mpd/src/queue.c
Max Kellermann a0a26d3341 Merge release 0.15.8 from branch 'v0.15.x
Conflicts:
	Makefile.am
	NEWS
	configure.ac
	src/decoder/ffmpeg_decoder_plugin.c
	src/decoder_thread.c
2010-01-18 07:52:58 +01:00

345 lines
8.1 KiB
C

/*
* Copyright (C) 2003-2010 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "queue.h"
#include "song.h"
/**
* Generate a non-existing id number.
*/
static unsigned
queue_generate_id(const struct queue *queue)
{
static unsigned cur = (unsigned)-1;
do {
cur++;
if (cur >= queue->max_length * QUEUE_HASH_MULT)
cur = 0;
} while (queue->id_to_position[cur] != -1);
return cur;
}
int
queue_next_order(const struct queue *queue, unsigned order)
{
assert(order < queue->length);
if (queue->single)
{
if (queue->repeat && !queue->consume)
return order;
else
return -1;
}
if (order + 1 < queue->length)
return order + 1;
else if (queue->repeat && (order > 0 || !queue->consume))
/* restart at first song */
return 0;
else
/* end of queue */
return -1;
}
void
queue_increment_version(struct queue *queue)
{
static unsigned long max = ((uint32_t) 1 << 31) - 1;
queue->version++;
if (queue->version >= max) {
for (unsigned i = 0; i < queue->length; i++)
queue->items[i].version = 0;
queue->version = 1;
}
}
void
queue_modify(struct queue *queue, unsigned order)
{
unsigned position;
assert(order < queue->length);
position = queue->order[order];
queue->items[position].version = queue->version;
queue_increment_version(queue);
}
void
queue_modify_all(struct queue *queue)
{
for (unsigned i = 0; i < queue->length; i++)
queue->items[i].version = queue->version;
queue_increment_version(queue);
}
unsigned
queue_append(struct queue *queue, struct song *song)
{
unsigned id = queue_generate_id(queue);
assert(!queue_is_full(queue));
queue->items[queue->length] = (struct queue_item){
.song = song,
.id = id,
.version = queue->version,
};
queue->order[queue->length] = queue->length;
queue->id_to_position[id] = queue->length;
++queue->length;
return id;
}
void
queue_swap(struct queue *queue, unsigned position1, unsigned position2)
{
struct queue_item tmp;
unsigned id1 = queue->items[position1].id;
unsigned id2 = queue->items[position2].id;
tmp = queue->items[position1];
queue->items[position1] = queue->items[position2];
queue->items[position2] = tmp;
queue->items[position1].version = queue->version;
queue->items[position2].version = queue->version;
queue->id_to_position[id1] = position2;
queue->id_to_position[id2] = position1;
}
static void
queue_move_song_to(struct queue *queue, unsigned from, unsigned to)
{
unsigned from_id = queue->items[from].id;
queue->items[to] = queue->items[from];
queue->items[to].version = queue->version;
queue->id_to_position[from_id] = to;
}
void
queue_move(struct queue *queue, unsigned from, unsigned to)
{
struct queue_item item = queue->items[from];
/* move songs to one less in from->to */
for (unsigned i = from; i < to; i++)
queue_move_song_to(queue, i + 1, i);
/* move songs to one more in to->from */
for (unsigned i = from; i > to; i--)
queue_move_song_to(queue, i - 1, i);
/* put song at _to_ */
queue->id_to_position[item.id] = to;
queue->items[to] = item;
queue->items[to].version = queue->version;
/* now deal with order */
if (queue->random) {
for (unsigned i = 0; i < queue->length; i++) {
if (queue->order[i] > from && queue->order[i] <= to)
queue->order[i]--;
else if (queue->order[i] < from &&
queue->order[i] >= to)
queue->order[i]++;
else if (from == queue->order[i])
queue->order[i] = to;
}
}
}
void
queue_move_range(struct queue *queue, unsigned start, unsigned end, unsigned to)
{
struct queue_item items[end - start];
// Copy the original block [start,end-1]
for (unsigned i = start; i < end; i++)
items[i - start] = queue->items[i];
// If to > start, we need to move to-start items to start, starting from end
for (unsigned i = end; i < end + to - start; i++)
queue_move_song_to(queue, i, start + i - end);
// If to < start, we need to move start-to items to newend (= end + to - start), starting from to
// This is the same as moving items from start-1 to to (decreasing), with start-1 going to end-1
// We have to iterate in this order to avoid writing over something we haven't yet moved
for (unsigned i = start - 1; i >= to && i != G_MAXUINT; i--)
queue_move_song_to(queue, i, i + end - start);
// Copy the original block back in, starting at to.
