metadata_hub.c

   1 /*
   2  * Metadata hub and access methods.
   3  * Basically, if you need to store metadata
   4  * (e.g. for use with the dbus interfaces),
   5  * then you need a metadata hub,
   6  * where everything is stored
   7  * This file is part of Shairport Sync.
   8  * Copyright (c) Mike Brady 2017--2022
   9  * All rights reserved.
  10  *
  11  * Permission is hereby granted, free of charge, to any person
  12  * obtaining a copy of this software and associated documentation
  13  * files (the "Software"), to deal in the Software without
  14  * restriction, including without limitation the rights to use,
  15  * copy, modify, merge, publish, distribute, sublicense, and/or
  16  * sell copies of the Software, and to permit persons to whom the
  17  * Software is furnished to do so, subject to the following conditions:
  18  *
  19  * The above copyright notice and this permission notice shall be
  20  * included in all copies or substantial portions of the Software.
  21  *
  22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  23  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
  24  * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  25  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  26  * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  27  * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  28  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  29  * OTHER DEALINGS IN THE SOFTWARE.
  30  */
  31
  32 #include <stdlib.h>
  33 #include <string.h>
  34
  35 #include <dirent.h>
  36 #include <errno.h>
  37 #include <fcntl.h>
  38 #include <inttypes.h>
  39 #include <sys/stat.h>
  40 #include <sys/types.h>
  41 #include <unistd.h>
  42
  43 #include "config.h"
  44
  45 #include "common.h"
  46 #include "dacp.h"
  47 #include "metadata_hub.h"
  48
  49 #ifdef CONFIG_MBEDTLS
  50 #include <mbedtls/md5.h>
  51 #include <mbedtls/version.h>
  52 #endif
  53
  54 #ifdef CONFIG_POLARSSL
  55 #include <polarssl/md5.h>
  56 #endif
  57
  58 #ifdef CONFIG_OPENSSL
  59 #include <openssl/evp.h>
  60 #endif
  61
  62 struct metadata_bundle metadata_store;
  63
  64 int metadata_hub_initialised = 0;
  65
  66 pthread_rwlock_t metadata_hub_re_lock = PTHREAD_RWLOCK_INITIALIZER;
  67
  68 int string_update(char **str, int *flag, char *s) {
  69   if (s)
  70     return string_update_with_size(str, flag, s, strlen(s));
  71   else
  72     return string_update_with_size(str, flag, NULL, 0);
  73 }
  74
  75 void metadata_hub_init(void) {
  76   // debug(1, "Metadata bundle initialisation.");
  77   memset(&metadata_store, 0, sizeof(metadata_store));
  78   metadata_hub_initialised = 1;
  79 }
  80
  81 void metadata_hub_stop(void) {}
  82
  83 void add_metadata_watcher(metadata_watcher fn, void *userdata) {
  84   int i;
  85   for (i = 0; i < number_of_watchers; i++) {
  86     if (metadata_store.watchers[i] == NULL) {
  87       metadata_store.watchers[i] = fn;
  88       metadata_store.watchers_data[i] = userdata;
  89       // debug(1, "Added a metadata watcher into slot %d", i);
  90       break;
  91     }
  92   }
  93 }
  94
  95 void run_metadata_watchers(void) {
  96   int i;
  97   for (i = 0; i < number_of_watchers; i++) {
  98     if (metadata_store.watchers[i]) {
  99       metadata_store.watchers[i](&metadata_store, metadata_store.watchers_data[i]);
 100     }
 101   }
 102   // turn off changed flags
 103   metadata_store.cover_art_pathname_changed = 0;
 104   metadata_store.client_ip_changed = 0;
 105   metadata_store.client_name_changed = 0;
 106   metadata_store.server_ip_changed = 0;
 107   metadata_store.progress_string_changed = 0;
 108   metadata_store.item_id_changed = 0;
 109   metadata_store.item_composite_id_changed = 0;
 110   metadata_store.artist_name_changed = 0;
 111   metadata_store.album_artist_name_changed = 0;
 112   metadata_store.album_name_changed = 0;
 113   metadata_store.song_data_kind_changed = 0;
 114   metadata_store.track_name_changed = 0;
 115   metadata_store.genre_changed = 0;
 116   metadata_store.comment_changed = 0;
 117   metadata_store.composer_changed = 0;
