf);
      ap_str_tolower(accf);
      apr_table_setn(conf->accf_map, proto, accf);
  
      return NULL;
  }
  
  AP_DECLARE(const char*) ap_get_server_protocol(server_rec* s)
  {
      core_server_config *conf = ap_get_core_module_config(s->module_config);
      return conf->protocol;
  }
  
  AP_DECLARE(void) ap_set_server_protocol(server_rec* s, const char* proto)
  {
      core_server_config *conf = ap_get_core_module_config(s->module_config);
      conf->protocol = proto;
  }
  
  static const char *set_protocol(cmd_parms *cmd, void *dummy,
                                  const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      char* proto;
  
      if (err != NULL) {
          return err;
      }
  
      proto = apr_pstrdup(cmd->pool, arg);
      ap_str_tolower(proto);
      conf->protocol = proto;
  
      return NULL;
  }
  
  static const char *set_server_string_slot(cmd_parms *cmd, void *dummy,
                                            const char *arg)
  {
      /* This one's pretty generic... */
  
      int offset = (int)(long)cmd->info;
      char *struct_ptr = (char *)cmd->server;
  
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      if (err != NULL) {
          return err;
      }
  
      *(const char **)(struct_ptr + offset) = arg;
      return NULL;
  }
  
  /*
   * The ServerName directive takes one argument with format
   * [scheme://]fully-qualified-domain-name[:port], for instance
   * ServerName www.example.com
   * ServerName www.example.com:80
   * ServerName https://www.example.com:443
   */
  
  static const char *server_hostname_port(cmd_parms *cmd, void *dummy, const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      const char *portstr, *part;
      char *scheme;
      int port;
  
      if (err != NULL) {
          return err;
      }
  
      if (apr_fnmatch_test(arg))
          return apr_pstrcat(cmd->temp_pool, "Invalid ServerName \"", arg,
                  "\" use ServerAlias to set multiple server names.", NULL);
  
      part = ap_strstr_c(arg, "://");
  
      if (part) {
        scheme = apr_pstrndup(cmd->pool, arg, part - arg);
        ap_str_tolower(scheme);
        cmd->server->server_scheme = (const char *)scheme;
        part += 3;
      } else {
        part = arg;
      }
  
      portstr = ap_strchr_c(part, ':');
      if (portstr) {
          cmd->server->server_hostname = apr_pstrndup(cmd->pool, part,
                                                      portstr - part);
          portstr++;
          port = atoi(portstr);
          if (port <= 0 || port >= 65536) { /* 65536 == 1<<16 */
              return apr_pstrcat(cmd->temp_pool, "The port number \"", arg,
                            "\" is outside the appropriate range "
                            "(i.e., 1..65535).", NULL);
          }
      }
      else {
          cmd->server->server_hostname = apr_pstrdup(cmd->pool, part);
          port = 0;
      }
  
      cmd->server->port = port;
      return NULL;
  }
  
  static const char *set_signature_flag(cmd_parms *cmd, void *d_,
                                        const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "On") == 0) {
          d->server_signature = srv_sig_on;
      }
      else if (ap_cstr_casecmp(arg, "Off") == 0) {
          d->server_signature = srv_sig_off;
      }
      else if (ap_cstr_casecmp(arg, "EMail") == 0) {
          d->server_signature = srv_sig_withmail;
      }
      else {
          return "ServerSignature: use one of: off | on | email";
      }
  
      return NULL;
  }
  
  static const char *set_server_root(cmd_parms *cmd, void *dummy,
                                     const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
  
      if (err != NULL) {
          return err;
      }
  
      if ((apr_filepath_merge((char**)&ap_server_root, NULL, arg,
                              APR_FILEPATH_TRUENAME, cmd->pool) != APR_SUCCESS)
          || !ap_is_directory(cmd->temp_pool, ap_server_root)) {
          return "ServerRoot must be a valid directory";
      }
  
      return NULL;
  }
  
  static const char *set_runtime_dir(cmd_parms *cmd, void *dummy, const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
  
      if (err != NULL) {
          return err;
      }
  
      if ((apr_filepath_merge((char**)&ap_runtime_dir, NULL,
                              ap_server_root_relative(cmd->temp_pool, arg),
                              APR_FILEPATH_TRUENAME, cmd->pool) != APR_SUCCESS)
          || !ap_is_directory(cmd->temp_pool, ap_runtime_dir)) {
          return "DefaultRuntimeDir must be a valid directory, absolute or relative to ServerRoot";
      }
  
      return NULL;
  }
  
  static const char *set_state_dir(cmd_parms *cmd, void *dummy, const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
  
      if (err != NULL) {
          return err;
      }
  
      if ((apr_filepath_merge((char**)&core_state_dir, NULL,
                              ap_server_root_relative(cmd->temp_pool, arg),
                              APR_FILEPATH_TRUENAME, cmd->pool) != APR_SUCCESS)
          || !ap_is_directory(cmd->temp_pool, core_state_dir)) {
          return "DefaultStateDir must be a valid directory, absolute or relative to ServerRoot";
      }
  
      return NULL;
  }
  
  static const char *set_timeout(cmd_parms *cmd, void *dummy, const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
  
      if (err != NULL) {
          return err;
      }
  
      cmd->server->timeout = apr_time_from_sec(atoi(arg));
      return NULL;
  }
  
  static const char *set_allow2f(cmd_parms *cmd, void *d_, const char *arg)
  {
      core_dir_config *d = d_;
  
      if (0 == ap_cstr_casecmp(arg, "on")) {
          d->allow_encoded_slashes = 1;
          d->decode_encoded_slashes = 1; /* for compatibility with 2.0 & 2.2 */
      } else if (0 == ap_cstr_casecmp(arg, "off")) {
          d->allow_encoded_slashes = 0;
          d->decode_encoded_slashes = 0;
      } else if (0 == ap_cstr_casecmp(arg, "nodecode")) {
          d->allow_encoded_slashes = 1;
          d->decode_encoded_slashes = 0;
      } else {
          return apr_pstrcat(cmd->pool,
                             cmd->cmd->name, " must be On, Off, or NoDecode",
                             NULL);
      }
  
      d->allow_encoded_slashes_set = 1;
      d->decode_encoded_slashes_set = 1;
  
      return NULL;
  }
  
  static const char *set_hostname_lookups(cmd_parms *cmd, void *d_,
                                          const char *arg)
  {
      core_dir_config *d = d_;
  
      if (!ap_cstr_casecmp(arg, "on")) {
          d->hostname_lookups = HOSTNAME_LOOKUP_ON;
      }
      else if (!ap_cstr_casecmp(arg, "off")) {
          d->hostname_lookups = HOSTNAME_LOOKUP_OFF;
      }
      else if (!ap_cstr_casecmp(arg, "double")) {
          d->hostname_lookups = HOSTNAME_LOOKUP_DOUBLE;
      }
      else {
          return "parameter must be 'on', 'off', or 'double'";
      }
  
      return NULL;
  }
  
  static const char *set_serverpath(cmd_parms *cmd, void *dummy,
                                    const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
  
      if (err != NULL) {
          return err;
      }
  
      cmd->server->path = arg;
      cmd->server->pathlen = (int)strlen(arg);
      return NULL;
  }
  
  static const char *set_accept_path_info(cmd_parms *cmd, void *d_, const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "on") == 0) {
          d->accept_path_info = AP_REQ_ACCEPT_PATH_INFO;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          d->accept_path_info = AP_REQ_REJECT_PATH_INFO;
      }
      else if (ap_cstr_casecmp(arg, "default") == 0) {
          d->accept_path_info = AP_REQ_DEFAULT_PATH_INFO;
      }
      else {
          return "AcceptPathInfo must be set to on, off or default";
      }
  
      return NULL;
  }
  
  static const char *set_use_canonical_name(cmd_parms *cmd, void *d_,
                                            const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "on") == 0) {
          d->use_canonical_name = USE_CANONICAL_NAME_ON;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          d->use_canonical_name = USE_CANONICAL_NAME_OFF;
      }
      else if (ap_cstr_casecmp(arg, "dns") == 0) {
          d->use_canonical_name = USE_CANONICAL_NAME_DNS;
      }
      else {
          return "parameter must be 'on', 'off', or 'dns'";
      }
  
      return NULL;
  }
  
  static const char *set_use_canonical_phys_port(cmd_parms *cmd, void *d_,
                                            const char *arg)
  {
      core_dir_config *d = d_;
  
      if (ap_cstr_casecmp(arg, "on") == 0) {
          d->use_canonical_phys_port = USE_CANONICAL_PHYS_PORT_ON;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          d->use_canonical_phys_port = USE_CANONICAL_PHYS_PORT_OFF;
      }
      else {
          return "parameter must be 'on' or 'off'";
      }
  
      return NULL;
  }
  
  static const char *include_config (cmd_parms *cmd, void *dummy,
                                     const char *name)
  {
      ap_directive_t *conftree = NULL;
      const char *conffile, *error;
      unsigned *recursion;
      int optional = cmd->cmd->cmd_data ? 1 : 0;
      void *data;
  
      /* NOTE: ap_include_sentinel is also used by ap_process_resource_config()
       * during DUMP_INCLUDES; don't change its type or remove it without updating
       * the other.
       */
      apr_pool_userdata_get(&data, "ap_include_sentinel", cmd->pool);
      if (data) {
          recursion = data;
      }
      else {
          data = recursion = apr_palloc(cmd->pool, sizeof(*recursion));
          *recursion = 0;
          apr_pool_userdata_setn(data, "ap_include_sentinel", NULL, cmd->pool);
      }
  
      if (++*recursion > AP_MAX_INCLUDE_DEPTH) {
          *recursion = 0;
          return apr_psprintf(cmd->pool, "Exceeded maximum include depth of %u, "
                              "There appears to be a recursion.",
                              AP_MAX_INCLUDE_DEPTH);
      }
  
      conffile = ap_server_root_relative(cmd->pool, name);
      if (!conffile) {
          *recursion = 0;
          return apr_pstrcat(cmd->pool, "Invalid Include path ",
                             name, NULL);
      }
  
      if (ap_exists_config_define("DUMP_INCLUDES")) {
          unsigned *line_number;
  
          /* NOTE: ap_include_lineno is used by ap_process_resource_config()
           * during DUMP_INCLUDES; don't change its type or remove it without
           * updating the other.
           */
          apr_pool_userdata_get(&data, "ap_include_lineno", cmd->pool);
          if (data) {
              line_number = data;
          } else {
              data = line_number = apr_palloc(cmd->pool, sizeof(*line_number));
              apr_pool_userdata_setn(data, "ap_include_lineno", NULL, cmd->pool);
          }
  
          *line_number = cmd->config_file->line_number;
      }
  
      error = ap_process_fnmatch_configs(cmd->server, conffile, &conftree,
                                         cmd->pool, cmd->temp_pool,
                                         optional);
      if (error) {
          *recursion = 0;
          return error;
      }
  
      *(ap_directive_t **)dummy = conftree;
  
      /* recursion level done */
      if (*recursion) {
          --*recursion;
      }
  
      return NULL;
  }
  
  static const char *update_loglevel(cmd_parms *cmd, struct ap_logconf *log,
                                     const char *arg)
  {
      const char *level_str, *err;
      module *module;
      int level;
  
      level_str = ap_strrchr_c(arg, ':');
  
      if (level_str == NULL) {
          err = ap_parse_log_level(arg, &log->level);
          if (err != NULL)
              return err;
          ap_reset_module_loglevels(log, APLOG_NO_MODULE);
          ap_log_error(APLOG_MARK, APLOG_TRACE3, 0, cmd->server,
                       "Setting %s for all modules to %s", cmd->cmd->name, arg);
          return NULL;
      }
  
      arg = apr_pstrmemdup(cmd->temp_pool, arg, level_str - arg);
      level_str++;
      if (!*level_str) {
          return apr_psprintf(cmd->temp_pool, "Module specifier '%s' must be "
                              "followed by a log level keyword", arg);
      }
  
      err = ap_parse_log_level(level_str, &level);
      if (err != NULL)
          return apr_psprintf(cmd->temp_pool, "%s:%s: %s", arg, level_str, err);
  
      if ((module = find_module(cmd->server, arg)) == NULL) {
          char *name = apr_psprintf(cmd->temp_pool, "%s_module", arg);
          ap_log_error(APLOG_MARK, APLOG_TRACE6, 0, cmd->server,
                       "Cannot find module '%s', trying '%s'", arg, name);
          module = find_module(cmd->server, name);
      }
  
      if (module == NULL) {
          return apr_psprintf(cmd->temp_pool, "Cannot find module %s", arg);
      }
  
      ap_set_module_loglevel(cmd->pool, log, module->module_index, level);
      ap_log_error(APLOG_MARK, APLOG_TRACE3, 0, cmd->server,
                   "Setting %s for module %s to %s", cmd->cmd->name,
                   module->name, level_str);
  
      return NULL;
  }
  
  static const char *set_loglevel(cmd_parms *cmd, void *config_, const char *arg)
  {
      struct ap_logconf *log;
  
      if (cmd->path) {
          core_dir_config *dconf = config_;
          if (!dconf->log) {
              dconf->log = ap_new_log_config(cmd->pool, NULL);
          }
          log = dconf->log;
      }
      else {
          log = &cmd->server->log;
      }
  
      if (arg == NULL)
          return "LogLevel requires level keyword or module loglevel specifier";
  
      return update_loglevel(cmd, log, arg);
  }
  
  static const char *set_loglevel_override(cmd_parms *cmd, void *d_, int argc,
                                           char *const argv[])
  {
      core_server_config *sconf;
      conn_log_config *entry;
      int ret, i;
      const char *addr, *mask, *err;
  
      if (argc < 2)
          return "LogLevelOverride requires at least two arguments";
  
      entry = apr_pcalloc(cmd->pool, sizeof(conn_log_config));
      sconf = ap_get_core_module_config(cmd->server->module_config);
      if (!sconf->conn_log_level)
          sconf->conn_log_level = apr_array_make(cmd->pool, 4, sizeof(entry));
      APR_ARRAY_PUSH(sconf->conn_log_level, conn_log_config *) = entry;
  
      addr = argv[0];
      mask = ap_strchr_c(addr, '/');
      if (mask) {
          addr = apr_pstrmemdup(cmd->temp_pool, addr, mask - addr);
          mask++;
      }
      ret = apr_ipsubnet_create(&entry->subnet, addr, mask, cmd->pool);
      if (ret != APR_SUCCESS)
          return "parsing of subnet/netmask failed";
  
      for (i = 1; i < argc; i++) {
          if ((err = update_loglevel(cmd, &entry->log, argv[i])) != NULL)
              return err;
      }
      return NULL;
  }
  
