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 #include "gidle.h"
  28
  29 #include <mpd/client.h>
  30
  31 #include <stdlib.h>
  32 #include <unistd.h>
  33 #include <time.h>
  34 #include <string.h>
  35
  36 #define BUFSIZE 1024
  37
  38 /* sort by list-format */
  39 gint
  40 compare_filelistentry_format(gconstpointer filelist_entry1,
  41                              gconstpointer filelist_entry2)
  42 {
  43         const struct mpd_entity *e1, *e2;
  44         char key1[BUFSIZE], key2[BUFSIZE];
  45         int n = 0;
  46
  47         e1 = ((const struct filelist_entry *)filelist_entry1)->entity;
  48         e2 = ((const struct filelist_entry *)filelist_entry2)->entity;
  49
  50         if (e1 && e2 &&
  51             mpd_entity_get_type(e1) == MPD_ENTITY_TYPE_SONG &&
  52             mpd_entity_get_type(e2) == MPD_ENTITY_TYPE_SONG) {
  53                 strfsong(key1, BUFSIZE, options.list_format, mpd_entity_get_song(e1));
  54                 strfsong(key2, BUFSIZE, options.list_format, mpd_entity_get_song(e2));
  55                 n = strcmp(key1,key2);
  56         }
  57
  58         return n;
  59 }
  60
  61
  62 /****************************************************************************/
  63 /*** mpdclient functions ****************************************************/
  64 /****************************************************************************/
  65
  66 bool
  67 mpdclient_handle_error(struct mpdclient *c)
  68 {
  69         enum mpd_error error = mpd_connection_get_error(c->connection);
  70
  71         assert(error != MPD_ERROR_SUCCESS);
  72
  73         if (error == MPD_ERROR_SERVER &&
  74             mpd_connection_get_server_error(c->connection) == MPD_SERVER_ERROR_PERMISSION &&
  75             screen_auth(c))
  76                 return true;
  77
  78         mpdclient_ui_error(mpd_connection_get_error_message(c->connection));
  79
  80         if (!mpd_connection_clear_error(c->connection))
  81                 mpdclient_disconnect(c);
  82
  83         return false;
  84 }
  85
  86 static bool
  87 mpdclient_finish_command(struct mpdclient *c)
  88 {
  89         return mpd_response_finish(c->connection)
  90                 ? true : mpdclient_handle_error(c);
  91 }
  92
  93 struct mpdclient *
  94 mpdclient_new(void)
  95 {
  96         struct mpdclient *c;
  97
  98         c = g_new0(struct mpdclient, 1);
  99         playlist_init(&c->playlist);
 100         c->volume = -1;
 101         c->events = 0;
 102
 103         return c;
 104 }
 105
 106 void
 107 mpdclient_free(struct mpdclient *c)
 108 {
 109         mpdclient_disconnect(c);
 110
 111         mpdclient_playlist_free(&c->playlist);
 112
 113         g_free(c);
 114 }
 115
 116 void
 117 mpdclient_disconnect(struct mpdclient *c)
 118 {
 119         if (c->source != NULL) {
 120                 mpd_glib_free(c->source);
 121                 c->source = NULL;
 122                 c->idle = false;
 123         }
 124
 125         if (c->connection)
 126                 mpd_connection_free(c->connection);
 127         c->connection = NULL;
 128
 129         if (c->status)
 130                 mpd_status_free(c->status);
 131         c->status = NULL;
 132
 133         playlist_clear(&c->playlist);
 134
 135         if (c->song)
 136                 c->song = NULL;
 137
 138         /* everything has changed after a disconnect */
 139         c->idle |= MPD_IDLE_DATABASE|MPD_IDLE_STORED_PLAYLIST|
 140                 MPD_IDLE_QUEUE|MPD_IDLE_PLAYER|MPD_IDLE_MIXER|MPD_IDLE_OUTPUT|
 141                 MPD_IDLE_OPTIONS|MPD_IDLE_UPDATE;
 142 }
 143
 144 bool
 145 mpdclient_connect(struct mpdclient *c,
 146                   const gchar *host,
 147                   gint port,
 148                   gfloat _timeout,
 149                   const gchar *password)
 150 {
 151         /* close any open connection */
 152         if( c->connection )
 153                 mpdclient_disconnect(c);
 154
 155         /* connect to MPD */
 156         c->connection = mpd_connection_new(host, port, _timeout * 1000);
 157         if (c->connection == NULL)
 158                 g_error("Out of memory");
 159
 160         if (mpd_connection_get_error(c->connection) != MPD_ERROR_SUCCESS) {
 161                 mpdclient_handle_error(c);
 162                 mpdclient_disconnect(c);
 163                 return false;
 164         }
 165
 166         /* send password */
 167         if (password != NULL && !mpd_run_password(c->connection, password)) {
 168                 mpdclient_handle_error(c);
 169                 mpdclient_disconnect(c);
 170                 return false;
