src/etpan/etpan-thread-manager.c

   1 /*
   2  * Claws Mail -- a GTK based, lightweight, and fast e-mail client
   3  * Copyright (C) 2005-2012 DINH Viet Hoa and the Claws Mail team
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 3 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  17  *
  18  */
  19
  20 #ifdef HAVE_CONFIG_H
  21 #  include "config.h"
  22 #include "claws-features.h"
  23 #endif
  24
  25 #ifdef HAVE_LIBETPAN
  26
  27 #include "etpan-thread-manager.h"
  28
  29 #include <glib.h>
  30 #include <stdlib.h>
  31 #include <pthread.h>
  32 #include <libetpan/mailsem.h>
  33 #include <semaphore.h>
  34 #include <unistd.h>
  35 #include <fcntl.h>
  36
  37 #include "etpan-errors.h"
  38 #include "utils.h"
  39
  40 #define POOL_UNBOUND_MAX 4
  41
  42 #define POOL_INIT_SIZE 8
  43 #define OP_INIT_SIZE 8
  44
  45 static int etpan_thread_start(struct etpan_thread * thread);
  46 static void etpan_thread_free(struct etpan_thread * thread);
  47 static unsigned int etpan_thread_get_load(struct etpan_thread * thread);
  48 static int etpan_thread_is_bound(struct etpan_thread * thread);
  49 static int etpan_thread_manager_is_stopped(struct etpan_thread_manager * manager);
  50 static void etpan_thread_join(struct etpan_thread * thread);
  51 static struct etpan_thread * etpan_thread_new(void);
  52 static int etpan_thread_op_cancelled(struct etpan_thread_op * op);
  53 static void etpan_thread_op_lock(struct etpan_thread_op * op);
  54 static void etpan_thread_op_unlock(struct etpan_thread_op * op);
  55 static void etpan_thread_stop(struct etpan_thread * thread);
  56
  57 #if 0
  58 static void etpan_thread_bind(struct etpan_thread * thread);
  59 static int etpan_thread_manager_op_schedule(struct etpan_thread_manager * manager,
  60              struct etpan_thread_op * op);
  61 static void etpan_thread_manager_start(struct etpan_thread_manager * manager);
  62 static void etpan_thread_op_cancel(struct etpan_thread_op * op);
  63 #endif
  64
  65 enum {
  66   TERMINATE_STATE_NONE,
  67   TERMINATE_STATE_REQUESTED,
  68   TERMINATE_STATE_DONE,
  69 };
  70
  71 struct etpan_thread_manager * etpan_thread_manager_new(void)
  72 {
  73   struct etpan_thread_manager * manager;
  74   int r;
  75
  76   manager = malloc(sizeof(* manager));
  77   if (manager == NULL)
  78     goto err;
  79
  80   manager->thread_pool = carray_new(POOL_INIT_SIZE);
  81   if (manager->thread_pool == NULL)
  82     goto free;
  83
  84   manager->thread_pending = carray_new(POOL_INIT_SIZE);
  85   if (manager->thread_pending == NULL)
  86     goto free_pool;
  87
  88   manager->can_create_thread = 1;
  89   manager->unbound_count = 0;
  90
  91   r = pipe(manager->notify_fds);
  92   if (r < 0)
  93     goto free_pending;
  94
  95   return manager;
  96
  97  free_pending:
  98   carray_free(manager->thread_pending);
  99  free_pool:
 100   carray_free(manager->thread_pool);
 101  free:
 102   free(manager);
 103  err:
 104   return NULL;
 105 }
 106
 107 void etpan_thread_manager_free(struct etpan_thread_manager * manager)
 108 {
 109   close(manager->notify_fds[1]);
 110   close(manager->notify_fds[0]);
 111   carray_free(manager->thread_pending);
 112   carray_free(manager->thread_pool);
 113   free(manager);
 114 }
 115
 116 static struct etpan_thread * etpan_thread_new(void)
 117 {
 118   struct etpan_thread * thread;