  AP_DECLARE(const char *) ap_psignature(const char *prefix, request_rec *r)
  {
      char sport[20];
      core_dir_config *conf;
  
      conf = (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
      if ((conf->server_signature == srv_sig_off)
              || (conf->server_signature == srv_sig_unset)) {
          return "";
      }
  
      apr_snprintf(sport, sizeof sport, "%u", (unsigned) ap_get_server_port(r));
  
      if (conf->server_signature == srv_sig_withmail) {
          return apr_pstrcat(r->pool, prefix, "<address>",
                             ap_get_server_banner(),
                             " Server at <a href=\"",
                             ap_is_url(r->server->server_admin) ? "" : "mailto:",
                             ap_escape_html(r->pool, r->server->server_admin),
                             "\">",
                             ap_escape_html(r->pool, ap_get_server_name(r)),
                             "</a> Port ", sport,
                             "</address>\n", NULL);
      }
  
      return apr_pstrcat(r->pool, prefix, "<address>", ap_get_server_banner(),
                         " Server at ",
                         ap_escape_html(r->pool, ap_get_server_name(r)),
                         " Port ", sport,
                         "</address>\n", NULL);
  }
  
  /*
   * Handle a request to include the server's OS platform in the Server
   * response header field (the ServerTokens directive).  Unfortunately
   * this requires a new global in order to communicate the setting back to
   * http_main so it can insert the information in the right place in the
   * string.
   */
  
  static char *server_banner = NULL;
  static int banner_locked = 0;
  static const char *server_description = NULL;
  
  enum server_token_type {
      SrvTk_MAJOR,         /* eg: Apache/2 */
      SrvTk_MINOR,         /* eg. Apache/2.0 */
      SrvTk_MINIMAL,       /* eg: Apache/2.0.41 */
      SrvTk_OS,            /* eg: Apache/2.0.41 (UNIX) */
      SrvTk_FULL,          /* eg: Apache/2.0.41 (UNIX) PHP/4.2.2 FooBar/1.2b */
      SrvTk_PRODUCT_ONLY   /* eg: Apache */
  };
  static enum server_token_type ap_server_tokens = SrvTk_FULL;
  
  static apr_status_t reset_banner(void *dummy)
  {
      banner_locked = 0;
      ap_server_tokens = SrvTk_FULL;
      server_banner = NULL;
      server_description = NULL;
      return APR_SUCCESS;
  }
  
  AP_DECLARE(void) ap_get_server_revision(ap_version_t *version)
  {
      version->major = AP_SERVER_MAJORVERSION_NUMBER;
      version->minor = AP_SERVER_MINORVERSION_NUMBER;
      version->patch = AP_SERVER_PATCHLEVEL_NUMBER;
      version->add_string = AP_SERVER_ADD_STRING;
  }
  
  AP_DECLARE(const char *) ap_get_server_description(void)
  {
      return server_description ? server_description :
          AP_SERVER_BASEVERSION " (" PLATFORM ")";
  }
  
  AP_DECLARE(const char *) ap_get_server_banner(void)
  {
      return server_banner ? server_banner : AP_SERVER_BASEVERSION;
  }
  
  AP_DECLARE(void) ap_add_version_component(apr_pool_t *pconf, const char *component)
  {
      if (! banner_locked) {
          /*
           * If the version string is null, register our cleanup to reset the
           * pointer on pool destruction. We also know that, if NULL,
           * we are adding the original SERVER_BASEVERSION string.
           */
          if (server_banner == NULL) {
              apr_pool_cleanup_register(pconf, NULL, reset_banner,
                                        apr_pool_cleanup_null);
              server_banner = apr_pstrdup(pconf, component);
          }
          else {
              /*
               * Tack the given component identifier to the end of
               * the existing string.
               */
              server_banner = apr_pstrcat(pconf, server_banner, " ",
                                          component, NULL);
          }
      }
      server_description = apr_pstrcat(pconf, server_description, " ",
                                       component, NULL);
  }
  
  /*
   * This routine adds the real server base identity to the banner string,
   * and then locks out changes until the next reconfig.
   */
  static void set_banner(apr_pool_t *pconf)
  {
      if (ap_server_tokens == SrvTk_PRODUCT_ONLY) {
          ap_add_version_component(pconf, AP_SERVER_BASEPRODUCT);
      }
      else if (ap_server_tokens == SrvTk_MINIMAL) {
          ap_add_version_component(pconf, AP_SERVER_BASEVERSION);
      }
      else if (ap_server_tokens == SrvTk_MINOR) {
          ap_add_version_component(pconf, AP_SERVER_BASEPRODUCT "/" AP_SERVER_MINORREVISION);
      }
      else if (ap_server_tokens == SrvTk_MAJOR) {
          ap_add_version_component(pconf, AP_SERVER_BASEPRODUCT "/" AP_SERVER_MAJORVERSION);
      }
      else {
          ap_add_version_component(pconf, AP_SERVER_BASEVERSION " (" PLATFORM ")");
      }
  
      /*
       * Lock the server_banner string if we're not displaying
       * the full set of tokens
       */
      if (ap_server_tokens != SrvTk_FULL) {
          banner_locked++;
      }
      server_description = AP_SERVER_BASEVERSION " (" PLATFORM ")";
  }
  
  static const char *set_serv_tokens(cmd_parms *cmd, void *dummy,
                                     const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
  
      if (err != NULL) {
          return err;
      }
  
      if (!ap_cstr_casecmp(arg, "OS")) {
          ap_server_tokens = SrvTk_OS;
      }
      else if (!ap_cstr_casecmp(arg, "Min") || !ap_cstr_casecmp(arg, "Minimal")) {
          ap_server_tokens = SrvTk_MINIMAL;
      }
      else if (!ap_cstr_casecmp(arg, "Major")) {
          ap_server_tokens = SrvTk_MAJOR;
      }
      else if (!ap_cstr_casecmp(arg, "Minor") ) {
          ap_server_tokens = SrvTk_MINOR;
      }
      else if (!ap_cstr_casecmp(arg, "Prod") || !ap_cstr_casecmp(arg, "ProductOnly")) {
          ap_server_tokens = SrvTk_PRODUCT_ONLY;
      }
      else if (!ap_cstr_casecmp(arg, "Full")) {
          ap_server_tokens = SrvTk_FULL;
      }
      else {
          return "ServerTokens takes 1 argument: 'Prod(uctOnly)', 'Major', 'Minor', 'Min(imal)', 'OS', or 'Full'";
      }
  
      return NULL;
  }
  
  static const char *set_limit_req_line(cmd_parms *cmd, void *dummy,
                                        const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      int lim;
  
      if (err != NULL) {
          return err;
      }
  
      lim = atoi(arg);
      if (lim < 0) {
          return apr_pstrcat(cmd->temp_pool, "LimitRequestLine \"", arg,
                             "\" must be a non-negative integer", NULL);
      }
  
      cmd->server->limit_req_line = lim;
      return NULL;
  }
  
  static const char *set_limit_req_fieldsize(cmd_parms *cmd, void *dummy,
                                             const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      int lim;
  
      if (err != NULL) {
          return err;
      }
  
      lim = atoi(arg);
      if (lim < 0) {
          return apr_pstrcat(cmd->temp_pool, "LimitRequestFieldsize \"", arg,
                            "\" must be a non-negative integer",
                            NULL);
      }
  
      cmd->server->limit_req_fieldsize = lim;
      return NULL;
  }
  
  static const char *set_limit_req_fields(cmd_parms *cmd, void *dummy,
                                          const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      int lim;
  
      if (err != NULL) {
          return err;
      }
  
      lim = atoi(arg);
      if (lim < 0) {
          return apr_pstrcat(cmd->temp_pool, "LimitRequestFields \"", arg,
                             "\" must be a non-negative integer (0 = no limit)",
                             NULL);
      }
  
      cmd->server->limit_req_fields = lim;
      return NULL;
  }
  
  static const char *set_limit_req_body(cmd_parms *cmd, void *conf_,
                                        const char *arg)
  {
      core_dir_config *conf = conf_;
      char *errp;
  
      if (APR_SUCCESS != apr_strtoff(&conf->limit_req_body, arg, &errp, 10)) {
          return "LimitRequestBody argument is not parsable.";
      }
      if (*errp || conf->limit_req_body < 0) {
          return "LimitRequestBody requires a non-negative integer.";
      }
  
      return NULL;
  }
  
  static const char *set_limit_xml_req_body(cmd_parms *cmd, void *conf_,
                                            const char *arg)
  {
      core_dir_config *conf = conf_;
  
      conf->limit_xml_body = atol(arg);
      if (conf->limit_xml_body < 0)
          return "LimitXMLRequestBody requires a non-negative integer.";
  
      return NULL;
  }
  
  static const char *set_max_ranges(cmd_parms *cmd, void *conf_, const char *arg)
  {
      core_dir_config *conf = conf_;
      int val = 0;
  
      if (!ap_cstr_casecmp(arg, "none")) {
          val = AP_MAXRANGES_NORANGES;
      }
      else if (!ap_cstr_casecmp(arg, "default")) {
          val = AP_MAXRANGES_DEFAULT;
      }
      else if (!ap_cstr_casecmp(arg, "unlimited")) {
          val = AP_MAXRANGES_UNLIMITED;
      }
      else {
          val = atoi(arg);
          if (val <= 0)
              return "MaxRanges requires 'none', 'default', 'unlimited' or "
                     "a positive integer";
      }
  
      conf->max_ranges = val;
  
      return NULL;
  }
  
  static const char *set_max_overlaps(cmd_parms *cmd, void *conf_, const char *arg)
  {
      core_dir_config *conf = conf_;
      int val = 0;
  
      if (!ap_cstr_casecmp(arg, "none")) {
          val = AP_MAXRANGES_NORANGES;
      }
      else if (!ap_cstr_casecmp(arg, "default")) {
          val = AP_MAXRANGES_DEFAULT;
      }
      else if (!ap_cstr_casecmp(arg, "unlimited")) {
          val = AP_MAXRANGES_UNLIMITED;
      }
      else {
          val = atoi(arg);
          if (val <= 0)
              return "MaxRangeOverlaps requires 'none', 'default', 'unlimited' or "
              "a positive integer";
      }
  
      conf->max_overlaps = val;
  
      return NULL;
  }
  
  static const char *set_max_reversals(cmd_parms *cmd, void *conf_, const char *arg)
  {
      core_dir_config *conf = conf_;
      int val = 0;
  
      if (!ap_cstr_casecmp(arg, "none")) {
          val = AP_MAXRANGES_NORANGES;
      }
      else if (!ap_cstr_casecmp(arg, "default")) {
          val = AP_MAXRANGES_DEFAULT;
      }
      else if (!ap_cstr_casecmp(arg, "unlimited")) {
          val = AP_MAXRANGES_UNLIMITED;
      }
      else {
          val = atoi(arg);
          if (val <= 0)
              return "MaxRangeReversals requires 'none', 'default', 'unlimited' or "
              "a positive integer";
      }
  
      conf->max_reversals = val;
  
      return NULL;
  }
  
  AP_DECLARE(apr_size_t) ap_get_limit_xml_body(const request_rec *r)
  {
      core_dir_config *conf;
  
      conf = ap_get_core_module_config(r->per_dir_config);
      if (conf->limit_xml_body == AP_LIMIT_UNSET)
          return AP_DEFAULT_LIMIT_XML_BODY;
  
      return (apr_size_t)conf->limit_xml_body;
  }
  
  #if !defined (RLIMIT_CPU) || !(defined (RLIMIT_DATA) || defined (RLIMIT_VMEM) || defined(RLIMIT_AS)) || !defined (RLIMIT_NPROC)
  static const char *no_set_limit(cmd_parms *cmd, void *conf_,
                                  const char *arg, const char *arg2)
  {
      ap_log_error(APLOG_MARK, APLOG_ERR, 0, cmd->server, APLOGNO(00118)
                  "%s not supported on this platform", cmd->cmd->name);
  
      return NULL;
  }
  #endif
  
  #ifdef RLIMIT_CPU
  static const char *set_limit_cpu(cmd_parms *cmd, void *conf_,
                                   const char *arg, const char *arg2)
  {
      core_dir_config *conf = conf_;
  
      ap_unixd_set_rlimit(cmd, &conf->limit_cpu, arg, arg2, RLIMIT_CPU);
      return NULL;
  }
  #endif
  