 118   metadata_store.file_kind_changed = 0;
 119   metadata_store.song_description_changed = 0;
 120   metadata_store.song_album_artist_changed = 0;
 121   metadata_store.sort_artist_changed = 0;
 122   metadata_store.sort_album_changed = 0;
 123   metadata_store.sort_composer_changed = 0;
 124   metadata_store.songtime_in_milliseconds_changed = 0;
 125 }
 126
 127 void metadata_hub_unlock_hub_mutex_cleanup(__attribute__((unused)) void *arg) {
 128   debug(1, "metadata_hub_unlock_hub_mutex_cleanup called.");
 129   metadata_hub_modify_epilog(0);
 130 }
 131
 132 char *last_metadata_hub_modify_prolog_file = NULL;
 133 int last_metadata_hub_modify_prolog_line;
 134 int metadata_hub_re_lock_access_is_delayed;
 135
 136 void _metadata_hub_modify_prolog(const char *filename, const int linenumber) {
 137   // always run this before changing an entry or a sequence of entries in the metadata_hub
 138   // debug(1, "locking metadata hub for writing");
 139   if (pthread_rwlock_trywrlock(&metadata_hub_re_lock) != 0) {
 140     if (last_metadata_hub_modify_prolog_file)
 141       debug(2, "Metadata_hub write lock at \"%s:%d\" is already taken at \"%s:%d\" -- must wait.",
 142             filename, linenumber, last_metadata_hub_modify_prolog_file,
 143             last_metadata_hub_modify_prolog_line);
 144     else
 145       debug(2, "Metadata_hub write lock is already taken by unknown -- must wait.");
 146     metadata_hub_re_lock_access_is_delayed = 0;
 147     pthread_rwlock_wrlock(&metadata_hub_re_lock);
 148     debug(2, "Okay -- acquired the metadata_hub write lock at \"%s:%d\".", filename, linenumber);
 149   } else {
 150     if (last_metadata_hub_modify_prolog_file) {
 151       free(last_metadata_hub_modify_prolog_file);
 152     }
 153     last_metadata_hub_modify_prolog_file = strdup(filename);
 154     last_metadata_hub_modify_prolog_line = linenumber;
 155     // debug(3, "Metadata_hub write lock acquired.");
 156   }
 157   metadata_hub_re_lock_access_is_delayed = 0;
 158 }
 159
 160 void _metadata_hub_modify_epilog(int modified, const char *filename, const int linenumber) {
 161   metadata_store.dacp_server_has_been_active =
 162       metadata_store.dacp_server_active; // set the scanner_has_been_active now.
 163   if (modified) {
 164     run_metadata_watchers();
 165   }
 166   if (metadata_hub_re_lock_access_is_delayed) {
 167     if (last_metadata_hub_modify_prolog_file) {
 168       debug(1, "Metadata_hub write lock taken at \"%s:%d\" is freed at \"%s:%d\".",
 169             last_metadata_hub_modify_prolog_file, last_metadata_hub_modify_prolog_line, filename,
 170             linenumber);
 171       free(last_metadata_hub_modify_prolog_file);
 172       last_metadata_hub_modify_prolog_file = NULL;
 173     } else {
 174       debug(1, "Metadata_hub write lock taken at an unknown place is freed at \"%s:%d\".", filename,
 175             linenumber);
 176     }
 177   }
 178   pthread_rwlock_unlock(&metadata_hub_re_lock);
 179   // debug(3, "Metadata_hub write lock unlocked.");
 180 }
 181
 182 /*
 183 void _metadata_hub_read_prolog(const char *filename, const int linenumber) {
 184   // always run this before reading an entry or a sequence of entries in the metadata_hub
 185   // debug(1, "locking metadata hub for reading");
 186   if (pthread_rwlock_tryrdlock(&metadata_hub_re_lock) != 0) {
 187     debug(1, "Metadata_hub read lock is already taken -- must wait.");
 188     pthread_rwlock_rdlock(&metadata_hub_re_lock);
 189     debug(1, "Okay -- acquired the metadata_hub read lock.");
 190   }
 191 }
 192
 193 void _metadata_hub_read_epilog(const char *filename, const int linenumber) {
 194   // always run this after reading an entry or a sequence of entries in the metadata_hub
 195   // debug(1, "unlocking metadata hub for reading");
 196   pthread_rwlock_unlock(&metadata_hub_re_lock);
 197 }
 198 */
 199 char *metadata_write_image_file(const char *buf, int len) {
 200
 201   // warning -- this removes all files from the directory apart from this one, if it exists
 202   // it will return a path to the image file allocated with malloc.
