dyld/src/dyldLock.cpp

   1 /* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
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  24
  25 #include <pthread.h>
  26
  27 #include "dyldLock.h"
  28
  29
  30
  31 static pthread_mutex_t  sGlobalMutex;
  32
  33 // <rdar://problem/6361143> Need a way to determine if a gdb call to dlopen() would block
  34 int     __attribute__((visibility("hidden")))                   _dyld_global_lock_held = 0;
  35
  36
  37 //
  38 // This initializer can go away once the following is available:
  39 //     <rdar://problem/4927311> implement PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
  40 //
  41 void dyldGlobalLockInitialize()
  42 {
  43         pthread_mutexattr_t recursiveMutexAttr;
  44         pthread_mutexattr_init(&recursiveMutexAttr);
  45         pthread_mutexattr_settype(&recursiveMutexAttr, PTHREAD_MUTEX_RECURSIVE);
  46         pthread_mutex_init(&sGlobalMutex, &recursiveMutexAttr);
  47 }
  48
  49
  50 LockHelper::LockHelper()
  51 {
  52         dyldGlobalLockAcquire();
  53 }
  54
  55 LockHelper::~LockHelper()
  56 {
  57         dyldGlobalLockRelease();
  58 }
  59
  60 void dyldGlobalLockAcquire()
  61 {
  62         pthread_mutex_lock(&sGlobalMutex);
  63         _dyld_global_lock_held = 1;
  64 }
  65
  66 void dyldGlobalLockRelease()
  67 {
  68         _dyld_global_lock_held = 0;
  69         pthread_mutex_unlock(&sGlobalMutex);
  70 }
  71
  72