Extract Git::SVN from git-svn into its own .pm file.

Except for adding the 1; at the end, this is a straight copy & paste.

Tests still pass, but its doubtful Git::SVN will compile on its own
without git-svn being loaded.  Next commit will fix that.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Eric Wong <normalperson@yhbt.net>

2 files changed, 2320 insertions, 0 deletions

diff --git a/perl/Git/SVN.pm b/perl/Git/SVN.pm
new file mode 100644
index 0000000000..c71c041986
--- /dev/null
+++ b/perl/Git/SVN.pm
@@ -0,0 +1,2319 @@
+package Git::SVN;
+use strict;
+use warnings;
+use Fcntl qw/:DEFAULT :seek/;
+use constant rev_map_fmt => 'NH40';
+use vars qw/$default_repo_id $default_ref_id $_no_metadata $_follow_parent
+            $_repack $_repack_flags $_use_svm_props $_head
+            $_use_svnsync_props $no_reuse_existing $_minimize_url
+	    $_use_log_author $_add_author_from $_localtime/;
+use Carp qw/croak/;
+use File::Path qw/mkpath/;
+use File::Copy qw/copy/;
+use IPC::Open3;
+use Time::Local;
+use Memoize;  # core since 5.8.0, Jul 2002
+use Memoize::Storable;
+use POSIX qw(:signal_h);
+
+use Git qw(
+    command
+    command_oneline
+    command_noisy
+    command_output_pipe
+    command_close_pipe
+);
+use Git::SVN::Utils qw(fatal can_compress);
+
+my $can_use_yaml;
+BEGIN {
+	$can_use_yaml = eval { require Git::SVN::Memoize::YAML; 1};
+}
+
+my ($_gc_nr, $_gc_period);
+
+# properties that we do not log:
+my %SKIP_PROP;
+BEGIN {
+	%SKIP_PROP = map { $_ => 1 } qw/svn:wc:ra_dav:version-url
+	                                svn:special svn:executable
+	                                svn:entry:committed-rev
+	                                svn:entry:last-author
+	                                svn:entry:uuid
+	                                svn:entry:committed-date/;
+
+	# some options are read globally, but can be overridden locally
+	# per [svn-remote "..."] section.  Command-line options will *NOT*
+	# override options set in an [svn-remote "..."] section
+	no strict 'refs';
+	for my $option (qw/follow_parent no_metadata use_svm_props
+			   use_svnsync_props/) {
+		my $key = $option;
+		$key =~ tr/_//d;
+		my $prop = "-$option";
+		*$option = sub {
+			my ($self) = @_;
+			return $self->{$prop} if exists $self->{$prop};
+			my $k = "svn-remote.$self->{repo_id}.$key";
+			eval { command_oneline(qw/config --get/, $k) };
+			if ($@) {
+				$self->{$prop} = ${"Git::SVN::_$option"};
+			} else {
+				my $v = command_oneline(qw/config --bool/,$k);
+				$self->{$prop} = $v eq 'false' ? 0 : 1;
+			}
+			return $self->{$prop};
+		}
+	}
+}
+
+
+my (%LOCKFILES, %INDEX_FILES);
+END {
+	unlink keys %LOCKFILES if %LOCKFILES;
+	unlink keys %INDEX_FILES if %INDEX_FILES;
+}
+
+sub resolve_local_globs {
+	my ($url, $fetch, $glob_spec) = @_;
+	return unless defined $glob_spec;
+	my $ref = $glob_spec->{ref};
+	my $path = $glob_spec->{path};
+	foreach (command(qw#for-each-ref --format=%(refname) refs/#)) {
+		next unless m#^$ref->{regex}$#;
+		my $p = $1;
+		my $pathname = desanitize_refname($path->full_path($p));
+		my $refname = desanitize_refname($ref->full_path($p));
+		if (my $existing = $fetch->{$pathname}) {
+			if ($existing ne $refname) {
+				die "Refspec conflict:\n",
+				    "existing: $existing\n",
+				    " globbed: $refname\n";
+			}
+			my $u = (::cmt_metadata("$refname"))[0];
+			$u =~ s!^\Q$url\E(/|$)!! or die
+			  "$refname: '$url' not found in '$u'\n";
+			if ($pathname ne $u) {
+				warn "W: Refspec glob conflict ",
+				     "(ref: $refname):\n",
+				     "expected path: $pathname\n",
+				     "    real path: $u\n",
+				     "Continuing ahead with $u\n";
+				next;
+			}
+		} else {
+			$fetch->{$pathname} = $refname;
+		}
+	}
+}
+
+sub parse_revision_argument {
+	my ($base, $head) = @_;
+	if (!defined $::_revision || $::_revision eq 'BASE:HEAD') {
+		return ($base, $head);
+	}
+	return ($1, $2) if ($::_revision =~ /^(\d+):(\d+)$/);
+	return ($::_revision, $::_revision) if ($::_revision =~ /^\d+$/);
