/* fat_file_read --
* Read 'count' bytes from 'start' position from fat-file. This
* interface hides the architecture of fat-file, represents it as
* linear file
*
* PARAMETERS:
* mt_entry - mount table entry
* fat_fd - fat-file descriptor
* start - offset in fat-file (in bytes) to read from
* count - count of bytes to read
* buf - buffer provided by user
*
* RETURNS:
* the number of bytes read on success, or -1 if error occured (errno
* set appropriately)
*/
ssize_t
fat_file_read(
rtems_filesystem_mount_table_entry_t *mt_entry,
fat_file_fd_t *fat_fd,
uint32_t start,
uint32_t count,
uint8_t *buf
)
{
int rc = RC_OK;
ssize_t ret = 0;
fat_fs_info_t *fs_info = mt_entry->fs_info;
uint32_t cmpltd = 0;
uint32_t cur_cln = 0;
uint32_t cl_start = 0;
uint32_t save_cln = 0;
uint32_t ofs = 0;
uint32_t save_ofs;
uint32_t sec = 0;
uint32_t byte = 0;
uint32_t c = 0;
/* it couldn't be removed - otherwise cache update will be broken */
if (count == 0)
return cmpltd;
/*
* >= because start is offset and computed from 0 and file_size
* computed from 1
*/
if ( start >= fat_fd->fat_file_size )
return FAT_EOF;
if ((count > fat_fd->fat_file_size) ||
(start > fat_fd->fat_file_size - count))
count = fat_fd->fat_file_size - start;
if ((FAT_FD_OF_ROOT_DIR(fat_fd)) &&
(fs_info->vol.type & (FAT_FAT12 | FAT_FAT16)))
{
sec = fat_cluster_num_to_sector_num(mt_entry, fat_fd->cln);
sec += (start >> fs_info->vol.sec_log2);
byte = start & (fs_info->vol.bps - 1);
ret = _fat_block_read(mt_entry, sec, byte, count, buf);
if ( ret < 0 )
return -1;
return ret;
}
/* fat_cluster_write --
* wrapper for writting a whole cluster at once
*
* PARAMETERS:
* mt_entry - mount table entry
* cln - number of cluster to write
* buff - buffer provided by user
*
* RETURNS:
* bytes written on success, or -1 if error occured
* and errno set appropriately
*/
ssize_t
fat_cluster_write(
rtems_filesystem_mount_table_entry_t *mt_entry,
uint32_t cln,
const void *buff
)
{
fat_fs_info_t *fs_info = mt_entry->fs_info;
uint32_t fsec = 0;
fsec = fat_cluster_num_to_sector_num(mt_entry, cln);
return _fat_block_write(mt_entry, fsec, 0,
fs_info->vol.spc << fs_info->vol.sec_log2, buff);
}
/* msdos_set_first_char4file_name --
* Write first character of the name of the file to the disk (to
* corresponded 32bytes slot)
*
* PARAMETERS:
* mt_entry - mount table entry
* cl - number of cluster
* ofs - offset inside cluster
* fchar - character to set up
*
* RETURNS:
* RC_OK on success, or -1 if error occured (errno set apropriately)
*
*/
int
msdos_set_first_char4file_name(
rtems_filesystem_mount_table_entry_t *mt_entry,
uint32_t cl,
uint32_t ofs,
unsigned char fchar
)
{
ssize_t ret = 0;
msdos_fs_info_t *fs_info = mt_entry->fs_info;
uint32_t sec = 0;
uint32_t byte = 0;
sec = fat_cluster_num_to_sector_num(mt_entry, cl);
sec += (ofs >> fs_info->fat.vol.sec_log2);
byte = (ofs & (fs_info->fat.vol.bps - 1));
ret = _fat_block_write(mt_entry, sec, byte + MSDOS_FILE_NAME_OFFSET, 1,
&fchar);
if ( ret < 0)
return -1;
return RC_OK;
}
/* msdos_set_file size --
* Write file size of the file to the disk (to corresponded 32bytes slot)
*
* PARAMETERS:
* mt_entry - mount table entry
* fat_fd - fat-file descriptor
*
* RETURNS:
* RC_OK on success, or -1 if error occured (errno set apropriately).
