lxdream.org :: lxdream/src/gdrom/gdimage.c r640:01b50fd48035

tree revision 640:01b50fd48035

filename	src/gdrom/gdimage.c
changeset	640:01b50fd48035
prev	561:533f6b478071
next	644:ccae4bfa5f82
author	nkeynes
date	Thu Feb 21 06:12:00 2008 +0000 (12 years ago)
permissions	-rw-r--r--
last change	Quick fix to get dclinux.nrg running. Real fix to follow later

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     1 /**

     2  * $Id$

     3  *

     4  * GD-Rom image-file common functions.

     5  *

     6  * Copyright (c) 2005 Nathan Keynes.

     7  *

     8  * This program is free software; you can redistribute it and/or modify

     9  * it under the terms of the GNU General Public License as published by

    10  * the Free Software Foundation; either version 2 of the License, or

    11  * (at your option) any later version.

    12  *

    13  * This program is distributed in the hope that it will be useful,

    14  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    16  * GNU General Public License for more details.

    17  */

    19 #include <netinet/in.h>

    21 #include "gdrom/gdrom.h"

    22 #include "gdrom/packet.h"

    23 #include "bootstrap.h"

    25 static void gdrom_image_destroy( gdrom_disc_t disc );

    26 static gdrom_error_t gdrom_image_read_sector( gdrom_disc_t disc, uint32_t lba, int mode,

    27 					      unsigned char *buf, uint32_t *readlength );

    28 static gdrom_error_t gdrom_image_read_toc( gdrom_disc_t disc, unsigned char *buf );

    29 static gdrom_error_t gdrom_image_read_session( gdrom_disc_t disc, int session, unsigned char *buf );

    30 static gdrom_error_t gdrom_image_read_position( gdrom_disc_t disc, uint32_t lba, unsigned char *buf );

    31 static int gdrom_image_drive_status( gdrom_disc_t disc );

    33 struct cdrom_sector_header {

    34     uint8_t sync[12];

    35     uint8_t msf[3];

    36     uint8_t mode;

    37 };

    39 /**

    40  * Initialize a gdrom_disc structure with the gdrom_image_* methods

    41  */

    42 void gdrom_image_init( gdrom_disc_t disc )

    43 {

    44     memset( disc, 0, sizeof(struct gdrom_disc) ); /* safety */

    45     disc->read_sector = gdrom_image_read_sector;

    46     disc->read_toc = gdrom_image_read_toc;

    47     disc->read_session = gdrom_image_read_session;

    48     disc->read_position = gdrom_image_read_position;

    49     disc->drive_status = gdrom_image_drive_status;

    50     disc->play_audio = NULL; /* not supported yet */

    51     disc->run_time_slice = NULL; /* not needed */

    52     disc->close = gdrom_image_destroy;

    53 }

    55 gdrom_disc_t gdrom_image_new( const gchar *filename, FILE *f )

    56 {

    57     gdrom_image_t image = (gdrom_image_t)calloc(sizeof(struct gdrom_image), 1);

    58     if( image == NULL ) {

    59 	return NULL;

    60     }

    61     image->disc_type = IDE_DISC_CDROM;

    62     image->file = f;

    63     gdrom_disc_t disc = (gdrom_disc_t)image;

    64     gdrom_image_init(disc);

    65     if( filename == NULL ) {

    66 	disc->name = NULL;

    67     } else {

    68 	disc->name = g_strdup(filename);

    69     }

    71     return disc;

    72 }

    74 static void gdrom_image_destroy( gdrom_disc_t disc )

    75 {

    76     int i;

    77     FILE *lastfile = NULL;

    78     gdrom_image_t img = (gdrom_image_t)disc;

    79     if( img->file != NULL ) {

    80 	fclose(img->file);

    81 	img->file = NULL;

    82     }

    83     for( i=0; i<img->track_count; i++ ) {

    84 	if( img->track[i].file != NULL && img->track[i].file != lastfile ) {

    85 	    lastfile = img->track[i].file;

    86 	    fclose(lastfile);

    87 	    img->track[i].file = NULL;

    88 	}

    89     }

    90     if( disc->name != NULL ) {

    91 	g_free( (gpointer)disc->name );

    92 	disc->name = NULL;

    93     }

    94     free( disc );

    95 }

    97 void gdrom_image_destroy_no_close( gdrom_disc_t disc )

    98 {

    99     int i;

   100     FILE *lastfile = NULL;

   101     gdrom_image_t img = (gdrom_image_t)disc;

