openjpeg/applications/jpip/tools/indexer/jpip.c

779 lines
22 KiB
C

/*
* Copyright (c) 2003-2004, Yannick Verschueren
* Copyright (c) 2003-2004, Communications and remote sensing Laboratory, Universite catholique de Louvain, Belgium
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
#include <math.h>
#include <unistd.h>
#include "j2k.h"
#include "cio.h"
#include "tcd.h"
#include "int.h"
#define JPIP_CIDX 0x63696478 /* Codestream index */
#define JPIP_CPTR 0x63707472 /* Codestream Finder Box */
#define JPIP_MANF 0x6d616e66 /* Manifest Box */
#define JPIP_FAIX 0x66616978 /* Fragment array Index box */
#define JPIP_MHIX 0x6d686978 /* Main Header Index Table */
#define JPIP_TPIX 0x74706978 /* Tile-part Index Table box */
#define JPIP_THIX 0x74686978 /* Tile header Index Table box */
#define JPIP_PPIX 0x70706978 /* Precinct Packet Index Table box */
#define JPIP_PHIX 0x70686978 /* Packet Header index Table */
#define JPIP_FIDX 0x66696478 /* File Index */
#define JPIP_FPTR 0x66707472 /* File Finder */
#define JPIP_PRXY 0x70727879 /* Proxy boxes */
#define JPIP_IPTR 0x69707472 /* Index finder box */
#define JPIP_PHLD 0x70686c64 /* Place holder */
#define JP2C 0x6a703263
//static info_marker_t marker_jpip[32], marker_local_jpip[32]; /* SIZE to precise ! */
//static int num_marker_jpip, num_marker_local_jpip;
/*
* Write the CPTR box
*
* Codestream finder box (box)
*
*/
void jpip_write_cptr(int offset, info_image_t img)
{
int len, lenp;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_CPTR,4); /* T */
cio_write(0,2); /* DR A PRECISER !! */
cio_write(0,2); /* CONT */
cio_write(offset,8); /* COFF A PRECISER !! */
cio_write(img.codestream_size,8); /* CLEN */
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
/*
* Read the CPTR box
*
* Codestream finder box (box)
*
*/
void jpip_read_cptr()
{
int DR, CONT;
long long Coff, codestream_size;
DR = cio_read(2); /* DR */
CONT = cio_read(2); /* CONT */
Coff = cio_read(8); /* COFF */
codestream_size = cio_read(8); /* CLEN */
}
/*
* Write the MANF box
*
* Manifest box (box)
*
*/
void jpip_write_manf(int second, int v, info_marker_t *marker)
{
int len, lenp, i;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_MANF,4); /* T */
if (second) /* Write only during the second pass */
{
for(i=0;i<v;i++)
{
cio_write(marker[i].len,4); /* Marker length */
cio_write(marker[i].type,4); /* Marker type */
}
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
/*
* Read the MANF box
*
* Manifest box (box)
*
*/
void jpip_read_manf(int len)
{
int i, v, marker_len, marker_type;
v = (len - 8)/ 8;
for(i=0;i<v;i++)
{
marker_len = cio_read(4); /* Marker length */
marker_type = cio_read(4); /* Marker type */
}
}
/*
* Write the MHIX box
*
* Main Header Index Table (box)
*
*/
int jpip_write_mhix(info_image_t img, int status, int tileno)
{
int len, lenp, i;
info_tile_t *tile;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_MHIX, 4); /* MHIX */
if (status==0) /* MAIN HEADER */
{
cio_write(img.Main_head_end,8); /* TLEN */
for(i = 0; i < img.num_marker; i++) /* Marker restricted to 1 apparition */
{
cio_write(img.marker[i].type, 2);
cio_write(0, 2);
cio_write(img.marker[i].start_pos, 8);
cio_write(img.marker[i].len, 2);
}
/* Marker NOT restricted to 1 apparition */
