]> git.vanrenterghem.biz Git - git.ikiwiki.info.git/blobdiff - IkiWiki/Plugin/git.pm
t/git-cgi.t: fix race condition
[git.ikiwiki.info.git] / IkiWiki / Plugin / git.pm
index 6a7f6c3ae3f9eaf3e5dafab166fa3060d946cdf0..7a6a554952079787f8d5c15b4c4f74159812d1c9 100644 (file)
@@ -5,15 +5,17 @@ use warnings;
 use strict;
 use IkiWiki;
 use Encode;
 use strict;
 use IkiWiki;
 use Encode;
+use File::Path qw{remove_tree};
+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
 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 {
        hook(type => "checkconfig", id => "git", call => \&checkconfig);
        hook(type => "getsetup", id => "git", call => \&getsetup);
 
 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);
        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);
@@ -24,7 +26,12 @@ 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_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_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 () {
@@ -39,16 +46,30 @@ sub checkconfig () {
                push @{$config{wrappers}}, {
                        wrapper => $config{git_wrapper},
                        wrappermode => (defined $config{git_wrappermode} ? $config{git_wrappermode} : "06755"),
                push @{$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} &&
        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 => (defined $config{git_wrappermode} ? $config{git_wrappermode} : "06755"),
                };
        }
                push @{$config{wrappers}}, {
                        test_receive => 1,
                        wrapper => $config{git_test_receive_wrapper},
                        wrappermode => (defined $config{git_wrappermode} ? $config{git_wrappermode} : "06755"),
                };
        }
+
+       # 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 () {
 }
 
 sub getsetup () {
@@ -56,6 +77,7 @@ sub getsetup () {
                plugin => {
                        safe => 0, # rcs plugin
                        rebuild => undef,
                plugin => {
                        safe => 0, # rcs plugin
                        rebuild => undef,
+                       section => "rcs",
                },
                git_wrapper => {
                        type => "string",
                },
                git_wrapper => {
                        type => "string",
@@ -64,6 +86,13 @@ sub getsetup () {
                        safe => 0, # file
                        rebuild => 0,
                },
                        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',
                git_wrappermode => {
                        type => "string",
                        example => '06755',
@@ -87,15 +116,15 @@ sub getsetup () {
                },
                historyurl => {
                        type => "string",
                },
                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",
                        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]], [[sha1_commit]] 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,
                },
                        safe => 1,
                        rebuild => 1,
                },
@@ -115,11 +144,67 @@ sub getsetup () {
                },
 }
 
                },
 }
 
-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_stack;
+my $prefix;
+
+sub in_git_dir ($$) {
+       unshift @git_dir_stack, shift;
+       my @ret=shift->();
+       shift @git_dir_stack;
+       $prefix=undef;
+       return @ret;
+}
+
+# Loosely based on git-new-workdir from git contrib.
+sub create_temp_working_dir ($$) {
+       my $rootdir = shift;
+       my $branch = shift;
+       my $working = "$rootdir/.git/ikiwiki-temp-working";
+       remove_tree($working);
 
 
-       my ($error_handler, @cmdline) = @_;
+       foreach my $dir ("", ".git") {
+               if (!mkdir("$working/$dir")) {
+                       error("Unable to create $working/$dir: $!");
+               }
+       }
+
+       # Hooks are deliberately not included: we will commit to the temporary
+       # branch that is used in the temporary working tree, and we don't want
+       # to run the post-commit hook there.
+       #
+       # logs/refs is not included because we don't use the reflog.
+       # remotes, rr-cache, svn are similarly excluded.
+       foreach my $link ("config", "refs", "objects", "info", "packed-refs") {
+               if (!symlink("../../$link", "$working/.git/$link")) {
+                       error("Unable to create symlink $working/.git/$link: $!");
+               }
+       }
+
+       open (my $out, '>', "$working/.git/HEAD") or
+               error("failed to write $working.git/HEAD: $!");
+       print $out "ref: refs/heads/$branch\n" or
+               error("failed to write $working.git/HEAD: $!");
+       close $out or
+               error("failed to write $working.git/HEAD: $!");
+       return $working;
+}
+
+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 %params = @_;
 
        my $pid = open my $OUT, "-|";
 
 
        my $pid = open my $OUT, "-|";
 