for (unsigned i = start; i< end; i++)
{
queue->id_to_position[items[i-start].id] = to + i - start;
queue->items[to + i - start] = items[i-start];
queue->items[to + i - start].version = queue->version;
}
if (queue->random) {
// Update the positions in the queue.
// Note that the ranges for these cases are the same as the ranges of
// the loops above.
for (unsigned i = 0; i < queue->length; i++) {
if (queue->order[i] >= end && queue->order[i] < to + end - start)
queue->order[i] -= end - start;
else if (queue->order[i] < start &&
queue->order[i] >= to)
queue->order[i] += end - start;
else if (start <= queue->order[i] && queue->order[i] < end)
queue->order[i] += to - start;
}
}
}
void
queue_delete(struct queue *queue, unsigned position)
{
struct song *song;
unsigned id, order;
assert(position < queue->length);
song = queue_get(queue, position);
if (!song_in_database(song))
song_free(song);
id = queue_position_to_id(queue, position);
order = queue_position_to_order(queue, position);
--queue->length;
/* release the song id */
queue->id_to_position[id] = -1;
/* delete song from songs array */
for (unsigned i = position; i < queue->length; i++)
queue_move_song_to(queue, i + 1, i);
/* delete the entry from the order array */
for (unsigned i = order; i < queue->length; i++)
queue->order[i] = queue->order[i + 1];
/* readjust values in the order array */
for (unsigned i = 0; i < queue->length; i++)
if (queue->order[i] > position)
--queue->order[i];
}
void
queue_clear(struct queue *queue)
{
for (unsigned i = 0; i < queue->length; i++) {
struct queue_item *item = &queue->items[i];
if (!song_in_database(item->song))
song_free(item->song);
queue->id_to_position[item->id] = -1;
}
queue->length = 0;
}
void
queue_init(struct queue *queue, unsigned max_length)
{
queue->max_length = max_length;
queue->length = 0;
queue->version = 1;
queue->repeat = false;
queue->random = false;
queue->single = false;
queue->consume = false;
queue->items = g_new(struct queue_item, max_length);
queue->order = g_malloc(sizeof(queue->order[0]) *
max_length);
queue->id_to_position = g_malloc(sizeof(queue->id_to_position[0]) *
max_length * QUEUE_HASH_MULT);
for (unsigned i = 0; i < max_length * QUEUE_HASH_MULT; ++i)
queue->id_to_position[i] = -1;
queue->rand = g_rand_new();
}
void
queue_finish(struct queue *queue)
{
queue_clear(queue);
g_free(queue->items);
g_free(queue->order);
g_free(queue->id_to_position);
g_rand_free(queue->rand);
}
void
queue_shuffle_order(struct queue *queue)
{
assert(queue->random);
for (unsigned i = 0; i < queue->length; i++)
queue_swap_order(queue, i,
g_rand_int_range(queue->rand, i,
queue->length));
}
void
queue_shuffle_order_last(struct queue *queue, unsigned start, unsigned end)
{
queue_swap_order(queue, end - 1,
g_rand_int_range(queue->rand, start, end));
}
void
queue_shuffle_range(struct queue *queue, unsigned start, unsigned end)
{
assert(start <= end);
assert(end <= queue->length);
for (unsigned i = start; i < end; i++) {
unsigned ri = g_rand_int_range(queue->rand, i, end);
queue_swap(queue, i, ri);
}
}