diff -r 000000000000 -r 6474c204b198 xpcom/build/PoisonIOInterposer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/xpcom/build/PoisonIOInterposer.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,81 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* vim:set ts=4 sw=4 sts=4 ci et: */
+/* 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_PoisonIOInterposer_h
+#define mozilla_PoisonIOInterposer_h
+
+#include "mozilla/Types.h"
+#include <stdio.h>
+
+MOZ_BEGIN_EXTERN_C
+
+/** Register file descriptor to be ignored by poisoning IO interposer */
+void MozillaRegisterDebugFD(int fd);
+
+/** Register file to be ignored by poisoning IO interposer */
+void MozillaRegisterDebugFILE(FILE *f);
+
+/** Unregister file descriptor from being ignored by poisoning IO interposer */
+void MozillaUnRegisterDebugFD(int fd);
+
+/** Unregister file from being ignored by poisoning IO interposer */
+void MozillaUnRegisterDebugFILE(FILE *f);
+
+MOZ_END_EXTERN_C
+
+#if defined(XP_WIN) || defined(XP_MACOSX)
+
+#ifdef __cplusplus
+namespace mozilla {
+
+/**
+ * Check if a file is registered as a debug file.
+ */
+bool IsDebugFile(intptr_t aFileID);
+
+/**
+ * Initialize IO poisoning, this is only safe to do on the main-thread when no
+ * other threads are running.
+ *
+ * Please, note that this probably has performance implications as all
+ */
+void InitPoisonIOInterposer();
+
+#ifdef XP_MACOSX
+/**
+ * Check that writes are dirty before reporting I/O (Mac OS X only)
+ * This is necessary for late-write checks on Mac OS X, but reading the buffer
+ * from file to see if we're writing dirty bits is expensive, so we don't want
+ * to do this for everything else that uses
+ */
+void OnlyReportDirtyWrites();
+#endif /* XP_MACOSX */
+
+/**
+ * Clear IO poisoning, this is only safe to do on the main-thread when no other
+ * threads are running.
+ */
+void ClearPoisonIOInterposer();
+
+} // namespace mozilla
+#endif /* __cplusplus */
+
+#else /* XP_WIN || XP_MACOSX */
+
+#ifdef __cplusplus
+namespace mozilla {
+inline bool IsDebugFile(intptr_t aFileID){ return true; }
+inline void InitPoisonIOInterposer(){}
+inline void ClearPoisonIOInterposer(){}
+#ifdef XP_MACOSX
+inline void OnlyReportDirtyWrites(){}
+#endif /* XP_MACOSX */
+} // namespace mozilla
+#endif /* __cplusplus */
+
+#endif /* XP_WIN || XP_MACOSX */
+
+#endif // mozilla_PoisonIOInterposer_h