/*!
* \brief Unmounts the filesystem.
*
* This function brings filesystem on drive to consistent state by flushing
* all cached data and releases data structures.
*
* \param drive_ptr
*
* \return int Error code.
*/
int MFS_Unmount_drive_internal(
MFS_DRIVE_STRUCT_PTR drive_ptr)
{
int result = MFS_NO_ERROR;
#if !MFSCFG_READ_ONLY
if (drive_ptr->FAT_TYPE == MFS_FAT32)
{
if (!MFS_is_read_only(drive_ptr))
{
FILESYSTEM_INFO_DISK_PTR fsinfo_ptr;
result = MFS_sector_map(drive_ptr, drive_ptr->FS_INFO, (void **)&fsinfo_ptr, MFS_MAP_MODE_OVERWRITE, 0);
if (result == MFS_NO_ERROR)
{
mqx_htodl(fsinfo_ptr->LEAD_SIG, FSI_LEADSIG);
mqx_htodl(fsinfo_ptr->STRUCT_SIG, FSI_STRUCTSIG);
mqx_htodl(fsinfo_ptr->FREE_COUNT, drive_ptr->FREE_COUNT);
mqx_htodl(fsinfo_ptr->NEXT_FREE, drive_ptr->NEXT_FREE_CLUSTER);
mqx_htodl(fsinfo_ptr->TRAIL_SIG, FSI_TRAILSIG);
result = MFS_sector_unmap(drive_ptr, drive_ptr->FS_INFO, 1);
}
}
}
#endif
return result;
}
void *MFS_Create_file
(
MFS_DRIVE_STRUCT_PTR drive_ptr,
unsigned char attr, /*[IN] attribute for created file*/
char *pathname, /*[IN] directory and filename of the file to be created */
_mfs_error_ptr error_ptr /*[IN/OUT] error code is written to this address */
)
{
MFS_HANDLE_PTR handle;
MFS_HANDLE_PTR next_handle;
MFS_DIR_ENTRY_PTR dir_entry_ptr;
TIME_STRUCT time;
DATE_STRUCT clk_time;
uint32_t dir_cluster;
uint32_t dir_index;
char access;
_mfs_error error_code, saved_code = 0;
if ( (pathname == NULL) || (*pathname == '\0') )
{
*error_ptr = MFS_INVALID_PARAMETER;
return( NULL );
}
#if MFSCFG_READ_ONLY_CHECK
if (MFS_is_read_only (drive_ptr))
{
*error_ptr = MFS_DISK_IS_WRITE_PROTECTED;
return NULL;
}
#endif
error_code = MFS_lock_dos_disk( drive_ptr );
if ( error_code != MFS_NO_ERROR )
{
*error_ptr = error_code;
return( NULL );
}
handle = NULL;
attr &= (MFS_ATTR_READ_ONLY | MFS_ATTR_HIDDEN_FILE | MFS_ATTR_SYSTEM_FILE | MFS_ATTR_ARCHIVE | MFS_ATTR_VOLUME_NAME);
attr |= MFS_ATTR_ARCHIVE;
access = (attr & MFS_ATTR_READ_ONLY) ? MFS_ACCESS_READ_ONLY : MFS_ACCESS_READ_WRITE;
dir_entry_ptr = MFS_Create_entry_slave(drive_ptr, attr, pathname, &dir_cluster, &dir_index, &error_code, TRUE);
if ( (dir_entry_ptr != NULL) && !(attr & MFS_ATTR_VOLUME_NAME) )
{
handle = MFS_Get_handle(drive_ptr,dir_entry_ptr);
if ( handle != NULL )
{
handle->DIR_CLUSTER = dir_cluster;
handle->DIR_INDEX = dir_index;
handle->ACCESS = access;
handle->CURRENT_CLUSTER = 0;
handle->PREVIOUS_CLUSTER = 0;
/*
** If file exists, overwrite and set size to 0
*/
if ( error_code == MFS_FILE_EXISTS )
{
_time_get(&time);
_time_to_date(&time, &clk_time);
NORMALIZE_DATE(&clk_time);
saved_code = MFS_Release_chain(drive_ptr, clustoh(handle->DIR_ENTRY.HFIRST_CLUSTER, handle->DIR_ENTRY.LFIRST_CLUSTER));
if ( saved_code == MFS_NO_ERROR || saved_code == MFS_LOST_CHAIN )
{
clustod(handle->DIR_ENTRY.HFIRST_CLUSTER, handle->DIR_ENTRY.LFIRST_CLUSTER, 0);
mqx_htodl(handle->DIR_ENTRY.FILE_SIZE, 0L);
mqx_htodc(handle->DIR_ENTRY.ATTRIBUTE, attr);
mqx_htods(handle->DIR_ENTRY.TIME, PACK_TIME(clk_time));
mqx_htods(handle->DIR_ENTRY.DATE, PACK_DATE(clk_time));
error_code = MFS_Update_entry(drive_ptr, handle);