 203   // free it if you don't need it.
 204
 205   char *path = NULL;                                 // this will be what is returned
 206   if (strcmp(config.cover_art_cache_dir, "") != 0) { // an empty string means do not write the file
 207
 208     uint8_t img_md5[16];
 209     // uint8_t ap_md5[16];
 210
 211 #ifdef CONFIG_OPENSSL
 212     EVP_MD_CTX *ctx;
 213     unsigned int img_md5_len = EVP_MD_size(EVP_md5());
 214
 215     ctx = EVP_MD_CTX_new();
 216     EVP_DigestInit_ex(ctx, EVP_md5(), NULL);
 217     EVP_DigestUpdate(ctx, buf, len);
 218     EVP_DigestFinal_ex(ctx, img_md5, &img_md5_len);
 219     EVP_MD_CTX_free(ctx);
 220 #endif
 221
 222 #ifdef CONFIG_MBEDTLS
 223 #if MBEDTLS_VERSION_MINOR >= 7
 224     mbedtls_md5_context tctx;
 225     mbedtls_md5_starts_ret(&tctx);
 226     mbedtls_md5_update_ret(&tctx, (const unsigned char *)buf, len);
 227     mbedtls_md5_finish_ret(&tctx, img_md5);
 228 #else
 229     mbedtls_md5_context tctx;
 230     mbedtls_md5_starts(&tctx);
 231     mbedtls_md5_update(&tctx, (const unsigned char *)buf, len);
 232     mbedtls_md5_finish(&tctx, img_md5);
 233 #endif
 234 #endif
 235
 236 #ifdef CONFIG_POLARSSL
 237     md5_context tctx;
 238     md5_starts(&tctx);
 239     md5_update(&tctx, (const unsigned char *)buf, len);
 240     md5_finish(&tctx, img_md5);
 241 #endif
 242
 243     char img_md5_str[33];
 244     memset(img_md5_str, 0, sizeof(img_md5_str));
 245     char *ext;
 246     char png[] = "png";
 247     char jpg[] = "jpg";
 248     int i;
 249     for (i = 0; i < 16; i++)
 250       snprintf(&img_md5_str[i * 2], 3, "%02x", (uint8_t)img_md5[i]);
 251     // see if the file is a jpeg or a png
 252     if (strncmp(buf, "\xFF\xD8\xFF", 3) == 0)
 253       ext = jpg;
 254     else if (strncmp(buf, "\x89\x50\x4E\x47\x0D\x0A\x1A\x0A", 8) == 0)
 255       ext = png;
 256     else {
 257       debug(1, "Unidentified image type of cover art -- jpg extension used.");
 258       ext = jpg;
 259     }
 260     mode_t oldumask = umask(000);
 261     int result = mkpath(config.cover_art_cache_dir, 0777);
 262     umask(oldumask);
 263     if ((result == 0) || (result == -EEXIST)) {
 264       // see if the file exists by opening it.
 265       // if it exists, we're done
 266       char *prefix = "cover-";
 267
 268       size_t pl = strlen(config.cover_art_cache_dir) + 1 + strlen(prefix) + strlen(img_md5_str) +
 269                   1 + strlen(ext);
 270
 271       path = malloc(pl + 1);
 272       snprintf(path, pl + 1, "%s/%s%s.%s", config.cover_art_cache_dir, prefix, img_md5_str, ext);
 273       int cover_fd = open(path, O_WRONLY | O_CREAT | O_EXCL, S_IRWXU | S_IRGRP | S_IROTH);
 274       if (cover_fd > 0) {
 275         // write the contents
 276         if (write(cover_fd, buf, len) < len) {
 277           warn("Writing cover art file \"%s\" failed!", path);
 278           free(path);
 279           path = NULL;
 280         }
 281         close(cover_fd);
 282
 283         // now delete all other files, if requested
 284         if (config.retain_coverart == 0) {
 285           DIR *d;
 286           struct dirent *dir;
 287           d = opendir(config.cover_art_cache_dir);
 288           if (d) {
 289             int fnl = strlen(prefix) + strlen(img_md5_str) + 1 + strlen(ext) + 1;
 290
 291             char *full_filename = malloc(fnl);
 292             if (full_filename == NULL)
 293               die("Can't allocate memory at metadata_write_image_file.");
 294             memset(full_filename, 0, fnl);
 295             snprintf(full_filename, fnl, "%s%s.%s", prefix, img_md5_str, ext);
 296             int dir_fd = open(config.cover_art_cache_dir, O_DIRECTORY);
 297             if (dir_fd > 0) {
 298               while ((dir = readdir(d)) != NULL) {
 299                 if (dir->d_type == DT_REG) {
