Add head comment to shared.c

[cgit.git] / cache.c

diff --git a/cache.c b/cache.c
index 0ffa502c119ae33deaac913eabb742679cf4fe18..39e63a52bc6e488ef20a988b83f28bcf5a0c2db1 100644 (file)
--- a/cache.c
+++ b/cache.c
@@ -61,26 +61,36 @@ int cache_create_dirs()
        return 1;
 }
 
+int cache_refill_overdue(const char *lockfile)
+{
+       struct stat st;
+
+       if (stat(lockfile, &st))
+               return 0;
+       else
+               return (time(NULL) - st.st_mtime > cgit_cache_max_create_time);
+}
+
 int cache_lock(struct cacheitem *item)
 {
-       int ret;
-       char *lockfile = fmt("%s.lock", item->name);
+       int i = 0;
+       char *lockfile = xstrdup(fmt("%s.lock", item->name));
+
+ top:
+       if (++i > cgit_max_lock_attempts)
+               die("cache_lock: unable to lock %s: %s",
+                   item->name, strerror(errno));
+
+               item->fd = open(lockfile, O_WRONLY|O_CREAT|O_EXCL, S_IRUSR|S_IWUSR);
 
- top:  
-               item->fd = open(lockfile, O_WRONLY | O_CREAT | O_EXCL, S_IRUSR|S_IWUSR);
        if (item->fd == NOLOCK && errno == ENOENT && cache_create_dirs())
                goto top;
-       if (item->fd == NOLOCK && errno == EEXIST) {
-               struct stat st;
-               time_t t;
-               if (stat(lockfile, &st))
-                       return ret;
-               t = time(NULL);
-               if (t-st.st_mtime > cgit_cache_max_create_time && 
-                   !unlink(lockfile))
+
+       if (item->fd == NOLOCK && errno == EEXIST &&
+           cache_refill_overdue(lockfile) && !unlink(lockfile))
                        goto top;
-               return 0;
-       }
+
+       free(lockfile);
        return (item->fd > 0);
 }
 
@@ -90,6 +100,11 @@ int cache_unlock(struct cacheitem *item)
        return (rename(fmt("%s.lock", item->name), item->name) == 0);
 }
 
+int cache_cancel_lock(struct cacheitem *item)
+{
+       return (unlink(fmt("%s.lock", item->name)) == 0);
+}
+
 int cache_expired(struct cacheitem *item)
 {
        if (item->ttl < 0)