Re: [PATCH] Fix handle leak in builtin-pack-objects

From: Alex Riesen <raa.lkml@gmail.com>
Date: Nov 19, 2008, 14:17 UTC
Message-ID: <81b0412b0811190617t4a9df151m886700672a21fad8@mail.gmail.com>
In-Reply-To: <49241AEF.1080808@viscovery.net>

2008/11/19 Johannes Sixt <j.sixt@viscovery.net>:

Show 25 quoted lines

> Alex Riesen schrieb:
>> 2008/11/19 Nicolas Pitre <nico@cam.org>:
>>> On Wed, 19 Nov 2008, Johannes Sixt wrote:
>>>> The work-around is to write the repacked objects to a file of a different
>>>> name, and replace the original after git-pack-objects has terminated.
>>>>
>>>> Signed-off-by: Johannes Sixt <j6t@kdbg.org>
>>> Acked-by: Nicolas Pitre <nico@cam.org>
>>
>> Are you sure? Will it work in a real repository? Were noone does
>> rename the previous pack files into packtmp-something?
>
> Oh, the patch only works around the failure in the test case. In a real
> repository there is usually no problem because the destination pack file
> does not exist.
>
> The unusual case is where you do this:
>
>  $ git rev-list -10 HEAD | git pack-objects foobar
>
> twice in a row: In this case the second invocation fails on Windows
> because the destination pack file already exists *and* is open. But not
> even git-repack does this even if it is called twice. OTOH, the test case
> *does* exactly this.
>

Still bad...

BTW, the patch _does_ fix the "unusual case" for me. IOW, I plainly copied your rev-list|pack-objects into command line. As expected, it fails for Junio's master (after the second run) and works with the patch:

  $ git rev-list -10 HEAD | ./git pack-objects .git/objects/pack/foobar
  Counting objects: 10, done.
  Compressing objects: 100% (9/9), done.
  82864ec14cd06e6089543a1419762e4cd40f7988
  Writing objects: 100% (10/10), done.
  Total 10 (delta 1), reused 10 (delta 1)

  $ git rev-list -10 HEAD | ./git pack-objects .git/objects/pack/foobar
  Counting objects: 10, done.
  Compressing objects: 100% (9/9), done.
  fatal: unable to rename temporary pack file: Permission denied

  $ git cherry-pick fix-fd-leak
  Finished one cherry-pick.
  [master]: created e629465: "Fix handle leak in builtin-pack-objects"
   1 files changed, 1 insertions(+), 0 deletions(-)

  $ git rev-list -10 HEAD | ./git pack-objects .git/objects/pack/foobar
  Counting objects: 10, done.
  Compressing objects: 100% (9/9), done.
  0e43d919a2a8336fd740d8d9b8f9f78d49e855e5
  Writing objects: 100% (10/10), done.
  Total 10 (delta 1), reused 9 (delta 1)

  $ git rev-list -10 HEAD | ./git pack-objects .git/objects/pack/foobar
  Counting objects: 10, done.
  Compressing objects: 100% (9/9), done.
  0e43d919a2a8336fd740d8d9b8f9f78d49e855e5
  Writing objects: 100% (10/10), done.
  Total 10 (delta 1), reused 10 (delta 1)

  $ git rev-list -10 HEAD | ./git pack-objects .git/objects/pack/foobar
  Counting objects: 10, done.
  Compressing objects: 100% (9/9), done.
  0e43d919a2a8336fd740d8d9b8f9f78d49e855e5
  Writing objects: 100% (10/10), done.
  Total 10 (delta 1), reused 10 (delta 1)