git-svn: better attempt to handle broken symlink updates

This is a followup to 7fc35e0e94,
(workaround a for broken symlinks in SVN).

Since broken SVN clients can commit svn:special files without
the magic "link " prefix, this can affect delta application
when we update the broken svn:special file.  So now we fall
back and retry the delta application on symlinks if having
a "link " prefix fails.

Our behavior differs from svn(1) (v1.5.1) slightly:

  When a svn:special file is created w/o a "link " prefix, svn
  will create a regular file (mode 100644 to git) with the
  contents of the blob as-is.

  Our behavior is to continue creating the symlink (mode 120000
  to git) with the contents of the blob as-is.  While this
  differs from current svn(1) behavior, this is easier and more
  efficient to implement (and the correctness of the svn(1) is
  debatable, since it's a workaround for a bug in the first
  place).

More information on this SVN bug is described here:
  http://subversion.tigris.org/issues/show_bug.cgi?id=2692

Signed-off-by: Eric Wong <normalperson@yhbt.net>
This commit is contained in:
Eric Wong 2009-01-11 16:51:11 -08:00
parent dbc6c74d08
commit baf5fa8a7f
2 changed files with 122 additions and 4 deletions

View File

@ -3380,19 +3380,35 @@ sub apply_textdelta {
open my $dup, '<&', $fh or croak $!;
my $base = $::_repository->temp_acquire('git_blob');
if ($fb->{blob}) {
my ($base_is_link, $size);
if ($fb->{mode_a} eq '120000' &&
! $self->{empty_symlinks}->{$fb->{path}}) {
print $base 'link ' or die "print $!\n";
$base_is_link = 1;
}
my $size = $::_repository->cat_blob($fb->{blob}, $base);
retry:
$size = $::_repository->cat_blob($fb->{blob}, $base);
die "Failed to read object $fb->{blob}" if ($size < 0);
if (defined $exp) {
seek $base, 0, 0 or croak $!;
my $got = ::md5sum($base);
die "Checksum mismatch: $fb->{path} $fb->{blob}\n",
"expected: $exp\n",
" got: $got\n" if ($got ne $exp);
if ($got ne $exp) {
my $err = "Checksum mismatch: ".
"$fb->{path} $fb->{blob}\n" .
"expected: $exp\n" .
" got: $got\n";
if ($base_is_link) {
warn $err,
"Retrying... (possibly ",
"a bad symlink from SVN)\n";
$::_repository->temp_reset($base);
$base_is_link = 0;
goto retry;
}
die $err;
}
}
}
seek $base, 0, 0 or croak $!;

102
t/t9132-git-svn-broken-symlink.sh Executable file
View File

@ -0,0 +1,102 @@
#!/bin/sh
test_description='test that git handles an svn repository with empty symlinks'
. ./lib-git-svn.sh
test_expect_success 'load svn dumpfile' '
svnadmin load "$rawsvnrepo" <<EOF
SVN-fs-dump-format-version: 2
UUID: 60780f9a-7df5-43b4-83ab-60e2c0673ef7
Revision-number: 0
Prop-content-length: 56
Content-length: 56
K 8
svn:date
V 27
2008-11-26T07:17:27.590577Z
PROPS-END
Revision-number: 1
Prop-content-length: 111
Content-length: 111
K 7
svn:log
V 4
test
K 10
svn:author
V 12
normalperson
K 8
svn:date
V 27
2008-11-26T07:18:03.511836Z
PROPS-END
Node-path: bar
Node-kind: file
Node-action: add
Prop-content-length: 33
Text-content-length: 4
Text-content-md5: 912ec803b2ce49e4a541068d495ab570
Content-length: 37
K 11
svn:special
V 1
*
PROPS-END
asdf
Revision-number: 2
Prop-content-length: 121
Content-length: 121
K 7
svn:log
V 13
bar => doink
K 10
svn:author
V 12
normalperson
K 8
svn:date
V 27
2008-11-27T03:55:31.601672Z
PROPS-END
Node-path: bar
Node-kind: file
Node-action: change
Text-content-length: 10
Text-content-md5: 92ca4fe7a9721f877f765c252dcd66c9
Content-length: 10
link doink
EOF
'
test_expect_success 'clone using git svn' 'git svn clone -r1 "$svnrepo" x'
test_expect_success '"bar" is a symlink that points to "asdf"' '
test -L x/bar &&
(cd x && test xasdf = x"`git cat-file blob HEAD:bar`")
'
test_expect_success 'get "bar" => symlink fix from svn' '
(cd x && git svn rebase)
'
test_expect_success '"bar" remains a proper symlink' '
test -L x/bar &&
(cd x && test xdoink = x"`git cat-file blob HEAD:bar`")
'
test_done