Lighttpd

I use lighttpd to serve an average of about 300mb/s of traffic across 30servers. They all serve images to users, and I have been noticing a serious memory leak while using 1.5.x. After running things in valgrind for a while, I determined that the leaked memory was being allocated from:

line 324 of stat_cache.c:
g_hash_table_insert(sc->files, buffer_init_string(BUF_STR(sc->hash_key)), sce);

The buffer_init_string() call will allocate a new buffer, but in the error conditions below it in lines 373 to 383 can return without freeing the memory allocated on line 324. This memory will not cleaned up in the standard stat_cache_trigger_cleanup() path because in this error case the state of the stat cache entry is never changed from STAT_CACHE_ENTRY_UNSET.

In order to fix this, I had to stash a pointer to this buffer in the stat cache entry itself, and in those error conditions, free the memory, the stat cache entry, and remove the entry from the stat cache's g_hash_table. Valgrind confirms the fix worked.

An easy way to reproduce this is to serve a lot of 404's in order to hit the error conditions described above.

I'm not sure if this is related at all to #1667, but it appears like it could be the issue in #1363.

-- gc3