VirtualProtect platform abstraction.

src/xenia/base/memory_win.cc

@@ -0,0 +1,73 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2015 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#include "xenia/base/memory.h"
+
+#include "xenia/base/platform_win.h"
+
+namespace xe {
+namespace memory {
+
+size_t page_size() {
+  static size_t value = 0;
+  if (!value) {
+    SYSTEM_INFO si;
+    GetSystemInfo(&si);
+    value = si.dwAllocationGranularity;
+  }
+  return value;
+}
+
+bool Protect(void* base_address, size_t length, PageAccess access,
+             PageAccess* out_old_access) {
+  if (out_old_access) {
+    *out_old_access = PageAccess::kNoAccess;
+  }
+  DWORD new_protect;
+  switch (access) {
+    case PageAccess::kNoAccess:
+      new_protect = PAGE_NOACCESS;
+      break;
+    case PageAccess::kReadOnly:
+      new_protect = PAGE_READONLY;
+      break;
+    case PageAccess::kReadWrite:
+      new_protect = PAGE_READWRITE;
+      break;
+    default:
+      assert_unhandled_case(access);
+      break;
+  }
+  DWORD old_protect = 0;
+  BOOL result = VirtualProtect(base_address, length, new_protect, &old_protect);
+  if (result) {
+    if (out_old_access) {
+      switch (old_protect) {
+        case PAGE_NOACCESS:
+          *out_old_access = PageAccess::kNoAccess;
+          break;
+        case PAGE_READONLY:
+          *out_old_access = PageAccess::kReadOnly;
+          break;
+        case PAGE_READWRITE:
+          *out_old_access = PageAccess::kReadWrite;
+          break;
+        default:
+          assert_unhandled_case(access);
+          break;
+      }
+    }
+    return true;
+  } else {
+    return false;
+  }
+}
+
+}  // namespace memory
+}  // namespace xe