  #if defined (RLIMIT_DATA) || defined (RLIMIT_VMEM) || defined(RLIMIT_AS)
  static const char *set_limit_mem(cmd_parms *cmd, void *conf_,
                                   const char *arg, const char * arg2)
  {
      core_dir_config *conf = conf_;
  
  #if defined(RLIMIT_AS)
      ap_unixd_set_rlimit(cmd, &conf->limit_mem, arg, arg2 ,RLIMIT_AS);
  #elif defined(RLIMIT_DATA)
      ap_unixd_set_rlimit(cmd, &conf->limit_mem, arg, arg2, RLIMIT_DATA);
  #elif defined(RLIMIT_VMEM)
      ap_unixd_set_rlimit(cmd, &conf->limit_mem, arg, arg2, RLIMIT_VMEM);
  #endif
  
      return NULL;
  }
  #endif
  
  #ifdef RLIMIT_NPROC
  static const char *set_limit_nproc(cmd_parms *cmd, void *conf_,
                                     const char *arg, const char * arg2)
  {
      core_dir_config *conf = conf_;
  
      ap_unixd_set_rlimit(cmd, &conf->limit_nproc, arg, arg2, RLIMIT_NPROC);
      return NULL;
  }
  #endif
  
  static const char *set_recursion_limit(cmd_parms *cmd, void *dummy,
                                         const char *arg1, const char *arg2)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
      int limit = atoi(arg1);
  
      if (limit <= 0) {
          return "The recursion limit must be greater than zero.";
      }
      if (limit < 4) {
          ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00119)
                       "Limiting internal redirects to very low numbers may "
                       "cause normal requests to fail.");
      }
  
      conf->redirect_limit = limit;
  
      if (arg2) {
          limit = atoi(arg2);
  
          if (limit <= 0) {
              return "The recursion limit must be greater than zero.";
          }
          if (limit < 4) {
              ap_log_error(APLOG_MARK, APLOG_WARNING, 0, cmd->server, APLOGNO(00120)
                           "Limiting the subrequest depth to a very low level may"
                           " cause normal requests to fail.");
          }
      }
  
      conf->subreq_limit = limit;
  
      return NULL;
  }
  
  static void log_backtrace(const request_rec *r)
  {
      const request_rec *top = r;
  
      ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00121)
                    "r->uri = %s", r->uri ? r->uri : "(unexpectedly NULL)");
  
      while (top && (top->prev || top->main)) {
          if (top->prev) {
              top = top->prev;
              ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00122)
                            "redirected from r->uri = %s",
                            top->uri ? top->uri : "(unexpectedly NULL)");
          }
  
          if (!top->prev && top->main) {
              top = top->main;
              ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(00123)
                            "subrequested from r->uri = %s",
                            top->uri ? top->uri : "(unexpectedly NULL)");
          }
      }
  }
  
  /*
   * check whether redirect limit is reached
   */
  AP_DECLARE(int) ap_is_recursion_limit_exceeded(const request_rec *r)
  {
      core_server_config *conf =
          ap_get_core_module_config(r->server->module_config);
      const request_rec *top = r;
      int redirects = 0, subreqs = 0;
      int rlimit = conf->redirect_limit
                   ? conf->redirect_limit
                   : AP_DEFAULT_MAX_INTERNAL_REDIRECTS;
      int slimit = conf->subreq_limit
                   ? conf->subreq_limit
                   : AP_DEFAULT_MAX_SUBREQ_DEPTH;
  
  
      while (top->prev || top->main) {
          if (top->prev) {
              if (++redirects >= rlimit) {
                  /* uuh, too much. */
                  ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00124)
                                "Request exceeded the limit of %d internal "
                                "redirects due to probable configuration error. "
                                "Use 'LimitInternalRecursion' to increase the "
                                "limit if necessary. Use 'LogLevel debug' to get "
                                "a backtrace.", rlimit);
  
                  /* post backtrace */
                  log_backtrace(r);
  
                  /* return failure */
                  return 1;
              }
  
              top = top->prev;
          }
  
          if (!top->prev && top->main) {
              if (++subreqs >= slimit) {
                  /* uuh, too much. */
                  ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00125)
                                "Request exceeded the limit of %d subrequest "
                                "nesting levels due to probable configuration "
                                "error. Use 'LimitInternalRecursion' to increase "
                                "the limit if necessary. Use 'LogLevel debug' to "
                                "get a backtrace.", slimit);
  
                  /* post backtrace */
                  log_backtrace(r);
  
                  /* return failure */
                  return 1;
              }
  
              top = top->main;
          }
      }
  
      /* recursion state: ok */
      return 0;
  }
  
  static const char *set_trace_enable(cmd_parms *cmd, void *dummy,
                                      const char *arg1)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
  
      if (ap_cstr_casecmp(arg1, "on") == 0) {
          conf->trace_enable = AP_TRACE_ENABLE;
      }
      else if (ap_cstr_casecmp(arg1, "off") == 0) {
          conf->trace_enable = AP_TRACE_DISABLE;
      }
      else if (ap_cstr_casecmp(arg1, "extended") == 0) {
          conf->trace_enable = AP_TRACE_EXTENDED;
      }
      else {
          return "TraceEnable must be one of 'on', 'off', or 'extended'";
      }
  
      return NULL;
  }
  
  static const char *set_protocols(cmd_parms *cmd, void *dummy,
                                   const char *arg)
  {
      core_server_config *conf =
      ap_get_core_module_config(cmd->server->module_config);
      const char **np;
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
  
      if (err) {
          return err;
      }
      
      np = (const char **)apr_array_push(conf->protocols);
      *np = arg;
  
      return NULL;
  }
  
  static const char *set_protocols_honor_order(cmd_parms *cmd, void *dummy,
                                               const char *arg)
  {
      core_server_config *conf =
      ap_get_core_module_config(cmd->server->module_config);
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
      
      if (err) {
          return err;
      }
      
      if (ap_cstr_casecmp(arg, "on") == 0) {
          conf->protocols_honor_order = 1;
      }
      else if (ap_cstr_casecmp(arg, "off") == 0) {
          conf->protocols_honor_order = 0;
      }
      else {
          return "ProtocolsHonorOrder must be 'on' or 'off'";
      }
      
      return NULL;
  }
  
  static const char *set_http_protocol_options(cmd_parms *cmd, void *dummy,
                                               const char *arg)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
  
      if (strcasecmp(arg, "allow0.9") == 0)
          conf->http09_enable |= AP_HTTP09_ENABLE;
      else if (strcasecmp(arg, "require1.0") == 0)
          conf->http09_enable |= AP_HTTP09_DISABLE;
      else if (strcasecmp(arg, "strict") == 0)
          conf->http_conformance |= AP_HTTP_CONFORMANCE_STRICT;
      else if (strcasecmp(arg, "unsafe") == 0)
          conf->http_conformance |= AP_HTTP_CONFORMANCE_UNSAFE;
      else if (strcasecmp(arg, "registeredmethods") == 0)
          conf->http_methods |= AP_HTTP_METHODS_REGISTERED;
      else if (strcasecmp(arg, "lenientmethods") == 0)
          conf->http_methods |= AP_HTTP_METHODS_LENIENT;
      else
          return "HttpProtocolOptions accepts "
                 "'Unsafe' or 'Strict' (default), "
                 "'RegisteredMethods' or 'LenientMethods' (default), and "
                 "'Require1.0' or 'Allow0.9' (default)";
  
      if ((conf->http09_enable & AP_HTTP09_ENABLE)
              && (conf->http09_enable & AP_HTTP09_DISABLE))
          return "HttpProtocolOptions 'Allow0.9' and 'Require1.0'"
                 " are mutually exclusive";
  
      if ((conf->http_conformance & AP_HTTP_CONFORMANCE_STRICT)
              && (conf->http_conformance & AP_HTTP_CONFORMANCE_UNSAFE))
          return "HttpProtocolOptions 'Strict' and 'Unsafe'"
                 " are mutually exclusive";
  
      if ((conf->http_methods & AP_HTTP_METHODS_REGISTERED)
              && (conf->http_methods & AP_HTTP_METHODS_LENIENT))
          return "HttpProtocolOptions 'RegisteredMethods' and 'LenientMethods'"
                 " are mutually exclusive";
  
      return NULL;
  }
  
  static const char *set_async_filter(cmd_parms *cmd, void *dummy,
                                               const char *arg)
  {
      core_server_config *conf =
      ap_get_core_module_config(cmd->server->module_config);
      const char *err = ap_check_cmd_context(cmd, NOT_IN_DIR_CONTEXT);
  
      if (err) {
          return err;
      }
  
      if (ap_cstr_casecmp(arg, "network") == 0) {
          conf->async_filter = AP_FTYPE_NETWORK;
      }
      else if (ap_cstr_casecmp(arg, "connection") == 0) {
          conf->async_filter = AP_FTYPE_CONNECTION;
      }
      else if (ap_cstr_casecmp(arg, "request") == 0) {
          conf->async_filter = 0;
      }
      else {
          return "AsyncFilter must be 'network', 'connection' or 'request'";
      }
      conf->async_filter_set = 1;
  
      return NULL;
  }
  
  static const char *set_http_method(cmd_parms *cmd, void *conf, const char *arg)
  {
      const char *err = ap_check_cmd_context(cmd, GLOBAL_ONLY);
      if (err != NULL)
          return err;
      ap_method_register(cmd->pool, arg);
      return NULL;
  }
  
  static const char *set_cl_head_zero(cmd_parms *cmd, void *dummy, int arg)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
  
      if (arg) {
          conf->http_cl_head_zero = AP_HTTP_CL_HEAD_ZERO_ENABLE;
      } else {
          conf->http_cl_head_zero = AP_HTTP_CL_HEAD_ZERO_DISABLE;
      }
      return NULL;
  }
  
  static const char *set_expect_strict(cmd_parms *cmd, void *dummy, int arg)
  {
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
  
      if (arg) {
          conf->http_expect_strict = AP_HTTP_EXPECT_STRICT_ENABLE;
      } else {
          conf->http_expect_strict = AP_HTTP_EXPECT_STRICT_DISABLE;
      }
      return NULL;
  }
  
  static apr_hash_t *errorlog_hash;
  
  static int log_constant_item(const ap_errorlog_info *info, const char *arg,
                               char *buf, int buflen)
  {
      char *end = apr_cpystrn(buf, arg, buflen);
      return end - buf;
  }
  
  static char *parse_errorlog_misc_string(apr_pool_t *p,
                                          ap_errorlog_format_item *it,
                                          const char **sa)
  {
      const char *s;
      char scratch[MAX_STRING_LEN];
      char *d = scratch;
      /*
       * non-leading white space terminates this string to allow the next field
       * separator to be inserted
       */
      int at_start = 1;
  
      it->func = log_constant_item;
      s = *sa;
  
      while (*s && *s != '%' && (*s != ' ' || at_start) && d < scratch + MAX_STRING_LEN) {
          if (*s != '\\') {
              if (*s != ' ') {
                  at_start = 0;
              }
              *d++ = *s++;
          }
          else {
              s++;
              switch (*s) {
              case 'r':
                  *d++ = '\r';
                  s++;
                  break;
              case 'n':
                  *d++ = '\n';
                  s++;
                  break;
              case 't':
                  *d++ = '\t';
                  s++;
                  break;
              case '\0':
                  /* handle end of string */
                  *d++ = '\\';
                  break;
              default:
                  /* copy next char verbatim */
                  *d++ = *s++;
                  break;
              }
          }
      }
      *d = '\0';
      it->arg = apr_pstrdup(p, scratch);
  
      *sa = s;
      return NULL;
  }
  
  static char *parse_errorlog_item(apr_pool_t *p, ap_errorlog_format_item *it,
                                   const char **sa)
  {
      const char *s = *sa;
      ap_errorlog_handler *handler;
      int i;
  
      if (*s != '%') {
          if (*s == ' ') {
              it->flags |= AP_ERRORLOG_FLAG_FIELD_SEP;
          }
          return parse_errorlog_misc_string(p, it, sa);
      }
  