@@ -128,31 +213,68 @@ sub safe_git (&@) {
        if (!$pid) {
                # In child.
                # Git commands want to be in wc.
        if (!$pid) {
                # In child.
                # Git commands want to be in wc.
-               if (! $no_chdir) {
+               if (! @git_dir_stack) {
                        chdir $config{srcdir}
                        chdir $config{srcdir}
-                           or error("Cannot chdir to $config{srcdir}: $!");
+                           or error("cannot chdir to $config{srcdir}: $!");
+               }
+               else {
+                       chdir $git_dir_stack[0]
+                           or error("cannot chdir to $git_dir_stack[0]: $!");
+               }
+
+               if ($params{stdout}) {
+                       open(STDOUT, '>&', $params{stdout}) or error("Cannot reopen stdout: $!");
                }
                }
-               exec @cmdline or error("Cannot exec '@cmdline': $!");
+
+               exec @{$params{cmdline}} or error("Cannot exec '@{$params{cmdline}}': $!");
        }
        # In parent.
 
        }
        # 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>) {
        my @lines;
        while (<$OUT>) {
+               $_=decode_utf8($_, 0);
+
                chomp;
                chomp;
-               push @lines, $_;
+
+               if (! defined $params{data_handler}) {
+                       push @lines, $_;
+               }
+               else {
+                       last unless $params{data_handler}->($_);
+               }
        }
 
        close $OUT;
 
        }
 
        close $OUT;
 
-       $error_handler->("'@cmdline' failed: $!") if $? && $error_handler;
+       $params{error_handler}->("'@{$params{cmdline}}' failed: $!") if $? && $params{error_handler};
 
        return wantarray ? @lines : ($? == 0);
 }
 # Convenient wrappers.
 
        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 ($@) { safe_git(error_handler => \&error, cmdline => \@_) }
+sub run_or_cry ($@) { safe_git(error_handler => sub { warn @_ }, cmdline => \@_) }
+sub run_or_non ($@) { safe_git(cmdline => \@_) }
+
+sub ensure_committer {
+       if (! length $ENV{GIT_AUTHOR_NAME} || ! length $ENV{GIT_COMMITTER_NAME}) {
+               my $name = join('', run_or_non("git", "config", "user.name"));
+               if (! length $name) {
+                       run_or_die("git", "config", "user.name", "IkiWiki");
+               }
+       }
 
 
+       if (! length $ENV{GIT_AUTHOR_EMAIL} || ! length $ENV{GIT_COMMITTER_EMAIL}) {
+               my $email = join('', run_or_non("git", "config", "user.email"));
+               if (! length $email) {
+                       run_or_die("git", "config", "user.email", "ikiwiki.info");
+               }
+       }
+}
 
 sub merge_past ($$$) {
        # Unlike with Subversion, Git cannot make a 'svn merge -rN:M file'.
 
 sub merge_past ($$$) {
        # Unlike with Subversion, Git cannot make a 'svn merge -rN:M file'.
@@ -191,6 +313,8 @@ sub merge_past ($$$) {
        my @undo;      # undo stack for cleanup in case of an error
        my $conflict;  # file content with conflict markers
 
        my @undo;      # undo stack for cleanup in case of an error
        my $conflict;  # file content with conflict markers
 
+       ensure_committer();
+
        eval {
                # Hide local changes from Git by renaming the modified file.
                # Relative paths must be converted to absolute for renaming.
        eval {
                # Hide local changes from Git by renaming the modified file.
                # Relative paths must be converted to absolute for renaming.
@@ -248,15 +372,36 @@ sub merge_past ($$$) {
        return $conflict;
 }
 
        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.
        # 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?
 
