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authorVincent Ambo <Vincent Ambo>2020-01-11T23·36+0000
committerVincent Ambo <Vincent Ambo>2020-01-11T23·36+0000
commit1b593e1ea4d2af0f6444d9a7788d5d99abd6fde5 (patch)
treee3accb9beed5c4c1b5a05c99db71ab2841f0ed04 /perl/Git/SVN/Ra.pm
Squashed 'third_party/git/' content from commit cb71568594
git-subtree-dir: third_party/git
git-subtree-split: cb715685942260375e1eb8153b0768a376e4ece7
Diffstat (limited to 'perl/Git/SVN/Ra.pm')
-rw-r--r--perl/Git/SVN/Ra.pm708
1 files changed, 708 insertions, 0 deletions
diff --git a/perl/Git/SVN/Ra.pm b/perl/Git/SVN/Ra.pm
new file mode 100644
index 000000000000..56ad9870bcfd
--- /dev/null
+++ b/perl/Git/SVN/Ra.pm
@@ -0,0 +1,708 @@
+package Git::SVN::Ra;
+use vars qw/@ISA $config_dir $_ignore_refs_regex $_log_window_size/;
+use strict;
+use warnings;
+use Memoize;
+use Git::SVN::Utils qw(
+	canonicalize_url
+	canonicalize_path
+	add_path_to_url
+);
+
+use SVN::Ra;
+BEGIN {
+	@ISA = qw(SVN::Ra);
+}
+
+my ($ra_invalid, $can_do_switch, %ignored_err, $RA);
+
+BEGIN {
+	# enforce temporary pool usage for some simple functions
+	no strict 'refs';
+	for my $f (qw/rev_proplist get_latest_revnum get_uuid get_repos_root
+	              get_file/) {
+		my $SUPER = "SUPER::$f";
+		*$f = sub {
+			my $self = shift;
+			my $pool = SVN::Pool->new;
+			my @ret = $self->$SUPER(@_,$pool);
+			$pool->clear;
+			wantarray ? @ret : $ret[0];
+		};
+	}
+}
+
+# serf has a bug that leads to a coredump upon termination if the
+# remote access object is left around (not fixed yet in serf 1.3.1).
+# Explicitly free it to work around the issue.
+END {
+	$RA = undef;
+	$ra_invalid = 1;
+}
+
+sub _auth_providers () {
+	require SVN::Client;
+	my @rv = (
+	  SVN::Client::get_simple_provider(),
+	  SVN::Client::get_ssl_server_trust_file_provider(),
+	  SVN::Client::get_simple_prompt_provider(
+	    \&Git::SVN::Prompt::simple, 2),
+	  SVN::Client::get_ssl_client_cert_file_provider(),
+	  SVN::Client::get_ssl_client_cert_prompt_provider(
+	    \&Git::SVN::Prompt::ssl_client_cert, 2),
+	  SVN::Client::get_ssl_client_cert_pw_file_provider(),
+	  SVN::Client::get_ssl_client_cert_pw_prompt_provider(
+	    \&Git::SVN::Prompt::ssl_client_cert_pw, 2),
+	  SVN::Client::get_username_provider(),
+	  SVN::Client::get_ssl_server_trust_prompt_provider(
+	    \&Git::SVN::Prompt::ssl_server_trust),
+	  SVN::Client::get_username_prompt_provider(
+	    \&Git::SVN::Prompt::username, 2)
+	);
+
+	# earlier 1.6.x versions would segfault, and <= 1.5.x didn't have
+	# this function
+	if (::compare_svn_version('1.6.15') >= 0) {
+		my $config = SVN::Core::config_get_config($config_dir);
+		my ($p, @a);
+		# config_get_config returns all config files from
+		# ~/.subversion, auth_get_platform_specific_client_providers
+		# just wants the config "file".
