gecko-dev/js/xpconnect/loader/AutoMemMap.cpp

98 строки
2.2 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim: set ts=8 sts=4 et sw=4 tw=99: */
/* 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 "AutoMemMap.h"
#include "ScriptPreloader-inl.h"
#include "mozilla/Unused.h"
#include "nsIFile.h"
#include <private/pprio.h>
namespace mozilla {
namespace loader {
using namespace mozilla::ipc;
AutoMemMap::~AutoMemMap()
{
if (fileMap) {
if (addr) {
Unused << NS_WARN_IF(PR_MemUnmap(addr, size()) != PR_SUCCESS);
addr = nullptr;
}
Unused << NS_WARN_IF(PR_CloseFileMap(fileMap) != PR_SUCCESS);
fileMap = nullptr;
}
}
FileDescriptor
AutoMemMap::cloneFileDescriptor()
{
if (fd.get()) {
auto handle = FileDescriptor::PlatformHandleType(PR_FileDesc2NativeHandle(fd.get()));
return FileDescriptor(handle);
}
return FileDescriptor();
}
Result<Ok, nsresult>
AutoMemMap::init(nsIFile* file, int flags, int mode, PRFileMapProtect prot)
{
MOZ_ASSERT(!fd);
MOZ_TRY(file->OpenNSPRFileDesc(flags, mode, &fd.rwget()));
return initInternal(prot);
}
Result<Ok, nsresult>
AutoMemMap::init(const FileDescriptor& file)
{
MOZ_ASSERT(!fd);
if (!file.IsValid()) {
return Err(NS_ERROR_INVALID_ARG);
}
auto handle = file.ClonePlatformHandle();
fd = PR_ImportFile(PROsfd(handle.get()));
if (!fd) {
return Err(NS_ERROR_FAILURE);
}
Unused << handle.release();
return initInternal();
}
Result<Ok, nsresult>
AutoMemMap::initInternal(PRFileMapProtect prot)
{
MOZ_ASSERT(!fileMap);
MOZ_ASSERT(!addr);
PRFileInfo64 fileInfo;
MOZ_TRY(PR_GetOpenFileInfo64(fd.get(), &fileInfo));
if (fileInfo.size > UINT32_MAX)
return Err(NS_ERROR_INVALID_ARG);
fileMap = PR_CreateFileMap(fd, 0, prot);
if (!fileMap)
return Err(NS_ERROR_FAILURE);
size_ = fileInfo.size;
addr = PR_MemMap(fileMap, 0, size_);
if (!addr)
return Err(NS_ERROR_FAILURE);
return Ok();
}
} // namespace loader
} // namespace mozilla