   102     if( img->file != NULL ) {

   103 	img->file = NULL;

   104     }

   105     for( i=0; i<img->track_count; i++ ) {

   106 	if( img->track[i].file != NULL && img->track[i].file != lastfile ) {

   107 	    lastfile = img->track[i].file;

   108 	    fclose(lastfile);

   109 	    img->track[i].file = NULL;

   110 	}

   111     }

   112     if( disc->name != NULL ) {

   113 	g_free( (gpointer)disc->name );

   114 	disc->name = NULL;

   115     }

   116     free( disc );

   117 }

   119 static int gdrom_image_get_track_by_lba( gdrom_image_t image, uint32_t lba )

   120 {

   121     int i;

   122     for( i=0; i<image->track_count; i++ ) {

   123 	if( image->track[i].lba <= lba &&

   124 	    lba < (image->track[i].lba + image->track[i].sector_count) ) {

   125 	    return i+1;

   126 	}

   127     }

   128     return -1;

   129 }

   131 /**

   132  * Read a block from an image file, handling negative file offsets

   133  * with 0-fill.

   134  */

   135 static void gdrom_read_block( unsigned char *buf, int file_offset, int length, FILE *f )

   136 {

   137     if( file_offset < 0 ) {

   138 	int size = -file_offset;

   139 	if( size >= length ) {

   140 	    memset( buf, 0, length );

   141 	    return;

   142 	} else {

   143 	    memset( buf, 0, size );

   144 	    file_offset = 0;

   145 	    length -= size;

   146 	}

   147     }

   148     fseek( f, file_offset, SEEK_SET );

   149     fread( buf, length, 1, f );

   150 }

   152 static gdrom_error_t gdrom_image_read_sector( gdrom_disc_t disc, uint32_t lba,

   153 					      int mode, unsigned char *buf, uint32_t *length )

   154 {

   155     gdrom_image_t image = (gdrom_image_t)disc;

   156     struct cdrom_sector_header secthead;

   157     int file_offset, read_len, track_no;

   159     FILE *f;

   161     track_no = gdrom_image_get_track_by_lba( image, lba );

   162     if( track_no == -1 ) {

   163 	return PKT_ERR_BADREAD;

   164     }

   165     struct gdrom_track *track = &image->track[track_no-1];

   166     file_offset = track->offset + track->sector_size * (lba - track->lba);

   167     read_len = track->sector_size;

   168     if( track->file != NULL ) {

   169 	f = track->file;

   170     } else {

   171 	f = image->file;

   172     }

   176     switch( mode ) {

   177     case 0x20: /* Actually, read anything, but for now... */

   178     case 0x24:

   179     case 0x28:

   180 	read_len = 2048;

   181 	switch( track->mode ) {

   182 	case GDROM_MODE1:

   183 	case GDROM_MODE2_XA1:

   184 	    gdrom_read_block( buf, file_offset, track->sector_size, f );

   185 	    break;

   186 	case GDROM_MODE2:

   187 	    file_offset += 8; /* skip the subheader */

   188 	    gdrom_read_block( buf, file_offset, 2048, f );

   189 	    break;

   190 	case GDROM_RAW:

   191 	    gdrom_read_block( (unsigned char *)(&secthead), file_offset, sizeof(secthead), f );

   192 	    switch( secthead.mode ) {

   193 	    case 1:

   194 		file_offset += 16;

   195 		break;

   196 	    case 2:

   197 		file_offset += 24;

   198 		break;

   199 	    default:

   200 		return PKT_ERR_BADREADMODE;

   201 	    }

   202 	    gdrom_read_block( buf, file_offset, 2048, f );

   203 	    break;

   204 	default:

   205 	    return PKT_ERR_BADREADMODE;

   206 	}

   207 	break;

   208     default:

   209 	return PKT_ERR_BADREADMODE;

   210     }

   212     *length = read_len;

   213     return PKT_ERR_OK;

   215 }

   217 static gdrom_error_t gdrom_image_read_toc( gdrom_disc_t disc, unsigned char *buf )

   218 {

   219     gdrom_image_t image = (gdrom_image_t)disc;

   220     struct gdrom_toc *toc = (struct gdrom_toc *)buf;

   221     int i;

   223     for( i=0; i<image->track_count; i++ ) {

   224 	toc->track[i] = htonl( image->track[i].lba ) | image->track[i].flags;

   225     }

   226     toc->first = 0x0100 | image->track[0].flags;

   227     toc->last = (image->track_count<<8) | image->track[i-1].flags;

