src/mpdclient.c

   1 /* ncmpc (Ncurses MPD Client)
   2  * (c) 2004-2009 The Music Player Daemon Project
   3  * Project homepage: http://musicpd.org
   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 2 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 along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "mpdclient.h"
  21 #include "filelist.h"
  22 #include "screen_client.h"
  23 #include "config.h"
  24 #include "options.h"
  25 #include "strfsong.h"
  26 #include "utils.h"
  27
  28 #include <mpd/client.h>
  29
  30 #include <stdlib.h>
  31 #include <unistd.h>
  32 #include <time.h>
  33 #include <string.h>
  34
  35 #define ENABLE_FANCY_PLAYLIST_MANAGMENT_CMD_DELETE
  36 #define ENABLE_FANCY_PLAYLIST_MANAGMENT_CMD_MOVE
  37
  38 #define BUFSIZE 1024
  39
  40 static bool
  41 MPD_ERROR(const struct mpdclient *client)
  42 {
  43         return client->connection == NULL ||
  44                 mpd_connection_get_error(client->connection) != MPD_ERROR_SUCCESS;
  45 }
  46
  47 /* filelist sorting functions */
  48 static gint
  49 compare_filelistentry(gconstpointer filelist_entry1,
  50                           gconstpointer filelist_entry2)
  51 {
  52         const struct mpd_entity *e1, *e2;
  53         int n = 0;
  54
  55         e1 = ((const struct filelist_entry *)filelist_entry1)->entity;
  56         e2 = ((const struct filelist_entry *)filelist_entry2)->entity;
  57
  58         if (e1 != NULL && e2 != NULL &&
  59             mpd_entity_get_type(e1) == mpd_entity_get_type(e2)) {
  60                 switch (mpd_entity_get_type(e1)) {
  61                 case MPD_ENTITY_TYPE_UNKNOWN:
  62                         break;
  63                 case MPD_ENTITY_TYPE_DIRECTORY:
  64                         n = g_utf8_collate(mpd_directory_get_path(mpd_entity_get_directory(e1)),
  65                                            mpd_directory_get_path(mpd_entity_get_directory(e2)));
  66                         break;
  67                 case MPD_ENTITY_TYPE_SONG:
  68                         break;
  69                 case MPD_ENTITY_TYPE_PLAYLIST:
  70                         n = g_utf8_collate(mpd_playlist_get_path(mpd_entity_get_playlist(e1)),
  71                                            mpd_playlist_get_path(mpd_entity_get_playlist(e2)));
  72                 }
  73         }
  74         return n;
  75 }
  76
  77 /* sort by list-format */
  78 gint
  79 compare_filelistentry_format(gconstpointer filelist_entry1,
  80                              gconstpointer filelist_entry2)
  81 {
  82         const struct mpd_entity *e1, *e2;
  83         char key1[BUFSIZE], key2[BUFSIZE];
  84         int n = 0;
  85
  86         e1 = ((const struct filelist_entry *)filelist_entry1)->entity;
  87         e2 = ((const struct filelist_entry *)filelist_entry2)->entity;
  88
  89         if (e1 && e2 &&
  90             mpd_entity_get_type(e1) == MPD_ENTITY_TYPE_SONG &&
  91             mpd_entity_get_type(e2) == MPD_ENTITY_TYPE_SONG) {
  92                 strfsong(key1, BUFSIZE, options.list_format, mpd_entity_get_song(e1));
  93                 strfsong(key2, BUFSIZE, options.list_format, mpd_entity_get_song(e2));
  94                 n = strcmp(key1,key2);
  95         }
  96
  97         return n;
  98 }
  99
 100
 101 /****************************************************************************/
 102 /*** mpdclient functions ****************************************************/
 103 /****************************************************************************/
 104
 105 gint
 106 mpdclient_handle_error(struct mpdclient *c)
 107 {
 108         enum mpd_error error = mpd_connection_get_error(c->connection);
 109
 110         assert(error != MPD_ERROR_SUCCESS);
 111
 112         if (error == MPD_ERROR_SERVER &&
 113             mpd_connection_get_server_error(c->connection) == MPD_SERVER_ERROR_PERMISSION &&
 114             screen_auth(c))
 115                 return 0;
 116
 117         if (error == MPD_ERROR_SERVER)
 118                 error = error | (mpd_connection_get_server_error(c->connection) << 8);
 119
 120         mpdclient_ui_error(mpd_connection_get_error_message(c->connection));
 121
 122         if (!mpd_connection_clear_error(c->connection))
 123                 mpdclient_disconnect(c);
 124
 125         return error;
 126 }
 127