/*
** If the same file is already open, mark it as 'freshly
** truncated' so reads and writes don't clobber any data.
*/
if ( error_code == MFS_NO_ERROR )
{
next_handle = (MFS_HANDLE_PTR) _queue_head(&drive_ptr->HANDLE_LIST);
while ( next_handle )
{
if ( next_handle->DIR_CLUSTER == dir_cluster && next_handle->DIR_INDEX == dir_index )
{
next_handle->CURRENT_CLUSTER = 0;
next_handle->PREVIOUS_CLUSTER = 0;
}
next_handle = (MFS_HANDLE_PTR) _queue_next(&drive_ptr->HANDLE_LIST, (QUEUE_ELEMENT_STRUCT_PTR) next_handle);
}
}
}
}
/*
** No need to update the disk image if we didn't change anything.
*/
if ( (mqx_dtohc(handle->DIR_ENTRY.ATTRIBUTE) != attr) && (error_code == MFS_NO_ERROR) )
{
mqx_htodc(handle->DIR_ENTRY.ATTRIBUTE, attr);
error_code = MFS_Update_entry(drive_ptr, handle);
}
}
else
{
error_code = MFS_INSUFFICIENT_MEMORY;
}
}
MFS_unlock(drive_ptr,FALSE);
if ( error_code == MFS_NO_ERROR && saved_code == MFS_LOST_CHAIN )
{
*error_ptr = saved_code;
}
else
{
*error_ptr = error_code;
}
return((void *)handle);
}
/*!
* \brief Used to set the MFS drive parameters for a unit.
*
* This function assumes that the boot sector of the drive is stored in
* the drive's sector buffer. This function is called after MFS is
* initialized, or after the drive has been formatted.
*
* NOTE: It is assumed that the drive is locked by the calling function.
*
* \param drive_ptr
*
* \return uint32_t Error code.
*/
uint32_t MFS_Mount_drive_internal(
MFS_DRIVE_STRUCT_PTR drive_ptr)
{
BIOS_PARAM_STRUCT_DISK_PTR bpb_ptr;
BIOS_PARAM32_STRUCT_DISK_PTR bpb32_ptr;
FILESYSTEM_INFO_DISK_PTR fsinfo_ptr;
uint32_t reserved_sectors;
uint32_t root_dir_sectors;
uint32_t data_sectors;
uint32_t cluster_count;
uint32_t bpb_sector_size;
uint32_t bpb_sector_mult;
int error_code;
int result = MFS_NO_ERROR;
uint8_t *boot_sector;
drive_ptr->DOS_DISK = false;
error_code = MFS_sector_cache_invalidate(drive_ptr, 0, 0);
if (error_code != MFS_NO_ERROR)
{
return error_code;
}
error_code = MFS_sector_map(drive_ptr, BOOT_SECTOR, (void **)&boot_sector, MFS_MAP_MODE_READONLY, 0);
if (error_code != MFS_NO_ERROR)
{
return error_code;
}
/*
** Extract the drive parameters (BIOS Parameter Block) from the BOOT Record.
*/
bpb_ptr = (BIOS_PARAM_STRUCT_DISK_PTR)boot_sector;
bpb32_ptr = (BIOS_PARAM32_STRUCT_DISK_PTR)(boot_sector + sizeof(BIOS_PARAM_STRUCT_DISK));
/*
** Next, check to see that the BOOT record is that of a DOS disk. If not,
** the drive will have to be formatted by the upper layer before the drive
** can be 'mounted'.
*/
if ((boot_sector[0] != MFS_DOS30_JMP) && (boot_sector[0] != MFS_DOS30_B))
{
result = MFS_NOT_A_DOS_DISK;
}
if (result == MFS_NO_ERROR)
