Merging r4147, r4148, r4149, r4150, r4207: Fixes of combination of error_page and return directives: *) Fix for incorrect 201 replies from dav module. Replies with 201 code contain body, and we should clearly indicate it's empty if it's empty. Before 0.8.32 chunked was explicitly disabled for 201 replies and as a result empty body was indicated by connection close (not perfect, but worked). Since 0.8.32 chunked is enabled, and this causes incorrect responses from dav module when HTTP/1.1 is used: with "Transfer-Encoding: chunked" but no chunks at all. Fix is to actually return empty body in special response handler instead of abusing r->header_only flag. See here for initial report: http://mailman.nginx.org/pipermail/nginx-ru/2010-October/037535.html *) 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. *) Fix for "return 202" not discarding body. Big POST (not fully preread) to a location / { return 202; } resulted in incorrect behaviour due to "return" code path not calling ngx_http_discard_request_body(). The same applies to all "return" used with 2xx/3xx codes except 201 and 204, and to all "return ... text" uses. Fix is to add ngx_http_discard_request_body() call to ngx_http_send_response() function where it looks appropriate. Discard body call from emtpy gif module removed as it's now redundant. Reported by Pyry Hakulinen, see http://mailman.nginx.org/pipermail/nginx/2011-August/028503.html *) Incorrect special case for "return 204" removed. The special case in question leads to replies without body in configuration like location / { error_page 404 /zero; return 404; } location /zero { return 204; } while replies with empty body are expected per protocol specs. Correct one will look like if (status == NGX_HTTP_NO_CONTENT) { rc = ngx_http_send_header(r); if (rc == NGX_ERROR || r->header_only) { return rc; } return ngx_http_send_special(r, NGX_HTTP_LAST); } though it looks like it's better to drop this special case at all. *) Clear old Location header (if any) while adding a new one. This prevents incorrect behaviour when another redirect is issued within error_page 302 handler.

/*
 * Copyright (C) Igor Sysoev
 */


#ifndef _NGX_HTTP_UPSTREAM_ROUND_ROBIN_H_INCLUDED_
#define _NGX_HTTP_UPSTREAM_ROUND_ROBIN_H_INCLUDED_


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


typedef struct {
    struct sockaddr                *sockaddr;
    socklen_t                       socklen;
    ngx_str_t                       name;

    ngx_int_t                       current_weight;
    ngx_int_t                       weight;

    ngx_uint_t                      fails;
    time_t                          accessed;

    ngx_uint_t                      max_fails;
    time_t                          fail_timeout;

    ngx_uint_t                      down;          /* unsigned  down:1; */

#if (NGX_HTTP_SSL)
    ngx_ssl_session_t              *ssl_session;   /* local to a process */
#endif
} ngx_http_upstream_rr_peer_t;


typedef struct ngx_http_upstream_rr_peers_s  ngx_http_upstream_rr_peers_t;

struct ngx_http_upstream_rr_peers_s {
    ngx_uint_t                      single;        /* unsigned  single:1; */
    ngx_uint_t                      number;
    ngx_uint_t                      last_cached;

 /* ngx_mutex_t                    *mutex; */
    ngx_connection_t              **cached;

    ngx_str_t                      *name;

    ngx_http_upstream_rr_peers_t   *next;

    ngx_http_upstream_rr_peer_t     peer[1];
};


typedef struct {
    ngx_http_upstream_rr_peers_t   *peers;
    ngx_uint_t                      current;
    uintptr_t                      *tried;
    uintptr_t                       data;
} ngx_http_upstream_rr_peer_data_t;


ngx_int_t ngx_http_upstream_init_round_robin(ngx_conf_t *cf,
    ngx_http_upstream_srv_conf_t *us);
ngx_int_t ngx_http_upstream_init_round_robin_peer(ngx_http_request_t *r,
    ngx_http_upstream_srv_conf_t *us);
ngx_int_t ngx_http_upstream_create_round_robin_peer(ngx_http_request_t *r,
    ngx_http_upstream_resolved_t *ur);
ngx_int_t ngx_http_upstream_get_round_robin_peer(ngx_peer_connection_t *pc,
    void *data);
void ngx_http_upstream_free_round_robin_peer(ngx_peer_connection_t *pc,
    void *data, ngx_uint_t state);

#if (NGX_HTTP_SSL)
ngx_int_t
    ngx_http_upstream_set_round_robin_peer_session(ngx_peer_connection_t *pc,
    void *data);
void ngx_http_upstream_save_round_robin_peer_session(ngx_peer_connection_t *pc,
    void *data);
#endif


#endif /* _NGX_HTTP_UPSTREAM_ROUND_ROBIN_H_INCLUDED_ */