nkeynes@1034: /**
nkeynes@1035:  * $Id$
nkeynes@1034:  *
nkeynes@1034:  * VMU volume (ie block device) support
nkeynes@1034:  *
nkeynes@1034:  * Copyright (c) 2009 Nathan Keynes.
nkeynes@1034:  *
nkeynes@1034:  * This program is free software; you can redistribute it and/or modify
nkeynes@1034:  * it under the terms of the GNU General Public License as published by
nkeynes@1034:  * the Free Software Foundation; either version 2 of the License, or
nkeynes@1034:  * (at your option) any later version.
nkeynes@1034:  *
nkeynes@1034:  * This program is distributed in the hope that it will be useful,
nkeynes@1034:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
nkeynes@1034:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nkeynes@1034:  * GNU General Public License for more details.
nkeynes@1034:  */
nkeynes@1034: 
nkeynes@1034: #include <glib/gmem.h>
nkeynes@1034: #include <glib/gstrfuncs.h>
nkeynes@1034: #include <string.h>
nkeynes@1034: #include <stdio.h>
nkeynes@1034: #include <fcntl.h>
nkeynes@1034: #include <errno.h>
nkeynes@1034: 
nkeynes@1034: #include "vmu/vmuvol.h"
nkeynes@1034: #include "dream.h"
nkeynes@1034: 
nkeynes@1034: #define VMU_MAX_PARTITIONS 256
nkeynes@1034: #define VMU_MAX_BLOCKS 65536 /* Actually slightly less than this, but it'll do */
nkeynes@1034: 
nkeynes@1034: typedef struct vmu_partition {
nkeynes@1034:     struct vmu_volume_metadata metadata;
nkeynes@1034:     uint32_t block_count;
nkeynes@1034:     char *blocks;
nkeynes@1034: } *vmu_partition_t;
nkeynes@1034: 
nkeynes@1034: struct vmu_volume {
nkeynes@1034:     const gchar *display_name;
nkeynes@1034:     vmu_partnum_t part_count;
nkeynes@1034:     gboolean dirty;
nkeynes@1034:     struct vmu_partition part[0];
nkeynes@1034: };
nkeynes@1034: 
nkeynes@1034: /* On-VMU structures, courtesy of Marcus Comstedt */ 
nkeynes@1034: struct vmu_superblock {
nkeynes@1034:     char magic[16];
nkeynes@1034:     uint8_t colour_flag;
nkeynes@1034:     uint8_t bgra[4];
nkeynes@1034:     uint8_t pad1[27];
nkeynes@1034:     char timestamp[8];
nkeynes@1034:     char pad2[8];
nkeynes@1034:     char unknown[6];
nkeynes@1034:     uint16_t fat_block;
nkeynes@1034:     uint16_t fat_size;
nkeynes@1034:     uint16_t dir_block;
nkeynes@1034:     uint16_t dir_size;
nkeynes@1034:     uint16_t icon_shape;
nkeynes@1034:     uint16_t user_size;
nkeynes@1034:     /* remainder unknown */
nkeynes@1034: };
nkeynes@1034: 
nkeynes@1034: struct vmu_direntry {
nkeynes@1034:     uint8_t filetype;
nkeynes@1034:     uint8_t copy_flag;
nkeynes@1034:     uint16_t blkno;
nkeynes@1034:     char filename[12];
nkeynes@1034:     char timestamp[8];
nkeynes@1034:     uint16_t blksize; /* Size in blocks*/
nkeynes@1034:     uint16_t hdroff; /* Header offset in blocks */
nkeynes@1034:     char pad[4];
nkeynes@1034: };
nkeynes@1034: 
nkeynes@1034: #define MD(vmu,ptno) ((vmu)->part[ptno].metadata)
nkeynes@1034: 
nkeynes@1034: #define VMU_BLOCK(vmu,ptno,blkno) (&(vmu)->part[ptno].blocks[(blkno)*VMU_BLOCK_SIZE])
nkeynes@1034: 
nkeynes@1034: #define VMU_FAT_ENTRY(vmu,pt,ent)  ((uint16_t *)VMU_BLOCK(vmu, pt, (MD(vmu,pt).fat_block - ((ent)>>8))))[(ent)&0xFF]
nkeynes@1034: 
nkeynes@1034: #define FAT_EMPTY 0xFFFC
nkeynes@1034: #define FAT_EOF   0xFFFA
nkeynes@1034: 
nkeynes@1034: static const struct vmu_volume_metadata default_metadata = { 255, 255, 254, 1, 253, 13, 0, 200, 31, 0, 128 };
nkeynes@1034: 
nkeynes@1034: vmu_volume_t vmu_volume_new_default( const gchar *display_name )
nkeynes@1034: {
nkeynes@1034:     vmu_volume_t vol = g_malloc0( sizeof(struct vmu_volume) + sizeof(struct vmu_partition) );
nkeynes@1034:     vol->part_count = 1;
nkeynes@1034:     vol->dirty = FALSE;
nkeynes@1034:     memcpy( &vol->part[0].metadata, &default_metadata, sizeof(struct vmu_volume_metadata) );
