2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2007, Dave Pare, Jeff Bailey, Thomas Ruschak,
4 * Ken Stevens, Steve McClure
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * See files README, COPYING and CREDITS in the root of the source
23 * tree for related information and legal notices. It is expected
24 * that future projects/authors will amend these files as needed.
28 * ntthread.c: Interface from Empire threads to Windows NT threads
30 * Known contributors to this file:
33 * Ron Koenderink, 2004-2007
37 * EMPTHREADs for Windows NT.
39 * Actually, threads for any Win32 platform, like Win95, Win98, WinCE,
40 * and whatever other toy OSs are in our future from Microsoft.
42 * WIN32 has a full pre-emptive threading environment. But Empire can
43 * not handle pre-emptive threading. Thus, we will use the threads,
44 * but limit the preemption using a Mutex.
53 #include <sys/types.h>
59 /* Note: unistd.h(posixio.c) is not thread-safe.
60 * It may be used *only* while holding hThreadMutex.
64 #include "empthread.h"
65 #include "prototypes.h"
68 #define loc_MIN_THREAD_STACK 16384
70 /************************
75 /* The thread name, passed in at create time. */
78 /* True if this is the main line, and not a real thread. */
81 /* The user data passed in at create time. */
84 /* True if this thread has been killed. */
87 /* The entry function for the thread. */
88 void (*pfnEntry) (void *);
90 /* The system thread ID. */
91 unsigned long ulThreadID;
93 /* An Mutex that the thread will wait/sleep on. */
98 /************************
102 * must hold at function call, return, sleep
103 * and resume from sleep.
115 * if read-locked without writers contending:
121 * if read-locked with writers contending:
124 * nwrite > 0 #writers blocked
130 * nwrite > 0 #writers blocked + 1
133 * To ensure consistency, state normally changes only while the
134 * thread changing it holds hThreadMutex.
138 char name[17]; /* The thread name, passed in at create time. */
139 HANDLE can_read; /* Manual event -- allows read locks */
140 HANDLE can_write; /* Auto-reset event -- allows write locks */
141 int nread; /* number of active readers */
142 int nwrite; /* total number of writers (active and waiting) */
145 /* This is the thread exclusion/non-premption mutex. */
146 /* The running thread has this MUTEX, and all others are */
147 /* either blocked on it, or waiting for some OS response. */
148 static HANDLE hThreadMutex;
150 /* This is the thread startup event. */
151 /* We use this to lockstep when we are starting up threads. */
152 static HANDLE hThreadStartEvent;
154 /* This is an event used to wakeup the main thread */
155 /* to start the shutdown sequence. */
156 static HANDLE hShutdownEvent;
158 /* The Thread Local Storage index. We store the pThread pointer */
159 /* for each thread at this index. */
160 static DWORD dwTLSIndex;
162 /* The current running thread. */
163 static empth_t *pCurThread;
166 static unsigned long ulTickAtStart;
168 /* Pointer out to global context. "player". */
169 /* From empth_init parameter. */
170 static void **ppvUserData;
172 /* Global flags. From empth_init parameter. */
173 static int global_flags;
176 /************************
179 * Print out the current thread's status??
182 loc_debug(const char *pszFmt, ...)
185 unsigned long ulCurTick;
186 unsigned long ulRunTick;
187 unsigned long ulMs, ulSec, ulMin, ulHr;
188 empth_t *pThread = TlsGetValue(dwTLSIndex);
191 if ((global_flags & EMPTH_PRINT) != 0) {
193 /* Ticks are in milliseconds */
194 ulCurTick = GetTickCount();
196 ulRunTick = ulCurTick - ulTickAtStart;
197 ulMs = ulRunTick % 1000L;
198 ulSec = (ulRunTick / 1000L) % 60L;
199 ulMin = (ulRunTick / (60L * 1000L)) % 60L;
200 ulHr = (ulRunTick / (60L * 60L * 1000L));
202 va_start(vaList, pszFmt);
203 vsprintf(buf, pszFmt, vaList);
207 printf("%ld:%02ld:%02ld.%03ld %17s: %s\n",
208 ulHr, ulMin, ulSec, ulMs, pThread->szName, buf);
210 printf("%ld:%02ld:%02ld.%03ld %17s: %s\n",
211 ulHr, ulMin, ulSec, ulMs, "UNKNOWN", buf);
217 /************************
221 loc_FreeThreadInfo(empth_t *pThread)
224 if (pThread->hThreadEvent)
225 CloseHandle(pThread->hThreadEvent);
226 memset(pThread, 0, sizeof(*pThread));
231 /************************
234 * This thread wants to run.
