sandboxed-api/oss-internship-2020/guetzli/guetzli_transaction.cc
Copybara-Service c663427cf9 Merge pull request #49 from bohdanty:master
PiperOrigin-RevId: 332240434
Change-Id: I9e71cf3d3ab50e3a379e3c651b931ca95692666f
2020-09-17 08:36:07 -07:00

124 lines
3.9 KiB
C++

// Copyright 2020 Google LLC
//
// 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.
#include "guetzli_transaction.h" // NOLINT(build/include)
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <iostream>
#include <memory>
namespace guetzli::sandbox {
absl::Status GuetzliTransaction::Main() {
sapi::v::Fd in_fd(open(params_.in_file, O_RDONLY));
if (in_fd.GetValue() < 0) {
return absl::FailedPreconditionError("Error opening input file");
}
SAPI_ASSIGN_OR_RETURN(image_type_, GetImageTypeFromFd(in_fd.GetValue()));
SAPI_RETURN_IF_ERROR(sandbox()->TransferToSandboxee(&in_fd));
if (in_fd.GetRemoteFd() < 0) {
return absl::FailedPreconditionError(
"Error receiving remote FD: remote input fd is set to -1");
}
GuetzliApi api(sandbox());
sapi::v::LenVal output(0);
sapi::v::Struct<ProcessingParams> processing_params;
*processing_params.mutable_data() = {in_fd.GetRemoteFd(), params_.verbose,
params_.quality, params_.memlimit_mb};
auto result =
image_type_ == ImageType::kJpeg
? api.ProcessJpeg(processing_params.PtrBefore(), output.PtrBefore())
: api.ProcessRgb(processing_params.PtrBefore(), output.PtrBefore());
if (!result.value_or(false)) {
return absl::FailedPreconditionError(absl::StrCat(
"Error processing ", (image_type_ == ImageType::kJpeg ? "jpeg" : "rgb"),
" data"));
}
sapi::v::Fd out_fd(open(".", O_TMPFILE | O_RDWR, S_IRUSR | S_IWUSR));
if (out_fd.GetValue() < 0) {
return absl::FailedPreconditionError("Error creating temp output file");
}
SAPI_RETURN_IF_ERROR(sandbox()->TransferToSandboxee(&out_fd));
if (out_fd.GetRemoteFd() < 0) {
return absl::FailedPreconditionError(
"Error receiving remote FD: remote output fd is set to -1");
}
auto write_result = api.WriteDataToFd(out_fd.GetRemoteFd(), output.PtrNone());
if (!write_result.value_or(false)) {
return absl::FailedPreconditionError("Error writing file inside sandbox");
}
SAPI_RETURN_IF_ERROR(LinkOutFile(out_fd.GetValue()));
return absl::OkStatus();
}
absl::Status GuetzliTransaction::LinkOutFile(int out_fd) const {
if (access(params_.out_file, F_OK) != -1) {
if (remove(params_.out_file) < 0) {
return absl::FailedPreconditionError(absl::StrCat(
"Error deleting existing output file: ", params_.out_file));
}
}
std::string path = absl::StrCat("/proc/self/fd/", out_fd);
if (linkat(AT_FDCWD, path.c_str(), AT_FDCWD, params_.out_file,
AT_SYMLINK_FOLLOW) < 0) {
return absl::FailedPreconditionError(
absl::StrCat("Error linking: ", params_.out_file));
}
return absl::OkStatus();
}
sapi::StatusOr<ImageType> GuetzliTransaction::GetImageTypeFromFd(int fd) const {
static const unsigned char kPNGMagicBytes[] = {
0x89, 'P', 'N', 'G', '\r', '\n', 0x1a, '\n',
};
char read_buf[sizeof(kPNGMagicBytes)];
if (read(fd, read_buf, sizeof(kPNGMagicBytes)) != sizeof(kPNGMagicBytes)) {
return absl::FailedPreconditionError(
"Error determining type of the input file");
}
if (lseek(fd, 0, SEEK_SET) != 0) {
return absl::FailedPreconditionError(
"Error returnig cursor to the beginning");
}
return memcmp(read_buf, kPNGMagicBytes, sizeof(kPNGMagicBytes)) == 0
? ImageType::kPng
: ImageType::kJpeg;
}
} // namespace guetzli::sandbox