[Zucchini] Refactor Zucchini-gen in zucchini_io layer.

This CL moves Zucchini-gen invocation code from zucchini_commands.cc
(in target zucchini) to zucchini_integration.cc (in target zucchini_io)
to clean up layering in Zucchini API, i.e.:
- zucchini_lib: Operates on buffers only.
- zucchini_io: Adds files interface, uses memory-mapped I/O.
- zucchini: Stand-alone executable that parses command-line arguments.

Other changes:
- Rename zucchini_lib functions (zuchcini.h), to dedup names and
  emphasize that these functions operate on buffers:
  - GenerateEnsemble() -> GenerateBuffer(),
  - GenerateEnsembleWithImposedMatches() -> GenerateBufferImposed(),
  - GenerateRaw() -> GenerateBufferRaw(),
  - Apply() -> ApplyBuffer().
  These renames only affect Zucchini and various tests.
- Variable renames and parameter reordering in zucchini_integration.cc.
- Remove '-dd' param in help text of Zucchini-detect (was never ported
  from Trunk, and has been recently deleted there as well).
- Replace all base::File&& with base::File.
- Miscellaneous cleanup for header include.
- Update README.md.

Change-Id: I835b80d4d3d7b291fa822a7a89dab225bf9171e9
Reviewed-on: https://chromium-review.googlesource.com/1105625
Reviewed-by: Samuel Huang <huangs@chromium.org>
Reviewed-by: Greg Thompson <grt@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#569274}
NOKEYCHECK=True
GitOrigin-RevId: 9f0f325d6e2595deb8d50c77e0464946f3bf1ec1

1 files changed, 5 insertions, 61 deletions

diff --git a/zucchini_commands.cc b/zucchini_commands.cc
index 62dd20d..1abe08f 100644
--- a/zucchini_commands.cc
+++ b/zucchini_commands.cc
@@ -38,67 +38,11 @@ constexpr char kSwitchRaw[] = "raw";
 
 zucchini::status::Code MainGen(MainParams params) {
   CHECK_EQ(3U, params.file_paths.size());
-
-  // TODO(huangs): Move implementation to zucchini_integration.cc.
-  using base::File;
-  File old_file(params.file_paths[0], File::FLAG_OPEN | File::FLAG_READ);
-  zucchini::MappedFileReader old_image(std::move(old_file));
-  if (old_image.HasError()) {
-    LOG(ERROR) << "Error with file " << params.file_paths[0].value() << ": "
-               << old_image.error();
-    return zucchini::status::kStatusFileReadError;
-  }
-  File new_file(params.file_paths[1], File::FLAG_OPEN | File::FLAG_READ);
-  zucchini::MappedFileReader new_image(std::move(new_file));
-  if (new_image.HasError()) {
-    LOG(ERROR) << "Error with file " << params.file_paths[1].value() << ": "
-               << new_image.error();
-    return zucchini::status::kStatusFileReadError;
-  }
-  zucchini::EnsemblePatchWriter patch_writer(old_image.region(),
-                                             new_image.region());
-
-  zucchini::status::Code result = zucchini::status::kStatusSuccess;
-  if (params.command_line.HasSwitch(kSwitchRaw)) {
-    result = GenerateRaw(old_image.region(), new_image.region(), &patch_writer);
-  } else {
-    // May be empty.
-    std::string imposed_matches =
-        params.command_line.GetSwitchValueASCII(kSwitchImpose);
-    result = GenerateEnsembleWithImposedMatches(
-        old_image.region(), new_image.region(), std::move(imposed_matches),
-        &patch_writer);
-  }
-
-  if (result != zucchini::status::kStatusSuccess) {
-    params.out << "Fatal error encountered when generating patch." << std::endl;
-    return result;
-  }
-
-  // By default, delete patch on destruction, to avoid having lingering files in
-  // case of a failure. On Windows deletion can be done by the OS.
-  File patch_file(params.file_paths[2], File::FLAG_CREATE_ALWAYS |
-                                            File::FLAG_READ | File::FLAG_WRITE |
-                                            File::FLAG_SHARE_DELETE |
-                                            File::FLAG_CAN_DELETE_ON_CLOSE);
-  zucchini::MappedFileWriter patch(params.file_paths[2], std::move(patch_file),
-                                   patch_writer.SerializedSize());
-  if (patch.HasError()) {
-    LOG(ERROR) << "Error with file " << params.file_paths[2].value() << ": "
-               << patch.error();
-    return zucchini::status::kStatusFileWriteError;
-  }
-
-  if (params.command_line.HasSwitch(kSwitchKeep))
-    patch.Keep();
-
-  if (!patch_writer.SerializeInto(patch.region()))
-    return zucchini::status::kStatusPatchWriteError;
-
-  // Successfully created patch. Explicitly request file to be kept.
-  if (!patch.Keep())
-    return zucchini::status::kStatusFileWriteError;
-  return zucchini::status::kStatusSuccess;
+  return zucchini::Generate(
+      params.file_paths[0], params.file_paths[1], params.file_paths[2],
+      params.command_line.HasSwitch(kSwitchKeep),
+      params.command_line.HasSwitch(kSwitchRaw),
+      params.command_line.GetSwitchValueASCII(kSwitchImpose));
 }
 
 zucchini::status::Code MainApply(MainParams params) {