gecko-dev/ipc/glue/FileDescriptor.cpp

122 lines
2.9 KiB
C++

/* 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 "FileDescriptor.h"
#include "mozilla/Assertions.h"
#include "nsDebug.h"
#ifdef XP_WIN
#include <windows.h>
#define INVALID_HANDLE INVALID_HANDLE_VALUE
#else // XP_WIN
#include <unistd.h>
#ifndef OS_POSIX
#define OS_POSIX
#endif
#include "base/eintr_wrapper.h"
#define INVALID_HANDLE -1
#endif // XP_WIN
using mozilla::ipc::FileDescriptor;
FileDescriptor::FileDescriptor()
: mHandle(INVALID_HANDLE), mHandleCreatedByOtherProcess(false),
mHandleCreatedByOtherProcessWasUsed(false)
{ }
FileDescriptor::FileDescriptor(PlatformHandleType aHandle)
: mHandle(INVALID_HANDLE), mHandleCreatedByOtherProcess(false),
mHandleCreatedByOtherProcessWasUsed(false)
{
DuplicateInCurrentProcess(aHandle);
}
void
FileDescriptor::DuplicateInCurrentProcess(PlatformHandleType aHandle)
{
MOZ_ASSERT_IF(mHandleCreatedByOtherProcess && IsValid(),
mHandleCreatedByOtherProcessWasUsed);
if (IsValid(aHandle)) {
PlatformHandleType newHandle;
#ifdef XP_WIN
if (DuplicateHandle(GetCurrentProcess(), aHandle, GetCurrentProcess(),
&newHandle, 0, FALSE, DUPLICATE_SAME_ACCESS)) {
#else // XP_WIN
if ((newHandle = dup(aHandle)) != INVALID_HANDLE) {
#endif
mHandle = newHandle;
return;
}
NS_WARNING("Failed to duplicate file handle for current process!");
}
mHandle = INVALID_HANDLE;
}
void
FileDescriptor::CloseCurrentProcessHandle()
{
MOZ_ASSERT_IF(mHandleCreatedByOtherProcess && IsValid(),
mHandleCreatedByOtherProcessWasUsed);
// Don't actually close handles created by another process.
if (mHandleCreatedByOtherProcess) {
return;
}
if (IsValid()) {
#ifdef XP_WIN
if (!CloseHandle(mHandle)) {
NS_WARNING("Failed to close file handle for current process!");
}
#else // XP_WIN
HANDLE_EINTR(close(mHandle));
#endif
mHandle = INVALID_HANDLE;
}
}
FileDescriptor::PickleType
FileDescriptor::ShareTo(const FileDescriptor::IPDLPrivate&,
FileDescriptor::ProcessHandle aOtherProcess) const
{
PlatformHandleType newHandle;
#ifdef XP_WIN
if (IsValid()) {
if (DuplicateHandle(GetCurrentProcess(), mHandle, aOtherProcess,
&newHandle, 0, FALSE, DUPLICATE_SAME_ACCESS)) {
return newHandle;
}
NS_WARNING("Failed to duplicate file handle for other process!");
}
return INVALID_HANDLE;
#else // XP_WIN
if (IsValid()) {
newHandle = dup(mHandle);
if (IsValid(newHandle)) {
return base::FileDescriptor(newHandle, /* auto_close */ true);
}
NS_WARNING("Failed to duplicate file handle for other process!");
}
return base::FileDescriptor();
#endif
MOZ_CRASH("Must not get here!");
}
// static
bool
FileDescriptor::IsValid(PlatformHandleType aHandle)
{
return aHandle != INVALID_HANDLE;
}