ref: e6b74650876a904bfef14c952fe9411773b2c289
dir: /tools/skeleton.c/
/*
* skeleton.c
* author: Tahseen Mohammad
*/
/* This file depends on WORDS_BIGENDIAN being defined to 1 if the host
* processor stores words with the most significant byte first (like Motorola
* and SPARC, unlike Intel and VAX).
* On little endian systems, WORDS_BIGENDIAN should be undefined.
*
* When using GNU Autotools, the correct value will be written into config.h
* if the autoconf macro AC_C_BIGENDIAN is called in configure.ac.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <ogg/ogg.h>
#include "skeleton.h"
#ifdef WIN32
#define snprintf _snprintf
#endif
static unsigned short
_le_16 (unsigned short s)
{
unsigned short ret=s;
#ifdef WORDS_BIGENDIAN
ret = (s>>8) & 0x00ffU;
ret += (s<<8) & 0xff00U;
#endif
return ret;
}
static ogg_uint32_t
_le_32 (ogg_uint32_t i)
{
ogg_uint32_t ret=i;
#ifdef WORDS_BIGENDIAN
ret = (i>>24);
ret += (i>>8) & 0x0000ff00;
ret += (i<<8) & 0x00ff0000;
ret += (i<<24);
#endif
return ret;
}
static ogg_int64_t
_le_64 (ogg_int64_t l)
{
ogg_int64_t ret=l;
unsigned char *ucptr = (unsigned char *)&ret;
#ifdef WORDS_BIGENDIAN
unsigned char temp;
temp = ucptr [0] ;
ucptr [0] = ucptr [7] ;
ucptr [7] = temp ;
temp = ucptr [1] ;
ucptr [1] = ucptr [6] ;
ucptr [6] = temp ;
temp = ucptr [2] ;
ucptr [2] = ucptr [5] ;
ucptr [5] = temp ;
temp = ucptr [3] ;
ucptr [3] = ucptr [4] ;
ucptr [4] = temp ;
#endif
return (*(ogg_int64_t *)ucptr);
}
/* write an ogg_page to a file pointer */
int write_ogg_page_to_file(ogg_page *og, FILE *out) {
int written;
written = fwrite(og->header,1, og->header_len, out);
written += fwrite(og->body,1, og->body_len, out);
return written;
}
int add_message_header_field(fisbone_packet *fp,
char *header_key,
char *header_value) {
/* size of both key and value + ': ' + CRLF */
int this_message_size = strlen(header_key) + strlen(header_value) + 4;
if (fp->message_header_fields == NULL) {
fp->message_header_fields = _ogg_calloc(this_message_size+1, sizeof(char));
} else {
int new_size = (fp->current_header_size + this_message_size+1) * sizeof(char);
fp->message_header_fields = _ogg_realloc(fp->message_header_fields, new_size);
}
snprintf(fp->message_header_fields + fp->current_header_size,
this_message_size+1,
"%s: %s\r\n",
header_key,
header_value);
fp->current_header_size += this_message_size;
return 0;
}
/* create a ogg_packet from a fishead_packet structure */
ogg_packet ogg_from_fishead(fishead_packet *fp) {
ogg_packet op;
memset(&op, 0, sizeof(op));
op.packet = _ogg_calloc(FISHEAD_SIZE, sizeof(unsigned char));
memset(op.packet, 0, FISHEAD_SIZE);
memcpy (op.packet, FISHEAD_IDENTIFIER, 8); /* identifier */
*((ogg_uint16_t*)(op.packet+8)) = _le_16 (SKELETON_VERSION_MAJOR); /* version major */
*((ogg_uint16_t*)(op.packet+10)) = _le_16 (SKELETON_VERSION_MINOR); /* version minor */
*((ogg_int64_t*)(op.packet+12)) = _le_64 (fp->ptime_n); /* presentationtime numerator */
*((ogg_int64_t*)(op.packet+20)) = _le_64 (fp->ptime_d); /* presentationtime denominator */
*((ogg_int64_t*)(op.packet+28)) = _le_64 (fp->btime_n); /* basetime numerator */
*((ogg_int64_t*)(op.packet+36)) = _le_64 (fp->btime_d); /* basetime denominator */
/* TODO: UTC time, set to zero for now */
op.b_o_s = 1; /* its the first packet of the stream */
op.e_o_s = 0; /* its not the last packet of the stream */
op.bytes = FISHEAD_SIZE; /* length of the packet in bytes */
return op;
}
/* create a ogg_packet from a fisbone_packet structure.
* call this method after the fisbone_packet is filled and all message header fields are added
* by calling add_message_header_field method.