+		@a = ($config->{'config'}, undef);
+		$p = SVN::Core::auth_get_platform_specific_client_providers(@a);
+		# Insert the return value from
+		# auth_get_platform_specific_providers
+		unshift @rv, @$p;
+	}
+	\@rv;
+}
+
+sub prepare_config_once {
+	SVN::_Core::svn_config_ensure($config_dir, undef);
+	my ($baton, $callbacks) = SVN::Core::auth_open_helper(_auth_providers);
+	my $config = SVN::Core::config_get_config($config_dir);
+	my $conf_t = $config->{'config'};
+
+	no warnings 'once';
+	# The usage of $SVN::_Core::SVN_CONFIG_* variables
+	# produces warnings that variables are used only once.
+	# I had not found the better way to shut them up, so
+	# the warnings of type 'once' are disabled in this block.
+	if (SVN::_Core::svn_config_get_bool($conf_t,
+	    $SVN::_Core::SVN_CONFIG_SECTION_AUTH,
+	    $SVN::_Core::SVN_CONFIG_OPTION_STORE_PASSWORDS,
+	    1) == 0) {
+		my $val = '1';
+		if (::compare_svn_version('1.9.0') < 0) { # pre-SVN r1553823
+			my $dont_store_passwords = 1;
+			$val = bless \$dont_store_passwords, "_p_void";
+		}
+		SVN::_Core::svn_auth_set_parameter($baton,
+		    $SVN::_Core::SVN_AUTH_PARAM_DONT_STORE_PASSWORDS,
+		    $val);
+	}
+	if (SVN::_Core::svn_config_get_bool($conf_t,
+	    $SVN::_Core::SVN_CONFIG_SECTION_AUTH,
+	    $SVN::_Core::SVN_CONFIG_OPTION_STORE_AUTH_CREDS,
+	    1) == 0) {
+		$Git::SVN::Prompt::_no_auth_cache = 1;
+	}
+
+	return ($config, $baton, $callbacks);
+} # no warnings 'once'
+
+INIT {
+	Memoize::memoize '_auth_providers';
+	Memoize::memoize 'prepare_config_once';
+}
+
+sub new {
+	my ($class, $url) = @_;
+	$url = canonicalize_url($url);
+	return $RA if ($RA && $RA->url eq $url);
+
+	::_req_svn();
+
+	$RA = undef;
+	my ($config, $baton, $callbacks) = prepare_config_once();
+	my $self = SVN::Ra->new(url => $url, auth => $baton,
+	                      config => $config,
+			      pool => SVN::Pool->new,
+	                      auth_provider_callbacks => $callbacks);
+	$RA = bless $self, $class;
+
+	# Make sure its canonicalized
+	$self->url($url);
+	$self->{svn_path} = $url;
+	$self->{repos_root} = $self->get_repos_root;
+	$self->{svn_path} =~ s#^\Q$self->{repos_root}\E(/|$)##;
+	$self->{cache} = { check_path => { r => 0, data => {} },
+	                   get_dir => { r => 0, data => {} } };
+
+	return $RA;
+}
+
+sub url {
+	my $self = shift;
+
+	if (@_) {
+		my $url = shift;
+		$self->{url} = canonicalize_url($url);
+		return;
+	}
+
+	return $self->{url};
+}
+
+sub check_path {
+	my ($self, $path, $r) = @_;
+	my $cache = $self->{cache}->{check_path};
+	if ($r == $cache->{r} && exists $cache->{data}->{$path}) {
+		return $cache->{data}->{$path};
+	}
+	my $pool = SVN::Pool->new;
+	my $t = $self->SUPER::check_path($path, $r, $pool);
+	$pool->clear;
+	if ($r != $cache->{r}) {
+		%{$cache->{data}} = ();
+		$cache->{r} = $r;
+	}
+	$cache->{data}->{$path} = $t;
+}
+
+sub get_dir {
+	my ($self, $dir, $r) = @_;
+	my $cache = $self->{cache}->{get_dir};
+	if ($r == $cache->{r}) {
+		if (my $x = $cache->{data}->{$dir}) {
+			return wantarray ? @$x : $x->[0];
+		}
+	}
+	my $pool = SVN::Pool->new;
+	my ($d, undef, $props);
+
+	if (::compare_svn_version('1.4.0') >= 0) {
