2 * Empire - A multi-player, client/server Internet based war game.
3 * Copyright (C) 1986-2006, 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 * pthread.c: Interface from Empire threads to POSIX threads
30 * Known contributors to this file:
33 * Markus Armbruster, 2005
36 /* Required for PTHREAD_STACK_MIN on some systems, e.g. Solaris: */
37 #define _XOPEN_SOURCE 500
46 #include <sys/types.h>
53 #include "empthread.h"
54 #include "prototypes.h"
58 #define EMPTH_KILLED 1
61 char *name; /* thread name */
62 char *desc; /* description */
63 void *ud; /* user data */
64 int state; /* my state */
65 void (*ep)(void *); /* entry point */
66 pthread_t id; /* thread id */
70 pthread_mutex_t mtx_update; /* use it to update count */
73 pthread_mutex_t mtx_sem;
74 pthread_cond_t cnd_sem;
77 /* Thread-specific data key */
78 static pthread_key_t ctx_key;
80 /* Flags that were passed to empth_init() */
81 static int empth_flags;
83 /* Pointer to thread context variable */
87 * Non-preemption mutex.
88 * Empire code outside this file is only executed while holding this
89 * mutex. This makes sure Empire code is never preempted by Empire
92 static pthread_mutex_t mtx_ctxsw;
94 static void empth_status(char *format, ...)
95 ATTRIBUTE((format (printf, 1, 2)));
96 static void empth_alarm(int sig);
99 empth_start(void *arg)
102 struct sigaction act;
104 /* actually it should inherit all this from main but... */
106 sigemptyset(&act.sa_mask);
107 act.sa_handler = shutdwn;
108 sigaction(SIGTERM, &act, NULL);
109 sigaction(SIGINT, &act, NULL);
110 act.sa_handler = panic;
111 sigaction(SIGBUS, &act, NULL);
112 sigaction(SIGSEGV, &act, NULL);
113 sigaction(SIGILL, &act, NULL);
114 sigaction(SIGFPE, &act, NULL);
115 act.sa_handler = SIG_IGN;
116 sigaction(SIGPIPE, &act, NULL);
118 act.sa_handler = empth_alarm;
119 sigaction(SIGALRM, &act, NULL);
121 ctx->id = pthread_self();
122 pthread_setspecific(ctx_key, ctx);
123 pthread_mutex_lock(&mtx_ctxsw);
131 empth_status(char *format, ...)
134 static struct timeval startTime;
140 va_start(ap, format);
141 if (empth_flags & EMPTH_PRINT) {
142 if (startTime.tv_sec == 0)
143 gettimeofday(&startTime, 0);
144 gettimeofday(&tv, 0);
145 sec = tv.tv_sec - startTime.tv_sec;
146 msec = (tv.tv_usec - startTime.tv_usec) / 1000;
151 vsprintf(buf, format, ap);
153 printf("%d:%02d.%03d %17s: %s\n", sec / 60, sec % 60, msec / 10,
162 empth_init(void **ctx_ptr, int flags)
165 struct sigaction act;
167 pthread_key_create(&ctx_key, NULL);
168 pthread_mutex_init(&mtx_ctxsw, NULL);
171 sigemptyset(&act.sa_mask);
172 act.sa_handler = empth_alarm;
173 sigaction(SIGALRM, &act, NULL);
176 ctx = malloc(sizeof(empth_t));
178 logerror("pthread init failed: not enough memory");
182 ctx->desc = "empire main";
185 ctx->id = pthread_self();
187 pthread_setspecific(ctx_key, ctx);
188 pthread_mutex_lock(&mtx_ctxsw);
190 logerror("pthreads initialized");
196 * prio can be used for setting scheeduling policy but...
197 * it seems to be optional in POSIX threads and Solaris
198 * for example just ignores it.
199 * More then that priority is not needed even in lwp threads.