nkeynes@1034:     vol->part[0].block_count = VMU_DEFAULT_VOL_BLOCKS;
nkeynes@1034:     vol->part[0].blocks = g_malloc0( VMU_DEFAULT_VOL_BLOCKS * VMU_BLOCK_SIZE );
nkeynes@1034:     vol->display_name = display_name == NULL ? NULL : g_strdup(display_name);
nkeynes@1034:     vmu_volume_format( vol, 0, TRUE );
nkeynes@1034:     return vol;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: void vmu_volume_destroy( vmu_volume_t vol )
nkeynes@1034: {
nkeynes@1034:     int i;
nkeynes@1034:     if( vol == NULL )
nkeynes@1034:         return;
nkeynes@1034:     
nkeynes@1034:     for( i=0; i<vol->part_count; i++ ) {
nkeynes@1034:         g_free( vol->part[i].blocks );
nkeynes@1034:         vol->part[i].blocks = NULL;
nkeynes@1034:     }
nkeynes@1034:     if( vol->display_name ) {
nkeynes@1034:         g_free( (char *)vol->display_name );
nkeynes@1034:         vol->display_name = NULL;
nkeynes@1034:     }
nkeynes@1034:     g_free(vol);
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: void vmu_volume_format( vmu_volume_t vol, vmu_partnum_t pt, gboolean quick )
nkeynes@1034: {
nkeynes@1034:     if( pt >= vol->part_count ) {
nkeynes@1034:         return;
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     if( !quick ) {
nkeynes@1034:         /* Wipe it completely first */
nkeynes@1034:         memset( vol->part[pt].blocks, 0, (vol->part[pt].block_count) * VMU_BLOCK_SIZE );
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     struct vmu_volume_metadata *meta = &vol->part[pt].metadata;
nkeynes@1034:     unsigned int fatblkno = meta->fat_block;
nkeynes@1034:     unsigned int dirblkno = meta->dir_block;
nkeynes@1034:     
nkeynes@1034:     /* Write superblock */
nkeynes@1034:     struct vmu_superblock *super = (struct vmu_superblock *)VMU_BLOCK(vol,pt, meta->super_block);
nkeynes@1034:     memset( super->magic, 0x55, 16 );
nkeynes@1034:     memset( &super->colour_flag, 0, 240 ); /* Blank the rest for now */
nkeynes@1034:     super->fat_block = meta->fat_block;
nkeynes@1034:     super->fat_size = meta->fat_size;
nkeynes@1034:     super->dir_block = meta->dir_block;
nkeynes@1034:     super->user_size = meta->user_size;
nkeynes@1034:     
nkeynes@1034:     /* Write file allocation tables */
nkeynes@1034:     int i,j;
nkeynes@1034:     for( j=0; j<meta->fat_size; j++ ) {
nkeynes@1034:         uint16_t *fat = (uint16_t *)VMU_BLOCK(vol,pt,fatblkno-j); 
nkeynes@1034:         for( i=0; i<256; i++ ) {
nkeynes@1034:             fat[i] = FAT_EMPTY;
nkeynes@1034:         }
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     /* Fill in the system allocations in the FAT */
nkeynes@1034:     for( i=0; i<meta->fat_size-1; i++ ) {
nkeynes@1034:         VMU_FAT_ENTRY(vol,pt,fatblkno-i) = fatblkno-i-1;
nkeynes@1034:     }
nkeynes@1034:     VMU_FAT_ENTRY(vol,pt,fatblkno - i) = FAT_EOF;
nkeynes@1034:     for( i=0; i<meta->dir_size-1; i++ ) {
nkeynes@1034:         VMU_FAT_ENTRY(vol,pt,dirblkno-i) = dirblkno-i-1;
nkeynes@1034:     }
nkeynes@1034:     VMU_FAT_ENTRY(vol,pt,dirblkno-i) = FAT_EOF;
nkeynes@1034:   
nkeynes@1034:     /* If quick-format, blank the directory. Otherwise it's already been done */
nkeynes@1034:     if( quick ) {
nkeynes@1034:         memset( VMU_BLOCK(vol,pt,dirblkno-meta->dir_size+1),
nkeynes@1034:                 0, meta->dir_size * VMU_BLOCK_SIZE );
nkeynes@1034:     }
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: /*************************** File load/save ********************************/
nkeynes@1034: 
nkeynes@1034: /**
nkeynes@1034:  * Current file has 1 META chunk for all volume metadata, followed by a
nkeynes@1034:  * DATA chunk for each partition's block data. The META chunk is required to
nkeynes@1034:  * occur before any DATA blocks.
