text: 
  /*
   * Copyright (C) Igor Sysoev
   */
  
  
  #include <ngx_config.h>
  #include <ngx_core.h>
  #include <ngx_http.h>
  
  
  typedef struct {
      ngx_array_t  *codes;        /* uintptr_t */
  
      ngx_uint_t    stack_size;
  
      ngx_flag_t    log;
      ngx_flag_t    uninitialized_variable_warn;
  } ngx_http_rewrite_loc_conf_t;
  
  
  static void *ngx_http_rewrite_create_loc_conf(ngx_conf_t *cf);
  static char *ngx_http_rewrite_merge_loc_conf(ngx_conf_t *cf,
      void *parent, void *child);
  static ngx_int_t ngx_http_rewrite_init(ngx_conf_t *cf);
  static char *ngx_http_rewrite(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
  static char *ngx_http_rewrite_return(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_rewrite_break(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char *ngx_http_rewrite_if(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char * ngx_http_rewrite_if_condition(ngx_conf_t *cf,
      ngx_http_rewrite_loc_conf_t *lcf);
  static char *ngx_http_rewrite_variable(ngx_conf_t *cf,
      ngx_http_rewrite_loc_conf_t *lcf, ngx_str_t *value);
  static char *ngx_http_rewrite_set(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  static char * ngx_http_rewrite_value(ngx_conf_t *cf,
      ngx_http_rewrite_loc_conf_t *lcf, ngx_str_t *value);
  
  
  static ngx_command_t  ngx_http_rewrite_commands[] = {
  
      { ngx_string("rewrite"),
        NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                         |NGX_CONF_TAKE23,
        ngx_http_rewrite,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("return"),
        NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                         |NGX_CONF_TAKE12,
        ngx_http_rewrite_return,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("break"),
        NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                         |NGX_CONF_NOARGS,
        ngx_http_rewrite_break,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("if"),
        NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_BLOCK|NGX_CONF_1MORE,
        ngx_http_rewrite_if,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("set"),
        NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF|NGX_HTTP_LIF_CONF
                         |NGX_CONF_TAKE2,
        ngx_http_rewrite_set,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("rewrite_log"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF
                          |NGX_HTTP_LIF_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_rewrite_loc_conf_t, log),
        NULL },
  
      { ngx_string("uninitialized_variable_warn"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_SIF_CONF|NGX_HTTP_LOC_CONF
                          |NGX_HTTP_LIF_CONF|NGX_CONF_FLAG,
        ngx_conf_set_flag_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_rewrite_loc_conf_t, uninitialized_variable_warn),
        NULL },
  
        ngx_null_command
  };
  
  
  static ngx_http_module_t  ngx_http_rewrite_module_ctx = {
      NULL,                                  /* preconfiguration */
      ngx_http_rewrite_init,                 /* postconfiguration */
  
      NULL,                                  /* create main configuration */
      NULL,                                  /* init main configuration */
  
      NULL,                                  /* create server configuration */
      NULL,                                  /* merge server configuration */
  
      ngx_http_rewrite_create_loc_conf,      /* create location configration */
      ngx_http_rewrite_merge_loc_conf        /* merge location configration */
  };
  
  
  ngx_module_t  ngx_http_rewrite_module = {
      NGX_MODULE_V1,
      &ngx_http_rewrite_module_ctx,          /* module context */
      ngx_http_rewrite_commands,             /* module directives */
      NGX_HTTP_MODULE,                       /* module type */
      NULL,                                  /* init master */
      NULL,                                  /* init module */
      NULL,                                  /* init process */
      NULL,                                  /* init thread */
      NULL,                                  /* exit thread */
      NULL,                                  /* exit process */
      NULL,                                  /* exit master */
      NGX_MODULE_V1_PADDING
  };
  
  
  static ngx_int_t
  ngx_http_rewrite_handler(ngx_http_request_t *r)
  {
      ngx_http_script_code_pt       code;
      ngx_http_script_engine_t     *e;
      ngx_http_rewrite_loc_conf_t  *rlcf;
  