 171         }
 172
 173         return true;
 174 }
 175
 176 bool
 177 mpdclient_update(struct mpdclient *c)
 178 {
 179         struct mpd_connection *connection = mpdclient_get_connection(c);
 180         bool retval;
 181
 182         c->volume = -1;
 183
 184         if (connection == NULL)
 185                 return false;
 186
 187         /* always announce these options as long as we don't have
 188            "idle" support */
 189         if (c->source == NULL)
 190                 c->events |= MPD_IDLE_PLAYER|MPD_IDLE_OPTIONS;
 191
 192         /* free the old status */
 193         if (c->status)
 194                 mpd_status_free(c->status);
 195
 196         /* retrieve new status */
 197         c->status = mpd_run_status(connection);
 198         if (c->status == NULL)
 199                 return mpdclient_handle_error(c);
 200
 201         if (c->source == NULL &&
 202             c->update_id != mpd_status_get_update_id(c->status)) {
 203                 c->events |= MPD_IDLE_UPDATE;
 204
 205                 if (c->update_id > 0)
 206                         c->events |= MPD_IDLE_DATABASE;
 207         }
 208
 209         c->update_id = mpd_status_get_update_id(c->status);
 210
 211         if (c->source == NULL &&
 212             c->volume != mpd_status_get_volume(c->status))
 213                 c->events |= MPD_IDLE_MIXER;
 214
 215         c->volume = mpd_status_get_volume(c->status);
 216
 217         /* check if the playlist needs an update */
 218         if (c->playlist.version != mpd_status_get_queue_version(c->status)) {
 219                 if (c->source == NULL)
 220                         c->events |= MPD_IDLE_PLAYLIST;
 221
 222                 if (!playlist_is_empty(&c->playlist))
 223                         retval = mpdclient_playlist_update_changes(c);
 224                 else
 225                         retval = mpdclient_playlist_update(c);
 226         } else
 227                 retval = true;
 228
 229         /* update the current song */
 230         if (!c->song || mpd_status_get_song_id(c->status)) {
 231                 c->song = playlist_get_song(&c->playlist,
 232                                             mpd_status_get_song_pos(c->status));
 233         }
 234
 235         return retval;
 236 }
 237
 238 struct mpd_connection *
 239 mpdclient_get_connection(struct mpdclient *c)
 240 {
 241         if (c->source != NULL && c->idle) {
 242                 c->idle = false;
 243                 mpd_glib_leave(c->source);
 244         }
 245
 246         return c->connection;
 247 }
 248
 249 void
 250 mpdclient_put_connection(struct mpdclient *c)
 251 {
 252         assert(c->source == NULL || c->connection != NULL);
 253
 254         if (c->source != NULL && !c->idle) {
 255                 c->idle = true;
 256                 mpd_glib_enter(c->source);
 257         }
 258 }
 259
 260
 261 /****************************************************************************/
 262 /*** MPD Commands  **********************************************************/
 263 /****************************************************************************/
 264
 265 bool
 266 mpdclient_cmd_play(struct mpdclient *c, gint idx)
 267 {
 268         struct mpd_connection *connection = mpdclient_get_connection(c);
 269         const struct mpd_song *song = playlist_get_song(&c->playlist, idx);
 270
 271         if (connection == NULL)
 272                 return false;
 273
 274         if (song)
 275                 mpd_send_play_id(connection, mpd_song_get_id(song));
 276         else
 277                 mpd_send_play(connection);
 278
 279         return mpdclient_finish_command(c);
 280 }
 281
 282 bool
 283 mpdclient_cmd_crop(struct mpdclient *c)
 284 {
 285         struct mpd_connection *connection = mpdclient_get_connection(c);
 286         struct mpd_status *status;
 287         bool playing;
 288         int length, current;
 289
 290         if (connection == NULL)
 291                 return false;
 292
 293         status = mpd_run_status(connection);
 294         if (status == NULL)
 295                 return mpdclient_handle_error(c);
 296
 297         playing = mpd_status_get_state(status) == MPD_STATE_PLAY ||
 298                 mpd_status_get_state(status) == MPD_STATE_PAUSE;
 299         length = mpd_status_get_queue_length(status);
 300         current = mpd_status_get_song_pos(status);
 301
 302         mpd_status_free(status);
 303
 304         if (!playing || length < 2)
 305                 return true;
 306
 307         mpd_command_list_begin(connection, false);
 308
 309         while (--length >= 0)
 310                 if (length != current)
