Mounting tar archives as a filesystem in WebAssembly
4 hours ago
- #virtual filesystem
- #WebAssembly
- #tar archives
- Mounting tar archives as a filesystem in WebAssembly allows direct access to files without extracting them.
- A metadata index file lists size and offsets of files within the tar, enabling zero-copy access.
- Emscripten's WORKERFS backend slices the tar blob on demand, serving reads without copying data.
- The tar-vfs-index npm package generates JSON metadata compatible with file_packager format.
- Tar archives have a flat layout with contiguous file data, making them suitable as a VFS backend store.
- For gzipped tar files, browser native decompression is used before mounting.
- Metadata can be served separately or appended to the tar archive for self-contained files.
- This approach reduces memory usage and speeds up loading, beneficial in constrained environments like WebR.