gecko-dev/ipc/glue/FileDescriptorUtils.cpp

141 строка
3.0 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "FileDescriptorUtils.h"
#include "nsIEventTarget.h"
#include "nsCOMPtr.h"
#include "nsDebug.h"
#include "nsNetCID.h"
#include "nsServiceManagerUtils.h"
#include "nsThreadUtils.h"
#include "prio.h"
#include "private/pprio.h"
#include <errno.h>
#ifdef XP_WIN
#include <io.h>
#else
#include <unistd.h>
#endif
using mozilla::ipc::CloseFileRunnable;
#ifdef DEBUG
CloseFileRunnable::CloseFileRunnable(const FileDescriptor& aFileDescriptor)
: mFileDescriptor(aFileDescriptor)
{
MOZ_ASSERT(aFileDescriptor.IsValid());
}
#endif // DEBUG
CloseFileRunnable::~CloseFileRunnable()
{
if (mFileDescriptor.IsValid()) {
// It's probably safer to take the main thread IO hit here rather than leak
// the file descriptor.
CloseFile();
}
}
NS_IMPL_ISUPPORTS(CloseFileRunnable, nsIRunnable)
void
CloseFileRunnable::Dispatch()
{
nsCOMPtr<nsIEventTarget> eventTarget =
do_GetService(NS_STREAMTRANSPORTSERVICE_CONTRACTID);
NS_ENSURE_TRUE_VOID(eventTarget);
nsresult rv = eventTarget->Dispatch(this, NS_DISPATCH_NORMAL);
NS_ENSURE_SUCCESS_VOID(rv);
}
void
CloseFileRunnable::CloseFile()
{
// It's possible for this to happen on the main thread if the dispatch to the
// stream service fails so we can't assert the thread on which we're running.
MOZ_ASSERT(mFileDescriptor.IsValid());
PRFileDesc* fd =
PR_ImportFile(PROsfd(mFileDescriptor.PlatformHandle()));
NS_WARN_IF_FALSE(fd, "Failed to import file handle!");
mFileDescriptor = FileDescriptor();
if (fd) {
PR_Close(fd);
fd = nullptr;
}
}
NS_IMETHODIMP
CloseFileRunnable::Run()
{
MOZ_ASSERT(!NS_IsMainThread());
CloseFile();
return NS_OK;
}
namespace mozilla {
namespace ipc {
FILE*
FileDescriptorToFILE(const FileDescriptor& aDesc,
const char* aOpenMode)
{
// Debug builds check whether the handle was "used", even if it's
// invalid, so that needs to happen first.
FileDescriptor::PlatformHandleType handle = aDesc.PlatformHandle();
if (!aDesc.IsValid()) {
errno = EBADF;
return nullptr;
}
#ifdef XP_WIN
int fd = _open_osfhandle(reinterpret_cast<intptr_t>(handle), 0);
if (fd == -1) {
CloseHandle(handle);
return nullptr;
}
#else
int fd = handle;
#endif
FILE* file = fdopen(fd, aOpenMode);
if (!file) {
int saved_errno = errno;
close(fd);
errno = saved_errno;
}
return file;
}
FileDescriptor
FILEToFileDescriptor(FILE* aStream)
{
if (!aStream) {
errno = EBADF;
return FileDescriptor();
}
#ifdef XP_WIN
int fd = _fileno(aStream);
if (fd == -1) {
return FileDescriptor();
}
return FileDescriptor(reinterpret_cast<HANDLE>(_get_osfhandle(fd)));
#else
return FileDescriptor(fileno(aStream));
#endif
}
} // namespace ipc
} // namespace mozilla