From f5069d88dff7a7ed2f4665904b03e906cca75a7c Mon Sep 17 00:00:00 2001 From: Lars Hjemli Date: Mon, 11 Dec 2006 09:57:58 +0100 Subject: Fix cache algorithm loophole This closes the door for unneccessary calls to cgit_fill_cache(). Noticed by Linus. Signed-off-by: Lars Hjemli --- cache.c | 6 +++++- cgit.c | 18 +++++++++--------- cgit.h | 3 ++- 3 files changed, 16 insertions(+), 11 deletions(-) diff --git a/cache.c b/cache.c index b034c48..0ffa502 100644 --- a/cache.c +++ b/cache.c @@ -10,7 +10,7 @@ const int NOLOCK = -1; -int cache_lookup(struct cacheitem *item) +void cache_prepare(struct cacheitem *item) { if (!cgit_query_repo) { item->name = xstrdup(fmt("%s/index.html", cgit_cache_root)); @@ -30,6 +30,10 @@ int cache_lookup(struct cacheitem *item) else item->ttl = cgit_cache_repo_ttl; } +} + +int cache_exist(struct cacheitem *item) +{ if (stat(item->name, &item->st)) { item->st.st_mtime = 0; return 0; diff --git a/cgit.c b/cgit.c index 110face..7f14016 100644 --- a/cgit.c +++ b/cgit.c @@ -465,20 +465,20 @@ static void cgit_fill_cache(struct cacheitem *item) static void cgit_refresh_cache(struct cacheitem *item) { + cache_prepare(item); top: - if (!cache_lookup(item)) { - if (cache_lock(item)) { - cgit_fill_cache(item); - cache_unlock(item); - } else { + if (!cache_exist(item)) { + if (!cache_lock(item)) { sched_yield(); goto top; } - } else if (cache_expired(item)) { - if (cache_lock(item)) { + if (!cache_exist(item)) cgit_fill_cache(item); - cache_unlock(item); - } + cache_unlock(item); + } else if (cache_expired(item) && cache_lock(item)) { + if (cache_expired(item)) + cgit_fill_cache(item); + cache_unlock(item); } } diff --git a/cgit.h b/cgit.h index 1e084d4..3b0994a 100644 --- a/cgit.h +++ b/cgit.h @@ -56,9 +56,10 @@ extern void html_link_close(void); extern int cgit_read_config(const char *filename, configfn fn); -extern int cache_lookup(struct cacheitem *item); +extern void cache_prepare(struct cacheitem *item); extern int cache_lock(struct cacheitem *item); extern int cache_unlock(struct cacheitem *item); +extern int cache_exist(struct cacheitem *item); extern int cache_expired(struct cacheitem *item); #endif /* CGIT_H */ -- cgit v1.2.3-57-g22cb