*
*/
int
msdos_set_file_size(
rtems_filesystem_mount_table_entry_t *mt_entry,
fat_file_fd_t *fat_fd
)
{
ssize_t ret = 0;
msdos_fs_info_t *fs_info = mt_entry->fs_info;
uint32_t le_new_length = 0;
uint32_t sec = 0;
uint32_t byte = 0;
sec = fat_cluster_num_to_sector_num(mt_entry, fat_fd->info_cln);
sec += (fat_fd->info_ofs >> fs_info->fat.vol.sec_log2);
byte = (fat_fd->info_ofs & (fs_info->fat.vol.bps - 1));
le_new_length = CT_LE_L((fat_fd->fat_file_size));
ret = _fat_block_write(mt_entry, sec, byte + MSDOS_FILE_SIZE_OFFSET, 4,
(char *)(&le_new_length));
if ( ret < 0 )
return -1;
return RC_OK;
}
/* msdos_set_first_cluster_num --
* Write number of first cluster of the file to the disk (to corresponded
* 32bytes slot)
*
* PARAMETERS:
* mt_entry - mount table entry
* fat_fd - fat-file descriptor
*
* RETURNS:
* RC_OK on success, or -1 if error occured
*
*/
int
msdos_set_first_cluster_num(
rtems_filesystem_mount_table_entry_t *mt_entry,
fat_file_fd_t *fat_fd
)
{
ssize_t ret1 = 0, ret2 = 0;
msdos_fs_info_t *fs_info = mt_entry->fs_info;
uint32_t new_cln = fat_fd->cln;
uint16_t le_cl_low = 0;
uint16_t le_cl_hi = 0;
uint32_t sec = 0;
uint32_t byte = 0;
/*
* calculate input for _fat_block_write: convert (cluster num, offset) to
* (sector num, new offset)
*/
sec = fat_cluster_num_to_sector_num(mt_entry, fat_fd->info_cln);
sec += (fat_fd->info_ofs >> fs_info->fat.vol.sec_log2);
/* byte from points to start of 32bytes structure */
byte = fat_fd->info_ofs & (fs_info->fat.vol.bps - 1);
le_cl_low = CT_LE_W((uint16_t )(new_cln & 0x0000FFFF));
ret1 = _fat_block_write(mt_entry, sec,
byte + MSDOS_FIRST_CLUSTER_LOW_OFFSET, 2,
(char *)(&le_cl_low));
le_cl_hi = CT_LE_W((uint16_t )((new_cln & 0xFFFF0000) >> 16));
ret2 = _fat_block_write(mt_entry, sec,
byte + MSDOS_FIRST_CLUSTER_HI_OFFSET, 2,
(char *)(&le_cl_hi));
if ( (ret1 < 0) || (ret2 < 0) )
return -1;
return RC_OK;
}
/* msdos_set_dir_wrt_time_and_date --
* Write last write date and time for a file to the disk (to corresponded
* 32bytes node)
*
* PARAMETERS:
* mt_entry - mount table entry
* fat_fd - fat-file descriptor
*
* RETURNS:
* RC_OK on success, or -1 if error occured (errno set apropriately).
*
*/
int
msdos_set_dir_wrt_time_and_date(
rtems_filesystem_mount_table_entry_t *mt_entry,
fat_file_fd_t *fat_fd
)
{
ssize_t ret1 = 0, ret2 = 0;
msdos_fs_info_t *fs_info = mt_entry->fs_info;
unsigned short time_val;
unsigned short date;
uint32_t sec = 0;
uint32_t byte = 0;
msdos_date_unix2dos(fat_fd->mtime, &time_val, &date);
/*
* calculate input for _fat_block_write: convert (cluster num, offset) to
* (sector num, new offset)
*/
sec = fat_cluster_num_to_sector_num(mt_entry, fat_fd->info_cln);
sec += (fat_fd->info_ofs >> fs_info->fat.vol.sec_log2);
/* byte points to start of 32bytes structure */
byte = fat_fd->info_ofs & (fs_info->fat.vol.bps - 1);
time_val = CT_LE_W(time_val);
ret1 = _fat_block_write(mt_entry, sec, byte + MSDOS_FILE_WTIME_OFFSET,
2, (char *)(&time_val));
date = CT_LE_W(date);
ret2 = _fat_block_write(mt_entry, sec, byte + MSDOS_FILE_WDATE_OFFSET,
2, (char *)(&date));
if ( (ret1 < 0) || (ret2 < 0) )
return -1;
return RC_OK;
}
/* msdos_creat_node --
* Create a new node. Determine if the name is a long name. If long we to
* scan the directory to create a short entry.
*
*
* If a new node is file, FAT 32 Bytes Directory
* Entry Structure is initialized, free space is found in parent
* directory and structure is written to the disk. In case of directory,
* all above steps present and also new cluster is allocated for a
* new directory and dot and dotdot nodes are created in alloceted cluster.