 119   int r;
 120
 121   thread = malloc(sizeof(* thread));
 122   if (thread == NULL)
 123     goto err;
 124
 125   r = pthread_mutex_init(&thread->lock, NULL);
 126   if (r != 0)
 127     goto free;
 128
 129   thread->op_list = carray_new(OP_INIT_SIZE);
 130   if (thread->op_list == NULL)
 131     goto destroy_lock;
 132
 133   thread->op_done_list = carray_new(OP_INIT_SIZE);
 134   if (thread->op_done_list == NULL)
 135     goto free_op_list;
 136
 137   thread->start_sem = mailsem_new();
 138   if (thread->start_sem == NULL)
 139     goto free_op_done_list;
 140
 141   thread->stop_sem = mailsem_new();
 142   if (thread->stop_sem == NULL)
 143     goto free_startsem;
 144
 145   thread->op_sem = mailsem_new();
 146   if (thread->op_sem == NULL)
 147     goto free_stopsem;
 148
 149   thread->manager = NULL;
 150   thread->bound_count = 0;
 151   thread->terminate_state = TERMINATE_STATE_NONE;
 152
 153   return thread;
 154
 155  free_stopsem:
 156   mailsem_free(thread->stop_sem);
 157  free_startsem:
 158   mailsem_free(thread->start_sem);
 159  free_op_done_list:
 160   carray_free(thread->op_done_list);
 161  free_op_list:
 162   carray_free(thread->op_list);
 163  destroy_lock:
 164   pthread_mutex_destroy(&thread->lock);
 165  free:
 166   free(thread);
 167  err:
 168   return NULL;
 169 }
 170
 171 static void etpan_thread_free(struct etpan_thread * thread)
 172 {
 173   mailsem_free(thread->op_sem);
 174   mailsem_free(thread->stop_sem);
 175   mailsem_free(thread->start_sem);
 176   carray_free(thread->op_done_list);
 177   carray_free(thread->op_list);
 178   pthread_mutex_destroy(&thread->lock);
 179   free(thread);
 180 }
 181
 182 struct etpan_thread_op * etpan_thread_op_new(void)
 183 {
 184   struct etpan_thread_op * op;
 185   int r;
 186
 187   op = malloc(sizeof(* op));
 188   if (op == NULL)
 189     goto err;
 190
 191   memset(op, 0, sizeof(* op));
 192
 193   r = pthread_mutex_init(&op->lock, NULL);
 194   if (r != 0)
 195     goto free;
 196
 197   return op;
 198
 199  free:
 200   free(op);
 201  err:
 202   return NULL;
 203 }
 204
 205 void etpan_thread_op_free(struct etpan_thread_op * op)
 206 {
 207   pthread_mutex_destroy(&op->lock);
 208   free(op);
 209 }
 210
 211 static struct etpan_thread *
 212 etpan_thread_manager_create_thread(struct etpan_thread_manager * manager)
 213 {
 214   struct etpan_thread * thread;
 215   int r;
 216
 217   thread = etpan_thread_new();
 218   if (thread == NULL)
 219     goto err;
 220
 221   thread->manager = manager;
 222
 223   r = etpan_thread_start(thread);
 224   if (r != NO_ERROR)
 225     goto free_thread;
 226
 227   r = carray_add(manager->thread_pool, thread, NULL);
 228   if (r < 0) {
 229     etpan_thread_stop(thread);
 230     goto free_thread;
 231   }
 232
 233   return thread;
 234
 235  free_thread:
 236   etpan_thread_free(thread);
 237  err:
 238   return NULL;
 239 }
 240
 241 static void
 242 etpan_thread_manager_terminate_thread(struct etpan_thread_manager * manager,
 243     struct etpan_thread * thread)
 244 {
 245   unsigned int i;
 246   int r;
 247
 248   for(i = 0 ; i < carray_count(manager->thread_pool) ; i ++) {
 249     if (carray_get(manager->thread_pool, i) == thread) {
 250       carray_delete(manager->thread_pool, i);
 251       break;
 252     }
 253   }
 254
 255   if (!etpan_thread_is_bound(thread))
 256     manager->unbound_count --;
