void _FAT_partition_writeFSinfo(PARTITION * partition)
{
if(partition->filesysType != FS_FAT32)
return;
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(partition->bytesPerSector);
if (!sectorBuffer) return;
memset(sectorBuffer, 0, partition->bytesPerSector);
// Read first sector of disc
if (!_FAT_disc_readSectors (partition->disc, partition->fsInfoSector, 1, sectorBuffer)) {
_FAT_mem_free(sectorBuffer);
return;
}
if(memcmp(sectorBuffer+FSIB_SIG1, FS_INFO_SIG1, 4) || memcmp(sectorBuffer+FSIB_SIG2, FS_INFO_SIG2, 4)) {
_FAT_mem_free(sectorBuffer);
return;
}
u32_to_u8array(sectorBuffer, FSIB_numberOfFreeCluster, partition->fat.numberFreeCluster);
u32_to_u8array(sectorBuffer, FSIB_numberLastAllocCluster, partition->fat.numberLastAllocCluster);
// Write first sector of disc
_FAT_disc_writeSectors (partition->disc, partition->fsInfoSector, 1, sectorBuffer);
_FAT_mem_free(sectorBuffer);
}
void _FAT_partition_readFSinfo(PARTITION * partition)
{
if(partition->filesysType != FS_FAT32)
return;
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(partition->bytesPerSector);
if (!sectorBuffer) return;
memset(sectorBuffer, 0, partition->bytesPerSector);
// Read first sector of disc
if (!_FAT_disc_readSectors (partition->disc, partition->fsInfoSector, 1, sectorBuffer)) {
_FAT_mem_free(sectorBuffer);
return;
}
if(memcmp(sectorBuffer+FSIB_SIG1, FS_INFO_SIG1, 4) != 0 ||
memcmp(sectorBuffer+FSIB_SIG2, FS_INFO_SIG2, 4) != 0 ||
u8array_to_u32(sectorBuffer, FSIB_numberOfFreeCluster) == 0)
{
//sector does not yet exist, create one!
_FAT_partition_createFSinfo(partition);
} else {
partition->fat.numberFreeCluster = u8array_to_u32(sectorBuffer, FSIB_numberOfFreeCluster);
if(partition->fat.numberFreeCluster == 0xffffffff) {
_FAT_updateFS_INFO(partition,sectorBuffer);
partition->fat.numberFreeCluster = u8array_to_u32(sectorBuffer, FSIB_numberOfFreeCluster);
}
partition->fat.numberLastAllocCluster = u8array_to_u32(sectorBuffer, FSIB_numberLastAllocCluster);
}
_FAT_mem_free(sectorBuffer);
}
void _FAT_partition_createFSinfo(PARTITION * partition)
{
if(partition->readOnly || partition->filesysType != FS_FAT32)
return;
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(partition->bytesPerSector);
if (!sectorBuffer) return;
memset(sectorBuffer, 0, partition->bytesPerSector);
int i;
for(i = 0; i < 4; ++i)
{
sectorBuffer[FSIB_SIG1+i] = FS_INFO_SIG1[i];
sectorBuffer[FSIB_SIG2+i] = FS_INFO_SIG2[i];
}
partition->fat.numberFreeCluster = _FAT_fat_freeClusterCount(partition);
u32_to_u8array(sectorBuffer, FSIB_numberOfFreeCluster, partition->fat.numberFreeCluster);
u32_to_u8array(sectorBuffer, FSIB_numberLastAllocCluster, partition->fat.numberLastAllocCluster);
sectorBuffer[FSIB_bootSig_55] = 0x55;
sectorBuffer[FSIB_bootSig_AA] = 0xAA;
_FAT_disc_writeSectors (partition->disc, partition->fsInfoSector, 1, sectorBuffer);
_FAT_mem_free(sectorBuffer);
}
sec_t FindFirstValidPartition(const DISC_INTERFACE* disc)
{
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(MAX_SECTOR_SIZE);
if (!sectorBuffer) return 0;
sec_t ret = FindFirstValidPartition_buf(disc, sectorBuffer);
_FAT_mem_free(sectorBuffer);
return ret;
}
PARTITION* _FAT_partition_constructor (const DISC_INTERFACE* disc, uint32_t cacheSize, uint32_t sectorsPerPage, sec_t startSector)
{
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(MAX_SECTOR_SIZE);
if (!sectorBuffer) return NULL;
PARTITION *ret = _FAT_partition_constructor_buf(disc, cacheSize,
sectorsPerPage, startSector, sectorBuffer);
_FAT_mem_free(sectorBuffer);
return ret;
}
CACHE* _FAT_cache_constructor (unsigned int numberOfPages, unsigned int sectorsPerPage, const DISC_INTERFACE* discInterface, sec_t endOfPartition, unsigned int bytesPerSector) {
CACHE* cache;
unsigned int i;
CACHE_ENTRY* cacheEntries;
if (numberOfPages < 2) {
numberOfPages = 2;
}
if (sectorsPerPage < 8) {
sectorsPerPage = 8;
}
cache = (CACHE*) _FAT_mem_allocate (sizeof(CACHE));
if (cache == NULL) {
return NULL;
}
cache->disc = discInterface;
cache->endOfPartition = endOfPartition;
cache->numberOfPages = numberOfPages;
cache->sectorsPerPage = sectorsPerPage;
cache->bytesPerSector = bytesPerSector;
cacheEntries = (CACHE_ENTRY*) _FAT_mem_allocate ( sizeof(CACHE_ENTRY) * numberOfPages);
if (cacheEntries == NULL) {
_FAT_mem_free (cache);
return NULL;
}
for (i = 0; i < numberOfPages; i++) {
cacheEntries[i].sector = CACHE_FREE;
cacheEntries[i].count = 0;
cacheEntries[i].last_access = 0;
cacheEntries[i].dirty = false;
cacheEntries[i].cache = (uint8_t*) _FAT_mem_align ( sectorsPerPage * bytesPerSector );
}
cache->cacheEntries = cacheEntries;
return cache;
}
void _FAT_partition_createFSinfo(PARTITION * partition)
{
if(partition->readOnly || partition->filesysType != FS_FAT32)
return;
uint8_t *sectorBuffer = (uint8_t*) _FAT_mem_align(partition->bytesPerSector);
if (!sectorBuffer) return;
memset(sectorBuffer, 0, partition->bytesPerSector);
int i;
for(i = 0; i < 4; ++i)
{
sectorBuffer[FSIB_SIG1+i] = FS_INFO_SIG1[i];
sectorBuffer[FSIB_SIG2+i] = FS_INFO_SIG2[i];
}
sectorBuffer[FSIB_bootSig_55] = 0x55;
sectorBuffer[FSIB_bootSig_AA] = 0xAA;
_FAT_updateFS_INFO(partition,sectorBuffer);
_FAT_mem_free(sectorBuffer);
}
