[PATCH v2 0/2] allow git-svn fetching to work using serf

[PATCH v2 0/2] allow git-svn fetching to work using serf

[Kyle J. McKay]

From: "Kyle J. McKay" <mackyle@gmail.com>

This patch allows git-svn to fetch successfully using the
serf library when given an https?: url to fetch from.

Unfortunately some svn servers do not seem to be configured
well for use with the serf library.  This can cause fetching
to take longer compared to the neon library or actually
cause timeouts during the fetch.  When timeouts occur
git-svn can be safely restarted to fetch more revisions.

A new temp_is_locked function has been added to Git.pm
to facilitate using the minimal number of temp files
possible when using serf.

The problem that occurs when running git-svn fetch using
the serf library is that the previously used temp file
is not always unlocked before the next temp file needs
to be used.

To work around this problem, a new temp name is used
if the temp name that would otherwise be chosen is
currently locked.

Kyle J. McKay (2):
  Git.pm: add new temp_is_locked function
  git-svn: allow git-svn fetching to work using serf

 perl/Git.pm             | 39 +++++++++++++++++++++++++++++++++------
 perl/Git/SVN/Fetcher.pm |  6 ++++--
 2 files changed, 37 insertions(+), 8 deletions(-)

-- 
1.8.3

[PATCH v2 1/2] Git.pm: add new temp_is_locked function

[Kyle J. McKay]

From: "Kyle J. McKay" <mackyle@gmail.com>

The temp_is_locked function can be used to determine whether
or not a given name previously passed to temp_acquire is
currently locked.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
---
 perl/Git.pm | 39 +++++++++++++++++++++++++++++++++------
 1 file changed, 33 insertions(+), 6 deletions(-)

diff --git a/perl/Git.pm b/perl/Git.pm
index 7a252ef..74d9a73 100644
--- a/perl/Git.pm
+++ b/perl/Git.pm
@@ -61,7 +61,7 @@ require Exporter;
                 remote_refs prompt
                 get_tz_offset
                 credential credential_read credential_write
-                temp_acquire temp_release temp_reset temp_path);
+                temp_acquire temp_is_locked temp_release temp_reset temp_path);
 
 
 =head1 DESCRIPTION
@@ -1206,6 +1206,35 @@ sub temp_acquire {
 	$temp_fd;
 }
 
+=item temp_is_locked ( NAME )
+
+Returns true if the internal lock created by a previous C<temp_acquire()>
+call with C<NAME> is still in effect.
+
+When temp_acquire is called on a C<NAME>, it internally locks the temporary
+file mapped to C<NAME>.  That lock will not be released until C<temp_release()>
+is called with either the original C<NAME> or the L<File::Handle> that was
+returned from the original call to temp_acquire.
+
+Subsequent attempts to call C<temp_acquire()> with the same C<NAME> will fail
+unless there has been an intervening C<temp_release()> call for that C<NAME>
+(or its corresponding L<File::Handle> that was returned by the original
+C<temp_acquire()> call).
+
+If true is returned by C<temp_is_locked()> for a C<NAME>, an attempt to
+C<temp_acquire()> the same C<NAME> will cause an error unless
+C<temp_release> is first called on that C<NAME> (or its corresponding
+L<File::Handle> that was returned by the original C<temp_acquire()> call).
+
+=cut
+
+sub temp_is_locked {
+	my ($self, $name) = _maybe_self(@_);
+	my $temp_fd = \$TEMP_FILEMAP{$name};
+
+	defined $$temp_fd && $$temp_fd->opened && $TEMP_FILES{$$temp_fd}{locked};
+}
+
 =item temp_release ( NAME )
 
 =item temp_release ( FILEHANDLE )
@@ -1247,11 +1276,9 @@ sub _temp_cache {
 	_verify_require();
 
 	my $temp_fd = \$TEMP_FILEMAP{$name};
-	if (defined $$temp_fd and $$temp_fd->opened) {
-		if ($TEMP_FILES{$$temp_fd}{locked}) {
-			throw Error::Simple("Temp file with moniker '" .
-				$name . "' already in use");
-		}
+	if (temp_is_locked($name)) {
+		throw Error::Simple("Temp file with moniker '" .
+			$name . "' already in use");
 	} else {
 		if (defined $$temp_fd) {
 			# then we're here because of a closed handle.
-- 
1.8.3

[PATCH v2 2/2] git-svn: allow git-svn fetching to work using serf

[Kyle J. McKay]

From: "Kyle J. McKay" <mackyle@gmail.com>

When attempting to git-svn fetch files from an svn https?: url using
the serf library (the only choice starting with svn 1.8) the following
errors can occur:

Temp file with moniker 'svn_delta' already in use at Git.pm line 1250
Temp file with moniker 'git_blob' already in use at Git.pm line 1250

David Rothenberger <daveroth@acm.org> has determined the cause to
be that ra_serf does not drive the delta editor in a depth-first
manner [...]. Instead, the calls come in this order:

1. open_root
2. open_directory
3. add_file
4. apply_textdelta
5. add_file
6. apply_textdelta

When using the ra_serf access method, git-svn can end up needing
to create several temp files before the first one is closed.

This change causes a new temp file moniker to be generated if the
one that would otherwise have been used is currently locked.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
---
 perl/Git/SVN/Fetcher.pm | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/perl/Git/SVN/Fetcher.pm b/perl/Git/SVN/Fetcher.pm
index bd17418..10edb27 100644
--- a/perl/Git/SVN/Fetcher.pm
+++ b/perl/Git/SVN/Fetcher.pm
@@ -315,11 +315,13 @@ sub change_file_prop {
 sub apply_textdelta {
 	my ($self, $fb, $exp) = @_;
 	return undef if $self->is_path_ignored($fb->{path});
-	my $fh = $::_repository->temp_acquire('svn_delta');
+	my $suffix = 0;
+	++$suffix while $::_repository->temp_is_locked("svn_delta_${$}_$suffix");
+	my $fh = $::_repository->temp_acquire("svn_delta_${$}_$suffix");
 	# $fh gets auto-closed() by SVN::TxDelta::apply(),
 	# (but $base does not,) so dup() it for reading in close_file
 	open my $dup, '<&', $fh or croak $!;
-	my $base = $::_repository->temp_acquire('git_blob');
+	my $base = $::_repository->temp_acquire("git_blob_${$}_$suffix");
 
 	if ($fb->{blob}) {
 		my ($base_is_link, $size);
-- 
1.8.3