1 // Copyright 2023 The Chromium Authors 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include <stdlib.h> 6 #include <string> 7 8 #include "base/containers/span.h" 9 #include "base/files/file_path.h" 10 #include "base/files/file_util.h" 11 #include "base/files/scoped_temp_dir.h" 12 #include "base/logging.h" 13 #include "base/nix/mime_util_xdg.h" 14 15 // Entry point for LibFuzzer. LLVMFuzzerTestOneInput(const uint8_t * data,size_t size)16extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) { 17 base::ScopedTempDir temp_dir; 18 if (!temp_dir.CreateUniqueTempDir()) { 19 // Not a fuzzer error, so we return 0. 20 LOG(ERROR) << "Failed to create temp dir"; 21 return 0; 22 } 23 24 // The parser reads file $XDG_DATA_DIRS/mime/mime.cache. 25 setenv("XDG_DATA_DIRS", temp_dir.GetPath().value().c_str(), 1); 26 base::FilePath mime_dir = temp_dir.GetPath().Append("mime"); 27 base::FilePath mime_cache = mime_dir.Append("mime.cache"); 28 if (!base::CreateDirectory(mime_dir) || 29 !base::WriteFile(mime_cache, base::make_span(data, size))) { 30 LOG(ERROR) << "Failed to create " << mime_cache; 31 // Not a fuzzer error, so we return 0. 32 return 0; 33 } 34 35 base::FilePath dummy_path("foo.txt"); 36 std::string type = base::nix::GetFileMimeType(dummy_path); 37 return 0; 38 } 39