[cache] After writing cache to file, update the internal copy to reflect this

Only do it for small caches though.  For large cache we'd better off loading
the cache file again, mmap()ing it.

Based on patch from Diego Santa Cruz.

diff --git a/src/fccache.c b/src/fccache.c
index f35304a40cde1636a5b6d785c13593e13df227a6..ba28ddc6ab3ca14f96d4660b75da3cb4c4bda9bf 100644 (file)
--- a/src/fccache.c
+++ b/src/fccache.c
@@ -844,6 +844,8 @@ FcDirCacheWrite (FcCache *cache, FcConfig *config)
     FcStrList      *list;
     FcChar8        *cache_dir = NULL;
     FcChar8        *test_dir;
+    FcCacheSkip     *skip;
+    struct stat     cache_stat;
     int                    magic;
     int                    written;
 
@@ -929,6 +931,20 @@ FcDirCacheWrite (FcCache *cache, FcConfig *config)
     close(fd);
     if (!FcAtomicReplaceOrig(atomic))
         goto bail4;
+
+    /* If the file is small, update the cache chain entry such that the
+     * new cache file is not read again.  If it's large, we don't do that
+     * such that we reload it, using mmap, which is shared across processes.
+     */
+    if (cache->size < FC_CACHE_MIN_MMAP &&
+       (skip = FcCacheFindByAddr (cache)) &&
+       FcStat (cache_hashed, &cache_stat))
+    {
+       skip->cache_dev = cache_stat.st_dev;
+       skip->cache_ino = cache_stat.st_ino;
+       skip->cache_mtime = cache_stat.st_mtime;
+    }
+
     FcStrFree (cache_hashed);
     FcAtomicUnlock (atomic);
     FcAtomicDestroy (atomic);