crashpad/util/posix/close_stdio.cc
Mark Mentovai 25c3afaac5 Add CloseStdinAndStdout().
There will be no reason to leave the handler process connected to its
invoker’s stdin or stdout.

On the other hand, I’m currently leaving it connected to the original
and stderr, as these may be useful for diagnostics.

R=rsesek@chromium.org

Review URL: https://codereview.chromium.org/818573002
2014-12-19 14:20:20 -05:00

53 lines
1.6 KiB
C++

// Copyright 2014 The Crashpad Authors. All rights reserved.
//
// 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 "util/posix/close_stdio.h"
#include <fcntl.h>
#include <paths.h>
#include <unistd.h>
#include "base/basictypes.h"
#include "base/files/scoped_file.h"
#include "base/logging.h"
#include "base/posix/eintr_wrapper.h"
namespace crashpad {
namespace {
void CloseStdioStream(int desired_fd, int oflag) {
base::ScopedFD fd(HANDLE_EINTR(open(_PATH_DEVNULL, oflag)));
if (fd == desired_fd) {
// Weird, but play along.
ignore_result(fd.release());
} else {
PCHECK(fd.get() >= 0) << "open";
PCHECK(HANDLE_EINTR(dup2(fd.get(), desired_fd)) != -1) << "dup2";
fd.reset();
}
}
} // namespace
void CloseStdinAndStdout() {
// Open /dev/null for stdin and stdout separately, so that it can be opened
// with the correct mode each time. This ensures that attempts to write to
// stdin or read from stdout fail with EBADF.
CloseStdioStream(STDIN_FILENO, O_RDONLY);
CloseStdioStream(STDOUT_FILENO, O_WRONLY);
}
} // namespace crashpad