--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/gumbo-parser/src/string_piece.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,48 @@
+// Copyright 2010 Google Inc. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+// Author: jdtang@google.com (Jonathan Tang)
+
+#include "string_piece.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <strings.h>
+
+#include "util.h"
+
+struct GumboInternalParser;
+
+const GumboStringPiece kGumboEmptyString = {NULL, 0};
+
+bool gumbo_string_equals(
+    const GumboStringPiece* str1, const GumboStringPiece* str2) {
+  return str1->length == str2->length &&
+         !memcmp(str1->data, str2->data, str1->length);
+}
+
+bool gumbo_string_equals_ignore_case(
+    const GumboStringPiece* str1, const GumboStringPiece* str2) {
+  return str1->length == str2->length &&
+         !strncasecmp(str1->data, str2->data, str1->length);
+}
+
+void gumbo_string_copy(struct GumboInternalParser* parser,
+    GumboStringPiece* dest, const GumboStringPiece* source) {
+  dest->length = source->length;
+  char* buffer = gumbo_parser_allocate(parser, source->length);
+  memcpy(buffer, source->data, source->length);
+  dest->data = buffer;
+}