| 1 | /* |
| 2 | * This file is part of DisOrder. |
| 3 | * Copyright (C) 2004-2008 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 3 of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
| 17 | */ |
| 18 | /** @file server/queue-ops.c |
| 19 | * @brief Track queues (server-specific code) |
| 20 | */ |
| 21 | #include "disorder-server.h" |
| 22 | |
| 23 | static int find_in_list(struct queue_entry *needle, |
| 24 | int nqs, struct queue_entry **qs) { |
| 25 | int n; |
| 26 | |
| 27 | for(n = 0; n < nqs; ++n) |
| 28 | if(qs[n] == needle) |
| 29 | return 1; |
| 30 | return 0; |
| 31 | } |
| 32 | |
| 33 | static int id_in_use(const char *id) { |
| 34 | struct queue_entry *q; |
| 35 | |
| 36 | for(q = qhead.next; q != &qhead; q = q->next) |
| 37 | if(!strcmp(id, q->id)) |
| 38 | return 1; |
| 39 | return 0; |
| 40 | } |
| 41 | |
| 42 | static void queue_id(struct queue_entry *q) { |
| 43 | const char *id; |
| 44 | |
| 45 | id = random_id(); |
| 46 | while(id_in_use(id)) |
| 47 | id = random_id(); |
| 48 | q->id = id; |
| 49 | } |
| 50 | |
| 51 | /** @brief Add a track to the queue |
| 52 | * @param track Track to add |
| 53 | * @param submitter Who added it, or NULL |
| 54 | * @param where Where to add it |
| 55 | * @param target ID to add after for @ref WHERE_AFTER |
| 56 | * @param origin Track origin |
| 57 | * @return New queue entry or NULL |
| 58 | * |
| 59 | * The queue is NOT saved to disk. |
| 60 | * |
| 61 | * NULL can only be returned if @ref WHERE_AFTER is used with an invalid |
| 62 | * queue ID. |
| 63 | */ |
| 64 | struct queue_entry *queue_add(const char *track, const char *submitter, |
| 65 | int where, const char *target, |
| 66 | enum track_origin origin) { |
| 67 | struct queue_entry *q, *beforeme, *afterme; |
| 68 | |
| 69 | q = xmalloc(sizeof *q); |
| 70 | q->track = xstrdup(track); |
| 71 | q->submitter = submitter ? xstrdup(submitter) : 0; |
| 72 | q->state = playing_unplayed; |
| 73 | q->origin = origin; |
| 74 | q->pid = -1; |
| 75 | queue_id(q); |
| 76 | xtime(&q->when); |
| 77 | switch(where) { |
| 78 | case WHERE_START: |
| 79 | queue_insert_entry(&qhead, q); |
| 80 | break; |
| 81 | case WHERE_END: |
| 82 | queue_insert_entry(qhead.prev, q); |
| 83 | break; |
| 84 | case WHERE_BEFORE_RANDOM: |
| 85 | /* We want to find the point in the queue before the block of random tracks |
| 86 | * at the end. */ |
| 87 | beforeme = &qhead; |
| 88 | while(beforeme->prev != &qhead |
| 89 | && beforeme->prev->origin == origin_random) |
| 90 | beforeme = beforeme->prev; |
| 91 | queue_insert_entry(beforeme->prev, q); |
| 92 | break; |
| 93 | case WHERE_AFTER: |
| 94 | if(!*target) |
| 95 | /* Insert at start of queue */ |
| 96 | afterme = &qhead; |
| 97 | else { |
| 98 | /* Insert after a specific track */ |
| 99 | afterme = qhead.next; |
| 100 | while(afterme != &qhead && strcmp(afterme->id, target)) |
| 101 | afterme = afterme->next; |
| 102 | if(afterme == &qhead) |
| 103 | return NULL; |
| 104 | } |
| 105 | queue_insert_entry(afterme, q); |
| 106 | break; |
| 107 | case WHERE_NOWHERE: |
| 108 | return q; |
| 109 | } |
| 110 | /* submitter will be a null pointer for a scratch */ |
| 111 | if(submitter) |
| 112 | notify_queue(track, submitter); |
| 113 | eventlog_raw("queue", queue_marshall(q), (const char *)0); |
