]> git.vanrenterghem.biz Git - git.ikiwiki.info.git/blobdiff - IkiWiki/Plugin/git.pm
add news item for ikiwiki 3.20140102
[git.ikiwiki.info.git] / IkiWiki / Plugin / git.pm
index 3a8476e7d24444531f733b6b2b2ae64ce7d8105b..77c0678bcbd8dfd32c13b164477ea899d0c9f38a 100644 (file)
@@ -5,15 +5,16 @@ use warnings;
 use strict;
 use IkiWiki;
 use Encode;
+use URI::Escape q{uri_escape_utf8};
 use open qw{:utf8 :std};
 
 my $sha1_pattern     = qr/[0-9a-fA-F]{40}/; # pattern to validate Git sha1sums
 my $dummy_commit_msg = 'dummy commit';      # message to skip in recent changes
-my $no_chdir=0;
 
-sub import { #{{{
+sub import {
        hook(type => "checkconfig", id => "git", call => \&checkconfig);
        hook(type => "getsetup", id => "git", call => \&getsetup);
+       hook(type => "genwrapper", id => "git", call => \&genwrapper);
        hook(type => "rcs", id => "rcs_update", call => \&rcs_update);
        hook(type => "rcs", id => "rcs_prepedit", call => \&rcs_prepedit);
        hook(type => "rcs", id => "rcs_commit", call => \&rcs_commit);
@@ -24,10 +25,15 @@ sub import { #{{{
        hook(type => "rcs", id => "rcs_recentchanges", call => \&rcs_recentchanges);
        hook(type => "rcs", id => "rcs_diff", call => \&rcs_diff);
        hook(type => "rcs", id => "rcs_getctime", call => \&rcs_getctime);
+       hook(type => "rcs", id => "rcs_getmtime", call => \&rcs_getmtime);
        hook(type => "rcs", id => "rcs_receive", call => \&rcs_receive);
-} #}}}
+       hook(type => "rcs", id => "rcs_preprevert", call => \&rcs_preprevert);
+       hook(type => "rcs", id => "rcs_revert", call => \&rcs_revert);
+       hook(type => "rcs", id => "rcs_find_changes", call => \&rcs_find_changes);
+       hook(type => "rcs", id => "rcs_get_current_rev", call => \&rcs_get_current_rev);
+}
 
-sub checkconfig () { #{{{
+sub checkconfig () {
        if (! defined $config{gitorigin_branch}) {
                $config{gitorigin_branch}="origin";
        }
@@ -39,23 +45,38 @@ sub checkconfig () { #{{{
                push @{$config{wrappers}}, {
                        wrapper => $config{git_wrapper},
                        wrappermode => (defined $config{git_wrappermode} ? $config{git_wrappermode} : "06755"),
+                       wrapper_background_command => $config{git_wrapper_background_command},
                };
        }
+
        if (defined $config{git_test_receive_wrapper} &&
-           length $config{git_test_receive_wrapper}) {
+           length $config{git_test_receive_wrapper} &&
+           defined $config{untrusted_committers} &&
+           @{$config{untrusted_committers}}) {
                push @{$config{wrappers}}, {
                        test_receive => 1,
                        wrapper => $config{git_test_receive_wrapper},
-                       wrappermode => "0755",
+                       wrappermode => (defined $config{git_wrappermode} ? $config{git_wrappermode} : "06755"),
                };
        }
-} #}}}
 
