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/* libdax_audioxtr
Audio track data extraction facility of libdax and libburn.
Copyright (C) 2006 Thomas Schmitt <scdbackup@gmx.net>, provided under GPLv2+
*/
#ifdef HAVE_CONFIG_H
#include "../config.h"
#endif
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
/* ts B41126 : O_BINARY is needed for Cygwin but undefined elsewhere */
#ifndef O_BINARY
#define O_BINARY 0
#endif
#include "libdax_msgs.h"
extern struct libdax_msgs *libdax_messenger;
/* Only this single source module is entitled to do this */
#define LIBDAX_AUDIOXTR_H_INTERNAL 1
/* All clients of the extraction facility must do this or include libburn.h */
#define LIBDAX_AUDIOXTR_H_PUBLIC 1
#include "libdax_audioxtr.h"
int libdax_audioxtr_new(struct libdax_audioxtr **xtr, char *path, int flag)
{
int ret= -1;
struct libdax_audioxtr *o;
o= *xtr= (struct libdax_audioxtr *) calloc(1, sizeof(struct libdax_audioxtr));
if(o==NULL)
return(-1);
strncpy(o->path,path,LIBDAX_AUDIOXTR_STRLEN-1);
o->path[LIBDAX_AUDIOXTR_STRLEN-1]= 0;
o->fd= -1;
strcpy(o->fmt,"unidentified");
o->fmt_info[0]= 0;
o->data_size= 0;
o->extract_count= 0;
o->num_channels= 0;
o->sample_rate= 0;
o->bits_per_sample= 0;
o->msb_first= 0;
o->wav_data_location= 44;
o->wav_subchunk2_size= 0;
o->au_data_location= 0;
o->au_data_size= 0xffffffff;
ret= libdax_audioxtr_open(o,0);
if(ret<=0)
{ret= -2*(ret<0); goto failure;}
return(1);
failure:
libdax_audioxtr_destroy(xtr,0);
return(ret);
}
int libdax_audioxtr_destroy(struct libdax_audioxtr **xtr, int flag)
{
struct libdax_audioxtr *o;
o= *xtr;
if(o==NULL)
return(0);
if(o->fd>=0 && strcmp(o->path,"-")!=0)
close(o->fd);
free((char *) o);
*xtr= NULL;
return(1);
}
static int libdax_audioxtr_open(struct libdax_audioxtr *o, int flag)
{
int ret;
char msg[LIBDAX_AUDIOXTR_STRLEN+80];
if(strcmp(o->path,"-")==0)
o->fd= 0;
else
o->fd= open(o->path, O_RDONLY | O_BINARY);
if(o->fd<0) {
sprintf(msg,"Cannot open audio source file : %s",o->path);
libdax_msgs_submit(libdax_messenger,-1,0x00020200,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
msg, errno, 0);
return(-1);
}
ret= libdax_audioxtr_identify(o,0);
if(ret<=0) {
sprintf(msg,"Audio source file has unsuitable format : %s",o->path);
libdax_msgs_submit(libdax_messenger,-1,0x00020201,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
msg, 0, 0);
return(0);
}
ret= libdax_audioxtr_init_reading(o,0);
if(ret<=0) {
sprintf(msg,"Failed to prepare reading of audio data : %s",o->path);
libdax_msgs_submit(libdax_messenger,-1,0x00020202,
LIBDAX_MSGS_SEV_SORRY, LIBDAX_MSGS_PRIO_HIGH,
msg, 0, 0);
return(0);
}
return(1);
}
/* @param flag: bit0= sequential file, skip by reading data
*/
static int libdax_audioxtr_skip(struct libdax_audioxtr *o,
off_t *old_pos,
off_t pos, int flag)
{
int ret;
size_t to_read;
static char buf[256]; /* Thread safe because the content does not matter */
if((flag & 1) || o->fd == 0) { /* stdin */
while(pos - *old_pos > 0) {
to_read= pos - *old_pos;
if(to_read > sizeof(buf))
