sandboxed-api/oss-internship-2020/libpng/examples/example2.cc
Christian Blichmann 75bbd0e1c1 Internal change
Only externally visible changes should be a few changed includes as well as
some formatting changes.

PiperOrigin-RevId: 353226662
Change-Id: Iebf5be13774efcbd94c5d5a17b9b27e47275b229
2021-01-22 06:01:34 -08:00

238 lines
8.0 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 <fcntl.h>
#include <unistd.h>
#include "../sandboxed.h" // NOLINT(build/include)
#include "../tests/libpng.h" // NOLINT(build/include)
struct Data {
int width;
int height;
uint8_t color_type;
uint8_t bit_depth;
int number_of_passes;
size_t rowbytes;
std::unique_ptr<sapi::v::Array<uint8_t>> row_pointers;
};
absl::StatusOr<Data> ReadPng(LibPNGApi& api, absl::string_view infile) {
sapi::v::Fd fd(open(infile.data(), O_RDONLY));
if (fd.GetValue() < 0) {
return absl::InternalError("Error opening input file");
}
SAPI_RETURN_IF_ERROR((&api)->sandbox()->TransferToSandboxee(&fd));
if (fd.GetRemoteFd() < 0) {
return absl::InternalError("Error receiving remote FD");
}
absl::StatusOr<void*> status_or_file;
sapi::v::ConstCStr rb_var("rb");
SAPI_ASSIGN_OR_RETURN(status_or_file,
api.png_fdopen(fd.GetRemoteFd(), rb_var.PtrBefore()));
sapi::v::RemotePtr file(status_or_file.value());
if (!file.GetValue()) {
return absl::InternalError(absl::StrCat("Could not open ", infile));
}
sapi::v::Array<char> header(8);
SAPI_RETURN_IF_ERROR(
api.png_fread(header.PtrBoth(), 1, header.GetSize(), &file));
SAPI_ASSIGN_OR_RETURN(int return_value,
api.png_sig_cmp(header.PtrBoth(), 0, header.GetSize()));
if (return_value != 0) {
return absl::InternalError(absl::StrCat(infile, " is not a PNG file"));
}
absl::StatusOr<png_structp> status_or_png_structp;
sapi::v::ConstCStr ver_string_var(PNG_LIBPNG_VER_STRING);
sapi::v::NullPtr null = sapi::v::NullPtr();
SAPI_ASSIGN_OR_RETURN(
status_or_png_structp,
api.png_create_read_struct_wrapper(ver_string_var.PtrBefore(), &null));
sapi::v::RemotePtr struct_ptr(status_or_png_structp.value());
if (!struct_ptr.GetValue()) {
return absl::InternalError("png_create_read_struct_wrapper failed");
}
absl::StatusOr<png_infop> status_or_png_infop;
SAPI_ASSIGN_OR_RETURN(status_or_png_infop,
api.png_create_info_struct(&struct_ptr));
sapi::v::RemotePtr info_ptr(status_or_png_infop.value());
if (!info_ptr.GetValue()) {
return absl::InternalError("png_create_info_struct failed");
}
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_RETURN_IF_ERROR(api.png_init_io_wrapper(&struct_ptr, &file));
SAPI_RETURN_IF_ERROR(api.png_set_sig_bytes(&struct_ptr, header.GetSize()));
SAPI_RETURN_IF_ERROR(api.png_read_info(&struct_ptr, &info_ptr));
Data data;
SAPI_ASSIGN_OR_RETURN(data.width,
api.png_get_image_width(&struct_ptr, &info_ptr));
SAPI_ASSIGN_OR_RETURN(data.height,
api.png_get_image_height(&struct_ptr, &info_ptr));
SAPI_ASSIGN_OR_RETURN(data.color_type,
api.png_get_color_type(&struct_ptr, &info_ptr));
SAPI_ASSIGN_OR_RETURN(data.bit_depth,
api.png_get_bit_depth(&struct_ptr, &info_ptr));
SAPI_ASSIGN_OR_RETURN(data.number_of_passes,
api.png_set_interlace_handling(&struct_ptr));
SAPI_RETURN_IF_ERROR(api.png_read_update_info(&struct_ptr, &info_ptr));
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_ASSIGN_OR_RETURN(data.rowbytes,
api.png_get_rowbytes(&struct_ptr, &info_ptr));
data.row_pointers =
std::make_unique<sapi::v::Array<uint8_t>>(data.height * data.rowbytes);
SAPI_RETURN_IF_ERROR(api.png_read_image_wrapper(
&struct_ptr, data.row_pointers->PtrAfter(), data.height, data.rowbytes));
SAPI_RETURN_IF_ERROR(api.png_fclose(&file));
return data;
}
