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 = PTHREAD_RECURSIVE_MUTEX_INITIALIZER;
  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 LockHelper::LockHelper()
  38 {
  39         dyldGlobalLockAcquire();
  40 }
  41
  42 LockHelper::~LockHelper()
  43 {
  44         dyldGlobalLockRelease();
  45 }
  46
  47 void dyldGlobalLockAcquire()
  48 {
  49         pthread_mutex_lock(&sGlobalMutex);
  50         ++_dyld_global_lock_held;
  51 }
  52
  53 void dyldGlobalLockRelease()
  54 {
  55         --_dyld_global_lock_held;
  56         pthread_mutex_unlock(&sGlobalMutex);
  57 }
  58
  59