        # 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.
 
        my %ci;
        # Header line.
@@ -286,8 +431,9 @@ sub parse_diff_tree ($@) {
                        $ci{ "${who}_epoch" } = $epoch;
                        $ci{ "${who}_tz"    } = $tz;
 
                        $ci{ "${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"} = $1;
                        }
                        elsif ($name =~ m/^([^<]+)\s+<>$/) {
                                $ci{"${who}_username"} = $1;
@@ -319,6 +465,16 @@ sub parse_diff_tree ($@) {
        }
        shift @{ $dt_ref } if $dt_ref->[0] =~ /^$/;
 
        }
        shift @{ $dt_ref } if $dt_ref->[0] =~ /^$/;
 
+       $ci{details} = [parse_changed_files($dt_ref)];
+
+       return \%ci;
+}
+
+sub parse_changed_files {
+       my $dt_ref = shift;
+
+       my @files;
+
        # Modified files.
        while (my $line = shift @{ $dt_ref }) {
                if ($line =~ m{^
        # Modified files.
        while (my $line = shift @{ $dt_ref }) {
                if ($line =~ m{^
@@ -335,16 +491,9 @@ sub parse_diff_tree ($@) {
                        my $sha1_to = shift(@tmp);
                        my $status = shift(@tmp);
 
                        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) {
                        if (length $file) {
-                               push @{ $ci{'details'} }, {
-                                       'file'      => decode("utf8", $file),
+                               push @files, {
+                                       'file'      => decode_git_file($file),
                                        'sha1_from' => $sha1_from[0],
                                        'sha1_to'   => $sha1_to,
                                        'mode_from' => $mode_from[0],
                                        'sha1_from' => $sha1_from[0],
                                        'sha1_to'   => $sha1_to,
                                        'mode_from' => $mode_from[0],
@@ -357,7 +506,7 @@ sub parse_diff_tree ($@) {
                last;
        }
 
                last;
        }
 
-       return \%ci;
+       return @files;
 }
 
 sub git_commit_info ($;$) {
 }
 
 sub git_commit_info ($;$) {
@@ -370,11 +519,10 @@ sub git_commit_info ($;$) {
 
        my @raw_lines = run_or_die('git', 'log', @opts,
                '--pretty=raw', '--raw', '--abbrev=40', '--always', '-c',
 
        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');
+               '-r', $sha1, '--no-renames', '--', '.');
 
        my @ci;
 
        my @ci;
-       while (my $parsed = parse_diff_tree(($prefix or ""), \@raw_lines)) {
+       while (my $parsed = parse_diff_tree(\@raw_lines)) {
                push @ci, $parsed;
        }
 
                push @ci, $parsed;
        }
 
@@ -383,24 +531,72 @@ sub git_commit_info ($;$) {
        return wantarray ? @ci : $ci[0];
 }
 
        return wantarray ? @ci : $ci[0];
 }
 
-sub git_sha1 (;$) {
-       # Return head sha1sum (of given file).
-       my $file = shift || q{--};
+sub rcs_find_changes ($) {
+       my $oldrev=shift;
+
+       # Note that git log will sometimes show files being added that
+       # don't exist. Particularly, git merge -s ours can result in a
+       # merge commit where some files were not really added.
+       # This is why the code below verifies that the files really
+       # exist.
+       my @raw_lines = run_or_die('git', 'log',
+               '--pretty=raw', '--raw', '--abbrev=40', '--always', '-c',
+               '--no-renames', , '--reverse',
+               '-r', "$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 $nullsha) {
+                               if (! -e "$config{srcdir}/$file") {
+                                       delete $changed{$file};
+                                       $deleted{$file}=1;
+                               }
+                       }
+                       else {
+                               if (-e "$config{srcdir}/$file") {
+                                       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 ($sha1) = run_or_non('git', 'rev-list', '--max-count=1', 'HEAD',
        # Ignore error since a non-existing file might be given.
        my ($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
                ($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 () {
        # Update working directory.
 
 }
 
 sub rcs_update () {
        # Update working directory.
 
+       ensure_committer();
+
        if (length $config{gitorigin_branch}) {
        if (length $config{gitorigin_branch}) {
-               run_or_cry('git', 'pull', $config{gitorigin_branch});
+               run_or_cry('git', 'pull', '--prune', $config{gitorigin_branch});
        }
 }
 
        }
 }
 
@@ -409,62 +605,100 @@ sub rcs_prepedit ($) {
        # This will be later used in rcs_commit if a merge is required.
        my ($file) = @_;
 
        # 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.
        # 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.
 