+	return ($head, $head) if ($::_revision eq 'HEAD');
+	return ($base, $1) if ($::_revision =~ /^BASE:(\d+)$/);
+	return ($1, $head) if ($::_revision =~ /^(\d+):HEAD$/);
+	die "revision argument: $::_revision not understood by git-svn\n";
+}
+
+sub fetch_all {
+	my ($repo_id, $remotes) = @_;
+	if (ref $repo_id) {
+		my $gs = $repo_id;
+		$repo_id = undef;
+		$repo_id = $gs->{repo_id};
+	}
+	$remotes ||= read_all_remotes();
+	my $remote = $remotes->{$repo_id} or
+	             die "[svn-remote \"$repo_id\"] unknown\n";
+	my $fetch = $remote->{fetch};
+	my $url = $remote->{url} or die "svn-remote.$repo_id.url not defined\n";
+	my (@gs, @globs);
+	my $ra = Git::SVN::Ra->new($url);
+	my $uuid = $ra->get_uuid;
+	my $head = $ra->get_latest_revnum;
+
+	# ignore errors, $head revision may not even exist anymore
+	eval { $ra->get_log("", $head, 0, 1, 0, 1, sub { $head = $_[1] }) };
+	warn "W: $@\n" if $@;
+
+	my $base = defined $fetch ? $head : 0;
+
+	# read the max revs for wildcard expansion (branches/*, tags/*)
+	foreach my $t (qw/branches tags/) {
+		defined $remote->{$t} or next;
+		push @globs, @{$remote->{$t}};
+
+		my $max_rev = eval { tmp_config(qw/--int --get/,
+		                         "svn-remote.$repo_id.${t}-maxRev") };
+		if (defined $max_rev && ($max_rev < $base)) {
+			$base = $max_rev;
+		} elsif (!defined $max_rev) {
+			$base = 0;
+		}
+	}
+
+	if ($fetch) {
+		foreach my $p (sort keys %$fetch) {
+			my $gs = Git::SVN->new($fetch->{$p}, $repo_id, $p);
+			my $lr = $gs->rev_map_max;
+			if (defined $lr) {
+				$base = $lr if ($lr < $base);
+			}
+			push @gs, $gs;
+		}
+	}
+
+	($base, $head) = parse_revision_argument($base, $head);
+	$ra->gs_fetch_loop_common($base, $head, \@gs, \@globs);
+}
+
+sub read_all_remotes {
+	my $r = {};
+	my $use_svm_props = eval { command_oneline(qw/config --bool
+	    svn.useSvmProps/) };
+	$use_svm_props = $use_svm_props eq 'true' if $use_svm_props;
+	my $svn_refspec = qr{\s*(.*?)\s*:\s*(.+?)\s*};
+	foreach (grep { s/^svn-remote\.// } command(qw/config -l/)) {
+		if (m!^(.+)\.fetch=$svn_refspec$!) {
+			my ($remote, $local_ref, $remote_ref) = ($1, $2, $3);
+			die("svn-remote.$remote: remote ref '$remote_ref' "
+			    . "must start with 'refs/'\n")
+				unless $remote_ref =~ m{^refs/};
+			$local_ref = uri_decode($local_ref);
+			$r->{$remote}->{fetch}->{$local_ref} = $remote_ref;
+			$r->{$remote}->{svm} = {} if $use_svm_props;
+		} elsif (m!^(.+)\.usesvmprops=\s*(.*)\s*$!) {
+			$r->{$1}->{svm} = {};
+		} elsif (m!^(.+)\.url=\s*(.*)\s*$!) {
+			$r->{$1}->{url} = $2;
+		} elsif (m!^(.+)\.pushurl=\s*(.*)\s*$!) {
+			$r->{$1}->{pushurl} = $2;
+		} elsif (m!^(.+)\.ignore-refs=\s*(.*)\s*$!) {
+			$r->{$1}->{ignore_refs_regex} = $2;
+		} elsif (m!^(.+)\.(branches|tags)=$svn_refspec$!) {
+			my ($remote, $t, $local_ref, $remote_ref) =
+			                                     ($1, $2, $3, $4);
+			die("svn-remote.$remote: remote ref '$remote_ref' ($t) "
+			    . "must start with 'refs/'\n")
+				unless $remote_ref =~ m{^refs/};
+			$local_ref = uri_decode($local_ref);
+			my $rs = {
+			    t => $t,
+			    remote => $remote,
+			    path => Git::SVN::GlobSpec->new($local_ref, 1),
+			    ref => Git::SVN::GlobSpec->new($remote_ref, 0) };
+			if (length($rs->{ref}->{right}) != 0) {
+				die "The '*' glob character must be the last ",
+				    "character of '$remote_ref'\n";
+			}
+			push @{ $r->{$remote}->{$t} }, $rs;
+		}
+	}
+
+	map {
+		if (defined $r->{$_}->{svm}) {
+			my $svm;
+			eval {
+				my $section = "svn-remote.$_";
+				$svm = {
+					source => tmp_config('--get',
+					    "$section.svm-source"),
+					replace => tmp_config('--get',
+					    "$section.svm-replace"),
+				}
+			};
+			$r->{$_}->{svm} = $svm;
+		}
+	} keys %$r;
+
+	foreach my $remote (keys %$r) {
+		foreach ( grep { defined $_ }
+			  map { $r->{$remote}->{$_} } qw(branches tags) ) {
+			foreach my $rs ( @$_ ) {
+				$rs->{ignore_refs_regex} =
+				    $r->{$remote}->{ignore_refs_regex};
+			}
+		}
+	}
+
+	$r;
+}
+
+sub init_vars {
+	$_gc_nr = $_gc_period = 1000;