+		# n.b. in addition to being potentially more efficient,
+		# this works around what appears to be a bug in some
+		# SVN 1.8 versions
+		my $kind = 1; # SVN_DIRENT_KIND
+		($d, undef, $props) = $self->get_dir2($dir, $r, $kind, $pool);
+	} else {
+		($d, undef, $props) = $self->SUPER::get_dir($dir, $r, $pool);
+	}
+	my %dirents = map { $_ => { kind => $d->{$_}->kind } } keys %$d;
+	$pool->clear;
+	if ($r != $cache->{r}) {
+		%{$cache->{data}} = ();
+		$cache->{r} = $r;
+	}
+	$cache->{data}->{$dir} = [ \%dirents, $r, $props ];
+	wantarray ? (\%dirents, $r, $props) : \%dirents;
+}
+
+# get_log(paths, start, end, limit,
+#         discover_changed_paths, strict_node_history, receiver)
+sub get_log {
+	my ($self, @args) = @_;
+	my $pool = SVN::Pool->new;
+
+	# svn_log_changed_path_t objects passed to get_log are likely to be
+	# overwritten even if only the refs are copied to an external variable,
+	# so we should dup the structures in their entirety.  Using an
+	# externally passed pool (instead of our temporary and quickly cleared
+	# pool in Git::SVN::Ra) does not help matters at all...
+	my $receiver = pop @args;
+	my $prefix = "/".$self->{svn_path};
+	$prefix =~ s#/+($)##;
+	my $prefix_regex = qr#^\Q$prefix\E#;
+	push(@args, sub {
+		my ($paths) = $_[0];
+		return &$receiver(@_) unless $paths;
+		$_[0] = ();
+		foreach my $p (keys %$paths) {
+			my $i = $paths->{$p};
+			# Make path relative to our url, not repos_root
+			$p =~ s/$prefix_regex//;
+			my %s = map { $_ => $i->$_; }
+				qw/copyfrom_path copyfrom_rev action/;
+			if ($s{'copyfrom_path'}) {
+				$s{'copyfrom_path'} =~ s/$prefix_regex//;
+				$s{'copyfrom_path'} = canonicalize_path($s{'copyfrom_path'});
+			}
+			$_[0]{$p} = \%s;
+		}
+		&$receiver(@_);
+	});
+
+
+	# the limit parameter was not supported in SVN 1.1.x, so we
+	# drop it.  Therefore, the receiver callback passed to it
+	# is made aware of this limitation by being wrapped if
+	# the limit passed to is being wrapped.
+	if (::compare_svn_version('1.2.0') <= 0) {
+		my $limit = splice(@args, 3, 1);
+		if ($limit > 0) {
+			my $receiver = pop @args;
+			push(@args, sub { &$receiver(@_) if (--$limit >= 0) });
+		}
+	}
+	my $ret = $self->SUPER::get_log(@args, $pool);
+	$pool->clear;
+	$ret;
+}
+
+# uncommon, only for ancient SVN (<= 1.4.2)
+sub trees_match {
+	require IO::File;
+	require SVN::Client;
+	my ($self, $url1, $rev1, $url2, $rev2) = @_;
+	my $ctx = SVN::Client->new(auth => _auth_providers);
+	my $out = IO::File->new_tmpfile;
+
+	# older SVN (1.1.x) doesn't take $pool as the last parameter for
+	# $ctx->diff(), so we'll create a default one
+	my $pool = SVN::Pool->new_default_sub;
+
+	$ra_invalid = 1; # this will open a new SVN::Ra connection to $url1
+	$ctx->diff([], $url1, $rev1, $url2, $rev2, 1, 1, 0, $out, $out);
+	$out->flush;
+	my $ret = (($out->stat)[7] == 0);
+	close $out or croak $!;
+
+	$ret;
+}
+
+sub get_commit_editor {
+	my ($self, $log, $cb, $pool) = @_;
+
+	my @lock = (::compare_svn_version('1.2.0') >= 0) ? (undef, 0) : ();
+	$self->SUPER::get_commit_editor($log, $cb, @lock, $pool);
+}
+
+sub gs_do_update {
+	my ($self, $rev_a, $rev_b, $gs, $editor) = @_;
+	my $new = ($rev_a == $rev_b);