 257
 258   r = carray_add(manager->thread_pending, thread, NULL);
 259   if (r < 0) {
 260     g_warning("complete failure of thread due to lack of memory (thread stop)");
 261   }
 262
 263   etpan_thread_stop(thread);
 264 }
 265
 266 static void manager_notify(struct etpan_thread_manager * manager)
 267 {
 268   char ch;
 269   ssize_t r;
 270
 271   ch = 1;
 272   r = write(manager->notify_fds[1], &ch, 1);
 273   if (r < 0) {
 274     g_warning("error writing notification to etpan thread manager");
 275   }
 276 }
 277
 278 static void manager_ack(struct etpan_thread_manager * manager)
 279 {
 280 #ifndef G_OS_WIN32
 281   char ch;
 282   ssize_t r;
 283   r = read(manager->notify_fds[0], &ch, 1);
 284   if (r != 1) {
 285     g_warning("error reading notification from etpan thread manager");
 286   }
 287 #else
 288   /* done in the GIOChannel handler in imap-thread.c and nntp-thread.c */
 289 #endif
 290 }
 291
 292 static void thread_lock(struct etpan_thread * thread)
 293 {
 294   pthread_mutex_lock(&thread->lock);
 295 }
 296
 297 static void thread_unlock(struct etpan_thread * thread)
 298 {
 299   pthread_mutex_unlock(&thread->lock);
 300 }
 301
 302 static void thread_notify(struct etpan_thread * thread)
 303 {
 304   manager_notify(thread->manager);
 305 }
 306
 307 static void * thread_run(void * data)
 308 {
 309   struct etpan_thread * thread;
 310   int r;
 311
 312   thread = data;
 313
 314   mailsem_up(thread->start_sem);
 315
 316   while (1) {
 317     int do_quit;
 318     struct etpan_thread_op * op;
 319
 320     mailsem_down(thread->op_sem);
 321
 322     do_quit = 0;
 323     op = NULL;
 324     thread_lock(thread);
 325     if (carray_count(thread->op_list) > 0) {
 326       op = carray_get(thread->op_list, 0);
 327       carray_delete_slow(thread->op_list, 0);
 328     }
 329     else {
 330       do_quit = 1;
 331     }
 332     thread_unlock(thread);
 333
 334     if (do_quit) {
 335       break;
 336     }
 337
 338     if (!etpan_thread_op_cancelled(op)) {
 339       if (op->run != NULL)
 340         op->run(op);
 341     }
 342
 343     thread_lock(thread);
 344     r = carray_add(thread->op_done_list, op, NULL);
 345     if (r < 0) {
 346       g_warning("complete failure of thread due to lack of memory (op done)");
 347     }
 348     thread_unlock(thread);
 349
 350     thread_notify(thread);
 351   }
 352
 353   thread_lock(thread);
 354   thread->terminate_state = TERMINATE_STATE_DONE;
 355   thread_unlock(thread);
 356
 357   thread_notify(thread);
 358
 359   mailsem_up(thread->stop_sem);
 360
 361   return NULL;
 362 }
 363
 364 static int etpan_thread_start(struct etpan_thread * thread)
 365 {
 366   int r;
 367
 368   r = pthread_create(&thread->th_id, NULL, thread_run, thread);
 369   if (r != 0)
 370     return ERROR_MEMORY;
 371
 372   mailsem_down(thread->start_sem);
 373
 374   return NO_ERROR;
 375 }
 376
 377 static void etpan_thread_stop(struct etpan_thread * thread)
 378 {
 379   thread_lock(thread);
 380   thread->terminate_state = TERMINATE_STATE_REQUESTED;
 381   thread_unlock(thread);
 382
 383   mailsem_up(thread->op_sem);
 384
 385   /* this thread will be joined in the manager loop */
 386 }
 387
 388 static int etpan_thread_is_stopped(struct etpan_thread * thread)
 389 {
 390   int stopped;
 391
 392   thread_lock(thread);
