#ifndef THR_COND_INCLUDED #define THR_COND_INCLUDED /* Copyright (c) 2014, 2024, Oracle and/or its affiliates. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License, version 2.0, as published by the Free Software Foundation. This program is designed to work with certain software (including but not limited to OpenSSL) that is licensed under separate terms, as designated in a particular file or component or in included license documentation. The authors of MySQL hereby grant you an additional permission to link the program and your derivative works with the separately licensed software that they have either included with the program or referenced in the documentation. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0, for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ /** @file include/thr_cond.h MySQL condition variable implementation. There are three "layers": 1) native_cond_*() Functions that map directly down to OS primitives. Windows - ConditionVariable Other OSes - pthread 2) my_cond_*() Functions that use SAFE_MUTEX (default for debug). Otherwise native_cond_*() is used. 3) mysql_cond*() Functions that include Performance Schema instrumentation. See include/mysql/psi/mysql_thread.h */ #include #include #ifdef _WIN32 #include #include "my_systime.h" #endif #include "my_macros.h" #include "my_thread.h" #include "mysql/components/services/bits/thr_cond_bits.h" #include "thr_mutex.h" #ifdef _WIN32 /** Convert abstime to milliseconds */ static DWORD get_milliseconds(const struct timespec *abstime) { /* Convert timespec to millis and subtract current time. my_getsystime() returns time in 100 ns units. */ const ulonglong future = abstime->tv_sec * 1000 + abstime->tv_nsec / 1000000; const ulonglong now = my_getsystime() / 10000; /* Don't allow the timeout to be negative. */ if (future < now) return 0; return (DWORD)(future - now); } #endif /* _WIN32 */ static inline int native_cond_init(native_cond_t *cond) { #ifdef _WIN32 InitializeConditionVariable(cond); return 0; #else /* pthread_condattr_t is not used in MySQL */ return pthread_cond_init(cond, nullptr); #endif } static inline int native_cond_destroy(native_cond_t *cond [[maybe_unused]]) { #ifdef _WIN32 return 0; /* no destroy function */ #else return pthread_cond_destroy(cond); #endif } static inline int native_cond_timedwait(native_cond_t *cond, native_mutex_t *mutex, const struct timespec *abstime) { #ifdef _WIN32 const DWORD timeout = get_milliseconds(abstime); if (!SleepConditionVariableCS(cond, mutex, timeout)) return ETIMEDOUT; return 0; #else return pthread_cond_timedwait(cond, mutex, abstime); #endif } static inline int native_cond_wait(native_cond_t *cond, native_mutex_t *mutex) { #ifdef _WIN32 if (!SleepConditionVariableCS(cond, mutex, INFINITE)) return ETIMEDOUT; return 0; #else return pthread_cond_wait(cond, mutex); #endif } static inline int native_cond_signal(native_cond_t *cond) { #ifdef _WIN32 WakeConditionVariable(cond); return 0; #else return pthread_cond_signal(cond); #endif } static inline int native_cond_broadcast(native_cond_t *cond) { #ifdef _WIN32 WakeAllConditionVariable(cond); return 0; #else return pthread_cond_broadcast(cond); #endif } #ifdef SAFE_MUTEX int safe_cond_wait(native_cond_t *cond, safe_mutex_t *mp, const char *file, uint line); int safe_cond_timedwait(native_cond_t *cond, safe_mutex_t *mp, const struct timespec *abstime, const char *file, uint line); #endif static inline int my_cond_timedwait(native_cond_t *cond, my_mutex_t *mp, const struct timespec *abstime #ifdef SAFE_MUTEX , const char *file, uint line #endif ) { #ifdef SAFE_MUTEX return safe_cond_timedwait(cond, mp->m_u.m_safe_ptr, abstime, file, line); #else return native_cond_timedwait(cond, &mp->m_u.m_native, abstime); #endif } static inline int my_cond_wait(native_cond_t *cond, my_mutex_t *mp #ifdef SAFE_MUTEX , const char *file, uint line #endif ) { #ifdef SAFE_MUTEX return safe_cond_wait(cond, mp->m_u.m_safe_ptr, file, line); #else return native_cond_wait(cond, &mp->m_u.m_native); #endif } #endif /* THR_COND_INCLUDED */