+PHP_HTTP_API zend_bool _http_encoding_response_start(size_t content_length TSRMLS_DC)
+{
+ if ( php_ob_handler_used("ob_gzhandler" TSRMLS_CC) ||
+ php_ob_handler_used("zlib output compression" TSRMLS_CC)) {
+ HTTP_G(send).gzip_encoding = 0;
+ } else {
+ if (!HTTP_G(send).gzip_encoding) {
+ /* emit a content-length header */
+ if (content_length) {
+ char cl_header_str[128];
+ size_t cl_header_len;
+ cl_header_len = snprintf(cl_header_str, lenof(cl_header_str), "Content-Length: %zu", content_length);
+ http_send_header_string_ex(cl_header_str, cl_header_len, 1);
+ }
+ } else {
+#ifndef HTTP_HAVE_ZLIB
+ HTTP_G(send).gzip_encoding = 0;
+ php_start_ob_buffer_named("ob_gzhandler", 0, 0 TSRMLS_CC);
+#else
+ HashTable *selected;
+ zval zsupported;
+
+ INIT_PZVAL(&zsupported);
+ array_init(&zsupported);
+ add_next_index_stringl(&zsupported, "gzip", lenof("gzip"), 1);
+ add_next_index_stringl(&zsupported, "x-gzip", lenof("x-gzip"), 1);
+ add_next_index_stringl(&zsupported, "deflate", lenof("deflate"), 1);
+
+ HTTP_G(send).gzip_encoding = 0;
+
+ if ((selected = http_negotiate_encoding(&zsupported))) {
+ STATUS hs = FAILURE;
+ char *encoding = NULL;
+ ulong idx;
+
+ if (HASH_KEY_IS_STRING == zend_hash_get_current_key(selected, &encoding, &idx, 0) && encoding) {
+ if (!strcmp(encoding, "gzip") || !strcmp(encoding, "x-gzip")) {
+ if (SUCCESS == (hs = http_send_header_string("Content-Encoding: gzip"))) {
+ HTTP_G(send).gzip_encoding = HTTP_ENCODING_GZIP;
+ }
+ } else if (!strcmp(encoding, "deflate")) {
+ if (SUCCESS == (hs = http_send_header_string("Content-Encoding: deflate"))) {
+ HTTP_G(send).gzip_encoding = HTTP_ENCODING_DEFLATE;
+ }
+ }
+ if (SUCCESS == hs) {
+ http_send_header_string("Vary: Accept-Encoding");
+ }
+ }
+
+ zend_hash_destroy(selected);
+ FREE_HASHTABLE(selected);
+ }
+
+ zval_dtor(&zsupported);
+ return HTTP_G(send).gzip_encoding;
+#endif
+ }
+ }
+ return 0;
+}
+