Does undmg handle symlinks

[bwolf]

I tried it with a dmg containing relative symlinks like https://github.com/qutebrowser/qutebrowser/releases/download/v1.6.1/qutebrowser-1.6.1.dmg and all symlinks aren't present. Instead it seems the links are followed and copied, which does not work in the case of directory links. Is this correct and is there a easy way to fix it?

[matthewbauer]

Yeah, it doesn't look like that's supported. I think it should be pretty easy to fix. The code that handles this logic is right here:

undmg/hfslib.c

Lines 724 to 735 in 2b62ecf

	if (type == 0) {
	void *buffer = malloc(size);
	tarFile->seek(tarFile, curRecord + 512);
	tarFile->read(tarFile, buffer, size);
	AbstractFile *inFile = createAbstractFileFromMemory(&buffer, size);
	add_hfs(volume, inFile, fileName);
	free(buffer);
	} else if (type == 5) {
	newFolder(fileName, volume);
	} else if (type == 2) {
	makeSymlink(fileName, target, volume);
	}

I'm not sure what "type" value is coming up here

[bwolf]

I'm currently looking at extractAllInFolder (hfslib.c), adding debug information. The function hfs_untar is unused.

[lilyball]

I just ran into this issue. I tried to use this to unpack a .app and none of the symlinks were preserved.

[sikmir]

@matthewbauer Could you please make a release (1.0.4) to get this fix available in nixpkgs? I ran into this issue with many *.dmg.

[matthewbauer]

done in NixOS/nixpkgs#94106