-sub getsetup () { #{{{
+       # Avoid notes, parser does not handle and they only slow things down.
+       $ENV{GIT_NOTES_REF}="";
+       
+       # Run receive test only if being called by the wrapper, and not
+       # when generating same.
+       if ($config{test_receive} && ! exists $config{wrapper}) {
+               require IkiWiki::Receive;
+               IkiWiki::Receive::test();
+       }
+}
+
+sub getsetup () {
        return
                plugin => {
                        safe => 0, # rcs plugin
                        rebuild => undef,
+                       section => "rcs",
                },
                git_wrapper => {
                        type => "string",
@@ -64,6 +85,13 @@ sub getsetup () { #{{{
                        safe => 0, # file
                        rebuild => 0,
                },
+               git_wrapper_background_command => {
+                       type => "string",
+                       example => "git push github",
+                       description => "shell command for git_wrapper to run, in the background",
+                       safe => 0, # command
+                       rebuild => 0,
+               },
                git_wrappermode => {
                        type => "string",
                        example => '06755',
@@ -87,15 +115,15 @@ sub getsetup () { #{{{
                },
                historyurl => {
                        type => "string",
-                       example => "http://git.example.com/gitweb.cgi?p=wiki.git;a=history;f=[[file]]",
+                       example => "http://git.example.com/gitweb.cgi?p=wiki.git;a=history;f=[[file]];hb=HEAD",
                        description => "gitweb url to show file history ([[file]] substituted)",
                        safe => 1,
                        rebuild => 1,
                },
                diffurl => {
                        type => "string",
-                       example => "http://git.example.com/gitweb.cgi?p=wiki.git;a=blobdiff;h=[[sha1_to]];hp=[[sha1_from]];hb=[[sha1_parent]];f=[[file]]",
-                       description => "gitweb url to show a diff ([[sha1_to]], [[sha1_from]], [[sha1_parent]], and [[file]] substituted)",
+                       example => "http://git.example.com/gitweb.cgi?p=wiki.git;a=blobdiff;f=[[file]];h=[[sha1_to]];hp=[[sha1_from]];hb=[[sha1_commit]];hpb=[[sha1_parent]]",
+                       description => "gitweb url to show a diff ([[file]], [[sha1_to]], [[sha1_from]], [[sha1_commit]], and [[sha1_parent]] substituted)",
                        safe => 1,
                        rebuild => 1,
                },
@@ -113,13 +141,35 @@ sub getsetup () { #{{{
                        safe => 0, # paranoia
                        rebuild => 0,
                },
-} #}}}
+}
 
-sub safe_git (&@) { #{{{
-       # Start a child process safely without resorting /bin/sh.
-       # Return command output or success state (in scalar context).
+sub genwrapper {
+       if ($config{test_receive}) {
+               require IkiWiki::Receive;
+               return IkiWiki::Receive::genwrapper();
+       }
+       else {
+               return "";
+       }
+}
+
+my $git_dir=undef;
+my $prefix=undef;
 
-       my ($error_handler, @cmdline) = @_;
+sub in_git_dir ($$) {
+       $git_dir=shift;
+       my @ret=shift->();
+       $git_dir=undef;
+       $prefix=undef;
+       return @ret;
+}
+
+sub safe_git (&@) {
+       # Start a child process safely without resorting to /bin/sh.
+       # Returns command output (in list content) or success state
+       # (in scalar context), or runs the specified data handler.
+
+       my ($error_handler, $data_handler, @cmdline) = @_;
 
        my $pid = open my $OUT, "-|";
 
@@ -128,18 +178,35 @@ sub safe_git (&@) { #{{{
        if (!$pid) {
                # In child.
                # Git commands want to be in wc.
-               if (! $no_chdir) {
+               if (! defined $git_dir) {
                        chdir $config{srcdir}
-                           or error("Cannot chdir to $config{srcdir}: $!");
+                           or error("cannot chdir to $config{srcdir}: $!");
+               }
+               else {
+                       chdir $git_dir
+                           or error("cannot chdir to $git_dir: $!");
                }
                exec @cmdline or error("Cannot exec '@cmdline': $!");
        }
        # In parent.
 
