wav_filter.c

   1 /*
   2  * Copyright (C) 2005-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file wav_filter.c A filter that inserts a wave header. */
   8
   9 #include <regex.h>
  10 #include <stdbool.h>
  11
  12 #include "para.h"
  13 #include "error.h"
  14 #include "list.h"
  15 #include "sched.h"
  16 #include "ggo.h"
  17 #include "buffer_tree.h"
  18 #include "filter.h"
  19 #include "string.h"
  20 #include "portable_io.h"
  21
  22 /** size of the output buffer */
  23 #define WAV_OUTBUF_SIZE 81920
  24 /** a wav header is always 44 bytes */
  25 #define WAV_HEADER_LEN 44
  26 /** always write 16 bit header */
  27 #define BITS 16
  28
  29 static void make_wav_header(unsigned int channels, unsigned int samplerate,
  30                 char *headbuf)
  31 {
  32
  33         unsigned int size = 0x7fffffff;
  34         int bytespersec = channels * samplerate * BITS / 8;
  35         int align = channels * BITS / 8;
  36
  37         PARA_DEBUG_LOG("writing wave header: %d channels, %d KHz\n", channels, samplerate);
  38         memset(headbuf, 0, WAV_HEADER_LEN);
  39         memcpy(headbuf, "RIFF", 4);
  40         write_u32(headbuf + 4, size - 8);
  41         memcpy(headbuf + 8, "WAVE", 4);
  42         memcpy(headbuf + 12, "fmt ", 4);
  43         write_u32(headbuf + 16, 16); /* 16 + extra format bytes (zero) */
  44         write_u16(headbuf + 20, 1);     /* format (1 == PCM/uncompressed) */
  45         write_u16(headbuf + 22, channels);
  46         write_u32(headbuf + 24, samplerate);
  47         write_u32(headbuf + 28, bytespersec);
  48         write_u16(headbuf + 32, align); /* number of bytes per sample slice */
  49         write_u16(headbuf + 34, BITS); /* significant bits per sample */
  50         memcpy(headbuf + 36, "data", 4); /* chunk ID */
  51         write_u32(headbuf + 40, size - 44); /* chunk size */
  52 }
  53
  54 static ssize_t wav_convert(char *inbuf, size_t len, struct filter_node *fn)
  55 {
  56         size_t copy;
  57         int *bof = fn->private_data;
  58
  59         if (*bof) {
  60                 if (!len)
  61                         return 0;
  62                 if (!fn->fc->channels || !fn->fc->samplerate) {
  63                         PARA_ERROR_LOG("%s\n", para_strerror(E_WAV_BAD_FC));
  64                         return -E_WAV_BAD_FC;
  65                 }
  66                 make_wav_header(fn->fc->channels, fn->fc->samplerate, fn->buf);
  67                 fn->loaded = WAV_HEADER_LEN;
  68                 *bof = 0;
  69 //              return 0;
  70         }
  71         copy = PARA_MIN(len, fn->bufsize - fn->loaded);
  72         memmove(fn->buf + fn->loaded, inbuf, copy);
  73         fn->loaded += copy;
  74 //      PARA_DEBUG_LOG("len = %d, copy = %d\n", len, copy);
  75         return copy;
  76 }
  77
  78 static void wav_close(struct filter_node *fn)
  79 {
  80         free(fn->buf);
  81         fn->buf = NULL;
  82         free(fn->private_data);
  83         fn->private_data = NULL;
  84 }
  85
  86 static void wav_open(struct filter_node *fn)
  87 {
  88         int *bof;
  89
  90         fn->bufsize = WAV_OUTBUF_SIZE;
  91         fn->buf = para_malloc(fn->bufsize);
  92         fn->private_data = para_malloc(sizeof(int));
  93         bof = fn->private_data;
  94         fn->loaded = 0;
  95         *bof = 1;
  96         PARA_INFO_LOG("wav filter node: %p, output buffer: %p, loaded: %zd\n",
  97                 fn, fn->buf, fn->loaded);
  98 }
  99
 100 static void wav_pre_select(struct sched *s, struct task *t)
 101 {
 102         struct filter_node *fn = container_of(t, struct filter_node, task);
 103         size_t iqs = btr_get_input_queue_size(fn->btrn);
 104
 105         t->error = 0;
 106         if (iqs == 0)
 107                 return;
 108         s->timeout.tv_sec = 0;
 109         s->timeout.tv_usec = 1;
 110 }
 111
 112 static void wav_post_select(__a_unused struct sched *s, struct task *t)
 113 {
 114         struct filter_node *fn = container_of(t, struct filter_node, task);
 115         struct btr_node *btrn = fn->btrn;
 116         size_t iqs = btr_get_input_queue_size(btrn);
 117         int ret;
 118         char *header, *buf;
 119         int32_t rate, ch;
 120
 121
 122         t->error = 0;
 123         if (iqs == 0) {
 124                 ret = -E_WAV_EOF;
 125                 if (btr_no_parent(btrn))
 126                         goto err;
 127                 return;
 128         }
 129         ret = btr_exec_up(btrn, "samplerate", &buf);
 130         if (ret < 0) {
 131                 ret = -E_WAV_BAD_FC;
 132                 goto err;
 133         }
 134         ret = para_atoi32(buf, &rate);
 135         free(buf);
 136         if (ret < 0)
 137                 goto err;
 138         ret = btr_exec_up(btrn, "channels", &buf);
 139         if (ret < 0) {
 140                 ret = -E_WAV_BAD_FC;
 141                 goto err;
 142         }
 143         ret = para_atoi32(buf, &ch);
 144         free(buf);
 145         if (ret < 0)
 146                 goto err;
 147         header = para_malloc(WAV_HEADER_LEN);
 148         make_wav_header(ch, rate, header);
 149         btr_add_output(header, WAV_HEADER_LEN, btrn);
 150         ret = -E_WAV_SUCCESS;
 151 err:
 152         t->error = ret;
 153         if (ret == -E_WAV_SUCCESS)
 154                 btr_splice_out_node(btrn);
 155         else {
 156                 btr_remove_node(btrn);
 157                 PARA_ERROR_LOG("%s\n", para_strerror(-ret));
 158         }
 159 }
 160
 161 /**
 162  * the init function of the wav filter
 163  *
 164  * \param f struct to initialize
 165  */
 166 void wav_filter_init(struct filter *f)
 167 {
 168         f->convert = wav_convert;
 169         f->close = wav_close;
 170         f->open = wav_open;
 171         f->pre_select = wav_pre_select;
 172         f->post_select = wav_post_select;
 173 }