/*
$Id: read.c,v 1.10 2005/11/10 00:44:41 rocky Exp $
Copyright (C) 2005 Rocky Bernstein <rocky@panix.com>
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
*/
/** \file read.h
*
* \brief sector (block, frame)-related libcdio routines.
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <cdio/cdio.h>
#include <cdio/logging.h>
#include "cdio_private.h"
#include "cdio_assert.h"
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#define check_read_parms(p_cdio, p_buf, i_lsn) \
if (!p_cdio) return DRIVER_OP_UNINIT; \
if (!p_buf || CDIO_INVALID_LSN == i_lsn) \
return DRIVER_OP_ERROR;
#define check_lsn(i_lsn) \
check_read_parms(p_cdio, p_buf, i_lsn); \
{ \
lsn_t end_lsn = \
cdio_get_track_lsn(p_cdio, CDIO_CDROM_LEADOUT_TRACK); \
if ( i_lsn > end_lsn ) { \
cdio_info("Trying to access past end of disk lsn: %ld, end lsn: %ld", \
(long int) i_lsn, (long int) end_lsn); \
return DRIVER_OP_ERROR; \
} \
}
#define check_lsn_blocks(i_lsn, i_blocks) \
check_read_parms(p_cdio, p_buf, i_lsn); \
{ \
lsn_t end_lsn = \
cdio_get_track_lsn(p_cdio, CDIO_CDROM_LEADOUT_TRACK); \
if ( i_lsn > end_lsn ) { \
cdio_info("Trying to access past end of disk lsn: %ld, end lsn: %ld", \
(long int) i_lsn, (long int) end_lsn); \
return DRIVER_OP_ERROR; \
} \
/* Care is used in the expression below to be correct with */ \
/* respect to unsigned integers. */ \
if ( i_lsn + i_blocks > end_lsn + 1 ) { \
cdio_info("Request truncated to end disk; lsn: %ld, end lsn: %ld", \
(long int) i_lsn, (long int) end_lsn); \
i_blocks = end_lsn - i_lsn + 1; \
} \
}
/*!
lseek - reposition read/write file offset
Returns (off_t) -1 on error.
Similar to (if not the same as) libc's lseek()
*/
off_t
cdio_lseek (const CdIo_t *p_cdio, off_t offset, int whence)
{
if (!p_cdio) return DRIVER_OP_UNINIT;
if (p_cdio->op.lseek)
return (p_cdio->op.lseek) (p_cdio->env, offset, whence);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads into buf the next size bytes.
Returns -1 on error.
Similar to (if not the same as) libc's read()
*/
ssize_t
cdio_read (const CdIo_t *p_cdio, void *p_buf, size_t i_size)
{
if (!p_cdio) return DRIVER_OP_UNINIT;
if (p_cdio->op.read)
return (p_cdio->op.read) (p_cdio->env, p_buf, i_size);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads an audio sector from cd device into data starting
from lsn. Returns DRIVER_OP_SUCCESS if no error.
*/
driver_return_code_t
cdio_read_audio_sector (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn)
{
check_lsn(i_lsn);
if (p_cdio->op.read_audio_sectors)
return p_cdio->op.read_audio_sectors (p_cdio->env, p_buf, i_lsn, 1);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads audio sectors from cd device into data starting
from lsn. Returns DRIVER_OP_SUCCESS if no error.
*/
driver_return_code_t
cdio_read_audio_sectors (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
uint32_t i_blocks)
{
check_lsn_blocks(i_lsn, i_blocks);
if (0 == i_blocks) return DRIVER_OP_SUCCESS;
if (p_cdio->op.read_audio_sectors)
return (p_cdio->op.read_audio_sectors) (p_cdio->env, p_buf, i_lsn,
i_blocks);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads an audio sector from cd device into data starting
from lsn. Returns DRIVER_OP_SUCCESS if no error.
*/
driver_return_code_t
cdio_read_data_sectors (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
uint16_t i_blocksize, uint32_t i_blocks)
{
check_lsn(i_lsn);
if (0 == i_blocks) return DRIVER_OP_SUCCESS;
if (p_cdio->op.read_data_sectors)
return p_cdio->op.read_data_sectors (p_cdio->env, p_buf, i_lsn,
i_blocksize, i_blocks);
return DRIVER_OP_UNSUPPORTED;
}
#ifndef SEEK_SET
#define SEEK_SET 0
#endif
/*!
Reads a single mode1 form1 or form2 sector from cd device
into data starting from lsn. Returns DRIVER_OP_SUCCESS if no error.
*/
driver_return_code_t
cdio_read_mode1_sector (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
bool b_form2)
{
uint32_t size = b_form2 ? M2RAW_SECTOR_SIZE : CDIO_CD_FRAMESIZE ;
check_lsn(i_lsn);
if (p_cdio->op.read_mode1_sector) {
return p_cdio->op.read_mode1_sector(p_cdio->env, p_buf, i_lsn, b_form2);
} else if (p_cdio->op.lseek && p_cdio->op.read) {
char buf[CDIO_CD_FRAMESIZE] = { 0, };
if (0 > cdio_lseek(p_cdio, CDIO_CD_FRAMESIZE*i_lsn, SEEK_SET))
return -1;
if (0 > cdio_read(p_cdio, buf, CDIO_CD_FRAMESIZE))
return -1;
memcpy (p_buf, buf, size);
return DRIVER_OP_SUCCESS;
}
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads mode 1 sectors
@param p_cdio object to read from
@param buf place to read data into
@param lsn sector to read
@param b_form2 true for reading mode 1 form 2 sectors or false for
mode 1 form 1 sectors.
