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On Thu, Aug 21, 2008 at 10:47 AM, Donnie Berkholz <dberkholz@g.o> wrote: |
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> I just encountered a problem recently and wondered whether your work |
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> might help it at all. The situation is uninstalling a library that |
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> system packages link against. The problem I hit involves |
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> sys-apps/shadow[USE=audit] and sys-process/audit, which I just hit on my |
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> own system, breaking /bin/login. |
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> |
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> It seems like this could become part of the linkage map and thus give |
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> the user a warning, if it's not already -- I haven't been following this |
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> incredibly closely. |
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> |
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> What do you think? |
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|
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In situations where a package is updated resulting in a new ABI for a |
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library (eg suppose libaudit.so.0 were updated to libaudit.so.1 in a |
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newer version of sys-process/audit), preserved libs would keep the old |
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libraries around by adding them to the CONTENTS of the newer package |
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so that libaudit.so.0 is still available for binaries that link to it. |
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This is done by finding consumers (linked binaries) of files |
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(libraries) that are being unmerged via calling |
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LinkageMap.findConsumers on files to be unmerged. However, in the |
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situation you provided, the package is removed, so (and I'm assuming |
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here) the only problem is deciding what to do with those needed |
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libraries. Since sys-process/audit is being removed, there is no good |
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candidate package that would own the files necessary to preserve the |
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libraries, but throwing a warning to the user is certainly feasible |
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using a similar method to find preserved libraries. |
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|
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As for using MissingLibraryConsumerSet in this situation, it'd |
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probably be too slow to calculate the set after each unmerge since the |
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set checks dependencies of the entire system. To give you an idea, on |
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my older laptop it takes about 20-30 seconds to calculate the set (and |
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more like 10s on subsequent runs due to vfs caching inodes and such). |
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So it'd be much quicker to simply find consumers of files to be |
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unmerged and give a warning if any are found as this won't involve |
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nearly as much filesystem access. |
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Now in the situation where needed libraries have already been |
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uninstalled and binaries are broken, MissingLibraryConsumerSet can be |
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used to emerge packages necessary to fix the state of the system... if |
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you can login, that is :) |
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|
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Lucian |
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