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/*
** Copyright 2010, The Android Open-Source Project
**
** Licensed under the Apache License, Version 2.0 (the "License");
** you may not use this file except in compliance with the License.
** You may obtain a copy of the License at
**
** http://www.apache.org/licenses/LICENSE-2.0
**
** Unless required by applicable law or agreed to in writing, software
** distributed under the License is distributed on an "AS IS" BASIS,
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
** See the License for the specific language governing permissions and
** limitations under the License.
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdint.h>
#include <string.h>
#include "alsa_audio.h"
#define ID_RIFF 0x46464952
#define ID_WAVE 0x45564157
#define ID_FMT 0x20746d66
#define ID_DATA 0x61746164
#define FORMAT_PCM 1
struct wav_header {
uint32_t riff_id;
uint32_t riff_sz;
uint32_t riff_fmt;
uint32_t fmt_id;
uint32_t fmt_sz;
uint16_t audio_format;
uint16_t num_channels;
uint32_t sample_rate;
uint32_t byte_rate; /* sample_rate * num_channels * bps / 8 */
uint16_t block_align; /* num_channels * bps / 8 */
uint16_t bits_per_sample;
uint32_t data_id;
uint32_t data_sz;
};
int record_file(unsigned rate, unsigned channels, int fd, unsigned count)
{
struct pcm *pcm;
unsigned avail, xfer, bufsize;
char *data, *next;
int r;
pcm = pcm_open(PCM_IN|PCM_MONO);
if (!pcm_ready(pcm)) {
pcm_close(pcm);
goto fail;
}
bufsize = pcm_buffer_size(pcm);
data = malloc(bufsize);
if (!data) {
fprintf(stderr,"could not allocate %d bytes\n", count);
return -1;
}
while (!pcm_read(pcm, data, bufsize)) {
if (write(fd, data, bufsize) != bufsize) {
fprintf(stderr,"could not write %d bytes\n", bufsize);
return -1;
}
}
close(fd);
pcm_close(pcm);
return 0;
fail:
fprintf(stderr,"pcm error: %s\n", pcm_error(pcm));
return -1;
}
int rec_wav(const char *fn)
{
struct wav_header hdr;
unsigned rate, channels;
int fd;
fd = open(fn, O_WRONLY | O_CREAT | O_TRUNC, 0664);
if (fd < 0) {
fprintf(stderr, "arec: cannot open '%s'\n", fn);
return -1;
}
hdr.riff_id = ID_RIFF;
hdr.riff_fmt = ID_WAVE;
hdr.fmt_id = ID_FMT;
hdr.audio_format = FORMAT_PCM;
hdr.fmt_sz = 16;
hdr.bits_per_sample = 16;
hdr.num_channels = 1;
hdr.data_sz = 0;
hdr.sample_rate = 44100;
if (write(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
fprintf(stderr, "arec: cannot write header\n");
return -1;
}
fprintf(stderr,"arec: %d ch, %d hz, %d bit, %s\n",
hdr.num_channels, hdr.sample_rate, hdr.bits_per_sample,
hdr.audio_format == FORMAT_PCM ? "PCM" : "unknown");
return record_file(hdr.sample_rate, hdr.num_channels, fd, hdr.data_sz);
}
int main(int argc, char **argv)
{
if (argc != 2) {
fprintf(stderr,"usage: arec <file>\n");
return -1;
}
return rec_wav(argv[1]);
}
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