 311                         mpd_send_delete(connection, length);
 312
 313         mpd_command_list_end(connection);
 314
 315         return mpdclient_finish_command(c);
 316 }
 317
 318 bool
 319 mpdclient_cmd_clear(struct mpdclient *c)
 320 {
 321         struct mpd_connection *connection = mpdclient_get_connection(c);
 322         bool retval;
 323
 324         if (connection == NULL)
 325                 return false;
 326
 327         mpd_send_clear(connection);
 328         retval = mpdclient_finish_command(c);
 329
 330         if (retval)
 331                 c->events |= MPD_IDLE_PLAYLIST;
 332
 333         return retval;
 334 }
 335
 336 bool
 337 mpdclient_cmd_volume(struct mpdclient *c, gint value)
 338 {
 339         struct mpd_connection *connection = mpdclient_get_connection(c);
 340         if (connection == NULL)
 341                 return false;
 342
 343         mpd_send_set_volume(connection, value);
 344         return mpdclient_finish_command(c);
 345 }
 346
 347 bool
 348 mpdclient_cmd_volume_up(struct mpdclient *c)
 349 {
 350         struct mpd_connection *connection = mpdclient_get_connection(c);
 351         if (connection == NULL)
 352                 return false;
 353
 354         if (c->status == NULL ||
 355             mpd_status_get_volume(c->status) == -1)
 356                 return true;
 357
 358         if (c->volume < 0)
 359                 c->volume = mpd_status_get_volume(c->status);
 360
 361         if (c->volume >= 100)
 362                 return true;
 363
 364         return mpdclient_cmd_volume(c, ++c->volume);
 365 }
 366
 367 bool
 368 mpdclient_cmd_volume_down(struct mpdclient *c)
 369 {
 370         struct mpd_connection *connection = mpdclient_get_connection(c);
 371         if (connection == NULL)
 372                 return false;
 373
 374         if (c->status == NULL || mpd_status_get_volume(c->status) < 0)
 375                 return true;
 376
 377         if (c->volume < 0)
 378                 c->volume = mpd_status_get_volume(c->status);
 379
 380         if (c->volume <= 0)
 381                 return true;
 382
 383         return mpdclient_cmd_volume(c, --c->volume);
 384 }
 385
 386 bool
 387 mpdclient_cmd_add_path(struct mpdclient *c, const gchar *path_utf8)
 388 {
 389         struct mpd_connection *connection = mpdclient_get_connection(c);
 390         if (connection == NULL)
 391                 return false;
 392
 393         mpd_send_add(connection, path_utf8);
 394         return mpdclient_finish_command(c);
 395 }
 396
 397 bool
 398 mpdclient_cmd_add(struct mpdclient *c, const struct mpd_song *song)
 399 {
 400         struct mpd_connection *connection = mpdclient_get_connection(c);
 401         struct mpd_status *status;
 402         struct mpd_song *new_song;
 403
 404         assert(c != NULL);
 405         assert(song != NULL);
 406
 407         if (connection == NULL || c->status == NULL)
 408                 return false;
 409
 410         /* send the add command to mpd; at the same time, get the new
 411            status (to verify the new playlist id) and the last song
 412            (we hope that's the song we just added) */
 413
 414         if (!mpd_command_list_begin(connection, true) ||
 415             !mpd_send_add(connection, mpd_song_get_uri(song)) ||
 416             !mpd_send_status(connection) ||
 417             !mpd_send_get_queue_song_pos(connection,
 418                                          playlist_length(&c->playlist)) ||
 419             !mpd_command_list_end(connection) ||
 420             !mpd_response_next(connection))
 421                 return mpdclient_handle_error(c);
 422
 423         c->events |= MPD_IDLE_PLAYLIST;
 424
 425         status = mpd_recv_status(connection);
 426         if (status != NULL) {
 427                 if (c->status != NULL)
 428                         mpd_status_free(c->status);
 429                 c->status = status;
 430         }
 431
 432         if (!mpd_response_next(connection))
 433                 return mpdclient_handle_error(c);
 434
 435         new_song = mpd_recv_song(connection);
 436         if (!mpd_response_finish(connection) || new_song == NULL) {
 437                 if (new_song != NULL)
 438                         mpd_song_free(new_song);
 439
 440                 return mpd_connection_clear_error(connection) ||
 441                         mpdclient_handle_error(c);
 442         }
 443
 444         if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) + 1 &&
 445             mpd_status_get_queue_version(status) == c->playlist.version + 1) {
 446                 /* the cheap route: match on the new playlist length
