diff -r 000000000000 -r 6474c204b198 dom/camera/CameraCommon.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/camera/CameraCommon.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,64 @@
+/* -*- Mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; tab-width: 40 -*- */
+/* vim: set ts=2 et sw=2 tw=40: */
+/* 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 DOM_CAMERA_CAMERACOMMON_H
+#define DOM_CAMERA_CAMERACOMMON_H
+
+#ifndef __func__
+#ifdef __FUNCTION__
+#define __func__ __FUNCTION__
+#else
+#define __func__ __FILE__
+#endif
+#endif
+
+#ifndef NAN
+#define NAN std::numeric_limits<double>::quiet_NaN()
+#endif
+
+#include "prlog.h"
+
+#ifdef PR_LOGGING
+extern PRLogModuleInfo* GetCameraLog();
+#define DOM_CAMERA_LOG( type, ... ) PR_LOG(GetCameraLog(), (PRLogModuleLevel)type, ( __VA_ARGS__ ))
+#else
+#define DOM_CAMERA_LOG( type, ... )
+#endif
+
+#define DOM_CAMERA_LOGA( ... )      DOM_CAMERA_LOG( 0, __VA_ARGS__ )
+
+/**
+ * From the least to the most output.
+ */
+enum {
+  DOM_CAMERA_LOG_NOTHING,
+  DOM_CAMERA_LOG_ERROR,
+  DOM_CAMERA_LOG_WARNING,
+  DOM_CAMERA_LOG_INFO,
+  DOM_CAMERA_LOG_TRACE,
+  DOM_CAMERA_LOG_REFERENCES
+};
+
+/**
+ * DOM_CAMERA_LOGR() can be called before 'gCameraLog' is set, so
+ * we need to handle this one a little differently.
+ */
+#ifdef PR_LOGGING
+#define DOM_CAMERA_LOGR( ... )                                  \
+  do {                                                          \
+    if (GetCameraLog()) {                                       \
+      DOM_CAMERA_LOG( DOM_CAMERA_LOG_REFERENCES, __VA_ARGS__ ); \
+    }                                                           \
+  } while (0)
+#else
+#define DOM_CAMERA_LOGR( ... )
+#endif
+#define DOM_CAMERA_LOGT( ... )      DOM_CAMERA_LOG( DOM_CAMERA_LOG_TRACE, __VA_ARGS__ )
+#define DOM_CAMERA_LOGI( ... )      DOM_CAMERA_LOG( DOM_CAMERA_LOG_INFO, __VA_ARGS__ )
+#define DOM_CAMERA_LOGW( ... )      DOM_CAMERA_LOG( DOM_CAMERA_LOG_WARNING, __VA_ARGS__ )
+#define DOM_CAMERA_LOGE( ... )      DOM_CAMERA_LOG( DOM_CAMERA_LOG_ERROR, __VA_ARGS__ )
+
+#endif // DOM_CAMERA_CAMERACOMMON_H