-/* Try to share an object against the shared objects pool */
-static robj *tryObjectSharing(robj *o) {
- struct dictEntry *de;
- unsigned long c;
-
- if (o == NULL || server.shareobjects == 0) return o;
-
- redisAssert(o->type == REDIS_STRING);
- de = dictFind(server.sharingpool,o);
- if (de) {
- robj *shared = dictGetEntryKey(de);
-
- c = ((unsigned long) dictGetEntryVal(de))+1;
- dictGetEntryVal(de) = (void*) c;
- incrRefCount(shared);
- decrRefCount(o);
- return shared;
- } else {
- /* Here we are using a stream algorihtm: Every time an object is
- * shared we increment its count, everytime there is a miss we
- * recrement the counter of a random object. If this object reaches
- * zero we remove the object and put the current object instead. */
- if (dictSize(server.sharingpool) >=
- server.sharingpoolsize) {
- de = dictGetRandomKey(server.sharingpool);
- redisAssert(de != NULL);
- c = ((unsigned long) dictGetEntryVal(de))-1;
- dictGetEntryVal(de) = (void*) c;
- if (c == 0) {
- dictDelete(server.sharingpool,de->key);
- }
- } else {
- c = 0; /* If the pool is empty we want to add this object */
- }
- if (c == 0) {
- int retval;
-
- retval = dictAdd(server.sharingpool,o,(void*)1);
- redisAssert(retval == DICT_OK);
- incrRefCount(o);
- }
- return o;
- }
-}
-