 393   stopped = (thread->terminate_state == TERMINATE_STATE_DONE);
 394   thread_unlock(thread);
 395
 396   return stopped;
 397 }
 398
 399 static void etpan_thread_join(struct etpan_thread * thread)
 400 {
 401   mailsem_down(thread->stop_sem);
 402   pthread_join(thread->th_id, NULL);
 403 }
 404
 405 struct etpan_thread *
 406 etpan_thread_manager_get_thread(struct etpan_thread_manager * manager)
 407 {
 408   struct etpan_thread * chosen_thread;
 409   unsigned int chosen_thread_load;
 410   unsigned int i;
 411   struct etpan_thread * thread;
 412
 413   /* chose a thread */
 414
 415   chosen_thread = NULL;
 416   chosen_thread_load = 0;
 417
 418   for(i = 0 ; i < carray_count(manager->thread_pool) ; i ++) {
 419     thread = carray_get(manager->thread_pool, i);
 420     if (etpan_thread_is_bound(thread))
 421       continue;
 422
 423     if (chosen_thread == NULL) {
 424       chosen_thread = thread;
 425       chosen_thread_load = etpan_thread_get_load(thread);
 426
 427       if (chosen_thread_load == 0)
 428         break;
 429     }
 430     else {
 431       unsigned int load;
 432
 433       load = etpan_thread_get_load(thread);
 434
 435       if (load < chosen_thread_load) {
 436         chosen_thread = thread;
 437         chosen_thread_load = load;
 438       }
 439     }
 440   }
 441
 442   if (chosen_thread != NULL) {
 443     if (manager->can_create_thread && (chosen_thread_load != 0)) {
 444       chosen_thread = NULL;
 445     }
 446   }
 447
 448   /* choice done */
 449
 450   if (chosen_thread != NULL)
 451     return chosen_thread;
 452
 453   thread = etpan_thread_manager_create_thread(manager);
 454   if (thread == NULL)
 455     goto err;
 456
 457   manager->unbound_count ++;
 458   if (manager->unbound_count >= POOL_UNBOUND_MAX)
 459     manager->can_create_thread = 0;
 460
 461   return thread;
 462
 463  err:
 464   return NULL;
 465 }
 466
 467 static unsigned int etpan_thread_get_load(struct etpan_thread * thread)
 468 {
 469   unsigned int load;
 470
 471   thread_lock(thread);
 472   load = carray_count(thread->op_list);
 473   thread_unlock(thread);
 474
 475   return load;
 476 }
 477
 478 #if 0
 479 static void etpan_thread_bind(struct etpan_thread * thread)
 480 {
 481   thread->bound_count ++;
 482 }
 483 #endif
 484
 485 void etpan_thread_unbind(struct etpan_thread * thread)
 486 {
 487   thread->bound_count --;
 488 }
 489
 490 static int etpan_thread_is_bound(struct etpan_thread * thread)
 491 {
 492   return (thread->bound_count != 0);
 493 }
 494
 495 int etpan_thread_op_schedule(struct etpan_thread * thread,
 496                              struct etpan_thread_op * op)
 497 {
 498   int r;
 499
 500   if (thread->terminate_state != TERMINATE_STATE_NONE)
 501     return ERROR_INVAL;
 502
 503   thread_lock(thread);
 504   r = carray_add(thread->op_list, op, NULL);
 505   thread_unlock(thread);
 506
 507   if (r < 0)
 508     return ERROR_MEMORY;
 509
 510   op->thread = thread;
 511   mailsem_up(thread->op_sem);
 512
 513   return NO_ERROR;
 514 }
 515
 516 static void etpan_thread_op_lock(struct etpan_thread_op * op)
 517 {
 518   pthread_mutex_lock(&op->lock);
 519 }
 520
 521 static void etpan_thread_op_unlock(struct etpan_thread_op * op)
 522 {
 523   pthread_mutex_unlock(&op->lock);
 524 }
 525
 526 static int etpan_thread_op_cancelled(struct etpan_thread_op * op)
 527 {
 528   int cancelled;
 529
