waldheinz/fat32-lib

A Java library for manipulating FAT file systems.

fat32-lib's Issues

size calculation for cluster-offset might be short by one byte

(from Google Code)

Reported by marc.greim, Aug 11, 2013

on line 211 in ClusterChain.java (5e34cb7eb178) the partial read calculates the size to read as:

200 int size = Math.min(len,
211 (int) (clusterSize - (offset % clusterSize) - 1));

The subtraction of 1 at the end of the line seems wrong to me. In my tests removing the -1 solves issues while playing mp3/video after a seek.

Image File Does Not Work When Deploying to Pi Zero

I used the ImageBuilder class to build a simple 4 file Raspberry Pi boot image (containing a custom serial boot loader...not a linux OS). I use dd to transfer the image to an SD card. When I mount the card on my Mac, I see the files, and when I md5 all the files on the card, they match with the source directory. However, when I try to boot the Pi, it will not boot. However, if I re-mount the card on my Mac, and then copy the original files over the files deployed with the image (via the Finder), the Pi will then boot.

I would have thought that not having a partition table (via the super floppy format) might be a problem with the Pi, but simply copying files should not alter the partition table.

I see this really nice lib has not been updated in a while, but I would appreciate some guidance on what I might try to diagnose.

Navigation up the directory structure is impossible

Reported by ricardospadilha, Nov 8, 2010
Hi,

it seems that navigation up the directory structure is impossible, i.e., starting from a 2 or 3 levels deep directory it is impossible to navigate up to the grand-parent directory.

From any given FsDirectoryEntry we can access the parent FsDirectory through getParent(). However, from FsDirectory there is no way to access that directory's FsDirectoryEntry in order to find that directory's parent.

I think that in general both FsFile and FsDirectory should have methods to retrieve the underlying FsDirectory that supports them.

Bug in FatDirectoryEntry.parseLfn: Fat can get corrupted

Fat can get corrupted when you read an existing image and add an new entry to a directory with
a longname that will result in a shortname that is equal to an existing entry. For example if the root directory of an existing image contains a file named bundle.jar (with shortname bundle~1.jar) and you wil add another entry to the root directory say a directory named bundle.jar-embedded. This new entry also gets the shortname bundle~1.jar instead of bundle~2.jar. This happens because usedNames is missing bundle~1.jar as entry.

On Ubuntu IOException "missing boot sector signature" is thrown

The same code works under windows and mac.
The exception is thrown after calling
final FatFileSystem fileSystem = FatFileSystem.read(channel, true);
which at some point calls
public static BootSector read(BlockDevice device) throws IOException {

documentation

Hi,
I was trying for a while to find out how to use the library properly. Could you give a short information for e.g. loading an existing image, navigating throw some folders, create a file ?
I am having trouble to find the "user interface" classes.

Kind regards

Ensure that all deleted FS objects get invalidated

When a file / directory is deleted, it is still possible to manipulate the relevant object and most probably this will cause FS corruption.

Add JDK7 FileSystem Support

From Ernest at

http://waldheinz.de/2010/04/release-candidate-for-fat32-lib/

Have you put any thought to perhaps implementing a JDK7/NIO2 compliant FileSystemProvider (see http://download.oracle.com/javase/7/docs/technotes/guides/io/fsp/filesystemprovider.html) in order to make this available as a first-class supporter of the Path API introduced in NIO2?

There is a ZIP fs implementation included with JDK7, also some theoretical discussion about a ramdisk support of sorts, but no-one has done it, as far as I know. This seems to be the closest thing to it…

Change License to Apache v2 or BSD

I would like to use the fat32-lib in a commercial product. I do not need to modify the code. I would however like to distribute it as part of an überjar, which unfortunately makes it very difficult for the users to swap out the library for newer versions themselves (an LGPL requirement).

Would it be acceptable to you to relicense the code under a more permissive license (Apache 2 or BSD)?

Any changes I would have to make to the library would of course be contributed back.

Thanks,
Axel

Directories

If you use fsroot.addDirectory returns a DirectoryEntry when it should return another FsDirectory. Because if you only get a FsDirectoryEntry, you can not use Long file names that are already implemented to navigate throgh the directory tree. The only workaround is to directly use the FATspecific classes which I think were meant to be used via the generic File System Interface.

Additionally the call to addDirectory should also create the . and .. Directory entries so that the image used by another driver can actually navigate into that directory. I get an error doing that.

