1 //===----------------------------- Registers.hpp --------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is dual licensed under the MIT and the University of Illinois Open 6 // Source Licenses. See LICENSE.TXT for details. 7 // 8 // 9 // Abstract interface to shared reader/writer log, hiding platform and 10 // configuration differences. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef __RWMUTEX_HPP__ 15 #define __RWMUTEX_HPP__ 16 17 #if defined(_WIN32) 18 #include <windows.h> 19 #elif !defined(_LIBUNWIND_HAS_NO_THREADS) 20 #include <pthread.h> 21 #endif 22 23 namespace libunwind { 24 25 #if defined(_LIBUNWIND_HAS_NO_THREADS) 26 27 class _LIBUNWIND_HIDDEN RWMutex { 28 public: lock_shared()29 bool lock_shared() { return true; } unlock_shared()30 bool unlock_shared() { return true; } lock()31 bool lock() { return true; } unlock()32 bool unlock() { return true; } 33 }; 34 35 #elif defined(_WIN32) 36 37 class _LIBUNWIND_HIDDEN RWMutex { 38 public: 39 bool lock_shared() { 40 AcquireSRWLockShared(&_lock); 41 return true; 42 } 43 bool unlock_shared() { 44 ReleaseSRWLockShared(&_lock); 45 return true; 46 } 47 bool lock() { 48 AcquireSRWLockExclusive(&_lock); 49 return true; 50 } 51 bool unlock() { 52 ReleaseSRWLockExclusive(&_lock); 53 return true; 54 } 55 56 private: 57 SRWLOCK _lock = SRWLOCK_INIT; 58 }; 59 60 #else 61 62 class _LIBUNWIND_HIDDEN RWMutex { 63 public: 64 bool lock_shared() { return pthread_rwlock_rdlock(&_lock) == 0; } 65 bool unlock_shared() { return pthread_rwlock_unlock(&_lock) == 0; } 66 bool lock() { return pthread_rwlock_wrlock(&_lock) == 0; } 67 bool unlock() { return pthread_rwlock_unlock(&_lock) == 0; } 68 69 private: 70 pthread_rwlock_t _lock = PTHREAD_RWLOCK_INITIALIZER; 71 }; 72 73 #endif 74 75 } // namespace libunwind 76 77 #endif // __RWMUTEX_HPP__ 78