 128 static gint
 129 mpdclient_finish_command(struct mpdclient *c)
 130 {
 131         return mpd_response_finish(c->connection)
 132                 ? 0 : mpdclient_handle_error(c);
 133 }
 134
 135 struct mpdclient *
 136 mpdclient_new(void)
 137 {
 138         struct mpdclient *c;
 139
 140         c = g_new0(struct mpdclient, 1);
 141         playlist_init(&c->playlist);
 142         c->volume = -1;
 143         c->events = 0;
 144
 145         return c;
 146 }
 147
 148 void
 149 mpdclient_free(struct mpdclient *c)
 150 {
 151         mpdclient_disconnect(c);
 152
 153         mpdclient_playlist_free(&c->playlist);
 154
 155         g_free(c);
 156 }
 157
 158 void
 159 mpdclient_disconnect(struct mpdclient *c)
 160 {
 161         if (c->connection)
 162                 mpd_connection_free(c->connection);
 163         c->connection = NULL;
 164
 165         if (c->status)
 166                 mpd_status_free(c->status);
 167         c->status = NULL;
 168
 169         playlist_clear(&c->playlist);
 170
 171         if (c->song)
 172                 c->song = NULL;
 173 }
 174
 175 bool
 176 mpdclient_connect(struct mpdclient *c,
 177                   const gchar *host,
 178                   gint port,
 179                   gfloat _timeout,
 180                   const gchar *password)
 181 {
 182         /* close any open connection */
 183         if( c->connection )
 184                 mpdclient_disconnect(c);
 185
 186         /* connect to MPD */
 187         c->connection = mpd_connection_new(host, port, _timeout * 1000);
 188         if (c->connection == NULL)
 189                 g_error("Out of memory");
 190
 191         if (mpd_connection_get_error(c->connection) != MPD_ERROR_SUCCESS) {
 192                 mpdclient_handle_error(c);
 193                 mpdclient_disconnect(c);
 194                 return false;
 195         }
 196
 197         /* send password */
 198         if (password != NULL && !mpd_run_password(c->connection, password)) {
 199                 mpdclient_handle_error(c);
 200                 mpdclient_disconnect(c);
 201                 return false;
 202         }
 203
 204         return true;
 205 }
 206
 207 bool
 208 mpdclient_update(struct mpdclient *c)
 209 {
 210         bool retval;
 211
 212         c->volume = -1;
 213
 214         if (MPD_ERROR(c))
 215                 return false;
 216
 217         /* always announce these options as long as we don't have real
 218            "idle" support */
 219         c->events |= MPD_IDLE_PLAYER|MPD_IDLE_OPTIONS;
 220
 221         /* free the old status */
 222         if (c->status)
 223                 mpd_status_free(c->status);
 224
 225         /* retrieve new status */
 226         c->status = mpd_run_status(c->connection);
 227         if (c->status == NULL)
 228                 return mpdclient_handle_error(c) == 0;
 229
 230         if (c->update_id != mpd_status_get_update_id(c->status)) {
 231                 c->events |= MPD_IDLE_UPDATE;
 232
 233                 if (c->update_id > 0)
 234                         c->events |= MPD_IDLE_DATABASE;
 235         }
 236
 237         c->update_id = mpd_status_get_update_id(c->status);
 238
 239         if (c->volume != mpd_status_get_volume(c->status))
 240                 c->events |= MPD_IDLE_MIXER;
 241
 242         c->volume = mpd_status_get_volume(c->status);
 243
 244         /* check if the playlist needs an update */
 245         if (c->playlist.version != mpd_status_get_queue_version(c->status)) {
 246                 c->events |= MPD_IDLE_PLAYLIST;
 247
 248                 if (!playlist_is_empty(&c->playlist))
 249                         retval = mpdclient_playlist_update_changes(c);
 250                 else
 251                         retval = mpdclient_playlist_update(c);
 252         } else
 253                 retval = true;
 254
 255         /* update the current song */
 256         if (!c->song || mpd_status_get_song_id(c->status)) {
 257                 c->song = playlist_get_song(&c->playlist,
 258                                             mpd_status_get_song_pos(c->status));
 259         }
 260
 261         return retval;
 262 }
 263
 264
 265 /****************************************************************************/
 266 /*** MPD Commands  **********************************************************/
