Allow casper to use a squashfs filesystem within an arbitrary path

[Agostino Russo]

Bug 207137, Wubi's ISO image creation from a CD process failing, seems to be biting a fair number of users. A way around having to use the cd2iso tool and thus avoid the bug would be to copy only the squashfs. This change to casper implements the necessary code on the Ubuntu side for that.

check_dev in scripts/casper could be made more flexible if it was possible to look for a casper fs (is_casper_path) within an arbitrary path. At the moment check_dev supports scanning either devices or ISOs. This could be implemented with the following snippet:

if [ -d "${devname}" ]; then
  mount -o bind $devname $mountpoint
  if is_casper_path $mountpoint; then
    echo $mountpoint
    return 0
  endif
fi

TEST CASE:
"On my test system I couldn't get Wubi to install using the cd-rw drive in the machine. Since then I've added a dvd-rw and wubi installs flawlessly.

The cd installs to the part at the end of creating the image file at which point it throws up the error "Could not access cd, please make sure other applications are not using it and try again.""

As reported by davmor2 of the QA team.

A debdiff of the uploaded patch can be found here:
http://launchpadlibrarian.net/14822820/casper_1.132ubuntu0.1.debdiff

[Launchpad Janitor (janitor)]

This bug was fixed in the package casper - 1.132

---------------
casper (1.132) intrepid; urgency=low

  [ Colin Watson ]
  * Switch default unionfs implementation to aufs.

  [ Agostino Russo ]
  * Do not scan only vfat volumes when looking for cow devices (LP: #230703)
  * Allow casper to use a squashfs filesystem within an arbitrary path (LP:
    #230716, #207137)

 -- Evan Dandrea <email address hidden> Wed, 28 May 2008 15:01:30 -0400

[Martin Pitt (pitti)]

Accepted into -proposed, please test and give feedback here

[Agostino Russo (ago)]

Martin, that what tested in bug #207137 and it seems to have fixed the original problem, but you should also be aware that the patch introduced a regression in ubiquity/python-apt, see #243105

[Agostino Russo (ago)]

So basically the current status is that it is now possible to extract files from the CD without getting stacked (bug #207317 which was tested), but the installation will fail at the end (bug #243105). The new issue does not depend on casper per se', but on how bind-mounts are treated by apt (hence the new bug report).

[Agostino Russo (ago)]

bug #207137 is in fact tested in bug #204128
basically bug #204128 tests also bug #207137 #230716 and #238701

[Agostino Russo (ago)]

I have tested booting off a directory containing the extracted ISO content using the daily iso 20080620.1 and casper can boot properly (except for #243105)
I have tested booting off an ISO and installing and that also works well.

[Martin Pitt (pitti)]

Tested in bug 204128.

[Martin Pitt (pitti)]

Copied to hardy-updates.

[Martin Pitt (pitti)]

Sorry, not copied yet, I just saw that bug 230703 is still an issue. This needs to be reverted in hardy-proposed, not just in intrepid.

[Agostino Russo (ago)]

Martin,

Evan should have released casper 1.132ubuntu0.2, that reverts the 230703 patch.

[Steve Langasek (vorlon)]

casper 1.132ubuntu0.2 copied to hardy-updates.