diff options
Diffstat (limited to '3rdparty/SDL2/src/thread/stdcpp/SDL_syscond.cpp')
-rw-r--r-- | 3rdparty/SDL2/src/thread/stdcpp/SDL_syscond.cpp | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/3rdparty/SDL2/src/thread/stdcpp/SDL_syscond.cpp b/3rdparty/SDL2/src/thread/stdcpp/SDL_syscond.cpp new file mode 100644 index 00000000000..976bff48792 --- /dev/null +++ b/3rdparty/SDL2/src/thread/stdcpp/SDL_syscond.cpp @@ -0,0 +1,164 @@ +/* + Simple DirectMedia Layer + Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org> + + This software is provided 'as-is', without any express or implied + warranty. In no event will the authors be held liable for any damages + arising from the use of this software. + + Permission is granted to anyone to use this software for any purpose, + including commercial applications, and to alter it and redistribute it + freely, subject to the following restrictions: + + 1. The origin of this software must not be misrepresented; you must not + claim that you wrote the original software. If you use this software + in a product, an acknowledgment in the product documentation would be + appreciated but is not required. + 2. Altered source versions must be plainly marked as such, and must not be + misrepresented as being the original software. + 3. This notice may not be removed or altered from any source distribution. +*/ +#include "../../SDL_internal.h" + +extern "C" { +#include "SDL_thread.h" +} + +#include <chrono> +#include <condition_variable> +#include <ratio> +#include <system_error> + +#include "SDL_sysmutex_c.h" + +struct SDL_cond +{ + std::condition_variable_any cpp_cond; +}; + +/* Create a condition variable */ +extern "C" +SDL_cond * +SDL_CreateCond(void) +{ + /* Allocate and initialize the condition variable */ + try { + SDL_cond * cond = new SDL_cond; + return cond; + } catch (std::system_error & ex) { + SDL_SetError("unable to create a C++ condition variable: code=%d; %s", ex.code(), ex.what()); + return NULL; + } catch (std::bad_alloc &) { + SDL_OutOfMemory(); + return NULL; + } +} + +/* Destroy a condition variable */ +extern "C" +void +SDL_DestroyCond(SDL_cond * cond) +{ + if (cond) { + delete cond; + } +} + +/* Restart one of the threads that are waiting on the condition variable */ +extern "C" +int +SDL_CondSignal(SDL_cond * cond) +{ + if (!cond) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + cond->cpp_cond.notify_one(); + return 0; +} + +/* Restart all threads that are waiting on the condition variable */ +extern "C" +int +SDL_CondBroadcast(SDL_cond * cond) +{ + if (!cond) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + cond->cpp_cond.notify_all(); + return 0; +} + +/* Wait on the condition variable for at most 'ms' milliseconds. + The mutex must be locked before entering this function! + The mutex is unlocked during the wait, and locked again after the wait. + +Typical use: + +Thread A: + SDL_LockMutex(lock); + while ( ! condition ) { + SDL_CondWait(cond, lock); + } + SDL_UnlockMutex(lock); + +Thread B: + SDL_LockMutex(lock); + ... + condition = true; + ... + SDL_CondSignal(cond); + SDL_UnlockMutex(lock); + */ +extern "C" +int +SDL_CondWaitTimeout(SDL_cond * cond, SDL_mutex * mutex, Uint32 ms) +{ + if (!cond) { + SDL_SetError("Passed a NULL condition variable"); + return -1; + } + + if (!mutex) { + SDL_SetError("Passed a NULL mutex variable"); + return -1; + } + + try { + std::unique_lock<std::recursive_mutex> cpp_lock(mutex->cpp_mutex, std::adopt_lock_t()); + if (ms == SDL_MUTEX_MAXWAIT) { + cond->cpp_cond.wait( + cpp_lock + ); + cpp_lock.release(); + return 0; + } else { + auto wait_result = cond->cpp_cond.wait_for( + cpp_lock, + std::chrono::duration<Uint32, std::milli>(ms) + ); + cpp_lock.release(); + if (wait_result == std::cv_status::timeout) { + return SDL_MUTEX_TIMEDOUT; + } else { + return 0; + } + } + } catch (std::system_error & ex) { + SDL_SetError("unable to wait on a C++ condition variable: code=%d; %s", ex.code(), ex.what()); + return -1; + } +} + +/* Wait on the condition variable forever */ +extern "C" +int +SDL_CondWait(SDL_cond * cond, SDL_mutex * mutex) +{ + return SDL_CondWaitTimeout(cond, mutex, SDL_MUTEX_MAXWAIT); +} + +/* vi: set ts=4 sw=4 expandtab: */ |