+	if (defined $_repack || defined $_repack_flags) {
+	       warn "Repack options are obsolete; they have no effect.\n";
+	}
+}
+
+sub verify_remotes_sanity {
+	return unless -d $ENV{GIT_DIR};
+	my %seen;
+	foreach (command(qw/config -l/)) {
+		if (m!^svn-remote\.(?:.+)\.fetch=.*:refs/remotes/(\S+)\s*$!) {
+			if ($seen{$1}) {
+				die "Remote ref refs/remote/$1 is tracked by",
+				    "\n  \"$_\"\nand\n  \"$seen{$1}\"\n",
+				    "Please resolve this ambiguity in ",
+				    "your git configuration file before ",
+				    "continuing\n";
+			}
+			$seen{$1} = $_;
+		}
+	}
+}
+
+sub find_existing_remote {
+	my ($url, $remotes) = @_;
+	return undef if $no_reuse_existing;
+	my $existing;
+	foreach my $repo_id (keys %$remotes) {
+		my $u = $remotes->{$repo_id}->{url} or next;
+		next if $u ne $url;
+		$existing = $repo_id;
+		last;
+	}
+	$existing;
+}
+
+sub init_remote_config {
+	my ($self, $url, $no_write) = @_;
+	$url =~ s!/+$!!; # strip trailing slash
+	my $r = read_all_remotes();
+	my $existing = find_existing_remote($url, $r);
+	if ($existing) {
+		unless ($no_write) {
+			print STDERR "Using existing ",
+				     "[svn-remote \"$existing\"]\n";
+		}
+		$self->{repo_id} = $existing;
+	} elsif ($_minimize_url) {
+		my $min_url = Git::SVN::Ra->new($url)->minimize_url;
+		$existing = find_existing_remote($min_url, $r);
+		if ($existing) {
+			unless ($no_write) {
+				print STDERR "Using existing ",
+					     "[svn-remote \"$existing\"]\n";
+			}
+			$self->{repo_id} = $existing;
+		}
+		if ($min_url ne $url) {
+			unless ($no_write) {
+				print STDERR "Using higher level of URL: ",
+					     "$url => $min_url\n";
+			}
+			my $old_path = $self->{path};
+			$self->{path} = $url;
+			$self->{path} =~ s!^\Q$min_url\E(/|$)!!;
+			if (length $old_path) {
+				$self->{path} .= "/$old_path";
+			}
+			$url = $min_url;
+		}
+	}
+	my $orig_url;
+	if (!$existing) {
+		# verify that we aren't overwriting anything:
+		$orig_url = eval {
+			command_oneline('config', '--get',
+					"svn-remote.$self->{repo_id}.url")
+		};
+		if ($orig_url && ($orig_url ne $url)) {
+			die "svn-remote.$self->{repo_id}.url already set: ",
+			    "$orig_url\nwanted to set to: $url\n";
+		}
+	}
+	my ($xrepo_id, $xpath) = find_ref($self->refname);
+	if (!$no_write && defined $xpath) {
+		die "svn-remote.$xrepo_id.fetch already set to track ",
+		    "$xpath:", $self->refname, "\n";
+	}
+	unless ($no_write) {
+		command_noisy('config',
+			      "svn-remote.$self->{repo_id}.url", $url);
+		$self->{path} =~ s{^/}{};
+		$self->{path} =~ s{%([0-9A-F]{2})}{chr hex($1)}ieg;
+		command_noisy('config', '--add',
+			      "svn-remote.$self->{repo_id}.fetch",
+			      "$self->{path}:".$self->refname);
+	}
+	$self->{url} = $url;
+}
+
+sub find_by_url { # repos_root and, path are optional
+	my ($class, $full_url, $repos_root, $path) = @_;
+
+	return undef unless defined $full_url;
+	remove_username($full_url);
+	remove_username($repos_root) if defined $repos_root;
+	my $remotes = read_all_remotes();
+	if (defined $full_url && defined $repos_root && !defined $path) {
+		$path = $full_url;
+		$path =~ s#^\Q$repos_root\E(?:/|$)##;
+	}
+	foreach my $repo_id (keys %$remotes) {
+		my $u = $remotes->{$repo_id}->{url} or next;
+		remove_username($u);
+		next if defined $repos_root && $repos_root ne $u;
+
+		my $fetch = $remotes->{$repo_id}->{fetch} || {};
+		foreach my $t (qw/branches tags/) {
+			foreach my $globspec (@{$remotes->{$repo_id}->{$t}}) {
+				resolve_local_globs($u, $fetch, $globspec);
+			}
+		}
+		my $p = $path;
+		my $rwr = rewrite_root({repo_id => $repo_id});
+		my $svm = $remotes->{$repo_id}->{svm}
+			if defined $remotes->{$repo_id}->{svm};
+		unless (defined $p) {
+			$p = $full_url;
+			my $z = $u;
+			my $prefix = '';
+			if ($rwr) {
+				$z = $rwr;
+				remove_username($z);
+			} elsif (defined $svm) {
+				$z = $svm->{source};
+				$prefix = $svm->{replace};
+				$prefix =~ s#^\Q$u\E(?:/|$)##;
+				$prefix =~ s#/$##;
+			}
+			$p =~ s#^\Q$z\E(?:/|$)#$prefix# or next;
