int poll(struct pollfd *fds, nfds_t nfds, int timeout)
{
DebugPrint(dbg_hook, "hook poll. %s coroutine.", g_Scheduler.IsCoroutine() ? "In" : "Not in");
if (!g_Scheduler.IsCoroutine())
return poll_f(fds, nfds, timeout);
if (timeout == 0)
return poll_f(fds, nfds, timeout);
Task* tk = g_Scheduler.GetCurrentTask();
uint32_t timer_id = 0;
if (timeout != -1) {
std::chrono::milliseconds duration{timeout};
tk->IncrementRef(); // timer use ref.
timer_id = g_Scheduler.ExpireAt(duration, [=]{
g_Scheduler.IOBlockCancel(tk);
tk->DecrementRef(); // timer use ref.
});
}
std::vector<FdStruct> fdsts;
for (nfds_t i = 0; i < nfds; ++i) {
fdsts.emplace_back();
fdsts.back().fd = fds[i].fd;
fdsts.back().event = PollEvent2Epoll(fds[i].events);
}
// add into epoll, and switch other context.
g_Scheduler.IOBlockSwitch(fdsts);
bool is_timeout = false; // 是否超时
if (timer_id) {
is_timeout = true;
if (g_Scheduler.CancelTimer(timer_id)) {
tk->DecrementRef(); // timer use ref.
is_timeout = false;
}
}
if (tk->wait_successful_ == 0) {
if (is_timeout)
return 0;
else
return poll_f(fds, nfds, 0);
}
int n = 0;
for (int i = 0; i < (int)tk->wait_fds_.size(); ++i)
{
fds[i].revents = EpollEvent2Poll(tk->wait_fds_[i].epoll_ptr.revent);
if (fds[i].revents) ++n;
}
assert(n == (int)tk->wait_successful_);
return n;
}
ssize_t read_write_mode(int fd, OriginF fn, const char* hook_fn_name, uint32_t event, int timeout_so, Args && ... args)
{
DebugPrint(dbg_hook, "hook %s. %s coroutine.", hook_fn_name, g_Scheduler.IsCoroutine() ? "In" : "Not in");
if (!g_Scheduler.IsCoroutine()) {
return fn(fd, std::forward<Args>(args)...);
} else {
int flags = fcntl(fd, F_GETFL, 0);
if (flags & O_NONBLOCK)
return fn(fd, std::forward<Args>(args)...);
if (-1 == fcntl(fd, F_SETFL, flags | O_NONBLOCK))
return fn(fd, std::forward<Args>(args)...);
ssize_t n = fn(fd, std::forward<Args>(args)...);
if (n == -1 && (errno == EAGAIN || errno == EWOULDBLOCK)) {
// get timeout option.
Task* tk = g_Scheduler.GetCurrentTask();
uint64_t timer_id = 0;
struct timeval timeout;
socklen_t timeout_blen = sizeof(timeout);
if (0 == getsockopt(fd, SOL_SOCKET, timeout_so, &timeout, &timeout_blen)) {
if (timeout.tv_sec > 0 || timeout.tv_usec > 0) {
std::chrono::milliseconds duration{timeout.tv_sec * 1000 +
timeout.tv_usec / 1000};
DebugPrint(dbg_hook, "hook task(%s) %s timeout=%dms. fd=%d",
g_Scheduler.GetCurrentTaskDebugInfo(), hook_fn_name, (int)duration.count(), fd);
tk->IncrementRef(); // timer use ref.
timer_id = g_Scheduler.ExpireAt(duration, [=]{
g_Scheduler.IOBlockCancel(tk);
tk->DecrementRef(); // timer use ref.
});
}
}
// add into epoll, and switch other context.
g_Scheduler.IOBlockSwitch(fd, event);
bool is_timeout = false;
if (timer_id) {
is_timeout = true;
if (g_Scheduler.CancelTimer(timer_id)) {
is_timeout = false;
tk->DecrementRef(); // timer use ref.
}
}
if (tk->wait_successful_ == 0) {
if (is_timeout) {
fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
errno = EAGAIN;
return -1;
} else {
fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
return fn(fd, std::forward<Args>(args)...);
}
}
DebugPrint(dbg_hook, "continue task(%s) %s. fd=%d", g_Scheduler.GetCurrentTaskDebugInfo(), hook_fn_name, fd);
n = fn(fd, std::forward<Args>(args)...);
} else {
DebugPrint(dbg_hook, "task(%s) syscall(%s) completed immediately. fd=%d",
g_Scheduler.GetCurrentTaskDebugInfo(), hook_fn_name, fd);
}
int e = errno;
fcntl(fd, F_SETFL, flags & ~O_NONBLOCK);
errno = e;
return n;
}
}
