Support/Windows: Add support modifying memory permissions on Windows. Patch by Aaron Ballman!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@141910 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/Windows/Memory.inc b/lib/Support/Windows/Memory.inc
index 9f69e73..8609d39 100644
--- a/lib/Support/Windows/Memory.inc
+++ b/lib/Support/Windows/Memory.inc
@@ -54,20 +54,62 @@
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) {
- return false;
-}
-
-bool Memory::setRangeWritable(const void *Addr, size_t Size) {
+ 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) {
- return false;
+ 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;
}
}
