text: 
  /*
   * Copyright (C) Nginx, Inc.
   * Copyright (C) Valentin V. Bartenev
   */
  
  
  #include <ngx_config.h>
  #include <ngx_core.h>
  #include <ngx_http.h>
  #include <ngx_http_v2_module.h>
  
  
  static ngx_int_t ngx_http_v2_add_variables(ngx_conf_t *cf);
  
  static ngx_int_t ngx_http_v2_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data);
  
  static ngx_int_t ngx_http_v2_module_init(ngx_cycle_t *cycle);
  
  static void *ngx_http_v2_create_main_conf(ngx_conf_t *cf);
  static char *ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf);
  static void *ngx_http_v2_create_srv_conf(ngx_conf_t *cf);
  static char *ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent,
      void *child);
  static void *ngx_http_v2_create_loc_conf(ngx_conf_t *cf);
  static char *ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent,
      void *child);
  
  static char *ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post,
      void *data);
  static char *ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data);
  static char *ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data);
  static char *ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post,
      void *data);
  static char *ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data);
  static char *ngx_http_v2_spdy_deprecated(ngx_conf_t *cf, ngx_command_t *cmd,
      void *conf);
  
  
  static ngx_conf_post_t  ngx_http_v2_recv_buffer_size_post =
      { ngx_http_v2_recv_buffer_size };
  static ngx_conf_post_t  ngx_http_v2_pool_size_post =
      { ngx_http_v2_pool_size };
  static ngx_conf_post_t  ngx_http_v2_preread_size_post =
      { ngx_http_v2_preread_size };
  static ngx_conf_post_t  ngx_http_v2_streams_index_mask_post =
      { ngx_http_v2_streams_index_mask };
  static ngx_conf_post_t  ngx_http_v2_chunk_size_post =
      { ngx_http_v2_chunk_size };
  
  
  static ngx_command_t  ngx_http_v2_commands[] = {
  
      { ngx_string("http2_recv_buffer_size"),
        NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_MAIN_CONF_OFFSET,
        offsetof(ngx_http_v2_main_conf_t, recv_buffer_size),
        &ngx_http_v2_recv_buffer_size_post },
  
      { ngx_string("http2_pool_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, pool_size),
        &ngx_http_v2_pool_size_post },
  
      { ngx_string("http2_max_concurrent_streams"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, concurrent_streams),
        NULL },
  
      { ngx_string("http2_max_field_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, max_field_size),
        NULL },
  
      { ngx_string("http2_max_header_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, max_header_size),
        NULL },
  
      { ngx_string("http2_body_preread_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, preread_size),
        &ngx_http_v2_preread_size_post },
  
      { ngx_string("http2_streams_index_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_num_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, streams_index_mask),
        &ngx_http_v2_streams_index_mask_post },
  
      { ngx_string("http2_recv_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, recv_timeout),
        NULL },
  
      { ngx_string("http2_idle_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_msec_slot,
        NGX_HTTP_SRV_CONF_OFFSET,
        offsetof(ngx_http_v2_srv_conf_t, idle_timeout),
        NULL },
  
      { ngx_string("http2_chunk_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_conf_set_size_slot,
        NGX_HTTP_LOC_CONF_OFFSET,
        offsetof(ngx_http_v2_loc_conf_t, chunk_size),
        &ngx_http_v2_chunk_size_post },
  
      { ngx_string("spdy_recv_buffer_size"),
        NGX_HTTP_MAIN_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_MAIN_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_pool_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_max_concurrent_streams"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_streams_index_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_recv_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_keepalive_timeout"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_headers_comp"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_SRV_CONF_OFFSET,
        0,
        NULL },
  
