2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2008, 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;
175 static void loc_debug(const char *, ...) ATTRIBUTE((format(printf, 1, 2)));
177 /************************
180 * Print out the current thread's status??
183 loc_debug(const char *pszFmt, ...)
186 unsigned long ulCurTick;
187 unsigned long ulRunTick;
188 unsigned long ulMs, ulSec, ulMin, ulHr;
189 empth_t *pThread = TlsGetValue(dwTLSIndex);
192 if ((global_flags & EMPTH_PRINT) != 0) {
194 /* Ticks are in milliseconds */
195 ulCurTick = GetTickCount();
197 ulRunTick = ulCurTick - ulTickAtStart;
198 ulMs = ulRunTick % 1000L;
199 ulSec = (ulRunTick / 1000L) % 60L;
200 ulMin = (ulRunTick / (60L * 1000L)) % 60L;
201 ulHr = (ulRunTick / (60L * 60L * 1000L));
203 va_start(vaList, pszFmt);
204 vsprintf(buf, pszFmt, vaList);
208 printf("%ld:%02ld:%02ld.%03ld %17s: %s\n",
209 ulHr, ulMin, ulSec, ulMs, pThread->szName, buf);
211 printf("%ld:%02ld:%02ld.%03ld %17s: %s\n",
212 ulHr, ulMin, ulSec, ulMs, "UNKNOWN", buf);
218 /************************
222 loc_FreeThreadInfo(empth_t *pThread)
225 if (pThread->hThreadEvent)
226 CloseHandle(pThread->hThreadEvent);
227 memset(pThread, 0, sizeof(*pThread));
232 /************************
235 * This thread wants to run.
236 * When this function returns, the globals are set to this thread
237 * info, and the thread owns the MUTEX.
240 loc_RunThisThread(HANDLE hWaitObject)
242 HANDLE hWaitObjects[2];
244 empth_t *pThread = TlsGetValue(dwTLSIndex);
246 if (pThread->bKilled) {
247 if (!pThread->bMainThread) {
248 TlsSetValue(dwTLSIndex, NULL);
249 loc_FreeThreadInfo(pThread);
254 hWaitObjects[0] = hThreadMutex;
255 hWaitObjects[1] = hWaitObject;
257 WaitForMultipleObjects(hWaitObject ? 2 : 1, hWaitObjects,
261 /* Set the globals to this thread. */
262 *ppvUserData = pThread->pvUserData;
264 pCurThread = pThread;
266 /* Hmm, a problem, eh? */
267 logerror("RunThisThread, someone already running.");
271 /************************
272 * loc_BlockThisThread
274 * This thread was running. It no longer wants to.
277 loc_BlockThisThread(void)
279 empth_t *pThread = TlsGetValue(dwTLSIndex);
281 if (pCurThread == pThread) {
282 /* Reset the globals back to original */
287 /* Release the MUTEX */
288 ReleaseMutex(hThreadMutex);
290 /* Hmm, this thread was not the running one. */
291 logerror("BlockThisThread, not running.");
295 /************************
298 * Ctrl-C, Ctrl-Break, Window-Closure, User-Logging-Off or
299 * System-Shutdown will initiate a shutdown.
300 * This is done by calling empth_request_shutdown()
303 loc_Exit_Handler(DWORD fdwCtrlType)
305 switch (fdwCtrlType) {
307 case CTRL_CLOSE_EVENT:
308 case CTRL_BREAK_EVENT:
309 case CTRL_LOGOFF_EVENT:
310 case CTRL_SHUTDOWN_EVENT:
311 empth_request_shutdown();
318 /************************
321 * This is the main line of each thread.
322 * This is really a static local func....
323 * Note: As the POSIX compatibility layer is not thread safe
324 * this function can not open or create any files or sockets until
325 * loc_RunThisThread() is called
328 empth_threadMain(void *pvData)
330 empth_t *pThread = pvData;
336 /* Store pThread on this thread. */
337 TlsSetValue(dwTLSIndex, pvData);
339 /* Get the ID of the thread. */
340 pThread->ulThreadID = GetCurrentThreadId();
342 /* Signal that the thread has started. */
343 SetEvent(hThreadStartEvent);
345 /* Switch to this thread context */
346 loc_RunThisThread(NULL);
348 /* Run the thread. */
349 if (pThread->pfnEntry)
350 pThread->pfnEntry(pThread->pvUserData);
352 /* Kill the thread. */
356 /************************
359 * Initialize the thread environment.
