From 3397f9df53092871de2c33c143f1f4413654c40d Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Thu, 16 Feb 2006 01:24:16 -0800 Subject: Introducing contrib/git-svn. diff --git a/contrib/git-svn/git-svn b/contrib/git-svn/git-svn new file mode 100755 index 0000000..62fc14f --- /dev/null +++ b/contrib/git-svn/git-svn @@ -0,0 +1,770 @@ +#!/usr/bin/env perl +use warnings; +use strict; +use vars qw/ $AUTHOR $VERSION + $SVN_URL $SVN_INFO $SVN_WC + $GIT_SVN_INDEX $GIT_SVN + $GIT_DIR $REV_DIR/; +$AUTHOR = 'Eric Wong '; +$VERSION = '0.9.0'; +$GIT_DIR = $ENV{GIT_DIR} || "$ENV{PWD}/.git"; +$GIT_SVN = $ENV{GIT_SVN_ID} || 'git-svn'; +$GIT_SVN_INDEX = "$GIT_DIR/$GIT_SVN/index"; +$ENV{GIT_DIR} ||= $GIT_DIR; +$SVN_URL = undef; +$REV_DIR = "$GIT_DIR/$GIT_SVN/revs"; +$SVN_WC = "$GIT_DIR/$GIT_SVN/tree"; + +# make sure the svn binary gives consistent output between locales and TZs: +$ENV{TZ} = 'UTC'; +$ENV{LC_ALL} = 'C'; + +# If SVN:: library support is added, please make the dependencies +# optional and preserve the capability to use the command-line client. +# See what I do with XML::Simple to make the dependency optional. +use Carp qw/croak/; +use IO::File qw//; +use File::Basename qw/dirname basename/; +use File::Path qw/mkpath/; +use Getopt::Long qw/:config gnu_getopt no_ignore_case auto_abbrev/; +use File::Spec qw//; +my $sha1 = qr/[a-f\d]{40}/; +my $sha1_short = qr/[a-f\d]{6,40}/; +my ($_revision,$_stdin,$_no_ignore_ext,$_no_stop_copy,$_help,$_rmdir,$_edit); + +GetOptions( 'revision|r=s' => \$_revision, + 'no-ignore-externals' => \$_no_ignore_ext, + 'stdin|' => \$_stdin, + 'edit|e' => \$_edit, + 'rmdir' => \$_rmdir, + 'help|H|h' => \$_help, + 'no-stop-copy' => \$_no_stop_copy ); +my %cmd = ( + fetch => [ \&fetch, "Download new revisions from SVN" ], + init => [ \&init, "Initialize and fetch (import)"], + commit => [ \&commit, "Commit git revisions to SVN" ], + rebuild => [ \&rebuild, "Rebuild git-svn metadata (after git clone)" ], + help => [ \&usage, "Show help" ], +); +my $cmd; +for (my $i = 0; $i < @ARGV; $i++) { + if (defined $cmd{$ARGV[$i]}) { + $cmd = $ARGV[$i]; + splice @ARGV, $i, 1; + last; + } +}; + +# we may be called as git-svn-(command), or git-svn(command). +foreach (keys %cmd) { + if (/git\-svn\-?($_)(?:\.\w+)?$/) { + $cmd = $1; + last; + } +} +usage(0) if $_help; +usage(1) unless (defined $cmd); +svn_check_ignore_externals(); +$cmd{$cmd}->[0]->(@ARGV); +exit 0; + +####################### primary functions ###################### +sub usage { + my $exit = shift || 0; + my $fd = $exit ? \*STDERR : \*STDOUT; + print $fd <<""; +git-svn - bidirectional operations between a single Subversion tree and git +Usage: $0 [options] [arguments]\n +Available commands: + + foreach (sort keys %cmd) { + print $fd ' ',pack('A10',$_),$cmd{$_}->[1],"\n"; + } + print $fd <<""; +\nGIT_SVN_ID may be set in the environment to an arbitrary identifier if +you're tracking multiple SVN branches/repositories in one git repository +and want to keep them separate. + + exit $exit; +} + +sub rebuild { + $SVN_URL = shift or undef; + my $repo_uuid; + my $newest_rev = 0; + + my $pid = open(my $rev_list,'-|'); + defined $pid or croak $!; + if ($pid == 0) { + exec("git-rev-list","$GIT_SVN-HEAD") or croak $!; + } + my $first; + while (<$rev_list>) { + chomp; + my $c = $_; + croak "Non-SHA1: $c\n" unless $c =~ /^$sha1$/o; + my @commit = grep(/^git-svn-id: /,`git-cat-file commit $c`); + next if (!@commit); # skip merges + my $id = $commit[$#commit]; + my ($url, $rev, $uuid) = ($id =~ /^git-svn-id:\s(\S+?)\@(\d+) + \s([a-f\d\-]+)$/x); + if (!$rev || !$uuid || !