 447                    and its version, we can keep our local playlist
 448                    copy in sync */
 449                 c->playlist.version = mpd_status_get_queue_version(status);
 450
 451                 /* the song we just received has the correct id;
 452                    append it to the local playlist */
 453                 playlist_append(&c->playlist, new_song);
 454         }
 455
 456         mpd_song_free(new_song);
 457
 458         return true;
 459 }
 460
 461 bool
 462 mpdclient_cmd_delete(struct mpdclient *c, gint idx)
 463 {
 464         struct mpd_connection *connection = mpdclient_get_connection(c);
 465         const struct mpd_song *song;
 466         struct mpd_status *status;
 467
 468         if (connection == NULL || c->status == NULL)
 469                 return false;
 470
 471         if (idx < 0 || (guint)idx >= playlist_length(&c->playlist))
 472                 return false;
 473
 474         song = playlist_get(&c->playlist, idx);
 475
 476         /* send the delete command to mpd; at the same time, get the
 477            new status (to verify the playlist id) */
 478
 479         if (!mpd_command_list_begin(connection, false) ||
 480             !mpd_send_delete_id(connection, mpd_song_get_id(song)) ||
 481             !mpd_send_status(connection) ||
 482             !mpd_command_list_end(connection))
 483                 return mpdclient_handle_error(c);
 484
 485         c->events |= MPD_IDLE_PLAYLIST;
 486
 487         status = mpd_recv_status(connection);
 488         if (status != NULL) {
 489                 if (c->status != NULL)
 490                         mpd_status_free(c->status);
 491                 c->status = status;
 492         }
 493
 494         if (!mpd_response_finish(connection))
 495                 return mpdclient_handle_error(c);
 496
 497         if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) - 1 &&
 498             mpd_status_get_queue_version(status) == c->playlist.version + 1) {
 499                 /* the cheap route: match on the new playlist length
 500                    and its version, we can keep our local playlist
 501                    copy in sync */
 502                 c->playlist.version = mpd_status_get_queue_version(status);
 503
 504                 /* remove the song from the local playlist */
 505                 playlist_remove(&c->playlist, idx);
 506
 507                 /* remove references to the song */
 508                 if (c->song == song)
 509                         c->song = NULL;
 510         }
 511
 512         return true;
 513 }
 514
 515 /**
 516  * Fallback for mpdclient_cmd_delete_range() on MPD older than 0.16.
 517  * It emulates the "delete range" command with a list of simple
 518  * "delete" commands.
 519  */
 520 static bool
 521 mpdclient_cmd_delete_range_fallback(struct mpdclient *c,
 522                                     unsigned start, unsigned end)
 523 {
 524         struct mpd_connection *connection = mpdclient_get_connection(c);
 525         if (connection == NULL)
 526                 return false;
 527
 528         if (!mpd_command_list_begin(connection, false))
 529                 return mpdclient_handle_error(c);
 530
 531         for (; start < end; --end)
 532                 mpd_send_delete(connection, start);
 533
 534         if (!mpd_command_list_end(connection) ||
 535             !mpd_response_finish(connection))
 536                 return mpdclient_handle_error(c);
 537
 538         return true;
 539 }
 540
 541 bool
 542 mpdclient_cmd_delete_range(struct mpdclient *c, unsigned start, unsigned end)
 543 {
 544         struct mpd_connection *connection;
 545         struct mpd_status *status;
 546
 547         connection = mpdclient_get_connection(c);
 548         if (connection == NULL)
 549                 return false;
 550
 551         if (mpd_connection_cmp_server_version(connection, 0, 16, 0) < 0)
 552                 return mpdclient_cmd_delete_range_fallback(c, start, end);
 553
 554         /* MPD 0.16 supports "delete" with a range argument */
 555
 556         /* send the delete command to mpd; at the same time, get the
 557            new status (to verify the playlist id) */
 558
 559         if (!mpd_command_list_begin(connection, false) ||
 560             !mpd_send_delete_range(connection, start, end) ||
 561             !mpd_send_status(connection) ||
 562             !mpd_command_list_end(connection))
 563                 return mpdclient_handle_error(c);
 564
 565         c->events |= MPD_IDLE_PLAYLIST;
 566
 567         status = mpd_recv_status(connection);
