xpcom/build/PoisonIOInterposer.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_PoisonIOInterposer_h
   8 #define mozilla_PoisonIOInterposer_h
   9
  10 #include "mozilla/Types.h"
  11 #include <stdio.h>
  12
  13 #ifdef _WIN32
  14 typedef void* platform_handle_t;
  15 #else
  16 typedef int platform_handle_t;
  17 #endif
  18
  19 MOZ_BEGIN_EXTERN_C
  20
  21 /** Register file handle to be ignored by poisoning IO interposer. This function
  22  * and the corresponding UnRegister function are necessary for exchange of
  23  * handles between binaries not using the same CRT on Windows (which happens
  24  * when one of them links the static CRT). In such cases, giving file
  25  * descriptors or FILEs
  26  * doesn't work because _get_osfhandle fails with "invalid parameter". */
  27 void MozillaRegisterDebugHandle(platform_handle_t aHandle);
  28
  29 /** Register file descriptor to be ignored by poisoning IO interposer */
  30 void MozillaRegisterDebugFD(int aFd);
  31
  32 /** Register file to be ignored by poisoning IO interposer */
  33 void MozillaRegisterDebugFILE(FILE* aFile);
  34
  35 /** Unregister file handle from being ignored by poisoning IO interposer */
  36 void MozillaUnRegisterDebugHandle(platform_handle_t aHandle);
  37
  38 /** Unregister file descriptor from being ignored by poisoning IO interposer */
  39 void MozillaUnRegisterDebugFD(int aFd);
  40
  41 /** Unregister file from being ignored by poisoning IO interposer */
  42 void MozillaUnRegisterDebugFILE(FILE* aFile);
  43
  44 MOZ_END_EXTERN_C
  45
  46 #if defined(XP_MACOSX) || defined(XP_WIN)
  47
  48 #  ifdef __cplusplus
  49 namespace mozilla {
  50
  51 /**
  52  * Check if a file is registered as a debug file.
  53  */
  54 bool IsDebugFile(platform_handle_t aFileID);
  55
  56 /**
  57  * Initialize IO poisoning, this is only safe to do on the main-thread when no
  58  * other threads are running.
  59  *
  60  * Please, note that this probably has performance implications as all
  61  */
  62 void InitPoisonIOInterposer();
  63
  64 #    ifdef XP_MACOSX
  65 /**
  66  * Check that writes are dirty before reporting I/O (Mac OS X only)
  67  * This is necessary for late-write checks on Mac OS X, but reading the buffer
  68  * from file to see if we're writing dirty bits is expensive, so we don't want
  69  * to do this for everything else that uses
  70  */
  71 void OnlyReportDirtyWrites();
  72 #    endif /* XP_MACOSX */
  73
  74 /**
  75  * Clear IO poisoning, this is only safe to do on the main-thread when no other
  76  * threads are running.
  77  * Never called! See bug 1647107.
  78  */
  79 void ClearPoisonIOInterposer();
  80
  81 }  // namespace mozilla
  82 #  endif /* __cplusplus */
  83
  84 #else /* defined(XP_MACOSX) || defined(XP_WIN) */
  85
  86 #  ifdef __cplusplus
  87 namespace mozilla {
  88 inline bool IsDebugFile(platform_handle_t aFileID) { return true; }
  89 inline void InitPoisonIOInterposer() {}
  90 inline void ClearPoisonIOInterposer() {}
  91 #    ifdef XP_MACOSX
  92 inline void OnlyReportDirtyWrites() {}
  93 #    endif /* XP_MACOSX */
  94 }  // namespace mozilla
  95 #  endif   /* __cplusplus */
  96
  97 #endif /* XP_WIN || XP_MACOSX */
  98
  99 #endif  // mozilla_PoisonIOInterposer_h