+typedef void (*php_http_client_debug_callback_t)(void *arg, struct php_http_client *client, php_http_client_enqueue_t *e, unsigned type, const char *data, size_t size);
+
+#define PHP_HTTP_CLIENT_DEBUG_INFO 0x00
+#define PHP_HTTP_CLIENT_DEBUG_IN 0x01
+#define PHP_HTTP_CLIENT_DEBUG_OUT 0x02
+#define PHP_HTTP_CLIENT_DEBUG_HEADER 0x10
+#define PHP_HTTP_CLIENT_DEBUG_BODY 0x20
+#define PHP_HTTP_CLIENT_DEBUG_SSL 0x40