Ensure we don't try and send 0 expires for SET

As raised by issues phpredis#579, and phpredis#640 phpredis could be made to silently
revert to a "SET" call (no expiry) if a non long argument was specified
for EX or PX options, as well as an invalid base timeout value.

This modification changes the code so we don't even send the command to
Redis in such cases, which also avoids a round trip.

Author: michael-grunder

redis_commands.c

@@ -1008,7 +1008,7 @@ int redis_key_arr_cmd(INTERNAL_FUNCTION_PARAMETERS, RedisSock *redis_sock,
                       char *kw, char **cmd, int *cmd_len, short *slot,
                       void **ctx)
 {
-    zval *z_key, *z_arr, **z_val;
+    zval *z_arr, **z_val;
     HashTable *ht_arr;
     HashPosition pos;
     smart_str cmdstr = {0};
@@ -1225,23 +1225,31 @@ int redis_set_cmd(INTERNAL_FUNCTION_PARAMETERS, RedisSock *redis_sock,
             zend_hash_move_forward(kt))
         {
             // Grab key and value
-            type = zend_hash_get_current_key_ex(kt, &k, &ht_key_len, &idx, 0,
-                                                NULL);
+            type = zend_hash_get_current_key_ex(kt, &k, &ht_key_len, &idx, 0, NULL);
             zend_hash_get_current_data(kt, (void**)&v);
 
-            if(type == HASH_KEY_IS_STRING && (Z_TYPE_PP(v) == IS_LONG) &&
-               (Z_LVAL_PP(v) > 0) && IS_EX_PX_ARG(k))
-            {
+            /* Detect PX or EX argument and validate timeout */
+            if (type == HASH_KEY_IS_STRING && IS_EX_PX_ARG(k)) {
+                /* Set expire type */
                 exp_type = k;
-                expire = Z_LVAL_PP(v);
-            } else if(Z_TYPE_PP(v) == IS_STRING &&
-                      IS_NX_XX_ARG(Z_STRVAL_PP(v)))
-            {
+
+                /* Try to extract timeout */
+                if (Z_TYPE_PP(v) == IS_LONG) {
+                    expire = Z_LVAL_PP(v);
+                } else if (Z_TYPE_PP(v) == IS_STRING) {
+                    expire = atol(Z_STRVAL_PP(v));
+                }
+
+                /* Expiry can't be set < 1 */
+                if (expire < 1) return FAILURE;
+            } else if (Z_TYPE_PP(v) == IS_STRING && IS_EX_PX_ARG(k)) {
                 set_type = Z_STRVAL_PP(v);
             }
         }
     } else if(z_opts && Z_TYPE_P(z_opts) == IS_LONG) {
+        /* Grab expiry and fail if it's < 1 */
         expire = Z_LVAL_P(z_opts);
+        if (expire < 1) return FAILURE;
     }
 
     /* Now let's construct the command we want */