owntone-server/src/wavstreamer.c

/*
 * -*- c -*-
 *
 * $Id$
 *
 * Read wav file from stdin and patch the info in header and write
 * it to stdout.
 *
 * Copyright (C) 2005 Timo J. Rinne (tri@iki.fi)
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include <ctype.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif

char *av0;

struct option longopts[] =
    { { "help",    0, NULL, 'h' },
      { "samples", 1, NULL, 's' },
      { "length",  1, NULL, 'l' },
      { "offset",  1, NULL, '0' },
      { NULL,      0, NULL,  0  } };

#define GET_WAV_INT32(p) ((((unsigned long)((p)[3])) << 24) |   \
                          (((unsigned long)((p)[2])) << 16) |   \
                          (((unsigned long)((p)[1])) <<  8) |   \
                          (((unsigned long)((p)[0]))))

#define GET_WAV_INT16(p) ((((unsigned long)((p)[1])) <<  8) |   \
                          (((unsigned long)((p)[0]))))

unsigned char *read_hdr(FILE *f, size_t *hdr_len)
{
    unsigned char *hdr;
    unsigned long format_data_length;

    hdr = malloc(256);
    if (hdr == NULL)
	return NULL;

    if (fread(hdr, 44, 1, f) != 1)
	goto fail;

    if (strncmp((char*)hdr + 12, "fmt ", 4))
	goto fail;

    format_data_length = GET_WAV_INT32(hdr + 16);

    if ((format_data_length < 16) || (format_data_length > 100))
	goto fail;

    *hdr_len = 44;

    if (format_data_length > 16) {
	if (fread(hdr + 44, format_data_length - 16, 1, f) != 1)
	    goto fail;
	*hdr_len += format_data_length - 16;
    }

    return hdr;

 fail:
    if (hdr != NULL)
	free(hdr);
    return NULL;
}

size_t parse_hdr(unsigned char *hdr, size_t hdr_len,
		 unsigned long *chunk_data_length_ret,
		 unsigned long *format_data_length_ret,
		 unsigned long *compression_code_ret,
		 unsigned long *channel_count_ret,
		 unsigned long *sample_rate_ret,
		 unsigned long *sample_bit_length_ret,
		 unsigned long *data_length_ret)
{
    unsigned long chunk_data_length;
    unsigned long format_data_length;
    unsigned long compression_code;
    unsigned long channel_count;
    unsigned long sample_rate;
    unsigned long sample_bit_length;
    unsigned long data_length;

    if (strncmp((char*)hdr + 0, "RIFF", 4) ||
	strncmp((char*)hdr + 8, "WAVE", 4) ||
	strncmp((char*)hdr + 12, "fmt ", 4))
	return 0;

    format_data_length = GET_WAV_INT32(hdr + 16);

    if (strncmp((char*)hdr + 20 + format_data_length, "data", 4))
	return 0;

    chunk_data_length = GET_WAV_INT32(hdr + 4);
    compression_code = GET_WAV_INT16(hdr + 20);
    channel_count = GET_WAV_INT16(hdr + 22);
    sample_rate = GET_WAV_INT32(hdr + 24);
    sample_bit_length = GET_WAV_INT16(hdr + 34);
    data_length = GET_WAV_INT32(hdr + 20 + format_data_length + 4);
  
    if ((format_data_length != 16) ||
	(compression_code != 1) ||
	(channel_count < 1) ||
	(sample_rate == 0) ||
	(sample_rate > 512000) ||
	(sample_bit_length < 2))
	return 0;

