mapped_file.cc 2.0 KB

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  1. // Copyright 2017 The Chromium Authors. All rights reserved.
  2. // Use of this source code is governed by a BSD-style license that can be
  3. // found in the LICENSE file.
  4. #include "components/zucchini/mapped_file.h"
  5. #include <utility>
  6. #include "base/files/file_util.h"
  7. #include "build/build_config.h"
  8. namespace zucchini {
  9. MappedFileReader::MappedFileReader(base::File file) {
  10. if (!file.IsValid()) {
  11. error_ = "Invalid file.";
  12. return; // |buffer_| will be uninitialized, and therefore invalid.
  13. }
  14. if (!buffer_.Initialize(std::move(file))) {
  15. error_ = "Can't map file to memory.";
  16. }
  17. }
  18. MappedFileWriter::MappedFileWriter(const base::FilePath& file_path,
  19. base::File file,
  20. size_t length)
  21. : file_path_(file_path), delete_behavior_(kManualDeleteOnClose) {
  22. if (!file.IsValid()) {
  23. error_ = "Invalid file.";
  24. return; // |buffer_| will be uninitialized, and therefore invalid.
  25. }
  26. #if BUILDFLAG(IS_WIN)
  27. file_handle_ = file.Duplicate();
  28. // Tell the OS to delete the file when all handles are closed.
  29. if (file_handle_.DeleteOnClose(true)) {
  30. delete_behavior_ = kAutoDeleteOnClose;
  31. } else {
  32. error_ = "Failed to mark file for delete-on-close.";
  33. }
  34. #endif // BUILDFLAG(IS_WIN)
  35. bool is_ok = buffer_.Initialize(std::move(file), {0, length},
  36. base::MemoryMappedFile::READ_WRITE_EXTEND);
  37. if (!is_ok) {
  38. error_ = "Can't map file to memory.";
  39. }
  40. }
  41. MappedFileWriter::~MappedFileWriter() {
  42. if (!HasError() && delete_behavior_ == kManualDeleteOnClose &&
  43. !file_path_.empty() && !base::DeleteFile(file_path_)) {
  44. error_ = "Failed to delete file.";
  45. }
  46. }
  47. bool MappedFileWriter::Keep() {
  48. #if BUILDFLAG(IS_WIN)
  49. if (delete_behavior_ == kAutoDeleteOnClose &&
  50. !file_handle_.DeleteOnClose(false)) {
  51. error_ = "Failed to prevent deletion of file.";
  52. return false;
  53. }
  54. #endif // BUILDFLAG(IS_WIN)
  55. delete_behavior_ = kKeep;
  56. return true;
  57. }
  58. } // namespace zucchini