        # 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;
+       if (defined $params{token}) {
+               ($prev) = $params{token} =~ /^($sha1_pattern)$/; # untaint
+       }
 
        if (defined $cur && defined $prev && $cur ne $prev) {
 
        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;
        }
 
                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.
        # 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;
        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 (length $u) {
+                       $u=encode_utf8($u);
+                       $ENV{GIT_AUTHOR_NAME}=$u;
+               }
+               else {
+                       $u = 'anonymous';
+               }
+               if (defined $params{session}->param("nickname")) {
+                       $u=encode_utf8($params{session}->param("nickname"));
+                       $u=~s/\s+/_/g;
+                       $u=~s/[^-_0-9[:alnum:]]+//g;
+               }
+               if (length $u) {
+                       $ENV{GIT_AUTHOR_EMAIL}="$u\@web";
+               }
+               else {
+                       $ENV{GIT_AUTHOR_EMAIL}='anonymous@web';
+               }
        }
 
        }
 
-       $message = IkiWiki::possibly_foolish_untaint($message);
+       ensure_committer();
+
+       $params{message} = IkiWiki::possibly_foolish_untaint($params{message});
        my @opts;
        my @opts;
-       if ($message !~ /\S/) {
+       if ($params{message} !~ /\S/) {
                # Force git to allow empty commit messages.
                # (If this version of git supports it.)
                my ($version)=`git --version` =~ /git version (.*)/;
                # Force git to allow empty commit messages.
                # (If this version of git supports it.)
                my ($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 {
                        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}) {
                if (length $config{gitorigin_branch}) {
-                       run_or_cry('git', 'push', $config{gitorigin_branch});
+                       run_or_cry('git', 'push', $config{gitorigin_branch}, $config{gitmaster_branch});
                }
        }
        
                }
        }
        
@@ -477,7 +711,9 @@ sub rcs_add ($) {
 
        my ($file) = @_;
 
 
        my ($file) = @_;
 
-       run_or_cry('git', 'add', $file);
+       ensure_committer();
+
+       run_or_cry('git', 'add', '--', $file);
 }
 
 sub rcs_remove ($) {
 }
 
 sub rcs_remove ($) {
@@ -485,13 +721,17 @@ sub rcs_remove ($) {
 
        my ($file) = @_;
 
 
        my ($file) = @_;
 
-       run_or_cry('git', 'rm', '-f', $file);
+       ensure_committer();
+
+       run_or_cry('git', 'rm', '-f', '--', $file);
 }
 
 sub rcs_rename ($$) {
        my ($src, $dest) = @_;
 
 }
 
 sub rcs_rename ($$) {
        my ($src, $dest) = @_;
 
-       run_or_cry('git', 'mv', '-f', $src, $dest);
+       ensure_committer();
+
+       run_or_cry('git', 'mv', '-f', '--', $src, $dest);
 }
 
 sub rcs_recentchanges ($) {
 }
 
 sub rcs_recentchanges ($) {
@@ -515,9 +755,12 @@ sub rcs_recentchanges ($) {
                my @pages;
                foreach my $detail (@{ $ci->{'details'} }) {
                        my $file = $detail->{'file'};
                my @pages;
                foreach my $detail (@{ $ci->{'details'} }) {
                        my $file = $detail->{'file'};
+                       my $efile = join('/',
+                               map { uri_escape_utf8($_) } split('/', $file)
+                       );
 
                        my $diffurl = defined $config{'diffurl'} ? $config{'diffurl'} : "";
 
                        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/\[\[sha1_parent\]\]/$ci->{'parent'}/go;
                        $diffurl =~ s/\[\[sha1_from\]\]/$detail->{'sha1_from'}/go;
                        $diffurl =~ s/\[\[sha1_to\]\]/$detail->{'sha1_to'}/go;
@@ -539,7 +782,16 @@ sub rcs_recentchanges ($) {
 
                my $user=$ci->{'author_username'};
                my $web_commit = ($ci->{'author'} =~ /\@web>/);
 