+       # git output is probably utf-8 encoded, but may contain
+       # other encodings or invalidly encoded stuff. So do not rely
+       # on the normal utf-8 IO layer, decode it by hand.
+       binmode($OUT);
+
        my @lines;
        while (<$OUT>) {
+               $_=decode_utf8($_, 0);
+
                chomp;
-               push @lines, $_;
+
+               if (! defined $data_handler) {
+                       push @lines, $_;
+               }
+               else {
+                       last unless $data_handler->($_);
+               }
        }
 
        close $OUT;
@@ -149,12 +216,12 @@ sub safe_git (&@) { #{{{
        return wantarray ? @lines : ($? == 0);
 }
 # Convenient wrappers.
-sub run_or_die ($@) { safe_git(\&error, @_) }
-sub run_or_cry ($@) { safe_git(sub { warn @_ },  @_) }
-sub run_or_non ($@) { safe_git(undef,            @_) }
-#}}}
+sub run_or_die ($@) { safe_git(\&error, undef, @_) }
+sub run_or_cry ($@) { safe_git(sub { warn @_ }, undef, @_) }
+sub run_or_non ($@) { safe_git(undef, undef, @_) }
 
-sub merge_past ($$$) { #{{{
+
+sub merge_past ($$$) {
        # Unlike with Subversion, Git cannot make a 'svn merge -rN:M file'.
        # Git merge commands work with the committed changes, except in the
        # implicit case of '-m' of git checkout(1).  So we should invent a
@@ -246,17 +313,38 @@ sub merge_past ($$$) { #{{{
        error("Git merge failed!\n$failure\n") if $failure;
 
        return $conflict;
-} #}}}
+}
 
-sub parse_diff_tree ($@) { #{{{
+sub decode_git_file ($) {
+       my $file=shift;
+
+       # git does not output utf-8 filenames, but instead
+       # double-quotes them with the utf-8 characters
+       # escaped as \nnn\nnn.
+       if ($file =~ m/^"(.*)"$/) {
+               ($file=$1) =~ s/\\([0-7]{1,3})/chr(oct($1))/eg;
+       }
+
+       # strip prefix if in a subdir
+       if (! defined $prefix) {
+               ($prefix) = run_or_die('git', 'rev-parse', '--show-prefix');
+               if (! defined $prefix) {
+                       $prefix="";
+               }
+       }
+       $file =~ s/^\Q$prefix\E//;
+
+       return decode("utf8", $file);
+}
+
+sub parse_diff_tree ($) {
        # Parse the raw diff tree chunk and return the info hash.
        # See git-diff-tree(1) for the syntax.
-
-       my ($prefix, $dt_ref) = @_;
+       my $dt_ref = shift;
 
        # End of stream?
-       return if !defined @{ $dt_ref } ||
-                 !defined @{ $dt_ref }[0] || !length @{ $dt_ref }[0];
+       return if ! @{ $dt_ref } ||
+                 !defined $dt_ref->[0] || !length $dt_ref->[0];
 
        my %ci;
        # Header line.
@@ -286,8 +374,9 @@ sub parse_diff_tree ($@) { #{{{
                        $ci{ "${who}_epoch" } = $epoch;
                        $ci{ "${who}_tz"    } = $tz;
 
-                       if ($name =~ m/^[^<]+\s+<([^@>]+)/) {
-                               $ci{"${who}_username"} = $1;
+                       if ($name =~ m/^([^<]+)\s+<([^@>]+)/) {
+                               $ci{"${who}_name"} = $1;
+                               $ci{"${who}_username"} = $2;
                        }
                        elsif ($name =~ m/^([^<]+)\s+<>$/) {
                                $ci{"${who}_username"} = $1;
@@ -335,16 +424,9 @@ sub parse_diff_tree ($@) { #{{{
                        my $sha1_to = shift(@tmp);
                        my $status = shift(@tmp);
 
-                       # git does not output utf-8 filenames, but instead
-                       # double-quotes them with the utf-8 characters
-                       # escaped as \nnn\nnn.
-                       if ($file =~ m/^"(.*)"$/) {
-                               ($file=$1) =~ s/\\([0-7]{1,3})/chr(oct($1))/eg;
-                       }
-                       $file =~ s/^\Q$prefix\E//;
                        if (length $file) {
                                push @{ $ci{'details'} }, {
-                                       'file'      => decode("utf8", $file),
+                                       'file'      => decode_git_file($file),
                                        'sha1_from' => $sha1_from[0],
                                        'sha1_to'   => $sha1_to,
                                        'mode_from' => $mode_from[0],
@@ -358,9 +440,9 @@ sub parse_diff_tree ($@) { #{{{
        }
 