    *chunk_data_length_ret = chunk_data_length;
    *format_data_length_ret = format_data_length;
    *compression_code_ret = compression_code;
    *channel_count_ret = channel_count;
    *sample_rate_ret = sample_rate;
    *sample_bit_length_ret = sample_bit_length;
    *data_length_ret = data_length;

    return 20 + format_data_length + 8;
}

size_t patch_hdr(unsigned char *hdr, size_t hdr_len,
		 unsigned long sec, unsigned long us,
		 unsigned long samples,
		 size_t *data_length_ret)
{
    unsigned long chunk_data_length;
    unsigned long format_data_length;
    unsigned long compression_code;
    unsigned long channel_count;
    unsigned long sample_rate;
    unsigned long sample_bit_length;
    unsigned long data_length;
    unsigned long bytes_per_sample;

    if (parse_hdr(hdr, hdr_len,
		  &chunk_data_length,
		  &format_data_length,
		  &compression_code,
		  &channel_count,
		  &sample_rate,
		  &sample_bit_length,
		  &data_length) != hdr_len)
	return 0;

    if (hdr_len != (20 + format_data_length + 8))
	return 0;

    if (format_data_length > 16) {
	memmove(hdr + 20 + 16, hdr + 20 + format_data_length, 8);
	hdr[16] = 16;
	hdr[17] = 0;
	hdr[18] = 0;
	hdr[19] = 0;
	format_data_length = 16;
	hdr_len = 44;
    }

    bytes_per_sample = channel_count * ((sample_bit_length + 7) / 8);

    if (samples == 0) {
	samples = sample_rate * sec;
	samples += ((sample_rate / 100) * (us / 10)) / 1000;
    }

    if (samples > 0) {
	data_length = samples * bytes_per_sample;
	chunk_data_length = data_length + 36;
    } else {
	chunk_data_length = 0xffffffff;
	data_length = chunk_data_length - 36;
    }

    if (data_length_ret != NULL)
	*data_length_ret = data_length;

    hdr[4] = chunk_data_length % 0x100;
    hdr[5] = (chunk_data_length >> 8) % 0x100;
    hdr[6] = (chunk_data_length >> 16) % 0x100;
    hdr[7] = (chunk_data_length >> 24) % 0x100;

    hdr[40] = data_length % 0x100;
    hdr[41] = (data_length >> 8) % 0x100;
    hdr[42] = (data_length >> 16) % 0x100;
    hdr[43] = (data_length >> 24) % 0x100;

    return hdr_len;
}

static void usage(int exitval);

static void usage(int exitval)
{
    fprintf(stderr,
	    "Usage: %s [ options ] [input-file]\n", av0);
    fprintf(stderr,
	    "\n");
    fprintf(stderr,
	    "Options:\n");
    fprintf(stderr,
	    "-l len    |  --length=len     Length of the sound file in seconds.\n");
    fprintf(stderr,
	    "-s len    |  --samples=len    Length of the sound file in samples.\n");
    fprintf(stderr,
	    "-o offset |  --offset=offset  Number of bytes to discard from the stream.\n");
    fprintf(stderr,
	    "\n");
    fprintf(stderr,
	    "--samples and --length are mutually exclusive.\n");

#ifndef HAVE_GETOPT_H
    fprintf(stderr,
	    "\n\nLong options are not availabl eon this system.\n");
#endif

    exit(exitval);
}

int main(int argc, char **argv)
{
    int c;
    unsigned long sec = 0, us = 0, samples = 0;
    unsigned long offset = 0;
    char *end;
    FILE *f=NULL;
    unsigned char *hdr;
    size_t hdr_len;
    size_t data_len;
    unsigned char buf[0x1000];
    size_t buf_len;

    if (strchr(argv[0], '/'))
	av0 = strrchr(argv[0], '/') + 1;
    else
	av0 = argv[0];

#ifdef HAVE_GETOPT_H
    while ((c = getopt_long(argc, argv, "+hl:o:s:", longopts, NULL)) != EOF) {
#else
    while ((c = getopt(argc, argv, "hl:o:s:")) != -1) {
#endif
	switch(c) {
	case 'h': 
	    usage(0);
	    /*NOTREACHED*/
	    break;
	    
	case 'l':
	    sec = strtoul(optarg, &end, 10);
	    if ((*optarg == '-') || (end == optarg) || ((*end != '\0') && (*end != '.'))) {
		fprintf(stderr, "%s: Invalid -l argument.\n", av0);
		exit(-1);
	    } else if (*end == '.') {
		char tmp[7];
		int i;
		