      rlcf = ngx_http_get_module_loc_conf(r, ngx_http_rewrite_module);
  
      if (rlcf->codes == NULL) {
          return NGX_DECLINED;
      }
  
      e = ngx_pcalloc(r->pool, sizeof(ngx_http_script_engine_t));
      if (e == NULL) {
          return NGX_HTTP_INTERNAL_SERVER_ERROR;
      }
  
      e->sp = ngx_pcalloc(r->pool,
                          rlcf->stack_size * sizeof(ngx_http_variable_value_t));
      if (e->sp == NULL) {
          return NGX_HTTP_INTERNAL_SERVER_ERROR;
      }
  
      e->ip = rlcf->codes->elts;
      e->request = r;
      e->quote = 1;
      e->log = rlcf->log;
      e->status = NGX_DECLINED;
  
      while (*(uintptr_t *) e->ip) {
          code = *(ngx_http_script_code_pt *) e->ip;
          code(e);
      }
  
      if (e->status == NGX_DECLINED) {
          return NGX_DECLINED;
      }
  
      if (r->err_status == 0) {
          return e->status;
      }
  
      return r->err_status;
  }
  
  
  static ngx_int_t
  ngx_http_rewrite_var(ngx_http_request_t *r, ngx_http_variable_value_t *v,
      uintptr_t data)
  {
      ngx_http_variable_t          *var;
      ngx_http_core_main_conf_t    *cmcf;
      ngx_http_rewrite_loc_conf_t  *rlcf;
  
      rlcf = ngx_http_get_module_loc_conf(r, ngx_http_rewrite_module);
  
      if (rlcf->uninitialized_variable_warn == 0) {
          *v = ngx_http_variable_null_value;
          return NGX_OK;
      }
  
      cmcf = ngx_http_get_module_main_conf(r, ngx_http_core_module);
  
      var = cmcf->variables.elts;
  
      /*
       * the ngx_http_rewrite_module sets variables directly in r->variables,
       * and they should be handled by ngx_http_get_indexed_variable(),
       * so the handler is called only if the variable is not initialized
       */
  
      ngx_log_error(NGX_LOG_WARN, r->connection->log, 0,
                    "using uninitialized \"%V\" variable", &var[data].name);
  
      *v = ngx_http_variable_null_value;
  
      return NGX_OK;
  }
  
  
  static void *
  ngx_http_rewrite_create_loc_conf(ngx_conf_t *cf)
  {
      ngx_http_rewrite_loc_conf_t  *conf;
  
      conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_rewrite_loc_conf_t));
      if (conf == NULL) {
          return NULL;
      }
  
      conf->stack_size = NGX_CONF_UNSET_UINT;
      conf->log = NGX_CONF_UNSET;
      conf->uninitialized_variable_warn = NGX_CONF_UNSET;
  
      return conf;
  }
  
  
  static char *
  ngx_http_rewrite_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
  {
      ngx_http_rewrite_loc_conf_t *prev = parent;
      ngx_http_rewrite_loc_conf_t *conf = child;
  
      uintptr_t  *code;
  
      ngx_conf_merge_value(conf->log, prev->log, 0);
      ngx_conf_merge_value(conf->uninitialized_variable_warn,
                           prev->uninitialized_variable_warn, 1);
      ngx_conf_merge_uint_value(conf->stack_size, prev->stack_size, 10);
  
      if (conf->codes == NULL) {
          return NGX_CONF_OK;
      }
  
      if (conf->codes == prev->codes) {
          return NGX_CONF_OK;
      }
  
      code = ngx_array_push_n(conf->codes, sizeof(uintptr_t));
      if (code == NULL) {
          return NGX_CONF_ERROR;
      }
  
      *code = (uintptr_t) NULL;
  
      return NGX_CONF_OK;
  }
  
  
  static ngx_int_t
  ngx_http_rewrite_init(ngx_conf_t *cf)
  {
      ngx_http_handler_pt        *h;
      ngx_http_core_main_conf_t  *cmcf;
  
      cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);
  
      h = ngx_array_push(&cmcf->phases[NGX_HTTP_SERVER_REWRITE_PHASE].handlers);
      if (h == NULL) {
          return NGX_ERROR;
      }
  