      ++s;
  
      if (*s == ' ') {
          /* percent-space (% ) is a field separator */
          it->flags |= AP_ERRORLOG_FLAG_FIELD_SEP;
          *sa = ++s;
          /* recurse */
          return parse_errorlog_item(p, it, sa);
      }
      else if (*s == '%') {
          it->arg = "%";
          it->func = log_constant_item;
          *sa = ++s;
          return NULL;
      }
  
      while (*s) {
          switch (*s) {
          case '{':
              ++s;
              it->arg = ap_getword(p, &s, '}');
              break;
          case '+':
              ++s;
              it->flags |= AP_ERRORLOG_FLAG_REQUIRED;
              break;
          case '-':
              ++s;
              it->flags |= AP_ERRORLOG_FLAG_NULL_AS_HYPHEN;
              break;
          case '0':
          case '1':
          case '2':
          case '3':
          case '4':
          case '5':
          case '6':
          case '7':
          case '8':
          case '9':
              i = *s - '0';
              while (apr_isdigit(*++s))
                  i = i * 10 + (*s) - '0';
              it->min_loglevel = i;
              break;
          case 'M':
              it->func = NULL;
              it->flags |= AP_ERRORLOG_FLAG_MESSAGE;
              *sa = ++s;
              return NULL;
          default:
              handler = (ap_errorlog_handler *)apr_hash_get(errorlog_hash, s, 1);
              if (!handler) {
                  char dummy[2];
  
                  dummy[0] = *s;
                  dummy[1] = '\0';
                  return apr_pstrcat(p, "Unrecognized error log format directive %",
                                 dummy, NULL);
              }
              it->func = handler->func;
              *sa = ++s;
              return NULL;
          }
      }
  
      return "Ran off end of error log format parsing args to some directive";
  }
  
  static apr_array_header_t *parse_errorlog_string(apr_pool_t *p,
                                                   const char *s,
                                                   const char **err,
                                                   int is_main_fmt)
  {
      apr_array_header_t *a = apr_array_make(p, 30,
                                             sizeof(ap_errorlog_format_item));
      char *res;
      int seen_msg_fmt = 0;
  
      while (s && *s) {
          ap_errorlog_format_item *item =
              (ap_errorlog_format_item *)apr_array_push(a);
          memset(item, 0, sizeof(*item));
          res = parse_errorlog_item(p, item, &s);
          if (res) {
              *err = res;
              return NULL;
          }
          if (item->flags & AP_ERRORLOG_FLAG_MESSAGE) {
              if (!is_main_fmt) {
                  *err = "%M cannot be used in once-per-request or "
                         "once-per-connection formats";
                  return NULL;
              }
              seen_msg_fmt = 1;
          }
          if (is_main_fmt && item->flags & AP_ERRORLOG_FLAG_REQUIRED) {
              *err = "The '+' flag cannot be used in the main error log format";
              return NULL;
          }
          if (!is_main_fmt && item->min_loglevel) {
              *err = "The loglevel cannot be used as a condition in "
                     "once-per-request or once-per-connection formats";
              return NULL;
          }
          if (item->min_loglevel > APLOG_TRACE8) {
              *err = "The specified loglevel modifier is out of range";
              return NULL;
          }
      }
  
      if (is_main_fmt && !seen_msg_fmt) {
          *err = "main ErrorLogFormat must contain message format string '%M'";
          return NULL;
      }
  
      return a;
  }
  
  static const char *set_errorlog(cmd_parms *cmd, void *dummy, const char *arg1,
                                  const char *arg2)
  {
      ap_errorlog_provider *provider;
      const char *err;
      cmd->server->errorlog_provider = NULL;
  
      if (!arg2) {
          /* Stay backward compatible and check for "syslog" */
          if (strncmp("syslog", arg1, 6) == 0) {
              arg2 = arg1 + 7; /* skip the ':' if any */
              arg1 = "syslog";
          }
          else {
              /* Admin can define only "ErrorLog provider" and we should 
               * still handle that using the defined provider, but with empty
               * error_fname. */
              provider = ap_lookup_provider(AP_ERRORLOG_PROVIDER_GROUP, arg1,
                                            AP_ERRORLOG_PROVIDER_VERSION);
              if (provider) {
                  arg2 = "";
              }
              else {
                  return set_server_string_slot(cmd, dummy, arg1);
              }
          }
      }
  
      if (strcmp("file", arg1) == 0) {
          return set_server_string_slot(cmd, dummy, arg2);
      }
  
      provider = ap_lookup_provider(AP_ERRORLOG_PROVIDER_GROUP, arg1,
                                      AP_ERRORLOG_PROVIDER_VERSION);
      if (!provider) {
          return apr_psprintf(cmd->pool,
                              "Unknown ErrorLog provider: %s",
                              arg1);
      }
  
      err = provider->parse_errorlog_arg(cmd, arg2);
      if (err) {
          return err;
      }
  
      cmd->server->errorlog_provider = provider;
      return set_server_string_slot(cmd, dummy, arg2);
  }
  
  static const char *set_errorlog_format(cmd_parms *cmd, void *dummy,
                                         const char *arg1, const char *arg2)
  {
      const char *err_string = NULL;
      core_server_config *conf =
          ap_get_core_module_config(cmd->server->module_config);
  
      if (!arg2) {
          conf->error_log_format = parse_errorlog_string(cmd->pool, arg1,
                                                         &err_string, 1);
      }
      else if (!ap_cstr_casecmp(arg1, "connection")) {
          if (!conf->error_log_conn) {
              conf->error_log_conn = apr_array_make(cmd->pool, 5,
                                                    sizeof(apr_array_header_t *));
          }
  
          if (*arg2) {
              apr_array_header_t **e;
              e = (apr_array_header_t **) apr_array_push(conf->error_log_conn);
              *e = parse_errorlog_string(cmd->pool, arg2, &err_string, 0);
          }
      }
      else if (!ap_cstr_casecmp(arg1, "request")) {
          if (!conf->error_log_req) {
              conf->error_log_req = apr_array_make(cmd->pool, 5,
                                                   sizeof(apr_array_header_t *));
          }
  
          if (*arg2) {
              apr_array_header_t **e;
              e = (apr_array_header_t **) apr_array_push(conf->error_log_req);
              *e = parse_errorlog_string(cmd->pool, arg2, &err_string, 0);
          }
      }
      else {
          err_string = "ErrorLogFormat type must be one of request, connection";
      }
  
      return err_string;
  }
  
  AP_DECLARE(void) ap_register_errorlog_handler(apr_pool_t *p, char *tag,
                                                ap_errorlog_handler_fn_t *handler,
                                                int flags)
  {
      ap_errorlog_handler *log_struct = apr_palloc(p, sizeof(*log_struct));
      log_struct->func = handler;
      log_struct->flags = flags;
  
      apr_hash_set(errorlog_hash, tag, 1, (const void *)log_struct);
  }
  
  
  static const char *set_merge_trailers(cmd_parms *cmd, void *dummy, int arg)
  {
      core_server_config *conf = ap_get_module_config(cmd->server->module_config,
                                                      &core_module);
      conf->merge_trailers = (arg ? AP_MERGE_TRAILERS_ENABLE :
              AP_MERGE_TRAILERS_DISABLE);
  
      return NULL;
  }
  
  /* Note --- ErrorDocument will now work from .htaccess files.
   * The AllowOverride of Fileinfo allows webmasters to turn it off
   */
  
  static const command_rec core_cmds[] = {
  
  /* Old access config file commands */
  
  AP_INIT_RAW_ARGS("<Directory", dirsection, NULL, RSRC_CONF,
    "Container for directives affecting resources located in the specified "
    "directories"),
  AP_INIT_RAW_ARGS("<Location", urlsection, NULL, RSRC_CONF,
    "Container for directives affecting resources accessed through the "
    "specified URL paths"),
  AP_INIT_RAW_ARGS("<VirtualHost", virtualhost_section, NULL, RSRC_CONF,
    "Container to map directives to a particular virtual host, takes one or "
    "more host addresses"),
  AP_INIT_RAW_ARGS("<Files", filesection, NULL, OR_ALL,
    "Container for directives affecting files matching specified patterns"),
  AP_INIT_RAW_ARGS("<Limit", ap_limit_section, NULL, OR_LIMIT | OR_AUTHCFG,
    "Container for authentication directives when accessed using specified HTTP "
    "methods"),
  AP_INIT_RAW_ARGS("<LimitExcept", ap_limit_section, (void*)1,
                   OR_LIMIT | OR_AUTHCFG,
    "Container for authentication directives to be applied when any HTTP "
    "method other than those specified is used to access the resource"),
  AP_INIT_RAW_ARGS("<IfModule", start_cond_section, (void *)test_ifmod_section,
                EXEC_ON_READ | OR_ALL,
    "Container for directives based on existence of specified modules"),
  AP_INIT_RAW_ARGS("<IfDefine", start_cond_section, (void *)test_ifdefine_section,
                EXEC_ON_READ | OR_ALL,
    "Container for directives based on existence of command line defines"),
  AP_INIT_RAW_ARGS("<IfFile", start_cond_section, (void *)test_iffile_section,
                EXEC_ON_READ | OR_ALL,
    "Container for directives based on existence of files on disk"),
  AP_INIT_RAW_ARGS("<IfDirective", start_cond_section, (void *)test_ifdirective_section,
                EXEC_ON_READ | OR_ALL,
    "Container for directives based on existence of named directive"),
  AP_INIT_RAW_ARGS("<IfSection", start_cond_section, (void *)test_ifsection_section,
                EXEC_ON_READ | OR_ALL,
    "Container for directives based on existence of named section"),
  AP_INIT_RAW_ARGS("<DirectoryMatch", dirsection, (void*)1, RSRC_CONF,
    "Container for directives affecting resources located in the "
    "specified directories"),
  AP_INIT_RAW_ARGS("<LocationMatch", urlsection, (void*)1, RSRC_CONF,
    "Container for directives affecting resources accessed through the "
    "specified URL paths"),
  AP_INIT_RAW_ARGS("<FilesMatch", filesection, (void*)1, OR_ALL,
    "Container for directives affecting files matching specified patterns"),
  #ifdef GPROF
  AP_INIT_TAKE1("GprofDir", set_gprof_dir, NULL, RSRC_CONF,
    "Directory to plop gmon.out files"),
  #endif
  AP_INIT_TAKE1("AddDefaultCharset", set_add_default_charset, NULL, OR_FILEINFO,
    "The name of the default charset to add to any Content-Type without one or 'Off' to disable"),
  AP_INIT_TAKE1("AcceptPathInfo", set_accept_path_info, NULL, OR_FILEINFO,
    "Set to on or off for PATH_INFO to be accepted by handlers, or default for the per-handler preference"),
  AP_INIT_TAKE12("Define", set_define, NULL, EXEC_ON_READ|RSRC_CONF,
                "Define a variable, optionally to a value.  Same as passing -D to the command line."),
  AP_INIT_TAKE1("UnDefine", unset_define, NULL, EXEC_ON_READ|RSRC_CONF,
                "Undefine the existence of a variable. Undo a Define."),
  AP_INIT_RAW_ARGS("Error", generate_message, (void*) APLOG_ERR, OR_ALL,
                   "Generate error message from within configuration."),
  AP_INIT_RAW_ARGS("Warning", generate_message, (void*) APLOG_WARNING, OR_ALL,
                   "Generate warning message from within configuration."),
  AP_INIT_RAW_ARGS("<If", ifsection, COND_IF, OR_ALL,
    "Container for directives to be conditionally applied"),
  AP_INIT_RAW_ARGS("<ElseIf", ifsection, COND_ELSEIF, OR_ALL,
    "Container for directives to be conditionally applied"),
  AP_INIT_RAW_ARGS("<Else", ifsection, COND_ELSE, OR_ALL,
    "Container for directives to be conditionally applied"),
  
  /* Old resource config file commands */
  
  AP_INIT_RAW_ARGS("AccessFileName", set_access_name, NULL, RSRC_CONF,
    "Name(s) of per-directory config files (default: .htaccess)"),
  AP_INIT_TAKE1("DocumentRoot", set_document_root, NULL, RSRC_CONF,
    "Root directory of the document tree"),
  AP_INIT_TAKE2("ErrorDocument", set_error_document, NULL, OR_FILEINFO,
    "Change responses for HTTP errors"),
  AP_INIT_RAW_ARGS("AllowOverride", set_override, NULL, ACCESS_CONF,
    "Controls what groups of directives can be configured by per-directory "
    "config files"),
  AP_INIT_TAKE_ARGV("AllowOverrideList", set_override_list, NULL, ACCESS_CONF,
    "Controls what individual directives can be configured by per-directory "
    "config files"),
  AP_INIT_RAW_ARGS("Options", set_options, NULL, OR_OPTIONS,
    "Set a number of attributes for a given directory"),
  AP_INIT_TAKE1("DefaultType", set_default_type, NULL, OR_FILEINFO,
    "the default media type for otherwise untyped files (DEPRECATED)"),
  AP_INIT_RAW_ARGS("FileETag", set_etag_bits, NULL, OR_FILEINFO,
    "Specify components used to construct a file's ETag"),
  AP_INIT_TAKE1("EnableMMAP", set_enable_mmap, NULL, OR_FILEINFO,
    "Controls whether memory-mapping may be used to read files"),
  AP_INIT_TAKE1("EnableSendfile", set_enable_sendfile, NULL, OR_FILEINFO,
    "Controls whether sendfile may be used to transmit files"),
  AP_INIT_TAKE1("ReadBufferSize", set_read_buf_size, NULL, ACCESS_CONF|RSRC_CONF,
    "Size (in bytes) of the memory buffers used to read data"),
  AP_INIT_TAKE1("FlushMaxThreshold", set_flush_max_threshold, NULL, RSRC_CONF,
    "Maximum threshold above which pending data are flushed to the network"),
  AP_INIT_TAKE1("FlushMaxPipelined", set_flush_max_pipelined, NULL, RSRC_CONF,
    "Maximum number of pipelined responses (pending) above which they are "
    "flushed to the network"),
  