 267 /****************************************************************************/
 268
 269 gint
 270 mpdclient_cmd_play(struct mpdclient *c, gint idx)
 271 {
 272         const struct mpd_song *song = playlist_get_song(&c->playlist, idx);
 273
 274         if (MPD_ERROR(c))
 275                 return -1;
 276
 277         if (song)
 278                 mpd_send_play_id(c->connection, mpd_song_get_id(song));
 279         else
 280                 mpd_send_play(c->connection);
 281
 282         return mpdclient_finish_command(c);
 283 }
 284
 285 gint
 286 mpdclient_cmd_crop(struct mpdclient *c)
 287 {
 288         struct mpd_status *status;
 289         bool playing;
 290         int length, current;
 291
 292         if (MPD_ERROR(c))
 293                 return -1;
 294
 295         status = mpd_run_status(c->connection);
 296         if (status == NULL)
 297                 return mpdclient_handle_error(c);
 298
 299         playing = mpd_status_get_state(status) == MPD_STATE_PLAY ||
 300                 mpd_status_get_state(status) == MPD_STATE_PAUSE;
 301         length = mpd_status_get_queue_length(status);
 302         current = mpd_status_get_song_pos(status);
 303
 304         mpd_status_free(status);
 305
 306         if (!playing || length < 2)
 307                 return 0;
 308
 309         mpd_command_list_begin(c->connection, false);
 310
 311         while (--length >= 0)
 312                 if (length != current)
 313                         mpd_send_delete(c->connection, length);
 314
 315         mpd_command_list_end(c->connection);
 316
 317         return mpdclient_finish_command(c);
 318 }
 319
 320 gint
 321 mpdclient_cmd_shuffle_range(struct mpdclient *c, guint start, guint end)
 322 {
 323         mpd_send_shuffle_range(c->connection, start, end);
 324         return mpdclient_finish_command(c);
 325 }
 326
 327 gint
 328 mpdclient_cmd_clear(struct mpdclient *c)
 329 {
 330         gint retval = 0;
 331
 332         if (MPD_ERROR(c))
 333                 return -1;
 334
 335         mpd_send_clear(c->connection);
 336         retval = mpdclient_finish_command(c);
 337
 338         if (retval)
 339                 c->events |= MPD_IDLE_PLAYLIST;
 340
 341         return retval;
 342 }
 343
 344 gint
 345 mpdclient_cmd_volume(struct mpdclient *c, gint value)
 346 {
 347         if (MPD_ERROR(c))
 348                 return -1;
 349
 350         mpd_send_set_volume(c->connection, value);
 351         return mpdclient_finish_command(c);
 352 }
 353
 354 gint mpdclient_cmd_volume_up(struct mpdclient *c)
 355 {
 356         if (MPD_ERROR(c))
 357                 return -1;
 358
 359         if (c->status == NULL ||
 360             mpd_status_get_volume(c->status) == -1)
 361                 return 0;
 362
 363         if (c->volume < 0)
 364                 c->volume = mpd_status_get_volume(c->status);
 365
 366         if (c->volume >= 100)
 367                 return 0;
 368
 369         return mpdclient_cmd_volume(c, ++c->volume);
 370 }
 371
 372 gint mpdclient_cmd_volume_down(struct mpdclient *c)
 373 {
 374         if (MPD_ERROR(c))
 375                 return -1;
 376
 377         if (c->status == NULL || mpd_status_get_volume(c->status) < 0)
 378                 return 0;
 379
 380         if (c->volume < 0)
 381                 c->volume = mpd_status_get_volume(c->status);
 382
 383         if (c->volume <= 0)
 384                 return 0;
 385
 386         return mpdclient_cmd_volume(c, --c->volume);
 387 }
 388
 389 gint
 390 mpdclient_cmd_add_path(struct mpdclient *c, const gchar *path_utf8)
 391 {
 392         if (MPD_ERROR(c))
 393                 return -1;
 394
 395         mpd_send_add(c->connection, path_utf8);
 396         return mpdclient_finish_command(c);
 397 }
 398
 399 gint
 400 mpdclient_cmd_add(struct mpdclient *c, const struct mpd_song *song)
 401 {
 402         struct mpd_status *status;
 403         struct mpd_song *new_song;
 404
 405         assert(c != NULL);
 406         assert(song != NULL);
 407
 408         if (MPD_ERROR(c) || c->status == NULL)
 409                 return -1;
 410
 411         /* send the add command to mpd; at the same time, get the new
 412            status (to verify the new playlist id) and the last song
 413            (we hope that's the song we just added) */
 414
