mdw@git.distorted.org.uk Git - disorder/blob - disobedience/log.c

   1 /*
   2  * This file is part of DisOrder.
   3  * Copyright (C) 2006, 2007 Richard Kettlewell
   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, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * 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, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  18  * USA
  19  */
  20 /** @file disobedience/log.c
  21  * @brief State monitoring
  22  *
  23  * Disobedience relies on the server to tell when essentially anything changes,
  24  * even if it initiated the change itself.  It uses the @c log command to
  25  * achieve this.
  26  */
  27
  28 #include "disobedience.h"
  29
  30 /* State monitoring -------------------------------------------------------- */
  31
  32 static void log_connected(void *v);
  33 static void log_completed(void *v, const char *track);
  34 static void log_failed(void *v, const char *track, const char *status);
  35 static void log_moved(void *v, const char *user);
  36 static void log_playing(void *v, const char *track, const char *user);
  37 static void log_queue(void *v, struct queue_entry *q);
  38 static void log_recent_added(void *v, struct queue_entry *q);
  39 static void log_recent_removed(void *v, const char *id);
  40 static void log_removed(void *v, const char *id, const char *user);
  41 static void log_scratched(void *v, const char *track, const char *user);
  42 static void log_state(void *v, unsigned long state);
  43 static void log_volume(void *v, int l, int r);
  44
  45 /** @brief Callbacks for server state monitoring */
  46 const disorder_eclient_log_callbacks log_callbacks = {
  47   log_connected,
  48   log_completed,
  49   log_failed,
  50   log_moved,
  51   log_playing,
  52   log_queue,
  53   log_recent_added,
  54   log_recent_removed,
  55   log_removed,
  56   log_scratched,
  57   log_state,
  58   log_volume
  59 };
  60
  61 /** @brief State monitor
  62  *
  63  * We keep a linked list of everything that is interested in state changes.
  64  */
  65 struct monitor {
  66   /** @brief Next monitor */
  67   struct monitor *next;
  68
  69   /** @brief State bits of interest */
  70   unsigned long mask;
  71
  72   /** @brief Function to call if any of @c mask change */
  73   monitor_callback *callback;
  74
  75   /** @brief User data for callback */
  76   void *u;
  77 };
  78
  79 /** @brief List of monitors */
  80 static struct monitor *monitors;
  81
  82 /** @brief Update everything */
  83 void all_update(void) {
  84   queue_update();
  85   recent_update();
  86   volume_update();
  87 }
  88
  89 /** @brief Called when the client connects
  90  *
  91  * Depending on server and network state the TCP connection to the server may
  92  * go up or down many times during the lifetime of Disobedience.  This function
  93  * is called whenever it connects.
  94  *
  95  * The intent is to use the monitor logic to achieve this in future.
  96  */
  97 static void log_connected(void attribute((unused)) *v) {
  98   /* Don't know what we might have missed while disconnected so update
  99    * everything.  We get this at startup too and this is how we do the initial
 100    * state fetch. */
 101   all_update();
 102 }
 103
 104 /** @brief Called when the current track finishes playing */
 105 static void log_completed(void attribute((unused)) *v,
 106                           const char attribute((unused)) *track) {
 107 }
 108
 109 /** @brief Called when the current track fails */
 110 static void log_failed(void attribute((unused)) *v,
 111                        const char attribute((unused)) *track,
 112                        const char attribute((unused)) *status) {
 113 }
 114
 115 /** @brief Called when some track is moved within the queue */
 116 static void log_moved(void attribute((unused)) *v,
 117                       const char attribute((unused)) *user) {
 118   queue_update();
 119 }
 120
 121 static void log_playing(void attribute((unused)) *v,
 122                         const char attribute((unused)) *track,
 123                         const char attribute((unused)) *user) {
 124 }
 125
 126 /** @brief Called when a track is added to the queue */
 127 static void log_queue(void attribute((unused)) *v,
 128                       struct queue_entry attribute((unused)) *q) {
 129   queue_update();
 130 }
 131
 132 /** @brief Called when a track is added to the recently-played list */
 133 static void log_recent_added(void attribute((unused)) *v,
 134                              struct queue_entry attribute((unused)) *q) {
 135   recent_update();
 136 }
 137
 138 /** @brief Called when a track is removed from the recently-played list
 139  *
 140  * We do nothing here - log_recent_added() suffices.
 141  */
 142 static void log_recent_removed(void attribute((unused)) *v,
 143                                const char attribute((unused)) *id) {
 144   /* nothing - log_recent_added() will trigger the relevant update */
 145 }
 146
 147 /** @brief Called when a track is removed from the queue */
 148 static void log_removed(void attribute((unused)) *v,
 149                         const char attribute((unused)) *id,
 150                         const char attribute((unused)) *user) {
 151   queue_update();
 152 }
 153
 154 /** @brief Called when the current track is scratched */
 155 static void log_scratched(void attribute((unused)) *v,
 156                           const char attribute((unused)) *track,
 157                           const char attribute((unused)) *user) {
 158 }
 159
 160 /** @brief Called when a state change occurs */
 161 static void log_state(void attribute((unused)) *v,
 162                       unsigned long state) {
 163   const struct monitor *m;
 164   unsigned long changes = state ^ last_state;
 165   static int first = 1;
 166
 167   if(first) {
 168     changes = -1UL;
 169     first = 0;
 170   }
 171   D(("log_state old=%s new=%s changed=%s",
 172      disorder_eclient_interpret_state(last_state),
 173      disorder_eclient_interpret_state(state),
 174      disorder_eclient_interpret_state(changes)));
 175   last_state = state;
 176   /* Tell anything that cares about the state change */
 177   for(m = monitors; m; m = m->next) {
 178     if(changes & m->mask)
 179       m->callback(m->u);
 180   }
 181 }
 182
 183 /** @brief Called when volume changes */
 184 static void log_volume(void attribute((unused)) *v,
 185                        int l, int r) {
 186   if(volume_l != l || volume_r != r) {
 187     volume_l = l;
 188     volume_r = r;
 189     volume_update();
 190   }
 191 }
 192
 193 /** @brief Add a monitor to the list
 194  * @param callback Function to call
 195  * @param u User data to pass to @p callback
 196  * @param mask Mask of flags that @p callback cares about
 197  *
 198  * Pass @p mask as -1UL to match all flags.
 199  */
 200 void register_monitor(monitor_callback *callback,
 201                       void *u,
 202                       unsigned long mask) {
 203   struct monitor *m = xmalloc(sizeof *m);
 204
 205   m->next = monitors;
 206   m->mask = mask;
 207   m->callback = callback;
 208   m->u = u;
 209   monitors = m;
 210 }
 211
 212 /*
 213 Local Variables:
 214 c-basic-offset:2
 215 comment-column:40
 216 fill-column:79
 217 indent-tabs-mode:nil
 218 End:
 219 */