Fix rehashing memory leaks

The pattern to move a key for various types (strings, sets, zsets,
hashes, etc) used a simple pattern:

1.  Construct the call in order to get all of the keys from the source
2.  Make a pass through call to the source node to get a response
3.  Use the response to make a pass through call to the destination node

The issue, however, was that we were using the same return value variable
for both source and destination nodes, so we would leak the response from
the source node.

Author: michael-grunder

redis_array_impl.c

@@ -884,7 +884,7 @@ ra_expire_key(const char *key, int key_len, zval *z_to, long ttl TSRMLS_DC) {
 static zend_bool
 ra_move_zset(const char *key, int key_len, zval *z_from, zval *z_to, long ttl TSRMLS_DC) {
 
-	zval z_fun_zrange, z_fun_zadd, z_ret, *z_args[4], **z_zadd_args, **z_score_pp;
+	zval z_fun_zrange, z_fun_zadd, z_ret, z_ret_dest, *z_args[4], **z_zadd_args, **z_score_pp;
 	int count;
 	HashTable *h_zset_vals;
 	char *val;
@@ -953,7 +953,7 @@ ra_move_zset(const char *key, int key_len, zval *z_from, zval *z_to, long ttl TS
 	ZVAL_STRINGL(&z_fun_zadd, "ZADD", 4, 0);
 	MAKE_STD_ZVAL(z_zadd_args[0]);
 	ZVAL_STRINGL(z_zadd_args[0], key, key_len, 0);
-	call_user_function(&redis_ce->function_table, &z_to, &z_fun_zadd, &z_ret, 1 + 2 * count, z_zadd_args TSRMLS_CC);
+	call_user_function(&redis_ce->function_table, &z_to, &z_fun_zadd, &z_ret_dest, 1 + 2 * count, z_zadd_args TSRMLS_CC);
 
 	/* Expire if needed */
 	ra_expire_key(key, key_len, z_to, ttl TSRMLS_CC);
@@ -963,6 +963,8 @@ ra_move_zset(const char *key, int key_len, zval *z_from, zval *z_to, long ttl TS
 		efree(z_zadd_args[i]);
 	}
 
+    zval_dtor(&z_ret);
+
     /* Free the array itself */
     efree(z_zadd_args);
 
@@ -1021,7 +1023,7 @@ ra_move_string(const char *key, int key_len, zval *z_from, zval *z_to, long ttl
 static zend_bool
 ra_move_hash(const char *key, int key_len, zval *z_from, zval *z_to, long ttl TSRMLS_DC) {
 
-	zval z_fun_hgetall, z_fun_hmset, z_ret, *z_args[2];
+	zval z_fun_hgetall, z_fun_hmset, z_ret, z_ret_dest, *z_args[2];
 
 	/* run HGETALL on source */
 	MAKE_STD_ZVAL(z_args[0]);
@@ -1039,13 +1041,14 @@ ra_move_hash(const char *key, int key_len, zval *z_from, zval *z_to, long ttl TS
 	ZVAL_STRINGL(&z_fun_hmset, "HMSET", 5, 0);
 	ZVAL_STRINGL(z_args[0], key, key_len, 0);
 	z_args[1] = &z_ret; /* copy z_ret to arg 1 */
-	call_user_function(&redis_ce->function_table, &z_to, &z_fun_hmset, &z_ret, 2, z_args TSRMLS_CC);
+	call_user_function(&redis_ce->function_table, &z_to, &z_fun_hmset, &z_ret_dest, 2, z_args TSRMLS_CC);
 
 	/* Expire if needed */
 	ra_expire_key(key, key_len, z_to, ttl TSRMLS_CC);
 
 	/* cleanup */
 	efree(z_args[0]);
+    zval_dtor(&z_ret);
 
 	return 1;
 }
@@ -1107,7 +1110,11 @@ ra_move_collection(const char *key, int key_len, zval *z_from, zval *z_to,
 		*(z_sadd_args[i+1]) = **z_data_pp;
 		zval_copy_ctor(z_sadd_args[i+1]);
 	}
-	call_user_function(&redis_ce->function_table, &z_to, &z_fun_sadd, &z_ret, count+1, z_sadd_args TSRMLS_CC);
+
+    /* Clean up our input return value */
+    zval_dtor(&z_ret);
+
+    call_user_function(&redis_ce->function_table, &z_to, &z_fun_sadd, &z_ret, count+1, z_sadd_args TSRMLS_CC);
 
 	/* Expire if needed */
 	ra_expire_key(key, key_len, z_to, ttl TSRMLS_CC);
@@ -1121,6 +1128,9 @@ ra_move_collection(const char *key, int key_len, zval *z_from, zval *z_to,
 	}
 	efree(z_sadd_args);
 
+    /* Clean up our output return value */
+    zval_dtor(&z_ret);
+
 	return 1;
 }