 300                   if (strcmp(full_filename, dir->d_name) != 0) {
 301                     if (unlinkat(dir_fd, dir->d_name, 0) != 0) {
 302                       debug(1, "Error %d deleting cover art file \"%s\".", errno, dir->d_name);
 303                     }
 304                   }
 305                 }
 306               }
 307               if (close(dir_fd) < 0)
 308                 debug(1, "Error %d closing directory \"%s\"", errno, config.cover_art_cache_dir);
 309             } else {
 310               debug(1, "Can't open the directory \"%s\" for deletion -- error %d.",
 311                     config.cover_art_cache_dir, errno);
 312             }
 313             free(full_filename);
 314             closedir(d);
 315           }
 316         }
 317       } else {
 318         //      if (errno == EEXIST)
 319         //        debug(1, "Cover art file \"%s\" already exists!", path);
 320         //      else {
 321         if (errno != EEXIST) {
 322           warn("Could not open file \"%s\" for writing cover art", path);
 323           free(path);
 324           path = NULL;
 325         }
 326       }
 327     } else {
 328       debug(1, "Couldn't access or create the cover art cache directory \"%s\".",
 329             config.cover_art_cache_dir);
 330     }
 331   }
 332   return path;
 333 }
 334
 335 int metadata_packet_item_changed = 0; // set if any parsed part of a metadata stream changes
 336
 337 void metadata_hub_process_metadata(uint32_t type, uint32_t code, char *data, uint32_t length) {
 338   // metadata coming in from the audio source or from Shairport Sync itself passes through here
 339   // this has more information about tags, which might be relevant:
 340   // https://code.google.com/p/ytrack/wiki/DMAP
 341
 342   // Some metadata items are contained in one metadata packet.
 343   // The start of the metadata packet is signalled by an 'ssnc' 'mdst' item and
 344   // the end of it by an 'ssnc 'mden' item.
 345   // We don't set "changed" for them individually; instead we set it when the  'mden' token
 346   // comes in if the metadata_packet_item_changed item is set by parsed items
 347   // within the packet.
 348
 349   int changed = 0;
 350   metadata_hub_modify_prolog();
 351   pthread_cleanup_push(metadata_hub_unlock_hub_mutex_cleanup, NULL);
 352
 353   char *cs;
 354   if (type == 'core') {
 355     switch (code) {
 356     case 'asdk': {
 357       // get the one-byte number as an unsigned number
 358       int song_data_kind = data[0];           // one byte
 359       song_data_kind = song_data_kind & 0xFF; // unsigned
 360       debug(2, "MH Song Data Kind seen: \"%d\" of length %u.", song_data_kind, length);
 361       if ((song_data_kind != metadata_store.song_data_kind) ||
 362           (metadata_store.song_data_kind_is_valid == 0)) {
 363         metadata_store.song_data_kind = song_data_kind;
 364         metadata_store.song_data_kind_changed = 1;
 365         metadata_store.song_data_kind_is_valid = 1;
 366         debug(2, "MH Song Data Kind set to: \"%d\"", metadata_store.song_data_kind);
 367         metadata_packet_item_changed = 1;
 368       }
 369     } break;
 370     case 'mper': {
 371       // get the 64-bit number as a uint64_t by reading two uint32_t s and combining them
 372       uint64_t vl = ntohl(*(uint32_t *)data); // get the high order 32 bits
 373       vl = vl << 32;                          // shift them into the correct location
 374       uint64_t ul = ntohl(*(uint32_t *)(data + sizeof(uint32_t))); // and the low order 32 bits
 375       vl = vl + ul;
 376       debug(2, "MH Item ID seen: \"%" PRIx64 "\" of length %u.", vl, length);
 377       if ((vl != metadata_store.item_id) || (metadata_store.item_id_is_valid == 0)) {
 378         metadata_store.item_id = vl;
 379         metadata_store.item_id_changed = 1;
