Ejemplo n.º 1
0
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, &current_cluster, &current_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);
}  
Ejemplo n.º 2
0
_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);
}