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/* -*- 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
#include "AutoMemMap.h"
#include "ScriptPreloader-inl.h"
#include "mozilla/Unused.h"
#include "mozilla/Try.h"
#include "mozilla/ipc/FileDescriptor.h"
#include "nsIFile.h"
#include <private/pprio.h>
namespace mozilla {
namespace loader {
using namespace mozilla::ipc;
AutoMemMap::~AutoMemMap() { reset(); }
FileDescriptor AutoMemMap::cloneFileDescriptor() const {
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, getter_Transfers(fd)));
return initInternal(prot);
}
Result<Ok, nsresult> AutoMemMap::init(const FileDescriptor& file,
PRFileMapProtect prot, size_t maybeSize) {
MOZ_ASSERT(!fd);
if (!file.IsValid()) {
return Err(NS_ERROR_INVALID_ARG);
}
auto handle = file.ClonePlatformHandle();
fd.reset(PR_ImportFile(PROsfd(handle.get())));
if (!fd) {
return Err(NS_ERROR_FAILURE);
}
Unused << handle.release();
return initInternal(prot, maybeSize);
}
Result<Ok, nsresult> AutoMemMap::initInternal(PRFileMapProtect prot,
size_t maybeSize) {
MOZ_ASSERT(!fileMap);
MOZ_ASSERT(!addr);
if (maybeSize > 0) {
// Some OSes' shared memory objects can't be stat()ed, either at
// all (Android) or without loosening the sandbox (Mac) so just
// use the size.
size_ = maybeSize;
} else {
// But if we don't have the size, assume it's a regular file and
// ask for it.
PRFileInfo64 fileInfo;
MOZ_TRY(PR_GetOpenFileInfo64(fd.get(), &fileInfo));
if (fileInfo.size > UINT32_MAX) {
return Err(NS_ERROR_INVALID_ARG);
}
size_ = fileInfo.size;
}
fileMap = PR_CreateFileMap(fd.get(), 0, prot);
if (!fileMap) {
return Err(NS_ERROR_FAILURE);
}
addr = PR_MemMap(fileMap, 0, size_);
if (!addr) {
return Err(NS_ERROR_FAILURE);
}
return Ok();
}
FileDescriptor AutoMemMap::cloneHandle() const { return cloneFileDescriptor(); }
void AutoMemMap::reset() {
if (addr && !persistent_) {
Unused << NS_WARN_IF(PR_MemUnmap(addr, size()) != PR_SUCCESS);
addr = nullptr;
}
if (fileMap) {
Unused << NS_WARN_IF(PR_CloseFileMap(fileMap) != PR_SUCCESS);
fileMap = nullptr;
}
fd = nullptr;
}
} // namespace loader
} // namespace mozilla