*
* PARAMETERS:
* parent_loc - parent (directory we are going to create node in)
* type - new node type (file or directory)
* name - new node name
* mode - mode
* link_info - fs_info of existing node for a pseudo "hard-link"
* (see msdos_file.c, msdos_link for documentation)
*
* RETURNS:
* RC_OK on success, or -1 if error occured (errno set appropriately).
*
*/
int
msdos_creat_node(const rtems_filesystem_location_info_t *parent_loc,
fat_file_type_t type,
const char *name,
int name_len,
mode_t mode,
const fat_file_fd_t *link_fd)
{
int rc = RC_OK;
ssize_t ret = 0;
msdos_fs_info_t *fs_info = parent_loc->mt_entry->fs_info;
fat_file_fd_t *parent_fat_fd = parent_loc->node_access;
fat_file_fd_t *fat_fd = NULL;
time_t now;
uint16_t time_val = 0;
uint16_t date = 0;
fat_dir_pos_t dir_pos;
msdos_name_type_t name_type;
char short_node[MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE];
char dot_dotdot[MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE * 2];
char link_node[MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE];
uint32_t sec = 0;
uint32_t byte = 0;
fat_dir_pos_init(&dir_pos);
memset(short_node, 0, MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE);
memset(dot_dotdot, 0, MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE * 2);
if (name_len > MSDOS_NAME_MAX_LFN_WITH_DOT) {
rtems_set_errno_and_return_minus_one(ENAMETOOLONG);
}
name_type = msdos_long_to_short (fs_info->converter,
name, name_len,
MSDOS_DIR_NAME(short_node),
MSDOS_NAME_MAX);
if (name_type == MSDOS_NAME_INVALID) {
rtems_set_errno_and_return_minus_one(EINVAL);
}
/* fill reserved field */
*MSDOS_DIR_NT_RES(short_node) = MSDOS_RES_NT_VALUE;
/* set up last write date and time */
now = time(NULL);
fat_file_set_ctime_mtime(parent_fat_fd, now);
msdos_date_unix2dos(now, &date, &time_val);
*MSDOS_DIR_CRT_TIME(short_node) = CT_LE_W(time_val);
*MSDOS_DIR_CRT_DATE(short_node) = CT_LE_W(date);
*MSDOS_DIR_WRITE_TIME(short_node) = CT_LE_W(time_val);
*MSDOS_DIR_WRITE_DATE(short_node) = CT_LE_W(date);
*MSDOS_DIR_LAST_ACCESS_DATE(short_node) = CT_LE_W(date);
/* initialize directory/file size */
*MSDOS_DIR_FILE_SIZE(short_node) = MSDOS_INIT_DIR_SIZE;
if (type == FAT_DIRECTORY) {
*MSDOS_DIR_ATTR(short_node) |= MSDOS_ATTR_DIRECTORY;
}
else if (type == FAT_HARD_LINK) {
/*
* when we establish a (temporary) hard link,
* we must copy some information from the original
* node to the newly created
*/
/*
* read the original directory entry
*/
sec = fat_cluster_num_to_sector_num(&fs_info->fat,
link_fd->dir_pos.sname.cln);
sec += (link_fd->dir_pos.sname.ofs >> fs_info->fat.vol.sec_log2);
byte = (link_fd->dir_pos.sname.ofs & (fs_info->fat.vol.bps - 1));
ret = _fat_block_read(&fs_info->fat,
sec, byte, MSDOS_DIRECTORY_ENTRY_STRUCT_SIZE,
link_node);
if (ret < 0) {
return -1;
}
/*
* copy various attributes
*/
*MSDOS_DIR_ATTR(short_node) =*MSDOS_DIR_ATTR(link_node);
*MSDOS_DIR_CRT_TIME_TENTH(short_node)=*MSDOS_DIR_CRT_TIME_TENTH(link_node);
*MSDOS_DIR_CRT_TIME(short_node) =*MSDOS_DIR_CRT_TIME(link_node);
*MSDOS_DIR_CRT_DATE(short_node) =*MSDOS_DIR_CRT_DATE(link_node);
/*
* copy/set "file size", "first cluster"
*/
*MSDOS_DIR_FILE_SIZE(short_node) =*MSDOS_DIR_FILE_SIZE(link_node);
*MSDOS_DIR_FIRST_CLUSTER_LOW(short_node) =
*MSDOS_DIR_FIRST_CLUSTER_LOW(link_node);
*MSDOS_DIR_FIRST_CLUSTER_HI(short_node) =
*MSDOS_DIR_FIRST_CLUSTER_HI(link_node);
/*
* set "archive bit" due to changes
*/
*MSDOS_DIR_ATTR(short_node) |= MSDOS_ATTR_ARCHIVE;
}
