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base / files / scoped_file.cc [blame]
// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/files/scoped_file.h"
#include "base/check.h"
#include "build/build_config.h"
#if BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA)
#include <errno.h>
#include <unistd.h>
#include "base/posix/eintr_wrapper.h"
#endif
namespace base::internal {
#if BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA)
// static
void ScopedFDCloseTraits::Free(int fd) {
// It's important to crash here if something goes wrong.
//
// There are security implications to not closing a file descriptor
// properly. As file descriptors are "capabilities", keeping them open
// would make the current process keep access to a resource. Much of
// Chrome relies on being able to "drop" such access.
//
// It's especially problematic on Linux with the setuid sandbox, where
// a single open directory would bypass the entire security model.
int ret = IGNORE_EINTR(close(fd));
#if BUILDFLAG(IS_LINUX) || BUILDFLAG(IS_CHROMEOS) || BUILDFLAG(IS_APPLE) || \
BUILDFLAG(IS_FUCHSIA) || BUILDFLAG(IS_ANDROID)
// NB: Some file descriptors can return errors from close() e.g. network
// filesystems such as NFS and Linux input devices. On Linux, macOS, and
// Fuchsia's POSIX layer, errors from close other than EBADF do not indicate
// failure to actually close the fd.
if (ret != 0 && errno != EBADF) {
ret = 0;
}
#endif
PCHECK(0 == ret);
}
#endif // BUILDFLAG(IS_POSIX) || BUILDFLAG(IS_FUCHSIA)
} // namespace base::internal