        return \%ci;
-} #}}}
+}
 
-sub git_commit_info ($;$) { #{{{
+sub git_commit_info ($;$) {
        # Return an array of commit info hashes of num commits
        # starting from the given sha1sum.
        my ($sha1, $num) = @_;
@@ -371,98 +453,161 @@ sub git_commit_info ($;$) { #{{{
        my @raw_lines = run_or_die('git', 'log', @opts,
                '--pretty=raw', '--raw', '--abbrev=40', '--always', '-c',
                '-r', $sha1, '--', '.');
-       my ($prefix) = run_or_die('git', 'rev-parse', '--show-prefix');
 
        my @ci;
-       while (my $parsed = parse_diff_tree(($prefix or ""), \@raw_lines)) {
+       while (my $parsed = parse_diff_tree(\@raw_lines)) {
                push @ci, $parsed;
        }
 
        warn "Cannot parse commit info for '$sha1' commit" if !@ci;
 
        return wantarray ? @ci : $ci[0];
-} #}}}
+}
 
-sub git_sha1 (;$) { #{{{
-       # Return head sha1sum (of given file).
-       my $file = shift || q{--};
+sub rcs_find_changes ($) {
+       my $oldrev=shift;
 
+       my @raw_lines = run_or_die('git', 'log',
+               '--pretty=raw', '--raw', '--abbrev=40', '--always', '-c',
+               '--no-renames', , '--reverse',
+               '-r', "$oldrev..HEAD", '--', '.');
+
+       # Due to --reverse, we see changes in chronological order.
+       my %changed;
+       my %deleted;
+       my $nullsha = 0 x 40;
+       my $newrev=$oldrev;
+       while (my $ci = parse_diff_tree(\@raw_lines)) {
+               $newrev=$ci->{sha1};
+               foreach my $i (@{$ci->{details}}) {
+                       my $file=$i->{file};
+                       if ($i->{sha1_to} eq $nullsha) {
+                               delete $changed{$file};
+                               $deleted{$file}=1;
+                       }
+                       else {
+                               delete $deleted{$file};
+                               $changed{$file}=1;
+                       }
+               }
+       }
+
+       return (\%changed, \%deleted, $newrev);
+}
+
+sub git_sha1_file ($) {
+       my $file=shift;
+       git_sha1("--", $file);
+}
+
+sub git_sha1 (@) {
        # Ignore error since a non-existing file might be given.
        my ($sha1) = run_or_non('git', 'rev-list', '--max-count=1', 'HEAD',
-               '--', $file);
-       if ($sha1) {
+               '--', @_);
+       if (defined $sha1) {
                ($sha1) = $sha1 =~ m/($sha1_pattern)/; # sha1 is untainted now
-       } else { debug("Empty sha1sum for '$file'.") }
-       return defined $sha1 ? $sha1 : q{};
-} #}}}
+       }
+       return defined $sha1 ? $sha1 : '';
+}
+
+sub rcs_get_current_rev () {
+       git_sha1();
+}
 
-sub rcs_update () { #{{{
+sub rcs_update () {
        # Update working directory.
 
        if (length $config{gitorigin_branch}) {
-               run_or_cry('git', 'pull', $config{gitorigin_branch});
+               run_or_cry('git', 'pull', '--prune', $config{gitorigin_branch});
        }
-} #}}}
+}
 
-sub rcs_prepedit ($) { #{{{
+sub rcs_prepedit ($) {
        # Return the commit sha1sum of the file when editing begins.
        # This will be later used in rcs_commit if a merge is required.
        my ($file) = @_;
 
-       return git_sha1($file);
-} #}}}
+       return git_sha1_file($file);
+}
 
-sub rcs_commit ($$$;$$) { #{{{
+sub rcs_commit (@) {
        # Try to commit the page; returns undef on _success_ and
        # a version of the page with the rcs's conflict markers on
        # failure.
-
-       my ($file, $message, $rcstoken, $user, $ipaddr) = @_;
+       my %params=@_;
 