for(i = img.marker_mul.num_COC - 1; i >= 0; i--) /* COC */
{
cio_write(img.marker_mul.COC[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.COC[i].start_pos, 8);
cio_write(img.marker_mul.COC[i].len, 2);
}
for(i = img.marker_mul.num_RGN - 1; i >= 0; i--) /* RGN */
{
cio_write(img.marker_mul.RGN[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.RGN[i].start_pos, 8);
cio_write(img.marker_mul.RGN[i].len, 2);
}
for(i = img.marker_mul.num_QCC - 1; i >= 0; i--) /* QCC */
{
cio_write(img.marker_mul.QCC[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.QCC[i].start_pos, 8);
cio_write(img.marker_mul.QCC[i].len, 2);
}
for(i = img.marker_mul.num_TLM - 1; i >= 0; i--) /* TLM */
{
cio_write(img.marker_mul.TLM[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.TLM[i].start_pos, 8);
cio_write(img.marker_mul.TLM[i].len, 2);
}
for(i = img.marker_mul.num_PLM - 1; i >= 0; i--) /* PLM */
{
cio_write(img.marker_mul.PLM[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.PLM[i].start_pos, 8);
cio_write(img.marker_mul.PLM[i].len, 2);
}
for(i = img.marker_mul.num_PPM - 1; i >= 0; i--) /* PPM */
{
cio_write(img.marker_mul.PPM[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.PPM[i].start_pos, 8);
cio_write(img.marker_mul.PPM[i].len, 2);
}
for(i = img.marker_mul.num_COM - 1; i >= 0; i--) /* COM */
{
cio_write(img.marker_mul.COM[i].type, 2);
cio_write(i, 2);
cio_write(img.marker_mul.COM[i].start_pos, 8);
cio_write(img.marker_mul.COM[i].len, 2);
}
}
else /* TILE HEADER */
{
tile = &img.tile[tileno];
cio_write(tile->tile_parts[0].length_header, 8); /* TLEN */
for(i = 0; i < tile->num_marker; i++) /* Marker restricted to 1 apparition */
{
cio_write(tile->marker[i].type, 2);
cio_write(0, 2);
cio_write(tile->marker[i].start_pos, 8);
cio_write(tile->marker[i].len, 2);
}
/* Marker NOT restricted to 1 apparition */
for(i = tile->marker_mul.num_COC - 1; i >= 0; i--) /* COC */
{
cio_write(tile->marker_mul.COC[i].type, 2);
cio_write(i, 2);
cio_write(tile->marker_mul.COC[i].start_pos, 8);
cio_write(tile->marker_mul.COC[i].len, 2);
}
for(i = tile->marker_mul.num_RGN - 1; i >= 0; i--) /* RGN */
{
cio_write(tile->marker_mul.RGN[i].type, 2);
cio_write(i, 2);
cio_write(tile->marker_mul.RGN[i].start_pos, 8);
cio_write(tile->marker_mul.RGN[i].len, 2);
}
for(i = tile->marker_mul.num_QCC - 1; i >= 0; i--) /* QCC */
{
cio_write(tile->marker_mul.QCC[i].type, 2);
cio_write(i, 2);
cio_write(tile->marker_mul.QCC[i].start_pos, 8);
cio_write(tile->marker_mul.QCC[i].len, 2);
}
for(i = tile->marker_mul.num_PLT - 1; i >= 0; i--) /* PLT */
{
cio_write(tile->marker_mul.PLT[i].type,2);
cio_write(i,2);
cio_write(tile->marker_mul.PLT[i].start_pos,8);
cio_write(tile->marker_mul.PLT[i].len,2);
}
for(i = tile->marker_mul.num_PPT - 1; i >= 0; i--) /* PPT */
{
cio_write(tile->marker_mul.PPT[i].type, 2);
cio_write(i, 2);
cio_write(tile->marker_mul.PPT[i].start_pos, 8);
cio_write(tile->marker_mul.PPT[i].len, 2);
}
for(i = tile->marker_mul.num_COM - 1; i >= 0; i--) /* COM */
{
cio_write(tile->marker_mul.COM[i].type, 2);
cio_write(i, 2);
cio_write(tile->marker_mul.COM[i].start_pos, 8);
cio_write(tile->marker_mul.COM[i].len, 2);
}
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
return len;
}
/*
* Read the MHIX box
*
* Main Header Index Table (box)
*
*/
void jpip_read_mhix(int len)
{