$url) { + # some of the original repositories I made had + # indentifiers like this: + ($rev, $uuid) = ($id =~/^git-svn-id:\s(\d+) + \@([a-f\d\-]+)/x); + if (!$rev || !$uuid) { + croak "Unable to extract revision or UUID from ", + "$c, $id\n"; + } + } + print "r$rev = $c\n"; + unless (defined $first) { + if (!$SVN_URL && !$url) { + croak "SVN repository location required: $url\n"; + } + $SVN_URL ||= $url; + $repo_uuid = setup_git_svn(); + $first = $rev; + } + if ($uuid ne $repo_uuid) { + croak "Repository UUIDs do not match!\ngot: $uuid\n", + "expected: $repo_uuid\n"; + } + assert_revision_eq_or_unknown($rev, $c); + sys('git-update-ref',"$GIT_SVN/revs/$rev",$c); + $newest_rev = $rev if ($rev > $newest_rev); + } + close $rev_list or croak $?; + if (!chdir $SVN_WC) { + my @svn_co = ('svn','co',"-r$first"); + push @svn_co, '--ignore-externals' unless $_no_ignore_ext; + sys(@svn_co, $SVN_URL, $SVN_WC); + chdir $SVN_WC or croak $!; + } + + $pid = fork; + defined $pid or croak $!; + if ($pid == 0) { + my @svn_up = qw(svn up); + push @svn_up, '--ignore-externals' unless $_no_ignore_ext; + sys(@svn_up,"-r$newest_rev"); + $ENV{GIT_INDEX_FILE} = $GIT_SVN_INDEX; + git_addremove(); + exec('git-write-tree'); + } + waitpid $pid, 0; +} + +sub init { + $SVN_URL = shift or croak "SVN repository location required\n"; + unless (-d $GIT_DIR) { + sys('git-init-db'); + } + setup_git_svn(); +} + +sub fetch { + my (@parents) = @_; + $SVN_URL ||= file_to_s("$GIT_DIR/$GIT_SVN/info/url"); + my @log_args = -d $SVN_WC ? ($SVN_WC) : ($SVN_URL); + if (-d $SVN_WC && !$_revision) { + $_revision = 'BASE:HEAD'; + } + push @log_args, "-r$_revision" if $_revision; + push @log_args, '--stop-on-copy' unless $_no_stop_copy; + + eval { require XML::Simple or croak $! }; + my $svn_log = $@ ? svn_log_raw(@log_args) : svn_log_xml(@log_args); + + my $base = shift @$svn_log or croak "No base revision!\n"; + my $last_commit = undef; + unless (-d $SVN_WC) { + my @svn_co = ('svn','co',"-r$base->{revision}"); + push @svn_co,'--ignore-externals' unless $_no_ignore_ext; + sys(@svn_co, $SVN_URL, $SVN_WC); + chdir $SVN_WC or croak $!; + $last_commit = git_commit($base, @parents); + unless (-f "$GIT_DIR/refs/heads/master") { + sys(qw(git-update-ref refs/heads/master),$last_commit); + } + assert_svn_wc_clean($base->{revision}, $last_commit); + } else { + chdir $SVN_WC or croak $!; + $last_commit = file_to_s("$REV_DIR/$base->{revision}"); + } + my @svn_up = qw(svn up); + push @svn_up, '--ignore-externals' unless $_no_ignore_ext; + my $last_rev = $base->{revision}; + foreach my $log_msg (@$svn_log) { + assert_svn_wc_clean($last_rev, $last_commit); + $last_rev = $log_msg->{revision}; + sys(@svn_up,"-r$last_rev"); + $last_commit = git_commit($log_msg, $last_commit, @parents); + } + assert_svn_wc_clean($last_rev, $last_commit); + return pop @$svn_log; +} + +sub commit { + my (@commits) = @_; + if ($_stdin || !@commits) { + print "Reading from stdin...\n"; + @commits = (); + while () { + if (/^([a-f\d]{6,40})\b/) { + unshift @commits, $1; + } + } + } + my @revs; + foreach (@commits) { + push @revs, (safe_qx('git-rev-parse',$_)); + } + chomp @revs; + + fetch(); + chdir $SVN_WC or croak $!; + my $svn_current_rev = svn_info('.')->{'Last Changed Rev'}; + foreach my $c (@revs) { + print "Committing $c\n"; + svn_checkout_tree($svn_current_rev, $c); + $svn_current_rev = svn_commit_tree($svn_current_rev, $c); + } + print "Done committing ",scalar @revs," revisions to SVN\n"; + +} + +########################### utility functions ######################### + +sub setup_git_svn { + defined $SVN_URL or croak "SVN repository location required\n"; + unless (-d $GIT_DIR) { + croak "GIT_DIR=$GIT_DIR does not exist!