  /* Old server config file commands */
  
  AP_INIT_TAKE1("Protocol", set_protocol, NULL, RSRC_CONF,
    "Set the Protocol for httpd to use."),
  AP_INIT_TAKE2("AcceptFilter", set_accf_map, NULL, RSRC_CONF,
    "Set the Accept Filter to use for a protocol"),
  AP_INIT_TAKE1("Port", ap_set_deprecated, NULL, RSRC_CONF,
    "Port was replaced with Listen in Apache 2.0"),
  AP_INIT_TAKE1("HostnameLookups", set_hostname_lookups, NULL,
    ACCESS_CONF|RSRC_CONF,
    "\"on\" to enable, \"off\" to disable reverse DNS lookups, or \"double\" to "
    "enable double-reverse DNS lookups"),
  AP_INIT_TAKE1("ServerAdmin", set_server_string_slot,
    (void *)APR_OFFSETOF(server_rec, server_admin), RSRC_CONF,
    "The email address of the server administrator"),
  AP_INIT_TAKE1("ServerName", server_hostname_port, NULL, RSRC_CONF,
    "The hostname and port of the server"),
  AP_INIT_TAKE1("ServerSignature", set_signature_flag, NULL, OR_ALL,
    "En-/disable server signature (on|off|email)"),
  AP_INIT_TAKE1("ServerRoot", set_server_root, NULL, RSRC_CONF | EXEC_ON_READ,
    "Common directory of server-related files (logs, confs, etc.)"),
  AP_INIT_TAKE1("DefaultRuntimeDir", set_runtime_dir, NULL, RSRC_CONF | EXEC_ON_READ,
    "Common directory for run-time files (shared memory, locks, etc.)"),
  AP_INIT_TAKE1("DefaultStateDir", set_state_dir, NULL, RSRC_CONF | EXEC_ON_READ,
    "Common directory for persistent state (databases, long-lived caches, etc.)"),
  AP_INIT_TAKE12("ErrorLog", set_errorlog,
    (void *)APR_OFFSETOF(server_rec, error_fname), RSRC_CONF,
    "The filename of the error log"),
  AP_INIT_TAKE12("ErrorLogFormat", set_errorlog_format, NULL, RSRC_CONF,
    "Format string for the ErrorLog"),
  AP_INIT_RAW_ARGS("ServerAlias", set_server_alias, NULL, RSRC_CONF,
    "A name or names alternately used to access the server"),
  AP_INIT_TAKE1("ServerPath", set_serverpath, NULL, RSRC_CONF,
    "The pathname the server can be reached at"),
  AP_INIT_TAKE1("Timeout", set_timeout, NULL, RSRC_CONF,
    "Timeout duration (sec)"),
  AP_INIT_TAKE1("UseCanonicalName", set_use_canonical_name, NULL,
    RSRC_CONF|ACCESS_CONF,
    "How to work out the ServerName : Port when constructing URLs"),
  AP_INIT_TAKE1("UseCanonicalPhysicalPort", set_use_canonical_phys_port, NULL,
    RSRC_CONF|ACCESS_CONF,
    "Whether to use the physical Port when constructing URLs"),
  /* TODO: RlimitFoo should all be part of mod_cgi, not in the core */
  /* TODO: ListenBacklog in MPM */
  AP_INIT_TAKE1("Include", include_config, NULL,
    (RSRC_CONF | ACCESS_CONF | EXEC_ON_READ),
    "Name(s) of the config file(s) to be included; fails if the wildcard does "
    "not match at least one file"),
  AP_INIT_TAKE1("IncludeOptional", include_config, (void*)1,
    (RSRC_CONF | ACCESS_CONF | EXEC_ON_READ),
    "Name or pattern of the config file(s) to be included; ignored if the file "
    "does not exist or the pattern does not match any files"),
  AP_INIT_ITERATE("LogLevel", set_loglevel, NULL, RSRC_CONF|ACCESS_CONF,
    "Level of verbosity in error logging"),
  AP_INIT_TAKE_ARGV("LogLevelOverride", set_loglevel_override, NULL, RSRC_CONF,
    "Override LogLevel for clients with certain IPs"),
  AP_INIT_TAKE1("NameVirtualHost", ap_set_name_virtual_host, NULL, RSRC_CONF,
    "A numeric IP address:port, or the name of a host"),
  AP_INIT_TAKE1("ServerTokens", set_serv_tokens, NULL, RSRC_CONF,
    "Determine tokens displayed in the Server: header - Min(imal), "
    "Major, Minor, Prod(uctOnly), OS, or Full"),
  AP_INIT_TAKE1("LimitRequestLine", set_limit_req_line, NULL, RSRC_CONF,
    "Limit on maximum size of an HTTP request line"),
  AP_INIT_TAKE1("LimitRequestFieldsize", set_limit_req_fieldsize, NULL,
    RSRC_CONF,
    "Limit on maximum size of an HTTP request header field"),
  AP_INIT_TAKE1("LimitRequestFields", set_limit_req_fields, NULL, RSRC_CONF,
    "Limit (0 = unlimited) on max number of header fields in a request message"),
  AP_INIT_TAKE1("LimitRequestBody", set_limit_req_body,
    (void*)APR_OFFSETOF(core_dir_config, limit_req_body), OR_ALL,
    "Limit (in bytes) on maximum size of request message body"),
  AP_INIT_TAKE1("LimitXMLRequestBody", set_limit_xml_req_body, NULL, OR_ALL,
                "Limit (in bytes) on maximum size of an XML-based request "
                "body"),
  AP_INIT_RAW_ARGS("Mutex", ap_set_mutex, NULL, RSRC_CONF,
                   "mutex (or \"default\") and mechanism"),
  
  AP_INIT_TAKE1("MaxRanges", set_max_ranges, NULL, RSRC_CONF|ACCESS_CONF,
                "Maximum number of Ranges in a request before returning the entire "
                "resource, or 0 for unlimited"),
  AP_INIT_TAKE1("MaxRangeOverlaps", set_max_overlaps, NULL, RSRC_CONF|ACCESS_CONF,
                "Maximum number of overlaps in Ranges in a request before returning the entire "
                "resource, or 0 for unlimited"),
  AP_INIT_TAKE1("MaxRangeReversals", set_max_reversals, NULL, RSRC_CONF|ACCESS_CONF,
                "Maximum number of reversals in Ranges in a request before returning the entire "
                "resource, or 0 for unlimited"),
  /* System Resource Controls */
  #ifdef RLIMIT_CPU
  AP_INIT_TAKE12("RLimitCPU", set_limit_cpu,
    (void*)APR_OFFSETOF(core_dir_config, limit_cpu),
    OR_ALL, "Soft/hard limits for max CPU usage in seconds"),
  #else
  AP_INIT_TAKE12("RLimitCPU", no_set_limit, NULL,
    OR_ALL, "Soft/hard limits for max CPU usage in seconds"),
  #endif
  #if defined (RLIMIT_DATA) || defined (RLIMIT_VMEM) || defined (RLIMIT_AS)
  AP_INIT_TAKE12("RLimitMEM", set_limit_mem,
    (void*)APR_OFFSETOF(core_dir_config, limit_mem),
    OR_ALL, "Soft/hard limits for max memory usage per process"),
  #else
  AP_INIT_TAKE12("RLimitMEM", no_set_limit, NULL,
    OR_ALL, "Soft/hard limits for max memory usage per process"),
  #endif
  #ifdef RLIMIT_NPROC
  AP_INIT_TAKE12("RLimitNPROC", set_limit_nproc,
    (void*)APR_OFFSETOF(core_dir_config, limit_nproc),
    OR_ALL, "soft/hard limits for max number of processes per uid"),
  #else
  AP_INIT_TAKE12("RLimitNPROC", no_set_limit, NULL,
     OR_ALL, "soft/hard limits for max number of processes per uid"),
  #endif
  
  AP_INIT_RAW_ARGS("RegexDefaultOptions", set_regex_default_options, NULL, RSRC_CONF,
                   "default options for regexes (prefixed by '+' to add, '-' to del)"),
  
  /* internal recursion stopper */
  AP_INIT_TAKE12("LimitInternalRecursion", set_recursion_limit, NULL, RSRC_CONF,
                "maximum recursion depth of internal redirects and subrequests"),
  
  AP_INIT_FLAG("CGIPassAuth", set_cgi_pass_auth, NULL, OR_AUTHCFG,
               "Controls whether HTTP authorization headers, normally hidden, will "
               "be passed to scripts"),
  AP_INIT_TAKE2("CGIVar", set_cgi_var, NULL, OR_FILEINFO,
                "Controls how some CGI variables are set"),
  AP_INIT_FLAG("QualifyRedirectURL", set_qualify_redirect_url, NULL, OR_FILEINFO,
               "Controls whether the REDIRECT_URL environment variable is fully "
               "qualified"),
  AP_INIT_FLAG("StrictHostCheck", set_core_server_flag, 
               (void *)APR_OFFSETOF(core_server_config, strict_host_check),  
               RSRC_CONF,
               "Controls whether a hostname match is required"),
  AP_INIT_TAKE1("ForceType", ap_set_string_slot_lower,
         (void *)APR_OFFSETOF(core_dir_config, mime_type), OR_FILEINFO,
       "a mime type that overrides other configured type"),
  AP_INIT_TAKE1("SetHandler", set_sethandler, NULL, OR_FILEINFO,
     "a handler name that overrides any other configured handler"),
  AP_INIT_TAKE1("SetOutputFilter", ap_set_string_slot,
         (void *)APR_OFFSETOF(core_dir_config, output_filters), OR_FILEINFO,
     "filter (or ; delimited list of filters) to be run on the request content"),
  AP_INIT_TAKE1("SetInputFilter", ap_set_string_slot,
         (void *)APR_OFFSETOF(core_dir_config, input_filters), OR_FILEINFO,
     "filter (or ; delimited list of filters) to be run on the request body"),
  AP_INIT_TAKE1("AllowEncodedSlashes", set_allow2f, NULL, RSRC_CONF,
               "Allow URLs containing '/' encoded as '%2F'"),
  
  /* scoreboard.c directives */
  AP_INIT_TAKE1("ScoreBoardFile", ap_set_scoreboard, NULL, RSRC_CONF,
                "A file for Apache to maintain runtime process management information"),
  AP_INIT_FLAG("ExtendedStatus", ap_set_extended_status, NULL, RSRC_CONF,
               "\"On\" to track extended status information, \"Off\" to disable"),
  AP_INIT_FLAG("SeeRequestTail", ap_set_reqtail, NULL, RSRC_CONF,
               "For extended status, \"On\" to see the last 63 chars of "
               "the request line, \"Off\" (default) to see the first 63"),
  
  /*
   * These are default configuration directives that mpms can/should
   * pay attention to.
   * XXX These are not for all platforms, and even some Unix MPMs might not want
   * some directives.
   */
  AP_INIT_TAKE1("PidFile",  ap_mpm_set_pidfile, NULL, RSRC_CONF,
                "A file for logging the server process ID"),
  AP_INIT_TAKE1("MaxRequestsPerChild", ap_mpm_set_max_requests, NULL, RSRC_CONF,
                "Maximum number of connections a particular child serves before "
                "dying. (DEPRECATED, use MaxConnectionsPerChild)"),
  AP_INIT_TAKE1("MaxConnectionsPerChild", ap_mpm_set_max_requests, NULL, RSRC_CONF,
                "Maximum number of connections a particular child serves before dying."),
  AP_INIT_TAKE1("CoreDumpDirectory", ap_mpm_set_coredumpdir, NULL, RSRC_CONF,
                "The location of the directory Apache changes to before dumping core"),
  AP_INIT_TAKE1("MaxMemFree", ap_mpm_set_max_mem_free, NULL, RSRC_CONF,
                "Maximum number of 1k blocks a particular child's allocator may hold."),
  AP_INIT_TAKE1("ThreadStackSize", ap_mpm_set_thread_stacksize, NULL, RSRC_CONF,
                "Size in bytes of stack used by threads handling client connections"),
  #if AP_ENABLE_EXCEPTION_HOOK
  AP_INIT_TAKE1("EnableExceptionHook", ap_mpm_set_exception_hook, NULL, RSRC_CONF,
                "Controls whether exception hook may be called after a crash"),
  #endif
  AP_INIT_TAKE1("TraceEnable", set_trace_enable, NULL, RSRC_CONF,
                "'on' (default), 'off' or 'extended' to trace request body content"),
  AP_INIT_FLAG("MergeTrailers", set_merge_trailers, NULL, RSRC_CONF,
                "merge request trailers into request headers or not"),
  AP_INIT_ITERATE("HttpProtocolOptions", set_http_protocol_options, NULL, RSRC_CONF,
                  "'Allow0.9' or 'Require1.0' (default); "
                  "'RegisteredMethods' or 'LenientMethods' (default); "
                  "'Unsafe' or 'Strict' (default). Sets HTTP acceptance rules"),
  AP_INIT_ITERATE("RegisterHttpMethod", set_http_method, NULL, RSRC_CONF,
                  "Registers non-standard HTTP methods"),
  AP_INIT_FLAG("HttpContentLengthHeadZero", set_cl_head_zero, NULL, OR_OPTIONS,
    "whether to permit Content-Length of 0 responses to HEAD requests"),
  AP_INIT_FLAG("HttpExpectStrict", set_expect_strict, NULL, OR_OPTIONS,
    "whether to return a 417 if a client doesn't send 100-Continue"),
  AP_INIT_ITERATE("Protocols", set_protocols, NULL, RSRC_CONF,
                  "Controls which protocols are allowed"),
  AP_INIT_TAKE1("ProtocolsHonorOrder", set_protocols_honor_order, NULL, RSRC_CONF,
                "'off' (default) or 'on' to respect given order of protocols, "
                "by default the client specified order determines selection"),
  AP_INIT_TAKE1("AsyncFilter", set_async_filter, NULL, RSRC_CONF,
                "'network', 'connection' (default) or 'request' to limit the "
                "types of filters that support asynchronous handling"),
  AP_INIT_FLAG("MergeSlashes", set_core_server_flag, 
               (void *)APR_OFFSETOF(core_server_config, merge_slashes),  
               RSRC_CONF,
               "Controls whether consecutive slashes in the URI path are merged"),
  { NULL }
  };
  
