/* $Id$ */
#include "silcincludes.h"
+#include "silcschedule_i.h"
+
+/* Our "select()" for WIN32. This mimics the behaviour of select() system
+ call. It does not call the Winsock's select() though. Its functions
+ are derived from GLib's g_poll() and from some old Xemacs's sys_select().
+
+ This makes following assumptions, which I don't know whether they
+ are correct or not:
+
+ o SILC_TASK_WRITE is ignored, if set this will return immediately.
+ o If all arguments except timeout are NULL then this will register
+ a timeout with SetTimer and will wait just for Windows messages
+ with WaitMessage.
+ o MsgWaitForMultipleObjects is used to wait all kind of events, this
+ includes SOCKETs and Windows messages.
+ o All Windows messages are dispatched from this function.
+ o The Operating System has Winsock 2.
+
+ References:
+
+ o http://msdn.microsoft.com/library/default.asp?
+ url=/library/en-us/winui/hh/winui/messques_77zk.asp
+ o http://msdn.microsoft.com/library/default.asp?
+ url=/library/en-us/winsock/hh/winsock/apistart_9g1e.asp
+ o http://msdn.microsoft.com/library/default.asp?
+ url=/library/en-us/dnmgmt/html/msdn_getpeek.asp
+ o http://developer.novell.com/support/winsock/doc/toc.htm
-/* XXX This probably does not work at all the way we want. We mostly
- need the scheduler to handle socket connections. The MSDN says the
- WaitForMultipleObjects should not be used for sockets. Instead they
- should be handled through windows messages (Like WSAAsyncSelect) but
- that would require some different approach to this whole thing. Also,
- I don't know whether I could use the Winsock's select()?? Maybe it would
- be possible to use select(), WaitForMultipleObjects and handle the
- windows messages with the PeekMessage() etc... Dunno... Someone who
- knows these things should take a look at this. Also, If it requires
- some more tweaking I can abandon this silc_select() thingy all together
- and move the generic code to unix/ and program the SILC Scheduler
- interface all together as platform specific. It is here just to
- use as match common code as possible... -Pekka */
-
-/* Our "select()" for WIN32. This actually is not the select() and does
- not call Winsock's select() (since it cannot be used for our purposes)
- but mimics the functions of select().
-
- This is taken from the GLib and is the g_poll function in the Glib.
- It has been *heavily* modified to be select() like and fit for SILC. */
-
-int silc_select(int n, fd_set *readfds, fd_set *writefds,
- fd_set *exceptfds, struct timeval *timeout)
+*/
+
+int silc_select(SilcScheduleFd fds, SilcUInt32 fds_count, struct timeval *timeout)
{
HANDLE handles[MAXIMUM_WAIT_OBJECTS];
- DWORD ready;
- int nhandles = 0;
- int timeo, i;
+ DWORD ready, curtime, timeo;
+ int nhandles = 0, i;
+ MSG msg;
- /* Check fd sets (ignoring the exceptfds for now) */
+ if (fds_count > MAXIMUM_WAIT_OBJECTS)
+ fds_count = MAXIMUM_WAIT_OBJECTS;
- if (readfds) {
- for (i = 0; i < n - 1; i++)
- if (FD_ISSET(i, readfds))
- handles[nhandles++] = (HANDLE)i;
- }
+ for (i = 0; i < fds_count; i++) {
+ if (!fds[i].events)
+ continue;
+
+ if (fds[i].events & SILC_TASK_READ)
+ handles[nhandles++] = (HANDLE)fds[i].fd;
+
+ /* If writing then just set the bit and return */
+ if (fds[i].events & SILC_TASK_WRITE) {
+ fds[i].revents = SILC_TASK_WRITE;
+ return 1;
+ }
- if (writefds) {
- /* If write fd is set then we just return */
- for (i = 0; i < n - 1; i++)
- if (FD_ISSET(i, writefds))
- return 1;
+ fds[i].revents = 0;
}
- if (!timeout)
- timeo = INFINITE;
- else
- timeo = (timeout.tv_sec * 1000) + (timeout.tv_usec / 1000);
+ timeo = (timeout ? (timeout->tv_sec * 1000) + (timeout->tv_usec / 1000) :
+ INFINITE);
+
+ /* If we have nothing to wait and timeout is set then register a timeout
+ and wait just for windows messages. */
+ if (nhandles == 0 && timeout) {
+ UINT timer = SetTimer(NULL, 0, timeo, NULL);
+ curtime = GetTickCount();
+ while (timer) {
+ WaitMessage();
+
+ while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
+ if (msg.message == WM_TIMER) {
+ KillTimer(NULL, timer);
+ return 0;
+ }
+ TranslateMessage(&msg);
+ DispatchMessage(&msg);
+ }
+
+ KillTimer(NULL, timer);
+ if (timeo != INFINITE) {
+ timeo -= GetTickCount() - curtime;
+ if (timeo < 0)
+ timeo = 0;
+ }
+ timer = SetTimer(NULL, 0, timeo, NULL);
+ }
+ }
retry:
- if (nhandles == 0)
- return -1;
- else
- ready = WaitForMultipleObjects(nhandles, handles, FALSE, timeo,
- QS_ALLINPUT);
+ curtime = GetTickCount();
+ ready = MsgWaitForMultipleObjects(nhandles, handles, FALSE, timeo,
+ QS_ALLINPUT);
if (ready == WAIT_FAILED) {
+ /* Wait failed with error */
SILC_LOG_WARNING(("WaitForMultipleObjects() failed"));
return -1;
+ } else if (ready >= WAIT_ABANDONED_0 &&
+ ready < WAIT_ABANDONED_0 + nhandles) {
+ /* Signal abandoned */
+ SILC_LOG_WARNING(("WaitForMultipleObjects() failed (ABANDONED)"));
+ return -1;
} else if (ready == WAIT_TIMEOUT) {
+ /* Timeout */
return 0;
} else if (ready == WAIT_OBJECT_0 + nhandles) {
- /* For Windows messages. The MSDN online says that if the application
+ /* Windows messages. The MSDN online says that if the application
creates a window then its main loop (and we're assuming that
it is our SILC Scheduler) must handle the Windows messages, so do
- it here as the MSDN suggests. -Pekka */
- /* For reference: http://msdn.microsoft.com/library/default.asp?
