The Tor Browser: tools/profiler/AutoObjectMapper.h@6474c204b198 (annotated)

tools/profiler/AutoObjectMapper.h@6474c204b198 (annotated)

tools/profiler/AutoObjectMapper.h

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /* -*- 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/. */
 #ifndef AutoObjectMapper_h
 #define AutoObjectMapper_h
 #include <string>
 #include "mozilla/Attributes.h"
 #include "PlatformMacros.h"
 // A (nearly-) RAII class that maps an object in and then unmaps it on
 // destruction.  This base class version uses the "normal" POSIX
 // functions: open, fstat, close, mmap, munmap.
 class MOZ_STACK_CLASS AutoObjectMapperPOSIX {
 public:
   // The constructor does not attempt to map the file, because that
   // might fail.  Instead, once the object has been constructed,
   // call Map() to attempt the mapping.  There is no corresponding
   // Unmap() since the unmapping is done in the destructor.  Failure
   // messages are sent to |aLog|.
   AutoObjectMapperPOSIX(void(*aLog)(const char*));
   // Unmap the file on destruction of this object.
   ~AutoObjectMapperPOSIX();
   // Map |fileName| into the address space and return the mapping
   // extents.  If the file is zero sized this will fail.  The file is
   // mapped read-only and private.  Returns true iff the mapping
   // succeeded, in which case *start and *length hold its extent.
   // Once a call to Map succeeds, all subsequent calls to it will
   // fail.
   bool Map(/*OUT*/void** start, /*OUT*/size_t* length, std::string fileName);
 protected:
   // If we are currently holding a mapped object, these record the
   // mapped address range.
   void*  mImage;
   size_t mSize;
   // A logging sink, for complaining about mapping failures.
   void (*mLog)(const char*);
 private:
   // Are we currently holding a mapped object?  This is private to
   // the base class.  Derived classes need to have their own way to
   // track whether they are holding a mapped object.
   bool mIsMapped;
   // Disable copying and assignment.
   AutoObjectMapperPOSIX(const AutoObjectMapperPOSIX&);
   AutoObjectMapperPOSIX& operator=(const AutoObjectMapperPOSIX&);
   // Disable heap allocation of this class.
   void* operator new(size_t);
   void* operator new[](size_t);
   void  operator delete(void*);
   void  operator delete[](void*);
 };
 #if defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
 // This is a variant of AutoObjectMapperPOSIX suitable for use in
 // conjunction with faulty.lib on Android.  How it behaves depends on
 // the name of the file to be mapped.  There are three possible cases:
 //
 // (1) /foo/bar/xyzzy/blah.apk!/libwurble.so
 //     We hand it as-is to faulty.lib and let it fish the relevant
 //     bits out of the APK.
 //
 // (2) libmozglue.so
 //     This is part of the Fennec installation, but is not in the
 //     APK.  Instead we have to figure out the installation path
 //     and look for it there.  Because of faulty.lib limitations,
 //     we have to use regular open/mmap instead of faulty.lib.
 //
 // (3) libanythingelse.so
 //     faulty.lib assumes this is a system library, and prepends
 //     "/system/lib/" to the path.  So as in (1), we can give it
 //     as-is to faulty.lib.
 //
 // Hence (1) and (3) require special-casing here.  Case (2) simply
 // hands the problem to the parent class.
 class MOZ_STACK_CLASS AutoObjectMapperFaultyLib : public AutoObjectMapperPOSIX {
 public:
   AutoObjectMapperFaultyLib(void(*aLog)(const char*));
   ~AutoObjectMapperFaultyLib();
   bool Map(/*OUT*/void** start, /*OUT*/size_t* length, std::string fileName);
 private:
   // faulty.lib requires us to maintain an abstract handle that can be
   // used later to unmap the area.  If this is non-NULL, it is assumed
   // that unmapping is to be done by faulty.lib.  Otherwise it goes
   // via the normal mechanism.
   void* mHdl;
   // Disable copying and assignment.
   AutoObjectMapperFaultyLib(const AutoObjectMapperFaultyLib&);
   AutoObjectMapperFaultyLib& operator=(const AutoObjectMapperFaultyLib&);
   // Disable heap allocation of this class.
   void* operator new(size_t);
   void* operator new[](size_t);
   void  operator delete(void*);
   void  operator delete[](void*);
 };
 #endif // defined(SPS_OS_android) && !defined(MOZ_WIDGET_GONK)
 #endif // AutoObjectMapper_h

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tools/profiler/AutoObjectMapper.h@6474c204b198 (annotated)

tools/profiler/AutoObjectMapper.h