  /*****************************************************************
   *
   * Core handlers for various phases of server operation...
   */
  
  AP_DECLARE_NONSTD(int) ap_core_translate(request_rec *r)
  {
      apr_status_t rv;
      char *path;
  
      /* XXX this seems too specific, this should probably become
       * some general-case test
       */
      if (r->proxyreq) {
          return HTTP_FORBIDDEN;
      }
      if (!r->uri || ((r->uri[0] != '/') && strcmp(r->uri, "*"))) {
          ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00126)
                       "Invalid URI in request '%s' '%s'", r->uri, r->the_request);
          return HTTP_BAD_REQUEST;
      }
  
      if (r->server->path
          && !strncmp(r->uri, r->server->path, r->server->pathlen)
          && (r->server->path[r->server->pathlen - 1] == '/'
              || r->uri[r->server->pathlen] == '/'
              || r->uri[r->server->pathlen] == '\0'))
      {
          path = r->uri + r->server->pathlen;
      }
      else {
          path = r->uri;
      }
      /*
       * Make sure that we do not mess up the translation by adding two
       * /'s in a row.  This happens under windows when the document
       * root ends with a /
       */
      /* skip all leading /'s (e.g. http://localhost///foo)
       * so we are looking at only the relative path.
       */
      while (*path == '/') {
          ++path;
      }
      if ((rv = apr_filepath_merge(&r->filename, ap_document_root(r), path,
                                   APR_FILEPATH_TRUENAME
                                 | APR_FILEPATH_SECUREROOT, r->pool))
                  != APR_SUCCESS) {
          ap_log_rerror(APLOG_MARK, APLOG_ERR, rv, r, APLOGNO(00127)
                       "Cannot map %s to file", r->the_request);
          return HTTP_FORBIDDEN;
      }
      r->canonical_filename = r->filename;
  
      return OK;
  }
  
  /*****************************************************************
   *
   * Test the filesystem name through directory_walk and file_walk
   */
  static int core_map_to_storage(request_rec *r)
  {
      int access_status;
  
      if ((access_status = ap_directory_walk(r))) {
          return access_status;
      }
  
      if ((access_status = ap_file_walk(r))) {
          return access_status;
      }
  
      return OK;
  }
  
  
  static int do_nothing(request_rec *r) { return OK; }
  
  static int core_override_type(request_rec *r)
  {
      core_dir_config *conf =
          (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      /* Check for overrides with ForceType / SetHandler
       */
      if (conf->mime_type && strcmp(conf->mime_type, "none"))
          ap_set_content_type(r, (char*) conf->mime_type);
  
      if (conf->expr_handler) { 
          const char *err;
          const char *val;
          val = ap_expr_str_exec(r, conf->expr_handler, &err);
          if (err) {
              ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(03154)
                            "Can't evaluate handler expression: %s", err);
              return HTTP_INTERNAL_SERVER_ERROR;
          }
  
          if (val != ap_strstr_c(val, "proxy:unix")) { 
              /* Retained for compatibility --  but not for UDS */
              char *tmp = apr_pstrdup(r->pool, val);
              ap_str_tolower(tmp);
              val = tmp;
          }
  
          if (strcmp(val, "none")) { 
              r->handler = val;
          }
      }
      else if (conf->handler && strcmp(conf->handler, "none")) { 
          r->handler = conf->handler;
      }
  
      /* Deal with the poor soul who is trying to force path_info to be
       * accepted within the core_handler, where they will let the subreq
       * address its contents.  This is toggled by the user in the very
       * beginning of the fixup phase (here!), so modules should override the user's
       * discretion in their own module fixup phase.  It is tristate, if
       * the user doesn't specify, the result is AP_REQ_DEFAULT_PATH_INFO.
       * (which the module may interpret to its own customary behavior.)
       * It won't be touched if the value is no longer AP_ACCEPT_PATHINFO_UNSET,
       * so any module changing the value prior to the fixup phase
       * OVERRIDES the user's choice.
       */
      if ((r->used_path_info == AP_REQ_DEFAULT_PATH_INFO)
          && (conf->accept_path_info != AP_ACCEPT_PATHINFO_UNSET)) {
          /* No module knew better, and the user coded AcceptPathInfo */
          r->used_path_info = conf->accept_path_info;
      }
  
      return OK;
  }
  
  static int default_handler(request_rec *r)
  {
      conn_rec *c = r->connection;
      apr_bucket_brigade *bb;
      apr_bucket *e;
      core_dir_config *d;
      int errstatus;
      apr_file_t *fd = NULL;
      apr_status_t status;
  
      d = (core_dir_config *)ap_get_core_module_config(r->per_dir_config);
  
      ap_allow_standard_methods(r, MERGE_ALLOW, M_GET, M_OPTIONS, M_POST, -1);
  
      /* If filters intend to consume the request body, they must
       * register an InputFilter to slurp the contents of the POST
       * data from the POST input stream.  It no longer exists when
       * the output filters are invoked by the default handler.
       */
      if ((errstatus = ap_discard_request_body(r)) != OK) {
          return errstatus;
      }
  
      if (r->method_number == M_GET || r->method_number == M_POST) {
          if (r->finfo.filetype == APR_NOFILE) {
              ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(00128)
                            "File does not exist: %s",
                            apr_pstrcat(r->pool, r->filename, r->path_info, NULL));
              return HTTP_NOT_FOUND;
          }
  
          /* Don't try to serve a dir.  Some OSs do weird things with
           * raw I/O on a dir.
           */
          if (r->finfo.filetype == APR_DIR) {
              ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(00129)
                            "Attempt to serve directory: %s", r->filename);
              return HTTP_NOT_FOUND;
          }
  
          if ((r->used_path_info != AP_REQ_ACCEPT_PATH_INFO) &&
              r->path_info && *r->path_info)
          {
              /* default to reject */
              ap_log_rerror(APLOG_MARK, APLOG_INFO, 0, r, APLOGNO(00130)
                            "File does not exist: %s",
                            apr_pstrcat(r->pool, r->filename, r->path_info, NULL));
              return HTTP_NOT_FOUND;
          }
  
          /* We understood the (non-GET) method, but it might not be legal for
             this particular resource. Check to see if the 'deliver_script'
             flag is set. If so, then we go ahead and deliver the file since
             it isn't really content (only GET normally returns content).
  
             Note: based on logic further above, the only possible non-GET
             method at this point is POST. In the future, we should enable
             script delivery for all methods.  */
          if (r->method_number != M_GET) {
              core_request_config *req_cfg;
  
              req_cfg = ap_get_core_module_config(r->request_config);
              if (!req_cfg->deliver_script) {
                  /* The flag hasn't been set for this request. Punt. */
                  ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00131)
                                "This resource does not accept the %s method.",
                                r->method);
                  return HTTP_METHOD_NOT_ALLOWED;
              }
          }
  
  
          if ((status = apr_file_open(&fd, r->filename, APR_READ | APR_BINARY
  #if APR_HAS_SENDFILE
                              | AP_SENDFILE_ENABLED(d->enable_sendfile)
  #endif
                                      , 0, r->pool)) != APR_SUCCESS) {
              ap_log_rerror(APLOG_MARK, APLOG_ERR, status, r, APLOGNO(00132)
                            "file permissions deny server access: %s", r->filename);
              return HTTP_FORBIDDEN;
          }
  
          ap_update_mtime(r, r->finfo.mtime);
          ap_set_last_modified(r);
          ap_set_etag_fd(r, fd);
          ap_set_accept_ranges(r);
          ap_set_content_length(r, r->finfo.size);
  
          bb = apr_brigade_create(r->pool, c->bucket_alloc);
  
          if ((errstatus = ap_meets_conditions(r)) != OK) {
              apr_file_close(fd);
              r->status = errstatus;
          }
          else {
              e = apr_brigade_insert_file(bb, fd, 0, r->finfo.size, r->pool);
  
  #if APR_HAS_MMAP
              if (d->enable_mmap == ENABLE_MMAP_OFF) {
                  (void)apr_bucket_file_enable_mmap(e, 0);
              }
  #endif
  #if APR_MAJOR_VERSION > 1 || (APU_MAJOR_VERSION == 1 && APU_MINOR_VERSION >= 6)
              if (d->read_buf_size) {
                  apr_bucket_file_set_buf_size(e, d->read_buf_size);
              }
  #endif
          }
  
          e = apr_bucket_eos_create(c->bucket_alloc);
          APR_BRIGADE_INSERT_TAIL(bb, e);
  
          status = ap_pass_brigade(r->output_filters, bb);
          apr_brigade_cleanup(bb);
  
          if (status == APR_SUCCESS
              || r->status != HTTP_OK
              || c->aborted) {
              return OK;
          }
          else {
              /* no way to know what type of error occurred */
              ap_log_rerror(APLOG_MARK, APLOG_DEBUG, status, r, APLOGNO(00133)
                            "default_handler: ap_pass_brigade returned %i",
                            status);
              return AP_FILTER_ERROR;
          }
      }
      else {              /* unusual method (not GET or POST) */
          if (r->method_number == M_INVALID) {
              /* See if this looks like an undecrypted SSL handshake attempt.
               * It's safe to look a couple bytes into the_request if it exists, as it's
               * always allocated at least MIN_LINE_ALLOC (80) bytes.
               */
              if (r->the_request
                  && r->the_request[0] == 0x16
                  && (r->the_request[1] == 0x2 || r->the_request[1] == 0x3)) {
                  ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00134)
                                "Invalid method in request %s - possible attempt to establish SSL connection on non-SSL port", r->the_request);
              } else {
                  ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(00135)
                                "Invalid method in request %s", r->the_request);
              }
              return HTTP_NOT_IMPLEMENTED;
          }
  
          if (r->method_number == M_OPTIONS) {
              return ap_send_http_options(r);
          }
          return HTTP_METHOD_NOT_ALLOWED;
      }
  }
  
  /* Optional function coming from mod_logio, used for logging of output
   * traffic
   */
  APR_OPTIONAL_FN_TYPE(ap_logio_add_bytes_out) *ap__logio_add_bytes_out;
  APR_OPTIONAL_FN_TYPE(authz_some_auth_required) *ap__authz_ap_some_auth_required;
  
