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 <err.h> 18 #include <stdio.h> 19 #include <stdlib.h> 20 #include <string.h> 21 #include <unistd.h> 22 #include <pthread.h> 23 24 #define THREAD_COUNT 64 25 26 #define TEXT "barnacles" 27 #define TEXT_N "barnacles\n" 28 29 void run_threads(void (*)(void *), void *); 30 31 static pthread_rwlock_t start; 32 static void (*real_func)(void *); 33 34 static void * 35 thread(void *arg) 36 { 37 int r; 38 39 if ((r = pthread_rwlock_rdlock(&start))) 40 errc(1, r, "could not obtain lock in thread"); 41 real_func(arg); 42 if ((r = pthread_rwlock_unlock(&start))) 43 errc(1, r, "could not release lock in thread"); 44 return NULL; 45 } 46 47 void 48 run_threads(void (*func)(void *), void *arg) 49 { 50 pthread_t self, pthread[THREAD_COUNT]; 51 int i, r; 52 53 self = pthread_self(); 54 real_func = func; 55 if ((r = pthread_rwlock_init(&start, NULL))) 56 errc(1, r, "could not initialize lock"); 57 58 if ((r = pthread_rwlock_wrlock(&start))) /* block */ 59 errc(1, r, "could not lock lock"); 60 61 for (i = 0; i < THREAD_COUNT; i++) 62 if ((r = pthread_create(&pthread[i], NULL, thread, arg))) { 63 warnc(r, "could not create thread"); 64 pthread[i] = self; 65 } 66 67 68 if ((r = pthread_rwlock_unlock(&start))) /* unleash */ 69 errc(1, r, "could not release lock"); 70 71 sleep(1); 72 73 if ((r = pthread_rwlock_wrlock(&start))) /* sync */ 74 errx(1, "parent could not sync with children: %s", 75 strerror(r)); 76 77 for (i = 0; i < THREAD_COUNT; i++) 78 if (! pthread_equal(pthread[i], self) && 79 (r = pthread_join(pthread[i], NULL))) 80 warnc(r, "could not join thread"); 81 } 82 83