\n"; + } + mkpath(["$GIT_DIR/$GIT_SVN"]); + mkpath(["$GIT_DIR/$GIT_SVN/info"]); + mkpath([$REV_DIR]); + s_to_file($SVN_URL,"$GIT_DIR/$GIT_SVN/info/url"); + my $uuid = svn_info($SVN_URL)->{'Repository UUID'} or + croak "Repository UUID unreadable\n"; + s_to_file($uuid,"$GIT_DIR/$GIT_SVN/info/uuid"); + + open my $fd, '>>', "$GIT_DIR/$GIT_SVN/info/exclude" or croak $!; + print $fd '.svn',"\n"; + close $fd or croak $!; + return $uuid; +} + +sub assert_svn_wc_clean { + my ($svn_rev, $commit) = @_; + croak "$svn_rev is not an integer!\n" unless ($svn_rev =~ /^\d+$/); + croak "$commit is not a sha1!\n" unless ($commit =~ /^$sha1$/o); + my $svn_info = svn_info('.'); + if ($svn_rev != $svn_info->{'Last Changed Rev'}) { + croak "Expected r$svn_rev, got r", + $svn_info->{'Last Changed Rev'},"\n"; + } + my @status = grep(!/^Performing status on external/,(`svn status`)); + @status = grep(!/^\s*$/,@status); + if (scalar @status) { + print STDERR "Tree ($SVN_WC) is not clean:\n"; + print STDERR $_ foreach @status; + croak; + } + my ($tree_a) = grep(/^tree $sha1$/o,`git-cat-file commit $commit`); + $tree_a =~ s/^tree //; + chomp $tree_a; + chomp(my $tree_b = `GIT_INDEX_FILE=$GIT_SVN_INDEX git-write-tree`); + if ($tree_a ne $tree_b) { + croak "$svn_rev != $commit, $tree_a != $tree_b\n"; + } +} + +sub parse_diff_tree { + my $diff_fh = shift; + local $/ = "\0"; + my $state = 'meta'; + my @mods; + while (<$diff_fh>) { + chomp $_; # this gets rid of the trailing "\0" + print $_,"\n"; + if ($state eq 'meta' && /^:(\d{6})\s(\d{6})\s + $sha1\s($sha1)\s([MTCRAD])\d*$/xo) { + push @mods, { mode_a => $1, mode_b => $2, + sha1_b => $3, chg => $4 }; + if ($4 =~ /^(?:C|R)$/) { + $state = 'file_a'; + } else { + $state = 'file_b'; + } + } elsif ($state eq 'file_a') { + my $x = $mods[$#mods] or croak __LINE__,": Empty array\n"; + if ($x->{chg} !~ /^(?:C|R)$/) { + croak __LINE__,": Error parsing $_, $x->{chg}\n"; + } + $x->{file_a} = $_; + $state = 'file_b'; + } elsif ($state eq 'file_b') { + my $x = $mods[$#mods] or croak __LINE__,": Empty array\n"; + if (exists $x->{file_a} && $x->{chg} !~ /^(?:C|R)$/) { + croak __LINE__,": Error parsing $_, $x->{chg}\n"; + } + if (!exists $x->{file_a} && $x->{chg} =~ /^(?:C|R)$/) { + croak __LINE__,": Error parsing $_, $x->{chg}\n"; + } + $x->{file_b} = $_; + $state = 'meta'; + } else { + croak __LINE__,": Error parsing $_\n"; + } + } + close $diff_fh or croak $!; + return \@mods; +} + +sub svn_check_prop_executable { + my $m = shift; + if ($m->{mode_b} =~ /755$/ && $m->{mode_a} !~ /755$/) { + sys(qw(svn propset svn:executable 1), $m->{file_b}); + } elsif ($m->{mode_b} !~ /755$/ && $m->{mode_a} =~ /755$/) { + sys(qw(svn propdel svn:executable), $m->{file_b}); + } +} + +sub svn_ensure_parent_path { + my $dir_b = dirname(shift); + svn_ensure_parent_path($dir_b) if ($dir_b ne File::Spec->curdir); + mkpath([$dir_b]) unless (-d $dir_b); + sys(qw(svn add -N), $dir_b) unless (-d "$dir_b/.svn"); +} + +sub svn_checkout_tree { + my ($svn_rev, $commit) = @_; + my $from = file_to_s("$REV_DIR/$svn_rev"); + assert_svn_wc_clean($svn_rev,$from); + print "diff-tree '$from' '$commit'\n"; + my $pid = open my $diff_fh, '-|'; + defined $pid or croak $!; + if ($pid == 0) { + exec(qw(git-diff-tree -z -r -C), $from, $commit) or croak $!; + } + my $mods = parse_diff_tree($diff_fh); + unless (@$mods) { + # git can do empty commits, SVN doesn't allow it... + return $svn_rev; + } + my %rm; + foreach my $m (@$mods) { + if ($m->{chg} eq 'C') { + svn_ensure_parent_path( $m->{file_b} ); + sys(qw(svn cp), $m->{file_a}, $m->{file_b}); + blob_to_file( $m->{sha1_b}, $m->{file_b}); + svn_check_prop_executable($m); + } elsif ($m->{chg} eq 