121 lines
3.6 KiB
C++
121 lines
3.6 KiB
C++
//===- Win32/Memory.cpp - Win32 Memory Implementation -----------*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file provides the Win32 specific implementation of various Memory
|
|
// management utilities
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "Windows.h"
|
|
#include "llvm/Support/DataTypes.h"
|
|
#include "llvm/Support/Process.h"
|
|
|
|
namespace llvm {
|
|
using namespace sys;
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
//=== WARNING: Implementation here must contain only Win32 specific code
|
|
//=== and must not be UNIX code
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
MemoryBlock Memory::AllocateRWX(size_t NumBytes,
|
|
const MemoryBlock *NearBlock,
|
|
std::string *ErrMsg) {
|
|
if (NumBytes == 0) return MemoryBlock();
|
|
|
|
static const size_t pageSize = Process::GetPageSize();
|
|
size_t NumPages = (NumBytes+pageSize-1)/pageSize;
|
|
|
|
PVOID start = NearBlock ? static_cast<unsigned char *>(NearBlock->base()) +
|
|
NearBlock->size() : NULL;
|
|
|
|
void *pa = VirtualAlloc(start, NumPages*pageSize, MEM_RESERVE | MEM_COMMIT,
|
|
PAGE_EXECUTE_READWRITE);
|
|
if (pa == NULL) {
|
|
if (NearBlock) {
|
|
// Try again without the NearBlock hint
|
|
return AllocateRWX(NumBytes, NULL, ErrMsg);
|
|
}
|
|
MakeErrMsg(ErrMsg, "Can't allocate RWX Memory: ");
|
|
return MemoryBlock();
|
|
}
|
|
|
|
MemoryBlock result;
|
|
result.Address = pa;
|
|
result.Size = NumPages*pageSize;
|
|
return result;
|
|
}
|
|
|
|
bool Memory::ReleaseRWX(MemoryBlock &M, std::string *ErrMsg) {
|
|
if (M.Address == 0 || M.Size == 0) return false;
|
|
if (!VirtualFree(M.Address, 0, MEM_RELEASE))
|
|
return MakeErrMsg(ErrMsg, "Can't release RWX Memory: ");
|
|
return false;
|
|
}
|
|
|
|
static DWORD getProtection(const void *addr) {
|
|
MEMORY_BASIC_INFORMATION info;
|
|
if (sizeof(info) == ::VirtualQuery(addr, &info, sizeof(info))) {
|
|
return info.Protect;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
bool Memory::setWritable(MemoryBlock &M, std::string *ErrMsg) {
|
|
if (!setRangeWritable(M.Address, M.Size)) {
|
|
return MakeErrMsg(ErrMsg, "Cannot set memory to writeable: ");
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool Memory::setExecutable(MemoryBlock &M, std::string *ErrMsg) {
|
|
if (!setRangeExecutable(M.Address, M.Size)) {
|
|
return MakeErrMsg(ErrMsg, "Cannot set memory to executable: ");
|
|
}
|
|
return true;
|
|
}
|
|
|
|
bool Memory::setRangeWritable(const void *Addr, size_t Size) {
|
|
DWORD prot = getProtection(Addr);
|
|
if (!prot)
|
|
return false;
|
|
|
|
if (prot == PAGE_EXECUTE || prot == PAGE_EXECUTE_READ) {
|
|
prot = PAGE_EXECUTE_READWRITE;
|
|
} else if (prot == PAGE_NOACCESS || prot == PAGE_READONLY) {
|
|
prot = PAGE_READWRITE;
|
|
}
|
|
|
|
DWORD oldProt;
|
|
sys::Memory::InvalidateInstructionCache(Addr, Size);
|
|
return ::VirtualProtect(const_cast<LPVOID>(Addr), Size, prot, &oldProt)
|
|
== TRUE;
|
|
}
|
|
|
|
bool Memory::setRangeExecutable(const void *Addr, size_t Size) {
|
|
DWORD prot = getProtection(Addr);
|
|
if (!prot)
|
|
return false;
|
|
|
|
if (prot == PAGE_NOACCESS) {
|
|
prot = PAGE_EXECUTE;
|
|
} else if (prot == PAGE_READONLY) {
|
|
prot = PAGE_EXECUTE_READ;
|
|
} else if (prot == PAGE_READWRITE) {
|
|
prot = PAGE_EXECUTE_READWRITE;
|
|
}
|
|
|
|
DWORD oldProt;
|
|
sys::Memory::InvalidateInstructionCache(Addr, Size);
|
|
return ::VirtualProtect(const_cast<LPVOID>(Addr), Size, prot, &oldProt)
|
|
== TRUE;
|
|
}
|
|
|
|
}
|