 415         if (!mpd_command_list_begin(c->connection, true) ||
 416             !mpd_send_add(c->connection, mpd_song_get_uri(song)) ||
 417             !mpd_send_status(c->connection) ||
 418             !mpd_send_get_queue_song_pos(c->connection,
 419                                          playlist_length(&c->playlist)) ||
 420             !mpd_command_list_end(c->connection) ||
 421             !mpd_response_next(c->connection))
 422                 return mpdclient_handle_error(c);
 423
 424         c->events |= MPD_IDLE_PLAYLIST;
 425
 426         status = mpd_recv_status(c->connection);
 427         if (status != NULL) {
 428                 if (c->status != NULL)
 429                         mpd_status_free(c->status);
 430                 c->status = status;
 431         }
 432
 433         if (!mpd_response_next(c->connection))
 434                 return mpdclient_handle_error(c);
 435
 436         new_song = mpd_recv_song(c->connection);
 437         if (!mpd_response_finish(c->connection) || new_song == NULL) {
 438                 if (new_song != NULL)
 439                         mpd_song_free(new_song);
 440
 441                 return mpd_connection_clear_error(c->connection)
 442                         ? 0 : mpdclient_handle_error(c);
 443         }
 444
 445         if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) + 1 &&
 446             mpd_status_get_queue_version(status) == c->playlist.version + 1) {
 447                 /* the cheap route: match on the new playlist length
 448                    and its version, we can keep our local playlist
 449                    copy in sync */
 450                 c->playlist.version = mpd_status_get_queue_version(status);
 451
 452                 /* the song we just received has the correct id;
 453                    append it to the local playlist */
 454                 playlist_append(&c->playlist, new_song);
 455         }
 456
 457         mpd_song_free(new_song);
 458
 459         return -0;
 460 }
 461
 462 gint
 463 mpdclient_cmd_delete(struct mpdclient *c, gint idx)
 464 {
 465         gint retval = 0;
 466         struct mpd_song *song;
 467
 468         if (MPD_ERROR(c))
 469                 return -1;
 470
 471         if (idx < 0 || (guint)idx >= playlist_length(&c->playlist))
 472                 return -1;
 473
 474         song = playlist_get(&c->playlist, idx);
 475
 476         /* send the delete command to mpd */
 477         mpd_send_delete_id(c->connection, mpd_song_get_id(song));
 478         if( (retval=mpdclient_finish_command(c)) )
 479                 return retval;
 480
 481 #ifdef ENABLE_FANCY_PLAYLIST_MANAGMENT_CMD_DELETE
 482         /* increment the playlist id, so we don't retrieve a new playlist */
 483         c->playlist.version++;
 484
 485         /* remove the song from the playlist */
 486         playlist_remove_reuse(&c->playlist, idx);
 487
 488         c->events |= MPD_IDLE_PLAYLIST;
 489
 490         /* remove references to the song */
 491         if (c->song == song)
 492                 c->song = NULL;
 493
 494         mpd_song_free(song);
 495 #endif
 496
 497         return 0;
 498 }
 499
 500 gint
 501 mpdclient_cmd_move(struct mpdclient *c, gint old_index, gint new_index)
 502 {
 503         gint n;
 504         struct mpd_song *song1, *song2;
 505
 506         if (MPD_ERROR(c))
 507                 return -1;
 508
 509         if (old_index == new_index || new_index < 0 ||
 510             (guint)new_index >= c->playlist.list->len)
 511                 return -1;
 512
 513         song1 = playlist_get(&c->playlist, old_index);
 514         song2 = playlist_get(&c->playlist, new_index);
 515
 516         /* send the move command to mpd */
 517         mpd_send_swap_id(c->connection,
 518                          mpd_song_get_id(song1), mpd_song_get_id(song2));
 519         if( (n=mpdclient_finish_command(c)) )
 520                 return n;
 521
 522 #ifdef ENABLE_FANCY_PLAYLIST_MANAGMENT_CMD_MOVE
 523         /* update the playlist */
 524         playlist_swap(&c->playlist, old_index, new_index);
 525
 526         /* increment the playlist id, so we don't retrieve a new playlist */
 527         c->playlist.version++;
 528 #endif
 529
 530         c->events |= MPD_IDLE_PLAYLIST;
 531
 532         return 0;
 533 }
 534
 535 gint