 530   cancelled = 0;
 531   etpan_thread_op_lock(op);
 532   if (op->cancellable)
 533     cancelled = op->cancelled;
 534   etpan_thread_op_unlock(op);
 535
 536   return cancelled;
 537 }
 538
 539 int etpan_thread_manager_get_fd(struct etpan_thread_manager * manager)
 540 {
 541   return manager->notify_fds[0];
 542 }
 543
 544 static void loop_thread_list(carray * op_to_notify,
 545     carray * thread_list)
 546 {
 547   unsigned int i;
 548   int r;
 549
 550   for(i = 0 ; i < carray_count(thread_list) ; i ++) {
 551     struct etpan_thread * thread;
 552     unsigned int j;
 553
 554     thread = carray_get(thread_list, i);
 555
 556     thread_lock(thread);
 557
 558     for(j = 0 ; j < carray_count(thread->op_done_list) ; j ++) {
 559       struct etpan_thread_op * op;
 560
 561       op = carray_get(thread->op_done_list, j);
 562       r = carray_add(op_to_notify, op, NULL);
 563       if (r < 0) {
 564         g_warning("complete failure of thread due to lack of memory (callback)");
 565         break;
 566       }
 567     }
 568     carray_set_size(thread->op_done_list, 0);
 569
 570     thread_unlock(thread);
 571   }
 572 }
 573
 574 void etpan_thread_manager_loop(struct etpan_thread_manager * manager)
 575 {
 576   carray * op_to_notify;
 577   unsigned int i;
 578
 579   manager_ack(manager);
 580
 581   op_to_notify = carray_new(OP_INIT_SIZE);
 582
 583   loop_thread_list(op_to_notify, manager->thread_pool);
 584   loop_thread_list(op_to_notify, manager->thread_pending);
 585
 586   for(i = 0 ; i < carray_count(op_to_notify) ; i ++) {
 587     struct etpan_thread_op * op;
 588
 589     op = carray_get(op_to_notify, i);
 590
 591     etpan_thread_op_lock(op);
 592
 593     if (!op->callback_called) {
 594       if (op->callback != NULL)
 595         op->callback(op->cancelled, op->result, op->callback_data);
 596     }
 597
 598     etpan_thread_op_unlock(op);
 599
 600     if (op->cleanup != NULL)
 601       op->cleanup(op);
 602   }
 603
 604   carray_free(op_to_notify);
 605
 606   i = 0;
 607   while (i < carray_count(manager->thread_pending)) {
 608     struct etpan_thread * thread;
 609
 610     thread = carray_get(manager->thread_pending, i);
 611
 612     if (etpan_thread_is_stopped(thread)) {
 613       etpan_thread_join(thread);
 614
 615       etpan_thread_free(thread);
 616
 617       carray_delete_slow(manager->thread_pending, i);
 618     }
 619     else {
 620       i ++;
 621     }
 622   }
 623 }
 624
 625 #if 0
 626 static void etpan_thread_manager_start(struct etpan_thread_manager * manager)
 627 {
 628   /* do nothing */
 629 }
 630 #endif
 631
 632 void etpan_thread_manager_stop(struct etpan_thread_manager * manager)
 633 {
 634   while (carray_count(manager->thread_pool) > 0) {
 635     struct etpan_thread * thread;
 636
 637     thread = carray_get(manager->thread_pool, 0);
 638     etpan_thread_manager_terminate_thread(manager, thread);
 639   }
 640 }
 641
 642 static int etpan_thread_manager_is_stopped(struct etpan_thread_manager * manager)
 643 {
 644   return ((carray_count(manager->thread_pending) == 0) &&
 645       (carray_count(manager->thread_pool) == 0));
 646 }
 647
 648 void etpan_thread_manager_join(struct etpan_thread_manager * manager)
 649 {
 650   while (!etpan_thread_manager_is_stopped(manager)) {
 651     etpan_thread_manager_loop(manager);
 652   }
 653 }
 654 #endif