235 * When this function returns, the globals are set to this thread
236 * info, and the thread owns the MUTEX.
239 loc_RunThisThread(HANDLE hWaitObject)
241 HANDLE hWaitObjects[2];
243 empth_t *pThread = TlsGetValue(dwTLSIndex);
245 if (pThread->bKilled) {
246 if (!pThread->bMainThread) {
247 TlsSetValue(dwTLSIndex, NULL);
248 loc_FreeThreadInfo(pThread);
253 hWaitObjects[0] = hThreadMutex;
254 hWaitObjects[1] = hWaitObject;
256 WaitForMultipleObjects(hWaitObject ? 2 : 1, hWaitObjects,
260 /* Set the globals to this thread. */
261 *ppvUserData = pThread->pvUserData;
263 pCurThread = pThread;
265 /* Hmm, a problem, eh? */
266 logerror("RunThisThread, someone already running.");
270 /************************
271 * loc_BlockThisThread
273 * This thread was running. It no longer wants to.
276 loc_BlockThisThread(void)
278 empth_t *pThread = TlsGetValue(dwTLSIndex);
280 if (pCurThread == pThread) {
281 /* Reset the globals back to original */
286 /* Release the MUTEX */
287 ReleaseMutex(hThreadMutex);
289 /* Hmm, this thread was not the running one. */
290 logerror("BlockThisThread, not running.");
294 /************************
297 * Ctrl-C, Ctrl-Break, Window-Closure, User-Logging-Off or
298 * System-Shutdown will initiate a shutdown.
299 * This is done by calling empth_request_shutdown()
302 loc_Exit_Handler(DWORD fdwCtrlType)
304 switch (fdwCtrlType) {
306 case CTRL_CLOSE_EVENT:
307 case CTRL_BREAK_EVENT:
308 case CTRL_LOGOFF_EVENT:
309 case CTRL_SHUTDOWN_EVENT:
310 empth_request_shutdown();
317 /************************
320 * This is the main line of each thread.
321 * This is really a static local func....
322 * Note: As the POSIX compatibility layer is not thread safe
323 * this function can not open or create any files or sockets until
324 * loc_RunThisThread() is called
327 empth_threadMain(void *pvData)
331 empth_t *pThread = pvData;
337 /* Store pThread on this thread. */
338 TlsSetValue(dwTLSIndex, pvData);
340 /* Get the ID of the thread. */
341 pThread->ulThreadID = GetCurrentThreadId();
343 /* Signal that the thread has started. */
344 SetEvent(hThreadStartEvent);
347 * seed the rand() function
348 * In WIN32, each thread has seed
351 srandom(now ^ (unsigned)pThread);
353 /* Switch to this thread context */
354 loc_RunThisThread(NULL);
356 /* Run the thread. */
357 if (pThread->pfnEntry)
358 pThread->pfnEntry(pThread->pvUserData);
360 /* Kill the thread. */
364 /************************
367 * Initialize the thread environment.
369 * This is called from the program main line.