      { ngx_string("spdy_chunk_size"),
        NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
        ngx_http_v2_spdy_deprecated,
        NGX_HTTP_LOC_CONF_OFFSET,
        0,
        NULL },
  
        ngx_null_command
  };
  
  
  static ngx_http_module_t  ngx_http_v2_module_ctx = {
      ngx_http_v2_add_variables,             /* preconfiguration */
      NULL,                                  /* postconfiguration */
  
      ngx_http_v2_create_main_conf,          /* create main configuration */
      ngx_http_v2_init_main_conf,            /* init main configuration */
  
      ngx_http_v2_create_srv_conf,           /* create server configuration */
      ngx_http_v2_merge_srv_conf,            /* merge server configuration */
  
      ngx_http_v2_create_loc_conf,           /* create location configuration */
      ngx_http_v2_merge_loc_conf             /* merge location configuration */
  };
  
  
  ngx_module_t  ngx_http_v2_module = {
      NGX_MODULE_V1,
      &ngx_http_v2_module_ctx,               /* module context */
      ngx_http_v2_commands,                  /* module directives */
      NGX_HTTP_MODULE,                       /* module type */
      NULL,                                  /* init master */
      ngx_http_v2_module_init,               /* init module */
      NULL,                                  /* init process */
      NULL,                                  /* init thread */
      NULL,                                  /* exit thread */
      NULL,                                  /* exit process */
      NULL,                                  /* exit master */
      NGX_MODULE_V1_PADDING
  };
  
  
  static ngx_http_variable_t  ngx_http_v2_vars[] = {
  
      { ngx_string("http2"), NULL,
        ngx_http_v2_variable, 0, 0, 0 },
  
      { ngx_null_string, NULL, NULL, 0, 0, 0 }
  };
  
  
  static ngx_int_t
  ngx_http_v2_add_variables(ngx_conf_t *cf)
  {
      ngx_http_variable_t  *var, *v;
  
      for (v = ngx_http_v2_vars; v->name.len; v++) {
          var = ngx_http_add_variable(cf, &v->name, v->flags);
          if (var == NULL) {
              return NGX_ERROR;
          }
  
          var->get_handler = v->get_handler;
          var->data = v->data;
      }
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_v2_variable(ngx_http_request_t *r,
      ngx_http_variable_value_t *v, uintptr_t data)
  {
  
      if (r->stream) {
  #if (NGX_HTTP_SSL)
  
          if (r->connection->ssl) {
              v->len = sizeof("h2") - 1;
              v->valid = 1;
              v->no_cacheable = 0;
              v->not_found = 0;
              v->data = (u_char *) "h2";
  
              return NGX_OK;
          }
  
  #endif
          v->len = sizeof("h2c") - 1;
          v->valid = 1;
          v->no_cacheable = 0;
          v->not_found = 0;
          v->data = (u_char *) "h2c";
  
          return NGX_OK;
      }
  
      *v = ngx_http_variable_null_value;
  
      return NGX_OK;
  }
  
  
  static ngx_int_t
  ngx_http_v2_module_init(ngx_cycle_t *cycle)
  {
      return NGX_OK;
  }
  
  
  static void *
  ngx_http_v2_create_main_conf(ngx_conf_t *cf)
  {
      ngx_http_v2_main_conf_t  *h2mcf;
  
      h2mcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_main_conf_t));
      if (h2mcf == NULL) {
          return NULL;
      }
  
      h2mcf->recv_buffer_size = NGX_CONF_UNSET_SIZE;
  
      return h2mcf;
  }
  
  
  static char *
  ngx_http_v2_init_main_conf(ngx_conf_t *cf, void *conf)
  {
      ngx_http_v2_main_conf_t *h2mcf = conf;
  
      ngx_conf_init_size_value(h2mcf->recv_buffer_size, 256 * 1024);
  
      return NGX_CONF_OK;
  }
  
  
  static void *
  ngx_http_v2_create_srv_conf(ngx_conf_t *cf)
  {
      ngx_http_v2_srv_conf_t  *h2scf;
  
      h2scf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_srv_conf_t));
      if (h2scf == NULL) {
          return NULL;
      }
  
      h2scf->pool_size = NGX_CONF_UNSET_SIZE;
  
      h2scf->concurrent_streams = NGX_CONF_UNSET_UINT;
  
      h2scf->max_field_size = NGX_CONF_UNSET_SIZE;
      h2scf->max_header_size = NGX_CONF_UNSET_SIZE;
  
      h2scf->preread_size = NGX_CONF_UNSET_SIZE;
  
      h2scf->streams_index_mask = NGX_CONF_UNSET_UINT;
  