- url=/library/en-us/winui/hh/winui/messques_77zk.asp */
- MSG msg;
-
+ it here as the MSDN suggests. */
while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
- /* Bad thing is that I don't know what to return, since actually
- nothing for us happened. So, make another try with the waiting
- and do not return. This of course may fuck up the timeouts! */
- goto retry;
- } else if (ready >= WAIT_OBJECT_0 && ready < WAIT_OBJECT_0 + nhandles &&
- readfds) {
- for (i = 0; i < n - 1; i++) {
- if (ready - WAIT_OBJECT_0 != i)
- FD_CLR(i, readfds);
+ /* If timeout is set then we must update the timeout since we won't
+ return and we will give the wait another try. */
+ if (timeo != INFINITE) {
+ timeo -= GetTickCount() - curtime;
+ if (timeo < 0)
+ timeo = 0;
}
- /* Always one entry in the fd set. */
- return 1;
+ /* Give the wait another try */
+ goto retry;
+ } else if (ready >= WAIT_OBJECT_0 && ready < WAIT_OBJECT_0 + nhandles) {
+ /* Some other event, like SOCKET or something. */
+
+ /* Go through all fds even though only one was set. This is to avoid
+ starvation of high numbered fds. */
+ ready -= WAIT_OBJECT_0;
+ do {
+ for (i = 0; i < fds_count; i++) {
+ if (!fds[i].events)
+ continue;
+
+ if (fds[i].fd == (int)handles[ready]) {
+ fds[i].revents |= SILC_TASK_READ;
+ break;
+ }
+ }
+
+ /* Check the status of the next handle and set its fd to the fd
+ set if data is available. */
+ while (++ready < fds_count)
+ if (WaitForSingleObject(handles[ready], 0) == WAIT_OBJECT_0)
+ break;
+ } while (ready < fds_count);
+
+ return i + 1;
}
return -1;
}
+
+#ifdef SILC_THREADS
+
+/* Internal wakeup context. */
+typedef struct {
+ HANDLE wakeup_sema;
+ SilcTask wakeup_task;
+} *SilcWin32Wakeup;
+
+SILC_TASK_CALLBACK(silc_schedule_wakeup_cb)
+{
+ /* Nothing */
+}
+
+#endif /* SILC_THREADS */
+
+/* Initializes the wakeup of the scheduler. In multi-threaded environment
+ the scheduler needs to be wakenup when tasks are added or removed from
+ the task queues. This will initialize the wakeup for the scheduler.
+ Any tasks that needs to be registered must be registered to the `queue'.
+ It is guaranteed that the scheduler will automatically free any
+ registered tasks in this queue. This is system specific routine. */
+
+void *silc_schedule_wakeup_init(SilcSchedule schedule)
+{
+#ifdef SILC_THREADS
+ SilcWin32Wakeup wakeup;
+
+ wakeup = silc_calloc(1, sizeof(*wakeup));
+
+ wakeup->wakeup_sema = CreateSemaphore(NULL, 0, 100, NULL);
+ if (!wakeup->wakeup_sema) {
+ silc_free(wakeup);
+ return NULL;
+ }
+
+ wakeup->wakeup_task =
+ silc_schedule_task_add(schedule, (int)wakeup->wakeup_sema,
+ silc_schedule_wakeup_cb, wakeup,
+ 0, 0, SILC_TASK_FD,
+ SILC_TASK_PRI_NORMAL);
+ if (!wakeup->wakeup_task) {
+ CloseHandle(wakeup->wakeup_sema);
+ silc_free(wakeup);
+ return NULL;
+ }
+
+ return (void *)wakeup;
+#else
+ return NULL;
+#endif
+}
+
+/* Uninitializes the system specific wakeup. */
+
+void silc_schedule_wakeup_uninit(void *context)
+{
+#ifdef SILC_THREADS
+ SilcWin32Wakeup wakeup = (SilcWin32Wakeup)context;
+
+ if (!wakeup)
+ return;
+
+ CloseHandle(wakeup->wakeup_sema);
+ silc_free(wakeup);
+#endif
+}
+
+/* Wakes up the scheduler */
+
+void silc_schedule_wakeup_internal(void *context)
+{
+#ifdef SILC_THREADS
+ SilcWin32Wakeup wakeup = (SilcWin32Wakeup)context;
+
+ if (!wakeup)
+ return;
+
+ ReleaseSemaphore(wakeup->wakeup_sema, 1, NULL);
+#endif
+}