        # Check to see if the page has been changed by someone else since
        # rcs_prepedit was called.
-       my $cur    = git_sha1($file);
-       my ($prev) = $rcstoken =~ /^($sha1_pattern)$/; # untaint
+       my $cur    = git_sha1_file($params{file});
+       my ($prev) = $params{token} =~ /^($sha1_pattern)$/; # untaint
 
        if (defined $cur && defined $prev && $cur ne $prev) {
-               my $conflict = merge_past($prev, $file, $dummy_commit_msg);
+               my $conflict = merge_past($prev, $params{file}, $dummy_commit_msg);
                return $conflict if defined $conflict;
        }
 
-       rcs_add($file); 
-       return rcs_commit_staged($message, $user, $ipaddr);
-} #}}}
+       return rcs_commit_helper(@_);
+}
 
-sub rcs_commit_staged ($$$) {
+sub rcs_commit_staged (@) {
        # Commits all staged changes. Changes can be staged using rcs_add,
        # rcs_remove, and rcs_rename.
-       my ($message, $user, $ipaddr)=@_;
+       return rcs_commit_helper(@_);
+}
 
-       # Set the commit author and email to the web committer.
+sub rcs_commit_helper (@) {
+       my %params=@_;
+       
        my %env=%ENV;
-       if (defined $user || defined $ipaddr) {
-               my $u=defined $user ? $user : $ipaddr;
-               $ENV{GIT_AUTHOR_NAME}=$u;
-               $ENV{GIT_AUTHOR_EMAIL}="$u\@web";
+
+       if (defined $params{session}) {
+               # Set the commit author and email based on web session info.
+               my $u;
+               if (defined $params{session}->param("name")) {
+                       $u=$params{session}->param("name");
+               }
+               elsif (defined $params{session}->remote_addr()) {
+                       $u=$params{session}->remote_addr();
+               }
+               if (defined $u) {
+                       $u=encode_utf8($u);
+                       $ENV{GIT_AUTHOR_NAME}=$u;
+               }
+               if (defined $params{session}->param("nickname")) {
+                       $u=encode_utf8($params{session}->param("nickname"));
+                       $u=~s/\s+/_/g;
+                       $u=~s/[^-_0-9[:alnum:]]+//g;
+               }
+               if (defined $u) {
+                       $ENV{GIT_AUTHOR_EMAIL}="$u\@web";
+               }
        }
 
-       $message = IkiWiki::possibly_foolish_untaint($message);
+       $params{message} = IkiWiki::possibly_foolish_untaint($params{message});
        my @opts;
-       if ($message !~ /\S/) {
+       if ($params{message} !~ /\S/) {
                # Force git to allow empty commit messages.
                # (If this version of git supports it.)
                my ($version)=`git --version` =~ /git version (.*)/;
-               if ($version ge "1.5.4") {
+               if ($version ge "1.7.8") {
+                       push @opts, "--allow-empty-message", "--no-edit";
+               }
+               if ($version ge "1.7.2") {
+                       push @opts, "--allow-empty-message";
+               }
+               elsif ($version ge "1.5.4") {
                        push @opts, '--cleanup=verbatim';
                }
                else {
-                       $message.=".";
+                       $params{message}.=".";
                }
        }
-       push @opts, '-q';
-       # git commit returns non-zero if file has not been really changed.
-       # so we should ignore its exit status (hence run_or_non).
-       if (run_or_non('git', 'commit', @opts, '-m', $message)) {
+       if (exists $params{file}) {
+               push @opts, '--', $params{file};
+       }
+       # git commit returns non-zero if nothing really changed.
+       # So we should ignore its exit status (hence run_or_non).
+       if (run_or_non('git', 'commit', '-m', $params{message}, '-q', @opts)) {
                if (length $config{gitorigin_branch}) {
                        run_or_cry('git', 'push', $config{gitorigin_branch});
                }
@@ -472,29 +617,29 @@ sub rcs_commit_staged ($$$) {
        return undef; # success
 }
 
-sub rcs_add ($) { # {{{
+sub rcs_add ($) {
        # Add file to archive.
 