| 114 | return q; |
| 115 | } |
| 116 | |
| 117 | int queue_move(struct queue_entry *q, int delta, const char *who) { |
| 118 | int moved = 0; |
| 119 | char buffer[20]; |
| 120 | |
| 121 | /* not the most efficient approach but hopefuly relatively comprehensible: |
| 122 | * the idea is that for each step we determine which nodes are affected, and |
| 123 | * fill in all the links starting at the 'prev' end and moving towards the |
| 124 | * 'next' end. */ |
| 125 | |
| 126 | while(delta > 0 && q->prev != &qhead) { |
| 127 | struct queue_entry *n, *p, *pp; |
| 128 | |
| 129 | n = q->next; |
| 130 | p = q->prev; |
| 131 | pp = p->prev; |
| 132 | pp->next = q; |
| 133 | q->prev = pp; |
| 134 | q->next = p; |
| 135 | p->prev = q; |
| 136 | p->next = n; |
| 137 | n->prev = p; |
| 138 | --delta; |
| 139 | ++moved; |
| 140 | } |
| 141 | |
| 142 | while(delta < 0 && q->next != &qhead) { |
| 143 | struct queue_entry *n, *p, *nn; |
| 144 | |
| 145 | p = q->prev; |
| 146 | n = q->next; |
| 147 | nn = n->next; |
| 148 | p->next = n; |
| 149 | n->prev = p; |
| 150 | n->next = q; |
| 151 | q->prev = n; |
| 152 | q->next = nn; |
| 153 | nn->prev = q; |
| 154 | ++delta; |
| 155 | --moved; |
| 156 | } |
| 157 | |
| 158 | if(moved) { |
| 159 | disorder_info("user %s moved %s", who, q->id); |
| 160 | notify_queue_move(q->track, who); |
| 161 | sprintf(buffer, "%d", moved); |
| 162 | eventlog("moved", who, (char *)0); |
| 163 | } |
| 164 | |
| 165 | return delta; |
| 166 | } |
| 167 | |
| 168 | void queue_moveafter(struct queue_entry *target, |
| 169 | int nqs, struct queue_entry **qs, |
| 170 | const char *who) { |
| 171 | struct queue_entry *q; |
| 172 | int n; |
| 173 | |
| 174 | /* Normalize */ |
| 175 | if(!target) |
| 176 | target = &qhead; |
| 177 | else |
| 178 | while(find_in_list(target, nqs, qs)) |
| 179 | target = target->prev; |
| 180 | /* Do the move */ |
| 181 | for(n = 0; n < nqs; ++n) { |
| 182 | q = qs[n]; |
| 183 | queue_delete_entry(q); |
| 184 | queue_insert_entry(target, q); |
| 185 | target = q; |
| 186 | /* Log the individual tracks */ |
| 187 | disorder_info("user %s moved %s", who, q->id); |
| 188 | notify_queue_move(q->track, who); |
| 189 | } |
| 190 | /* Report that the queue changed to the event log */ |
| 191 | eventlog("moved", who, (char *)0); |
| 192 | } |
| 193 | |
| 194 | void queue_remove(struct queue_entry *which, const char *who) { |
| 195 | if(who) { |
| 196 | disorder_info("user %s removed %s", who, which->id); |
| 197 | notify_queue_move(which->track, who); |
| 198 | } |
| 199 | eventlog("removed", which->id, who, (const char *)0); |
| 200 | queue_delete_entry(which); |
| 201 | } |
| 202 | |
| 203 | void queue_played(struct queue_entry *q) { |
| 204 | while(pcount && pcount >= config->history) { |
| 205 | eventlog("recent_removed", phead.next->id, (char *)0); |
| 206 | queue_delete_entry(phead.next); |
| 207 | pcount--; |
| 208 | } |
| 209 | if(config->history) { |
| 210 | eventlog_raw("recent_added", queue_marshall(q), (char *)0); |
| 211 | queue_insert_entry(phead.prev, q); |
| 212 | ++pcount; |
| 213 | } |
| 214 | } |
| 215 | |
| 216 | /* |
| 217 | Local Variables: |
| 218 | c-basic-offset:2 |
| 219 | comment-column:40 |
| 220 | fill-column:79 |
| 221 | indent-tabs-mode:nil |
| 222 | End: |
| 223 | */ |