{
/*
** Always use storage device sector size.
** If BPB sector size is larger, then recalculate other parameters accordingly.
** In any case, BPB sector size has to be multiple of device sector size, the code explicitly checks this.
*/
bpb_sector_size = mqx_dtohs(bpb_ptr->SECTOR_SIZE);
if (bpb_sector_size % drive_ptr->SECTOR_SIZE)
{
result = MFS_NOT_A_DOS_DISK;
}
}
if (result == MFS_NO_ERROR)
{
/* Sector values from BPB are to be multiplied by this factor */
bpb_sector_mult = bpb_sector_size / drive_ptr->SECTOR_SIZE;
reserved_sectors = mqx_dtohs(bpb_ptr->RESERVED_SECTORS) * bpb_sector_mult;
drive_ptr->SECTORS_PER_CLUSTER = mqx_dtohc(bpb_ptr->SECTORS_PER_CLUSTER) * bpb_sector_mult;
drive_ptr->CLUSTER_POWER_SECTORS = ilog2(drive_ptr->SECTORS_PER_CLUSTER);
drive_ptr->CLUSTER_POWER_BYTES = drive_ptr->SECTOR_POWER + drive_ptr->CLUSTER_POWER_SECTORS;
drive_ptr->CLUSTER_SIZE_BYTES = drive_ptr->SECTOR_SIZE * drive_ptr->SECTORS_PER_CLUSTER;
drive_ptr->NUMBER_OF_FAT = mqx_dtohc(bpb_ptr->NUMBER_OF_FAT);
drive_ptr->ROOT_ENTRIES = mqx_dtohs(bpb_ptr->ROOT_ENTRIES);
drive_ptr->SECTORS_PER_FAT = mqx_dtohs(bpb_ptr->SECTORS_PER_FAT);
if (drive_ptr->SECTORS_PER_FAT == 0)
{
drive_ptr->SECTORS_PER_FAT = mqx_dtohl(bpb32_ptr->FAT_SIZE);
}
drive_ptr->SECTORS_PER_FAT *= bpb_sector_mult;
drive_ptr->MEGA_SECTORS = mqx_dtohs(bpb_ptr->NUMBER_SECTORS);
if (drive_ptr->MEGA_SECTORS == 0)
{
drive_ptr->MEGA_SECTORS = mqx_dtohl(bpb_ptr->MEGA_SECTORS);
}
drive_ptr->MEGA_SECTORS *= bpb_sector_mult;
/* Determine FAT type by calculating the count of clusters on disk */
drive_ptr->ENTRIES_PER_SECTOR = drive_ptr->SECTOR_SIZE / sizeof(DIR_ENTRY_DISK);
root_dir_sectors = drive_ptr->ROOT_ENTRIES / drive_ptr->ENTRIES_PER_SECTOR;
data_sectors = drive_ptr->MEGA_SECTORS - reserved_sectors - root_dir_sectors - (drive_ptr->NUMBER_OF_FAT * drive_ptr->SECTORS_PER_FAT);
cluster_count = data_sectors / drive_ptr->SECTORS_PER_CLUSTER;
/* Now we have cluster count, so we can determine FAT type */
if (cluster_count < 4085)
{
drive_ptr->FAT_TYPE = MFS_FAT12;
}
else if (cluster_count < 65525)
{
drive_ptr->FAT_TYPE = MFS_FAT16;
}
else
{
drive_ptr->FAT_TYPE = MFS_FAT32;
}
drive_ptr->CLUSTER_SIZE_BYTES = drive_ptr->SECTOR_SIZE * drive_ptr->SECTORS_PER_CLUSTER;
drive_ptr->CLUSTER_POWER_BYTES = drive_ptr->SECTOR_POWER + drive_ptr->CLUSTER_POWER_SECTORS;
drive_ptr->FREE_COUNT = FSI_UNKNOWN; /* This is the unknown value */
drive_ptr->NEXT_FREE_CLUSTER = FSI_UNKNOWN; /* MFS will calculate it later */
drive_ptr->FAT_START_SECTOR = reserved_sectors;