        my ($file) = @_;
 
        run_or_cry('git', 'add', $file);
-} #}}}
+}
 
-sub rcs_remove ($) { # {{{
+sub rcs_remove ($) {
        # Remove file from archive.
 
        my ($file) = @_;
 
        run_or_cry('git', 'rm', '-f', $file);
-} #}}}
+}
 
-sub rcs_rename ($$) { # {{{
+sub rcs_rename ($$) {
        my ($src, $dest) = @_;
 
        run_or_cry('git', 'mv', '-f', $src, $dest);
-} #}}}
+}
 
-sub rcs_recentchanges ($) { #{{{
+sub rcs_recentchanges ($) {
        # List of recent changes.
 
        my ($num) = @_;
@@ -515,12 +660,14 @@ sub rcs_recentchanges ($) { #{{{
                my @pages;
                foreach my $detail (@{ $ci->{'details'} }) {
                        my $file = $detail->{'file'};
+                       my $efile = uri_escape_utf8($file);
 
                        my $diffurl = defined $config{'diffurl'} ? $config{'diffurl'} : "";
-                       $diffurl =~ s/\[\[file\]\]/$file/go;
+                       $diffurl =~ s/\[\[file\]\]/$efile/go;
                        $diffurl =~ s/\[\[sha1_parent\]\]/$ci->{'parent'}/go;
                        $diffurl =~ s/\[\[sha1_from\]\]/$detail->{'sha1_from'}/go;
                        $diffurl =~ s/\[\[sha1_to\]\]/$detail->{'sha1_to'}/go;
+                       $diffurl =~ s/\[\[sha1_commit\]\]/$sha1/go;
 
                        push @pages, {
                                page => pagename($file),
@@ -538,7 +685,16 @@ sub rcs_recentchanges ($) { #{{{
 
                my $user=$ci->{'author_username'};
                my $web_commit = ($ci->{'author'} =~ /\@web>/);
-               
+               my $nickname;
+
+               # Set nickname only if a non-url author_username is available,
+               # and author_name is an url.
+               if ($user !~ /:\/\// && defined $ci->{'author_name'} &&
+                   $ci->{'author_name'} =~ /:\/\//) {
+                       $nickname=$user;
+                       $user=$ci->{'author_name'};
+               }
+
                # compatability code for old web commit messages
                if (! $web_commit &&
                      defined $messages[0] &&
@@ -551,6 +707,7 @@ sub rcs_recentchanges ($) { #{{{
                push @rets, {
                        rev        => $sha1,
                        user       => $user,
+                       nickname   => $nickname,
                        committype => $web_commit ? "web" : "git",
                        when       => $when,
                        message    => [@messages],
@@ -561,42 +718,84 @@ sub rcs_recentchanges ($) { #{{{
        }
 
        return @rets;
-} #}}}
+}
 
-sub rcs_diff ($) { #{{{
+sub rcs_diff ($;$) {
        my $rev=shift;
+       my $maxlines=shift;
        my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
        my @lines;
-       foreach my $line (run_or_non("git", "show", $sha1)) {
-               if (@lines || $line=~/^diff --git/) {
-                       push @lines, $line."\n";
-               }
-       }
+       my $addlines=sub {
+               my $line=shift;
+               return if defined $maxlines && @lines == $maxlines;
+               push @lines, $line."\n"
+                       if (@lines || $line=~/^diff --git/);
+               return 1;
+       };
+       safe_git(undef, $addlines, "git", "show", $sha1);
        if (wantarray) {
                return @lines;
        }
        else {
                return join("", @lines);
        }
-} #}}}
+}
+
+{
+my %time_cache;
 
-sub rcs_getctime ($) { #{{{
+sub findtimes ($$) {
        my $file=shift;
-       # Remove srcdir prefix
-       $file =~ s/^\Q$config{srcdir}\E\/?//;
+       my $id=shift; # 0 = mtime ; 1 = ctime
+
+       if (! keys %time_cache) {
+               my $date;
+               foreach my $line (run_or_die('git', 'log',
+                               '--pretty=format:%at',
+                               '--name-only', '--relative')) {
+                       if (! defined $date && $line =~ /^(\d+)$/) {
+                               $date=$line;
+                       }
+                       elsif (! length $line) {
+                               $date=undef;
+                       }
+                       else {
+                               my $f=decode_git_file($line);
 
