Merge of r3964, r3977, r3978:

Proxy related fixes:

*) finalizing with rc == 0 in unbuffered proxy mode caused nginx to wait
   for another send_timeout before actually closing client's connection
   if client timed out while still talking to upstream server
*) update r3945 with more descriptive error message
*) test length of proxy_pass with variables;
   patch by Lanshun Zhou

src/http/modules/ngx_http_fastcgi_module.c

@@ -2003,6 +2003,8 @@ ngx_http_fastcgi_create_loc_conf(ngx_conf_t *cf)
 
     conf->catch_stderr = NGX_CONF_UNSET_PTR;
 
+    ngx_str_set(&conf->upstream.module, "fastcgi");
+
     return conf;
 }
 

src/http/modules/ngx_http_proxy_module.c

@@ -642,15 +642,17 @@ ngx_http_proxy_eval(ngx_http_request_t *r, ngx_http_proxy_ctx_t *ctx,
         return NGX_ERROR;
     }
 
-    if (ngx_strncasecmp(proxy.data, (u_char *) "http://", 7) == 0) {
-
+    if (proxy.len > 7
+        && ngx_strncasecmp(proxy.data, (u_char *) "http://", 7) == 0)
+    {
         add = 7;
         port = 80;
 
 #if (NGX_HTTP_SSL)
 
-    } else if (ngx_strncasecmp(proxy.data, (u_char *) "https://", 8) == 0) {
-
+    } else if (proxy.len > 8
+               && ngx_strncasecmp(proxy.data, (u_char *) "https://", 8) == 0)
+    {
         add = 8;
         port = 443;
         r->upstream->ssl = 1;
@@ -1707,6 +1709,8 @@ ngx_http_proxy_create_loc_conf(ngx_conf_t *cf)
     conf->headers_hash_max_size = NGX_CONF_UNSET_UINT;
     conf->headers_hash_bucket_size = NGX_CONF_UNSET_UINT;
 
+    ngx_str_set(&conf->upstream.module, "proxy");
+
     return conf;
 }
 

src/http/modules/ngx_http_scgi_module.c

@@ -1030,6 +1030,8 @@ ngx_http_scgi_create_loc_conf(ngx_conf_t *cf)
     /* "scgi_cyclic_temp_file" is disabled */
     conf->upstream.cyclic_temp_file = 0;
 
+    ngx_str_set(&conf->upstream.module, "scgi");
+
     return conf;
 }
 

src/http/modules/ngx_http_uwsgi_module.c

@@ -1083,6 +1083,8 @@ ngx_http_uwsgi_create_loc_conf(ngx_conf_t *cf)
     /* "uwsgi_cyclic_temp_file" is disabled */
     conf->upstream.cyclic_temp_file = 0;
 
+    ngx_str_set(&conf->upstream.module, "uwsgi");
+
     return conf;
 }
 

src/http/ngx_http_upstream.c

@@ -661,10 +661,12 @@ ngx_http_upstream_cache(ngx_http_request_t *r, ngx_http_upstream_t *u)
 
         ngx_http_file_cache_create_key(r);
 
-        if (r->cache->header_start >= u->conf->buffer_size) {
+        if (r->cache->header_start + 256 >= u->conf->buffer_size) {
             ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                "cache key too large, increase upstream buffer size %uz",
-                u->conf->buffer_size);
+                          "%V_buffer_size %uz is not enough for cache key, "
+                          "it should increased at least to %uz",
+                          &u->conf->module, u->conf->buffer_size,
+                          ngx_align(r->cache->header_start + 256, 1024));
 
             r->cache = NULL;
             return NGX_DECLINED;
@@ -2317,7 +2319,7 @@ ngx_http_upstream_process_non_buffered_downstream(ngx_http_request_t *r)
     if (wev->timedout) {
         c->timedout = 1;
         ngx_connection_error(c, NGX_ETIMEDOUT, "client timed out");
-        ngx_http_upstream_finalize_request(r, u, 0);
+        ngx_http_upstream_finalize_request(r, u, NGX_HTTP_REQUEST_TIME_OUT);
         return;
     }
 
@@ -3013,6 +3015,7 @@ ngx_http_upstream_finalize_request(ngx_http_request_t *r,
 #endif
 
     if (u->header_sent
+        && rc != NGX_HTTP_REQUEST_TIME_OUT
         && (rc == NGX_ERROR || rc >= NGX_HTTP_SPECIAL_RESPONSE))
     {
         rc = 0;

src/http/ngx_http_upstream.h

@@ -179,6 +179,7 @@ typedef struct {
     ngx_flag_t                       ssl_session_reuse;
 #endif
 
+    ngx_str_t                        module;
 } ngx_http_upstream_conf_t;