In article <Xns93ED4437D57E6Rob.Greene@216.168.3.44>,
 Rob Greene <greeneratcharterdotnet> wrote:

> "John B. Matthews" <nospam@nospam.com> wrote in news:nospam-
> 35F98B.00402505092003@clmboh1-nws3.columbus.rr.com:
> 
> > Note that ProDOS delete() has significant problems. More as this 
> > develops.
> 
> That sounds familiar.  It is on the TODO list - although the description I 
> left myself isn't the best: delete does not seem to delete in all 
> circumstances.
> 
> Hmmm... let me know!  I'll be out this weekend, but I may be able to join 
> in the hunt later if the need arises.
> -Rob

Rob: Here's the delete() fixes:

8. In ProdosFormatDisk.createFile(), add 
fileEntry.setKeyPointer(0); if this is a recyled directory 
entry, a subsequent call to setFileData will try to free blocks 
that previously belonged to the deleted file. These blocks may 
have subsequently been allocated to another file.

    fileEntry.setKeyPointer(0); //may have been recycled

Also, call setSeedlingFile(), rather than setSaplingFile().

9. A file entry needs a header pointer: In ProdosFileEntry add

    /**
     * Set the block number of the  block for the directory
     * that describes this file.
     */
    public void setHeaderPointer(int headerPointer) {
        byte[] entry = readFileEntry();
        AppleUtil.setWordValue(entry, 0x25, headerPointer);
        writeFileEntry(entry);
    }

10. Initailize header pointer in ProdosFormatDisk.createFile(), 
add

    int headerBlock = blockNumber;
    ...
    fileEntry.setHeaderPointer(headerBlock);

11. In ProdosFileEntry.delete(), the file count in the entry's 
directory header should be decremented.  [ProDOS Tech. Ref. 
B.2.2 B.2.3]  Also, both the storage type and the name length 
should be set to zero. [ProDOS Tech. Ref. B.2.4]

    /**
     * Delete the file.
     */
    public void delete() {
        getDisk().freeBlocks(this);

        //decrement file count in header block
        int headerBlock = getHeaderPointer();
        byte[] data = getDisk().readBlock(headerBlock);
        int fileCount = AppleUtil.getWordValue(data, 0x25);
        if (fileCount != 0) fileCount--;
        AppleUtil.setWordValue(data, 0x25, fileCount);
        getDisk().writeBlock(headerBlock, data);

        //clear storage type and name length
        data = readFileEntry();
        data[0] = 0;
        writeFileEntry(data);
    }

12. And a new TextFileFilter:

    /**
     * Process the given FileEntry and return a byte array 
     * with filtered data; use PrintWriter to get platform 
     * agnostic line endings.
     */
    public byte[] filter(FileEntry fileEntry) {
        byte[] fileData = fileEntry.getFileData();
        int offset = 0;
        ByteArrayOutputStream byteArray = new
            ByteArrayOutputStream(fileData.length);
        PrintWriter printWriter = new
            PrintWriter(byteArray, true);
        while (offset < fileData.length) {
            char c = (char)(fileData[offset] & 0x7f);
            if (c != 0) {
                if (c == 0x0d) { //Apple line end
                    printWriter.println();
                } else {
                    printWriter.print(c);
                }
            }
            offset++;
        }
        return byteArray.toByteArray();
    }

John
----
jmatthews at wright dot edu
www dot wright dot edu/~john.matthews/