      *h = ngx_http_rewrite_handler;
  
      h = ngx_array_push(&cmcf->phases[NGX_HTTP_REWRITE_PHASE].handlers);
      if (h == NULL) {
          return NGX_ERROR;
      }
  
      *h = ngx_http_rewrite_handler;
  
      return NGX_OK;
  }
  
  
  static char *
  ngx_http_rewrite(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_rewrite_loc_conf_t  *lcf = conf;
  
      ngx_str_t                         *value;
      ngx_uint_t                         last;
      ngx_regex_compile_t                rc;
      ngx_http_script_code_pt           *code;
      ngx_http_script_compile_t          sc;
      ngx_http_script_regex_code_t      *regex;
      ngx_http_script_regex_end_code_t  *regex_end;
      u_char                             errstr[NGX_MAX_CONF_ERRSTR];
  
      regex = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                         sizeof(ngx_http_script_regex_code_t));
      if (regex == NULL) {
          return NGX_CONF_ERROR;
      }
  
      ngx_memzero(regex, sizeof(ngx_http_script_regex_code_t));
  
      value = cf->args->elts;
  
      ngx_memzero(&rc, sizeof(ngx_regex_compile_t));
  
      rc.pattern = value[1];
      rc.err.len = NGX_MAX_CONF_ERRSTR;
      rc.err.data = errstr;
  
      /* TODO: NGX_REGEX_CASELESS */
  
      regex->regex = ngx_http_regex_compile(cf, &rc);
      if (regex->regex == NULL) {
          return NGX_CONF_ERROR;
      }
  
      regex->code = ngx_http_script_regex_start_code;
      regex->uri = 1;
      regex->name = value[1];
  
      if (value[2].data[value[2].len - 1] == '?') {
  
          /* the last "?" drops the original arguments */
          value[2].len--;
  
      } else {
          regex->add_args = 1;
      }
  
      last = 0;
  
      if (ngx_strncmp(value[2].data, "http://", sizeof("http://") - 1) == 0
          || ngx_strncmp(value[2].data, "https://", sizeof("https://") - 1) == 0
          || ngx_strncmp(value[2].data, "$scheme", sizeof("$scheme") - 1) == 0)
      {
          regex->status = NGX_HTTP_MOVED_TEMPORARILY;
          regex->redirect = 1;
          last = 1;
      }
  
      if (cf->args->nelts == 4) {
          if (ngx_strcmp(value[3].data, "last") == 0) {
              last = 1;
  
          } else if (ngx_strcmp(value[3].data, "break") == 0) {
              regex->break_cycle = 1;
              last = 1;
  
          } else if (ngx_strcmp(value[3].data, "redirect") == 0) {
              regex->status = NGX_HTTP_MOVED_TEMPORARILY;
              regex->redirect = 1;
              last = 1;
  
          } else if (ngx_strcmp(value[3].data, "permanent") == 0) {
              regex->status = NGX_HTTP_MOVED_PERMANENTLY;
              regex->redirect = 1;
              last = 1;
  
          } else {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "invalid parameter \"%V\"", &value[3]);
              return NGX_CONF_ERROR;
          }
      }
  
      ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
      sc.cf = cf;
      sc.source = &value[2];
      sc.lengths = &regex->lengths;
      sc.values = &lcf->codes;
      sc.variables = ngx_http_script_variables_count(&value[2]);
      sc.main = regex;
      sc.complete_lengths = 1;
      sc.compile_args = !regex->redirect;
  
      if (ngx_http_script_compile(&sc) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      regex = sc.main;
  
      regex->size = sc.size;
      regex->args = sc.args;
  
      if (sc.variables == 0 && !sc.dup_capture) {
          regex->lengths = NULL;
      }
  
      regex_end = ngx_http_script_add_code(lcf->codes,
                                        sizeof(ngx_http_script_regex_end_code_t),
                                        &regex);
      if (regex_end == NULL) {
          return NGX_CONF_ERROR;
      }
  
      regex_end->code = ngx_http_script_regex_end_code;
      regex_end->uri = regex->uri;
      regex_end->args = regex->args;
      regex_end->add_args = regex->add_args;
      regex_end->redirect = regex->redirect;
  
      if (last) {
          code = ngx_http_script_add_code(lcf->codes, sizeof(uintptr_t), &regex);
          if (code == NULL) {
              return NGX_CONF_ERROR;
          }
  
