src/charon/bus/bus.c

   1 /*
   2  * Copyright (C) 2006 Martin Willi
   3  * Hochschule fuer Technik Rapperswil
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2 of the License, or (at your
   8  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * for more details.
  14  *
  15  * $Id$
  16  */
  17
  18 #include "bus.h"
  19
  20 #include <pthread.h>
  21
  22 #include <daemon.h>
  23 #include <utils/mutex.h>
  24
  25 ENUM(signal_names, SIG_ANY, SIG_MAX,
  26         /** should not get printed */
  27         "SIG_ANY",
  28         /** debugging message types */
  29         "DMN",
  30         "MGR",
  31         "IKE",
  32         "CHD",
  33         "JOB",
  34         "CFG",
  35         "KNL",
  36         "NET",
  37         "ENC",
  38         "LIB",
  39         /** should not get printed */
  40         "SIG_DBG_MAX",
  41         /** all level0 signals are AUDIT signals */
  42         "AUD", "AUD", "AUD",
  43         "AUD", "AUD", "AUD",
  44         "AUD", "AUD", "AUD",
  45         "AUD", "AUD", "AUD",
  46         "AUD", "AUD", "AUD",
  47         "AUD", "AUD", "AUD",
  48         "AUD", "AUD", "AUD",
  49         "AUD", "AUD", "AUD",
  50         /** should not get printed */
  51         "SIG_MAX",
  52 );
  53
  54 typedef struct private_bus_t private_bus_t;
  55
  56 /**
  57  * Private data of a bus_t object.
  58  */
  59 struct private_bus_t {
  60         /**
  61          * Public part of a bus_t object.
  62          */
  63         bus_t public;
  64
  65         /**
  66          * List of registered listeners as entry_t's
  67          */
  68         linked_list_t *listeners;
  69
  70         /**
  71          * mutex to synchronize active listeners, recursively
  72          */
  73         mutex_t *mutex;
  74
  75         /**
  76          * Thread local storage for a unique, simple thread ID
  77          */
  78         pthread_key_t thread_id;
  79
  80         /**
  81          * Thread local storage the threads IKE_SA
  82          */
  83         pthread_key_t thread_sa;
  84 };
  85
  86 typedef struct entry_t entry_t;
  87
  88 /**
  89  * a listener entry, either active or passive
  90  */
  91 struct entry_t {
  92
  93         /**
  94          * registered listener interface
  95          */
  96         bus_listener_t *listener;
  97
  98         /**
  99          * is this a active listen() call with a blocking thread
 100          */
 101         bool blocker;
 102
 103         /**
 104          * condvar where active listeners wait
 105          */
 106         condvar_t *condvar;
 107 };
 108
 109 /**
 110  * create a listener entry
 111  */
 112 static entry_t *entry_create(bus_listener_t *listener, bool blocker)
 113 {
 114         entry_t *this = malloc_thing(entry_t);
 115
 116         this->listener = listener;
 117         this->blocker = blocker;
 118         this->condvar = condvar_create(CONDVAR_DEFAULT);
 119
 120         return this;
 121 }
 122
 123 /**
 124  * destroy an entry_t
 125  */
 126 static void entry_destroy(entry_t *entry)
 127 {
 128         entry->condvar->destroy(entry->condvar);
 129         free(entry);
 130 }
 131
 132 /**
 133  * Get a unique thread number for a calling thread. Since
 134  * pthread_self returns large and ugly numbers, use this function
 135  * for logging; these numbers are incremental starting at 1
 136  */
 137 static int get_thread_number(private_bus_t *this)
 138 {
 139         static long current_num = 0;
 140         long stored_num;
 141
 142         stored_num = (long)pthread_getspecific(this->thread_id);
 143         if (stored_num == 0)
 144         {       /* first call of current thread */
 145                 pthread_setspecific(this->thread_id, (void*)++current_num);
 146                 return current_num;
 147         }
 148         else
 149         {
 150                 return stored_num;
 151         }
 152 }
 153
 154 /**
 155  * Implementation of bus_t.add_listener.
 156  */
 157 static void add_listener(private_bus_t *this, bus_listener_t *listener)
 158 {
 159         this->mutex->lock(this->mutex);
 160         this->listeners->insert_last(this->listeners, entry_create(listener, FALSE));
 161         this->mutex->unlock(this->mutex);
 162 }
 163
 164 /**
 165  * Implementation of bus_t.remove_listener.
 166  */
 167 static void remove_listener(private_bus_t *this, bus_listener_t *listener)
 168 {
 169         iterator_t *iterator;
 170         entry_t *entry;
 171
 172         this->mutex->lock(this->mutex);
 173         iterator = this->listeners->create_iterator(this->listeners, TRUE);
 174         while (iterator->iterate(iterator, (void**)&entry))
 175         {
 176                 if (entry->listener == listener)
 177                 {
 178                         iterator->remove(iterator);
 179                         entry_destroy(entry);
 180                         break;
 181                 }
 182         }
 183         iterator->destroy(iterator);
 184         this->mutex->unlock(this->mutex);
 185 }
 186
 187 typedef struct cleanup_data_t cleanup_data_t;
 188
 189 /**
 190  * data to remove a listener using pthread_cleanup handler
 191  */
 192 struct cleanup_data_t {
 193         /** bus instance */
 194         private_bus_t *this;
 195         /** listener entry */
 196         entry_t *entry;
 197 };
 198
 199 /**
 200  * pthread_cleanup handler to remove a listener
 201  */
 202 static void listener_cleanup(cleanup_data_t *data)
 203 {
 204         iterator_t *iterator;
 205         entry_t *entry;
 206
 207         iterator = data->this->listeners->create_iterator(data->this->listeners, TRUE);
 208         while (iterator->iterate(iterator, (void**)&entry))
 209         {
 210                 if (entry == data->entry)
 211                 {
 212                         iterator->remove(iterator);
 213                         entry_destroy(entry);
 214                         break;
 215                 }
 216         }
 217         iterator->destroy(iterator);
 218 }
 219
 220 /**
 221  * Implementation of bus_t.listen.
