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filename src/gdrom/gdrom.c
changeset 245:a1d0655a88d3
prev237:6f1a429c9d12
next342:850502f0e8de
author nkeynes
date Mon Jan 15 12:17:02 2007 +0000 (17 years ago)
permissions -rw-r--r--
last change Fix output of yuv_decode() (yes, again...)
view annotate diff log raw 
     1 /**

     2  * $Id: gdrom.c,v 1.11 2006-12-19 09:52:56 nkeynes Exp $

     3  *

     4  * GD-Rom  access 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  */

    18 

    19 #include <stdio.h>

    20 #include <fcntl.h>

    21 #include <errno.h>

    22 #include "gdrom/ide.h"

    23 #include "gdrom/gdrom.h"

    24 #include "gdrom/packet.h"

    25 #include "dream.h"

    26 

    27 static void gdrom_image_destroy( gdrom_disc_t );

    28 static gdrom_error_t gdrom_image_read_sectors( gdrom_disc_t, uint32_t, uint32_t, int, char *, uint32_t * );

    29 

    30 gdrom_image_class_t gdrom_image_classes[] = { &linux_device_class, &nrg_image_class, &cdi_image_class, NULL };

    31 

    32 gdrom_disc_t gdrom_disc = NULL;

    33 

    34 char *gdrom_mode_names[] = { "Mode1", "Mode2", "XA 1", "XA2", "Audio", "GD-Rom" };

    35 uint32_t gdrom_sector_size[] = { 2048, 2336, 2048, 2324, 2352, 2336 };

    36 

    37 gdrom_disc_t gdrom_image_open( const gchar *filename )

    38 {

    39     const gchar *ext = strrchr(filename, '.');

    40     gdrom_disc_t disc = NULL;

    41 

    42     int fd = open( filename, O_RDONLY | O_NONBLOCK );

    43     FILE *f;

    44     int i,j;

    45     gdrom_image_class_t extclz = NULL;

    46 

    47     if( fd == -1 ) {

    48 	ERROR("Unable to open file '%s': %s", filename, strerror(errno));

    49 	return NULL;

    50     }

    51 

    52     f = fdopen(fd, "ro");

    53 

    54 

    55     /* try extensions */

    56     if( ext != NULL ) {

    57 	ext++; /* Skip the '.' */

    58 	for( i=0; gdrom_image_classes[i] != NULL; i++ ) {

    59 	    if( gdrom_image_classes[i]->extension != NULL &&

    60 		strcasecmp( gdrom_image_classes[i]->extension, ext ) == 0 ) {

    61 		extclz = gdrom_image_classes[i];

    62 		if( extclz->is_valid_file(f) ) {

    63 		    disc = extclz->open_image_file(filename, f);

    64 		    if( disc != NULL )

    65 			return disc;

    66 		}

    67 		break;

    68 	    }

    69 	}

    70     }

    71 

    72     /* Okay, fall back to magic */

    73     gboolean recognized = FALSE;

    74     for( i=0; gdrom_image_classes[i] != NULL; i++ ) {

    75 	if( gdrom_image_classes[i] != extclz &&

    76 	    gdrom_image_classes[i]->is_valid_file(f) ) {

    77 	    recognized = TRUE;

    78 	    disc = gdrom_image_classes[i]->open_image_file(filename, f);

    79 	    if( disc != NULL )

    80 		return disc;

    81 	}

    82     }

    83 

    84     if( !recognized ) {

    85 	ERROR( "Unable to open disc %s: Unsupported format", filename );

    86     }

    87     fclose(f);

    88     return NULL;

    89 }

    90 

    91 

    92 gdrom_disc_t gdrom_image_new( FILE *file )

    93 {

    94     struct gdrom_disc *disc = (struct gdrom_disc *)calloc(1, sizeof(struct gdrom_disc));

    95     if( disc == NULL )

    96 	return NULL;

    97     disc->read_sectors = gdrom_image_read_sectors;

    98     disc->close = gdrom_image_destroy;

    99     disc->disc_type = IDE_DISC_CDROM;

   100     disc->file = file;

   101     return disc;

   102 }

   103 

   104 static void gdrom_image_destroy( gdrom_disc_t disc )

   105 {

   106     if( disc->file != NULL ) {

   107 	fclose(disc->file);

   108 	disc->file = NULL;

   109     }

   110     free( disc );

   111 }

   112 

   113 static gdrom_error_t gdrom_image_read_sectors( gdrom_disc_t disc, uint32_t sector,

   114 					       uint32_t sector_count, int mode, char *buf,

   115 					       uint32_t *length )

   116 {

   117     int i, file_offset, read_len;

   118     struct gdrom_track *track = NULL;

   119 

   120     for( i=0; i<disc->track_count; i++ ) {

   121 	if( disc->track[i].lba <= sector && 

   122 	    (sector + sector_count) <= (disc->track[i].lba + disc->track[i].sector_count) ) {

   123 	    track = &disc->track[i];

   124 	    break;

   125 	}

   126     }

   127     if( track == NULL )

   128 	return PKT_ERR_BADREAD;

   129 

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

   131     read_len = track->sector_size * sector_count;

   132 

   133     switch( mode ) {

   134     case GDROM_GD:

   135 	// Temporarily comment this out - it's wrong, but...