 380         metadata_store.item_id_is_valid = 1;
 381         debug(2, "MH Item ID set to: \"%" PRIx64 "\"", metadata_store.item_id);
 382         metadata_packet_item_changed = 1;
 383       }
 384     } break;
 385     case 'astm': {
 386       uint32_t ui = ntohl(*(uint32_t *)data);
 387       debug(2, "MH Song Time seen: \"%u\" of length %u.", ui, length);
 388       if ((ui != metadata_store.songtime_in_milliseconds) ||
 389           (metadata_store.songtime_in_milliseconds_is_valid == 0)) {
 390         metadata_store.songtime_in_milliseconds = ui;
 391         metadata_store.songtime_in_milliseconds_changed = 1;
 392         metadata_store.songtime_in_milliseconds_is_valid = 1;
 393         debug(2, "MH Song Time set to: \"%u\"", metadata_store.songtime_in_milliseconds);
 394         metadata_packet_item_changed = 1;
 395       }
 396     } break;
 397     case 'asal':
 398       cs = strndup(data, length);
 399       if (string_update(&metadata_store.album_name, &metadata_store.album_name_changed, cs)) {
 400         debug(2, "MH Album name set to: \"%s\"", metadata_store.album_name);
 401         metadata_packet_item_changed = 1;
 402       }
 403       free(cs);
 404       break;
 405     case 'asar':
 406       cs = strndup(data, length);
 407       if (string_update(&metadata_store.artist_name, &metadata_store.artist_name_changed, cs)) {
 408         debug(2, "MH Artist name set to: \"%s\"", metadata_store.artist_name);
 409         metadata_packet_item_changed = 1;
 410       }
 411       free(cs);
 412       break;
 413     case 'assl':
 414       cs = strndup(data, length);
 415       if (string_update(&metadata_store.album_artist_name,
 416                         &metadata_store.album_artist_name_changed, cs)) {
 417         debug(2, "MH Album Artist name set to: \"%s\"", metadata_store.album_artist_name);
 418         metadata_packet_item_changed = 1;
 419       }
 420       free(cs);
 421       break;
 422     case 'ascm':
 423       cs = strndup(data, length);
 424       if (string_update(&metadata_store.comment, &metadata_store.comment_changed, cs)) {
 425         debug(2, "MH Comment set to: \"%s\"", metadata_store.comment);
 426         metadata_packet_item_changed = 1;
 427       }
 428       free(cs);
 429       break;
 430     case 'asgn':
 431       cs = strndup(data, length);
 432       if (string_update(&metadata_store.genre, &metadata_store.genre_changed, cs)) {
 433         debug(2, "MH Genre set to: \"%s\"", metadata_store.genre);
 434         metadata_packet_item_changed = 1;
 435       }
 436       free(cs);
 437       break;
 438     case 'minm':
 439       cs = strndup(data, length);
 440       if (string_update(&metadata_store.track_name, &metadata_store.track_name_changed, cs)) {
 441         debug(2, "MH Track Name set to: \"%s\"", metadata_store.track_name);
 442         metadata_packet_item_changed = 1;
 443       }
 444       free(cs);
 445       break;
 446     case 'ascp':
 447       cs = strndup(data, length);
 448       if (string_update(&metadata_store.composer, &metadata_store.composer_changed, cs)) {
 449         debug(2, "MH Composer set to: \"%s\"", metadata_store.composer);
 450         metadata_packet_item_changed = 1;
 451       }
 452       free(cs);
 453       break;
 454     case 'asdt':
 455       cs = strndup(data, length);
 456       if (string_update(&metadata_store.song_description, &metadata_store.song_description_changed,
 457                         cs)) {
 458         debug(2, "MH Song Description set to: \"%s\"", metadata_store.song_description);
 459       }
 460       free(cs);
 461       break;
 462     case 'asaa':
 463       cs = strndup(data, length);
 464       if (string_update(&metadata_store.song_album_artist,
 465                         &metadata_store.song_album_artist_changed, cs)) {
