1 /* 2 * Copyright (c) 2008 Bret S. Lambert <blambert@openbsd.org> 3 * 4 * Permission to use, copy, modify, and distribute this software for any 5 * purpose with or without fee is hereby granted, provided that the above 6 * copyright notice and this permission notice appear in all copies. 7 * 8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 15 */ 16 17 #include <stdio.h> 18 #include <string.h> 19 #include <unistd.h> 20 #include <pthread.h> 21 22 #define THREAD_COUNT 64 23 24 #define TEXT "barnacles" 25 #define TEXT_N "barnacles\n" 26 27 void run_threads(void (*)(void *), void *); 28 29 static pthread_rwlock_t start; 30 static void (*real_func)(void *); 31 32 static void * 33 thread(void *arg) 34 { 35 int r; 36 37 if ((r = pthread_rwlock_rdlock(&start))) 38 errx(1, "could not obtain lock in thread: %s", strerror(r)); 39 real_func(arg); 40 if ((r = pthread_rwlock_unlock(&start))) 41 errx(1, "could not release lock in thread: %s", strerror(r)); 42 return NULL; 43 } 44 45 void 46 run_threads(void (*func)(void *), void *arg) 47 { 48 pthread_t self, pthread[THREAD_COUNT]; 49 int i, r; 50 51 self = pthread_self(); 52 real_func = func; 53 if ((r = pthread_rwlock_init(&start, NULL))) 54 errx(1, "could not initialize lock: %s", strerror(r)); 55 56 if ((r = pthread_rwlock_wrlock(&start))) /* block */ 57 errx(1, "could not lock lock: %s", strerror(r)); 58 59 for (i = 0; i < THREAD_COUNT; i++) 60 if ((r = pthread_create(&pthread[i], NULL, thread, arg))) { 61 warnx("could not create thread: %s", strerror(r)); 62 pthread[i] = self; 63 } 64 65 66 if ((r = pthread_rwlock_unlock(&start))) /* unleash */ 67 errx(1, "could not release lock: %s", strerror(r)); 68 69 sleep(1); 70 71 if ((r = pthread_rwlock_wrlock(&start))) /* sync */ 72 errx(1, "parent could not sync with children: %s", 73 strerror(r)); 74 75 for (i = 0; i < THREAD_COUNT; i++) 76 if (! pthread_equal(pthread[i], self) && 77 (r = pthread_join(pthread[i], NULL))) 78 warnx("could not join thread: %s", strerror(r)); 79 } 80 81