+	my $path = $gs->path;
+
+	if ($new && -e $gs->{index}) {
+		unlink $gs->{index} or die
+		  "Couldn't unlink index: $gs->{index}: $!\n";
+	}
+	my $pool = SVN::Pool->new;
+	$editor->set_path_strip($path);
+	my (@pc) = split m#/#, $path;
+	my $reporter = $self->do_update($rev_b, (@pc ? shift @pc : ''),
+	                                1, $editor, $pool);
+	my @lock = (::compare_svn_version('1.2.0') >= 0) ? (undef) : ();
+
+	# Since we can't rely on svn_ra_reparent being available, we'll
+	# just have to do some magic with set_path to make it so
+	# we only want a partial path.
+	my $sp = '';
+	my $final = join('/', @pc);
+	while (@pc) {
+		$reporter->set_path($sp, $rev_b, 0, @lock, $pool);
+		$sp .= '/' if length $sp;
+		$sp .= shift @pc;
+	}
+	die "BUG: '$sp' != '$final'\n" if ($sp ne $final);
+
+	$reporter->set_path($sp, $rev_a, $new, @lock, $pool);
+
+	$reporter->finish_report($pool);
+	$pool->clear;
+	$editor->{git_commit_ok};
+}
+
+# this requires SVN 1.4.3 or later (do_switch didn't work before 1.4.3, and
+# svn_ra_reparent didn't work before 1.4)
+sub gs_do_switch {
+	my ($self, $rev_a, $rev_b, $gs, $url_b, $editor) = @_;
+	my $path = $gs->path;
+	my $pool = SVN::Pool->new;
+
+	my $old_url = $self->url;
+	my $full_url = add_path_to_url( $self->url, $path );
+	my ($ra, $reparented);
+
+	if ($old_url =~ m#^svn(\+\w+)?://# ||
+	    ($full_url =~ m#^https?://# &&
+	     canonicalize_url($full_url) ne $full_url)) {
+		$_[0] = undef;
+		$self = undef;
+		$RA = undef;
+		$ra = Git::SVN::Ra->new($full_url);
+		$ra_invalid = 1;
+	} elsif ($old_url ne $full_url) {
+		SVN::_Ra::svn_ra_reparent(
+			$self->{session},
+			canonicalize_url($full_url),
+			$pool
+		);
+		$self->url($full_url);
+		$reparented = 1;
+	}
+
+	$ra ||= $self;
+	$url_b = canonicalize_url($url_b);
+	my $reporter = $ra->do_switch($rev_b, '', 1, $url_b, $editor, $pool);
+	my @lock = (::compare_svn_version('1.2.0') >= 0) ? (undef) : ();
+	$reporter->set_path('', $rev_a, 0, @lock, $pool);
+	$reporter->finish_report($pool);
+
+	if ($reparented) {
+		SVN::_Ra::svn_ra_reparent($self->{session}, $old_url, $pool);
+		$self->url($old_url);
+	}
+
+	$pool->clear;
+	$editor->{git_commit_ok};
+}
+
+sub longest_common_path {
+	my ($gsv, $globs) = @_;
+	my %common;
+	my $common_max = scalar @$gsv;
+
+	foreach my $gs (@$gsv) {
+		my @tmp = split m#/#, $gs->path;
+		my $p = '';
+		foreach (@tmp) {
+			$p .= length($p) ? "/$_" : $_;
+			$common{$p} ||= 0;
+			$common{$p}++;
+		}
+	}
+	$globs ||= [];
+	$common_max += scalar @$globs;
+	foreach my $glob (@$globs) {
+		my @tmp = split m#/#, $glob->{path}->{left};
+		my $p = '';
+		foreach (@tmp) {
+			$p .= length($p) ? "/$_" : $_;
+			$common{$p} ||= 0;
+			$common{$p}++;
+		}
+	}
+
+	my $longest_path = '';
+	foreach (sort {length $b <=> length $a} keys %common) {
+		if ($common{$_} == $common_max) {
+			$longest_path = $_;
+			last;
+		}
+	}
+	$longest_path;
+}
+
+sub gs_fetch_loop_common {
+	my ($self, $base, $head, $gsv, $globs) = @_;
+	return if ($base > $head);
+	# Make sure the cat_blob open2 FileHandle is created before calling
+	# SVN::Pool::new_default so that it does not incorrectly end up in the pool.