'D') { + $rm{dirname $m->{file_b}}->{basename $m->{file_b}} = 1; + sys(qw(svn rm --force), $m->{file_b}); + } elsif ($m->{chg} eq 'R') { + svn_ensure_parent_path( $m->{file_b} ); + sys(qw(svn mv --force), $m->{file_a}, $m->{file_b}); + blob_to_file( $m->{sha1_b}, $m->{file_b}); + svn_check_prop_executable($m); + $rm{dirname $m->{file_a}}->{basename $m->{file_a}} = 1; + } elsif ($m->{chg} eq 'M') { + if ($m->{mode_b} =~ /^120/ && $m->{mode_a} =~ /^120/) { + unlink $m->{file_b} or croak $!; + blob_to_symlink($m->{sha1_b}, $m->{file_b}); + } else { + blob_to_file($m->{sha1_b}, $m->{file_b}); + } + svn_check_prop_executable($m); + } elsif ($m->{chg} eq 'T') { + sys(qw(svn rm --force),$m->{file_b}); + if ($m->{mode_b} =~ /^120/ && $m->{mode_a} =~ /^100/) { + blob_to_symlink($m->{sha1_b}, $m->{file_b}); + } else { + blob_to_file($m->{sha1_b}, $m->{file_b}); + } + svn_check_prop_executable($m); + sys(qw(svn add --force), $m->{file_b}); + } elsif ($m->{chg} eq 'A') { + svn_ensure_parent_path( $m->{file_b} ); + blob_to_file( $m->{sha1_b}, $m->{file_b}); + if ($m->{mode_b} =~ /755$/) { + chmod 0755, $m->{file_b}; + } + sys(qw(svn add --force), $m->{file_b}); + } else { + croak "Invalid chg: $m->{chg}\n"; + } + } + if ($_rmdir) { + my $old_index = $ENV{GIT_INDEX_FILE}; + $ENV{GIT_INDEX_FILE} = $GIT_SVN_INDEX; + foreach my $dir (keys %rm) { + my $files = $rm{$dir}; + my @files; + foreach (safe_qx('svn','ls',$dir)) { + chomp; + push @files, $_ unless $files->{$_}; + } + sys(qw(svn rm),$dir) unless @files; + } + if ($old_index) { + $ENV{GIT_INDEX_FILE} = $old_index; + } else { + delete $ENV{GIT_INDEX_FILE}; + } + } +} + +sub svn_commit_tree { + my ($svn_rev, $commit) = @_; + my $commit_msg = "$GIT_DIR/$GIT_SVN/.svn-commit.tmp.$$"; + open my $msg, '>', $commit_msg or croak $!; + + chomp(my $type = `git-cat-file -t $commit`); + if ($type eq 'commit') { + my $pid = open my $msg_fh, '-|'; + defined $pid or croak $!; + + if ($pid == 0) { + exec(qw(git-cat-file commit), $commit) or croak $!; + } + my $in_msg = 0; + while (<$msg_fh>) { + if (!$in_msg) { + $in_msg = 1 if (/^\s*$/); + } else { + print $msg $_ or croak $!; + } + } + close $msg_fh or croak $!; + } + close $msg or croak $!; + + if ($_edit || ($type eq 'tree')) { + my $editor = $ENV{VISUAL} || $ENV{EDITOR} || 'vi'; + system($editor, $commit_msg); + } + my @ci_output = safe_qx(qw(svn commit -F),$commit_msg); + my ($committed) = grep(/^Committed revision \d+\./,@ci_output); + unlink $commit_msg; + defined $committed or croak + "Commit output failed to parse committed revision!\n", + join("\n",@ci_output),"\n"; + my ($rev_committed) = ($committed =~ /^Committed revision (\d+)\./); + + # resync immediately + my @svn_up = (qw(svn up), "-r$svn_rev"); + push @svn_up, '--ignore-externals' unless $_no_ignore_ext; + sys(@svn_up); + return fetch("$rev_committed=$commit")->{revision}; +} + +sub svn_log_xml { + my (@log_args) = @_; + my $log_fh = IO::File->new_tmpfile or croak $!; + + my $pid = fork; + defined $pid or croak $!; + + if ($pid == 0) { + open STDOUT, '>&', $log_fh or croak $!; + exec (qw(svn log --xml), @log_args) or croak $! + } + + waitpid $pid, 0; + croak $? if $?; + + seek $log_fh, 0, 0; + my @svn_log; + my $log = XML::Simple::XMLin( $log_fh, + ForceArray => ['path','revision','logentry'], + KeepRoot => 0, + KeyAttr => { logentry => '+revision', + paths => '+path' }, + )->{logentry}; + foreach my $r (sort {$a <=> $b} keys %$log) { + my $log_msg = $log->{$r}; + my ($Y,$m,$d,$H,$M,$S) = ($log_msg->{date} =~ + /(\d{4})\-(\d\d)\-(\d\d)T + (\d\d)\:(\d\d)\:(\d\d)\.