nkeynes@1034:  * Unknown chunks are skipped to allow for forwards compatibility if/when
nkeynes@1034:  * we add the VMU runtime side of things
nkeynes@1034:  */
nkeynes@1034: 
nkeynes@1034: struct vmu_file_header {
nkeynes@1034:     char magic[16];
nkeynes@1034:     uint32_t version;
nkeynes@1034:     uint32_t head_len;
nkeynes@1034:     uint32_t part_count;
nkeynes@1034:     uint32_t display_name_len;
nkeynes@1034:     char display_name[0];
nkeynes@1034: };
nkeynes@1034: 
nkeynes@1034: struct vmu_chunk_header {
nkeynes@1034:     char name[4];
nkeynes@1034:     uint32_t length;
nkeynes@1034: };
nkeynes@1034: 
nkeynes@1034: 
nkeynes@1034: 
nkeynes@1034: gboolean vmu_volume_save( const gchar *filename, vmu_volume_t vol, gboolean create_only )
nkeynes@1034: {
nkeynes@1034:     struct vmu_file_header head;
nkeynes@1034:     struct vmu_chunk_header chunk;
nkeynes@1034:     int i;
nkeynes@1034:     
nkeynes@1034:     FILE *f = fopen( filename, (create_only ? "wx" : "w") ); /* Portable? */
nkeynes@1034:     if( f == NULL ) {
nkeynes@1034:         return FALSE;
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     /* File header */
nkeynes@1034:     memcpy( head.magic, VMU_FILE_MAGIC, 16 );
nkeynes@1034:     head.version = VMU_FILE_VERSION;
nkeynes@1034:     head.part_count = vol->part_count;
nkeynes@1034:     head.display_name_len = vol->display_name == NULL ? 0 : (strlen(vol->display_name)+1);
nkeynes@1034:     head.head_len = sizeof(head) + head.display_name_len;
nkeynes@1034:     fwrite( &head, sizeof(head), 1, f );
nkeynes@1034:     if( vol->display_name != NULL ) {
nkeynes@1034:         fwrite( vol->display_name, head.display_name_len, 1, f );
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     /* METAdata chunk */
nkeynes@1034:     memcpy( chunk.name, "META", 4 );
nkeynes@1034:     chunk.length = sizeof(struct vmu_volume_metadata) * vol->part_count;
nkeynes@1034:     fwrite( &chunk, sizeof(chunk), 1, f );
nkeynes@1034:     for( i=0; i < vol->part_count; i++ ) {
nkeynes@1034:         fwrite( &vol->part[i].metadata, sizeof(struct vmu_volume_metadata), 1, f );
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     /* partition DATA chunks */
nkeynes@1034:     for( i=0; i< vol->part_count; i++ ) {
nkeynes@1034:         memcpy( chunk.name, "DATA", 4 );
nkeynes@1034:         chunk.length = 0;
nkeynes@1034:         fwrite( &chunk, sizeof(chunk), 1, f );
nkeynes@1034:         long posn = ftell(f);
nkeynes@1034:         fwrite( &vol->part[i].block_count, sizeof(vol->part[i].block_count), 1, f );
nkeynes@1034:         fwrite_gzip( vol->part[i].blocks, vol->part[i].block_count, VMU_BLOCK_SIZE, f );
nkeynes@1034:         long end = ftell(f);
nkeynes@1034:         fseek( f, posn - sizeof(chunk.length), SEEK_SET );
nkeynes@1034:         chunk.length = end-posn;
nkeynes@1034:         fwrite( &chunk.length, sizeof(chunk.length), 1, f );
nkeynes@1034:         fseek( f, end, SEEK_SET );
nkeynes@1034:     }
nkeynes@1034:     fclose(f);
nkeynes@1034:     vol->dirty = FALSE;
nkeynes@1034:     return TRUE;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: vmu_volume_t vmu_volume_load( const gchar *filename )
nkeynes@1034: {
nkeynes@1034:     struct vmu_file_header head;