372 empth_init(void **ctx_ptr, int flags)
374 empth_t *pThread = NULL;
376 ulTickAtStart = GetTickCount();
377 ppvUserData = ctx_ptr;
378 global_flags = flags;
379 dwTLSIndex = TlsAlloc();
381 /* Create the thread mutex. */
382 /* Initally unowned. */
383 hThreadMutex = CreateMutex(NULL, FALSE, NULL);
385 logerror("Failed to create mutex %lu", GetLastError());
389 /* Create the thread start event. */
390 /* Automatic state reset. */
391 hThreadStartEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
392 if (!hThreadStartEvent) {
393 logerror("Failed to create start event %lu", GetLastError());
397 /* Create the shutdown event for the main thread. */
399 hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
400 if (!hShutdownEvent) {
401 logerror("Failed to create shutdown event %lu", GetLastError());
404 SetConsoleCtrlHandler((PHANDLER_ROUTINE)loc_Exit_Handler, TRUE);
406 /* Create the global Thread context. */
407 pThread = malloc(sizeof(*pThread));
409 logerror("not enough memory to create main thread.");
412 memset(pThread, 0, sizeof(*pThread));
414 strncpy(pThread->szName, "Main", sizeof(pThread->szName) - 1);
415 pThread->ulThreadID = GetCurrentThreadId();
416 pThread->bMainThread = TRUE;
418 TlsSetValue(dwTLSIndex, pThread);
420 /* Make this the running thread. */
421 loc_RunThisThread(NULL);
423 logerror("NT pthreads initialized");
428 /************************
431 * Create a new thread.
433 * entry - entry point function for thread.
435 * flags - debug control.
436 * LWP_STACKCHECK - not needed
437 * name - name of the thread, for debug.
438 * ud - "user data". The "ctx_ptr" gets this value
439 * when the thread is active.
440 * It is also passed to the entry function...
443 empth_create(void (*entry)(void *), int size, int flags,
444 char *name, void *ud)
446 empth_t *pThread = NULL;
448 loc_debug("creating new thread %s", name);
450 pThread = malloc(sizeof(*pThread));
452 logerror("not enough memory to create thread %s", name);
455 memset(pThread, 0, sizeof(*pThread));
457 strncpy(pThread->szName, name, sizeof(pThread->szName) - 1);
458 pThread->pvUserData = ud;
459 pThread->pfnEntry = entry;
460 pThread->bMainThread = FALSE;
462 /* Create thread event, auto reset. */
463 pThread->hThreadEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
465 if (size < loc_MIN_THREAD_STACK)
466 size = loc_MIN_THREAD_STACK;
468 pThread->ulThreadID = _beginthread(empth_threadMain, size, pThread);
469 if (pThread->ulThreadID == 1L) {
470 logerror("can not create thread: %s: %s", name, strerror(errno));
474 loc_debug("new thread id is %ld", pThread->ulThreadID);
480 loc_FreeThreadInfo(pThread);
486 /************************
492 empth_t *pThread = TlsGetValue(dwTLSIndex);
497 /************************
503 empth_t *pThread = TlsGetValue(dwTLSIndex);
505 loc_debug("empth_exit");
506 loc_BlockThisThread();
508 TlsSetValue(dwTLSIndex, NULL);
509 loc_FreeThreadInfo(pThread);
513 /************************
516 * Yield processing to another thread.
521 loc_BlockThisThread();
522 loc_RunThisThread(NULL);
525 /************************
528 * Kill off the thread.
531 empth_terminate(empth_t *pThread)
533 loc_debug("killing thread %s", pThread->szName);
534 pThread->bKilled = TRUE;
536 SetEvent(pThread->hThreadEvent);
539 /************************
542 * Do a select on the given file.
