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/*
* Copyright (C) 2020 The Android Open Source Project
*
* 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.
*/
#ifndef ANDROID_APEXD_APEXD_ROLLBACK_UTILS_H_
#define ANDROID_APEXD_APEXD_ROLLBACK_UTILS_H_
#include <filesystem>
#include <string>
#include <android-base/logging.h>
#include <android-base/macros.h>
#include <android-base/result.h>
#include <android-base/scopeguard.h>
#include <logwrap/logwrap.h>
namespace android {
namespace apex {
static constexpr const char* kCpPath = "/system/bin/cp";
/**
* Copies everything including directories from the "from" path to the "to"
* path. Note that this will fail if run before APEXes are mounted, due to a
* dependency on runtime.
*/
inline int32_t CopyDirectoryRecursive(const char* from, const char* to) {
const char* const argv[] = {
kCpPath,
"-F", /* delete any existing destination file first
(--remove-destination) */
"-p", /* preserve timestamps, ownership, and permissions */
"-R", /* recurse into subdirectories (DEST must be a directory) */
"-P", /* Do not follow symlinks [default] */
"-d", /* don't dereference symlinks */
from,
to};
LOG(DEBUG) << "Copying " << from << " to " << to;
return logwrap_fork_execvp(arraysize(argv), argv, nullptr, false, LOG_ALOG,
false, nullptr);
}
/**
* Deletes any files at to_path, and then copies all files and directories
* from from_path into to_path. Note that this must be run after APEXes are
* mounted.
*/
inline android::base::Result<void> ReplaceFiles(const std::string& from_path,
const std::string& to_path) {
namespace fs = std::filesystem;
std::error_code error_code;
fs::remove_all(to_path, error_code);
if (error_code) {
return android::base::Error() << "Failed to delete existing files at "
<< to_path << " : " << error_code.message();
}
auto deleter = [&] {
std::error_code error_code;
fs::remove_all(to_path, error_code);
if (error_code) {
LOG(ERROR) << "Failed to clean up files at " << to_path << " : "
<< error_code.message();
}
};
auto scope_guard = android::base::make_scope_guard(deleter);
int rc = CopyDirectoryRecursive(from_path.c_str(), to_path.c_str());
if (rc != 0) {
return android::base::Error() << "Failed to copy from [" << from_path
<< "] to [" << to_path << "]";
}
scope_guard.Disable();
return {};
}
} // namespace apex
} // namespace android
#endif // ANDROID_APEXD_APEXD_ROLLBACK_UTILS_H_