nkeynes@1034:     struct vmu_chunk_header chunk;
nkeynes@1034:     vmu_volume_t vol;
nkeynes@1034:     int i;
nkeynes@1034:     
nkeynes@1034:     FILE *f = fopen( filename, "ro" );
nkeynes@1034:     if( f == NULL ) {
nkeynes@1034:         ERROR( "Unable to open VMU file '%s': %s", filename, strerror(errno) );
nkeynes@1034:         return FALSE;
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     if( fread( &head, sizeof(head), 1, f ) != 1 ||
nkeynes@1034:         memcmp(head.magic, VMU_FILE_MAGIC, 16) != 0 ||
nkeynes@1034:         head.part_count > VMU_MAX_PARTITIONS || 
nkeynes@1034:         head.head_len < (sizeof(head) + head.display_name_len) )  {
nkeynes@1034:         fclose(f);
nkeynes@1034:         ERROR( "Unable to load VMU '%s': bad file header", filename );
nkeynes@1034:         return NULL;
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     vol = (vmu_volume_t)g_malloc0( sizeof(struct vmu_volume) + sizeof(struct vmu_partition)*head.part_count );
nkeynes@1034:     vol->part_count = head.part_count;
nkeynes@1034:     vol->dirty = FALSE;
nkeynes@1034:     if( head.display_name_len != 0 ) {
nkeynes@1034:         vol->display_name = g_malloc( head.display_name_len );
nkeynes@1034:         fread( (char *)vol->display_name, head.display_name_len, 1, f );
nkeynes@1034:     }
nkeynes@1034:     fseek( f, head.head_len, SEEK_SET );
nkeynes@1034:     
nkeynes@1034:     gboolean have_meta = FALSE;
nkeynes@1034:     int next_part = 0;
nkeynes@1034:     while( !feof(f) && fread( &chunk, sizeof(chunk), 1, f ) == 1 ) {
nkeynes@1034:         if( memcmp( &chunk.name, "META", 4 ) == 0 ) {
nkeynes@1034:             if( have_meta || chunk.length != head.part_count * sizeof(struct vmu_volume_metadata) ) {
nkeynes@1034:                 vmu_volume_destroy(vol);
nkeynes@1034:                 fclose(f);
nkeynes@1034:                 ERROR( "Unable to load VMU '%s': bad metadata size (expected %d but was %d)", filename,
nkeynes@1034:                        head.part_count * sizeof(struct vmu_volume_metadata), chunk.length );
nkeynes@1034:                 return NULL;
nkeynes@1034:             }
nkeynes@1034:             for( i=0; i<head.part_count; i++ ) {
nkeynes@1034:                 fread( &vol->part[i].metadata, sizeof(struct vmu_volume_metadata), 1, f );
nkeynes@1034:             }
nkeynes@1034:             have_meta = TRUE;
nkeynes@1034:         } else if( memcmp( &chunk.name, "DATA", 4 ) == 0 ) {
nkeynes@1034:             uint32_t block_count;
nkeynes@1034:             fread( &block_count, sizeof(block_count), 1, f );
nkeynes@1034:             if( next_part >= vol->part_count || block_count >= VMU_MAX_BLOCKS ) {
nkeynes@1034:                 // Too many partitions / blocks
nkeynes@1034:                 vmu_volume_destroy(vol);
nkeynes@1034:                 fclose(f);
nkeynes@1034:                 ERROR( "Unable to load VMU '%s': too large (%d/%d)", filename, next_part, block_count );
nkeynes@1034:                 return NULL;
nkeynes@1034:             }
nkeynes@1034:             vol->part[next_part].block_count = block_count;
nkeynes@1034:             vol->part[next_part].blocks = g_malloc(block_count*VMU_BLOCK_SIZE);
nkeynes@1034:             fread_gzip(vol->part[next_part].blocks, VMU_BLOCK_SIZE, block_count, f );
