[PATCH 12 of 15] Tempfiles: Expired tempfiles

[Jiří Setnička]

# HG changeset patch
# User Jiří Setnička  <jiri.setnicka at cdn77.com>
# Date 1643385660 -3600
#      Fri Jan 28 17:01:00 2022 +0100
# Node ID 0e00ffe7fab3dcf3d3167851237327e5fb9e10b6
# Parent  64a2e216aeeeb847eb0b9a83ed6e6082ade4ac9e
Tempfiles: Expired tempfiles
When tempfile expires before it is downloaded we try to fire one
request to download newer version of the tempfile and remain other
requests locked.

diff --git a/src/http/ngx_http_file_cache.c b/src/http/ngx_http_file_cache.c
--- a/src/http/ngx_http_file_cache.c
+++ b/src/http/ngx_http_file_cache.c
@@ -939,10 +939,15 @@ ngx_http_file_cache_read(ngx_http_reques
 
         ngx_shmtx_lock(&cache->shpool->mutex);
 
-        if (c->node->updating) {
+        /* If serving tempfile and it is already expired try to download a new
+         * one (but only if not downloading it already) */
+        if (c->node->updating
+            && (!c->tf_node || c->node->tf_number != c->tf_node->node.key)
+        ) {
             rc = NGX_HTTP_CACHE_UPDATING;
 
         } else {
+            c->node->tf_number = 0;
             c->node->updating = 1;
             c->updating = 1;
             c->node->lock_time = ngx_current_msec + (c->lock ? c->lock_age : c->tempfile_timeout);
@@ -1791,8 +1796,10 @@ ngx_http_file_cache_update(ngx_http_requ
         ngx_http_file_cache_tf_delete(c, cache);
     }
 
-    c->node->updating = 0;
-    c->node->tf_number = 0;
+    if (c->node->lock_time == c->lock_time) {
+        c->node->updating = 0;
+        c->node->tf_number = 0;
+    }
 
     ngx_shmtx_unlock(&cache->shpool->mutex);
 }