track.h

   1 /*
   2  * Copyright (C) 2008 Mark Hills <mark@pogo.org.uk>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License version 2 for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * version 2 along with this program; if not, write to the Free
  15  * Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  16  * MA 02110-1301, USA.
  17  *
  18  */
  19
  20 #ifndef TRACK_H
  21 #define TRACK_H
  22
  23 #include <pthread.h>
  24 #include <sys/poll.h>
  25 #include <sys/types.h>
  26 #include <glib.h>
  27
  28 #include "rig.h"
  29
  30 struct cached_file;
  31 struct cache_read;
  32
  33 #define TRACK_CHANNELS 2
  34 #define TRACK_RATE 44100
  35
  36 #define TRACK_STATUS_UNKNOWN -1
  37 #define TRACK_STATUS_VALID 0
  38 #define TRACK_STATUS_IMPORTING 1
  39
  40 /*#define TRACK_MAX_BLOCKS 64*/
  41 #define TRACK_BLOCK_SAMPLES (2048 * 1024)
  42 #define TRACK_PPM_RES 64
  43 #define TRACK_OVERVIEW_RES 2048
  44
  45 #define BYTES_PER_SAMPLE (TRACK_CHANNELS * sizeof(signed short)) /* bytes per sample (all channels) */
  46
  47 //pcm elements a track block holds
  48 #define TRACK_BLOCK_PCM_LENGTH (TRACK_BLOCK_SAMPLES * TRACK_CHANNELS)
  49 #define BYTES_PER_PCM_BLOCK (TRACK_BLOCK_SAMPLES * BYTES_PER_SAMPLE)
  50 typedef signed short TRACK_PCM_DATA_TYPE;
  51 #define TRACK_PCM_DATA_SIZE sizeof(TRACK_PCM_DATA_TYPE)
  52
  53 #define TRACK_PPM_LENGTH TRACK_BLOCK_SAMPLES / TRACK_PPM_RES
  54 #define TRACK_OVERVIEW_LENGTH TRACK_BLOCK_SAMPLES / TRACK_OVERVIEW_RES
  55
  56 struct track_block_t {
  57     TRACK_PCM_DATA_TYPE pcm[TRACK_BLOCK_PCM_LENGTH];
  58     unsigned char ppm[TRACK_PPM_LENGTH],
  59         overview[TRACK_OVERVIEW_LENGTH];
  60 };
  61
  62 struct track_t {
  63     int status, fd, eof;
  64     pid_t pid;
  65     struct pollfd *pe;
  66     pthread_mutex_t mx;
  67     struct rig_t *rig;
  68
  69     /* pointers to external data */
  70
  71     const char *importer, /* path to import script */
  72         *artist, *title, *name;
  73
  74     size_t bytes; /* loaded in */
  75     guint /*length, track length in samples */
  76         blocks; /* number of blocks allocated */
  77     GPtrArray *block;
  78
  79     /* Current value of audio meters when loading */
  80
  81     unsigned short ppm;
  82     unsigned int overview;
  83
  84     struct cached_track* cache;
  85     struct cache_read* cache_read;
  86 };
  87
  88 void track_init(struct track_t *tr, const char *importer);
  89 int track_clear(struct track_t *tr);
  90 int track_import(struct track_t *tr, const char *path);
  91 int track_pollfd(struct track_t *tr, struct pollfd *pe);
  92 int track_handle(struct track_t *tr);
  93 int track_abort(struct track_t *tr);
  94 int track_wait(struct track_t *tr);
  95 guint track_get_sample_count(const struct track_t* tr);
  96
  97 guint track_block_get_used_bytes(const struct track_t* tr, const guint index);
  98
  99 /* Macro functions, to force the code inline */
 100
 101 #define track_get_block(tr, i) \
 102         ((struct track_block_t*)g_ptr_array_index((tr)->block, i))
 103
 104 #define track_get_ppm(tr, s) \
 105     track_get_block(tr, (s) / TRACK_BLOCK_SAMPLES) \
 106      ->ppm[((s) % TRACK_BLOCK_SAMPLES) / TRACK_PPM_RES]
 107
 108 #define track_get_overview(tr, s) \
 109     track_get_block(tr, (s) / TRACK_BLOCK_SAMPLES) \
 110      ->overview[((s) % TRACK_BLOCK_SAMPLES) / TRACK_OVERVIEW_RES]
 111
 112 /* Return a pointer to (not value of) the sample data for each channel */
 113
 114 #define track_get_sample(tr, s) \
 115     &track_get_block(tr, (s) / TRACK_BLOCK_SAMPLES)->pcm[((s) % TRACK_BLOCK_SAMPLES) \
 116                                                   * TRACK_CHANNELS]
 117
 118 #endif
 119