@param i_blocks number of sectors to read
*/
driver_return_code_t
cdio_read_mode1_sectors (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
bool b_form2, uint32_t i_blocks)
{
check_lsn_blocks(i_lsn, i_blocks);
if (0 == i_blocks) return DRIVER_OP_SUCCESS;
if (p_cdio->op.read_mode1_sectors)
return (p_cdio->op.read_mode1_sectors) (p_cdio->env, p_buf, i_lsn, b_form2,
i_blocks);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads a mode 2 sector
@param p_cdio object to read from
@param buf place to read data into
@param lsn sector to read
@param b_form2 true for reading mode 2 form 2 sectors or false for
mode 2 form 1 sectors.
*/
driver_return_code_t
cdio_read_mode2_sector (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
bool b_form2)
{
check_lsn(i_lsn);
if (p_cdio->op.read_mode2_sector)
return p_cdio->op.read_mode2_sector (p_cdio->env, p_buf, i_lsn, b_form2);
/* fallback */
if (p_cdio->op.read_mode2_sectors != NULL)
return cdio_read_mode2_sectors (p_cdio, p_buf, i_lsn, b_form2, 1);
return DRIVER_OP_UNSUPPORTED;
}
/*!
Reads mode 2 sectors
@param p_cdio object to read from
@param buf place to read data into
@param lsn sector to read
@param b_form2 true for reading mode2 form 2 sectors or false for
mode 2 form 1 sectors.
@param i_blocks number of sectors to read
*/
driver_return_code_t
cdio_read_mode2_sectors (const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
bool b_form2, uint32_t i_blocks)
{
check_lsn_blocks(i_lsn, i_blocks);
if (0 == i_blocks) return DRIVER_OP_SUCCESS;
if (p_cdio->op.read_mode2_sectors)
return (p_cdio->op.read_mode2_sectors) (p_cdio->env, p_buf, i_lsn,
b_form2, i_blocks);
return DRIVER_OP_UNSUPPORTED;
}
/** The special case of reading a single block is a common one so we
provide a routine for that as a convenience.
*/
driver_return_code_t
cdio_read_sector(const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
cdio_read_mode_t read_mode)
{
return cdio_read_sectors(p_cdio, p_buf, i_lsn, read_mode, 1);
}
/*!
Reads a number of sectors (AKA blocks).
@param p_buf place to read data into. The caller should make sure
this location is large enough. See below for size information.
@param read_mode the kind of "mode" to use in reading.
@param i_lsn sector to read
@param i_blocks number of sectors to read
@return DRIVER_OP_SUCCESS (0) if no error, other (negative) enumerations
are returned on error.
If read_mode is CDIO_MODE_AUDIO,
*p_buf should hold at least CDIO_FRAMESIZE_RAW * i_blocks bytes.
If read_mode is CDIO_MODE_DATA,
*p_buf should hold at least i_blocks times either ISO_BLOCKSIZE,
M1RAW_SECTOR_SIZE or M2F2_SECTOR_SIZE depending on the kind of
sector getting read. If you don't know whether you have a Mode 1/2,
Form 1/ Form 2/Formless sector best to reserve space for the maximum
which is M2RAW_SECTOR_SIZE.
If read_mode is CDIO_MODE_M2F1,
*p_buf should hold at least M2RAW_SECTOR_SIZE * i_blocks bytes.
If read_mode is CDIO_MODE_M2F2,
*p_buf should hold at least CDIO_CD_FRAMESIZE * i_blocks bytes.
*/
driver_return_code_t
cdio_read_sectors(const CdIo_t *p_cdio, void *p_buf, lsn_t i_lsn,
cdio_read_mode_t read_mode, uint32_t i_blocks)
{
switch(read_mode) {
case CDIO_READ_MODE_AUDIO:
return cdio_read_audio_sectors (p_cdio, p_buf, i_lsn, i_blocks);
case CDIO_READ_MODE_M1F1:
return cdio_read_mode1_sectors (p_cdio, p_buf, i_lsn, false, i_blocks);
case CDIO_READ_MODE_M1F2:
return cdio_read_mode1_sectors (p_cdio, p_buf, i_lsn, true, i_blocks);
case CDIO_READ_MODE_M2F1:
return cdio_read_mode2_sectors (p_cdio, p_buf, i_lsn, false, i_blocks);
case CDIO_READ_MODE_M2F2:
return cdio_read_mode2_sectors (p_cdio, p_buf, i_lsn, true, i_blocks);
}
/* Can't happen. Just to shut up gcc. */
return DRIVER_OP_ERROR;
}
/*
* Local variables:
* c-file-style: "gnu"
* tab-width: 8
* indent-tabs-mode: nil
* End:
*/
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