202 empth_create(int prio, void (*entry)(void *), int size, int flags,
203 char *name, char *desc, void *ud)
210 empth_status("creating new thread %s:%s", name, desc);
212 ctx = malloc(sizeof(empth_t));
214 logerror("not enough memory to create thread: %s (%s)",
218 ctx->name = strdup(name);
219 ctx->desc = strdup(desc);
224 eno = pthread_attr_init(&attr);
226 logerror("can not create thread attribute %s (%s): %s",
227 name, desc, strerror(eno));
230 if (size < PTHREAD_STACK_MIN)
231 size = PTHREAD_STACK_MIN;
232 pthread_attr_setstacksize(&attr, size);
233 pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
235 eno = pthread_create(&t, &attr, empth_start, ctx);
237 logerror("can not create thread: %s (%s): %s",
238 name, desc, strerror(eno));
241 empth_status("new thread id is %ld", (long)t);
246 pthread_attr_destroy(&attr);
253 empth_restorectx(void)
257 ctx_ptr = pthread_getspecific(ctx_key);
258 *udata = ctx_ptr->ud;
259 if (ctx_ptr->state == EMPTH_KILLED) {
260 empth_status("i am dead");
263 empth_status("context restored");
269 return pthread_getspecific(ctx_key);
277 pthread_mutex_unlock(&mtx_ctxsw);
278 empth_status("empth_exit");
279 ctx_ptr = pthread_getspecific(ctx_key);
280 /* We want to leave the main thread around forever, until it's time
281 for it to die for real (in a shutdown) */
282 if (!strcmp(ctx_ptr->name, "Main")) {
295 pthread_mutex_unlock(&mtx_ctxsw);
296 pthread_mutex_lock(&mtx_ctxsw);
301 empth_terminate(empth_t *a)
303 empth_status("killing thread %s", a->name);
304 a->state = EMPTH_KILLED;
305 pthread_kill(a->id, SIGALRM);
309 empth_select(int fd, int flags)
317 pthread_mutex_unlock(&mtx_ctxsw);
318 empth_status("%s select on %d",
319 flags == EMPTH_FD_READ ? "read" : "write", fd);
329 FD_SET(fd, &readmask);
332 FD_SET(fd, &writemask);
335 logerror("bad flag %d passed to empth_select", flags);
339 n = select(fd + 1, &readmask, &writemask, (fd_set *) 0, &tv);
342 if (errno == EINTR) {
343 /* go handle the signal */
344 empth_status("select broken by signal");
348 /* strange but we dont get EINTR on select broken by signal */
349 empth_status("select failed (%s)", strerror(errno));
354 if (flags == EMPTH_FD_READ && FD_ISSET(fd, &readmask)) {
355 empth_status("input ready");
358 if (flags == EMPTH_FD_WRITE && FD_ISSET(fd, &writemask)) {
359 empth_status("output ready");
365 pthread_mutex_lock(&mtx_ctxsw);
374 struct sigaction act;
375 empth_status("got alarm signal");
377 act.sa_flags &= ~SA_RESTART;
379 sigemptyset(&act.sa_mask);
380 act.sa_handler = empth_alarm;
381 sigaction(SIGALRM, &act, NULL);
385 empth_wakeup(empth_t *a)
387 empth_status("waking up thread %s", a->name);
388 pthread_kill(a->id, SIGALRM);
389 empth_status("waiting for it to run");
393 empth_sleep(time_t until)
397 empth_status("going to sleep %ld sec", until - time(0));
398 pthread_mutex_unlock(&mtx_ctxsw);
399 tv.tv_sec = until - time(NULL);
402 select(0, NULL, NULL, NULL, &tv);
403 } while ((tv.tv_sec = until - time(NULL)) > 0);
404 empth_status("sleep done. Waiting for lock");
405 pthread_mutex_lock(&mtx_ctxsw);
411 empth_sem_create(char *name, int cnt)
415 sm = malloc(sizeof(empth_sem_t));
417 logerror("out of memory at %s:%d", __FILE__, __LINE__);
420 strncpy(sm->name, name, sizeof(sm->name) - 1);
422 pthread_mutex_init(&sm->mtx_update, NULL);
423 pthread_mutex_init(&sm->mtx_sem, NULL);
424 pthread_cond_init(&sm->cnd_sem, NULL);
429 empth_sem_signal(empth_sem_t *sm)
431 empth_status("signal on semaphore %s:%d", sm->name, sm->count);
432 pthread_mutex_lock(&sm->mtx_update);
433 if (sm->count++ < 0) {
434 pthread_mutex_unlock(&sm->mtx_update);
435 pthread_mutex_lock(&sm->mtx_sem);
436 pthread_cond_signal(&sm->cnd_sem);
437 pthread_mutex_unlock(&sm->mtx_sem);
439 pthread_mutex_unlock(&sm->mtx_update);
443 empth_sem_wait(empth_sem_t *sm)
445 empth_status("wait on semaphore %s:%d", sm->name, sm->count);
446 pthread_mutex_lock(&sm->mtx_update);
447 if (--sm->count < 0) {
448 pthread_mutex_unlock(&sm->mtx_update);
449 empth_status("blocking");
450 pthread_mutex_unlock(&mtx_ctxsw);
451 pthread_mutex_lock(&sm->mtx_sem);
452 pthread_cond_wait(&sm->cnd_sem, &sm->mtx_sem);
453 empth_status("waking up");
454 pthread_mutex_unlock(&sm->mtx_sem);
455 pthread_mutex_lock(&mtx_ctxsw);
458 pthread_mutex_unlock(&sm->mtx_update);