   136 	//	if( track->mode != GDROM_GD ) 

   137 	//    return PKT_ERR_BADREADMODE;

   138 	// break;

   139     case GDROM_MODE1:

   140     case GDROM_MODE2_XA1:

   141 	switch( track->mode ) {

   142 	case GDROM_MODE1:

   143 	case GDROM_MODE2_XA1:

   144 	    fseek( disc->file, file_offset, SEEK_SET );

   145 	    fread( buf, track->sector_size, sector_count, disc->file );

   146 	    break;

   147 	case GDROM_MODE2:

   148 	    read_len = sector_count * 2048;

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

   150 	    while( sector_count > 0 ) {

   151 		fseek( disc->file, file_offset, SEEK_SET );

   152 		fread( buf, 2048, 1, disc->file );

   153 		file_offset += track->sector_size;

   154 		buf += 2048;

   155 		sector_count--;

   156 	    }

   157 	    break;

   158 	default:

   159 	    return PKT_ERR_BADREADMODE;

   160 	}

   161 	break;

   162     default:

   163 	return PKT_ERR_BADREADMODE;

   164     }

   165 	    

   166     *length = read_len;

   167     return PKT_ERR_OK;

   168 }

   169 

   170 uint32_t gdrom_read_sectors( uint32_t sector, uint32_t sector_count,

   171 			     int mode, char *buf, uint32_t *length )

   172 {

   173     if( gdrom_disc == NULL )

   174 	return PKT_ERR_NODISC; /* No media */

   175     return gdrom_disc->read_sectors( gdrom_disc, sector, sector_count, mode, buf, length );

   176 }

   177 

   178 

   179 void gdrom_dump_disc_info( gdrom_disc_t disc ) {

   180     int i;

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

   182     gboolean is_bootable = FALSE;

   183 

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

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

   186     if( last_session > 0 ) {

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

   188 	 * cannot be a single-session disc.

   189 	 */

   190 	int boot_track = -1;

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

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

   193 		boot_track = i;

   194 	    }

   195 	}

   196 	if( boot_track != -1 ) {

   197 	    char boot_sector[2048];

   198 	    uint32_t length = sizeof(boot_sector);

   199 	    if( disc->read_sectors( disc, disc->track[boot_track].lba, 1, GDROM_MODE1,

   200 				    boot_sector, &length ) == PKT_ERR_OK ) {

   201 		bootstrap_dump(boot_sector, FALSE);

   202 		is_bootable = TRUE;

   203 	    }

   204 	}

   205     }

   206     if( !is_bootable )

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

   208 }

   209 

   210 gdrom_error_t gdrom_get_toc( char *buf ) 

   211 {

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

   213     int i;

   214 

   215     if( gdrom_disc == NULL )

   216 	return PKT_ERR_NODISC;

   217 

   218     for( i=0; i<gdrom_disc->track_count; i++ ) {

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

   220     }

   221     toc->first = 0x0100 | gdrom_disc->track[0].flags;

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

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

   224 	gdrom_disc->track[i-1].flags;

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

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

   227     return PKT_ERR_OK;

   228 }

   229 

   230 gdrom_error_t gdrom_get_info( char *buf, int session )

   231 {

   232     if( gdrom_disc == NULL )

   233 	return PKT_ERR_NODISC;

   234     struct gdrom_track *last_track = &gdrom_disc->track[gdrom_disc->track_count-1];

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

   236     int i;

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

   238     buf[1] = 0;

   239 

   240     if( session == 0 ) {

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

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

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

   244 	buf[5] = end_of_disc & 0xFF;

   245 	return PKT_ERR_OK;

   246     } else {

   247 	session--;

   248 	for( i=0; i<gdrom_disc->track_count; i++ ) {

   249 	    if( gdrom_disc->track[i].session == session ) {

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

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

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

   253 		buf[5] = gdrom_disc->track[i].lba & 0xFF;

   254 		return PKT_ERR_OK;

   255 	    }

   256 	}

   257 	return PKT_ERR_BADFIELD; /* No such session */

   258     }

   259 	

   260 }

   261 

   262 gdrom_track_t gdrom_get_track( int trackno ) {

   263     if( gdrom_disc == NULL || trackno < 1 || trackno > 99 ) {

   264 	return NULL;

   265     } else {

   266 	return &gdrom_disc->track[trackno-1];

   267     }

   268 }

   269 

   270 uint8_t gdrom_get_track_no_by_lba( uint32_t lba ) {

   271     int i;

   272     if( gdrom_disc != NULL ) {

   273 	for( i=0; i<gdrom_disc->track_count; i++ ) {

   274 	    if( gdrom_disc->track[i].lba <= lba && 

   275 		lba <= (gdrom_disc->track[i].lba + gdrom_disc->track[i].sector_count) ) {

   276 		return i+1;

   277 	    }

   278 	}

   279     }

   280     return -1;

   281 }

   282 

   283 void gdrom_mount_disc( gdrom_disc_t disc ) 

   284 {

   285     gdrom_unmount_disc();

   286     gdrom_disc = disc;

   287     idereg.disc = disc->disc_type | IDE_DISC_READY;

   288     gdrom_dump_disc_info( disc );

   289 }

   290 

   291 gdrom_disc_t gdrom_mount_image( const gchar *filename )

   292 {

   293     gdrom_disc_t disc = gdrom_image_open(filename);

   294     if( disc != NULL )

   295 	gdrom_mount_disc( disc );

   296     return disc;

   297 }

   298 

   299 void gdrom_unmount_disc( ) 

   300 {

   301     if( gdrom_disc != NULL ) {

   302 	gdrom_disc->close(gdrom_disc);

   303     }

   304     gdrom_disc = NULL;

   305     idereg.disc = IDE_DISC_NONE;

   306 }

   307 

   308 gboolean gdrom_is_mounted( void ) 

   309 {

   310     return gdrom_disc != NULL;

   311 }
.