		memset(tmp, '0', sizeof (tmp) - 1);
		tmp[sizeof (tmp) - 1] = '\0';
		for (i = 0; (i < (sizeof (tmp) - 1)) && (isdigit(end[i+1])); i++)
		    tmp[i] = end[i+1];
		us = strtoul(tmp, NULL, 10);
	    } else {
		us = 0;
	    }

	    if ((sec == 0) && (us == 0)) {
		fprintf(stderr, "%s: Invalid -l argument (zero is not acceptable).\n", av0);
		exit(-1);
	    }

	    if (samples != 0) {
		fprintf(stderr, "%s: Parameters -s and -l are mutually exclusive.\n", av0);
		exit(-1);
	    }
	    break;
	    
	case 's':
	    samples = strtoul(optarg, &end, 10);
	    if ((*optarg == '-') || (end == optarg) || (*end != '\0')) {
		fprintf(stderr, "%s: Invalid -s argument.\n", av0);
		exit(-1);
	    }
	    if (samples == 0) {
		fprintf(stderr, "%s: Invalid -s argument (zero is not acceptable).\n", av0);
		exit(-1);
	    }
	    if ((sec != 0) || (us != 0)) {
		fprintf(stderr, "%s: Parameters -l and -s are mutually exclusive.\n", av0);
		exit(-1);
	    }
	    break;
	    
	case 'o':
	    offset = strtoul(optarg, &end, 10);
	    if ((*optarg == '-') || (end == optarg) || (*end != '\0')) {
		fprintf(stderr, "%s: Invalid -o argument.\n", av0);
		exit(-1);
	    }
	    break;
	    
	default:
	    fprintf(stderr, "%s: Bad command line option -%c.\n", av0, optopt);
	    usage(-1);
	}
    }
    
    argc -= optind;
    argv += optind;

    if (argc == 0) {
	f = stdin;
    } else if (argc == 1) {
	f = fopen(argv[0], "rb");
	if (f == NULL) {
	    fprintf(stderr, "%s: Can't open file %s for reading.\n", av0, argv[0]);
	    exit(1);
	}
    } else {
	fprintf(stderr, "%s: Too many command line arguments.\n", av0);
	usage(-1);
    }

    hdr = read_hdr(f, &hdr_len);
    if (hdr == NULL) {
	fprintf(stderr, "%s: Can't read wav header.\n", av0);
	exit(2);
    }
    if ((hdr_len = patch_hdr(hdr, hdr_len, sec, us, samples, &data_len)) == 0) {
	free(hdr);
	fprintf(stderr, "%s: Can't parse (or patch) wav header.\n", av0);
	exit(2);
    }

    if (offset > hdr_len + data_len) {
	fprintf(stderr, "%s: Offset is beyond EOF.\n", av0);
	exit(3);
    }

    if ((offset > 0) && (offset < hdr_len)) {
	memmove(hdr, hdr + offset, hdr_len - offset);
	hdr_len -= offset;
	offset = 0;
    } 

    if (offset > 0) {
	offset -= hdr_len;
    } else {
	if (fwrite(hdr, hdr_len, 1, stdout) != 1) {
	    fprintf(stderr, "%s: Write failed.\n", av0);
	    exit(4);
	}
    }

    free(hdr);
    hdr = NULL;
    hdr_len = 0;

    if (offset > 0) {
	data_len -= offset;
	while (offset > 0) {
	    buf_len = (offset > sizeof (buf)) ? sizeof (buf) : offset;
	    if (fread(buf, buf_len, 1, f) != 1) {
		fprintf(stderr, "%s: Read failed.\n", av0);
		exit(5);
	    }
	    offset -= buf_len;
	}
    }

    while (data_len > 0) {
	buf_len = (data_len > sizeof (buf)) ? sizeof (buf) : data_len;
	if (fread(buf, buf_len, 1, f) != 1) {
	    fprintf(stderr, "%s: Read failed.\n", av0);
	    exit(5);
	}
	if (fwrite(buf, buf_len, 1, stdout) != 1) {
	    fprintf(stderr, "%s: Write failed.\n", av0);
	    exit(4);
	}
	data_len -= buf_len;
    }

    if (f != stdout) {
	fclose(f);
    }
    exit(0);
}