-       my $sha1  = git_sha1($file);
-       my $ci    = git_commit_info($sha1, 1);
-       my $ctime = $ci->{'author_epoch'};
-       debug("ctime for '$file': ". localtime($ctime));
+                               if (! $time_cache{$f}) {
+                                       $time_cache{$f}[0]=$date; # mtime
+                               }
+                               $time_cache{$f}[1]=$date; # ctime
+                       }
+               }
+       }
 
-       return $ctime;
-} #}}}
+       return exists $time_cache{$file} ? $time_cache{$file}[$id] : 0;
+}
 
-sub rcs_receive () { #{{{
+}
+
+sub rcs_getctime ($) {
+       my $file=shift;
+
+       return findtimes($file, 1);
+}
+
+sub rcs_getmtime ($) {
+       my $file=shift;
+
+       return findtimes($file, 0);
+}
+
+{
+my $ret;
+sub git_find_root {
        # The wiki may not be the only thing in the git repo.
        # Determine if it is in a subdirectory by examining the srcdir,
        # and its parents, looking for the .git directory.
+
+       return @$ret if defined $ret;
+       
        my $subdir="";
        my $dir=$config{srcdir};
        while (! -d "$dir/.git") {
@@ -607,80 +806,140 @@ sub rcs_receive () { #{{{
                }
        }
 
+       $ret=[$subdir, $dir];
+       return @$ret;
+}
+
+}
+
+sub git_parse_changes {
+       my $reverted = shift;
+       my @changes = @_;
+
+       my ($subdir, $rootdir) = git_find_root();
+       my @rets;
+       foreach my $ci (@changes) {
+               foreach my $detail (@{ $ci->{'details'} }) {
+                       my $file = $detail->{'file'};
+
+                       # check that all changed files are in the subdir
+                       if (length $subdir &&
+                           ! ($file =~ s/^\Q$subdir\E//)) {
+                               error sprintf(gettext("you are not allowed to change %s"), $file);
+                       }
+
+                       my ($action, $mode, $path);
+                       if ($detail->{'status'} =~ /^[M]+\d*$/) {
+                               $action="change";
+                               $mode=$detail->{'mode_to'};
+                       }
+                       elsif ($detail->{'status'} =~ /^[AM]+\d*$/) {
+                               $action= $reverted ? "remove" : "add";
+                               $mode=$detail->{'mode_to'};
+                       }
+                       elsif ($detail->{'status'} =~ /^[DAM]+\d*/) {
+                               $action= $reverted ? "add" : "remove";
+                               $mode=$detail->{'mode_from'};
+                       }
+                       else {
+                               error "unknown status ".$detail->{'status'};
+                       }
+
+                       # test that the file mode is ok
+                       if ($mode !~ /^100[64][64][64]$/) {
+                               error sprintf(gettext("you cannot act on a file with mode %s"), $mode);
+                       }
+                       if ($action eq "change") {
+                               if ($detail->{'mode_from'} ne $detail->{'mode_to'}) {
+                                       error gettext("you are not allowed to change file modes");
+                               }
+                       }
+
+                       # extract attachment to temp file
+                       if (($action eq 'add' || $action eq 'change') &&
+                           ! pagetype($file)) {
+                               eval q{use File::Temp};
+                               die $@ if $@;
+                               my $fh;
+                               ($fh, $path)=File::Temp::tempfile(undef, UNLINK => 1);
+                               my $cmd = "cd $git_dir && ".
+                                         "git show $detail->{sha1_to} > '$path'";
+                               if (system($cmd) != 0) {
+                                       error("failed writing temp file '$path'.");
+                               }
+                       }
+
+                       push @rets, {
+                               file => $file,
+                               action => $action,
+                               path => $path,
+                       };
+               }
+       }
+
+       return @rets;
+}
+
+sub rcs_receive () {
        my @rets;
        while (<>) {
                chomp;
                my ($oldrev, $newrev, $refname) = split(' ', $_, 3);
-               
+
                # only allow changes to gitmaster_branch
                if ($refname !~ /^refs\/heads\/\Q$config{gitmaster_branch}\E$/) {
                        error sprintf(gettext("you are not allowed to change %s"), $refname);
                }
-               
+
                # Avoid chdir when running git here, because the changes
                # are in the master git repo, not the srcdir repo.
+               # (Also, if a subdir is involved, we don't want to chdir to
+               # it and only see changes in it.)
                # The pre-receive hook already puts us in the right place.
-               $no_chdir=1;
-               my @changes=git_commit_info($oldrev."..".$newrev);
-               $no_chdir=0;
-
-               foreach my $ci (@changes) {
-                       foreach my $detail (@{ $ci->{'details'} }) {
-                               my $file = $detail->{'file'};
-
-                               # check that all changed files are in the
-                               # subdir
-                               if (length $subdir &&
-                                   ! ($file =~ s/^\Q$subdir\E//)) {
-                                       error sprintf(gettext("you are not allowed to change %s"), $file);
-                               }
+               in_git_dir(".", sub {
+                       push @rets, git_parse_changes(0, git_commit_info($oldrev."..".$newrev));
+               });
+       }
 
