RossMeikleham / FUSE-VMU

FUSE implementation of the Dreamcast VMU filesystem

FUSE VMU

A FUSE (Filesystem in userspace) implementation of the Sega Dreamcast's VMU (Visual Memory Unit) for Linux and OSX.

Design Decisions

The VMU filesystem is similar to the FAT filesystem except that it is entirely flat (no directories). Also in a FAT filesystem the size of a file in bytes is stored in the directory entry for the given file; which unfortunately isn't true for the VMU filesystem. The VMU assumes all files are "VMS" files which have a "header block" which contains the full filesize. I decided on making this implementation somewhat practical which means files aren't assumed to be VMS files and as result there is only information on the block size of a file. So the reported filesize of a given file is a multiple of a blocksize on disk (multiples of 512 bytes). I may decide to change this at some point.

Required

• Linux : FUSE Kernel Module enabled
• OSX : OSXFuse

Docker Builds

• docker build -t fuse-vmu .
• Produces a docker image in which the fuse_vmu binary is in the /usr/bin folder

Native Builds

Required

• Linux : libfuse userspace library
• gcc or clang version which supports C99
• cmake
• (If running unit tests a version of gcc or clang which supports C++11)
• (If running unit tests the google test framework)

Building

git clone http://github.com/RossMeikleham/Fuse-VMU
cd Fuse-VMU
mkdir build
cd build
cmake ..
make

The "fuse-vmu" binary should be in the Fuse-VMU/build/bin folder

Running

./fuse-vmu <vmu_file_path> [fuse_args] <mount_path>

Building + Mounting the example VMU filesystem

git clone http://github.com/RossMeikleham/Fuse-VMU
cd Fuse-VMU
mkdir build
cd build
cmake ..
make
mkdir MOUNT_POINT
./bin/fuse_vmu ../example/example_vmu.bin -f MOUNT_POINT

Unmounting

umount <mount_path>

Building + Running Unit Tests

git clone http://github.com/RossMeikleham/Fuse-VMU
cd Fuse-VMU/test
mkdir build
cd build
cmake ..
make
bin/fuse_vmu_tests