在信号处理程序中使用
std::condition_variable::notify_one是否安全？例：
enum State {
DoNot,Do,};
State state;
std::mutex mutex;
// worker thread
std::thread th = std::thread([]()
{
std::unique_lock<std::mutex> lc(mutex);
cv.wait(lc,[]() { return state; });
});
//signal handler
void handler(int sig)
{
if (sig == SOME_SIG)
{
std::unique_lock<std::mutex> lc(mutex);
state = Do;
cv.notify_one();
}
}
解决方法
C 14标准草案
N4296说：
[support.runtime]/10 The common subset of the C and C++ languages consists of all declarations,definitions,and expressions
that may appear in a well formed C++ program and also in a conforming C program. A POF (“plain old
function”) is a function that uses only features from this common subset,and that does not directly or indirectly use any function that is not a POF,except that it may use plain lock-free atomic operations… The behavior of any
function other than a POF used as a signal handler in a C++ program is implementation-defined.
强调我的.