+		}
+		foreach my $f (keys %$fetch) {
+			next if $f ne $p;
+			return Git::SVN->new($fetch->{$f}, $repo_id, $f);
+		}
+	}
+	undef;
+}
+
+sub init {
+	my ($class, $url, $path, $repo_id, $ref_id, $no_write) = @_;
+	my $self = _new($class, $repo_id, $ref_id, $path);
+	if (defined $url) {
+		$self->init_remote_config($url, $no_write);
+	}
+	$self;
+}
+
+sub find_ref {
+	my ($ref_id) = @_;
+	foreach (command(qw/config -l/)) {
+		next unless m!^svn-remote\.(.+)\.fetch=
+		              \s*(.*?)\s*:\s*(.+?)\s*$!x;
+		my ($repo_id, $path, $ref) = ($1, $2, $3);
+		if ($ref eq $ref_id) {
+			$path = '' if ($path =~ m#^\./?#);
+			return ($repo_id, $path);
+		}
+	}
+	(undef, undef, undef);
+}
+
+sub new {
+	my ($class, $ref_id, $repo_id, $path) = @_;
+	if (defined $ref_id && !defined $repo_id && !defined $path) {
+		($repo_id, $path) = find_ref($ref_id);
+		if (!defined $repo_id) {
+			die "Could not find a \"svn-remote.*.fetch\" key ",
+			    "in the repository configuration matching: ",
+			    "$ref_id\n";
+		}
+	}
+	my $self = _new($class, $repo_id, $ref_id, $path);
+	if (!defined $self->{path} || !length $self->{path}) {
+		my $fetch = command_oneline('config', '--get',
+		                            "svn-remote.$repo_id.fetch",
+		                            ":$ref_id\$") or
+		     die "Failed to read \"svn-remote.$repo_id.fetch\" ",
+		         "\":$ref_id\$\" in config\n";
+		($self->{path}, undef) = split(/\s*:\s*/, $fetch);
+	}
+	$self->{path} =~ s{/+}{/}g;
+	$self->{path} =~ s{\A/}{};
+	$self->{path} =~ s{/\z}{};
+	$self->{url} = command_oneline('config', '--get',
+	                               "svn-remote.$repo_id.url") or
+                  die "Failed to read \"svn-remote.$repo_id.url\" in config\n";
+	$self->{pushurl} = eval { command_oneline('config', '--get',
+	                          "svn-remote.$repo_id.pushurl") };
+	$self->rebuild;
+	$self;
+}
+
+sub refname {
+	my ($refname) = $_[0]->{ref_id} ;
+
+	# It cannot end with a slash /, we'll throw up on this because
+	# SVN can't have directories with a slash in their name, either:
+	if ($refname =~ m{/$}) {
+		die "ref: '$refname' ends with a trailing slash, this is ",
+		    "not permitted by git nor Subversion\n";
+	}
+
+	# It cannot have ASCII control character space, tilde ~, caret ^,
+	# colon :, question-mark ?, asterisk *, space, or open bracket [
+	# anywhere.
+	#
+	# Additionally, % must be escaped because it is used for escaping
+	# and we want our escaped refname to be reversible
+	$refname =~ s{([ \%~\^:\?\*\[\t])}{uc sprintf('%%%02x',ord($1))}eg;
+
+	# no slash-separated component can begin with a dot .
+	# /.* becomes /%2E*
+	$refname =~ s{/\.}{/%2E}g;
+
+	# It cannot have two consecutive dots .. anywhere
+	# .. becomes %2E%2E
+	$refname =~ s{\.\.}{%2E%2E}g;
+
+	# trailing dots and .lock are not allowed
+	# .$ becomes %2E and .lock becomes %2Elock
+	$refname =~ s{\.(?=$|lock$)}{%2E};
+
+	# the sequence @{ is used to access the reflog
+	# @{ becomes %40{
+	$refname =~ s{\@\{}{%40\{}g;
+
+	return $refname;
+}
+
+sub desanitize_refname {
+	my ($refname) = @_;
+	$refname =~ s{%(?:([0-9A-F]{2}))}{chr hex($1)}eg;
+	return $refname;
+}
+
+sub svm_uuid {
+	my ($self) = @_;
+	return $self->{svm}->{uuid} if $self->svm;
+	$self->ra;
+	unless ($self->{svm}) {
+		die "SVM UUID not cached, and reading remotely failed\n";
+	}
+	$self->{svm}->{uuid};
+}
+
+sub svm {
+	my ($self) = @_;
+	return $self->{svm} if $self->{svm};
+	my $svm;
+	# see if we have it in our config, first:
+	eval {
+		my $section = "svn-remote.$self->{repo_id}";
+		$svm = {
+		  source => tmp_config('--get', "$section.svm-source"),
+		  uuid => tmp_config('--get', "$section.svm-uuid"),
+		  replace => tmp_config('--get', "$section.svm-replace"),
+		}
+	};
+	if ($svm && $svm->{source} && $svm->{uuid} && $svm->{replace}) {
+		$self->{svm} = $svm;
+	}
+	$self->{svm};
+}
+
+sub _set_svm_vars {
+	my ($self, $ra) = @_;
+	return $ra if $self->svm;
+
+	my @err = ( "useSvmProps set, but failed to read SVM properties\n",