545 * This would be one of the main functions used within gen\io.c
548 empth_select(int fd, int flags)
551 WSAEVENT hEventObject[2];
552 empth_t *pThread = TlsGetValue(dwTLSIndex);
554 loc_debug("%s select on %d",
555 flags == EMPTH_FD_READ ? "read" : "write", fd);
556 loc_BlockThisThread();
558 hEventObject[0] = WSACreateEvent();
559 hEventObject[1] = pThread->hThreadEvent;
561 handle = posix_fd2socket(fd);
562 CANT_HAPPEN(handle < 0);
564 if (flags == EMPTH_FD_READ)
565 WSAEventSelect(handle, hEventObject[0], FD_READ | FD_ACCEPT | FD_CLOSE);
566 else if (flags == EMPTH_FD_WRITE)
567 WSAEventSelect(handle, hEventObject[0], FD_WRITE | FD_CLOSE);
569 logerror("bad flag %d passed to empth_select", flags);
573 WSAWaitForMultipleEvents(2, hEventObject, FALSE, WSA_INFINITE, FALSE);
575 WSAEventSelect(handle, hEventObject[0], 0);
577 WSACloseEvent(hEventObject[0]);
579 loc_RunThisThread(NULL);
582 /************************
585 * Wake up the specified thread.
588 empth_wakeup(empth_t *pThread)
590 loc_debug("waking up thread %s", pThread->szName);
592 /* Let it run if it is blocked... */
593 SetEvent(pThread->hThreadEvent);
596 /************************
599 * Put the given thread to sleep...
602 empth_sleep(time_t until)
605 empth_t *pThread = TlsGetValue(dwTLSIndex);
608 while (!iReturn && ((lSec = until - time(0)) > 0)) {
609 loc_BlockThisThread();
610 loc_debug("going to sleep %ld sec", lSec);
612 if (WaitForSingleObject(pThread->hThreadEvent, lSec * 1000L) !=
616 loc_debug("sleep done. Waiting to run.");
617 loc_RunThisThread(NULL);
622 /************************
623 * empth_request_shutdown
625 * This wakes up empth_wait_for_signal() so shutdown can proceed.
626 * This is done by signalling hShutdownEvent.
629 empth_request_shutdown(void)
631 SetEvent(hShutdownEvent);
635 empth_wait_for_signal(void)
637 loc_BlockThisThread();
638 loc_RunThisThread(hShutdownEvent);
643 empth_rwlock_create(char *name)
645 empth_rwlock_t *rwlock;
647 rwlock = malloc(sizeof(*rwlock));
651 memset(rwlock, 0, sizeof(*rwlock));
652 strncpy(rwlock->name, name, sizeof(rwlock->name) - 1);
654 if ((rwlock->can_read = CreateEvent(NULL, TRUE, TRUE, NULL)) == NULL) {
655 logerror("rwlock_create: failed to create reader event %s at %s:%d",
656 name, __FILE__, __LINE__);
661 if ((rwlock->can_write = CreateEvent(NULL, FALSE, TRUE, NULL)) == NULL) {
662 logerror("rwlock_create: failed to create writer event %s at %s:%d",
663 name, __FILE__, __LINE__);
664 CloseHandle(rwlock->can_read);
672 empth_rwlock_destroy(empth_rwlock_t *rwlock)
674 if (CANT_HAPPEN(rwlock->nread || rwlock->nwrite))
676 CloseHandle(rwlock->can_read);
677 CloseHandle(rwlock->can_write);
682 empth_rwlock_wrlock(empth_rwlock_t *rwlock)
684 /* block any new readers */
685 ResetEvent(rwlock->can_read);
687 loc_BlockThisThread();
688 loc_RunThisThread(rwlock->can_write);
689 CANT_HAPPEN(rwlock->nread != 0);
693 empth_rwlock_rdlock(empth_rwlock_t *rwlock)
695 loc_BlockThisThread();
696 loc_RunThisThread(rwlock->can_read);
697 ResetEvent(rwlock->can_write);
702 empth_rwlock_unlock(empth_rwlock_t *rwlock)
704 if (CANT_HAPPEN(!rwlock->nread && !rwlock->nwrite))
706 if (rwlock->nread) { /* holding read lock */
708 if (rwlock->nread == 0)
709 SetEvent(rwlock->can_write);
712 SetEvent(rwlock->can_write);
714 if (rwlock->nwrite == 0)
715 SetEvent(rwlock->can_read);