int i, v, marker_type, marker_start_pos, marker_len, marker_remains;
v = (len - 8) / 14;
for (i=0; i<v ; i++)
{
marker_type = cio_read(2); /* Type of the marker */
marker_remains = cio_read(2); /* Number of same markers following */
marker_start_pos = cio_read(2); /* Start position of the marker */
marker_len = cio_read(2); /* Length of the marker */
}
}
/*
* Write the FAIX box
*
* Fragment array Index box (box)
*
*/
int jpip_write_faix(int v, int compno, info_image_t img, j2k_cp_t *j2k_cp, int version)
{
int len, lenp, i, j;
int Aux;
int tileno, resno, precno, layno, num_packet=0;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_FAIX, 4); /* FAIX */
cio_write(version,1); /* Version 0 = 4 bytes */
switch(v)
{
case 0: /* TPIX */
cio_write(img.num_max_tile_parts,(version & 0x01)?8:4); /* NMAX */
cio_write(img.tw*img.th,(version & 0x01)?8:4); /* M */
for (i = 0; i < img.tw*img.th; i++)
{
for (j = 0; j < img.tile[i].numparts ; j++)
{
cio_write(img.tile[i].tile_parts[j].start_pos,(version & 0x01)?8:4); /* start position */
cio_write(img.tile[i].tile_parts[j].length,(version & 0x01)?8:4); /* length */
if (version & 0x02)
{
if (img.tile[i].numparts == 1 && img.Decomposition > 1)
Aux = img.Decomposition + 1;
else
Aux = j + 1;
cio_write(Aux,4);
//cio_write(img.tile[i].tile_parts[j].num_reso_AUX,4); /* Aux_i,j : Auxiliary value */
// fprintf(stderr,"AUX value %d\n",Aux);
}
//cio_write(0,4);
}
/* PADDING */
while (j < img.num_max_tile_parts)
{
cio_write(0,(version & 0x01)?8:4); /* start position */
cio_write(0,(version & 0x01)?8:4); /* length */
if (version & 0x02)
cio_write(0,4); /* Aux_i,j : Auxiliary value */
j++;
}
}
break;
/* case 1: */ /* THIX */
/* cio_write(1,(version & 0x01)?8:4); */ /* NMAX */
/* cio_write(img.tw*img.th,(version & 0x01)?8:4); */ /* M */
/* for (i=0;i<img.tw*img.th;i++) */
/* { */
/* cio_write(img.tile[i].start_pos,(version & 0x01)?8:4); */ /* start position */
/* cio_write(img.tile[i].end_header-img.tile[i].start_pos,(version & 0x01)?8:4); */ /* length */
/* if (version & 0x02)*/
/* cio_write(0,4); */ /* Aux_i,j : Auxiliary value */
/* } */
/* break; */
case 2: /* PPIX NOT FINISHED !! */
cio_write(img.num_packet_max,(version & 0x01)?8:4); /* NMAX */
cio_write(img.tw*img.th,(version & 0x01)?8:4); /* M */
for(tileno=0;tileno<img.tw*img.th;tileno++)
{
info_tile_t *tile_Idx = &img.tile[tileno];
info_compo_t *compo_Idx = &tile_Idx->compo[compno];
int correction;
num_packet=0;
if(j2k_cp->tcps[tileno].csty&J2K_CP_CSTY_EPH)
correction=3;
else
correction=1;
for(resno=0;resno<img.Decomposition+1;resno++)
{
info_reso_t *reso_Idx = &compo_Idx->reso[resno];
for (precno=0;precno<img.tile[tileno].pw*img.tile[tileno].ph;precno++)
{
info_prec_t *prec_Idx = &reso_Idx->prec[precno];
for(layno=0;layno<img.Layer;layno++)
{
info_layer_t *layer_Idx = &prec_Idx->layer[layno];
cio_write(layer_Idx->offset,(version & 0x01)?8:4); /* start position */
cio_write((layer_Idx->len_header-correction)?0:layer_Idx->len,(version & 0x01)?8:4); /* length */
if (version & 0x02)
cio_write(0,4); /* Aux_i,j : Auxiliary value */
num_packet++;
}
}
}
/* PADDING */
while (num_packet < img.num_packet_max)
{
cio_write(0,(version & 0x01)?8:4); /* start position */
cio_write(0,(version & 0x01)?8:4); /* length */
if (version & 0x02)