\d+Z$/x) + or croak "Failed to parse date: ", + $log->{$r}->{date}; + $log_msg->{date} = "+0000 $Y-$m-$d $H:$M:$S"; + + # XML::Simple can't handle as a string: + if (ref $log_msg->{msg} eq 'HASH') { + $log_msg->{msg} = "\n"; + } else { + $log_msg->{msg} .= "\n"; + } + push @svn_log, $log->{$r}; + } + return \@svn_log; +} + +sub svn_log_raw { + my (@log_args) = @_; + my $pid = open my $log_fh,'-|'; + defined $pid or croak $!; + + if ($pid == 0) { + exec (qw(svn log), @log_args) or croak $! + } + + my @svn_log; + my $state; + while (<$log_fh>) { + chomp; + if (/^\-{72}$/) { + $state = 'rev'; + + # if we have an empty log message, put something there: + if (@svn_log) { + $svn_log[0]->{msg} ||= "\n"; + } + next; + } + if ($state eq 'rev' && s/^r(\d+)\s*\|\s*//) { + my $rev = $1; + my ($author, $date) = split(/\s*\|\s*/, $_, 2); + my ($Y,$m,$d,$H,$M,$S,$tz) = ($date =~ + /(\d{4})\-(\d\d)\-(\d\d)\s + (\d\d)\:(\d\d)\:(\d\d)\s([\-\+]\d+)/x) + or croak "Failed to parse date: $date\n"; + my %log_msg = ( revision => $rev, + date => "$tz $Y-$m-$d $H:$M:$S", + author => $author, + msg => '' ); + unshift @svn_log, \%log_msg; + $state = 'msg_start'; + next; + } + # skip the first blank line of the message: + if ($state eq 'msg_start' && /^$/) { + $state = 'msg'; + } elsif ($state eq 'msg') { + $svn_log[0]->{msg} .= $_."\n"; + } + } + close $log_fh or croak $?; + return \@svn_log; +} + +sub svn_info { + my $url = shift || $SVN_URL; + + my $pid = open my $info_fh, '-|'; + defined $pid or croak $!; + + if ($pid == 0) { + exec(qw(svn info),$url) or croak $!; + } + + my $ret = {}; + # only single-lines seem to exist in svn info output + while (<$info_fh>) { + chomp $_; + if (m#^([^:]+)\s*:\s*(\S*)$#) { + $ret->{$1} = $2; + push @{$ret->{-order}}, $1; + } + } + close $info_fh or croak $!; + return $ret; +} + +sub sys { system(@_) == 0 or croak $? } + +sub git_addremove { + system( "git-ls-files -z --others ". + "'--exclude-from=$GIT_DIR/$GIT_SVN/info/exclude'". + "| git-update-index --add -z --stdin; ". + "git-ls-files -z --deleted ". + "| git-update-index --remove -z --stdin; ". + "git-ls-files -z --modified". + "| git-update-index -z --stdin") == 0 or croak $? +} + +sub s_to_file { + my ($str, $file, $mode) = @_; + open my $fd,'>',$file or croak $!; + print $fd $str,"\n" or croak $!; + close $fd or croak $!; + chmod ($mode &~ umask, $file) if (defined $mode); +} + +sub file_to_s { + my $file = shift; + open my $fd,'<',$file or croak "$!: file: $file\n"; + local $/; + my $ret = <$fd>; + close $fd or croak $!; + $ret =~ s/\s*$//s; + return $ret; +} + +sub assert_revision_unknown { + my $revno = shift; + if (-f "$REV_DIR/$revno") { + croak "$REV_DIR/$revno already exists! ", + "Why are we refetching it?"; + } +} + +sub assert_revision_eq_or_unknown { + my ($revno, $commit) = @_; + if (-f "$REV_DIR/$revno") { + my $current = file_to_s("$REV_DIR/$revno"); + if ($commit ne $current) { + croak "$REV_DIR/$revno already exists!\n", + "current: $current\nexpected: $commit\n"; + } + return; + } +} + +sub git_commit { + my ($log_msg, @parents) = @_; + assert_revision_unknown($log_msg->{revision}); + my $out_fh = IO::File->new_tmpfile or croak $!; + my $info = svn_info('.'); + my $uuid = $info->{'Repository UUID'}; + defined $uuid or croak "Unable to get Repository UUID\n"; + + # commit parents can be conditionally bound to a particular + # svn revision via: "svn_revno=commit_sha1", filter them out here: + my @exec_parents; + foreach my $p (@parents) { + next unless defined $p; + if ($p =~ /^(\d+)=($sha1_short)$/o) { + if ($1 == $log_msg->{revision}) { + push @exec_parents, $2; + } + } else { + push @exec_parents, $p if $p =~ /$sha1_short/o; + } + } + + my $pid = fork; + defined $pid or croak $!; + if ($pid == 0) { + $ENV{GIT_INDEX_FILE} = $GIT_SVN_INDEX; + git_addremove(); + chomp(my $tree = `git-write-tree`); + croak if $?; + my $msg_fh = IO::File->new_tmpfile or croak $!; + print $msg_fh $log_msg->{msg}, "\ngit-svn-id: ", + "$SVN_URL\@$log_msg->{revision}", + " $uuid\n" or croak $!; + $msg_fh->flush == 0 or croak $!; + seek $msg_fh, 0, 0 or croak $!; + + $ENV{GIT_AUTHOR_NAME} = $ENV{GIT_COMMITTER_NAME} = + $log_msg->{author}; + $ENV{GIT_AUTHOR_EMAIL} = $ENV{GIT_COMMITTER_EMAIL} = + $log_msg->{author}."