1 files changed, 339 insertions, 0 deletions
diff --git a/xpcom/base/nsWindowsHelpers.h b/xpcom/base/nsWindowsHelpers.h
new file mode 100644
index 0000000000..7c91275803
--- /dev/null
+++ b/xpcom/base/nsWindowsHelpers.h
@@ -0,0 +1,339 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// NB: This code may be used from non-XPCOM code, in particular, the
+// Windows Default Browser Agent.
+
+#ifndef nsWindowsHelpers_h
+#define nsWindowsHelpers_h
+
+#include <windows.h>
+#include <msi.h>
+#include "nsAutoRef.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/UniquePtr.h"
+
+// ----------------------------------------------------------------------------
+// Critical Section helper class
+// ----------------------------------------------------------------------------
+
+class AutoCriticalSection {
+ public:
+  explicit AutoCriticalSection(LPCRITICAL_SECTION aSection)
+      : mSection(aSection) {
+    ::EnterCriticalSection(mSection);
+  }
+  ~AutoCriticalSection() { ::LeaveCriticalSection(mSection); }
+
+ private:
+  LPCRITICAL_SECTION mSection;
+};
+
+template <>
+class nsAutoRefTraits<HKEY> {
+ public:
+  typedef HKEY RawRef;
+  static HKEY Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      RegCloseKey(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<HDC> {
+ public:
+  typedef HDC RawRef;
+  static HDC Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      ::DeleteDC(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<HFONT> {
+ public:
+  typedef HFONT RawRef;
+  static HFONT Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      ::DeleteObject(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<HBRUSH> {
+ public:
+  typedef HBRUSH RawRef;
+  static HBRUSH Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      ::DeleteObject(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<HRGN> {
+ public:
+  typedef HRGN RawRef;
+  static HRGN Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      ::DeleteObject(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<HBITMAP> {
+ public:
+  typedef HBITMAP RawRef;
+  static HBITMAP Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      ::DeleteObject(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<SC_HANDLE> {
+ public:
+  typedef SC_HANDLE RawRef;
+  static SC_HANDLE Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      CloseServiceHandle(aFD);
+    }
+  }
+};
+
+template <>
+class nsSimpleRef<HANDLE> {
+ protected:
+  typedef HANDLE RawRef;
+
+  nsSimpleRef() : mRawRef(nullptr) {}
+
+  explicit nsSimpleRef(RawRef aRawRef) : mRawRef(aRawRef) {}
+
+  bool HaveResource() const {
+    return mRawRef && mRawRef != INVALID_HANDLE_VALUE;
+  }
+
+ public:
+  RawRef get() const { return mRawRef; }
+
+  static void Release(RawRef aRawRef) {
+    if (aRawRef && aRawRef != INVALID_HANDLE_VALUE) {
+      CloseHandle(aRawRef);
+    }
+  }
+  RawRef mRawRef;
+};
+
+template <>
+class nsAutoRefTraits<HMODULE> {
+ public:
+  typedef HMODULE RawRef;
+  static RawRef Void() { return nullptr; }
+
+  static void Release(RawRef aFD) {
+    if (aFD != Void()) {
+      FreeLibrary(aFD);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<DEVMODEW*> {
+ public:
+  typedef DEVMODEW* RawRef;
+  static RawRef Void() { return nullptr; }
+
+  static void Release(RawRef aDevMode) {
+    if (aDevMode != Void()) {
+      ::HeapFree(::GetProcessHeap(), 0, aDevMode);
+    }
+  }
+};
+
+template <>
+class nsAutoRefTraits<MSIHANDLE> {
+ public:
+  typedef MSIHANDLE RawRef;
+  static RawRef Void() { return 0; }
+
+  static void Release(RawRef aHandle) {
+    if (aHandle != Void()) {
+      ::MsiCloseHandle(aHandle);
+    }
+  }
+};
+
+// HGLOBAL is just a typedef of HANDLE which nsSimpleRef has a specialization
+// of, that means having a nsAutoRefTraits specialization for HGLOBAL is
+// useless. Therefore we create a wrapper class for HGLOBAL to make
+// nsAutoRefTraits and nsAutoRef work as intention.
+class nsHGLOBAL {
+ public:
+  MOZ_IMPLICIT nsHGLOBAL(HGLOBAL hGlobal) : m_hGlobal(hGlobal) {}
+
+  operator HGLOBAL() const { return m_hGlobal; }
+
+ private:
+  HGLOBAL m_hGlobal;
+};
+
+template <>
+class nsAutoRefTraits<nsHGLOBAL> {
+ public:
+  typedef nsHGLOBAL RawRef;
+  static RawRef Void() { return nullptr; }
+
+  static void Release(RawRef hGlobal) { ::GlobalFree(hGlobal); }
+};
+
+// Because Printer's HANDLE uses ClosePrinter and we already have
+// nsAutoRef<HANDLE> which uses CloseHandle so we need to create a wrapper class
+// for HANDLE to have another specialization for nsAutoRefTraits.