  /* Insist that at least one module will undertake to provide system
   * security by dropping startup privileges.
   */
  static int sys_privileges = 0;
  AP_DECLARE(int) ap_sys_privileges_handlers(int inc)
  {
      sys_privileges += inc;
      return sys_privileges;
  }
  
  static int check_errorlog_dir(apr_pool_t *p, server_rec *s)
  {
      if (!s->error_fname || s->error_fname[0] == '|'
          || s->errorlog_provider != NULL) {
          return APR_SUCCESS;
      }
      else {
          char *abs = ap_server_root_relative(p, s->error_fname);
          char *dir = ap_make_dirstr_parent(p, abs);
          apr_finfo_t finfo;
          apr_status_t rv = apr_stat(&finfo, dir, APR_FINFO_TYPE, p);
          if (rv == APR_SUCCESS && finfo.filetype != APR_DIR)
              rv = APR_ENOTDIR;
          if (rv != APR_SUCCESS) {
              const char *desc = "main error log";
              if (s->defn_name)
                  desc = apr_psprintf(p, "error log of vhost defined at %s:%d",
                                      s->defn_name, s->defn_line_number);
              ap_log_error(APLOG_MARK, APLOG_STARTUP|APLOG_EMERG, rv,
                            ap_server_conf, APLOGNO(02291)
                           "Cannot access directory '%s' for %s", dir, desc);
              return !OK;
          }
      }
      return OK;
  }
  
  static int core_check_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s)
  {
      int rv = OK;
      while (s) {
          if (check_errorlog_dir(ptemp, s) != OK)
              rv = !OK;
          s = s->next;
      }
      return rv;
  }
  
  
  static int core_pre_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp)
  {
      ap_mutex_init(pconf);
  
      if (!saved_server_config_defines)
          init_config_defines(pconf);
      apr_pool_cleanup_register(pconf, NULL, reset_config, apr_pool_cleanup_null);
  
      ap_regcomp_set_default_cflags(AP_REG_DEFAULT);
  
      mpm_common_pre_config(pconf);
  
      return OK;
  }
  
  static int core_post_config(apr_pool_t *pconf, apr_pool_t *plog, apr_pool_t *ptemp, server_rec *s)
  {
      ap__logio_add_bytes_out = APR_RETRIEVE_OPTIONAL_FN(ap_logio_add_bytes_out);
      ident_lookup = APR_RETRIEVE_OPTIONAL_FN(ap_ident_lookup);
      ap__authz_ap_some_auth_required = APR_RETRIEVE_OPTIONAL_FN(authz_some_auth_required);
      authn_ap_auth_type = APR_RETRIEVE_OPTIONAL_FN(authn_ap_auth_type);
      authn_ap_auth_name = APR_RETRIEVE_OPTIONAL_FN(authn_ap_auth_name);
      access_compat_ap_satisfies = APR_RETRIEVE_OPTIONAL_FN(access_compat_ap_satisfies);
  
      set_banner(pconf);
      ap_setup_make_content_type(pconf);
      ap_setup_auth_internal(ptemp);
      ap_setup_ssl_optional_fns(pconf);
      if (!sys_privileges) {
          ap_log_error(APLOG_MARK, APLOG_CRIT, 0, NULL, APLOGNO(00136)
                       "Server MUST relinquish startup privileges before "
                       "accepting connections.  Please ensure mod_unixd "
                       "or other system security module is loaded.");
          return !OK;
      }
      apr_pool_cleanup_register(pconf, NULL, ap_mpm_end_gen_helper,
                                apr_pool_cleanup_null);
      return OK;
  }
  
  static void core_insert_filter(request_rec *r)
  {
      core_dir_config *conf = (core_dir_config *)
                              ap_get_core_module_config(r->per_dir_config);
      const char *filter, *filters = conf->output_filters;
  
      if (filters) {
          while (*filters && (filter = ap_getword(r->pool, &filters, ';'))) {
              ap_add_output_filter(filter, NULL, r, r->connection);
          }
      }
  
      filters = conf->input_filters;
      if (filters) {
          while (*filters && (filter = ap_getword(r->pool, &filters, ';'))) {
              ap_add_input_filter(filter, NULL, r, r->connection);
          }
      }
  }
  
  static apr_size_t num_request_notes = AP_NUM_STD_NOTES;
  
  static apr_status_t reset_request_notes(void *dummy)
  {
      num_request_notes = AP_NUM_STD_NOTES;
      return APR_SUCCESS;
  }
  
  AP_DECLARE(apr_size_t) ap_register_request_note(void)
  {
      apr_pool_cleanup_register(apr_hook_global_pool, NULL, reset_request_notes,
                                apr_pool_cleanup_null);
      return num_request_notes++;
  }
  
  AP_DECLARE(void **) ap_get_request_note(request_rec *r, apr_size_t note_num)
  {
      core_request_config *req_cfg;
  
      if (note_num >= num_request_notes) {
          return NULL;
      }
  
      req_cfg = (core_request_config *)
          ap_get_core_module_config(r->request_config);
  
      if (!req_cfg) {
          return NULL;
      }
  
      return &(req_cfg->notes[note_num]);
  }
  
  AP_DECLARE(apr_socket_t *) ap_get_conn_socket(conn_rec *c)
  {
      conn_config_t *conn_config = ap_get_core_module_config(c->conn_config);
  
      return AP_CORE_DEFAULT(conn_config, socket, NULL);
  }
  
  static int core_create_req(request_rec *r)
  {
      /* Alloc the config struct and the array of request notes in
       * a single block for efficiency
       */
      core_request_config *req_cfg;
  
      req_cfg = apr_pcalloc(r->pool, sizeof(core_request_config) +
                            sizeof(void *) * num_request_notes);
      req_cfg->notes = (void **)((char *)req_cfg + sizeof(core_request_config));
  
      /* ### temporarily enable script delivery as the default */
      req_cfg->deliver_script = 1;
  
      if (r->main) {
          core_request_config *main_req_cfg = (core_request_config *)
              ap_get_core_module_config(r->main->request_config);
          req_cfg->bb = main_req_cfg->bb;
      }
      else {
          req_cfg->bb = apr_brigade_create(r->pool, r->connection->bucket_alloc);
      }
  
      ap_set_core_module_config(r->request_config, req_cfg);
  
      return OK;
  }
  
  static int core_create_proxy_req(request_rec *r, request_rec *pr)
  {
      return core_create_req(pr);
  }
  
  static conn_rec *core_create_conn(apr_pool_t *ptrans, server_rec *s,
                                    apr_socket_t *csd, long id, void *sbh,
                                    apr_bucket_alloc_t *alloc)
  {
      apr_status_t rv;
      apr_pool_t *pool;
      conn_rec *c = (conn_rec *) apr_pcalloc(ptrans, sizeof(conn_rec));
      core_server_config *sconf = ap_get_core_module_config(s->module_config);
  
      c->sbh = sbh;
      ap_update_child_status(c->sbh, SERVER_BUSY_READ, NULL);
  
      /* Got a connection structure, so initialize what fields we can
       * (the rest are zeroed out by pcalloc).
       */
      apr_pool_create(&pool, ptrans);
      apr_pool_tag(pool, "master_conn");
      c->pool = pool;
  
      c->conn_config = ap_create_conn_config(c->pool);
      c->notes = apr_table_make(c->pool, 5);
      c->slaves = apr_array_make(c->pool, 20, sizeof(conn_slave_rec *));
      c->requests = apr_array_make(c->pool, 20, sizeof(request_rec *));
  
      if ((rv = apr_socket_addr_get(&c->local_addr, APR_LOCAL, csd))
          != APR_SUCCESS) {
          ap_log_error(APLOG_MARK, APLOG_INFO, rv, s, APLOGNO(00137)
                       "apr_socket_addr_get(APR_LOCAL)");
          apr_socket_close(csd);
          return NULL;
      }
      if (apr_sockaddr_ip_get(&c->local_ip, c->local_addr)) {
  #if APR_HAVE_SOCKADDR_UN
          if (c->local_addr->family == APR_UNIX) {
              c->local_ip = apr_pstrndup(c->pool, c->local_addr->ipaddr_ptr,
                                         c->local_addr->ipaddr_len);
          }
          else
  #endif
          c->local_ip = apr_pstrdup(c->pool, "unknown");
      }
  
      if ((rv = apr_socket_addr_get(&c->client_addr, APR_REMOTE, csd))
          != APR_SUCCESS) {
          ap_log_error(APLOG_MARK, APLOG_INFO, rv, s, APLOGNO(00138)
                       "apr_socket_addr_get(APR_REMOTE)");
          apr_socket_close(csd);
          return NULL;
      }
      if (apr_sockaddr_ip_get(&c->client_ip, c->client_addr)) {
  #if APR_HAVE_SOCKADDR_UN
          if (c->client_addr->family == APR_UNIX) {
              c->client_ip = apr_pstrndup(c->pool, c->client_addr->ipaddr_ptr,
                                          c->client_addr->ipaddr_len);
          }
          else
  #endif
          c->client_ip = apr_pstrdup(c->pool, "unknown");
      }
  
      c->base_server = s;
  
      c->id = id;
      c->bucket_alloc = alloc;
      c->async_filter = sconf->async_filter;
  
      c->clogging_input_filters = 0;
  
      if (sconf->conn_log_level) {
          int i;
          conn_log_config *conf;
          const struct ap_logconf *log = NULL;
          struct ap_logconf *merged;
  
          for (i = 0; i < sconf->conn_log_level->nelts; i++) {
              conf = APR_ARRAY_IDX(sconf->conn_log_level, i, conn_log_config *);
              if (apr_ipsubnet_test(conf->subnet, c->client_addr))
                  log = &conf->log;
          }
          if (log) {
              merged = ap_new_log_config(c->pool, log);
              ap_merge_log_config(&s->log, merged);
              c->log = merged;
          }
      }
  
      return c;
  }
  
  static int core_pre_connection(conn_rec *c, void *csd)
  {
      conn_config_t *conn_config;
      apr_status_t rv;
  
      /* only the master connection talks to the network */
      if (c->master) {
          return DONE;
      }
  
      /* The Nagle algorithm says that we should delay sending partial
       * packets in hopes of getting more data.  We don't want to do
       * this; we are not telnet.  There are bad interactions between
       * persistent connections and Nagle's algorithm that have very severe
       * performance penalties.  (Failing to disable Nagle is not much of a
       * problem with simple HTTP.)
       */
      rv = apr_socket_opt_set(csd, APR_TCP_NODELAY, 1);
      if (rv != APR_SUCCESS && rv != APR_ENOTIMPL) {
          /* expected cause is that the client disconnected already,
           * hence the debug level
           */
          ap_log_cerror(APLOG_MARK, APLOG_DEBUG, rv, c, APLOGNO(00139)
                        "apr_socket_opt_set(APR_TCP_NODELAY)");
      }
  
      /* The core filter requires the timeout mode to be set, which
       * incidentally sets the socket to be nonblocking.  If this
       * is not initialized correctly, Linux - for example - will
       * be initially blocking, while Solaris will be non blocking
       * and any initial read will fail.
       */
      rv = apr_socket_timeout_set(csd, c->base_server->timeout);
      if (rv != APR_SUCCESS) {
          /* expected cause is that the client disconnected already */
          ap_log_cerror(APLOG_MARK, APLOG_DEBUG, rv, c, APLOGNO(00140)
                        "apr_socket_timeout_set");
      }
  
      conn_config = apr_pcalloc(c->pool, sizeof(*conn_config));
      conn_config->socket = csd;
      ap_set_core_module_config(c->conn_config, conn_config);
  
      ap_add_input_filter_handle(ap_core_input_filter_handle, NULL, NULL, c);
      ap_add_output_filter_handle(ap_core_output_filter_handle, NULL, NULL, c);
  
      return DONE;
  }
  
  AP_CORE_DECLARE(conn_rec *) ap_create_slave_connection(conn_rec *c)
  {
      apr_pool_t *pool;
      conn_slave_rec *new;
      conn_rec *sc = (conn_rec *) apr_palloc(c->pool, sizeof(conn_rec));
  
      apr_pool_create(&pool, c->pool);
      apr_pool_tag(pool, "slave_conn");
      memcpy(sc, c, sizeof(conn_rec));
      sc->slaves = NULL;
      sc->master = c;
      sc->input_filters = NULL;
      sc->output_filters = NULL;
      sc->filter_conn_ctx = NULL;
      sc->pool = pool;
      new = apr_array_push(c->slaves);
      new->c = sc;
      return sc;
  }
  
  AP_DECLARE(int) ap_state_query(int query)
  {
      switch (query) {
      case AP_SQ_MAIN_STATE:
          return ap_main_state;
      case AP_SQ_RUN_MODE:
          return ap_run_mode;
      case AP_SQ_CONFIG_GEN:
          return ap_config_generation;
      default:
          return AP_SQ_NOT_SUPPORTED;
      }
  }
  
  AP_DECLARE(char *) ap_state_dir_relative(apr_pool_t *p, const char *file)
  {
      char *newpath = NULL;
      apr_status_t rv;
      const char *state_dir;
  
      state_dir = core_state_dir
          ? core_state_dir
          : ap_server_root_relative(p, DEFAULT_REL_STATEDIR);
  
      rv = apr_filepath_merge(&newpath, state_dir, file, APR_FILEPATH_TRUENAME, p);
      if (newpath && (rv == APR_SUCCESS || APR_STATUS_IS_EPATHWILD(rv)
                                        || APR_STATUS_IS_ENOENT(rv)
                                        || APR_STATUS_IS_ENOTDIR(rv))) {
          return newpath;
      }
      else {
          return NULL;
      }
  }
  
  
  static apr_random_t *rng = NULL;
  #if APR_HAS_THREADS
  static apr_thread_mutex_t *rng_mutex = NULL;
  #endif
  
  static void core_child_init(apr_pool_t *pchild, server_rec *s)
  {
      apr_proc_t proc;
  #if APR_HAS_THREADS
      {
          int threaded_mpm;
          if (ap_mpm_query(AP_MPMQ_IS_THREADED, &threaded_mpm) == APR_SUCCESS
              && threaded_mpm)
          {
              apr_thread_mutex_create(&rng_mutex, APR_THREAD_MUTEX_DEFAULT, pchild);
          }
      }
  #endif
      /* The MPMs use plain fork() and not apr_proc_fork(), so we have to call
       * apr_random_after_fork() manually in the child
       */
      proc.pid = getpid();
      apr_random_after_fork(&proc);
  }
  
  static void core_optional_fn_retrieve(void)
  {
      ap_init_scoreboard(NULL);
  }
  