    File file = new File("C:\\fat32test.img");
    FileDisk filedisk = new FileDisk(file, false);

    FileSystem fs = FileSystemFactory.create(filedisk, false);
    FsDirectory fsroot = fs.getRoot();
    fsroot.
    FsDirectoryEntry subdir = fsroot.addDirectory("adddir");

Check why the releases are not propagated to Maven Central

Reported by [email protected], Sep 3, 2013

The latest available version is 0.6 ->

http://search.maven.org/#search%7Cga%7C1%7Cfat32-lib

Usage on android

How I can use this library on Android? Has any examples?

Properly deal with the unknown timezone

All times/dates on FAT file systems are stored in "local time". But it is nowhere recorded which is that local time zone, so it should be possible to specify it.

Or just do what Linux does.

Writing to SD Card image

Hi,

This library is great, but I am having an issue with writing to an SD card image.

I create it with the android tool 'mksdcard', then load it as a Fat32 File System using this API.
I proceed to mount the image, and the output looks like:
However, after writing each file to the card, trying to navigate the output looks like:

Joe-Laptop:/mnt/sd # ls -l
ls: cannot access docs: Input/output error
ls: cannot access projects: Input/output error
ls: cannot access codes: Input/output error
total 0
d????????? ? ? ? ? ? docs
d????????? ? ? ? ? ? codes
d????????? ? ? ? ? ? projects

Is there any way to ensure that the directories and file write correctly?

Entry unique name not freed when entry is moved

Great library - thanks for creating and maintaining it. I used this a couple of months ago and ran into what I think is a bug. The test case is below but basically if you move a file then it's unique name is not freed from its original parent directory, so you can't add a new file of the same name or move the old file back.

I fixed this in FatLfnDirectory.java by moving the call to "freeUniqueName()" from the remove() method (line 380) to the bottom of the the unlinkEntry() (now line 412).

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.fail;

import java.io.IOException;

import org.junit.Before;
import org.junit.Test;

import de.waldheinz.fs.fat.FatFileSystem;
import de.waldheinz.fs.fat.FatLfnDirectory;
import de.waldheinz.fs.fat.FatLfnDirectoryEntry;
import de.waldheinz.fs.fat.SuperFloppyFormatter;
import de.waldheinz.fs.util.RamDisk;


public class MoveToReplaceTest {

    private static final String FILE_NAME = "file"; 
    private static final String DIRECTORY_NAME = "dir"; 

    private FatLfnDirectoryEntry file;
    private FatLfnDirectoryEntry dir;
    private FatLfnDirectory root;
    private FatFileSystem fs;


    @Before
    public void setUp() throws IOException {
        RamDisk dev = new RamDisk(1024 * 1024);
        fs = SuperFloppyFormatter.get(dev).format();

        root = fs.getRoot();
        file = root.addFile(FILE_NAME);
        dir = root.addDirectory(DIRECTORY_NAME);

    }

    @Test
    public void moveToAndReplaceTest() throws IOException {
        // Move file form root to dir
        file.moveTo(dir.getDirectory(), DIRECTORY_NAME);

        // Check that the file has been moved and isn't in the original dir
        assertEquals(file.getParent(), dir.getDirectory());
        assertNull( root.getEntry(FILE_NAME) );

        // Create a new file with a SAME filename in the original dir
        try {
            root.addFile(FILE_NAME);
        } catch (IOException e) {
            // Code will fail here
            //  java.io.IOException: an entry named file already exists
            //  at de.waldheinz.fs.fat.FatLfnDirectory.checkUniqueName(FatLfnDirectory.java:162)
            //  at de.waldheinz.fs.fat.FatLfnDirectory.addFile(FatLfnDirectory.java:135)
            e.printStackTrace();
            fail("IO Exception");
        }
    }

}

Investigate Volume Label Charset

With the current implementation, the volume label can only contain characters which are

• ASCII and
• pass through ShortName.checkValidChars(..).

A recent Windows XP and Windows 7 allow more then that, but which charset is used remains unclear for now. Linux / KDE does not properly deal with these volume labels currently.

Move version history to Maven site

There's a Maven plugin for this.

de.waldheinz.fs.fat.DosFsckTest fails on Windows

All tests are currently Linux-specific and fail with:

java.io.IOException: Cannot run program "/usr/sbin/dosfsck": CreateProcess error=2, The system cannot find the file specified

Allow specifing the exact number of sectors per fat

Reported by [email protected], Today (16 hours ago)

This is currently calculated automatically. It would be nice to have a method that allows to override the default with an explicit value.

Long file names

fsroot.addFile can not add a file with a long file name. I think it should be.

    File file = new File("C:\\fat32test.img");
    FileDisk filedisk = new FileDisk(file, false);
    FileSystem fs = FileSystemFactory.create(filedisk, false);
    FsDirectory fsroot = fs.getRoot();
    fsroot.addFile("LOOOOOOONGFileName.txt");

Support use cases which do not permit LFN entries

Was once requested via email.