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/* 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 <windows.h>
#include "MemoryMappedFile.h"
#include "private/pprio.h"
namespace mozilla {
MemoryMappedFile MemoryMappedFile::OpenRaw(FileHandle aHandle,
size_t aMaxSize) {
if (!FileHandleIsValid(aHandle)) {
return {};
}
// Validate the file size.
LARGE_INTEGER sizeLI;
if (!GetFileSizeEx(aHandle, &sizeLI) || sizeLI.QuadPart < 0 ||
static_cast<uint64_t>(sizeLI.QuadPart) >
static_cast<uint64_t>(aMaxSize)) {
return {};
}
const size_t size = sizeLI.QuadPart;
// Zero-size needs special handling.
if (size == 0) {
return Empty();
}
UniqueFileHandle mapping(
CreateFileMappingA(aHandle, nullptr, PAGE_READONLY, 0, 0, nullptr));
if (!mapping) {
return {};
}
if (void* data = MapViewOfFile(mapping.get(), FILE_MAP_READ, 0, 0, size)) {
return MemoryMappedFile(data, size);
}
return {};
}
MemoryMappedFile MemoryMappedFile::Open(PRFileDesc* aPRFile, size_t aMaxSize) {
if (!aPRFile) {
return {};
}
const HANDLE handle = (HANDLE)PR_FileDesc2NativeHandle(aPRFile);
return OpenRaw(handle, aMaxSize);
}
void MemoryMappedFile::Unmap() {
if (mSize) {
UnmapViewOfFile((void*)mData);
}
mSize = 0;
mData = nullptr;
}
} // namespace mozilla