 568         if (status != NULL) {
 569                 if (c->status != NULL)
 570                         mpd_status_free(c->status);
 571                 c->status = status;
 572         }
 573
 574         if (!mpd_response_finish(connection))
 575                 return mpdclient_handle_error(c);
 576
 577         if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) - (end - start) &&
 578             mpd_status_get_queue_version(status) == c->playlist.version + 1) {
 579                 /* the cheap route: match on the new playlist length
 580                    and its version, we can keep our local playlist
 581                    copy in sync */
 582                 c->playlist.version = mpd_status_get_queue_version(status);
 583
 584                 /* remove the song from the local playlist */
 585                 while (end > start) {
 586                         --end;
 587
 588                         /* remove references to the song */
 589                         if (c->song == playlist_get(&c->playlist, end))
 590                                 c->song = NULL;
 591
 592                         playlist_remove(&c->playlist, end);
 593                 }
 594         }
 595
 596         return true;
 597 }
 598
 599 bool
 600 mpdclient_cmd_move(struct mpdclient *c, gint old_index, gint new_index)
 601 {
 602         struct mpd_connection *connection = mpdclient_get_connection(c);
 603         const struct mpd_song *song1, *song2;
 604         struct mpd_status *status;
 605
 606         if (connection == NULL)
 607                 return false;
 608
 609         if (old_index == new_index || new_index < 0 ||
 610             (guint)new_index >= c->playlist.list->len)
 611                 return false;
 612
 613         song1 = playlist_get(&c->playlist, old_index);
 614         song2 = playlist_get(&c->playlist, new_index);
 615
 616         /* send the delete command to mpd; at the same time, get the
 617            new status (to verify the playlist id) */
 618
 619         if (!mpd_command_list_begin(connection, false) ||
 620             !mpd_send_swap_id(connection, mpd_song_get_id(song1),
 621                               mpd_song_get_id(song2)) ||
 622             !mpd_send_status(connection) ||
 623             !mpd_command_list_end(connection))
 624                 return mpdclient_handle_error(c);
 625
 626         c->events |= MPD_IDLE_PLAYLIST;
 627
 628         status = mpd_recv_status(connection);
 629         if (status != NULL) {
 630                 if (c->status != NULL)
 631                         mpd_status_free(c->status);
 632                 c->status = status;
 633         }
 634
 635         if (!mpd_response_finish(connection))
 636                 return mpdclient_handle_error(c);
 637
 638         if (mpd_status_get_queue_length(status) == playlist_length(&c->playlist) &&
 639             mpd_status_get_queue_version(status) == c->playlist.version + 1) {
 640                 /* the cheap route: match on the new playlist length
 641                    and its version, we can keep our local playlist
 642                    copy in sync */
 643                 c->playlist.version = mpd_status_get_queue_version(status);
 644
 645                 /* swap songs in the local playlist */
 646                 playlist_swap(&c->playlist, old_index, new_index);
 647         }
 648
 649         return true;
 650 }
 651
 652
 653 /****************************************************************************/
 654 /*** Playlist management functions ******************************************/
 655 /****************************************************************************/
 656
 657 /* update playlist */
 658 bool
 659 mpdclient_playlist_update(struct mpdclient *c)
 660 {
 661         struct mpd_connection *connection = mpdclient_get_connection(c);
 662         struct mpd_entity *entity;
 663
 664         if (connection == NULL)
 665                 return false;
 666
 667         playlist_clear(&c->playlist);
 668
 669         mpd_send_list_queue_meta(connection);
 670         while ((entity = mpd_recv_entity(connection))) {
 671                 if (mpd_entity_get_type(entity) == MPD_ENTITY_TYPE_SONG)
 672                         playlist_append(&c->playlist, mpd_entity_get_song(entity));
 673
 674                 mpd_entity_free(entity);
 675         }
 676
 677         c->playlist.version = mpd_status_get_queue_version(c->status);
 678         c->song = NULL;
 679
 680         return mpdclient_finish_command(c);
 681 }
 682
 683 /* update playlist (plchanges) */
 684 bool
 685 mpdclient_playlist_update_changes(struct mpdclient *c)
 686 {