 466         debug(2, "MH Song Album Artist set to: \"%s\"", metadata_store.song_album_artist);
 467         metadata_packet_item_changed = 1;
 468       }
 469       free(cs);
 470       break;
 471     case 'assn':
 472       cs = strndup(data, length);
 473       if (string_update(&metadata_store.sort_name, &metadata_store.sort_name_changed, cs)) {
 474         debug(2, "MH Sort Name set to: \"%s\"", metadata_store.sort_name);
 475         metadata_packet_item_changed = 1;
 476       }
 477       free(cs);
 478       break;
 479     case 'assa':
 480       cs = strndup(data, length);
 481       if (string_update(&metadata_store.sort_artist, &metadata_store.sort_artist_changed, cs)) {
 482         debug(2, "MH Sort Artist set to: \"%s\"", metadata_store.sort_artist);
 483         metadata_packet_item_changed = 1;
 484       }
 485       free(cs);
 486       break;
 487     case 'assu':
 488       cs = strndup(data, length);
 489       if (string_update(&metadata_store.sort_album, &metadata_store.sort_album_changed, cs)) {
 490         debug(2, "MH Sort Album set to: \"%s\"", metadata_store.sort_album);
 491         metadata_packet_item_changed = 1;
 492       }
 493       free(cs);
 494       break;
 495     case 'assc':
 496       cs = strndup(data, length);
 497       if (string_update(&metadata_store.sort_composer, &metadata_store.sort_composer_changed, cs)) {
 498         debug(2, "MH Sort Composer set to: \"%s\"", metadata_store.sort_composer);
 499         metadata_packet_item_changed = 1;
 500       }
 501       free(cs);
 502     default:
 503       /*
 504           {
 505             char typestring[5];
 506             *(uint32_t *)typestring = htonl(type);
 507             typestring[4] = 0;
 508             char codestring[5];
 509             *(uint32_t *)codestring = htonl(code);
 510             codestring[4] = 0;
 511             char *payload;
 512             if (length < 2048)
 513               payload = strndup(data, length);
 514             else
 515               payload = NULL;
 516             debug(1, "MH \"%s\" \"%s\" (%d bytes): \"%s\".", typestring, codestring, length,
 517          payload);
 518             if (payload)
 519               free(payload);
 520           }
 521       */
 522       break;
 523     }
 524   } else if (type == 'ssnc') {
 525     switch (code) {
 526     // ignore the following
 527     case 'pcst':
 528     case 'pcen':
 529       break;
 530     case 'mdst':
 531       debug(2, "MH Metadata stream processing start.");
 532       metadata_packet_item_changed = 0;
 533       break;
 534     case 'mden':
 535       if (metadata_packet_item_changed != 0)
 536         debug(2, "MH Metadata stream processing end with changes.");
 537       else
 538         debug(2, "MH Metadata stream processing end without changes.");
 539       changed = metadata_packet_item_changed;
 540       break;
 541     case 'PICT':
 542       debug(2, "MH Picture received, length %u bytes.", length);
 543
 544       char uri[2048];
 545       if ((length > 16) &&
 546           (strcmp(config.cover_art_cache_dir, "") != 0)) { // if it's okay to write the file
 547                                                            // make this uncancellable
 548         int oldState;
 549         pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &oldState); // make this un-cancellable
 550         char *pathname = metadata_write_image_file(data, length);
 551         snprintf(uri, sizeof(uri), "file://%s", pathname);
 552         free(pathname);
 553         pthread_setcancelstate(oldState, NULL);
 554
 555       } else {
 556         uri[0] = '\0';
 557       }
 558       if (string_update(&metadata_store.cover_art_pathname,
 559                         &metadata_store.cover_art_pathname_changed,
 560                         uri)) // if the picture's file path is different from the stored one...