                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] &&
                # compatability code for old web commit messages
                if (! $web_commit &&
                      defined $messages[0] &&
@@ -552,6 +804,7 @@ sub rcs_recentchanges ($) {
                push @rets, {
                        rev        => $sha1,
                        user       => $user,
                push @rets, {
                        rev        => $sha1,
                        user       => $user,
+                       nickname   => $nickname,
                        committype => $web_commit ? "web" : "git",
                        when       => $when,
                        message    => [@messages],
                        committype => $web_commit ? "web" : "git",
                        when       => $when,
                        message    => [@messages],
@@ -564,15 +817,23 @@ sub rcs_recentchanges ($) {
        return @rets;
 }
 
        return @rets;
 }
 
-sub rcs_diff ($) {
+sub rcs_diff ($;$) {
        my $rev=shift;
        my $rev=shift;
+       my $maxlines=shift;
        my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
        my @lines;
        my ($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(
+               error_handler => undef,
+               data_handler => $addlines,
+               cmdline => ["git", "show", $sha1],
+       );
        if (wantarray) {
                return @lines;
        }
        if (wantarray) {
                return @lines;
        }
@@ -581,23 +842,61 @@ sub rcs_diff ($) {
        }
 }
 
        }
 }
 
+{
+my %time_cache;
+
+sub findtimes ($$) {
+       my $file=shift;
+       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);
+
+                               if (! $time_cache{$f}) {
+                                       $time_cache{$f}[0]=$date; # mtime
+                               }
+                               $time_cache{$f}[1]=$date; # ctime
+                       }
+               }
+       }
+
+       return exists $time_cache{$file} ? $time_cache{$file}[$id] : 0;
+}
+
+}
+
 sub rcs_getctime ($) {
        my $file=shift;
 sub rcs_getctime ($) {
        my $file=shift;
-       # Remove srcdir prefix
-       $file =~ s/^\Q$config{srcdir}\E\/?//;
 
 
-       my $sha1  = git_sha1($file);
-       my $ci    = git_commit_info($sha1, 1);
-       my $ctime = $ci->{'author_epoch'};
-       debug("ctime for '$file': ". localtime($ctime));
+       return findtimes($file, 1);
+}
 
 
-       return $ctime;
+sub rcs_getmtime ($) {
+       my $file=shift;
+
+       return findtimes($file, 0);
 }
 
 }
 
-sub rcs_receive () {
+{
+my $ret;
+sub git_find_root {
        # The wiki may not be the only thing in the git repo.
        # Determine if it is in a subdirectory by examining the srcdir,
        # and its parents, looking for the .git directory.
        # The wiki may not be the only thing in the git repo.
        # Determine if it is in a subdirectory by examining the srcdir,
        # and its parents, looking for the .git directory.
+
+       return @$ret if defined $ret;
+       
        my $subdir="";
        my $dir=$config{srcdir};
        while (! -d "$dir/.git") {
        my $subdir="";
        my $dir=$config{srcdir};
        while (! -d "$dir/.git") {
@@ -608,83 +907,201 @@ 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, $path)=File::Temp::tempfile(undef, UNLINK => 1);
+                               safe_git(
+                                       error_handler => sub { error("failed writing temp file '$path': ".shift."."); },
+                                       stdout => $fh,
+                                       cmdline => ['git', 'show', $detail->{sha1_to}],
+                               );
+                       }
+
+                       push @rets, {
+                               file => $file,
+                               action => $action,
+                               path => $path,
+                       };
+               }
+       }
+
+       return @rets;
+}
+
+sub rcs_receive () {
        my @rets;
        while (<>) {
                chomp;
                my ($oldrev, $newrev, $refname) = split(' ', $_, 3);
        my @rets;
        while (<>) {
                chomp;
                my ($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"), $refname);
                }
                # only allow changes to gitmaster_branch
                if ($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.
                # Avoid chdir when running git here, because the changes
                # are in the master git repo, not the srcdir repo.
-               # The pre-recieve 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"), $file);
-                               }
+               # (Also, if a subdir is involved, we don't want to chdir to
+               # it and only see changes in it.)
+               # The pre-receive hook already puts us in the right place.
+               in_git_dir(".", sub {
+                       push @rets, git_parse_changes(0, git_commit_info($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'};
-                               }
-                               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 $detail->{'mode_to'}) {
-                                               error gettext("you are not allowed to change file modes");
-                                       }
-                               }
-                               
-                               # extract attachment to temp file
-                               if (($action eq 'add' || $action eq 'change') &&
-                                    ! pagetype($file)) {
-                                       eval q{use File::Temp};
-                                       die $@ if $@;
-                                       my $fh;
-                                       ($fh, $path)=File::Temp::tempfile("XXXXXXXXXX", UNLINK => 1);
-                                       if (system("git show ".$detail->{sha1_to}." > '$path'") != 0) {
-                                               error("failed writing temp file");
-                                       }
-                               }
+       return reverse @rets;
+}
 