cio_write(0,4); /* Aux_i,j : Auxiliary value */
num_packet++;
}
}
break;
case 3: /* PHIX NOT FINISHED !! */
cio_write(img.num_packet_max,(version & 0x01)?8:4); /* NMAX */
cio_write(img.tw*img.th,(version & 0x01)?8:4); /* M */
for(tileno=0;tileno<img.tw*img.th;tileno++)
{
info_tile_t *tile_Idx = &img.tile[tileno];
info_compo_t *compo_Idx = &tile_Idx->compo[compno];
int correction;
num_packet = 0;
if(j2k_cp->tcps[tileno].csty&J2K_CP_CSTY_EPH)
correction=3;
else
correction=1;
for(resno=0;resno<img.Decomposition+1;resno++)
{
info_reso_t *reso_Idx = &compo_Idx->reso[resno];
for (precno=0;precno<img.tile[tileno].pw*img.tile[tileno].ph;precno++)
{
info_prec_t *prec_Idx = &reso_Idx->prec[precno];
for(layno=0;layno<img.Layer;layno++)
{
info_layer_t *layer_Idx = &prec_Idx->layer[layno];
cio_write(layer_Idx->offset_header,(version & 0x01)?8:4); /* start position */
cio_write((layer_Idx->len_header-correction)?0:layer_Idx->len_header,(version & 0x01)?8:4); /* length */
if (version & 0x02)
cio_write(0,4); /* Aux_i,j : Auxiliary value */
num_packet++;
}
}
}
/* PADDING */
while (num_packet<img.num_packet_max)
{
cio_write(0,(version & 0x01)?8:4); /* start position */
cio_write(0,(version & 0x01)?8:4); /* length */
if (version & 0x02)
cio_write(0,4); /* Aux_i,j : Auxiliary value */
num_packet++;
}
}
break;
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
return len;
}
/*
* Write the TPIX box
*
* Tile-part Index table box (superbox)
*
*/
int jpip_write_tpix(info_image_t img, j2k_cp_t *j2k_cp, int version)
{
int len, lenp;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_TPIX, 4); /* TPIX */
jpip_write_faix(0,0,img, j2k_cp, version);
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
return len;
}
/*
* Write the THIX box
*
* Tile header Index table box (superbox)
*
*/
//int jpip_write_thix(info_image_t img, j2k_cp_t *j2k_cp)
// {
// int len, lenp;
// lenp=cio_tell();
// cio_skip(4); /* L [at the end] */
// cio_write(JPIP_THIX, 4); /* THIX */
// jpip_write_faix(1,0,img, j2k_cp);
// len=cio_tell()-lenp;
// cio_seek(lenp);
// cio_write(len, 4); /* L */
// cio_seek(lenp+len);
// return len;
//}
int jpip_write_thix(info_image_t img, j2k_cp_t *j2k_cp)
{
int len, lenp, i;
int tileno;
info_marker_t *marker;
int num_marker_local_jpip;
marker = (info_marker_t*)calloc(sizeof(info_marker_t), j2k_cp->tw*j2k_cp->th);
for ( i = 0; i < 2 ; i++ )
{
if (i) cio_seek(lenp);
lenp = cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_THIX, 4); /* THIX */
jpip_write_manf(i, j2k_cp->tw*j2k_cp->th, marker);
num_marker_local_jpip=img.Comp;
for (tileno = 0; tileno < j2k_cp->tw*j2k_cp->th; tileno++)
{
marker[tileno].len = jpip_write_mhix(img, 1, tileno);
marker[tileno].type = JPIP_MHIX;
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
free(marker);
return len;
}
/*
* Write the PPIX box
*
* Precinct Packet Index table box (superbox)
*
*/
int jpip_write_ppix(info_image_t img,j2k_cp_t *j2k_cp)
{
int len, lenp, compno, i;
info_marker_t *marker;
int num_marker_local_jpip;
marker = (info_marker_t*)calloc(sizeof(info_marker_t), img.Comp);
for (i=0;i<2;i++)
{
if (i) cio_seek(lenp);
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_PPIX, 4); /* PPIX */
jpip_write_manf(i,img.Comp,marker);
num_marker_local_jpip=img.Comp;
for (compno=0; compno<img.Comp; compno++)