+		    "(svm:source, svm:uuid) ",
+		    "from the following URLs:\n" );
+	sub read_svm_props {
+		my ($self, $ra, $path, $r) = @_;
+		my $props = ($ra->get_dir($path, $r))[2];
+		my $src = $props->{'svm:source'};
+		my $uuid = $props->{'svm:uuid'};
+		return undef if (!$src || !$uuid);
+
+		chomp($src, $uuid);
+
+		$uuid =~ m{^[0-9a-f\-]{30,}$}i
+		    or die "doesn't look right - svm:uuid is '$uuid'\n";
+
+		# the '!' is used to mark the repos_root!/relative/path
+		$src =~ s{/?!/?}{/};
+		$src =~ s{/+$}{}; # no trailing slashes please
+		# username is of no interest
+		$src =~ s{(^[a-z\+]*://)[^/@]*@}{$1};
+
+		my $replace = $ra->{url};
+		$replace .= "/$path" if length $path;
+
+		my $section = "svn-remote.$self->{repo_id}";
+		tmp_config("$section.svm-source", $src);
+		tmp_config("$section.svm-replace", $replace);
+		tmp_config("$section.svm-uuid", $uuid);
+		$self->{svm} = {
+			source => $src,
+			uuid => $uuid,
+			replace => $replace
+		};
+	}
+
+	my $r = $ra->get_latest_revnum;
+	my $path = $self->{path};
+	my %tried;
+	while (length $path) {
+		unless ($tried{"$self->{url}/$path"}) {
+			return $ra if $self->read_svm_props($ra, $path, $r);
+			$tried{"$self->{url}/$path"} = 1;
+		}
+		$path =~ s#/?[^/]+$##;
+	}
+	die "Path: '$path' should be ''\n" if $path ne '';
+	return $ra if $self->read_svm_props($ra, $path, $r);
+	$tried{"$self->{url}/$path"} = 1;
+
+	if ($ra->{repos_root} eq $self->{url}) {
+		die @err, (map { "  $_\n" } keys %tried), "\n";
+	}
+
+	# nope, make sure we're connected to the repository root:
+	my $ok;
+	my @tried_b;
+	$path = $ra->{svn_path};
+	$ra = Git::SVN::Ra->new($ra->{repos_root});
+	while (length $path) {
+		unless ($tried{"$ra->{url}/$path"}) {
+			$ok = $self->read_svm_props($ra, $path, $r);
+			last if $ok;
+			$tried{"$ra->{url}/$path"} = 1;
+		}
+		$path =~ s#/?[^/]+$##;
+	}
+	die "Path: '$path' should be ''\n" if $path ne '';
+	$ok ||= $self->read_svm_props($ra, $path, $r);
+	$tried{"$ra->{url}/$path"} = 1;
+	if (!$ok) {
+		die @err, (map { "  $_\n" } keys %tried), "\n";
+	}
+	Git::SVN::Ra->new($self->{url});
+}
+
+sub svnsync {
+	my ($self) = @_;
+	return $self->{svnsync} if $self->{svnsync};
+
+	if ($self->no_metadata) {
+		die "Can't have both 'noMetadata' and ",
+		    "'useSvnsyncProps' options set!\n";
+	}
+	if ($self->rewrite_root) {
+		die "Can't have both 'useSvnsyncProps' and 'rewriteRoot' ",
+		    "options set!\n";
+	}
+	if ($self->rewrite_uuid) {
+		die "Can't have both 'useSvnsyncProps' and 'rewriteUUID' ",
+		    "options set!\n";
+	}
+
+	my $svnsync;
+	# see if we have it in our config, first:
+	eval {
+		my $section = "svn-remote.$self->{repo_id}";
+
+		my $url = tmp_config('--get', "$section.svnsync-url");
+		($url) = ($url =~ m{^([a-z\+]+://\S+)$}) or
+		   die "doesn't look right - svn:sync-from-url is '$url'\n";
+
+		my $uuid = tmp_config('--get', "$section.svnsync-uuid");
+		($uuid) = ($uuid =~ m{^([0-9a-f\-]{30,})$}i) or
+		   die "doesn't look right - svn:sync-from-uuid is '$uuid'\n";
+
+		$svnsync = { url => $url, uuid => $uuid }
+	};
+	if ($svnsync && $svnsync->{url} && $svnsync->{uuid}) {
+		return $self->{svnsync} = $svnsync;
+	}
+
+	my $err = "useSvnsyncProps set, but failed to read " .
+	          "svnsync property: svn:sync-from-";
+	my $rp = $self->ra->rev_proplist(0);
+
+	my $url = $rp->{'svn:sync-from-url'} or die $err . "url\n";
+	($url) = ($url =~ m{^([a-z\+]+://\S+)$}) or
+	           die "doesn't look right - svn:sync-from-url is '$url'\n";
+
+	my $uuid = $rp->{'svn:sync-from-uuid'} or die $err . "uuid\n";
+	($uuid) = ($uuid =~ m{^([0-9a-f\-]{30,})$}i) or
+	           die "doesn't look right - svn:sync-from-uuid is '$uuid'\n";
+
+	my $section = "svn-remote.$self->{repo_id}";
+	tmp_config('--add', "$section.svnsync-uuid", $uuid);
+	tmp_config('--add', "$section.svnsync-url", $url);
+	return $self->{svnsync} = { url => $url, uuid => $uuid };
+}
+
+# this allows us to memoize our SVN::Ra UUID locally and avoid a
+# remote lookup (useful for 'git svn log').
