view src/http/ngx_http_postpone_filter_module.c @ 4147:7f64de1cc2c0

Fix for double content when return is used in error_page handler. Test case: location / { error_page 405 /nope; return 405; } location /nope { return 200; } This is expected to return 405 with empty body, but in 0.8.42+ will return builtin 405 error page as well (though not counted in Content-Length, thus breaking protocol). Fix is to use status provided by rewrite script execution in case it's less than NGX_HTTP_BAD_REQUEST even if r->error_status set. This check is in line with one in ngx_http_script_return_code(). Note that this patch also changes behaviour for "return 302 ..." and "rewrite ... redirect" used as error handler. E.g. location / { error_page 405 /redirect; return 405; } location /redirect { rewrite ^ http://example.com/; } will actually return redirect to "http://example.com/" instead of builtin 405 error page with meaningless Location header. This looks like correct change and it's in line with what happens on e.g. directory redirects in error handlers.
author Maxim Dounin <mdounin@mdounin.ru>
date Tue, 27 Sep 2011 11:11:30 +0000
parents 23e6f26fb4bd
children d620f497c50f
line wrap: on
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/*
 * Copyright (C) Igor Sysoev
 */


#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>


static ngx_int_t ngx_http_postpone_filter_add(ngx_http_request_t *r,
    ngx_chain_t *in);
static ngx_int_t ngx_http_postpone_filter_init(ngx_conf_t *cf);


static ngx_http_module_t  ngx_http_postpone_filter_module_ctx = {
    NULL,                                  /* preconfiguration */
    ngx_http_postpone_filter_init,         /* postconfiguration */

    NULL,                                  /* create main configuration */
    NULL,                                  /* init main configuration */

    NULL,                                  /* create server configuration */
    NULL,                                  /* merge server configuration */

    NULL,                                  /* create location configuration */
    NULL                                   /* merge location configuration */
};


ngx_module_t  ngx_http_postpone_filter_module = {
    NGX_MODULE_V1,
    &ngx_http_postpone_filter_module_ctx,  /* module context */
    NULL,                                  /* 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_http_output_body_filter_pt    ngx_http_next_filter;


static ngx_int_t
ngx_http_postpone_filter(ngx_http_request_t *r, ngx_chain_t *in)
{
    ngx_connection_t              *c;
    ngx_http_postponed_request_t  *pr;

    c = r->connection;

    ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
                   "http postpone filter \"%V?%V\" %p", &r->uri, &r->args, in);

    if (r != c->data) {

        if (in) {
            ngx_http_postpone_filter_add(r, in);
            return NGX_OK;
        }

#if 0
        /* TODO: SSI may pass NULL */
        ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                      "http postpone filter NULL inactive request",
                      &r->uri, &r->args);
#endif

        return NGX_OK;
    }

    if (r->postponed == NULL) {

        if (in || c->buffered) {
            return ngx_http_next_filter(r->main, in);
        }

        return NGX_OK;
    }

    if (in) {
        ngx_http_postpone_filter_add(r, in);
    }

    do {
        pr = r->postponed;

        if (pr->request) {

            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http postpone filter wake \"%V?%V\"",
                           &pr->request->uri, &pr->request->args);

            r->postponed = pr->next;

            c->data = pr->request;

            return ngx_http_post_request(pr->request, NULL);
        }

        if (pr->out == NULL) {
            ngx_log_error(NGX_LOG_ALERT, c->log, 0,
                          "http postpone filter NULL output",
                          &r->uri, &r->args);

        } else {
            ngx_log_debug2(NGX_LOG_DEBUG_HTTP, c->log, 0,
                           "http postpone filter output \"%V?%V\"",
                           &r->uri, &r->args);

            if (ngx_http_next_filter(r->main, pr->out) == NGX_ERROR) {
                return NGX_ERROR;
            }
        }

        r->postponed = pr->next;

    } while (r->postponed);

    return NGX_OK;
}


static ngx_int_t
ngx_http_postpone_filter_add(ngx_http_request_t *r, ngx_chain_t *in)
{
    ngx_http_postponed_request_t  *pr, **ppr;

    if (r->postponed) {
        for (pr = r->postponed; pr->next; pr = pr->next) { /* void */ }

        if (pr->request == NULL) {
            goto found;
        }

        ppr = &pr->next;

    } else {
        ppr = &r->postponed;
    }

    pr = ngx_palloc(r->pool, sizeof(ngx_http_postponed_request_t));
    if (pr == NULL) {
        return NGX_ERROR;
    }

    *ppr = pr;

    pr->request = NULL;
    pr->out = NULL;
    pr->next = NULL;

found:

    if (ngx_chain_add_copy(r->pool, &pr->out, in) == NGX_OK) {
        return NGX_OK;
    }

    return NGX_ERROR;
}


static ngx_int_t
ngx_http_postpone_filter_init(ngx_conf_t *cf)
{
    ngx_http_next_filter = ngx_http_top_body_filter;
    ngx_http_top_body_filter = ngx_http_postpone_filter;

    return NGX_OK;
}