[Toybox] macOS realpath test failures

[Rob Landley]

On 1/10/23 15:46, Rob Landley wrote:
> I note I'm building mkroot images for the release so this bugfix won't be in
> 0.8.9, but Android has its own sync points. :)
> 
> On 1/9/23 18:10, enh wrote:
>> and here's the ls -lR for it...
> 
> This has been on my todo list because I need to make an f2fs filesystem, which
> is flash based, so I need to fake up a flash device with an erase block size. (I
> did that years ago and need to find my notes. Possibly easiest to do with qemu
> instead of that weird annotate-a-block-device driver?)

Huh, apparently not: I gave mkfs.f2fs a 128 meg zeroed image file and it assumed
512 sector size and ran with it.

$ hd f2fs.img | less
...
00000880  6a 70 67 00 00 00 00 00  67 69 66 00 00 00 00 00  |jpg.....gif.....|
00000890  70 6e 67 00 00 00 00 00  61 76 69 00 00 00 00 00  |png.....avi.....|
000008a0  64 69 76 78 00 00 00 00  6d 70 34 00 00 00 00 00  |divx....mp4.....|
000008b0  6d 70 33 00 00 00 00 00  33 67 70 00 00 00 00 00  |mp3.....3gp.....|
000008c0  77 6d 76 00 00 00 00 00  77 6d 61 00 00 00 00 00  |wmv.....wma.....|
000008d0  6d 70 65 67 00 00 00 00  6d 6b 76 00 00 00 00 00  |mpeg....mkv.....|
000008e0  6d 6f 76 00 00 00 00 00  61 73 78 00 00 00 00 00  |mov.....asx.....|
000008f0  61 73 66 00 00 00 00 00  77 6d 78 00 00 00 00 00  |asf.....wmx.....|
00000900  73 76 69 00 00 00 00 00  77 76 78 00 00 00 00 00  |svi.....wvx.....|
00000910  77 6d 00 00 00 00 00 00  6d 70 67 00 00 00 00 00  |wm......mpg.....|
00000920  6d 70 65 00 00 00 00 00  72 6d 00 00 00 00 00 00  |mpe.....rm......|
00000930  6f 67 67 00 00 00 00 00  6a 70 65 67 00 00 00 00  |ogg.....jpeg....|
00000940  76 69 64 65 6f 00 00 00  61 70 6b 00 00 00 00 00  |video...apk.....|
00000950  73 6f 00 00 00 00 00 00  64 62 00 00 00 00 00 00  |so......db......|

I do not understand what this thing is up to at all, but I suppose I don't
really NEED to at the moment? (This is an empty filesystem, I was wondering what
the formatter put into it and "a whole bunch of filetype extensions" was not on
my bingo card.)

>> FAIL: realpath -s .. eats symlink in $PWD
>> echo -ne '' | cd dos && realpath -s ..
> 
> The -s says "don't expand symlinks" so logically it means ".." should strip the
> last entry off of $PWD instead of traversing the filesystem? (That's why it
> expects that output, anyway...)
> 
>> --- expected 2023-01-09 21:52:49.611701819 +0000
>> +++ actual 2023-01-09 21:52:49.635701818 +0000
>> @@ -1 +1 @@
>> -/data/local/tmp/toybox-tests-tmp.a8tofxJqRN/realpath
>> +/data/local/tmp/toybox-tests-tmp.a8tofxJqRN/realpath/one
> 
> The ls contents look right. I'll see if I can set up a test environment later
> today...

Let's see...

$ sudo mount -o loop f2fs.img sub
$ cp -a generated/testdir/testdir/. sub/. # post-realpath test debris
$ cd sub/dos
$ toybox realpath -s ..
/home/landley/toybox/toybox/sub

Nope, it's not reproducing for me under debian's f2fs loopback mount either.
Built with android-ndk-r25b just to be sure.

Oddly enough:

$ realpath -s ..
/home/landley/toybox/toybox/sub/one

This is a behavior difference between toybox and gnu. (Hence the "toyonly" on
the test.) I have NO idea how your test plumbing would wind up running the gnu
version while triggering "toyonly" to run it, though...

> Rob

Still Rob