+	$::_repository->_open_cat_blob_if_needed;
+	my $gpool = SVN::Pool->new_default;
+	my $ra_url = $self->url;
+	my $reload_ra = sub {
+		$_[0] = undef;
+		$self = undef;
+		$RA = undef;
+		$gpool->clear;
+		$self = Git::SVN::Ra->new($ra_url);
+		$ra_invalid = undef;
+	};
+	my $inc = $_log_window_size;
+	my ($min, $max) = ($base, $head < $base + $inc ? $head : $base + $inc);
+	my $longest_path = longest_common_path($gsv, $globs);
+	my $find_trailing_edge;
+	while (1) {
+		my %revs;
+		my $err;
+		my $err_handler = $SVN::Error::handler;
+		$SVN::Error::handler = sub {
+			($err) = @_;
+			skip_unknown_revs($err);
+		};
+		sub _cb {
+			my ($paths, $r, $author, $date, $log) = @_;
+			[ $paths,
+			  { author => $author, date => $date, log => $log } ];
+		}
+		$self->get_log([$longest_path], $min, $max, 0, 1, 1,
+		               sub { $revs{$_[1]} = _cb(@_) });
+		if ($err) {
+			print "Checked through r$max\r";
+		} else {
+			$find_trailing_edge = 1;
+		}
+		if ($err and $find_trailing_edge) {
+			print STDERR "Path '$longest_path' ",
+				     "was probably deleted:\n",
+				     $err->expanded_message,
+				     "\nWill attempt to follow ",
+				     "revisions r$min .. r$max ",
+				     "committed before the deletion\n";
+			my $hi = $max;
+			while (--$hi >= $min) {
+				my $ok;
+				$self->get_log([$longest_path], $min, $hi,
+				               0, 1, 1, sub {
+				               $ok = $_[1];
+				               $revs{$_[1]} = _cb(@_) });
+				if ($ok) {
+					print STDERR "r$min .. r$ok OK\n";
+					last;
+				}
+			}
+			$find_trailing_edge = 0;
+		}
+		$SVN::Error::handler = $err_handler;
+
+		my %exists = map { $_->path => $_ } @$gsv;
+		foreach my $r (sort {$a <=> $b} keys %revs) {
+			my ($paths, $logged) = @{delete $revs{$r}};
+
+			foreach my $gs ($self->match_globs(\%exists, $paths,
+			                                   $globs, $r)) {
+				if ($gs->rev_map_max >= $r) {
+					next;
+				}
+				next unless $gs->match_paths($paths, $r);
+				$gs->{logged_rev_props} = $logged;
+				if (my $last_commit = $gs->last_commit) {
+					$gs->assert_index_clean($last_commit);
+				}
+				my $log_entry = $gs->do_fetch($paths, $r);
+				if ($log_entry) {
+					$gs->do_git_commit($log_entry);
+				}
+				$Git::SVN::INDEX_FILES{$gs->{index}} = 1;
+			}
+			foreach my $g (@$globs) {
+				my $k = "svn-remote.$g->{remote}." .