to_read= sizeof(buf);
ret= read(o->fd, buf, to_read);
if(ret < (int) to_read)
return(0);
*old_pos+= to_read;
}
} else {
ret= lseek(o->fd, pos, SEEK_SET);
if(ret == -1)
return(0);
*old_pos= pos;
}
return(1);
}
static int libdax_audioxtr_identify_wav(struct libdax_audioxtr *o, int flag)
{
int ret, fmt_seen= 0, data_seen= 0;
off_t pos= 0, old_pos= 0, riff_end= 0;
char buf[16];
unsigned char *ubuf;
/* check whether this is a MS WAVE file .wav */
/* info used: http://ccrma.stanford.edu/courses/422/projects/WaveFormat/
https://en.wikipedia.org/wiki/WAV
see summary in: doc/waveformat.txt
*/
ubuf= (unsigned char *) buf;
/* Look for ChunkID "RIFF" , tolerate other known chunks */
while(1) {
ret= libdax_audioxtr_skip(o, &old_pos, pos, 0);
if(ret <= 0)
return(0);
ret= read(o->fd, buf, 8);
if(ret < 8)
return(0);
old_pos+= 8;
pos= old_pos + libdax_audioxtr_to_int(o, ubuf + 4, 4, 0);
if(pos > 0xffffffff || pos - old_pos < 4) /* Too large or no Format word */
return(0);
if(strncmp(buf, "RIFF", 4) == 0)
break;
/* Wikipedia mentions these known ChunkId values */
if(strncmp(buf, "INFO", 4) == 0 ||
strncmp(buf, "CSET", 4) == 0 ||
strncmp(buf, "JUNK", 4) == 0 ||
strncmp(buf, "PAD ", 4) == 0)
continue;
return(0);
}
/* Read RIFF Format header */
ret= read(o->fd, buf, 4);
if(ret < 4)
return(0);
old_pos+= 4;
if(strncmp(buf, "WAVE", 4) != 0) /* Format */
return(0);
riff_end= pos;
/* Look for SubchunkID "fmt " and "data" */
pos= old_pos;
while(old_pos < riff_end) {
ret= libdax_audioxtr_skip(o, &old_pos, pos, 0);
if(ret <= 0)
return(0);
ret= read(o->fd, buf, 8);
if(ret < 8)
return(0);
old_pos= pos + 8;
pos= old_pos + libdax_audioxtr_to_int(o, ubuf + 4, 4, 0); /* SubchunkSize */
if(strncmp(buf,"fmt ", 4) == 0) {
if(pos - old_pos < 16)
return(0);
ret= read(o->fd, buf, 16);
if(ret < 16)
return(0);
old_pos+= 16;
if(buf[0]!=1 || buf[1]!=0) /* AudioFormat (1 = Linear quantization) */
return(0);
o->msb_first= 0;
o->num_channels= libdax_audioxtr_to_int(o, ubuf + 2 , 2, 0);
o->sample_rate= libdax_audioxtr_to_int(o, ubuf + 4, 4, 0);
o->bits_per_sample= libdax_audioxtr_to_int(o, ubuf + 14, 2, 0);
sprintf(o->fmt_info,
".wav , num_channels=%d , sample_rate=%d , bits_per_sample=%d",
o->num_channels, o->sample_rate, o->bits_per_sample);
fmt_seen= 1;
} else if(strncmp(buf,"data", 4) == 0) {
o->wav_data_location= old_pos;
o->wav_subchunk2_size= pos - old_pos;
o->data_size= o->wav_subchunk2_size;
data_seen= 1;
}
if(fmt_seen && data_seen) {
strcpy(o->fmt,".wav");
return(1);
}
}
return(0);
}
static int libdax_audioxtr_identify_au(struct libdax_audioxtr *o, int flag)
{
int ret,encoding;
char buf[24];
/* Check whether this is a Sun Audio, .au file */
/* info used: http://ccrma.stanford.edu/courses/422/projects/WaveFormat/ */
if(o->fd!=0) {
ret= lseek(o->fd,0,SEEK_SET);
if(ret==-1)
return(0);
}
ret= read(o->fd, buf, 24);
if(ret<24)
return(0);
if(strncmp(buf,".snd",4)!=0)
return(0);
strcpy(o->fmt,".au");
o->msb_first= 1;
o->au_data_location= libdax_audioxtr_to_int(o,(unsigned char *)buf+4,4,1);