      h2scf->recv_timeout = NGX_CONF_UNSET_MSEC;
      h2scf->idle_timeout = NGX_CONF_UNSET_MSEC;
  
      return h2scf;
  }
  
  
  static char *
  ngx_http_v2_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child)
  {
      ngx_http_v2_srv_conf_t *prev = parent;
      ngx_http_v2_srv_conf_t *conf = child;
  
      ngx_conf_merge_size_value(conf->pool_size, prev->pool_size, 4096);
  
      ngx_conf_merge_uint_value(conf->concurrent_streams,
                                prev->concurrent_streams, 128);
  
      ngx_conf_merge_size_value(conf->max_field_size, prev->max_field_size,
                                4096);
      ngx_conf_merge_size_value(conf->max_header_size, prev->max_header_size,
                                16384);
  
      ngx_conf_merge_size_value(conf->preread_size, prev->preread_size, 65536);
  
      ngx_conf_merge_uint_value(conf->streams_index_mask,
                                prev->streams_index_mask, 32 - 1);
  
      ngx_conf_merge_msec_value(conf->recv_timeout,
                                prev->recv_timeout, 30000);
      ngx_conf_merge_msec_value(conf->idle_timeout,
                                prev->idle_timeout, 180000);
  
      return NGX_CONF_OK;
  }
  
  
  static void *
  ngx_http_v2_create_loc_conf(ngx_conf_t *cf)
  {
      ngx_http_v2_loc_conf_t  *h2lcf;
  
      h2lcf = ngx_pcalloc(cf->pool, sizeof(ngx_http_v2_loc_conf_t));
      if (h2lcf == NULL) {
          return NULL;
      }
  
      h2lcf->chunk_size = NGX_CONF_UNSET_SIZE;
  
      return h2lcf;
  }
  
  
  static char *
  ngx_http_v2_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
  {
      ngx_http_v2_loc_conf_t *prev = parent;
      ngx_http_v2_loc_conf_t *conf = child;
  
      ngx_conf_merge_size_value(conf->chunk_size, prev->chunk_size, 8 * 1024);
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_recv_buffer_size(ngx_conf_t *cf, void *post, void *data)
  {
      size_t *sp = data;
  
      if (*sp <= 2 * NGX_HTTP_V2_STATE_BUFFER_SIZE) {
          return "value is too small";
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_pool_size(ngx_conf_t *cf, void *post, void *data)
  {
      size_t *sp = data;
  
      if (*sp < NGX_MIN_POOL_SIZE) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "the pool size must be no less than %uz",
                             NGX_MIN_POOL_SIZE);
  
          return NGX_CONF_ERROR;
      }
  
      if (*sp % NGX_POOL_ALIGNMENT) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "the pool size must be a multiple of %uz",
                             NGX_POOL_ALIGNMENT);
  
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_preread_size(ngx_conf_t *cf, void *post, void *data)
  {
      size_t *sp = data;
  
      if (*sp > NGX_HTTP_V2_MAX_WINDOW) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "the maximum body preread buffer size is %uz",
                             NGX_HTTP_V2_MAX_WINDOW);
  
          return NGX_CONF_ERROR;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_streams_index_mask(ngx_conf_t *cf, void *post, void *data)
  {
      ngx_uint_t *np = data;
  
      ngx_uint_t  mask;
  
      mask = *np - 1;
  
      if (*np == 0 || (*np & mask)) {
          return "must be a power of two";
      }
  
      *np = mask;
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_chunk_size(ngx_conf_t *cf, void *post, void *data)
  {
      size_t *sp = data;
  
      if (*sp == 0) {
          ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                             "the http2 chunk size cannot be zero");
  
          return NGX_CONF_ERROR;
      }
  
      if (*sp > NGX_HTTP_V2_MAX_FRAME_SIZE) {
          *sp = NGX_HTTP_V2_MAX_FRAME_SIZE;
      }
  
      return NGX_CONF_OK;
  }
  
  
  static char *
  ngx_http_v2_spdy_deprecated(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
  {
      ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
                         "invalid directive \"%V\": ngx_http_spdy_module "
                         "was superseded by ngx_http_v2_module", &cmd->name);
  
      return NGX_CONF_OK;
  }
  