 687         struct mpd_connection *connection = mpdclient_get_connection(c);
 688         struct mpd_song *song;
 689         guint length;
 690
 691         if (connection == NULL)
 692                 return false;
 693
 694         mpd_send_queue_changes_meta(connection, c->playlist.version);
 695
 696         while ((song = mpd_recv_song(connection)) != NULL) {
 697                 int pos = mpd_song_get_pos(song);
 698
 699                 if (pos >= 0 && (guint)pos < c->playlist.list->len) {
 700                         /* update song */
 701                         playlist_replace(&c->playlist, pos, song);
 702                 } else {
 703                         /* add a new song */
 704                         playlist_append(&c->playlist, song);
 705                 }
 706
 707                 mpd_song_free(song);
 708         }
 709
 710         /* remove trailing songs */
 711
 712         length = mpd_status_get_queue_length(c->status);
 713         while (length < c->playlist.list->len) {
 714                 guint pos = c->playlist.list->len - 1;
 715
 716                 /* Remove the last playlist entry */
 717                 playlist_remove(&c->playlist, pos);
 718         }
 719
 720         c->song = NULL;
 721         c->playlist.version = mpd_status_get_queue_version(c->status);
 722
 723         return mpdclient_finish_command(c);
 724 }
 725
 726
 727 /****************************************************************************/
 728 /*** Filelist functions *****************************************************/
 729 /****************************************************************************/
 730
 731 bool
 732 mpdclient_filelist_add_all(struct mpdclient *c, struct filelist *fl)
 733 {
 734         struct mpd_connection *connection = mpdclient_get_connection(c);
 735         guint i;
 736
 737         if (connection == NULL)
 738                 return false;
 739
 740         if (filelist_is_empty(fl))
 741                 return true;
 742
 743         mpd_command_list_begin(connection, false);
 744
 745         for (i = 0; i < filelist_length(fl); ++i) {
 746                 struct filelist_entry *entry = filelist_get(fl, i);
 747                 struct mpd_entity *entity  = entry->entity;
 748
 749                 if (entity != NULL &&
 750                     mpd_entity_get_type(entity) == MPD_ENTITY_TYPE_SONG) {
 751                         const struct mpd_song *song =
 752                                 mpd_entity_get_song(entity);
 753
 754                         mpd_send_add(connection, mpd_song_get_uri(song));
 755                 }
 756         }
 757
 758         mpd_command_list_end(connection);
 759         return mpdclient_finish_command(c);
 760 }
 761
 762 GList *
 763 mpdclient_get_artists(struct mpdclient *c)
 764 {
 765         struct mpd_connection *connection = mpdclient_get_connection(c);
 766         GList *list = NULL;
 767         struct mpd_pair *pair;
 768
 769         if (connection == NULL)
 770                 return NULL;
 771
 772         mpd_search_db_tags(connection, MPD_TAG_ARTIST);
 773         mpd_search_commit(connection);
 774
 775         while ((pair = mpd_recv_pair_tag(connection,
 776                                          MPD_TAG_ARTIST)) != NULL) {
 777                 list = g_list_append(list, g_strdup(pair->value));
 778                 mpd_return_pair(connection, pair);
 779         }
 780
 781         if (!mpdclient_finish_command(c))
 782                 return string_list_free(list);
 783
 784         return list;
 785 }
 786
 787 GList *
 788 mpdclient_get_albums(struct mpdclient *c, const gchar *artist_utf8)
 789 {
 790         struct mpd_connection *connection = mpdclient_get_connection(c);
 791         GList *list = NULL;
 792         struct mpd_pair *pair;
 793
 794         if (connection == NULL)
 795                 return NULL;
 796
 797         mpd_search_db_tags(connection, MPD_TAG_ALBUM);
 798         if (artist_utf8 != NULL)
 799                 mpd_search_add_tag_constraint(connection,
 800                                               MPD_OPERATOR_DEFAULT,
 801                                               MPD_TAG_ARTIST, artist_utf8);
 802         mpd_search_commit(connection);
 803
 804         while ((pair = mpd_recv_pair_tag(connection,
 805                                          MPD_TAG_ALBUM)) != NULL) {
 806                 list = g_list_append(list, g_strdup(pair->value));
 807                 mpd_return_pair(connection, pair);
 808         }
 809
 810         if (!mpdclient_finish_command(c))
 811                 return string_list_free(list);
 812
 813         return list;
 814 }