MFS_DIR_ENTRY_PTR MFS_Find_directory_entry
(
MFS_DRIVE_STRUCT_PTR drive_ptr, /*[IN] drive context */
char *file_ptr, /*[IN] specific name to search for, if NULL then first dir entry */
uint32_t *start_cluster_ptr, /*[IN] start searching in this cluster
**[OUT] set to the cluster number in which search was satisfied */
uint32_t *dir_index_ptr, /*[IN] start searching at this directory entry
**[OUT] if entry is found the index of the next entry is returned */
uint32_t *prev_cluster_ptr, /* [IN] set to the cluster number previous to start_cluster
** [OUT] set to the cluster number previous to *dir_cluster_ptr */
unsigned char attribute, /*[IN] search attribute, as per Find_first_file */
_mfs_error_ptr error_ptr /* The pointer carries the error infomation */
)
{
MFS_DIR_ENTRY_PTR dir_entry_ptr = NULL;
char *lfn_ptr = NULL;
bool found;
bool lfn_flag;
bool maybe = FALSE;
bool found_lfn = FALSE;
uint32_t current_cluster, current_index;
_mfs_error error_code;
uint32_t lfn_len = 0;
uint16_t entries_per_sector;
uint16_t k, i;
char lfn_entry[40]; /* LFN entry contains up to 13 UTF16 characters, up to 40 bytes including null term are necessary when encoded using UTF8 */
char fs_file[SFILENAME_SIZE + 1];
uint32_t prev_cluster = *prev_cluster_ptr;
uint32_t dirname = 0;
error_code = MFS_NO_ERROR;
entries_per_sector = drive_ptr->ENTRIES_PER_SECTOR;
current_cluster = *start_cluster_ptr;
current_index = *dir_index_ptr;
found = FALSE;
lfn_flag = FALSE;
/* If the name is a LFN, it will be treated differently */
if ( file_ptr && *file_ptr && !MFS_Dirname_valid(file_ptr) )
{
lfn_flag = TRUE;
lfn_len = _strnlen(file_ptr, PATHNAME_SIZE);
/* Set pointer just behind the end of the filename */
lfn_ptr = file_ptr + lfn_len;
maybe = TRUE;
found_lfn = FALSE;
/* We also need special treatement for a directory name */
if ( attribute == (ATTR_EXCLUSIVE | MFS_ATTR_DIR_NAME) )
{
attribute = MFS_ATTR_LFN;
dirname = 1;
}
}
else if ( file_ptr && *file_ptr )
{
MFS_Expand_dotfile(file_ptr, fs_file);
}
/*
** Search in all clusters within this directory
*/
do
{
/*
** Search in all sectors within this cluster
*/
for ( k = (uint16_t) INDEX_TO_SECTOR(current_index);
((current_cluster == 0) || (k < drive_ptr->BPB.SECTORS_PER_CLUSTER)) && found == FALSE && current_cluster != CLUSTER_EOF;
k++ )
{
dir_entry_ptr = MFS_Read_directory_sector(drive_ptr,current_cluster, k, &error_code);
if ( dir_entry_ptr == NULL )
{
break;
}
/*
** Search in all entries within this sector
*/
for ( i = (uint16_t) INDEX_TO_OFFSET(current_index), dir_entry_ptr += i ; i < entries_per_sector && found == FALSE; i++ )
{
if ( *dir_entry_ptr->NAME == '\0' ) /* if NEVER USED entry */
{
if ( file_ptr ) /* If not NULL */
{
if ( !*file_ptr ) /* but "" */
{
/* we found it */
found = TRUE;
break;
}
}
return(NULL); /* Anyway, stop here-never used entry */
/* if the entry is relevant at all */
}
else if ( (unsigned char) *dir_entry_ptr->NAME == MFS_DEL_FILE )
{
/* If DELETED */
if ( file_ptr ) /* If not NULL */
{
if ( !*file_ptr ) /* but "" */
{
