electron/shell/browser/relauncher_linux.cc

70 строки
2.1 KiB
C++

// Copyright (c) 2016 GitHub, Inc.
// Use of this source code is governed by the MIT license that can be
// found in the LICENSE file.
#include "shell/browser/relauncher.h"
#include <fcntl.h>
#include <signal.h>
#include <sys/prctl.h>
#include <sys/signalfd.h>
#include "base/files/file_util.h"
#include "base/files/scoped_file.h"
#include "base/logging.h"
#include "base/process/launch.h"
#include "base/synchronization/waitable_event.h"
namespace relauncher::internal {
// this is global to be visible to the sa_handler
base::WaitableEvent parentWaiter;
void RelauncherSynchronizeWithParent() {
base::ScopedFD relauncher_sync_fd(kRelauncherSyncFD);
static const auto signum = SIGUSR2;
// send signum to current process when parent process ends.
if (HANDLE_EINTR(prctl(PR_SET_PDEATHSIG, signum)) != 0) {
PLOG(ERROR) << "prctl";
return;
}
// set up a signum handler
struct sigaction action;
memset(&action, 0, sizeof(action));
action.sa_handler = [](int /*signum*/) { parentWaiter.Signal(); };
if (sigaction(signum, &action, nullptr) != 0) {
PLOG(ERROR) << "sigaction";
return;
}
// write a '\0' character to the pipe to the parent process.
// this is how the parent knows that we're ready for it to exit.
if (HANDLE_EINTR(write(relauncher_sync_fd.get(), "", 1)) != 1) {
PLOG(ERROR) << "write";
return;
}
// Wait for the parent to exit
parentWaiter.Wait();
}
int LaunchProgram(const StringVector& relauncher_args,
const StringVector& argv) {
// Redirect the stdout of child process to /dev/null, otherwise after
// relaunch the child process will raise exception when writing to stdout.
base::ScopedFD devnull(HANDLE_EINTR(open("/dev/null", O_WRONLY)));
base::LaunchOptions options;
options.allow_new_privs = true;
options.new_process_group = true; // detach
options.fds_to_remap.emplace_back(devnull.get(), STDERR_FILENO);
options.fds_to_remap.emplace_back(devnull.get(), STDOUT_FILENO);
base::Process process = base::LaunchProcess(argv, options);
return process.IsValid() ? 0 : 1;
}
} // namespace relauncher::internal