+sub ra_uuid {
+	my ($self) = @_;
+	unless ($self->{ra_uuid}) {
+		my $key = "svn-remote.$self->{repo_id}.uuid";
+		my $uuid = eval { tmp_config('--get', $key) };
+		if (!$@ && $uuid && $uuid =~ /^([a-f\d\-]{30,})$/i) {
+			$self->{ra_uuid} = $uuid;
+		} else {
+			die "ra_uuid called without URL\n" unless $self->{url};
+			$self->{ra_uuid} = $self->ra->get_uuid;
+			tmp_config('--add', $key, $self->{ra_uuid});
+		}
+	}
+	$self->{ra_uuid};
+}
+
+sub _set_repos_root {
+	my ($self, $repos_root) = @_;
+	my $k = "svn-remote.$self->{repo_id}.reposRoot";
+	$repos_root ||= $self->ra->{repos_root};
+	tmp_config($k, $repos_root);
+	$repos_root;
+}
+
+sub repos_root {
+	my ($self) = @_;
+	my $k = "svn-remote.$self->{repo_id}.reposRoot";
+	eval { tmp_config('--get', $k) } || $self->_set_repos_root;
+}
+
+sub ra {
+	my ($self) = shift;
+	my $ra = Git::SVN::Ra->new($self->{url});
+	$self->_set_repos_root($ra->{repos_root});
+	if ($self->use_svm_props && !$self->{svm}) {
+		if ($self->no_metadata) {
+			die "Can't have both 'noMetadata' and ",
+			    "'useSvmProps' options set!\n";
+		} elsif ($self->use_svnsync_props) {
+			die "Can't have both 'useSvnsyncProps' and ",
+			    "'useSvmProps' options set!\n";
+		}
+		$ra = $self->_set_svm_vars($ra);
+		$self->{-want_revprops} = 1;
+	}
+	$ra;
+}
+
+# prop_walk(PATH, REV, SUB)
+# -------------------------
+# Recursively traverse PATH at revision REV and invoke SUB for each
+# directory that contains a SVN property.  SUB will be invoked as
+# follows:  &SUB(gs, path, props);  where `gs' is this instance of
+# Git::SVN, `path' the path to the directory where the properties
+# `props' were found.  The `path' will be relative to point of checkout,
+# that is, if url://repo/trunk is the current Git branch, and that
+# directory contains a sub-directory `d', SUB will be invoked with `/d/'
+# as `path' (note the trailing `/').
+sub prop_walk {
+	my ($self, $path, $rev, $sub) = @_;
+
+	$path =~ s#^/##;
+	my ($dirent, undef, $props) = $self->ra->get_dir($path, $rev);
+	$path =~ s#^/*#/#g;
+	my $p = $path;
+	# Strip the irrelevant part of the path.
+	$p =~ s#^/+\Q$self->{path}\E(/|$)#/#;
+	# Ensure the path is terminated by a `/'.
+	$p =~ s#/*$#/#;
+
+	# The properties contain all the internal SVN stuff nobody
+	# (usually) cares about.
+	my $interesting_props = 0;
+	foreach (keys %{$props}) {
+		# If it doesn't start with `svn:', it must be a
+		# user-defined property.
+		++$interesting_props and next if $_ !~ /^svn:/;
+		# FIXME: Fragile, if SVN adds new public properties,
+		# this needs to be updated.
+		++$interesting_props if /^svn:(?:ignore|keywords|executable
+		                                 |eol-style|mime-type
+						 |externals|needs-lock)$/x;
+	}
+	&$sub($self, $p, $props) if $interesting_props;
+
+	foreach (sort keys %$dirent) {
+		next if $dirent->{$_}->{kind} != $SVN::Node::dir;
+		$self->prop_walk($self->{path} . $p . $_, $rev, $sub);
+	}
+}
+
+sub last_rev { ($_[0]->last_rev_commit)[0] }
+sub last_commit { ($_[0]->last_rev_commit)[1] }
+
+# returns the newest SVN revision number and newest commit SHA1
+sub last_rev_commit {
+	my ($self) = @_;
+	if (defined $self->{last_rev} && defined $self->{last_commit}) {
+		return ($self->{last_rev}, $self->{last_commit});
+	}
+	my $c = ::verify_ref($self->refname.'^0');
+	if ($c && !$self->use_svm_props && !$self->no_metadata) {
+		my $rev = (::cmt_metadata($c))[1];
+		if (defined $rev) {
+			($self->{last_rev}, $self->{last_commit}) = ($rev, $c);
+			return ($rev, $c);
+		}
+	}
+	my $map_path = $self->map_path;
+	unless (-e $map_path) {
+		($self->{last_rev}, $self->{last_commit}) = (undef, undef);
+		return (undef, undef);
+	}
+	my ($rev, $commit) = $self->rev_map_max(1);
+	($self->{last_rev}, $self->{last_commit}) = ($rev, $commit);
+	return ($rev, $commit);
+}
+
+sub get_fetch_range {
+	my ($self, $min, $max) = @_;
+	$max ||= $self->ra->get_latest_revnum;
+	$min ||= $self->rev_map_max;