*/
ogg_packet ogg_from_fisbone(fisbone_packet *fp) {
ogg_packet op;
int packet_size = FISBONE_SIZE + fp->current_header_size;
memset (&op, 0, sizeof (op));
op.packet = _ogg_calloc (packet_size, sizeof(unsigned char));
memset (op.packet, 0, packet_size);
memcpy (op.packet, FISBONE_IDENTIFIER, 8); /* identifier */
*((ogg_uint32_t*)(op.packet+8)) = _le_32 (FISBONE_MESSAGE_HEADER_OFFSET); /* offset of the message header fields */
*((ogg_uint32_t*)(op.packet+12)) = _le_32 (fp->serial_no); /* serialno of the respective stream */
*((ogg_uint32_t*)(op.packet+16)) = _le_32 (fp->nr_header_packet); /* number of header packets */
*((ogg_int64_t*)(op.packet+20)) = _le_64 (fp->granule_rate_n); /* granulrate numerator */
*((ogg_int64_t*)(op.packet+28)) = _le_64 (fp->granule_rate_d); /* granulrate denominator */
*((ogg_int64_t*)(op.packet+36)) = _le_64 (fp->start_granule); /* start granule */
*((ogg_uint32_t*)(op.packet+44)) = _le_32 (fp->preroll); /* preroll, for theora its 0 */
*(op.packet+48) = fp->granule_shift; /* granule shift */
memcpy((op.packet+FISBONE_SIZE), fp->message_header_fields, fp->current_header_size);
op.b_o_s = 0;
op.e_o_s = 0;
op.bytes = packet_size; /* size of the packet in bytes */
return op;
}
/* fills up a fishead_packet from a fishead ogg_packet of a skeleton bistream */
fishead_packet fishead_from_ogg(ogg_packet *op) {
fishead_packet fp;
if (memcmp(op->packet, FISHEAD_IDENTIFIER, 8))
; /* invalid packet what do we do? */
fp.version_major = _le_16 (*((ogg_uint16_t*)(op->packet+8))); /* version major */
fp.version_minor = _le_16 (*((ogg_uint16_t*)(op->packet+10))); /* version minor */
fp.ptime_n = _le_64 (*((ogg_int64_t*)(op->packet+12))); /* presentationtime numerator */
fp.ptime_d = _le_64 (*((ogg_int64_t*)(op->packet+20))); /* presentationtime denominator */
fp.btime_n = _le_64 (*((ogg_int64_t*)(op->packet+28))); /* basetime numerator */
fp.btime_d = _le_64 (*((ogg_int64_t*)(op->packet+36))); /* basetime denominator */
memcpy(fp.UTC, op->packet+44, 20);
return fp;
}
/* fills up a fisbone_packet from a fisbone ogg_packet of a skeleton bitstream */
fisbone_packet fisbone_from_ogg(ogg_packet *op) {
fisbone_packet fp;
if (memcmp(op->packet, FISBONE_IDENTIFIER, 8))
; /* invalid value, what do we do? */
fp.serial_no = _le_32 (*((ogg_uint32_t*)(op->packet+12))); /* serialno of the stream represented by this fisbone packet */
fp.nr_header_packet = _le_32 (*((ogg_uint32_t*)(op->packet+16))); /* number of header packets */
fp.granule_rate_n = _le_64 (*((ogg_int64_t*)(op->packet+20))); /* granulrate numerator */
fp.granule_rate_d = _le_64 (*((ogg_int64_t*)(op->packet+28))); /* granulrate denominator */
fp.start_granule = _le_64 (*((ogg_int64_t*)(op->packet+36))); /* start granule */
fp.preroll = _le_32 (*((ogg_uint32_t*)(op->packet+44))); /* preroll, for theora its 0 */
fp.granule_shift = *(op->packet+48); /* granule shift */
fp.current_header_size = op->bytes - FISBONE_SIZE;
fp.message_header_fields = _ogg_calloc(fp.current_header_size+1, sizeof(char));
memcpy(fp.message_header_fields, op->packet+FISBONE_SIZE, fp.current_header_size);
return fp;
}
int add_fishead_to_stream(ogg_stream_state *os, fishead_packet *fp) {
ogg_packet op;
op = ogg_from_fishead(fp);
ogg_stream_packetin(os, &op);
_ogg_free(op.packet);
return 0;
}
int add_fisbone_to_stream(ogg_stream_state *os, fisbone_packet *fp) {
ogg_packet op;
op = ogg_from_fisbone(fp);
ogg_stream_packetin(os, &op);
_ogg_free(op.packet);
return 0;
}
int add_eos_packet_to_stream(ogg_stream_state *os) {
ogg_packet op;
memset (&op, 0, sizeof(op));
op.e_o_s = 1;
ogg_stream_packetin(os, &op);
return 0;
}
int flush_ogg_stream_to_file(ogg_stream_state *os, FILE *out) {
ogg_page og;
int result;
while((result = ogg_stream_flush(os, &og)))
{
if(!result) break;
result = write_ogg_page_to_file(&og, out);
if(result != og.header_len + og.body_len)
return 1;
}
return 0;
}