release/src/router/nginx/src/http/ngx_http_postpone_filter_module.c

   1
   2 /*
   3  * Copyright (C) Igor Sysoev
   4  * Copyright (C) Nginx, Inc.
   5  */
   6
   7
   8 #include <ngx_config.h>
   9 #include <ngx_core.h>
  10 #include <ngx_http.h>
  11
  12
  13 static ngx_int_t ngx_http_postpone_filter_add(ngx_http_request_t *r,
  14     ngx_chain_t *in);
  15 static ngx_int_t ngx_http_postpone_filter_init(ngx_conf_t *cf);
  16
  17
  18 static ngx_http_module_t  ngx_http_postpone_filter_module_ctx = {
  19     NULL,                                  /* preconfiguration */
  20     ngx_http_postpone_filter_init,         /* postconfiguration */
  21
  22     NULL,                                  /* create main configuration */
  23     NULL,                                  /* init main configuration */
  24
  25     NULL,                                  /* create server configuration */
  26     NULL,                                  /* merge server configuration */
  27
  28     NULL,                                  /* create location configuration */
  29     NULL                                   /* merge location configuration */
  30 };
  31
  32
  33 ngx_module_t  ngx_http_postpone_filter_module = {
  34     NGX_MODULE_V1,
  35     &ngx_http_postpone_filter_module_ctx,  /* module context */
  36     NULL,                                  /* module directives */
  37     NGX_HTTP_MODULE,                       /* module type */
  38     NULL,                                  /* init master */
  39     NULL,                                  /* init module */
  40     NULL,                                  /* init process */
  41     NULL,                                  /* init thread */
  42     NULL,                                  /* exit thread */
  43     NULL,                                  /* exit process */
  44     NULL,                                  /* exit master */
  45     NGX_MODULE_V1_PADDING
  46 };
  47
  48
  49 static ngx_http_output_body_filter_pt    ngx_http_next_body_filter;
  50
  51
  52 static ngx_int_t
  53 ngx_http_postpone_filter(ngx_http_request_t *r, ngx_chain_t *in)
  54 {
  55     ngx_connection_t              *c;
  56     ngx_http_postponed_request_t  *pr;
  57
  58     c = r->connection;
  59
  60     ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
  61                    "http postpone filter \"%V?%V\" %p", &r->uri, &r->args, in);
  62
  63     if (r != c->data) {
  64
  65         if (in) {
  66             ngx_http_postpone_filter_add(r, in);
  67             return NGX_OK;
  68         }
  69
  70 #if 0
  71         /* TODO: SSI may pass NULL */
  72         ngx_log_error(NGX_LOG_ALERT, c->log, 0,
  73                       "http postpone filter NULL inactive request",
  74                       &r->uri, &r->args);
  75 #endif
  76
  77         return NGX_OK;
  78     }
  79
  80     if (r->postponed == NULL) {
  81
  82         if (in || c->buffered) {
  83             return ngx_http_next_body_filter(r->main, in);
  84         }
  85
  86         return NGX_OK;
  87     }
  88
  89     if (in) {
  90         ngx_http_postpone_filter_add(r, in);
  91     }
  92
  93     do {
  94         pr = r->postponed;
  95
  96         if (pr->request) {
  97
  98             ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
  99                            "http postpone filter wake \"%V?%V\"",
 100                            &pr->request->uri, &pr->request->args);
 101
 102             r->postponed = pr->next;
 103
 104             c->data = pr->request;
 105
 106             return ngx_http_post_request(pr->request, NULL);
 107         }
 108
 109         if (pr->out == NULL) {
 110             ngx_log_error(NGX_LOG_ALERT, c->log, 0,
 111                           "http postpone filter NULL output",
 112                           &r->uri, &r->args);
 113
 114         } else {
 115             ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
 116                            "http postpone filter output \"%V?%V\"",
 117                            &r->uri, &r->args);
 118
 119             if (ngx_http_next_body_filter(r->main, pr->out) == NGX_ERROR) {
 120                 return NGX_ERROR;
 121             }
 122         }
 123
 124         r->postponed = pr->next;
 125
 126     } while (r->postponed);
 127
 128     return NGX_OK;
 129 }
 130
 131
 132 static ngx_int_t
 133 ngx_http_postpone_filter_add(ngx_http_request_t *r, ngx_chain_t *in)
 134 {
 135     ngx_http_postponed_request_t  *pr, **ppr;
 136
 137     if (r->postponed) {
 138         for (pr = r->postponed; pr->next; pr = pr->next) { /* void */ }
 139
 140         if (pr->request == NULL) {
 141             goto found;
 142         }
 143
 144         ppr = &pr->next;
 145
 146     } else {
 147         ppr = &r->postponed;
 148     }
 149
 150     pr = ngx_palloc(r->pool, sizeof(ngx_http_postponed_request_t));
 151     if (pr == NULL) {
 152         return NGX_ERROR;
 153     }
 154
 155     *ppr = pr;
 156
 157     pr->request = NULL;
 158     pr->out = NULL;
 159     pr->next = NULL;
 160
 161 found:
 162
 163     if (ngx_chain_add_copy(r->pool, &pr->out, in) == NGX_OK) {
 164         return NGX_OK;
 165     }
 166
 167     return NGX_ERROR;
 168 }
 169
 170
 171 static ngx_int_t
 172 ngx_http_postpone_filter_init(ngx_conf_t *cf)
 173 {
 174     ngx_http_next_body_filter = ngx_http_top_body_filter;
 175     ngx_http_top_body_filter = ngx_http_postpone_filter;
 176
 177     return NGX_OK;
 178 }