/*
* Copyright (C) 2016 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.
*/
#include <errno.h>
#include <fcntl.h>
#include <string.h>
#include <string>
#include <vector>
#include <android-base/file.h>
#include <android-base/properties.h>
#include <android-base/stringprintf.h>
#include <android-base/unique_fd.h>
#include <fs_mgr.h>
#include "bootloader.h"
static struct fstab* read_fstab(std::string* err) {
std::string ro_hardware = android::base::GetProperty("ro.hardware", "");
if (ro_hardware.empty()) {
*err = "failed to get ro.hardware";
return nullptr;
}
// The fstab path is always "/fstab.${ro.hardware}".
std::string fstab_path = "/fstab." + ro_hardware;
struct fstab* fstab = fs_mgr_read_fstab(fstab_path.c_str());
if (fstab == nullptr) {
*err = "failed to read " + fstab_path;
}
return fstab;
}
static std::string get_misc_blk_device(std::string* err) {
struct fstab* fstab = read_fstab(err);
if (fstab == nullptr) {
return "";
}
fstab_rec* record = fs_mgr_get_entry_for_mount_point(fstab, "/misc");
if (record == nullptr) {
*err = "failed to find /misc partition";
return "";
}
return record->blk_device;
}
static bool write_bootloader_message(const bootloader_message& boot, std::string* err) {
std::string misc_blk_device = get_misc_blk_device(err);
if (misc_blk_device.empty()) {
return false;
}
android::base::unique_fd fd(open(misc_blk_device.c_str(), O_WRONLY | O_SYNC));
if (fd.get() == -1) {
*err = android::base::StringPrintf("failed to open %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
if (!android::base::WriteFully(fd.get(), &boot, sizeof(boot))) {
*err = android::base::StringPrintf("failed to write %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
// TODO: O_SYNC and fsync duplicates each other?
if (fsync(fd.get()) == -1) {
*err = android::base::StringPrintf("failed to fsync %s: %s", misc_blk_device.c_str(),
strerror(errno));
return false;
}
return true;
}
bool clear_bootloader_message(std::string* err) {
bootloader_message boot = {};
return write_bootloader_message(boot, err);
}
bool write_bootloader_message(const std::vector<std::string>& options, std::string* err) {
bootloader_message boot = {};
strlcpy(boot.command, "boot-recovery", sizeof(boot.command));
strlcpy(boot.recovery, "recovery\n", sizeof(boot.recovery));
for (const auto& s : options) {
strlcat(boot.recovery, s.c_str(), sizeof(boot.recovery));
if (s.back() != '\n') {
strlcat(boot.recovery, "\n", sizeof(boot.recovery));
}
}
return write_bootloader_message(boot, err);
}
extern "C" bool write_bootloader_message(const char* options) {
std::string err;
return write_bootloader_message({options}, &err);
}