+	(++$min, $max);
+}
+
+sub tmp_config {
+	my (@args) = @_;
+	my $old_def_config = "$ENV{GIT_DIR}/svn/config";
+	my $config = "$ENV{GIT_DIR}/svn/.metadata";
+	if (! -f $config && -f $old_def_config) {
+		rename $old_def_config, $config or
+		       die "Failed rename $old_def_config => $config: $!\n";
+	}
+	my $old_config = $ENV{GIT_CONFIG};
+	$ENV{GIT_CONFIG} = $config;
+	$@ = undef;
+	my @ret = eval {
+		unless (-f $config) {
+			mkfile($config);
+			open my $fh, '>', $config or
+			    die "Can't open $config: $!\n";
+			print $fh "; This file is used internally by ",
+			          "git-svn\n" or die
+				  "Couldn't write to $config: $!\n";
+			print $fh "; You should not have to edit it\n" or
+			      die "Couldn't write to $config: $!\n";
+			close $fh or die "Couldn't close $config: $!\n";
+		}
+		command('config', @args);
+	};
+	my $err = $@;
+	if (defined $old_config) {
+		$ENV{GIT_CONFIG} = $old_config;
+	} else {
+		delete $ENV{GIT_CONFIG};
+	}
+	die $err if $err;
+	wantarray ? @ret : $ret[0];
+}
+
+sub tmp_index_do {
+	my ($self, $sub) = @_;
+	my $old_index = $ENV{GIT_INDEX_FILE};
+	$ENV{GIT_INDEX_FILE} = $self->{index};
+	$@ = undef;
+	my @ret = eval {
+		my ($dir, $base) = ($self->{index} =~ m#^(.*?)/?([^/]+)$#);
+		mkpath([$dir]) unless -d $dir;
+		&$sub;
+	};
+	my $err = $@;
+	if (defined $old_index) {
+		$ENV{GIT_INDEX_FILE} = $old_index;
+	} else {
+		delete $ENV{GIT_INDEX_FILE};
+	}
+	die $err if $err;
+	wantarray ? @ret : $ret[0];
+}
+
+sub assert_index_clean {
+	my ($self, $treeish) = @_;
+
+	$self->tmp_index_do(sub {
+		command_noisy('read-tree', $treeish) unless -e $self->{index};
+		my $x = command_oneline('write-tree');
+		my ($y) = (command(qw/cat-file commit/, $treeish) =~
+		           /^tree ($::sha1)/mo);
+		return if $y eq $x;
+
+		warn "Index mismatch: $y != $x\nrereading $treeish\n";
+		unlink $self->{index} or die "unlink $self->{index}: $!\n";
+		command_noisy('read-tree', $treeish);
+		$x = command_oneline('write-tree');
+		if ($y ne $x) {
+			fatal "trees ($treeish) $y != $x\n",
+			      "Something is seriously wrong...";
+		}
+	});
+}
+
+sub get_commit_parents {
+	my ($self, $log_entry) = @_;
+	my (%seen, @ret, @tmp);
+	# legacy support for 'set-tree'; this is only used by set_tree_cb:
+	if (my $ip = $self->{inject_parents}) {
+		if (my $commit = delete $ip->{$log_entry->{revision}}) {
+			push @tmp, $commit;
+		}
+	}
+	if (my $cur = ::verify_ref($self->refname.'^0')) {
+		push @tmp, $cur;
+	}
+	if (my $ipd = $self->{inject_parents_dcommit}) {
+		if (my $commit = delete $ipd->{$log_entry->{revision}}) {
+			push @tmp, @$commit;
+		}
+	}
+	push @tmp, $_ foreach (@{$log_entry->{parents}}, @tmp);
+	while (my $p = shift @tmp) {
+		next if $seen{$p};
+		$seen{$p} = 1;
+		push @ret, $p;
+	}
+	@ret;
+}
+
+sub rewrite_root {
+	my ($self) = @_;
+	return $self->{-rewrite_root} if exists $self->{-rewrite_root};
+	my $k = "svn-remote.$self->{repo_id}.rewriteRoot";
+	my $rwr = eval { command_oneline(qw/config --get/, $k) };
+	if ($rwr) {
+		$rwr =~ s#/+$##;
+		if ($rwr !~ m#^[a-z\+]+://#) {
+			die "$rwr is not a valid URL (key: $k)\n";
+		}
+	}
+	$self->{-rewrite_root} = $rwr;
+}
+
+sub rewrite_uuid {
+	my ($self) = @_;
+	return $self->{-rewrite_uuid} if exists $self->{-rewrite_uuid};
+	my $k = "svn-remote.$self->{repo_id}.rewriteUUID";
+	my $rwid = eval { command_oneline(qw/config --get/, $k) };
+	if ($rwid) {
+		$rwid =~ s#/+$##;
+		if ($rwid !~ m#^[a-f0-9]{8}-(?:[a-f0-9]{4}-){3}[a-f0-9]{12}$#) {
+			die "$rwid is not a valid UUID (key: $k)\n";
+		}
+	}
+	$self->{-rewrite_uuid} = $rwid;
+}
+
+sub metadata_url {
+	my ($self) = @_;
+	($self->rewrite_root || $self->{url}) .
+	   (length $self->{path} ? '/' . $self->{path} : '');
+}
+
+sub full_url {
+	my ($self) = @_;
+	$self->{url} . (length $self->{path} ? '/' . $self->{path} : '');
+}
+
+sub full_pushurl {
+	my ($self) = @_;
+	if ($self->{pushurl}) {
+		return $self->{pushurl} . (length $self->{path} ? '/' .
