ladybird/Userland/Utilities/unzip.cpp
Rummskartoffel 4aaab80649 unzip: Don't fail from mmap when trying to decompress empty files
Given an empty file, unzip would try to create a zero-size memory
mapping of that file, which would fail with EINVAL. With this commit,
attempting to unzip an empty file of course still fails, since that's
not a valid PKZIP file, but it now fails for the correct reason and with
the correct error message.
2022-01-15 22:24:19 +02:00

132 lines
4.6 KiB
C++

/*
* Copyright (c) 2020, Andrés Vieira <anvieiravazquez@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Assertions.h>
#include <AK/NumberFormat.h>
#include <LibArchive/Zip.h>
#include <LibCompress/Deflate.h>
#include <LibCore/ArgsParser.h>
#include <LibCore/File.h>
#include <LibCore/MappedFile.h>
#include <LibCore/System.h>
#include <sys/stat.h>
#include <unistd.h>
static bool unpack_zip_member(Archive::ZipMember zip_member, bool quiet)
{
if (zip_member.is_directory) {
if (mkdir(zip_member.name.characters(), 0755) < 0) {
perror("mkdir");
return false;
}
if (!quiet)
outln(" extracting: {}", zip_member.name);
return true;
}
auto new_file = Core::File::construct(zip_member.name);
if (!new_file->open(Core::OpenMode::WriteOnly)) {
warnln("Can't write file {}: {}", zip_member.name, new_file->error_string());
return false;
}
if (!quiet)
outln(" extracting: {}", zip_member.name);
// TODO: verify CRC32s match!
switch (zip_member.compression_method) {
case Archive::ZipCompressionMethod::Store: {
if (!new_file->write(zip_member.compressed_data.data(), zip_member.compressed_data.size())) {
warnln("Can't write file contents in {}: {}", zip_member.name, new_file->error_string());
return false;
}
break;
}
case Archive::ZipCompressionMethod::Deflate: {
auto decompressed_data = Compress::DeflateDecompressor::decompress_all(zip_member.compressed_data);
if (!decompressed_data.has_value()) {
warnln("Failed decompressing file {}", zip_member.name);
return false;
}
if (decompressed_data.value().size() != zip_member.uncompressed_size) {
warnln("Failed decompressing file {}", zip_member.name);
return false;
}
if (!new_file->write(decompressed_data.value().data(), decompressed_data.value().size())) {
warnln("Can't write file contents in {}: {}", zip_member.name, new_file->error_string());
return false;
}
break;
}
default:
VERIFY_NOT_REACHED();
}
if (!new_file->close()) {
warnln("Can't close file {}: {}", zip_member.name, new_file->error_string());
return false;
}
return true;
}
ErrorOr<int> serenity_main(Main::Arguments arguments)
{
const char* path;
int map_size_limit = 32 * MiB;
bool quiet { false };
String output_directory_path;
Core::ArgsParser args_parser;
args_parser.add_option(map_size_limit, "Maximum chunk size to map", "map-size-limit", 0, "size");
args_parser.add_option(output_directory_path, "Directory to receive the archive content", "output-directory", 'd', "path");
args_parser.add_option(quiet, "Be less verbose", "quiet", 'q');
args_parser.add_positional_argument(path, "File to unzip", "path", Core::ArgsParser::Required::Yes);
args_parser.parse(arguments);
String zip_file_path { path };
struct stat st = TRY(Core::System::stat(zip_file_path));
// FIXME: Map file chunk-by-chunk once we have mmap() with offset.
// This will require mapping some parts then unmapping them repeatedly,
// but it would be significantly faster and less syscall heavy than seek()/read() at every read.
if (st.st_size >= map_size_limit) {
warnln("unzip warning: Refusing to map file since it is larger than {}, pass '--map-size-limit {}' to get around this",
human_readable_size(map_size_limit),
round_up_to_power_of_two(st.st_size, 16));
return 1;
}
RefPtr<Core::MappedFile> mapped_file;
ReadonlyBytes input_bytes;
if (st.st_size > 0) {
mapped_file = TRY(Core::MappedFile::map(zip_file_path));
input_bytes = mapped_file->bytes();
}
if (!quiet)
warnln("Archive: {}", zip_file_path);
auto zip_file = Archive::Zip::try_create(input_bytes);
if (!zip_file.has_value()) {
warnln("Invalid zip file {}", zip_file_path);
return 1;
}
if (!output_directory_path.is_null()) {
auto mkdir_error = Core::System::mkdir(output_directory_path, 0755);
if (mkdir_error.is_error() && mkdir_error.error().code() != EEXIST)
return mkdir_error.release_error();
TRY(Core::System::chdir(output_directory_path));
}
auto success = zip_file->for_each_member([&](auto zip_member) {
return unpack_zip_member(zip_member, quiet) ? IterationDecision::Continue : IterationDecision::Break;
});
return success ? 0 : 1;
}