+class nsHPRINTER {
+ public:
+  MOZ_IMPLICIT nsHPRINTER(HANDLE hPrinter) : m_hPrinter(hPrinter) {}
+
+  operator HANDLE() const { return m_hPrinter; }
+
+  HANDLE* operator&() { return &m_hPrinter; }
+
+ private:
+  HANDLE m_hPrinter;
+};
+
+// winspool.h header has AddMonitor macro, it conflicts with AddMonitor member
+// function in TaskbarPreview.cpp and TaskbarTabPreview.cpp. Beside, we only
+// need ClosePrinter here for Release function, so having its prototype is
+// enough.
+extern "C" BOOL WINAPI ClosePrinter(HANDLE hPrinter);
+
+template <>
+class nsAutoRefTraits<nsHPRINTER> {
+ public:
+  typedef nsHPRINTER RawRef;
+  static RawRef Void() { return nullptr; }
+
+  static void Release(RawRef hPrinter) { ::ClosePrinter(hPrinter); }
+};
+
+typedef nsAutoRef<HKEY> nsAutoRegKey;
+typedef nsAutoRef<HDC> nsAutoHDC;
+typedef nsAutoRef<HFONT> nsAutoFont;
+typedef nsAutoRef<HBRUSH> nsAutoBrush;
+typedef nsAutoRef<HRGN> nsAutoRegion;
+typedef nsAutoRef<HBITMAP> nsAutoBitmap;
+typedef nsAutoRef<SC_HANDLE> nsAutoServiceHandle;
+typedef nsAutoRef<HANDLE> nsAutoHandle;
+typedef nsAutoRef<HMODULE> nsModuleHandle;
+typedef nsAutoRef<DEVMODEW*> nsAutoDevMode;
+typedef nsAutoRef<nsHGLOBAL> nsAutoGlobalMem;
+typedef nsAutoRef<nsHPRINTER> nsAutoPrinter;
+typedef nsAutoRef<MSIHANDLE> nsAutoMsiHandle;
+
+// Construct a path "<system32>\<aModule>". return false if the output buffer
+// is too small.
+// Note: If the system path cannot be found, or doesn't fit in the output buffer
+// with the module name, we will just ignore the system path and output the
+// module name alone;
+// this may mean using a normal search path wherever the output is used.
+bool inline ConstructSystem32Path(LPCWSTR aModule, WCHAR* aSystemPath,
+                                  UINT aSize) {
+  MOZ_ASSERT(aSystemPath);
+
+  size_t fileLen = wcslen(aModule);
+  if (fileLen >= aSize) {
+    // The module name alone cannot even fit!
+    return false;
+  }
+
+  size_t systemDirLen = GetSystemDirectoryW(aSystemPath, aSize);
+
+  if (systemDirLen) {
+    if (systemDirLen < aSize - fileLen) {
+      // Make the system directory path terminate with a slash.
+      if (aSystemPath[systemDirLen - 1] != L'\\') {
+        if (systemDirLen + 1 < aSize - fileLen) {
+          aSystemPath[systemDirLen] = L'\\';
+          ++systemDirLen;
+          // No need to re-nullptr terminate.
+        } else {
+          // Couldn't fit the system path with added slash.
+          systemDirLen = 0;
+        }
+      }
+    } else {
+      // Couldn't fit the system path.
+      systemDirLen = 0;
+    }
+  }
+
+  MOZ_ASSERT(systemDirLen + fileLen < aSize);
+
+  wcsncpy(aSystemPath + systemDirLen, aModule, fileLen);
+  aSystemPath[systemDirLen + fileLen] = L'\0';
+  return true;
+}
+
+HMODULE inline LoadLibrarySystem32(LPCWSTR aModule) {
+  return LoadLibraryExW(aModule, nullptr, LOAD_LIBRARY_SEARCH_SYSTEM32);
+}
+
+// for UniquePtr
+struct LocalFreeDeleter {
+  void operator()(void* aPtr) { ::LocalFree(aPtr); }
+};
+
+struct VirtualFreeDeleter {
+  void operator()(void* aPtr) { ::VirtualFree(aPtr, 0, MEM_RELEASE); }
+};
+
+// for UniquePtr to store a PSID
+struct FreeSidDeleter {
+  void operator()(void* aPtr) { ::FreeSid(aPtr); }
+};
+// Unfortunately, although SID is a struct, PSID is a void*
+// This typedef will work for storing a PSID in a UniquePtr and should make
+// things a bit more readable.
+typedef mozilla::UniquePtr<void, FreeSidDeleter> UniqueSidPtr;
+
+struct CloseHandleDeleter {
+  typedef HANDLE pointer;
+  void operator()(pointer aHandle) {
+    if (aHandle != INVALID_HANDLE_VALUE) {
+      ::CloseHandle(aHandle);
+    }
+  }
+};
+
+// One caller of this function is early in startup and several others are not,
+// so they have different ways of determining the two parameters. This function
+// exists just so any future code that needs to determine whether the dynamic
+// blocklist is disabled remembers to check whether safe mode is active.
+inline bool IsDynamicBlocklistDisabled(bool isSafeMode,
+                                       bool hasCommandLineDisableArgument) {
+  return isSafeMode || hasCommandLineDisableArgument;
+}
+#endif