          *code = NULL;
      }
  
      regex->next = (u_char *) lcf->codes->elts + lcf->codes->nelts
                                                - (u_char *) regex;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_return(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_rewrite_loc_conf_t  *lcf = conf;
  
      u_char                            *p;
      ngx_str_t                         *value, *v;
      ngx_http_script_return_code_t     *ret;
      ngx_http_compile_complex_value_t   ccv;
  
      ret = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                       sizeof(ngx_http_script_return_code_t));
      if (ret == NULL) {
          return NGX_CONF_ERROR;
      }
  
      value = cf->args->elts;
  
      ngx_memzero(ret, sizeof(ngx_http_script_return_code_t));
  
      ret->code = ngx_http_script_return_code;
  
      p = value[1].data;
  
      ret->status = ngx_atoi(p, value[1].len);
  
      if (ret->status == (uintptr_t) NGX_ERROR) {
  
          if (cf->args->nelts == 2
              && (ngx_strncmp(p, "http://", sizeof("http://") - 1) == 0
                  || ngx_strncmp(p, "https://", sizeof("https://") - 1) == 0
                  || ngx_strncmp(p, "$scheme", sizeof("$scheme") - 1) == 0))
          {
              ret->status = NGX_HTTP_MOVED_TEMPORARILY;
              v = &value[1];
  
          } else {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "invalid return code \"%V\"", &value[1]);
              return NGX_CONF_ERROR;
          }
  
      } else {
  
          if (cf->args->nelts == 2) {
              return NGX_CONF_OK;
          }
  
          v = &value[2];
      }
  
      ngx_memzero(&ccv, sizeof(ngx_http_compile_complex_value_t));
  
      ccv.cf = cf;
      ccv.value = v;
      ccv.complex_value = &ret->text;
  
      if (ngx_http_compile_complex_value(&ccv) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_break(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_rewrite_loc_conf_t *lcf = conf;
  
      ngx_http_script_code_pt  *code;
  
      code = ngx_http_script_start_code(cf->pool, &lcf->codes, sizeof(uintptr_t));
      if (code == NULL) {
          return NGX_CONF_ERROR;
      }
  
      *code = ngx_http_script_break_code;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_if(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_rewrite_loc_conf_t  *lcf = conf;
  
      void                         *mconf;
      char                         *rv;
      u_char                       *elts;
      ngx_uint_t                    i;
      ngx_conf_t                    save;
      ngx_http_module_t            *module;
      ngx_http_conf_ctx_t          *ctx, *pctx;
      ngx_http_core_loc_conf_t     *clcf, *pclcf;
      ngx_http_script_if_code_t    *if_code;
      ngx_http_rewrite_loc_conf_t  *nlcf;
  
      ctx = ngx_pcalloc(cf->pool, sizeof(ngx_http_conf_ctx_t));
      if (ctx == NULL) {
          return NGX_CONF_ERROR;
      }
  
      pctx = cf->ctx;
      ctx->main_conf = pctx->main_conf;
      ctx->srv_conf = pctx->srv_conf;
  
      ctx->loc_conf = ngx_pcalloc(cf->pool, sizeof(void *) * ngx_http_max_module);
      if (ctx->loc_conf == NULL) {
          return NGX_CONF_ERROR;
      }
  
      for (i = 0; ngx_modules[i]; i++) {
          if (ngx_modules[i]->type != NGX_HTTP_MODULE) {
              continue;
          }
  
          module = ngx_modules[i]->ctx;
  
          if (module->create_loc_conf) {
  
              mconf = module->create_loc_conf(cf);
              if (mconf == NULL) {
                   return NGX_CONF_ERROR;
              }
  
