4 * VMU volume (ie block device) support
6 * Copyright (c) 2009 Nathan Keynes.
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.
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.
26 #include "vmu/vmuvol.h"
30 #define VMU_MAX_PARTITIONS 256
31 #define VMU_MAX_BLOCKS 65536 /* Actually slightly less than this, but it'll do */
33 typedef struct vmu_partition {
34 struct vmu_volume_metadata metadata;
40 const gchar *display_name;
41 vmu_partnum_t part_count;
43 struct vmu_partition part[0];
46 /* On-VMU structures, courtesy of Marcus Comstedt */
47 struct vmu_superblock {
61 /* remainder unknown */
70 uint16_t blksize; /* Size in blocks*/
71 uint16_t hdroff; /* Header offset in blocks */
75 #define MD(vmu,ptno) ((vmu)->part[ptno].metadata)
77 #define VMU_BLOCK(vmu,ptno,blkno) (&(vmu)->part[ptno].blocks[(blkno)*VMU_BLOCK_SIZE])
79 #define VMU_FAT_ENTRY(vmu,pt,ent) ((uint16_t *)VMU_BLOCK(vmu, pt, (MD(vmu,pt).fat_block - ((ent)>>8))))[(ent)&0xFF]
81 #define FAT_EMPTY 0xFFFC
82 #define FAT_EOF 0xFFFA
84 static const struct vmu_volume_metadata default_metadata = { 255, 255, 254, 1, 253, 13, 0, 200, {31, 0, 128} };
86 vmu_volume_t vmu_volume_new_default( const gchar *display_name )
88 vmu_volume_t vol = g_malloc0( sizeof(struct vmu_volume) + sizeof(struct vmu_partition) );
91 memcpy( &vol->part[0].metadata, &default_metadata, sizeof(struct vmu_volume_metadata) );
92 vol->part[0].block_count = VMU_DEFAULT_VOL_BLOCKS;
93 vol->part[0].blocks = g_malloc0( VMU_DEFAULT_VOL_BLOCKS * VMU_BLOCK_SIZE );
94 vol->display_name = display_name == NULL ? NULL : g_strdup(display_name);
95 vmu_volume_format( vol, 0, TRUE );
99 void vmu_volume_destroy( vmu_volume_t vol )
105 for( i=0; i<vol->part_count; i++ ) {
106 g_free( vol->part[i].blocks );
107 vol->part[i].blocks = NULL;
109 if( vol->display_name ) {
110 g_free( (char *)vol->display_name );
111 vol->display_name = NULL;
116 void vmu_volume_format( vmu_volume_t vol, vmu_partnum_t pt, gboolean quick )
118 if( pt >= vol->part_count ) {
123 /* Wipe it completely first */
124 memset( vol->part[pt].blocks, 0, (vol->part[pt].block_count) * VMU_BLOCK_SIZE );
127 struct vmu_volume_metadata *meta = &vol->part[pt].metadata;
128 unsigned int fatblkno = meta->fat_block;
129 unsigned int dirblkno = meta->dir_block;
131 /* Write superblock */
132 struct vmu_superblock *super = (struct vmu_superblock *)VMU_BLOCK(vol,pt, meta->super_block);
133 memset( super->magic, 0x55, 16 );
134 memset( &super->colour_flag, 0, 240 ); /* Blank the rest for now */
135 super->fat_block = meta->fat_block;
136 super->fat_size = meta->fat_size;
137 super->dir_block = meta->dir_block;
138 super->user_size = meta->user_size;
140 /* Write file allocation tables */
142 for( j=0; j<meta->fat_size; j++ ) {
143 uint16_t *fat = (uint16_t *)VMU_BLOCK(vol,pt,fatblkno-j);
144 for( i=0; i<256; i++ ) {
149 /* Fill in the system allocations in the FAT */
150 for( i=0; i<meta->fat_size-1; i++ ) {
151 VMU_FAT_ENTRY(vol,pt,fatblkno-i) = fatblkno-i-1;
153 VMU_FAT_ENTRY(vol,pt,fatblkno - i) = FAT_EOF;
154 for( i=0; i<meta->dir_size-1; i++ ) {
155 VMU_FAT_ENTRY(vol,pt,dirblkno-i) = dirblkno-i-1;
157 VMU_FAT_ENTRY(vol,pt,dirblkno-i) = FAT_EOF;
159 /* If quick-format, blank the directory. Otherwise it's already been done */
161 memset( VMU_BLOCK(vol,pt,dirblkno-meta->dir_size+1),
162 0, meta->dir_size * VMU_BLOCK_SIZE );
166 /*************************** File load/save ********************************/
169 * Current file has 1 META chunk for all volume metadata, followed by a
170 * DATA chunk for each partition's block data. The META chunk is required to
171 * occur before any DATA blocks.