361 * This is called from the program main line.
364 empth_init(void **ctx_ptr, int flags)
366 empth_t *pThread = NULL;
368 ulTickAtStart = GetTickCount();
369 ppvUserData = ctx_ptr;
370 global_flags = flags;
371 dwTLSIndex = TlsAlloc();
373 /* Create the thread mutex. */
374 /* Initally unowned. */
375 hThreadMutex = CreateMutex(NULL, FALSE, NULL);
377 logerror("Failed to create mutex %lu", GetLastError());
381 /* Create the thread start event. */
382 /* Automatic state reset. */
383 hThreadStartEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
384 if (!hThreadStartEvent) {
385 logerror("Failed to create start event %lu", GetLastError());
389 /* Create the shutdown event for the main thread. */
391 hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
392 if (!hShutdownEvent) {
393 logerror("Failed to create shutdown event %lu", GetLastError());
396 SetConsoleCtrlHandler(loc_Exit_Handler, TRUE);
398 /* Create the global Thread context. */
399 pThread = malloc(sizeof(*pThread));
401 logerror("not enough memory to create main thread.");
404 memset(pThread, 0, sizeof(*pThread));
406 strncpy(pThread->szName, "Main", sizeof(pThread->szName) - 1);
407 pThread->ulThreadID = GetCurrentThreadId();
408 pThread->bMainThread = TRUE;
410 TlsSetValue(dwTLSIndex, pThread);
412 /* Make this the running thread. */
413 loc_RunThisThread(NULL);
415 logerror("NT pthreads initialized");
420 /************************
423 * Create a new thread.
425 * entry - entry point function for thread.
427 * flags - debug control.
428 * LWP_STACKCHECK - not needed
429 * name - name of the thread, for debug.
430 * ud - "user data". The "ctx_ptr" gets this value
431 * when the thread is active.
432 * It is also passed to the entry function...
435 empth_create(void (*entry)(void *), int size, int flags,
436 char *name, void *ud)
438 empth_t *pThread = NULL;
440 loc_debug("creating new thread %s", name);
442 pThread = malloc(sizeof(*pThread));
444 logerror("not enough memory to create thread %s", name);
447 memset(pThread, 0, sizeof(*pThread));
449 strncpy(pThread->szName, name, sizeof(pThread->szName) - 1);
450 pThread->pvUserData = ud;
451 pThread->pfnEntry = entry;
452 pThread->bMainThread = FALSE;
454 /* Create thread event, auto reset. */
455 pThread->hThreadEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
457 if (size < loc_MIN_THREAD_STACK)
458 size = loc_MIN_THREAD_STACK;
460 pThread->ulThreadID = _beginthread(empth_threadMain, size, pThread);
461 if (pThread->ulThreadID == 1L) {
462 logerror("can not create thread: %s: %s", name, strerror(errno));
466 loc_debug("new thread id is %ld", pThread->ulThreadID);
472 loc_FreeThreadInfo(pThread);
478 /************************
484 empth_t *pThread = TlsGetValue(dwTLSIndex);
489 /************************
495 empth_t *pThread = TlsGetValue(dwTLSIndex);
497 loc_debug("empth_exit");
498 loc_BlockThisThread();
500 TlsSetValue(dwTLSIndex, NULL);
501 loc_FreeThreadInfo(pThread);
505 /************************
508 * Yield processing to another thread.
513 loc_BlockThisThread();
515 loc_RunThisThread(NULL);
518 /************************
521 * Kill off the thread.
524 empth_terminate(empth_t *pThread)
526 loc_debug("killing thread %s", pThread->szName);
527 pThread->bKilled = TRUE;
529 SetEvent(pThread->hThreadEvent);
532 /************************
535 * Do a select on the given file.
