unyaffs2

[Guest isambard]

Hi

I try to use the standard unyaffs2 tool to extract the image files from the ZTE, but this doesn't seem to work. Is anyone able to help with this? I feel like I'm constantly re-inventing the wheel with these small android problems. Thanks.

[Guest isambard]

Hmm. It seems that the images are not full yaffs2 images but are instead missing the 'spare' chunks. Urgh. More tool-smithing required.

[Guest rjm2k]

Hi

I try to use the standard unyaffs2 tool to extract the image files from the ZTE, but this doesn't seem to work. Is anyone able to help with this? I feel like I'm constantly re-inventing the wheel with these small android problems. Thanks.

I just use unyaffs

[Guest isambard]

I just use unyaffs

hmm. i tried 2 versions of it, one doesn't work, the other segfaults. :/

[Guest Arr Too]

There's a thread about this somewhere. If the system.img was created by a dumb copy [with, say, 'dd' -- which you can use for the boot and recovery partitions...] then it'll be broken. Nothing you can do with that really, unless you're really good at jigsaw puzzles. You need something like nanddump to do it properly, or something that creates an archive of the individual files (which is how ClockworkMod does it, I believe) -- a 'tar' will retain the permissions or else a zip will need a fixup script (like the update.zip format).

Edited January 1, 2011 by Arr Too

[Guest El Nino9]

I just use unyaffs

do you unyaffs the system.img the people dump on here or nandroid back ups or w.e?

@ isambard

i take it you're using windows?what file are you trying to unyaffs?is it the one from the hungerian rom the official system.img?

try loop mount it in linux would give better results. plus you can try different formats if unyaffs doesn't work

[Guest isambard]

do you unyaffs the system.img the people dump on here or nandroid back ups or w.e?

@ isambard

i take it you're using windows?what file are you trying to unyaffs?is it the one from the hungerian rom the official system.img?

try loop mount it in linux would give better results. plus you can try different formats if unyaffs doesn't work

i looked at the hungarian rom and also a romdump from sebastians tool. when i examined the romdump tool, it seemed to call DD internally so dumping without 'spare' bytes. though i couldn't see why the spare bytes should be necessary to extract the files - after all, if it is dumpable back on the system in a readable state from a DD, then it should also be readable on the computer.

i use linux, and loop mounting would be an option except that my kernel doesn't have yaffs2 compiled in and i'm loathe to compile a kernel only for this.

EDIT: fwiw, using the tools i compiled to create a yaffs2 image and then unyaffs'ing it works.

Edited January 1, 2011 by isambard

[Guest Arr Too]

when i examined the romdump tool, it seemed to call DD internally so dumping without 'spare' bytes.

I thought romdump did a tar? That's definitely the easiest and safest way to do it, with standard Unix tools.

though i couldn't see why the spare bytes should be necessary to extract the files

It contains the main filesystem data (rather than file data). Without the SPARE bytes you'll have a broken image, or a very interesting jigsaw puzzle (probably with lots of seemingly duplicate or discarded pieces).