\@$uuid"; + $ENV{GIT_AUTHOR_DATE} = $ENV{GIT_COMMITTER_DATE} = + $log_msg->{date}; + my @exec = ('git-commit-tree',$tree); + push @exec, '-p', $_ foreach @exec_parents; + open STDIN, '<&', $msg_fh or croak $!; + open STDOUT, '>&', $out_fh or croak $!; + exec @exec or croak $!; + } + waitpid($pid,0); + croak if $?; + + $out_fh->flush == 0 or croak $!; + seek $out_fh, 0, 0 or croak $!; + chomp(my $commit = do { local $/; <$out_fh> }); + if ($commit !~ /^$sha1$/o) { + croak "Failed to commit, invalid sha1: $commit\n"; + } + my @update_ref = ('git-update-ref',"refs/heads/$GIT_SVN-HEAD",$commit); + if (my $primary_parent = shift @exec_parents) { + push @update_ref, $primary_parent; + } + sys(@update_ref); + sys('git-update-ref',"$GIT_SVN/revs/$log_msg->{revision}",$commit); + print "r$log_msg->{revision} = $commit\n"; + return $commit; +} + +sub blob_to_symlink { + my ($blob, $link) = @_; + defined $link or croak "\$link not defined!\n"; + croak "Not a sha1: $blob\n" unless $blob =~ /^$sha1$/o; + my $dest = `git-cat-file blob $blob`; # no newline, so no chomp + symlink $dest, $link or croak $!; +} + +sub blob_to_file { + my ($blob, $file) = @_; + defined $file or croak "\$file not defined!\n"; + croak "Not a sha1: $blob\n" unless $blob =~ /^$sha1$/o; + open my $blob_fh, '>', $file or croak "$!: $file\n"; + my $pid = fork; + defined $pid or croak $!; + + if ($pid == 0) { + open STDOUT, '>&', $blob_fh or croak $!; + exec('git-cat-file','blob',$blob); + } + waitpid $pid, 0; + croak $? if $?; + + close $blob_fh or croak $!; +} + +sub safe_qx { + my $pid = open my $child, '-|'; + defined $pid or croak $!; + if ($pid == 0) { + exec(@_) or croak $?; + } + my @ret = (<$child>); + close $child or croak $?; + die $? if $?; # just in case close didn't error out + return wantarray ? @ret : join('',@ret); +} + +sub svn_check_ignore_externals { + return if $_no_ignore_ext; + unless (grep /ignore-externals/,(safe_qx(qw(svn co -h)))) { + print STDERR "W: Installed svn version does not support ", + "--ignore-externals\n"; + $_no_ignore_ext = 1; + } +} +__END__ + +Data structures: + +@svn_log = array of log_msg hashes + +$log_msg hash +{ + msg => 'whitespace-formatted log entry +', # trailing newline is preserved + revision => '8', # integer + date => '2004-02-24T17:01:44.108345Z', # commit date + author => 'committer name' +}; + + +@mods = array of diff-index line hashes, each element represents one line + of diff-index output + +diff-index line ($m hash) +{ + mode_a => first column of diff-index output, no leading ':', + mode_b => second column of diff-index output, + sha1_b => sha1sum of the final blob, + chg => change type [MCRAD], + file_a => original file name of a file (iff chg is 'C' or 'R') + file_b => new/current file name of a file (any chg) +} +; diff --git a/contrib/git-svn/git-svn.txt b/contrib/git-svn/git-svn.txt new file mode 100644 index 0000000..4b79fb0 --- /dev/null +++ b/contrib/git-svn/git-svn.txt @@ -0,0 +1,208 @@ +git-svn(1) +========== + +NAME +---- +git-svn - bidirectional operation between a single Subversion branch and git + +SYNOPSIS +-------- +'git-svn' [options] [arguments] + +DESCRIPTION +----------- +git-svn is a simple conduit for changesets between a single Subversion +branch and git. + +git-svn is not to be confused with git-svnimport. The were designed +with very different goals in mind. + +git-svn is designed for an individual developer who wants a +bidirectional flow of changesets between a single branch in Subversion +and an arbitrary number of branches in git. git-svnimport is designed +for read-only operation on repositories that match a particular layout +(albeit the recommended one by SVN developers). + +For importing svn, git-svnimport is potentially more powerful when +operating on repositories organized under the recommended +trunk/branch/tags structure, and should be faster, too. + +git-svn completely ignores the very limited view of branching that +Subversion has. This allows git-svn to be much easier to use, +especially on repositories that are not organized in a manner that +git-svnimport is designed for. + +COMMANDS +-------- +init:: + Creates an empty git repository with additional metadata + directories for git-svn. The SVN_URL must be specified + at this point. + +fetch:: + Fetch unfetched revisions from the SVN_URL we are tracking. + refs/heads/git-svn-HEAD will be updated to the latest revision. + +commit:: + Commit specified commit or tree objects to SVN. This relies on + your imported fetch data being up-to-date. This makes + absolutely no attempts to do patching when committing to SVN, it + simply overwrites files with those specified in the tree or + commit. All merging is assumed to have taken place + independently of git-svn functions. + +rebuild:: + Not a part of daily usage, but this is a useful command if + you've just cloned a repository (using git-clone) that was + tracked with git-svn. Unfortunately, git-clone does not clone + git-svn metadata and the svn working tree that git-svn uses for + its operations. This rebuilds the metadata so git-svn can + resume fetch operations. SVN_URL may be optionally specified if + the directory/repository you're tracking has moved or changed + protocols. + +OPTIONS +------- +-r :: +--revision :: + Only used with the 'fetch' command. + + Takes any valid -r svn would accept and passes it + directly to svn. -r: ranges and "{" DATE "}" syntax + is also supported. This is passed directly to svn, see svn + documentation for more details. + + This can allow you to make partial mirrors when running fetch. + +-:: +--stdin:: + Only used with the 'commit' command. + + Read a list of commits from stdin and commit them in reverse + order. Only the leading sha1 is read from each line, so + git-rev-list --pretty=oneline output can be used. + +--rmdir:: + Only used with the 'commit' command. + + Remove directories from the SVN tree if there are no files left + behind. SVN can version empty directories, and they are not + removed by default if there are no files left in them. git + cannot version empty directories. Enabling this flag will make + the commit to SVN act like git. + +-e:: +--edit:: + Only used with the 'commit' command. + + Edit the commit message before committing to SVN. This is off by + default for objects that are commits, and forced on when committing + tree objects. + +COMPATIBILITY OPTIONS +--------------------- +--no-ignore-externals:: + Only used with the 'fetch' and 'rebuild' command. + + By default, git-svn passes --ignore-externals to svn to avoid + fetching svn:external trees into git. Pass this flag to enable + externals tracking directly via git. + + Versions of svn that do not support --ignore-externals are + automatically detected and this flag will be automatically + enabled