absl::Status WritePng(LibPNGApi& api, absl::string_view outfile, Data& data) {
sapi::v::Fd fd(open(outfile.data(), O_WRONLY));
if (fd.GetValue() < 0) {
return absl::InternalError("Error opening output file");
}
SAPI_RETURN_IF_ERROR((&api)->sandbox()->TransferToSandboxee(&fd));
if (fd.GetRemoteFd() < 0) {
return absl::InternalError("Error receiving remote FD");
}
absl::StatusOr<void*> status_or_file;
sapi::v::ConstCStr wb_var("wb");
SAPI_ASSIGN_OR_RETURN(status_or_file,
api.png_fdopen(fd.GetRemoteFd(), wb_var.PtrBefore()));
sapi::v::RemotePtr file(status_or_file.value());
if (!file.GetValue()) {
return absl::InternalError(absl::StrCat("Could not open ", outfile));
}
absl::StatusOr<png_structp> status_or_png_structp;
sapi::v::ConstCStr ver_string_var(PNG_LIBPNG_VER_STRING);
sapi::v::NullPtr null = sapi::v::NullPtr();
SAPI_ASSIGN_OR_RETURN(
status_or_png_structp,
api.png_create_write_struct_wrapper(ver_string_var.PtrBefore(), &null));
sapi::v::RemotePtr struct_ptr(status_or_png_structp.value());
if (!struct_ptr.GetValue()) {
return absl::InternalError("png_create_write_struct_wrapper failed");
}
absl::StatusOr<png_infop> status_or_png_infop;
SAPI_ASSIGN_OR_RETURN(status_or_png_infop,
api.png_create_info_struct(&struct_ptr));
sapi::v::RemotePtr info_ptr(status_or_png_infop.value());
if (!info_ptr.GetValue()) {
return absl::InternalError("png_create_info_struct failed");
}
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_RETURN_IF_ERROR(api.png_init_io_wrapper(&struct_ptr, &file));
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_RETURN_IF_ERROR(
api.png_set_IHDR(&struct_ptr, &info_ptr, data.width, data.height,
data.bit_depth, data.color_type, PNG_INTERLACE_NONE,
PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE));
SAPI_RETURN_IF_ERROR(api.png_write_info(&struct_ptr, &info_ptr));
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_RETURN_IF_ERROR(api.png_write_image_wrapper(
&struct_ptr, data.row_pointers->PtrBefore(), data.height, data.rowbytes));
SAPI_RETURN_IF_ERROR(api.png_setjmp(&struct_ptr));
SAPI_RETURN_IF_ERROR(api.png_write_end(&struct_ptr, &null));
SAPI_RETURN_IF_ERROR(api.png_fclose(&file));
return absl::OkStatus();
}
absl::Status LibPNGMain(const std::string& infile, const std::string& outfile) {
LibPNGSapiSandbox sandbox;
sandbox.AddFile(infile);
sandbox.AddFile(outfile);
SAPI_RETURN_IF_ERROR(sandbox.Init());
LibPNGApi api(&sandbox);
SAPI_ASSIGN_OR_RETURN(Data data, ReadPng(api, infile));
if (data.color_type != PNG_COLOR_TYPE_RGBA &&
data.color_type != PNG_COLOR_TYPE_RGB) {
return absl::InternalError(absl::StrCat(
infile, " has unexpected color type. Expected RGB or RGBA"));
}
size_t channel_count = 3;
if (data.color_type == PNG_COLOR_TYPE_RGBA) {
channel_count = 4;
}
// RGB to BGR
for (size_t i = 0; i != data.height; ++i) {
for (size_t j = 0; j != data.width; ++j) {
uint8_t r = (*data.row_pointers)[i * data.rowbytes + j * channel_count];
uint8_t g =
(*data.row_pointers)[i * data.rowbytes + j * channel_count + 1];
uint8_t b =
(*data.row_pointers)[i * data.rowbytes + j * channel_count + 2];
(*data.row_pointers)[i * data.rowbytes + j * channel_count] = b;
(*data.row_pointers)[i * data.rowbytes + j * channel_count + 2] = r;
}
}
SAPI_RETURN_IF_ERROR(WritePng(api, outfile, data));
return absl::OkStatus();
}
int main(int argc, const char** argv) {
if (argc != 3) {
LOG(ERROR) << "Usage: example5 infile outfile";
return EXIT_FAILURE;
}
auto status = LibPNGMain(argv[1], argv[2]);
if (!status.ok()) {
LOG(ERROR) << "LibPNGMain failed with error:\n"
<< status.ToString() << '\n';
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}