o->au_data_size= libdax_audioxtr_to_int(o,(unsigned char *)buf+8,4,1);
encoding= libdax_audioxtr_to_int(o,(unsigned char *)buf+12,4,1);
if(encoding==2)
o->bits_per_sample= 8;
else if(encoding==3)
o->bits_per_sample= 16;
else if(encoding==4)
o->bits_per_sample= 24;
else if(encoding==5)
o->bits_per_sample= 32;
else
o->bits_per_sample= -encoding;
o->sample_rate= libdax_audioxtr_to_int(o,(unsigned char *)buf+16,4,1);
o->num_channels= libdax_audioxtr_to_int(o,(unsigned char *)buf+20,4,1);
if(o->au_data_size!=0xffffffff)
o->data_size= o->au_data_size;
else
o->data_size= 0;
sprintf(o->fmt_info,
".au , num_channels=%d , sample_rate=%d , bits_per_sample=%d",
o->num_channels,o->sample_rate,o->bits_per_sample);
return(o->bits_per_sample>0); /* Audio format must be linear PCM */
}
static int libdax_audioxtr_identify(struct libdax_audioxtr *o, int flag)
{
int ret;
ret= libdax_audioxtr_identify_wav(o, 0);
if(ret!=0)
return(ret);
if(o->fd==0) /* cannot rewind stdin */
return(0);
ret= libdax_audioxtr_identify_au(o, 0);
if(ret!=0)
return(ret);
return(0);
}
/* @param flag bit0=msb_first */
static unsigned libdax_audioxtr_to_int(struct libdax_audioxtr *o,
unsigned char *bytes, int len, int flag)
{
unsigned int ret= 0;
int i;
if(flag&1)
for(i= 0; i<len; i++)
ret= ret*256+bytes[i];
else
for(i= len-1; i>=0; i--)
ret= ret*256+bytes[i];
return(ret);
}
static int libdax_audioxtr_init_reading(struct libdax_audioxtr *o, int flag)
{
int ret;
/* currently this only works for MS WAVE files .wav and Sun .au*/;
if(o->fd==0) /* stdin: hope no read came after libdax_audioxtr_identify() */
return(1);
o->extract_count= 0;
if(strcmp(o->fmt,".wav")==0)
ret= lseek(o->fd, o->wav_data_location, SEEK_SET);
else if(strcmp(o->fmt,".au")==0)
ret= lseek(o->fd,o->au_data_location,SEEK_SET);
else
ret= -1;
if(ret==-1)
return(0);
return(1);
}
int libdax_audioxtr_get_id(struct libdax_audioxtr *o,
char **fmt, char **fmt_info,
int *num_channels, int *sample_rate, int *bits_per_sample,
int *msb_first, int flag)
{
*fmt= o->fmt;
*fmt_info= o->fmt_info;
*num_channels= o->num_channels;
*sample_rate= o->sample_rate;
*bits_per_sample= o->bits_per_sample;
*msb_first= o->msb_first;
return(1);
}
int libdax_audioxtr_get_size(struct libdax_audioxtr *o, off_t *size, int flag)
{
*size= o->data_size;
return(1);
}
int libdax_audioxtr_read(struct libdax_audioxtr *o,
char buffer[], int buffer_size, int flag)
{
int ret;
if(buffer_size<=0 || o->fd<0)
return(-2);
if(o->data_size>0 && !(flag&1))
if(buffer_size > o->data_size - o->extract_count)
buffer_size= o->data_size - o->extract_count;
if(buffer_size<=0)
return(0);
ret= read(o->fd,buffer,buffer_size);
if(ret>0)
o->extract_count+= ret;
return(ret);
}
int libdax_audioxtr_detach_fd(struct libdax_audioxtr *o, int *fd, int flag)
{
if(o->fd<0)
return(-1);
if(strcmp(o->fmt,".wav")!=0 && strcmp(o->fmt,".au")!=0)
return(0);
if(flag&1) {
*fd= o->fd;
} else {
*fd= dup(o->fd);
if(*fd>=0 && strcmp(o->path,"-")!=0)
close(o->fd);
}
if(*fd>=0) {
o->fd= -1;
return(1);
}
return(-1);
}