 
-                               push @rets, {
-                                       file => $file,
-                                       action => $action,
-                                       path => $path,
-                               };
+sub rcs_preprevert ($) {
+       my $rev=shift;
+       my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+       my @undo;      # undo stack for cleanup in case of an error
+
+       ensure_committer();
+
+       # Examine changes from root of git repo, not from any subdir,
+       # in order to see all changes.
+       my ($subdir, $rootdir) = git_find_root();
+       return in_git_dir($rootdir, sub {
+               my @commits=git_commit_info($sha1, 1);
+       
+               if (! @commits) {
+                       error "unknown commit"; # just in case
+               }
+
+               # 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");
+               }
+
+               # Due to the presence of rename-detection, we cannot actually
+               # see what will happen in a revert without trying it.
+               # But we can guess, which is enough to rule out most changes
+               # that we won't allow reverting.
+               git_parse_changes(1, @commits);
+
+               my $failure;
+               my @ret;
+               eval {
+                       my $branch = "ikiwiki_revert_${sha1}"; # supposed to be unique
+
+                       push @undo, sub {
+                               run_or_cry('git', 'branch', '-D', $branch) if $failure;
+                       };
+                       if (run_or_non('git', 'rev-parse', '--quiet', '--verify', $branch)) {
+                               run_or_non('git', 'branch', '-D', $branch);
                        }
                        }
+                       run_or_die('git', 'branch', $branch, $config{gitmaster_branch});
+
+                       my $working = create_temp_working_dir($rootdir, $branch);
+
+                       push @undo, sub {
+                               remove_tree($working);
+                       };
+
+                       in_git_dir($working, sub {
+                               run_or_die('git', 'checkout', '--quiet', '--force', $branch);
+                               run_or_die('git', 'revert', '--no-commit', $sha1);
+                               run_or_die('git', 'commit', '-m', "revert $sha1", '-a');
+                       });
+
+                       my @raw_lines;
+                       @raw_lines = run_or_die('git', 'diff', '--pretty=raw',
+                               '--raw', '--abbrev=40', '--always', '--no-renames',
+                               "..${branch}");
+
+                       my $ci = {
+                               details => [parse_changed_files(\@raw_lines)],
+                       };
+
+                       @ret = git_parse_changes(0, $ci);
+               };
+               $failure = $@;
+
+               # Process undo stack (in reverse order).  By policy cleanup
+               # actions should normally print a warning on failure.
+               while (my $handle = pop @undo) {
+                       $handle->();
                }
                }
-       }
 
 
-       return reverse @rets;
+               if ($failure) {
+                       my $message = sprintf(gettext("Failed to revert commit %s"), $sha1);
+                       error("$message\n$failure\n");
+               }
+
+               return @ret;
+       });
+}
+
+sub rcs_revert ($) {
+       # Try to revert the given rev; returns undef on _success_.
+       my $rev = shift;
+       my ($sha1) = $rev =~ /^($sha1_pattern)$/; # untaint
+
+       ensure_committer();
+
+       if (run_or_non('git', 'cherry-pick', '--no-commit', "ikiwiki_revert_$sha1")) {
+               return undef;
+       }
+       else {
+               run_or_non('git', 'branch', '-D', "ikiwiki_revert_$sha1");
+               return sprintf(gettext("Failed to revert commit %s"), $sha1);
+       }
 }
 
 1
 }
 
 1