+		       $self->{path} : '');
+	} else {
+		return $self->full_url;
+	}
+}
+
+sub set_commit_header_env {
+	my ($log_entry) = @_;
+	my %env;
+	foreach my $ned (qw/NAME EMAIL DATE/) {
+		foreach my $ac (qw/AUTHOR COMMITTER/) {
+			$env{"GIT_${ac}_${ned}"} = $ENV{"GIT_${ac}_${ned}"};
+		}
+	}
+
+	$ENV{GIT_AUTHOR_NAME} = $log_entry->{name};
+	$ENV{GIT_AUTHOR_EMAIL} = $log_entry->{email};
+	$ENV{GIT_AUTHOR_DATE} = $ENV{GIT_COMMITTER_DATE} = $log_entry->{date};
+
+	$ENV{GIT_COMMITTER_NAME} = (defined $log_entry->{commit_name})
+						? $log_entry->{commit_name}
+						: $log_entry->{name};
+	$ENV{GIT_COMMITTER_EMAIL} = (defined $log_entry->{commit_email})
+						? $log_entry->{commit_email}
+						: $log_entry->{email};
+	\%env;
+}
+
+sub restore_commit_header_env {
+	my ($env) = @_;
+	foreach my $ned (qw/NAME EMAIL DATE/) {
+		foreach my $ac (qw/AUTHOR COMMITTER/) {
+			my $k = "GIT_${ac}_${ned}";
+			if (defined $env->{$k}) {
+				$ENV{$k} = $env->{$k};
+			} else {
+				delete $ENV{$k};
+			}
+		}
+	}
+}
+
+sub gc {
+	command_noisy('gc', '--auto');
+};
+
+sub do_git_commit {
+	my ($self, $log_entry) = @_;
+	my $lr = $self->last_rev;
+	if (defined $lr && $lr >= $log_entry->{revision}) {
+		die "Last fetched revision of ", $self->refname,
+		    " was r$lr, but we are about to fetch: ",
+		    "r$log_entry->{revision}!\n";
+	}
+	if (my $c = $self->rev_map_get($log_entry->{revision})) {
+		croak "$log_entry->{revision} = $c already exists! ",
+		      "Why are we refetching it?\n";
+	}
+	my $old_env = set_commit_header_env($log_entry);
+	my $tree = $log_entry->{tree};
+	if (!defined $tree) {
+		$tree = $self->tmp_index_do(sub {
+		                            command_oneline('write-tree') });
+	}
+	die "Tree is not a valid sha1: $tree\n" if $tree !~ /^$::sha1$/o;
+
+	my @exec = ('git', 'commit-tree', $tree);
+	foreach ($self->get_commit_parents($log_entry)) {
+		push @exec, '-p', $_;
+	}
+	defined(my $pid = open3(my $msg_fh, my $out_fh, '>&STDERR', @exec))
+	                                                           or croak $!;
+	binmode $msg_fh;
+
+	# we always get UTF-8 from SVN, but we may want our commits in
+	# a different encoding.
+	if (my $enc = Git::config('i18n.commitencoding')) {
+		require Encode;
+		Encode::from_to($log_entry->{log}, 'UTF-8', $enc);
+	}
+	print $msg_fh $log_entry->{log} or croak $!;
+	restore_commit_header_env($old_env);
+	unless ($self->no_metadata) {
+		print $msg_fh "\ngit-svn-id: $log_entry->{metadata}\n"
+		              or croak $!;
+	}
+	$msg_fh->flush == 0 or croak $!;
+	close $msg_fh or croak $!;
+	chomp(my $commit = do { local $/; <$out_fh> });
+	close $out_fh or croak $!;
+	waitpid $pid, 0;
+	croak $? if $?;
+	if ($commit !~ /^$::sha1$/o) {
+		die "Failed to commit, invalid sha1: $commit\n";
+	}
+
+	$self->rev_map_set($log_entry->{revision}, $commit, 1);
+
+	$self->{last_rev} = $log_entry->{revision};
+	$self->{last_commit} = $commit;
+	print "r$log_entry->{revision}" unless $::_q > 1;
+	if (defined $log_entry->{svm_revision}) {
+		 print " (\@$log_entry->{svm_revision})" unless $::_q > 1;
+		 $self->rev_map_set($log_entry->{svm_revision}, $commit,
+		                   0, $self->svm_uuid);
+	}
+	print " = $commit ($self->{ref_id})\n" unless $::_q > 1;
+	if (--$_gc_nr == 0) {
+		$_gc_nr = $_gc_period;
+		gc();
+	}
+	return $commit;
+}
+
+sub match_paths {
+	my ($self, $paths, $r) = @_;
+	return 1 if $self->{path} eq '';
+	if (my $path = $paths->{"/$self->{path}"}) {
+		return ($path->{action} eq 'D') ? 0 : 1;
+	}
+	$self->{path_regex} ||= qr/^\/\Q$self->{path}\E\//;
+	if (grep /$self->{path_regex}/, keys %$paths) {
+		return 1;
+	}
+	my $c = '';
+	foreach (split m#/#, $self->{path}) {
+		$c .= "/$_";
+		next unless ($paths->{$c} &&
+		             ($paths->{$c}->{action} =~ /^[AR]$/));
+		if ($self->ra->check_path($self->{path}, $r) ==
+		    $SVN::Node::dir) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+sub find_parent_branch {
+	my ($self, $paths, $rev) = @_;
+	return undef unless $self->follow_parent;
+	unless (defined $paths) {
+		my $err_handler = $SVN::Error::handler;
+		$SVN::Error::handler = \&Git::SVN::Ra::skip_unknown_revs;
+		$self->ra->get_log([$self->{path}], $rev, $rev, 0, 1, 1,
+				   sub { $paths = $_[0] });
+		$SVN::Error::handler = $err_handler;
+	}
+	return undef unless defined $paths;
+
+	# look for a parent from another branch:
+	my @b_path_components = split m#/#, $self->{path};
+	my @a_path_components;
+	my $i;
+	while (@b_path_components) {
+		$i = $paths->{'/'.join('/', @b_path_components)};
+		last if $i && defined $i->{copyfrom_path};
+		unshift(@a_path_components, pop(@b_path_components));
+	}
+	return undef unless defined $i && defined $i->{copyfrom_path};
+	my $branch_from = $i->{copyfrom_path};
+	if (@a_path_components) {
+		print STDERR "branch_from: $branch_from => ";
+		$branch_from .= '/'.join('/', @a_path_components);
+		print STDERR $branch_from, "\n";
+	}
+	my $r = $i->{copyfrom_rev};
+	my $repos_root = $self->ra->{repos_root};
+	my $url = $self->ra->{url};
+	my $new_url = $url . $branch_from;