{
marker[compno].len=jpip_write_faix(2,compno,img, j2k_cp, 0);
marker[compno].type=JPIP_FAIX;
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
free(marker);
return len;
}
/*
* Write the PHIX box
*
* Packet Header Index table box (superbox)
*
*/
int jpip_write_phix(info_image_t img, j2k_cp_t *j2k_cp)
{
int len, lenp=0, compno, i;
info_marker_t *marker;
marker = (info_marker_t*)calloc(sizeof(info_marker_t), img.Comp);
for (i=0;i<2;i++)
{
if (i) cio_seek(lenp);
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_PHIX, 4); /* PHIX */
jpip_write_manf(i,img.Comp,marker);
for (compno=0; compno<img.Comp; compno++)
{
marker[compno].len=jpip_write_faix(3,compno,img, j2k_cp, 0);
marker[compno].type=JPIP_FAIX;
}
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
free(marker);
return len;
}
/*
* Write the CIDX box
*
* Codestream Index box (superbox)
*
*/
int jpip_write_cidx(int offset, info_image_t img, j2k_cp_t *j2k_cp, int version)
{
int len, lenp = 0, i;
info_marker_t *marker_jpip;
int num_marker_jpip = 0;
marker_jpip = (info_marker_t*)calloc(sizeof(info_marker_t), 32);
for (i=0;i<2;i++)
{
if(i)
cio_seek(lenp);
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_CIDX, 4); /* CIDX */
jpip_write_cptr(offset, img);
jpip_write_manf(i,num_marker_jpip, marker_jpip);
num_marker_jpip=0;
marker_jpip[num_marker_jpip].len=jpip_write_mhix(img, 0, 0);
marker_jpip[num_marker_jpip].type=JPIP_MHIX;
num_marker_jpip++;
marker_jpip[num_marker_jpip].len=jpip_write_tpix(img, j2k_cp, version);
marker_jpip[num_marker_jpip].type=JPIP_TPIX;
num_marker_jpip++;
marker_jpip[num_marker_jpip].len=jpip_write_thix(img, j2k_cp);
marker_jpip[num_marker_jpip].type=JPIP_THIX;
num_marker_jpip++;
marker_jpip[num_marker_jpip].len=jpip_write_ppix(img, j2k_cp);
marker_jpip[num_marker_jpip].type=JPIP_PPIX;
num_marker_jpip++;
marker_jpip[num_marker_jpip].len=jpip_write_phix(img, j2k_cp);
marker_jpip[num_marker_jpip].type=JPIP_PHIX;
num_marker_jpip++;
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
free(marker_jpip);
return len;
}
/*
* Write the IPTR box
*
* Index Finder box
*
*/
void jpip_write_iptr(int offset, int length)
{
int len, lenp;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_IPTR, 4); /* IPTR */
cio_write(offset,8);
cio_write(length,8);
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
/*
* Write the PRXY box
*
* proxy (box)
*
*/
void jpip_write_prxy(int offset_jp2c, int length_jp2c, int offset_idx, int length_idx)
{
int len, lenp;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_PRXY, 4); /* IPTR */
cio_write(offset_jp2c,8); /* OOFF */
cio_write(length_jp2c,4); /* OBH part 1 */
cio_write(JP2C,4); /* OBH part 2 */
cio_write(1,1); /* NI */
cio_write(offset_idx,8); /* IOFF */
cio_write(length_idx,4); /* IBH part 1 */
cio_write(JPIP_CIDX,4); /* IBH part 2 */
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
}
/*
* Write the FIDX box
*
* File Index (superbox)
*
*/
int jpip_write_fidx(int offset_jp2c, int length_jp2c, int offset_idx, int length_idx)
{
int len, lenp;
lenp=cio_tell();
cio_skip(4); /* L [at the end] */
cio_write(JPIP_FIDX, 4); /* IPTR */
jpip_write_prxy(offset_jp2c, length_jp2c, offset_idx, offset_jp2c);
len=cio_tell()-lenp;
cio_seek(lenp);
cio_write(len, 4); /* L */
cio_seek(lenp+len);
return len;
}