              ctx->loc_conf[ngx_modules[i]->ctx_index] = mconf;
          }
      }
  
      pclcf = pctx->loc_conf[ngx_http_core_module.ctx_index];
  
      clcf = ctx->loc_conf[ngx_http_core_module.ctx_index];
      clcf->loc_conf = ctx->loc_conf;
      clcf->name = pclcf->name;
      clcf->noname = 1;
  
      if (ngx_http_add_location(cf, &pclcf->locations, clcf) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      if (ngx_http_rewrite_if_condition(cf, lcf) != NGX_CONF_OK) {
          return NGX_CONF_ERROR;
      }
  
      if_code = ngx_array_push_n(lcf->codes, sizeof(ngx_http_script_if_code_t));
      if (if_code == NULL) {
          return NGX_CONF_ERROR;
      }
  
      if_code->code = ngx_http_script_if_code;
  
      elts = lcf->codes->elts;
  
  
      /* the inner directives must be compiled to the same code array */
  
      nlcf = ctx->loc_conf[ngx_http_rewrite_module.ctx_index];
      nlcf->codes = lcf->codes;
  
  
      save = *cf;
      cf->ctx = ctx;
  
      if (pclcf->name.len == 0) {
          if_code->loc_conf = NULL;
          cf->cmd_type = NGX_HTTP_SIF_CONF;
  
      } else {
          if_code->loc_conf = ctx->loc_conf;
          cf->cmd_type = NGX_HTTP_LIF_CONF;
      }
  
      rv = ngx_conf_parse(cf, NULL);
  
      *cf = save;
  
      if (rv != NGX_CONF_OK) {
          return rv;
      }
  
  
      if (elts != lcf->codes->elts) {
          if_code = (ngx_http_script_if_code_t *)
                     ((u_char *) if_code + ((u_char *) lcf->codes->elts - elts));
      }
  
      if_code->next = (u_char *) lcf->codes->elts + lcf->codes->nelts
                                                  - (u_char *) if_code;
  
      /* the code array belong to parent block */
  
      nlcf->codes = NULL;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_if_condition(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf)
  {
      u_char                        *p;
      size_t                         len;
      ngx_str_t                     *value;
      ngx_uint_t                     cur, last;
      ngx_regex_compile_t            rc;
      ngx_http_script_code_pt       *code;
      ngx_http_script_file_code_t   *fop;
      ngx_http_script_regex_code_t  *regex;
      u_char                         errstr[NGX_MAX_CONF_ERRSTR];
  
      value = cf->args->elts;
      last = cf->args->nelts - 1;
  
      if (value[1].len < 1 || value[1].data[0] != '(') {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid condition \"%V\"", &value[1]);
          return NGX_CONF_ERROR;
      }
  
      if (value[1].len == 1) {
          cur = 2;
  
      } else {
          cur = 1;
          value[1].len--;
          value[1].data++;
      }
  
      if (value[last].len < 1 || value[last].data[value[last].len - 1] != ')') {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid condition \"%V\"", &value[last]);
          return NGX_CONF_ERROR;
      }
  
      if (value[last].len == 1) {
          last--;
  
      } else {
          value[last].len--;
          value[last].data[value[last].len] = '\0';
      }
  
      len = value[cur].len;
      p = value[cur].data;
  
      if (len > 1 && p[0] == '$') {
  
          if (cur != last && cur + 2 != last) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "invalid condition \"%V\"", &value[cur]);
              return NGX_CONF_ERROR;
          }
  
          if (ngx_http_rewrite_variable(cf, lcf, &value[cur]) != NGX_CONF_OK) {
              return NGX_CONF_ERROR;
          }
  
          if (cur == last) {
              return NGX_CONF_OK;
          }
  
          cur++;
  
          len = value[cur].len;
          p = value[cur].data;
  
          if (len == 1 && p[0] == '=') {
  
              if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
                  return NGX_CONF_ERROR;
              }
  
              code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                                sizeof(uintptr_t));
              if (code == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              *code = ngx_http_script_equal_code;
  
