1 //===-- Implementation header for exit_handler ------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLVM_LIBC_SRC_STDLIB_EXIT_HANDLER_H 10 #define LLVM_LIBC_SRC_STDLIB_EXIT_HANDLER_H 11 12 #include "src/__support/CPP/mutex.h" // lock_guard 13 #include "src/__support/blockstore.h" 14 #include "src/__support/common.h" 15 #include "src/__support/fixedvector.h" 16 #include "src/__support/macros/config.h" 17 #include "src/__support/threads/mutex.h" 18 19 namespace LIBC_NAMESPACE_DECL { 20 21 using AtExitCallback = void(void *); 22 using StdCAtExitCallback = void(void); 23 constexpr size_t CALLBACK_LIST_SIZE_FOR_TESTS = 1024; 24 25 struct AtExitUnit { 26 AtExitCallback *callback = nullptr; 27 void *payload = nullptr; 28 LIBC_INLINE constexpr AtExitUnit() = default; AtExitUnitAtExitUnit29 LIBC_INLINE constexpr AtExitUnit(AtExitCallback *c, void *p) 30 : callback(c), payload(p) {} 31 }; 32 33 #if defined(LIBC_TARGET_ARCH_IS_GPU) 34 using ExitCallbackList = FixedVector<AtExitUnit, 64>; 35 #elif defined(LIBC_COPT_PUBLIC_PACKAGING) 36 using ExitCallbackList = ReverseOrderBlockStore<AtExitUnit, 32>; 37 #else 38 using ExitCallbackList = FixedVector<AtExitUnit, CALLBACK_LIST_SIZE_FOR_TESTS>; 39 #endif 40 41 // This is handled by the 'atexit' implementation and shared by 'at_quick_exit'. 42 extern Mutex handler_list_mtx; 43 stdc_at_exit_func(void * payload)44LIBC_INLINE void stdc_at_exit_func(void *payload) { 45 reinterpret_cast<StdCAtExitCallback *>(payload)(); 46 } 47 call_exit_callbacks(ExitCallbackList & callbacks)48LIBC_INLINE void call_exit_callbacks(ExitCallbackList &callbacks) { 49 handler_list_mtx.lock(); 50 while (!callbacks.empty()) { 51 AtExitUnit &unit = callbacks.back(); 52 callbacks.pop_back(); 53 handler_list_mtx.unlock(); 54 unit.callback(unit.payload); 55 handler_list_mtx.lock(); 56 } 57 ExitCallbackList::destroy(&callbacks); 58 } 59 add_atexit_unit(ExitCallbackList & callbacks,const AtExitUnit & unit)60LIBC_INLINE int add_atexit_unit(ExitCallbackList &callbacks, 61 const AtExitUnit &unit) { 62 cpp::lock_guard lock(handler_list_mtx); 63 if (callbacks.push_back(unit)) 64 return 0; 65 return -1; 66 } 67 68 } // namespace LIBC_NAMESPACE_DECL 69 70 #endif // LLVM_LIBC_SRC_STDLIB_EXIT_HANDLER_H 71