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-rw-r--r--perl/Git/SVN/Ra.pm698
1 files changed, 698 insertions, 0 deletions
diff --git a/perl/Git/SVN/Ra.pm b/perl/Git/SVN/Ra.pm
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+++ b/perl/Git/SVN/Ra.pm
@@ -0,0 +1,698 @@
+package Git::SVN::Ra;
+use vars qw/@ISA $config_dir $_ignore_refs_regex $_log_window_size/;
+use strict;
+use warnings;
+use Memoize;
+use SVN::Client;
+use Git::SVN::Utils qw(
+ canonicalize_url
+ canonicalize_path
+ add_path_to_url
+);
+
+use SVN::Ra;
+BEGIN {
+ @ISA = qw(SVN::Ra);
+}
+
+my ($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 () {
+ 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 $dont_store_passwords = 1;
+ 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,
+ $SVN::_Core::SVN_CONFIG_OPTION_STORE_PASSWORDS,
+ 1) == 0) {
+ SVN::_Core::svn_auth_set_parameter($baton,
+ $SVN::_Core::SVN_AUTH_PARAM_DONT_STORE_PASSWORDS,
+ bless (\$dont_store_passwords, "_p_void"));
+ }
+ if (SVN::_Core::svn_config_get_bool($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;
+ $ret;
+}
+
+sub trees_match {
+ my ($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);
+ 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("", $latest, 0, 1, 0, 1, sub {});
+ };
+ } while ($@ && ($c = shift @components));
+
+ return canonicalize_url($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.