              return NGX_CONF_OK;
          }
  
          if (len == 2 && p[0] == '!' && p[1] == '=') {
  
              if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
                  return NGX_CONF_ERROR;
              }
  
              code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                                sizeof(uintptr_t));
              if (code == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              *code = ngx_http_script_not_equal_code;
              return NGX_CONF_OK;
          }
  
          if ((len == 1 && p[0] == '~')
              || (len == 2 && p[0] == '~' && p[1] == '*')
              || (len == 2 && p[0] == '!' && p[1] == '~')
              || (len == 3 && p[0] == '!' && p[1] == '~' && p[2] == '*'))
          {
              regex = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                           sizeof(ngx_http_script_regex_code_t));
              if (regex == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              ngx_memzero(regex, sizeof(ngx_http_script_regex_code_t));
  
              ngx_memzero(&rc, sizeof(ngx_regex_compile_t));
  
              rc.pattern = value[last];
              rc.options = (p[len - 1] == '*') ? NGX_REGEX_CASELESS : 0;
              rc.err.len = NGX_MAX_CONF_ERRSTR;
              rc.err.data = errstr;
  
              regex->regex = ngx_http_regex_compile(cf, &rc);
              if (regex->regex == NULL) {
                  return NGX_CONF_ERROR;
              }
  
              regex->code = ngx_http_script_regex_start_code;
              regex->next = sizeof(ngx_http_script_regex_code_t);
              regex->test = 1;
              if (p[0] == '!') {
                  regex->negative_test = 1;
              }
              regex->name = value[last];
  
              return NGX_CONF_OK;
          }
  
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "unexpected \"%V\" in condition", &value[cur]);
          return NGX_CONF_ERROR;
  
      } else if ((len == 2 && p[0] == '-')
                 || (len == 3 && p[0] == '!' && p[1] == '-'))
      {
          if (cur + 1 != last) {
              ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                                 "invalid condition \"%V\"", &value[cur]);
              return NGX_CONF_ERROR;
          }
  
          value[last].data[value[last].len] = '\0';
          value[last].len++;
  
          if (ngx_http_rewrite_value(cf, lcf, &value[last]) != NGX_CONF_OK) {
              return NGX_CONF_ERROR;
          }
  
          fop = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                            sizeof(ngx_http_script_file_code_t));
          if (fop == NULL) {
              return NGX_CONF_ERROR;
          }
  
          fop->code = ngx_http_script_file_code;
  
          if (p[1] == 'f') {
              fop->op = ngx_http_script_file_plain;
              return NGX_CONF_OK;
          }
  
          if (p[1] == 'd') {
              fop->op = ngx_http_script_file_dir;
              return NGX_CONF_OK;
          }
  
          if (p[1] == 'e') {
              fop->op = ngx_http_script_file_exists;
              return NGX_CONF_OK;
          }
  
          if (p[1] == 'x') {
              fop->op = ngx_http_script_file_exec;
              return NGX_CONF_OK;
          }
  
          if (p[0] == '!') {
              if (p[2] == 'f') {
                  fop->op = ngx_http_script_file_not_plain;
                  return NGX_CONF_OK;
              }
  
              if (p[2] == 'd') {
                  fop->op = ngx_http_script_file_not_dir;
                  return NGX_CONF_OK;
              }
  
              if (p[2] == 'e') {
                  fop->op = ngx_http_script_file_not_exists;
                  return NGX_CONF_OK;
              }
  
              if (p[2] == 'x') {
                  fop->op = ngx_http_script_file_not_exec;
                  return NGX_CONF_OK;
              }
          }
  
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid condition \"%V\"", &value[cur]);
          return NGX_CONF_ERROR;
      }
  
      ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                         "invalid condition \"%V\"", &value[cur]);
  
      return NGX_CONF_ERROR;
  }
  
  
  static char *
  ngx_http_rewrite_variable(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf,
      ngx_str_t *value)
  {
      ngx_int_t                    index;
      ngx_http_script_var_code_t  *var_code;
  
      value->len--;
      value->data++;
  
      index = ngx_http_get_variable_index(cf, value);
  
      if (index == NGX_ERROR) {
          return NGX_CONF_ERROR;
      }
  
      var_code = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                            sizeof(ngx_http_script_var_code_t));
      if (var_code == NULL) {
          return NGX_CONF_ERROR;
      }
  
      var_code->code = ngx_http_script_var_code;
      var_code->index = index;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_set(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_http_rewrite_loc_conf_t  *lcf = conf;
  
      ngx_int_t                            index;
      ngx_str_t                           *value;
      ngx_http_variable_t                 *v;
      ngx_http_script_var_code_t          *vcode;
      ngx_http_script_var_handler_code_t  *vhcode;
  
      value = cf->args->elts;
  
      if (value[1].data[0] != '$') {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "invalid variable name \"%V\"", &value[1]);
          return NGX_CONF_ERROR;
      }
  
      value[1].len--;
      value[1].data++;
  
      v = ngx_http_add_variable(cf, &value[1], NGX_HTTP_VAR_CHANGEABLE);
      if (v == NULL) {
          return NGX_CONF_ERROR;
      }
  
      index = ngx_http_get_variable_index(cf, &value[1]);
      if (index == NGX_ERROR) {
          return NGX_CONF_ERROR;
      }
  
      if (v->get_handler == NULL
          && ngx_strncasecmp(value[1].data, (u_char *) "http_", 5) != 0
          && ngx_strncasecmp(value[1].data, (u_char *) "sent_http_", 10) != 0
          && ngx_strncasecmp(value[1].data, (u_char *) "upstream_http_", 14) != 0)
      {
          v->get_handler = ngx_http_rewrite_var;
          v->data = index;
      }
  
      if (ngx_http_rewrite_value(cf, lcf, &value[2]) != NGX_CONF_OK) {
          return NGX_CONF_ERROR;
      }
  
      if (v->set_handler) {
          vhcode = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                     sizeof(ngx_http_script_var_handler_code_t));
          if (vhcode == NULL) {
              return NGX_CONF_ERROR;
          }
  
          vhcode->code = ngx_http_script_var_set_handler_code;
          vhcode->handler = v->set_handler;
          vhcode->data = v->data;
  
          return NGX_CONF_OK;
      }
  
      vcode = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                         sizeof(ngx_http_script_var_code_t));
      if (vcode == NULL) {
          return NGX_CONF_ERROR;
      }
  
      vcode->code = ngx_http_script_set_var_code;
      vcode->index = (uintptr_t) index;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_rewrite_value(ngx_conf_t *cf, ngx_http_rewrite_loc_conf_t *lcf,
      ngx_str_t *value)
  {
      ngx_int_t                              n;
      ngx_http_script_compile_t              sc;
      ngx_http_script_value_code_t          *val;
      ngx_http_script_complex_value_code_t  *complex;
  
      n = ngx_http_script_variables_count(value);
  
      if (n == 0) {
          val = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                           sizeof(ngx_http_script_value_code_t));
          if (val == NULL) {
              return NGX_CONF_ERROR;
          }
  
          n = ngx_atoi(value->data, value->len);
  
          if (n == NGX_ERROR) {
              n = 0;
          }
  
          val->code = ngx_http_script_value_code;
          val->value = (uintptr_t) n;
          val->text_len = (uintptr_t) value->len;
          val->text_data = (uintptr_t) value->data;
  
          return NGX_CONF_OK;
      }
  
      complex = ngx_http_script_start_code(cf->pool, &lcf->codes,
                                   sizeof(ngx_http_script_complex_value_code_t));
      if (complex == NULL) {
          return NGX_CONF_ERROR;
      }
  
      complex->code = ngx_http_script_complex_value_code;
      complex->lengths = NULL;
  
      ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));
  
      sc.cf = cf;
      sc.source = value;
      sc.lengths = &complex->lengths;
      sc.values = &lcf->codes;
      sc.variables = n;
      sc.complete_lengths = 1;
  
      if (ngx_http_script_compile(&sc) != NGX_OK) {
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  