On September 10th, 2013, 12:07 p.m. UTC, Jan Safranek wrote:

Just one issue, otherwise the patch looks good to me.

On September 10th, 2013, 12:21 p.m. UTC, Robin Hack wrote:

Ok. This is real issue. Copying can be avoided by using g_quark_from_static_string () instead.

What I want is try to avoid hash collision because this is what i found in
glib source code:

 * Note that the hash functions provided by GLib have these qualities,
 * but are not particularly robust against manufactured keys that
 * cause hash collisions. Therefore, you should consider choosing
 * a more secure hash function when using a GHashTable with keys
 * that originate in untrusted data (such as HTTP requests).
 * Using g_str_hash() in that situation might make your application
 * vulerable to <ulink url="https://lwn.net/Articles/474912/">Algorithmic Complexity Attacks</ulink>.

I use quark to get unique string identifier and use them as key in hash table
where pointer to lock_t structure is stored.

Now i know, that i must/should use something which is quark but not quark from glib.
Because glib use hash lookup anyway.

quark_from_string (const gchar *string,
                   gboolean     duplicate)
...
quark = quark_new (duplicate ? quark_strdup (string) : (gchar *)string);
...

Missing part of code:
  if (quark_ht)
    quark = GPOINTER_TO_UINT (g_hash_table_lookup (quark_ht, string));

- Robin

On September 10th, 2013, 7:29 a.m. UTC, Robin Hack wrote:

Account: Added associative thread locking.