 536 mpdclient_cmd_save_playlist(struct mpdclient *c, const gchar *filename_utf8)
 537 {
 538         gint retval = 0;
 539
 540         if (MPD_ERROR(c))
 541                 return -1;
 542
 543         mpd_send_save(c->connection, filename_utf8);
 544         if ((retval = mpdclient_finish_command(c)) == 0) {
 545                 c->events |= MPD_IDLE_STORED_PLAYLIST;
 546         }
 547
 548         return retval;
 549 }
 550
 551 gint
 552 mpdclient_cmd_load_playlist(struct mpdclient *c, const gchar *filename_utf8)
 553 {
 554         if (MPD_ERROR(c))
 555                 return -1;
 556
 557         mpd_send_load(c->connection, filename_utf8);
 558         return mpdclient_finish_command(c);
 559 }
 560
 561 gint
 562 mpdclient_cmd_delete_playlist(struct mpdclient *c, const gchar *filename_utf8)
 563 {
 564         gint retval = 0;
 565
 566         if (MPD_ERROR(c))
 567                 return -1;
 568
 569         mpd_send_rm(c->connection, filename_utf8);
 570         if ((retval = mpdclient_finish_command(c)) == 0)
 571                 c->events |= MPD_IDLE_STORED_PLAYLIST;
 572
 573         return retval;
 574 }
 575
 576
 577 /****************************************************************************/
 578 /*** Playlist management functions ******************************************/
 579 /****************************************************************************/
 580
 581 /* update playlist */
 582 bool
 583 mpdclient_playlist_update(struct mpdclient *c)
 584 {
 585         struct mpd_entity *entity;
 586
 587         if (MPD_ERROR(c))
 588                 return false;
 589
 590         playlist_clear(&c->playlist);
 591
 592         mpd_send_list_queue_meta(c->connection);
 593         while ((entity = mpd_recv_entity(c->connection))) {
 594                 if (mpd_entity_get_type(entity) == MPD_ENTITY_TYPE_SONG)
 595                         playlist_append(&c->playlist, mpd_entity_get_song(entity));
 596
 597                 mpd_entity_free(entity);
 598         }
 599
 600         c->playlist.version = mpd_status_get_queue_version(c->status);
 601         c->song = NULL;
 602
 603         return mpdclient_finish_command(c) == 0;
 604 }
 605
 606 /* update playlist (plchanges) */
 607 bool
 608 mpdclient_playlist_update_changes(struct mpdclient *c)
 609 {
 610         struct mpd_song *song;
 611         guint length;
 612
 613         if (MPD_ERROR(c))
 614                 return false;
 615
 616         mpd_send_queue_changes_meta(c->connection, c->playlist.version);
 617
 618         while ((song = mpd_recv_song(c->connection)) != NULL) {
 619                 int pos = mpd_song_get_pos(song);
 620
 621                 if (pos >= 0 && (guint)pos < c->playlist.list->len) {
 622                         /* update song */
 623                         playlist_replace(&c->playlist, pos, song);
 624                 } else {
 625                         /* add a new song */
 626                         playlist_append(&c->playlist, song);
 627                 }
 628
 629                 mpd_song_free(song);
 630         }
 631
 632         /* remove trailing songs */
 633
 634         length = mpd_status_get_queue_length(c->status);
 635         while (length < c->playlist.list->len) {
 636                 guint pos = c->playlist.list->len - 1;
 637
 638                 /* Remove the last playlist entry */
 639                 playlist_remove(&c->playlist, pos);
 640         }
 641
 642         c->song = NULL;
 643         c->playlist.version = mpd_status_get_queue_version(c->status);
 644
 645         return mpdclient_finish_command(c) == 0;
 646 }
 647
 648
 649 /****************************************************************************/
 650 /*** Filelist functions *****************************************************/
 651 /****************************************************************************/
 652
 653 struct filelist *
 654 mpdclient_filelist_get(struct mpdclient *c, const gchar *path)
 655 {
 656         struct filelist *filelist;
 657         struct mpd_entity *entity;
 658
 659         if (MPD_ERROR(c))
 660                 return NULL;
 661
 662         mpd_send_list_meta(c->connection, path);
 663         filelist = filelist_new();
 664
 665         while ((entity = mpd_recv_entity(c->connection)) != NULL)
 666                 filelist_append(filelist, entity);
