Package: apt Version: 0.9.4 Severity: grave Control: affects -1 aptitude X-Debbugs-CC: m...@debian.org, debian-rele...@lists.debian.org
Hi, Michael Prokop noticed that in some cases an aptitude update would fail with a "E: Method gave invalid 200 URI Start message" when using http.debian.net. After a lot of confusion and attempts to debug the problem, in a chroot where the issue could be reproduced, I eventually noticed that the versions of apt and libapt-pkg4.12 didn't match: apt: 0.8.15.9 (old version) libapt-pkg4.12: 0.9.7.2 (wheezy) aptitude: 0.6.8-1 (wheezy) The problem: When aptitude uses libapt-pkg to download a file, it starts an instance of the http method that doesn't include the changes made in #668111. This means that it sends the 103 redirection message as usual, but it handles it internally. Given that aptitude uses libapt-pkg4.12, it handles the 103 message in the new fashion and starts a new http process to handle the redirection. Since the first http process is handling the request internally, it eventually sends a 200 "URI Start" message with the original URI (the one of http.debian.net). By then, libapt-pkg4.12 has already marked such URI as done, removed it from the http:http.debian.net queue, and more importantly: changed the URI of the Itm (pkgAcquire::Queue::QItem). So, when it receives the 200 message it can't even match the URI of the message to a QItem, therefore aborting with the "E: Method gave invalid 200 URI Start message" error. Why APT still works: The old apt version works just fine because it uses libapt-pkg4.10, which means it handles the redirection internally. According to dpkg -S the libapt-pkg4.10 used by apt is provided by the apt package itself. I.e. it is not a separate package. Note: if it is not obvious enough, this isn't restricted to http.debian.net. Any mirror that sends a redirection could trigger this bug. Now, the easiest way to prevent this kind of conflict would be by adding a Depends: apt >= 0.9.4 to libapt-pkg4.12. Not sure how much trouble it would cause to a squeeze->wheezy upgrade, as it would force apt to also be upgraded when upgrading aptitude (upgrading apt already requires upgrading aptitude.) It also introduces a soft dependency loop, but it seems harmless. The alternative way to express it would be by adding a Breaks: apt (<< 0.9.4) to libapt-pkg4.12. I think this last form would cause more noise during the upgrade. Introducing a new redirection code (104?) would probably cause more trouble at this point than handling the problem via the dependencies system. Toughts? Sorry for not noticing it before. Somehow I knew I should have bumped the redirection code :-/ Cheers, -- Raphael Geissert - Debian Developer www.debian.org - get.debian.net -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