nkeynes@1034:             next_part++;
nkeynes@1034:         } else {
nkeynes@1034:             // else skip unknown block
nkeynes@1034:             fseek( f, SEEK_CUR, chunk.length );
nkeynes@1034:             WARN( "Unexpected VMU data chunk: '%4.4s'", chunk.name );
nkeynes@1034:         }
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     fclose(f);
nkeynes@1034:     
nkeynes@1034:     if( !have_meta || next_part != vol->part_count ) {
nkeynes@1034:         vmu_volume_destroy( vol );
nkeynes@1034:         return NULL;
nkeynes@1034:     }
nkeynes@1034:     
nkeynes@1034:     return vol;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: /*************************** Accessing data ********************************/
nkeynes@1034: const char *vmu_volume_get_display_name( vmu_volume_t vol ) 
nkeynes@1034: {
nkeynes@1034:     return vol->display_name;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: void vmu_volume_set_display_name( vmu_volume_t vol, const gchar *name )
nkeynes@1034: {
nkeynes@1034:     if( vol->display_name != NULL ) {
nkeynes@1034:         g_free( (char *)vol->display_name );
nkeynes@1034:     }
nkeynes@1034:     if( name == NULL ) {
nkeynes@1034:         vol->display_name = NULL;
nkeynes@1034:     } else {
nkeynes@1034:         vol->display_name = g_strdup(name);
nkeynes@1034:     }
nkeynes@1034: }
nkeynes@1034:     
nkeynes@1034: gboolean vmu_volume_is_dirty( vmu_volume_t vol )
nkeynes@1034: {
nkeynes@1034:     return vol->dirty;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: gboolean vmu_volume_read_block( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned char *out )
nkeynes@1034: {
nkeynes@1034:     if( pt >= vol->part_count || block >= vol->part[pt].block_count ) {
nkeynes@1034:         return FALSE;
nkeynes@1034:     }
nkeynes@1034: 
nkeynes@1034:     memcpy( out, VMU_BLOCK(vol,pt,block), VMU_BLOCK_SIZE );
nkeynes@1034:     return TRUE;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: gboolean vmu_volume_write_block( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned char *in )
nkeynes@1034: {
nkeynes@1034:     if( pt >= vol->part_count || block >= vol->part[pt].block_count ) {
nkeynes@1034:         return FALSE;
nkeynes@1034:     }
nkeynes@1034:     memcpy( VMU_BLOCK(vol,pt,block), in, VMU_BLOCK_SIZE );
nkeynes@1034:     vol->dirty = TRUE;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: gboolean vmu_volume_write_phase( vmu_volume_t vol, vmu_partnum_t pt, unsigned int block, unsigned int phase, unsigned char *in )
nkeynes@1034: {
nkeynes@1034:     if( pt >= vol->part_count || block >= vol->part[pt].block_count || phase >= 4 ) {
nkeynes@1034:         return FALSE;
nkeynes@1034:     }
nkeynes@1034:     memcpy( VMU_BLOCK(vol,pt,block) + (phase*128), in, VMU_BLOCK_SIZE/4 );
nkeynes@1034:     vol->dirty = TRUE;
nkeynes@1034: }
nkeynes@1034: 
nkeynes@1034: const struct vmu_volume_metadata *vmu_volume_get_metadata( vmu_volume_t vol, vmu_partnum_t partition )
nkeynes@1034: {
nkeynes@1034:     if( partition >= vol->part_count ) {
nkeynes@1034:         return NULL;
nkeynes@1034:     } else {
nkeynes@1034:         return &vol->part[partition].metadata;
nkeynes@1034:     }
nkeynes@1034: }