for them. + + Otherwise, do not enable this flag unless you know what you're + doing. + +--no-stop-on-copy:: + Only used with the 'fetch' command. + + By default, git-svn passes --stop-on-copy to avoid dealing with + the copied/renamed branch directory problem entirely. A + copied/renamed branch is the result of a being created + in the past from a different source. These are problematic to + deal with even when working purely with svn if you work inside + subdirectories. + + Do not use this flag unless you know exactly what you're getting + yourself into. You have been warned. + +Examples +~~~~~~~~ + +Tracking and contributing to an Subversion managed-project: + +# Initialize a tree (like git init-db):: + git-svn init http://svn.foo.org/project/trunk +# Fetch remote revisions:: + git-svn fetch +# Create your own branch to hack on:: + git checkout -b my-branch git-svn-HEAD +# Commit only the git commits you want to SVN:: + git-svn commit [ ...] +# Commit all the git commits from my-branch that don't exist in SVN:: + git rev-list --pretty=oneline git-svn-HEAD..my-branch | git-svn commit +# Something is committed to SVN, pull the latest into your branch:: + git-svn fetch && git pull . git-svn-HEAD + +DESIGN PHILOSOPHY +----------------- +Merge tracking in Subversion is lacking and doing branched development +with Subversion is cumbersome as a result. git-svn completely forgoes +any automated merge/branch tracking on the Subversion side and leaves it +entirely up to the user on the git side. It's simply not worth it to do +a useful translation when the the original signal is weak. + +TRACKING MULTIPLE REPOSITORIES OR BRANCHES +------------------------------------------ +This is for advanced users, most users should ignore this section. + +Because git-svn does not care about relationships between different +branches or directories in a Subversion repository, git-svn has a simple +hack to allow it to track an arbitrary number of related _or_ unrelated +SVN repositories via one git repository. Simply set the GIT_SVN_ID +environment variable to a name other other than "git-svn" (the default) +and git-svn will ignore the contents of the $GIT_DIR/git-svn directory +and instead do all of its work in $GIT_DIR/$GIT_SVN_ID for that +invocation. + +ADDITIONAL FETCH ARGUMENTS +-------------------------- +This is for advanced users, most users should ignore this section. + +Unfetched SVN revisions may be imported as children of existing commits +by specifying additional arguments to 'fetch'. Additional parents may +optionally be specified in the form of sha1 hex sums at the +command-line. Unfetched SVN revisions may also be tied to particular +git commits with the following syntax: + + svn_revision_number=git_commit_sha1 + +This allows you to tie unfetched SVN revision 375 to your current HEAD:: + + git-svn fetch 375=$(git-rev-parse HEAD) + +BUGS +---- +If somebody commits a conflicting changeset to SVN at a bad moment +(right before you commit) causing a conflict and your commit to fail, +your svn working tree ($GIT_DIR/git-svn/tree) may be dirtied. The +easiest thing to do is probably just to rm -rf $GIT_DIR/git-svn/tree and +run 'rebuild'. + +We ignore all SVN properties except svn:executable. Too difficult to +map them since we rely heavily on git write-tree being _exactly_ the +same on both the SVN and git working trees and I prefer not to clutter +working trees with metadata files. + +svn:keywords can't be ignored in Subversion (at least I don't know of +a way to ignore them). + +Author +------ +Written by Eric Wong . + +Documentation +------------- +Written by Eric Wong . -- cgit v0.10.2-6-g49f6