   228     toc->leadout = htonl(image->track[i-1].lba + image->track[i-1].sector_count) |

   229 	image->track[i-1].flags;

   230     for( ;i<99; i++ )

   231 	toc->track[i] = 0xFFFFFFFF;

   232     return PKT_ERR_OK;

   233 }

   235 static gdrom_error_t gdrom_image_read_session( gdrom_disc_t disc, int session, unsigned char *buf )

   236 {

   237     gdrom_image_t image = (gdrom_image_t)disc;

   238     struct gdrom_track *last_track = &image->track[image->track_count-1];

   239     unsigned int end_of_disc = last_track->lba + last_track->sector_count;

   240     int i;

   241     buf[0] = 0x01; /* Disc status? */

   242     buf[1] = 0;

   244     if( session == 0 ) {

   245 	buf[2] = last_track->session+1; /* last session */

   246 	buf[3] = (end_of_disc >> 16) & 0xFF;

   247 	buf[4] = (end_of_disc >> 8) & 0xFF;

   248 	buf[5] = end_of_disc & 0xFF;

   249 	return PKT_ERR_OK;

   250     } else {

   251 	session--;

   252 	for( i=0; i<image->track_count; i++ ) {

   253 	    if( image->track[i].session == session ) {

   254 		buf[2] = i+1; /* first track of session */

   255 		buf[3] = (image->track[i].lba >> 16) & 0xFF;

   256 		buf[4] = (image->track[i].lba >> 8) & 0xFF;

   257 		buf[5] = image->track[i].lba & 0xFF;

   258 		return PKT_ERR_OK;

   259 	    }

   260 	}

   261 	return PKT_ERR_BADFIELD; /* No such session */

   262     }

   263 }

   265 static gdrom_error_t gdrom_image_read_position( gdrom_disc_t disc, uint32_t lba, unsigned char *buf )

   266 {

   267     gdrom_image_t image = (gdrom_image_t)disc;

   268     int track_no = gdrom_image_get_track_by_lba( image, lba );

   269     if( track_no == -1 ) {

   270 	track_no = 1;

   271 	lba = 150;

   272     }

   273     struct gdrom_track *track = &image->track[track_no-1];

   274     uint32_t offset = lba - track->lba;

   275     buf[4] = track->flags;

   276     buf[5] = track_no;

   277     buf[6] = 0x01; /* ?? */

   278     buf[7] = (offset >> 16) & 0xFF;

   279     buf[8] = (offset >> 8) & 0xFF;

   280     buf[9] = offset & 0xFF;

   281     buf[10] = 0;

   282     buf[11] = (lba >> 16) & 0xFF;

   283     buf[12] = (lba >> 8) & 0xFF;

   284     buf[13] = lba & 0xFF;

   285     return PKT_ERR_OK;

   286 }

   288 static int gdrom_image_drive_status( gdrom_disc_t disc )

   289 {

   290     gdrom_image_t image = (gdrom_image_t)disc;

   291     return image->disc_type | IDE_DISC_READY;

   292 }

   294 void gdrom_image_dump_info( gdrom_disc_t d ) {

   295     gdrom_image_t disc = (gdrom_image_t)d;

   296     int i;

   297     int last_session = disc->track[disc->track_count-1].session;

   298     gboolean is_bootable = FALSE;

   300     INFO( "Disc ID: %s, %d tracks in %d sessions", disc->mcn, disc->track_count,

   301 	  disc->track[disc->track_count-1].session + 1 );

   302     if( last_session > 0 ) {

   303 	/* Boot track is the first data track of the last session, provided that it

   304 	 * cannot be a single-session disc.

   305 	 */

   306 	int boot_track = -1;

   307 	for( i=disc->track_count-1; i>=0 && disc->track[i].session == last_session; i-- ) {

   308 	    if( disc->track[i].flags & TRACK_DATA ) {

   309 		boot_track = i;

   310 	    }

   311 	}

   312 	if( boot_track != -1 ) {

   313 	    unsigned char boot_sector[MAX_SECTOR_SIZE];

   314 	    uint32_t length = sizeof(boot_sector);

   315 	    if( d->read_sector( d, disc->track[boot_track].lba, 0x28,

   316 				   boot_sector, &length ) == PKT_ERR_OK ) {

   317 		bootstrap_dump(boot_sector, FALSE);

   318 		is_bootable = TRUE;

   319 	    }

   320 	}

   321     }

   322     if( !is_bootable ) {

   323 	WARN( "Disc does not appear to be bootable" );

   324     }

   325 }