-                               my ($action, $mode, $path);
-                               if ($detail->{'status'} =~ /^[M]+\d*$/) {
-                                       $action="change";
-                                       $mode=$detail->{'mode_to'};
-                               }
-                               elsif ($detail->{'status'} =~ /^[AM]+\d*$/) {
-                                       $action="add";
-                                       $mode=$detail->{'mode_to'};
-                                       if (! pagetype($file)) {
-                                               eval q{use File::Temp};
-                                               die $@ if $@;
-                                               my $fh;
-                                               ($fh, $path)=File::Temp::tempfile("XXXXXXXXXX", UNLINK => 1);
-                                               if (system("git show ".$detail->{sha1_to}." > '$path'") != 0) {
-                                                       error("failed writing temp file");
-                                               }
-                                       }
-                               }
-                               elsif ($detail->{'status'} =~ /^[DAM]+\d*/) {
-                                       $action="remove";
-                                       $mode=$detail->{'mode_from'};
-                               }
-                               else {
-                                       error "unknown status ".$detail->{'status'};
-                               }
-                               
-                               # test that the file mode is ok
-                               if ($mode !~ /^100[64][64][64]$/) {
-                                       error sprintf(gettext("you cannot act on a file with mode %s"), $mode);
-                               }
-                               if ($action eq "change") {
-                                       if ($detail->{'mode_from'} ne $detail->{'mode_to'}) {
-                                               error gettext("you are not allowed to change file modes");
-                                       }
-                               }
+       return reverse @rets;
+}
 
-                               push @rets, {
-                                       file => $file,
-                                       action => $action,
-                                       path => $path,
-                               };
-                       }
+sub rcs_preprevert ($) {
+       my $rev=shift;
+       my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+       # Examine changes from root of git repo, not from any subdir,
+       # in order to see all changes.
+       my ($subdir, $rootdir) = git_find_root();
+       in_git_dir($rootdir, sub {
+               my @commits=git_commit_info($sha1, 1);
+       
+               if (! @commits) {
+                       error "unknown commit"; # just in case
                }
-       }
 
-       return reverse @rets;
-} #}}}
+               # git revert will fail on merge commits. Add a nice message.
+               if (exists $commits[0]->{parents} &&
+                   @{$commits[0]->{parents}} > 1) {
+                       error gettext("you are not allowed to revert a merge");
+               }
+
+               git_parse_changes(1, @commits);
+       });
+}
+
+sub rcs_revert ($) {
+       # Try to revert the given rev; returns undef on _success_.
+       my $rev = shift;
+       my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+       if (run_or_non('git', 'revert', '--no-commit', $sha1)) {
+               return undef;
+       }
+       else {
+               run_or_die('git', 'reset', '--hard');
+               return sprintf(gettext("Failed to revert commit %s"), $sha1);
+       }
+}
 
 1