+				        "$g->{t}-maxRev";
+				Git::SVN::tmp_config($k, $r);
+			}
+			$reload_ra->() if $ra_invalid;
+		}
+		# pre-fill the .rev_db since it'll eventually get filled in
+		# with '0' x40 if something new gets committed
+		foreach my $gs (@$gsv) {
+			next if $gs->rev_map_max >= $max;
+			next if defined $gs->rev_map_get($max);
+			$gs->rev_map_set($max, 0 x40);
+		}
+		foreach my $g (@$globs) {
+			my $k = "svn-remote.$g->{remote}.$g->{t}-maxRev";
+			Git::SVN::tmp_config($k, $max);
+		}
+		last if $max >= $head;
+		$min = $max + 1;
+		$max += $inc;
+		$max = $head if ($max > $head);
+
+		$reload_ra->();
+	}
+	Git::SVN::gc();
+}
+
+sub get_dir_globbed {
+	my ($self, $left, $depth, $r) = @_;
+
+	my @x = eval { $self->get_dir($left, $r) };
+	return unless scalar @x == 3;
+	my $dirents = $x[0];
+	my @finalents;
+	foreach my $de (keys %$dirents) {
+		next if $dirents->{$de}->{kind} != $SVN::Node::dir;
+		if ($depth > 1) {
+			my @args = ("$left/$de", $depth - 1, $r);
+			foreach my $dir ($self->get_dir_globbed(@args)) {
+				push @finalents, "$de/$dir";
+			}
+		} else {
+			push @finalents, $de;
+		}
+	}
+	@finalents;
+}
+
+# return value: 0 -- don't ignore, 1 -- ignore
+sub is_ref_ignored {
+	my ($g, $p) = @_;
+	my $refname = $g->{ref}->full_path($p);
+	return 1 if defined($g->{ignore_refs_regex}) &&
+	            $refname =~ m!$g->{ignore_refs_regex}!;
+	return 0 unless defined($_ignore_refs_regex);
+	return 1 if $refname =~ m!$_ignore_refs_regex!o;
+	return 0;
+}
+
+sub match_globs {
+	my ($self, $exists, $paths, $globs, $r) = @_;
+
+	sub get_dir_check {
+		my ($self, $exists, $g, $r) = @_;
+
+		my @dirs = $self->get_dir_globbed($g->{path}->{left},
+		                                  $g->{path}->{depth},
+		                                  $r);
+
+		foreach my $de (@dirs) {
+			my $p = $g->{path}->full_path($de);
+			next if $exists->{$p};
+			next if (length $g->{path}->{right} &&
+				 ($self->check_path($p, $r) !=
+				  $SVN::Node::dir));
+			next unless $p =~ /$g->{path}->{regex}/;
+			$exists->{$p} = Git::SVN->init($self->url, $p, undef,
+					 $g->{ref}->full_path($de), 1);
+		}
+	}
+	foreach my $g (@$globs) {
+		if (my $path = $paths->{"/$g->{path}->{left}"}) {
+			if ($path->{action} =~ /^[AR]$/) {
+				get_dir_check($self, $exists, $g, $r);
+			}
+		}
+		foreach (keys %$paths) {
+			if (/$g->{path}->{left_regex}/ &&
+			    !/$g->{path}->{regex}/) {
+				next if $paths->{$_}->{action} !~ /^[AR]$/;
+				get_dir_check($self, $exists, $g, $r);
+			}
+			next unless /$g->{path}->{regex}/;
+			my $p = $1;
+			my $pathname = $g->{path}->full_path($p);
+			next if is_ref_ignored($g, $p);
+			next if $exists->{$pathname};
+			next if ($self->check_path($pathname, $r) !=
+			         $SVN::Node::dir);
+			$exists->{$pathname} = Git::SVN->init(
+			                      $self->url, $pathname, undef,
+			                      $g->{ref}->full_path($p), 1);
+		}
+		my $c = '';
+		foreach (split m#/#, $g->{path}->{left}) {
+			$c .= "/$_";
+			next unless ($paths->{$c} &&
