本文整理汇总了C++中EventableDescriptor::SelectForRead方法的典型用法代码示例。如果您正苦于以下问题：C++ EventableDescriptor::SelectForRead方法的具体用法？C++ EventableDescriptor::SelectForRead怎么用？C++ EventableDescriptor::SelectForRead使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类EventableDescriptor的用法示例。
在下文中一共展示了EventableDescriptor::SelectForRead方法的1个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: _RunSelectOnce
bool EventMachine_t::_RunSelectOnce()
{
// Crank the event machine once.
// If there are no descriptors to process, then sleep
// for a few hundred mills to avoid busy-looping.
// Return T/F to indicate whether we should continue.
// This is based on a select loop. Alternately provide epoll
// if we know we're running on a 2.6 kernel.
// epoll will be effective if we provide it as an alternative,
// however it has the same problem interoperating with Ruby
// threads that select does.
//cerr << "X";
/* This protection is now obsolete, because we will ALWAYS
* have at least one descriptor (the loop-breaker) to read.
*/
/*
if (Descriptors.size() == 0) {
#ifdef OS_UNIX
timeval tv = {0, 200 * 1000};
EmSelect (0, NULL, NULL, NULL, &tv);
return true;
#endif
#ifdef OS_WIN32
Sleep (200);
return true;
#endif
}
*/
SelectData_t SelectData;
/*
fd_set fdreads, fdwrites;
FD_ZERO (&fdreads);
FD_ZERO (&fdwrites);
int maxsocket = 0;
*/
// Always read the loop-breaker reader.
// Changed 23Aug06, provisionally implemented for Windows with a UDP socket
// running on localhost with a randomly-chosen port. (*Puke*)
// Windows has a version of the Unix pipe() library function, but it doesn't
// give you back descriptors that are selectable.
FD_SET (LoopBreakerReader, &(SelectData.fdreads));
if (SelectData.maxsocket < LoopBreakerReader)
SelectData.maxsocket = LoopBreakerReader;
// prepare the sockets for reading and writing
size_t i;
for (i = 0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
int sd = ed->GetSocket();
assert (sd != INVALID_SOCKET);
if (ed->SelectForRead())
FD_SET (sd, &(SelectData.fdreads));
if (ed->SelectForWrite())
FD_SET (sd, &(SelectData.fdwrites));
if (SelectData.maxsocket < sd)
SelectData.maxsocket = sd;
}
{ // read and write the sockets
//timeval tv = {1, 0}; // Solaris fails if the microseconds member is >= 1000000.
//timeval tv = Quantum;
SelectData.tv = Quantum;
int s = SelectData._Select();
//rb_thread_blocking_region(xxx,(void*)&SelectData,RB_UBF_DFL,0);
//int s = EmSelect (SelectData.maxsocket+1, &(SelectData.fdreads), &(SelectData.fdwrites), NULL, &(SelectData.tv));
//int s = SelectData.nSockets;
if (s > 0) {
/* Changed 01Jun07. We used to handle the Loop-breaker right here.
* Now we do it AFTER all the regular descriptors. There's an
* incredibly important and subtle reason for this. Code on
* loop breakers is sometimes used to cause the reactor core to
* cycle (for example, to allow outbound network buffers to drain).
* If a loop-breaker handler reschedules itself (say, after determining
* that the write buffers are still too full), then it will execute
* IMMEDIATELY if _ReadLoopBreaker is done here instead of after
* the other descriptors are processed. That defeats the whole purpose.
*/
for (i=0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
int sd = ed->GetSocket();
assert (sd != INVALID_SOCKET);
if (FD_ISSET (sd, &(SelectData.fdwrites)))
ed->Write();
if (FD_ISSET (sd, &(SelectData.fdreads)))
ed->Read();
}
if (FD_ISSET (LoopBreakerReader, &(SelectData.fdreads)))
_ReadLoopBreaker();
//.........这里部分代码省略.........