 222  */
 223 static void listen_(private_bus_t *this, bus_listener_t *listener, job_t *job)
 224 {
 225         int old;
 226         cleanup_data_t data;
 227
 228         data.this = this;
 229         data.entry = entry_create(listener, TRUE);
 230
 231         this->mutex->lock(this->mutex);
 232         this->listeners->insert_last(this->listeners, data.entry);
 233         charon->processor->queue_job(charon->processor, job);
 234         pthread_cleanup_push((void*)this->mutex->unlock, this->mutex);
 235         pthread_cleanup_push((void*)listener_cleanup, &data);
 236         pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, &old);
 237         while (data.entry->blocker)
 238         {
 239                 data.entry->condvar->wait(data.entry->condvar, this->mutex);
 240         }
 241         pthread_setcancelstate(old, NULL);
 242         pthread_cleanup_pop(FALSE);
 243         /* unlock mutex */
 244         pthread_cleanup_pop(TRUE);
 245         entry_destroy(data.entry);
 246 }
 247
 248 /**
 249  * Implementation of bus_t.set_sa.
 250  */
 251 static void set_sa(private_bus_t *this, ike_sa_t *ike_sa)
 252 {
 253         pthread_setspecific(this->thread_sa, ike_sa);
 254 }
 255
 256
 257 /**
 258  * Implementation of bus_t.vsignal.
 259  */
 260 static void vsignal(private_bus_t *this, signal_t signal, level_t level,
 261                                         char* format, va_list args)
 262 {
 263         iterator_t *iterator;
 264         entry_t *entry;
 265         ike_sa_t *ike_sa;
 266         long thread;
 267
 268         this->mutex->lock(this->mutex);
 269         ike_sa = pthread_getspecific(this->thread_sa);
 270         thread = get_thread_number(this);
 271
 272         iterator = this->listeners->create_iterator(this->listeners, TRUE);
 273         while (iterator->iterate(iterator, (void**)&entry))
 274         {
 275                 va_list args_copy;
 276                 va_copy(args_copy, args);
 277                 if (!entry->listener->signal(entry->listener, signal, level, thread,
 278                                                                          ike_sa, format, args_copy))
 279                 {
 280                         iterator->remove(iterator);
 281                         if (entry->blocker)
 282                         {
 283                                 entry->blocker = FALSE;
 284                                 entry->condvar->signal(entry->condvar);
 285                         }
 286                         else
 287                         {
 288                                 entry_destroy(entry);
 289                         }
 290                 }
 291                 va_end(args_copy);
 292         }
 293         iterator->destroy(iterator);
 294
 295         this->mutex->unlock(this->mutex);
 296 }
 297
 298 /**
 299  * Implementation of bus_t.signal.
 300  */
 301 static void signal_(private_bus_t *this, signal_t signal, level_t level,
 302                                         char* format, ...)
 303 {
 304         va_list args;
 305
 306         va_start(args, format);
 307         vsignal(this, signal, level, format, args);
 308         va_end(args);
 309 }
 310
 311 /**
 312  * Implementation of bus_t.destroy.
 313  */
 314 static void destroy(private_bus_t *this)
 315 {
 316         this->mutex->destroy(this->mutex);
 317         this->listeners->destroy_function(this->listeners, (void*)entry_destroy);
 318         free(this);
 319 }
 320
 321 /*
 322  * Described in header.
 323  */
 324 bus_t *bus_create()
 325 {
 326         private_bus_t *this = malloc_thing(private_bus_t);
 327
 328         this->public.add_listener = (void(*)(bus_t*,bus_listener_t*))add_listener;
 329         this->public.remove_listener = (void(*)(bus_t*,bus_listener_t*))remove_listener;
 330         this->public.listen = (void(*)(bus_t*, bus_listener_t *listener, job_t *job))listen_;
 331         this->public.set_sa = (void(*)(bus_t*,ike_sa_t*))set_sa;
 332         this->public.signal = (void(*)(bus_t*,signal_t,level_t,char*,...))signal_;
 333         this->public.vsignal = (void(*)(bus_t*,signal_t,level_t,char*,va_list))vsignal;
 334         this->public.destroy = (void(*)(bus_t*)) destroy;
 335
 336         this->listeners = linked_list_create();
 337         this->mutex = mutex_create(MUTEX_DEFAULT);
 338         pthread_key_create(&this->thread_id, NULL);
 339         pthread_key_create(&this->thread_sa, NULL);
 340
 341         return &this->public;
 342 }
 343