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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2; -*- */
/* 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
#ifndef loader_AutoMemMap_h
#define loader_AutoMemMap_h
#include "mozilla/FileUtils.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/RangedPtr.h"
#include "mozilla/Result.h"
#include <prio.h>
class nsIFile;
namespace mozilla {
namespace ipc {
class FileDescriptor;
}
namespace loader {
class AutoMemMap {
typedef mozilla::ipc::FileDescriptor FileDescriptor;
public:
AutoMemMap() = default;
~AutoMemMap();
Result<Ok, nsresult> init(nsIFile* file, int flags = PR_RDONLY, int mode = 0,
PRFileMapProtect prot = PR_PROT_READONLY);
Result<Ok, nsresult> init(const FileDescriptor& file,
PRFileMapProtect prot = PR_PROT_READONLY,
size_t maybeSize = 0);
// Initializes the mapped memory with a shared memory handle. On
// Unix-like systems, this is identical to the above init() method. On
// Windows, the FileDescriptor must be a handle for a file mapping,
// rather than a file descriptor.
Result<Ok, nsresult> initWithHandle(const FileDescriptor& file, size_t size,
PRFileMapProtect prot = PR_PROT_READONLY);
void reset();
bool initialized() const { return addr; }
uint32_t size() const { return size_; }
template <typename T = void>
RangedPtr<T> get() {
MOZ_ASSERT(addr);
return {static_cast<T*>(addr), size_};
}
template <typename T = void>
const RangedPtr<T> get() const {
MOZ_ASSERT(addr);
return {static_cast<T*>(addr), size_};
}
size_t nonHeapSizeOfExcludingThis() { return size_; }
FileDescriptor cloneFileDescriptor() const;
FileDescriptor cloneHandle() const;
// Makes this mapping persistent. After calling this, the mapped memory
// will remained mapped, even after this instance is destroyed.
void setPersistent() { persistent_ = true; }
private:
Result<Ok, nsresult> initInternal(PRFileMapProtect prot,
size_t maybeSize = 0);
AutoFDClose fd;
PRFileMap* fileMap = nullptr;
#ifdef XP_WIN
// We can't include windows.h in this header, since it gets included
// by some binding headers (which are explicitly incompatible with
// windows.h). So we can't use the HANDLE type here.
void* handle_ = nullptr;
#endif
uint32_t size_ = 0;
void* addr = nullptr;
bool persistent_ = 0;
AutoMemMap(const AutoMemMap&) = delete;
void operator=(const AutoMemMap&) = delete;
};
} // namespace loader
} // namespace mozilla
#endif // loader_AutoMemMap_h