  AP_CORE_DECLARE(void) ap_random_parent_after_fork(void)
  {
      /*
       * To ensure that the RNG state in the parent changes after the fork, we
       * pull some data from the RNG and discard it. This ensures that the RNG
       * states in the children are different even after the pid wraps around.
       * As we only use apr_random for insecure random bytes, pulling 2 bytes
       * should be enough.
       * XXX: APR should probably have some dedicated API to do this, but it
       * XXX: currently doesn't.
       */
      apr_uint16_t data;
      apr_random_insecure_bytes(rng, &data, sizeof(data));
  }
  
  AP_CORE_DECLARE(void) ap_init_rng(apr_pool_t *p)
  {
      unsigned char seed[8];
      apr_status_t rv;
      rng = apr_random_standard_new(p);
      do {
          rv = apr_generate_random_bytes(seed, sizeof(seed));
          if (rv != APR_SUCCESS)
              goto error;
          apr_random_add_entropy(rng, seed, sizeof(seed));
          rv = apr_random_insecure_ready(rng);
      } while (rv == APR_ENOTENOUGHENTROPY);
      if (rv == APR_SUCCESS)
          return;
  error:
      ap_log_error(APLOG_MARK, APLOG_CRIT, rv, NULL, APLOGNO(00141)
                   "Could not initialize random number generator");
      exit(1);
  }
  
  AP_DECLARE(void) ap_random_insecure_bytes(void *buf, apr_size_t size)
  {
  #if APR_HAS_THREADS
      if (rng_mutex)
          apr_thread_mutex_lock(rng_mutex);
  #endif
      /* apr_random_insecure_bytes can only fail with APR_ENOTENOUGHENTROPY,
       * and we have ruled that out during initialization. Therefore we don't
       * need to check the return code.
       */
      apr_random_insecure_bytes(rng, buf, size);
  #if APR_HAS_THREADS
      if (rng_mutex)
          apr_thread_mutex_unlock(rng_mutex);
  #endif
  }
  
  /*
   * Finding a random number in a range.
   *      n' = a + n(b-a+1)/(M+1)
   * where:
   *      n' = random number in range
   *      a  = low end of range
   *      b  = high end of range
   *      n  = random number of 0..M
   *      M  = maxint
   * Algorithm 'borrowed' from PHP's rand() function.
   */
  #define RAND_RANGE(__n, __min, __max, __tmax) \
  (__n) = (__min) + (long) ((double) ((__max) - (__min) + 1.0) * ((__n) / ((__tmax) + 1.0)))
  AP_DECLARE(apr_uint32_t) ap_random_pick(apr_uint32_t min, apr_uint32_t max)
  {
      apr_uint32_t number;
  #if (!__GNUC__ || __GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8) || \
       !__sparc__ || APR_SIZEOF_VOIDP != 8)
      /* This triggers a gcc bug on sparc/64bit with gcc < 4.8, PR 52900 */
      if (max < 16384) {
          apr_uint16_t num16;
          ap_random_insecure_bytes(&num16, sizeof(num16));
          RAND_RANGE(num16, min, max, APR_UINT16_MAX);
          number = num16;
      }
      else
  #endif
      {
          ap_random_insecure_bytes(&number, sizeof(number));
          RAND_RANGE(number, min, max, APR_UINT32_MAX);
      }
      return number;
  }
  
  static apr_status_t core_insert_network_bucket(conn_rec *c,
                                                 apr_bucket_brigade *bb,
                                                 apr_socket_t *socket)
  {
      apr_bucket *e = apr_bucket_socket_create(socket, c->bucket_alloc);
      APR_BRIGADE_INSERT_TAIL(bb, e);
      return APR_SUCCESS;
  }
  
  static apr_status_t core_dirwalk_stat(apr_finfo_t *finfo, request_rec *r,
                                        apr_int32_t wanted) 
  {
      return apr_stat(finfo, r->filename, wanted, r->pool);
  }
  
  static void core_dump_config(apr_pool_t *p, server_rec *s)
  {
      core_server_config *sconf = ap_get_core_module_config(s->module_config);
      apr_file_t *out = NULL;
      const char *tmp;
      const char **defines;
      int i;
      if (!ap_exists_config_define("DUMP_RUN_CFG"))
          return;
  
      apr_file_open_stdout(&out, p);
      apr_file_printf(out, "ServerRoot: \"%s\"\n", ap_server_root);
      tmp = ap_server_root_relative(p, sconf->ap_document_root);
      apr_file_printf(out, "Main DocumentRoot: \"%s\"\n", tmp);
      if (s->error_fname[0] != '|' && s->errorlog_provider == NULL)
          tmp = ap_server_root_relative(p, s->error_fname);
      else
          tmp = s->error_fname;
      apr_file_printf(out, "Main ErrorLog: \"%s\"\n", tmp);
      if (ap_scoreboard_fname) {
          tmp = ap_runtime_dir_relative(p, ap_scoreboard_fname);
          apr_file_printf(out, "ScoreBoardFile: \"%s\"\n", tmp);
      }
      ap_dump_mutexes(p, s, out);
      ap_mpm_dump_pidfile(p, out);
  
      defines = (const char **)ap_server_config_defines->elts;
      for (i = 0; i < ap_server_config_defines->nelts; i++) {
          const char *name = defines[i];
          const char *val = NULL;
          if (server_config_defined_vars)
             val = apr_table_get(server_config_defined_vars, name);
          if (val)
              apr_file_printf(out, "Define: %s=%s\n", name, val);
          else
              apr_file_printf(out, "Define: %s\n", name);
      }
  }
  
  static int core_upgrade_handler(request_rec *r)
  {
      conn_rec *c = r->connection;
      const char *upgrade;
  
      if (c->master) {
          /* Not possible to perform an HTTP/1.1 upgrade from a slave
           * connection. */
          return DECLINED;
      }
      
      upgrade = apr_table_get(r->headers_in, "Upgrade");
      if (upgrade && *upgrade) {
          const char *conn = apr_table_get(r->headers_in, "Connection");
          if (ap_find_token(r->pool, conn, "upgrade")) {
              apr_array_header_t *offers = NULL;
              const char *err;
              
              err = ap_parse_token_list_strict(r->pool, upgrade, &offers, 0);
              if (err) {
                  ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02910)
                                "parsing Upgrade header: %s", err);
                  return DECLINED;
              }
              
              if (offers && offers->nelts > 0) {
                  const char *protocol = ap_select_protocol(c, r, NULL, offers);
                  if (protocol && strcmp(protocol, ap_get_protocol(c))) {
                      ap_log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r, APLOGNO(02909)
                                    "Upgrade selects '%s'", protocol);
                      /* Let the client know what we are upgrading to. */
                      apr_table_clear(r->headers_out);
                      apr_table_setn(r->headers_out, "Upgrade", protocol);
                      apr_table_setn(r->headers_out, "Connection", "Upgrade");
                      
                      r->status = HTTP_SWITCHING_PROTOCOLS;
                      r->status_line = ap_get_status_line(r->status);
                      ap_send_interim_response(r, 1);
  
                      ap_switch_protocol(c, r, r->server, protocol);
  
                      /* make sure httpd closes the connection after this */
                      c->keepalive = AP_CONN_CLOSE;
                      return DONE;
                  }
              }
          }
      }
      else if (!c->keepalives) {
          /* first request on a master connection, if we have protocols other
           * than the current one enabled here, announce them to the
           * client. If the client is already talking a protocol with requests
           * on slave connections, leave it be. */
          const apr_array_header_t *upgrades;
          ap_get_protocol_upgrades(c, r, NULL, 0, &upgrades);
          if (upgrades && upgrades->nelts > 0) {
              char *protocols = apr_array_pstrcat(r->pool, upgrades, ',');
              apr_table_setn(r->headers_out, "Upgrade", protocols);
              apr_table_setn(r->headers_out, "Connection", "Upgrade");
          }
      }
      
      return DECLINED;
  }
  
  static int core_upgrade_storage(request_rec *r)
  {
      if ((r->method_number == M_OPTIONS) && r->uri && (r->uri[0] == '*') &&
          (r->uri[1] == '\0')) {
          return core_upgrade_handler(r);
      }
      return DECLINED;
  }
  
  static void register_hooks(apr_pool_t *p)
  {
      errorlog_hash = apr_hash_make(p);
      ap_register_log_hooks(p);
      ap_register_config_hooks(p);
      ap_expr_init(p);
  
      /* create_connection and pre_connection should always be hooked
       * APR_HOOK_REALLY_LAST by core to give other modules the opportunity
       * to install alternate network transports and stop other functions
       * from being run.
       */
      ap_hook_create_connection(core_create_conn, NULL, NULL,
                                APR_HOOK_REALLY_LAST);
      ap_hook_pre_connection(core_pre_connection, NULL, NULL,
                             APR_HOOK_REALLY_LAST);
  
      ap_hook_pre_config(core_pre_config, NULL, NULL, APR_HOOK_REALLY_FIRST);
      ap_hook_post_config(core_post_config,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_check_config(core_check_config,NULL,NULL,APR_HOOK_FIRST);
      ap_hook_test_config(core_dump_config,NULL,NULL,APR_HOOK_FIRST);
      ap_hook_translate_name(ap_core_translate,NULL,NULL,APR_HOOK_REALLY_LAST);
      ap_hook_map_to_storage(core_upgrade_storage,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_map_to_storage(core_map_to_storage,NULL,NULL,APR_HOOK_REALLY_LAST);
      ap_hook_open_logs(ap_open_logs,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_child_init(core_child_init,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_child_init(ap_logs_child_init,NULL,NULL,APR_HOOK_MIDDLE);
      ap_hook_handler(core_upgrade_handler,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_handler(default_handler,NULL,NULL,APR_HOOK_REALLY_LAST);
      /* FIXME: I suspect we can eliminate the need for these do_nothings - Ben */
      ap_hook_type_checker(do_nothing,NULL,NULL,APR_HOOK_REALLY_LAST);
      ap_hook_fixups(core_override_type,NULL,NULL,APR_HOOK_REALLY_FIRST);
      ap_hook_create_request(core_create_req, NULL, NULL, APR_HOOK_MIDDLE);
      APR_OPTIONAL_HOOK(proxy, create_req, core_create_proxy_req, NULL, NULL,
                        APR_HOOK_MIDDLE);
      ap_hook_pre_mpm(ap_create_scoreboard, NULL, NULL, APR_HOOK_MIDDLE);
      ap_hook_child_status(ap_core_child_status, NULL, NULL, APR_HOOK_MIDDLE);
      ap_hook_insert_network_bucket(core_insert_network_bucket, NULL, NULL,
                                    APR_HOOK_REALLY_LAST);
      ap_hook_dirwalk_stat(core_dirwalk_stat, NULL, NULL, APR_HOOK_REALLY_LAST);
      ap_hook_open_htaccess(ap_open_htaccess, NULL, NULL, APR_HOOK_REALLY_LAST);
      ap_hook_optional_fn_retrieve(core_optional_fn_retrieve, NULL, NULL,
                                   APR_HOOK_MIDDLE);
  
      ap_hook_input_pending(ap_filter_input_pending, NULL, NULL,
                            APR_HOOK_MIDDLE);
      ap_hook_output_pending(ap_filter_output_pending, NULL, NULL,
                             APR_HOOK_MIDDLE);
  
      /* register the core's insert_filter hook and register core-provided
       * filters
       */
      ap_hook_insert_filter(core_insert_filter, NULL, NULL, APR_HOOK_MIDDLE);
  
      ap_core_input_filter_handle =
          ap_register_input_filter("CORE_IN", ap_core_input_filter,
                                   NULL, AP_FTYPE_NETWORK);
      ap_content_length_filter_handle =
          ap_register_output_filter("CONTENT_LENGTH", ap_content_length_filter,
                                    NULL, AP_FTYPE_PROTOCOL);
      ap_core_output_filter_handle =
          ap_register_output_filter("CORE", ap_core_output_filter,
                                    NULL, AP_FTYPE_NETWORK);
      ap_subreq_core_filter_handle =
          ap_register_output_filter("SUBREQ_CORE", ap_sub_req_output_filter,
                                    NULL, AP_FTYPE_CONTENT_SET);
      ap_old_write_func =
          ap_register_output_filter("OLD_WRITE", ap_old_write_filter,
                                    NULL, AP_FTYPE_RESOURCE - 10);
  }
  
  AP_DECLARE_MODULE(core) = {
      MPM20_MODULE_STUFF,
      AP_PLATFORM_REWRITE_ARGS_HOOK, /* hook to run before apache parses args */
      create_core_dir_config,       /* create per-directory config structure */
      merge_core_dir_configs,       /* merge per-directory config structures */
      create_core_server_config,    /* create per-server config structure */
      merge_core_server_configs,    /* merge per-server config structures */
      core_cmds,                    /* command apr_table_t */
      register_hooks                /* register hooks */
  };
  