 667
 668         if (mpdclient_finish_command(c)) {
 669                 filelist_free(filelist);
 670                 return NULL;
 671         }
 672
 673         filelist_sort_dir_play(filelist, compare_filelistentry);
 674
 675         return filelist;
 676 }
 677
 678 static struct filelist *
 679 mpdclient_recv_filelist_response(struct mpdclient *c)
 680 {
 681         struct filelist *filelist;
 682         struct mpd_entity *entity;
 683
 684         filelist = filelist_new();
 685
 686         while ((entity = mpd_recv_entity(c->connection)) != NULL)
 687                 filelist_append(filelist, entity);
 688
 689         if (mpdclient_finish_command(c)) {
 690                 filelist_free(filelist);
 691                 return NULL;
 692         }
 693
 694         return filelist;
 695 }
 696
 697 struct filelist *
 698 mpdclient_filelist_search(struct mpdclient *c,
 699                           int exact_match,
 700                           enum mpd_tag_type tag,
 701                           gchar *filter_utf8)
 702 {
 703         if (MPD_ERROR(c))
 704                 return NULL;
 705
 706         mpd_search_db_songs(c->connection, exact_match);
 707         mpd_search_add_tag_constraint(c->connection, MPD_OPERATOR_DEFAULT,
 708                                       tag, filter_utf8);
 709         mpd_search_commit(c->connection);
 710
 711         return mpdclient_recv_filelist_response(c);
 712 }
 713
 714 int
 715 mpdclient_filelist_add_all(struct mpdclient *c, struct filelist *fl)
 716 {
 717         guint i;
 718
 719         if (MPD_ERROR(c))
 720                 return -1;
 721
 722         if (filelist_is_empty(fl))
 723                 return 0;
 724
 725         mpd_command_list_begin(c->connection, false);
 726
 727         for (i = 0; i < filelist_length(fl); ++i) {
 728                 struct filelist_entry *entry = filelist_get(fl, i);
 729                 struct mpd_entity *entity  = entry->entity;
 730
 731                 if (entity != NULL &&
 732                     mpd_entity_get_type(entity) == MPD_ENTITY_TYPE_SONG) {
 733                         const struct mpd_song *song =
 734                                 mpd_entity_get_song(entity);
 735                         const char *uri = mpd_song_get_uri(song);
 736
 737                         if (uri != NULL)
 738                                 mpd_send_add(c->connection, uri);
 739                 }
 740         }
 741
 742         mpd_command_list_end(c->connection);
 743         return mpdclient_finish_command(c);
 744 }
 745
 746 GList *
 747 mpdclient_get_artists(struct mpdclient *c)
 748 {
 749         GList *list = NULL;
 750         struct mpd_pair *pair;
 751
 752         if (MPD_ERROR(c))
 753                return NULL;
 754
 755         mpd_search_db_tags(c->connection, MPD_TAG_ARTIST);
 756         mpd_search_commit(c->connection);
 757
 758         while ((pair = mpd_recv_pair_tag(c->connection,
 759                                          MPD_TAG_ARTIST)) != NULL) {
 760                 list = g_list_append(list, g_strdup(pair->value));
 761                 mpd_return_pair(c->connection, pair);
 762         }
 763
 764         if (mpdclient_finish_command(c))
 765                 return string_list_free(list);
 766
 767         return list;
 768 }
 769
 770 GList *
 771 mpdclient_get_albums(struct mpdclient *c, const gchar *artist_utf8)
 772 {
 773         GList *list = NULL;
 774         struct mpd_pair *pair;
 775
 776         if (MPD_ERROR(c))
 777                return NULL;
 778
 779         mpd_search_db_tags(c->connection, MPD_TAG_ALBUM);
 780         if (artist_utf8 != NULL)
 781                 mpd_search_add_tag_constraint(c->connection,
 782                                               MPD_OPERATOR_DEFAULT,
 783                                               MPD_TAG_ARTIST, artist_utf8);
 784         mpd_search_commit(c->connection);
 785
 786         while ((pair = mpd_recv_pair_tag(c->connection,
 787                                          MPD_TAG_ALBUM)) != NULL) {
 788                 list = g_list_append(list, g_strdup(pair->value));
 789                 mpd_return_pair(c->connection, pair);
 790         }
 791
 792         if (mpdclient_finish_command(c))
 793                 return string_list_free(list);
 794
 795         return list;
 796 }