172 * Unknown chunks are skipped to allow for forwards compatibility if/when
173 * we add the VMU runtime side of things
176 struct vmu_file_header {
181 uint32_t display_name_len;
182 char display_name[0];
185 struct vmu_chunk_header {
191 gboolean vmu_volume_save( const gchar *filename, vmu_volume_t vol, gboolean create_only )
193 struct vmu_file_header head;
194 struct vmu_chunk_header chunk;
197 gchar *tempfile = get_filename_at(filename, ".XXXXXXX");
198 int fd = mkstemp( tempfile );
204 FILE *f = fdopen( fd, "w+" );
208 memcpy( head.magic, VMU_FILE_MAGIC, 16 );
209 head.version = VMU_FILE_VERSION;
210 head.part_count = vol->part_count;
211 head.display_name_len = vol->display_name == NULL ? 0 : (strlen(vol->display_name)+1);
212 head.head_len = sizeof(head) + head.display_name_len;
213 fwrite( &head, sizeof(head), 1, f );
214 if( vol->display_name != NULL ) {
215 fwrite( vol->display_name, head.display_name_len, 1, f );
219 memcpy( chunk.name, "META", 4 );
220 chunk.length = sizeof(struct vmu_volume_metadata) * vol->part_count;
221 fwrite( &chunk, sizeof(chunk), 1, f );
222 for( i=0; i < vol->part_count; i++ ) {
223 fwrite( &vol->part[i].metadata, sizeof(struct vmu_volume_metadata), 1, f );
226 /* partition DATA chunks */
227 for( i=0; i< vol->part_count; i++ ) {
228 memcpy( chunk.name, "DATA", 4 );
230 if( fwrite( &chunk, sizeof(chunk), 1, f ) != 1 ) goto cleanup;
231 long posn = ftell(f);
232 if( fwrite( &vol->part[i].block_count, sizeof(vol->part[i].block_count), 1, f ) != 1 ) goto cleanup;
233 fwrite_gzip( vol->part[i].blocks, vol->part[i].block_count, VMU_BLOCK_SIZE, f );
235 fseek( f, posn - sizeof(chunk.length), SEEK_SET );
236 chunk.length = end-posn;
237 if( fwrite( &chunk.length, sizeof(chunk.length), 1, f ) != 1 ) goto cleanup;
238 fseek( f, end, SEEK_SET );
243 if( rename(tempfile, filename) != 0 )
259 vmu_volume_t vmu_volume_load( const gchar *filename )
261 struct vmu_file_header head;
262 struct vmu_chunk_header chunk;
266 FILE *f = fopen( filename, "ro" );
268 ERROR( "Unable to open VMU file '%s': %s", filename, strerror(errno) );
272 if( fread( &head, sizeof(head), 1, f ) != 1 ||
273 memcmp(head.magic, VMU_FILE_MAGIC, 16) != 0 ||
274 head.part_count > VMU_MAX_PARTITIONS ||
275 head.head_len < (sizeof(head) + head.display_name_len) ) {
277 ERROR( "Unable to load VMU '%s': bad file header", filename );
281 vol = (vmu_volume_t)g_malloc0( sizeof(struct vmu_volume) + sizeof(struct vmu_partition)*head.part_count );
282 vol->part_count = head.part_count;
284 if( head.display_name_len != 0 ) {
285 vol->display_name = g_malloc( head.display_name_len );
286 fread( (char *)vol->display_name, head.display_name_len, 1, f );
288 fseek( f, head.head_len, SEEK_SET );
290 gboolean have_meta = FALSE;
292 while( !feof(f) && fread( &chunk, sizeof(chunk), 1, f ) == 1 ) {
293 if( memcmp( &chunk.name, "META", 4 ) == 0 ) {
294 if( have_meta || chunk.length != head.part_count * sizeof(struct vmu_volume_metadata) ) {
295 vmu_volume_destroy(vol);
297 ERROR( "Unable to load VMU '%s': bad metadata size (expected %d but was %d)", filename,
298 head.part_count * sizeof(struct vmu_volume_metadata), chunk.length );
301 for( i=0; i<head.part_count; i++ ) {
302 fread( &vol->part[i].metadata, sizeof(struct vmu_volume_metadata), 1, f );
305 } else if( memcmp( &chunk.name, "DATA", 4 ) == 0 ) {
306 uint32_t block_count;
307 fread( &block_count, sizeof(block_count), 1, f );
308 if( next_part >= vol->part_count || block_count >= VMU_MAX_BLOCKS ) {
309 // Too many partitions / blocks
310 vmu_volume_destroy(vol);
312 ERROR( "Unable to load VMU '%s': too large (%d/%d)", filename, next_part, block_count );
315 vol->part[next_part].block_count = block_count;
316 vol->part[next_part].blocks = g_malloc(block_count*VMU_BLOCK_SIZE);
317 fread_gzip(vol->part[next_part].blocks, VMU_BLOCK_SIZE, block_count, f );
320 // else skip unknown block
321 fseek( f, SEEK_CUR, chunk.length );
322 WARN( "Unexpected VMU data chunk: '%4.4s'", chunk.name );
328 if( !have_meta || next_part != vol->part_count ) {
329 vmu_volume_destroy( vol );
336 /*************************** Accessing data ********************************/
337 const char *vmu_volume_get_display_name( vmu_volume_t vol )
339 return vol->display_name;
342 void vmu_volume_set_display_name( vmu_volume_t vol, const gchar *name )
344 if( vol->display_name != NULL ) {
345 g_free( (char *)vol->display_name );
348 vol->display_name = NULL;
350 vol->display_name = g_strdup(name);
354 gboolean vmu_volume_is_dirty( vmu_volume_t vol )
359 gboolean vmu_volume_read_block( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned char *out )
361 if( pt >= vol->part_count || block >= vol->part[pt].block_count ) {
365 memcpy( out, VMU_BLOCK(vol,pt,block), VMU_BLOCK_SIZE );
369 gboolean vmu_volume_write_block( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned char *in )
371 if( pt >= vol->part_count || block >= vol->part[pt].block_count ) {
374 memcpy( VMU_BLOCK(vol,pt,block), in, VMU_BLOCK_SIZE );
379 gboolean vmu_volume_write_phase( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned int phase, unsigned char *in )
381 if( pt >= vol->part_count || block >= vol->part[pt].block_count || phase >= 4 ) {
384 memcpy( VMU_BLOCK(vol,pt,block) + (phase*128), in, VMU_BLOCK_SIZE/4 );
389 const struct vmu_volume_metadata *vmu_volume_get_metadata( vmu_volume_t vol, vmu_partnum_t partition )
391 if( partition >= vol->part_count ) {
394 return &vol->part[partition].metadata;
.