 561         changed = 1;
 562       else
 563         changed = 0;
 564       //      pthread_cleanup_pop(0); // don't remove the lock -- it'll have been done
 565       break;
 566     case 'clip':
 567       cs = strndup(data, length);
 568       if (string_update(&metadata_store.client_ip, &metadata_store.client_ip_changed, cs)) {
 569         changed = 1;
 570         debug(2, "MH Client IP set to: \"%s\"", metadata_store.client_ip);
 571       }
 572       free(cs);
 573       break;
 574     case 'snam':
 575       cs = strndup(data, length);
 576       if (string_update(&metadata_store.client_name, &metadata_store.client_name_changed, cs)) {
 577         changed = 1;
 578         debug(2, "MH Client Name set to: \"%s\"", metadata_store.client_name);
 579       }
 580       free(cs);
 581       break;
 582     case 'prgr':
 583       cs = strndup(data, length);
 584       if (string_update(&metadata_store.progress_string, &metadata_store.progress_string_changed,
 585                         cs)) {
 586         changed = 1;
 587         debug(2, "MH Progress String set to: \"%s\"", metadata_store.progress_string);
 588       }
 589       free(cs);
 590       break;
 591     case 'phbt':
 592       cs = strndup(data, length);
 593       if (string_update(&metadata_store.frame_position_string,
 594                         &metadata_store.frame_position_string_changed, cs)) {
 595         changed = 1;
 596         debug(2, "MH Frame Position String set to: \"%s\"", metadata_store.frame_position_string);
 597       }
 598       free(cs);
 599       break;
 600     case 'phb0':
 601       cs = strndup(data, length);
 602       if (string_update(&metadata_store.first_frame_position_string,
 603                         &metadata_store.first_frame_position_string_changed, cs)) {
 604         changed = 1;
 605         debug(2, "MH First Frame Position String set to: \"%s\"",
 606               metadata_store.first_frame_position_string);
 607       }
 608       free(cs);
 609       break;
 610     case 'styp':
 611       cs = strndup(data, length);
 612       if (string_update(&metadata_store.stream_type, &metadata_store.stream_type_changed, cs)) {
 613         changed = 1;
 614         debug(2, "MH Stream Type set to: \"%s\"", metadata_store.stream_type);
 615       }
 616       free(cs);
 617       break;
 618     case 'svip':
 619       cs = strndup(data, length);
 620       if (string_update(&metadata_store.server_ip, &metadata_store.server_ip_changed, cs)) {
 621         changed = 1;
 622         debug(2, "MH Server IP set to: \"%s\"", metadata_store.server_ip);
 623       }
 624       free(cs);
 625       break;
 626     case 'abeg':
 627       changed = (metadata_store.active_state != AM_ACTIVE);
 628       metadata_store.active_state = AM_ACTIVE;
 629       break;
 630     case 'aend':
 631       changed = (metadata_store.active_state != AM_INACTIVE);
 632       metadata_store.active_state = AM_INACTIVE;
 633       break;
 634     case 'pres':
 635     case 'pbeg':
 636       changed = ((metadata_store.player_state != PS_PLAYING) ||
 637                  (metadata_store.player_thread_active == 0));
 638       metadata_store.player_state = PS_PLAYING;
 639       metadata_store.player_thread_active = 1;
 640       break;
 641     case 'pend':
 642       changed = ((metadata_store.player_state != PS_STOPPED) ||
 643                  (metadata_store.player_thread_active == 1));
 644       metadata_store.player_state = PS_STOPPED;
 645       metadata_store.player_thread_active = 0;
 646       break;
 647     case 'paus':
 648       changed = (metadata_store.player_state != PS_PAUSED);
 649       metadata_store.player_state = PS_PAUSED;
 650       break;
 651       /*
 652       // not using this anymore.
 653           case 'pffr': // this is sent when the first frame has been received
 654           case 'prsm':
 655             changed = (metadata_store.player_state != PS_PLAYING);
 656             metadata_store.player_state = PS_PLAYING;
 657             break;
 658       */
 659     case 'pvol': {
 660       // Note: it's assumed that the config.airplay volume has already been correctly set.
 661       // int32_t actual_volume;
 662       // int gv = dacp_get_volume(&actual_volume);
 663       // metadata_hub_modify_prolog();
 664       // if ((gv == 200) && (metadata_store.speaker_volume != actual_volume)) {
 665       //  metadata_store.speaker_volume = actual_volume;
 666       //  changed = 1;
 667       //}
 668       if (metadata_store.airplay_volume != config.airplay_volume) {
 669         metadata_store.airplay_volume = config.airplay_volume;
 670         changed = 1;
 671       }
 672     } break;
 673
 674     default: {
 675       char typestring[5];
 676       uint32_t tm = htonl(type);
 677       memcpy(typestring, &tm, sizeof(uint32_t));
 678       typestring[4] = 0;
 679       char codestring[5];
 680       uint32_t cm = htonl(code);
 681       memcpy(codestring, &cm, sizeof(uint32_t));
 682       codestring[4] = 0;
 683       char *payload;
 684       if (length < 2048)
 685         payload = strndup(data, length);
 686       else
 687         payload = NULL;
 688       // debug(1, "MH \"%s\" \"%s\" (%d bytes): \"%s\".", typestring, codestring, length, payload);
 689       if (payload)
 690         free(payload);
 691     }
 692     }
 693   }
 694   pthread_cleanup_pop(0); // don't remove the lock
 695   metadata_hub_modify_epilog(changed);
 696 }