1 files changed, 99 insertions, 0 deletions
diff --git a/widget/windows/WindowsEventLog.h b/widget/windows/WindowsEventLog.h
new file mode 100644
index 0000000000..e98d5077a0
--- /dev/null
+++ b/widget/windows/WindowsEventLog.h
@@ -0,0 +1,99 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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/. */
+
+#ifndef mozilla_WindowsEventLog_h
+#define mozilla_WindowsEventLog_h
+
+/**
+ * Report messages to the Windows Event Log.
+ */
+
+#include <stdio.h>
+#include <windows.h>
+
+#include "mozilla/Attributes.h"
+#include "mozilla/UniquePtr.h"
+
+/**
+ * This header is intended for self-contained, header-only, utility code for
+ * Win32. It may be used outside of xul.dll, in places such as
+ * default-browser-agent.exe or notificationrouter.dll. If your code creates
+ * dependencies on Mozilla libraries, you should put it elsewhere.
+ */
+
+#define MOZ_WIN_EVENT_LOG_ERROR(source, hr) \
+  mozilla::WriteWindowsEventLogHresult(source, hr, __FUNCTION__, __LINE__)
+#define MOZ_WIN_EVENT_LOG_ERROR_MESSAGE(source, format, ...)              \
+  mozilla::WriteWindowsEventLogErrorMessage(source, format, __FUNCTION__, \
+                                            __LINE__, ##__VA_ARGS__)
+
+namespace mozilla {
+
+static void WriteWindowsEventLogErrorBuffer(const wchar_t* eventSourceName,
+                                            const wchar_t* buffer,
+                                            DWORD eventId) {
+  HANDLE source = RegisterEventSourceW(nullptr, eventSourceName);
+  if (!source) {
+    // Not much we can do about this.
+    return;
+  }
+
+  const wchar_t* stringsArray[] = {buffer};
+  ReportEventW(source, EVENTLOG_ERROR_TYPE, 0, eventId, nullptr, 1, 0,
+               stringsArray, nullptr);
+
+  DeregisterEventSource(source);
+}
+
+inline void WriteWindowsEventLogHresult(const wchar_t* eventSourceName,
+                                        HRESULT hr, const char* sourceFile,
+                                        int sourceLine) {
+  const wchar_t* format = L"0x%X in %S:%d";
+  int bufferSize = _scwprintf(format, hr, sourceFile, sourceLine);
+  ++bufferSize;  // Extra character for terminating null
+  mozilla::UniquePtr<wchar_t[]> errorStr =
+      mozilla::MakeUnique<wchar_t[]>(bufferSize);
+
+  _snwprintf_s(errorStr.get(), bufferSize, _TRUNCATE, format, hr, sourceFile,
+               sourceLine);
+
+  WriteWindowsEventLogErrorBuffer(eventSourceName, errorStr.get(), hr);
+}
+
+MOZ_FORMAT_WPRINTF(1, 4)
+inline void WriteWindowsEventLogErrorMessage(const wchar_t* eventSourceName,
+                                             const wchar_t* messageFormat,
+                                             const char* sourceFile,
+                                             int sourceLine, ...) {
+  // First assemble the passed message
+  va_list ap;
+  va_start(ap, sourceLine);
+  int bufferSize = _vscwprintf(messageFormat, ap);
+  ++bufferSize;  // Extra character for terminating null
+  va_end(ap);
+  mozilla::UniquePtr<wchar_t[]> message =
+      mozilla::MakeUnique<wchar_t[]>(bufferSize);
+
+  va_start(ap, sourceLine);
+  vswprintf(message.get(), bufferSize, messageFormat, ap);
+  va_end(ap);
+
+  // Next, assemble the complete error message to print
+  const wchar_t* errorFormat = L"Error: %s (%S:%d)";
+  bufferSize = _scwprintf(errorFormat, message.get(), sourceFile, sourceLine);
+  ++bufferSize;  // Extra character for terminating null
+  mozilla::UniquePtr<wchar_t[]> errorStr =
+      mozilla::MakeUnique<wchar_t[]>(bufferSize);
+
+  _snwprintf_s(errorStr.get(), bufferSize, _TRUNCATE, errorFormat,
+               message.get(), sourceFile, sourceLine);
+
+  WriteWindowsEventLogErrorBuffer(eventSourceName, errorStr.get(), 0);
+}
+
+}  // namespace mozilla
+
+#endif  // mozilla_WindowsEventLog_h