1 /*** 2 This file is part of avahi. 3 4 avahi is free software; you can redistribute it and/or modify it 5 under the terms of the GNU Lesser General Public License as 6 published by the Free Software Foundation; either version 2.1 of the 7 License, or (at your option) any later version. 8 9 avahi is distributed in the hope that it will be useful, but WITHOUT 10 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 11 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General 12 Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with avahi; if not, write to the Free Software 16 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 17 USA. 18 ***/ 19 20 #ifdef HAVE_CONFIG_H 21 #include <config.h> 22 #endif 23 24 #include <sys/poll.h> 25 #include <assert.h> 26 #include <string.h> 27 #include <errno.h> 28 #include <unistd.h> 29 #include <fcntl.h> 30 #include <stdio.h> 31 #include <pthread.h> 32 #include <signal.h> 33 34 #include "llist.h" 35 #include "avahi-malloc.h" 36 #include "timeval.h" 37 #include "simple-watch.h" 38 #include "thread-watch.h" 39 40 struct AvahiThreadedPoll { 41 AvahiSimplePoll *simple_poll; 42 pthread_t thread_id; 43 pthread_mutex_t mutex; 44 int thread_running; 45 int retval; 46 }; 47 48 static int poll_func(struct pollfd *ufds, unsigned int nfds, int timeout, void *userdata) { 49 pthread_mutex_t *mutex = userdata; 50 int r; 51 52 /* Before entering poll() we unlock the mutex, so that 53 * avahi_simple_poll_quit() can succeed from another thread. */ 54 55 pthread_mutex_unlock(mutex); 56 r = poll(ufds, nfds, timeout); 57 pthread_mutex_lock(mutex); 58 59 return r; 60 } 61 62 static void* thread(void *userdata){ 63 AvahiThreadedPoll *p = userdata; 64 sigset_t mask; 65 66 /* Make sure that signals are delivered to the main thread */ 67 sigfillset(&mask); 68 pthread_sigmask(SIG_BLOCK, &mask, NULL); 69 70 pthread_mutex_lock(&p->mutex); 71 p->retval = avahi_simple_poll_loop(p->simple_poll); 72 pthread_mutex_unlock(&p->mutex); 73 74 return NULL; 75 } 76 77 AvahiThreadedPoll *avahi_threaded_poll_new(void) { 78 AvahiThreadedPoll *p; 79 80 if (!(p = avahi_new(AvahiThreadedPoll, 1))) 81 goto fail; /* OOM */ 82 83 if (!(p->simple_poll = avahi_simple_poll_new())) 84 goto fail; 85 86 pthread_mutex_init(&p->mutex, NULL); 87 88 avahi_simple_poll_set_func(p->simple_poll, poll_func, &p->mutex); 89 90 p->thread_running = 0; 91 92 return p; 93 94 fail: 95 if (p) { 96 if (p->simple_poll) { 97 avahi_simple_poll_free(p->simple_poll); 98 pthread_mutex_destroy(&p->mutex); 99 } 100 101 avahi_free(p); 102 } 103 104 return NULL; 105 } 106 107 void avahi_threaded_poll_free(AvahiThreadedPoll *p) { 108 assert(p); 109 110 /* Make sure that this function is not called from the helper thread */ 111 assert(!p->thread_running || !pthread_equal(pthread_self(), p->thread_id)); 112 113 if (p->thread_running) 114 avahi_threaded_poll_stop(p); 115 116 if (p->simple_poll) 117 avahi_simple_poll_free(p->simple_poll); 118 119 pthread_mutex_destroy(&p->mutex); 120 avahi_free(p); 121 } 122 123 const AvahiPoll* avahi_threaded_poll_get(AvahiThreadedPoll *p) { 124 assert(p); 125 126 return avahi_simple_poll_get(p->simple_poll); 127 } 128 129 int avahi_threaded_poll_start(AvahiThreadedPoll *p) { 130 assert(p); 131 132 assert(!p->thread_running); 133 134 if (pthread_create(&p->thread_id, NULL, thread, p) < 0) 135 return -1; 136 137 p->thread_running = 1; 138 139 return 0; 140 } 141 142 int avahi_threaded_poll_stop(AvahiThreadedPoll *p) { 143 assert(p); 144 145 if (!p->thread_running) 146 return -1; 147 148 /* Make sure that this function is not called from the helper thread */ 149 assert(!pthread_equal(pthread_self(), p->thread_id)); 150 151 pthread_mutex_lock(&p->mutex); 152 avahi_simple_poll_quit(p->simple_poll); 153 pthread_mutex_unlock(&p->mutex); 154 155 pthread_join(p->thread_id, NULL); 156 p->thread_running = 0; 157 158 return p->retval; 159 } 160 161 void avahi_threaded_poll_quit(AvahiThreadedPoll *p) { 162 assert(p); 163 164 /* Make sure that this function is called from the helper thread */ 165 assert(pthread_equal(pthread_self(), p->thread_id)); 166 167 avahi_simple_poll_quit(p->simple_poll); 168 } 169 170 void avahi_threaded_poll_lock(AvahiThreadedPoll *p) { 171 assert(p); 172 173 /* Make sure that this function is not called from the helper thread */ 174 assert(!p->thread_running || !pthread_equal(pthread_self(), p->thread_id)); 175 176 pthread_mutex_lock(&p->mutex); 177 } 178 179 void avahi_threaded_poll_unlock(AvahiThreadedPoll *p) { 180 assert(p); 181 182 /* Make sure that this function is not called from the helper thread */ 183 assert(!p->thread_running || !pthread_equal(pthread_self(), p->thread_id)); 184 185 pthread_mutex_unlock(&p->mutex); 186 } 187