Add callbacks validate_sid() & update_timestamp() to session handler

Newer session handler API(PS_MOD_UPDATE_TIMESTAMP) supports 2 more callbacks:

* validate_sid() is used by session.use_strict_mode, which provides better security.
* update_timestamp() is used by session.lazy_write, which can improve performance in some situations.

redis_session.c

@@ -61,9 +61,16 @@
 /* Check if a response is the Redis +OK status response */
 #define IS_REDIS_OK(r, len) (r != NULL && len == 3 && !memcmp(r, "+OK", 3))
 
+#if (PHP_MAJOR_VERSION < 7)
 ps_module ps_mod_redis = {
     PS_MOD_SID(redis)
 };
+#else
+ps_module ps_mod_redis = {
+    PS_MOD_UPDATE_TIMESTAMP(redis)
+};
+#endif
+
 ps_module ps_mod_redis_cluster = {
     PS_MOD(rediscluster)
 };
@@ -636,6 +643,105 @@ PS_CREATE_SID_FUNC(redis)
 }
 /* }}} */
 
+#if (PHP_MAJOR_VERSION >= 7)
+/* {{{ PS_VALIDATE_SID_FUNC
+ */
+PS_VALIDATE_SID_FUNC(redis)
+{
+    char *cmd, *response;
+    int cmd_len, response_len;
+#if (PHP_MAJOR_VERSION < 7)
+    const char *skey = key;
+    size_t skeylen = strlen(key);
+#else
+    const char *skey = ZSTR_VAL(key);
+    size_t skeylen = ZSTR_LEN(key);
+#endif
+
+    if (!skeylen) return FAILURE;
+
+    redis_pool *pool = PS_GET_MOD_DATA();
+    redis_pool_member *rpm = redis_pool_get_sock(pool, skey TSRMLS_CC);
+    RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;
+    if (!redis_sock) {
+        return FAILURE;
+    }
+
+    /* send EXISTS command */
+    zend_string *session = redis_session_key(rpm, skey, skeylen);
+    cmd_len = REDIS_SPPRINTF(&cmd, "EXISTS", "S", session);
+    zend_string_release(session);
+    if (redis_sock_write(redis_sock, cmd, cmd_len TSRMLS_CC) < 0) {
+        efree(cmd);
+        return FAILURE;
+    }
+    efree(cmd);
+
+    /* read response */
+    if ((response = redis_sock_read(redis_sock, &response_len TSRMLS_CC)) == NULL) {
+        return FAILURE;
+    }
+
+    if (response_len == 2 && response[0] == ':' && response[1] == '1') {
+        efree(response);
+        return SUCCESS;
+    } else {
+        efree(response);
+        return FAILURE;
+    }
+}
+/* }}} */
+
+/* {{{ PS_UPDATE_TIMESTAMP_FUNC
+ */
+PS_UPDATE_TIMESTAMP_FUNC(redis)
+{
+    char *cmd, *response;
+    int cmd_len, response_len;
+#if (PHP_MAJOR_VERSION < 7)
+    const char *skey = key, *sval = val;
+    size_t skeylen = strlen(key), svallen = vallen;
+#else
+    const char *skey = ZSTR_VAL(key), *sval = ZSTR_VAL(val);
+    size_t skeylen = ZSTR_LEN(key), svallen = ZSTR_LEN(val);
+#endif
+
+    if (!skeylen) return FAILURE;
+
+    redis_pool *pool = PS_GET_MOD_DATA();
+    redis_pool_member *rpm = redis_pool_get_sock(pool, skey TSRMLS_CC);
+    RedisSock *redis_sock = rpm ? rpm->redis_sock : NULL;
+    if (!redis_sock) {
+        return FAILURE;
+    }
+
+    /* send EXPIRE command */
+    zend_string *session = redis_session_key(rpm, skey, skeylen);
+    cmd_len = REDIS_SPPRINTF(&cmd, "EXPIRE", "Sd", session, INI_INT("session.gc_maxlifetime"));
+    zend_string_release(session);
+
+    if (!write_allowed(redis_sock, &pool->lock_status TSRMLS_CC) || redis_sock_write(redis_sock, cmd, cmd_len TSRMLS_CC) < 0) {
+        efree(cmd);
+        return FAILURE;
+    }
+    efree(cmd);
+
+    /* read response */
+    if ((response = redis_sock_read(redis_sock, &response_len TSRMLS_CC)) == NULL) {
+        return FAILURE;
+    }
+
+    if (response_len == 2 && response[0] == ':' && response[1] == '1') {
+        efree(response);
+        return SUCCESS;
+    } else {
+        efree(response);
+        return FAILURE;
+    }
+}
+/* }}} */
+#endif
+
 /* {{{ PS_READ_FUNC
  */
 PS_READ_FUNC(redis)

redis_session.h

@@ -11,6 +11,11 @@ PS_DESTROY_FUNC(redis);
 PS_GC_FUNC(redis);
 PS_CREATE_SID_FUNC(redis);
 
+#if (PHP_MAJOR_VERSION >= 7)
+PS_VALIDATE_SID_FUNC(redis);
+PS_UPDATE_TIMESTAMP_FUNC(redis);
+#endif
+
 PS_OPEN_FUNC(rediscluster);
 PS_CLOSE_FUNC(rediscluster);
 PS_READ_FUNC(rediscluster);