+			             ($paths->{$c}->{action} =~ /^[AR]$/));
+			get_dir_check($self, $exists, $g, $r);
+		}
+	}
+	values %$exists;
+}
+
+sub minimize_url {
+	my ($self) = @_;
+	return $self->url if ($self->url eq $self->{repos_root});
+	my $url = $self->{repos_root};
+	my @components = split(m!/!, $self->{svn_path});
+	my $c = '';
+	do {
+		$url = add_path_to_url($url, $c);
+		eval {
+			my $ra = (ref $self)->new($url);
+			my $latest = $ra->get_latest_revnum;
+			$ra->get_log("", $latest, 0, 1, 0, 1, sub {});
+		};
+	} while ($@ && defined($c = shift @components));
+
+	return canonicalize_url($url);
+}
+
+sub can_do_switch {
+	my $self = shift;
+	unless (defined $can_do_switch) {
+		my $pool = SVN::Pool->new;
+		my $rep = eval {
+			$self->do_switch(1, '', 0, $self->url,
+			                 SVN::Delta::Editor->new, $pool);
+		};
+		if ($@) {
+			$can_do_switch = 0;
+		} else {
+			$rep->abort_report($pool);
+			$can_do_switch = 1;
+		}
+		$pool->clear;
+	}
+	$can_do_switch;
+}
+
+sub skip_unknown_revs {
+	my ($err) = @_;
+	my $errno = $err->apr_err();
+	# Maybe the branch we're tracking didn't
+	# exist when the repo started, so it's
+	# not an error if it doesn't, just continue
+	#
+	# Wonderfully consistent library, eh?
+	# 160013 - svn:// and file://
+	# 175002 - http(s)://
+	# 175007 - http(s):// (this repo required authorization, too...)
+	#   More codes may be discovered later...
+	if ($errno == 175007 || $errno == 175002 || $errno == 160013) {
+		my $err_key = $err->expanded_message;
+		# revision numbers change every time, filter them out
+		$err_key =~ s/\d+/\0/g;
+		$err_key = "$errno\0$err_key";
+		unless ($ignored_err{$err_key}) {
+			warn "W: Ignoring error from SVN, path probably ",
+			     "does not exist: ($errno): ",
+			     $err->expanded_message,"\n";
+			warn "W: Do not be alarmed at the above message ",
+			     "git-svn is just searching aggressively for ",
+			     "old history.\n",
+			     "This may take a while on large repositories\n";
+			$ignored_err{$err_key} = 1;
+		}
+		return;
+	}
+	die "Error from SVN, ($errno): ", $err->expanded_message,"\n";
+}
+
+1;
+__END__
+
+=head1 NAME
+
+Git::SVN::Ra - Subversion remote access functions for git-svn
+
+=head1 SYNOPSIS
+
+    use Git::SVN::Ra;
+
+    my $ra = Git::SVN::Ra->new($branchurl);
+    my ($dirents, $fetched_revnum, $props) =
+        $ra->get_dir('.', $SVN::Core::INVALID_REVNUM);
+
+=head1 DESCRIPTION
+
+This is a wrapper around the L<SVN::Ra> module for use by B<git-svn>.
+It fills in some default parameters (such as the authentication
+scheme), smooths over incompatibilities between libsvn versions, adds
+caching, and implements some functions specific to B<git-svn>.
+
+Do not use it unless you are developing git-svn.  The interface will
+change as git-svn evolves.
+
+=head1 DEPENDENCIES
+
+Subversion perl bindings,
+L<Git::SVN>.
+
+C<Git::SVN::Ra> has not been tested using callers other than
+B<git-svn> itself.
+
+=head1 SEE ALSO
+
+L<SVN::Ra>.
+
+=head1 INCOMPATIBILITIES
+
+None reported.
+
+=head1 BUGS
+
+None.