found = TRUE; /* we found it */
break;
}
}
}
else /* If REGULAR ENTRY */
{
if ( file_ptr == NULL || *file_ptr )
{
if ( MFS_Attribute_match(mqx_dtohc(dir_entry_ptr->ATTRIBUTE),
attribute) == TRUE )
{
if ( !file_ptr )
{
found = TRUE;
break;
}
else if ( lfn_flag ) /* Searching for a long name */
{
if ( found_lfn )
{
found = TRUE;
break;
}
if ( !MFS_Attribute_match(mqx_dtohc(dir_entry_ptr->ATTRIBUTE),
MFS_ATTR_LFN) )
{
maybe = TRUE; /* Reset maybe */
dir_entry_ptr++;
current_index++;
continue; /* Not an LFN entry, skip it */
}
if ( !maybe )
{
dir_entry_ptr++;
current_index++;
continue;
}
int chunk_len;
chunk_len = MFS_lfn_extract((MFS_LNAME_ENTRY_PTR)dir_entry_ptr, lfn_entry);
if(lfn_ptr >= (file_ptr + chunk_len))
{
lfn_ptr -= chunk_len;
if ( strncmp(lfn_entry, lfn_ptr, chunk_len) )
{
lfn_ptr = file_ptr + lfn_len; /* reset ptr */
maybe = FALSE;
dir_entry_ptr++;
current_index++;
continue; /* Strings don't match */
}
if ( lfn_ptr == file_ptr )
{
found_lfn = TRUE;
if ( dirname )
{
attribute = ATTR_EXCLUSIVE | MFS_ATTR_DIR_NAME;
}
}
}
else
{
maybe = FALSE;
lfn_ptr = file_ptr + lfn_len; /* reset ptr */
}
}
else /* Searching for a short name */
{
found = MFS_Wildcard_match(fs_file, dir_entry_ptr->NAME);
}
}
else
{
if ( lfn_flag )
{
attribute = MFS_ATTR_LFN;
lfn_ptr = file_ptr + lfn_len; /* reset ptr */
maybe = TRUE;
found_lfn = FALSE;
}
}
}
}
if ( found == FALSE )
{
dir_entry_ptr++;
current_index++;
}
}
}
if ( found == FALSE )
{
error_code = MFS_Increment_dir_index(drive_ptr, ¤t_cluster, ¤t_index, &prev_cluster);
if ( error_code )
{
break;
}
}
} while ( found == FALSE && dir_entry_ptr && current_cluster != CLUSTER_EOF && current_cluster != CLUSTER_INVALID );
if ( found == FALSE )
{
dir_entry_ptr = NULL;
}
else
{
*start_cluster_ptr = current_cluster;
*prev_cluster_ptr = prev_cluster;
*dir_index_ptr = current_index;
}
if ( error_ptr )
{
*error_ptr = error_code;
}
return(dir_entry_ptr);
}
_mfs_error MFS_Increment_dir_index
(
MFS_DRIVE_STRUCT_PTR drive_ptr, /*[IN] the drive on which to operate */
uint_32_ptr cluster_ptr, /*[IN/OUT] the initial/next cluster # */
uint_32_ptr index_ptr, /*[IN/OUT] the initial/next index */
uint_32_ptr prev_cluster_ptr /*[IN/OUT] the prev cluster # */
)
{
uint_32 index;
uint_32 cluster;
_mfs_error error_code;
error_code = MFS_NO_ERROR;
index = *index_ptr;
cluster = *cluster_ptr;
index++;
if ( !(index & (drive_ptr->ENTRIES_PER_SECTOR-1)) )
{
/*
** if the index count LSB's wrapped to 0 (new sector)
*/
if ( cluster != 0 )
{
if ( INDEX_TO_SECTOR (index) >= drive_ptr->BPB.SECTORS_PER_CLUSTER )
{
/*
** If we are over the size of a cluster
*/
error_code = MFS_get_cluster_from_fat(drive_ptr,cluster, &cluster);
if ( error_code == MFS_NO_ERROR )
{
index = 0;
}
}
}
else
{
if ( index >= drive_ptr->BPB.ROOT_ENTRIES )
{
index = 0;
cluster = CLUSTER_INVALID;
}
}
}
if ( (cluster != *cluster_ptr) && (cluster != CLUSTER_INVALID) )
{
if ( prev_cluster_ptr != NULL )
{
*prev_cluster_ptr = *cluster_ptr;
}
}
*index_ptr = index;
*cluster_ptr = cluster;
return(error_code);
}