drive_ptr->DATA_START_SECTOR = drive_ptr->FAT_START_SECTOR + (drive_ptr->SECTORS_PER_FAT * drive_ptr->NUMBER_OF_FAT) + root_dir_sectors;
if (drive_ptr->FAT_TYPE != MFS_FAT32)
{
/* FAT12 or FAT16 */
drive_ptr->ROOT_START_SECTOR = drive_ptr->FAT_START_SECTOR + (drive_ptr->SECTORS_PER_FAT * drive_ptr->NUMBER_OF_FAT);
drive_ptr->ROOT_CLUSTER = 0;
MFS_chain_forge(drive_ptr, &drive_ptr->ROOT_CHAIN, drive_ptr->ROOT_START_SECTOR, root_dir_sectors);
}
else if (mqx_dtohs(bpb32_ptr->FS_VER) > MFS_FAT32_VER)
{
/* Unsupported FAT32 level */
result = MFS_ERROR_UNKNOWN_FS_VERSION;
}
else
{
/* Supported FAT32 */
drive_ptr->ROOT_CLUSTER = mqx_dtohl(bpb32_ptr->ROOT_CLUSTER);
drive_ptr->ROOT_START_SECTOR = 0;
MFS_chain_init(drive_ptr, &drive_ptr->ROOT_CHAIN, drive_ptr->ROOT_CLUSTER);
drive_ptr->FS_INFO = mqx_dtohs(bpb32_ptr->FS_INFO);
}
}
error_code = MFS_sector_unmap(drive_ptr, BOOT_SECTOR, 0);
if (result == MFS_NO_ERROR)
{
result = error_code;
}
if (result != MFS_NO_ERROR)
{
return result;
}
if (drive_ptr->FAT_TYPE == MFS_FAT32)
{
/*
** Reset the FSInfo->Free_Count and the FSInfo->Next_Free to
** unknown (0xFFFFFFFF). MFS uses it's own internal version of these
** fields. If Windows uses the same disk, it will recalculate the
** correct fields the first time it mounts the drive.
*/
error_code = MFS_sector_map(drive_ptr, drive_ptr->FS_INFO, (void **)&fsinfo_ptr, MFS_is_read_only(drive_ptr) ? MFS_MAP_MODE_READONLY : MFS_MAP_MODE_MODIFY, 0);
if (error_code == MFS_NO_ERROR)
{
if ((mqx_dtohl(fsinfo_ptr->LEAD_SIG) == FSI_LEADSIG) && (mqx_dtohl(fsinfo_ptr->STRUCT_SIG) == FSI_STRUCTSIG) &&
(mqx_dtohl(fsinfo_ptr->TRAIL_SIG) == FSI_TRAILSIG))
{
drive_ptr->FREE_COUNT = mqx_dtohl(fsinfo_ptr->FREE_COUNT);
drive_ptr->NEXT_FREE_CLUSTER = mqx_dtohl(fsinfo_ptr->NEXT_FREE);
}
if (!MFS_is_read_only(drive_ptr))
{
mqx_htodl(fsinfo_ptr->LEAD_SIG, FSI_LEADSIG);
mqx_htodl(fsinfo_ptr->STRUCT_SIG, FSI_STRUCTSIG);
mqx_htodl(fsinfo_ptr->FREE_COUNT, FSI_UNKNOWN); /* compute it */
mqx_htodl(fsinfo_ptr->NEXT_FREE, FSI_UNKNOWN); /* compute it */
mqx_htodl(fsinfo_ptr->TRAIL_SIG, FSI_TRAILSIG);
}
error_code = MFS_sector_unmap(drive_ptr, drive_ptr->FS_INFO, !MFS_is_read_only(drive_ptr));
}
if (result == MFS_NO_ERROR)
{
result = error_code;
}
}
drive_ptr->LAST_CLUSTER = (drive_ptr->MEGA_SECTORS - drive_ptr->DATA_START_SECTOR) / drive_ptr->SECTORS_PER_CLUSTER + 1;
drive_ptr->CURRENT_DIR[0] = '\\'; /* Root dir */
drive_ptr->CURRENT_DIR[1] = '\0';
drive_ptr->CUR_DIR_CLUSTER = drive_ptr->ROOT_CLUSTER;
drive_ptr->CUR_DIR_CHAIN_PTR = &drive_ptr->ROOT_CHAIN;
if (result == MFS_NO_ERROR)
{
drive_ptr->DOS_DISK = true;
}
return result;
}