538 * This would be one of the main functions used within gen\io.c
541 empth_select(int fd, int flags)
544 WSAEVENT hEventObject[2];
545 empth_t *pThread = TlsGetValue(dwTLSIndex);
547 loc_debug("%s select on %d",
548 flags == EMPTH_FD_READ ? "read" : "write", fd);
549 loc_BlockThisThread();
551 hEventObject[0] = WSACreateEvent();
552 hEventObject[1] = pThread->hThreadEvent;
554 handle = posix_fd2socket(fd);
555 CANT_HAPPEN(handle < 0);
557 if (flags == EMPTH_FD_READ)
558 WSAEventSelect(handle, hEventObject[0], FD_READ | FD_ACCEPT | FD_CLOSE);
559 else if (flags == EMPTH_FD_WRITE)
560 WSAEventSelect(handle, hEventObject[0], FD_WRITE | FD_CLOSE);
562 logerror("bad flag %d passed to empth_select", flags);
566 WSAWaitForMultipleEvents(2, hEventObject, FALSE, WSA_INFINITE, FALSE);
568 WSAEventSelect(handle, hEventObject[0], 0);
570 WSACloseEvent(hEventObject[0]);
572 loc_RunThisThread(NULL);
575 /************************
578 * Wake up the specified thread.
581 empth_wakeup(empth_t *pThread)
583 loc_debug("waking up thread %s", pThread->szName);
585 /* Let it run if it is blocked... */
586 SetEvent(pThread->hThreadEvent);
589 /************************
592 * Put the given thread to sleep...
595 empth_sleep(time_t until)
598 empth_t *pThread = TlsGetValue(dwTLSIndex);
601 while (!iReturn && ((lSec = until - time(0)) > 0)) {
602 loc_BlockThisThread();
603 loc_debug("going to sleep %ld sec", lSec);
605 if (WaitForSingleObject(pThread->hThreadEvent, lSec * 1000L) !=
609 loc_debug("sleep done. Waiting to run.");
610 loc_RunThisThread(NULL);
615 /************************
616 * empth_request_shutdown
618 * This wakes up empth_wait_for_signal() so shutdown can proceed.
619 * This is done by signalling hShutdownEvent.
622 empth_request_shutdown(void)
624 SetEvent(hShutdownEvent);
628 empth_wait_for_signal(void)
630 loc_BlockThisThread();
631 loc_RunThisThread(hShutdownEvent);
636 empth_rwlock_create(char *name)
638 empth_rwlock_t *rwlock;
640 rwlock = malloc(sizeof(*rwlock));
644 memset(rwlock, 0, sizeof(*rwlock));
645 strncpy(rwlock->name, name, sizeof(rwlock->name) - 1);
647 if ((rwlock->can_read = CreateEvent(NULL, TRUE, TRUE, NULL)) == NULL) {
648 logerror("rwlock_create: failed to create reader event %s at %s:%d",
649 name, __FILE__, __LINE__);
654 if ((rwlock->can_write = CreateEvent(NULL, FALSE, TRUE, NULL)) == NULL) {
655 logerror("rwlock_create: failed to create writer event %s at %s:%d",
656 name, __FILE__, __LINE__);
657 CloseHandle(rwlock->can_read);
665 empth_rwlock_destroy(empth_rwlock_t *rwlock)
667 if (CANT_HAPPEN(rwlock->nread || rwlock->nwrite))
669 CloseHandle(rwlock->can_read);
670 CloseHandle(rwlock->can_write);
675 empth_rwlock_wrlock(empth_rwlock_t *rwlock)
677 /* block any new readers */
678 ResetEvent(rwlock->can_read);
680 loc_BlockThisThread();
681 loc_RunThisThread(rwlock->can_write);
682 CANT_HAPPEN(rwlock->nread != 0);
686 empth_rwlock_rdlock(empth_rwlock_t *rwlock)
688 loc_BlockThisThread();
689 loc_RunThisThread(rwlock->can_read);
690 ResetEvent(rwlock->can_write);
695 empth_rwlock_unlock(empth_rwlock_t *rwlock)
697 if (CANT_HAPPEN(!rwlock->nread && !rwlock->nwrite))
699 if (rwlock->nread) { /* holding read lock */
701 if (rwlock->nread == 0)
702 SetEvent(rwlock->can_write);
705 SetEvent(rwlock->can_write);
707 if (rwlock->nwrite == 0)
708 SetEvent(rwlock->can_read);