add pesco's darcs plugin

1 files changed, 509 insertions, 0 deletions

diff --git a/IkiWiki/Plugin/darcs.pm b/IkiWiki/Plugin/darcs.pm
new file mode 100644
index 000000000..0957ef0ef
--- /dev/null
+++ b/IkiWiki/Plugin/darcs.pm
@@ -0,0 +1,509 @@
+# Support for the darcs rcs, <URL:http://darcs.net/>.
+# Copyright (C) 2006  Thomas Schwinge <tschwinge@gnu.org>
+#               2007  Benjamin A'Lee <bma@bmalee.eu>
+#                     Tuomo Valkonen <tuomov@iki.fi>
+#               2008  Simon Michael <simon@joyful.com>
+#                     Petr Ročkai <me@mornfall.net>
+#                     Sven M. Hallberg <pesco@khjk.org>
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation; either version 2 of the License, or (at your
+# option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+# History (see http://ikiwiki.info/todo/darcs/):
+#
+#  * Thomas Schwinge wrote the original file, implementing only rcs_commit.
+#  * Benjamin A'Lee contributed an alternative implementation.
+#  * Tuomo Valkonen contributed rcs_getctime and stub rcs_recentchanges.
+#  * Simon Michael contributed multiple changes.
+#  * Petr Ročkai fixed rcs_recentchanges and added caching to rcs_getctime.
+#  * Sven M. Hallberg merged the above and added missing features.
+
+
+# We're guaranteed to be the only instance of ikiwiki running at a given
+# time.  It is essential that only ikiwiki is working on a particular
+# repository.  That means one instance of ikiwiki and it also means that
+# you must not 'darcs push' into this repository, as this might create
+# race conditions, as I understand it.
+
+
+package IkiWiki::Plugin::darcs;
+
+use warnings;
+use strict;
+use IkiWiki;
+
+
+sub import {
+    hook(type => "checkconfig", id => "darcs", call => \&checkconfig);
+    hook(type => "getsetup", id => "darcs", call => \&getsetup);
+    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_commit_staged", call => \&rcs_commit_staged);
+    hook(type => "rcs", id => "rcs_add", call => \&rcs_add);
+    hook(type => "rcs", id => "rcs_remove", call => \&rcs_remove);
+    hook(type => "rcs", id => "rcs_rename", call => \&rcs_rename);
+    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);
+}
+
+
+# Which darcs executable to use.
+my $darcs = ($ENV{DARCS} or 'darcs');
+
+
+# Internal functions
+
+our %cache;
+
+sub loadcache () {
+    my $repodir=$config{srcdir};
+    if (!defined %cache) {
+        my $f = "$repodir/.ikiwiki.ctimes";
+        if (-s "$f") {
+            my $VAR1;
+            my $x = `cat "$f"`;
+            $x =~ /^(.*)$/sm; # untaint
+            eval "$1";
+            %cache = %$VAR1;
+        }
+    }
+}
+
+END {
+    my $repodir=$config{srcdir};
+    if (defined %cache) {
+        debug("dumping ctime cache to $repodir/.ikiwiki.ctimes");
+        open CACHE, ">$repodir/.ikiwiki.ctimes";
+        print CACHE Dumper(\%cache);
+        close CACHE;
+    }
+}
+
+sub silentsystem (@) {
+    open(SAVED_STDOUT, ">&STDOUT");
+    open(STDOUT, ">/dev/null");
+    my $ret = system @_;
+    open(STDOUT, ">&SAVED_STDOUT");
+    return $ret;
+}
+
+sub darcs_info ($$$) {
+    my $field = shift;
+    my $repodir = shift;
+    my $file = shift; # Relative to the repodir.
+
+    my $child = open(DARCS_CHANGES, "-|");
+    if (! $child) {
+    exec($darcs, 'changes', '--repodir', $repodir, '--xml-output', $file) or
+        error("failed to run 'darcs changes'");
+    }
+
+    # Brute force for now.  :-/
+    while (<DARCS_CHANGES>) {
+    last if /^<\/created_as>$/;
+    }
+    ($_) = <DARCS_CHANGES> =~ /$field=\'([^\']+)/;
+    $field eq 'hash' and s/\.gz//; # Strip away the '.gz' from 'hash'es.
+
+    close(DARCS_CHANGES) or error("'darcs changes' exited " . $?);
+
+    return $_;
+}
+
+sub darcs_rev($) {
+    my $file = shift; # Relative to the repodir.
+    my $repodir = $config{srcdir};
+
+    my $child = open(DARCS_MANIFEST, "-|");
+    if (! $child) {
+        exec($darcs, 'query', 'manifest', '--repodir', $repodir) or
+            error("failed to run 'darcs query manifest'");
+    }
+    my $found=0;
+    while (<DARCS_MANIFEST>) {
+        $found = 1, last if /^$file$/;
+    }
+    return "" if (! $found);
+    close(DARCS_MANIFEST) or error("'darcs query manifest' exited " . $?);
+
+    my $hash = darcs_info('hash', $repodir, $file);
+    return defined $hash ? $hash : "";
+}
+
+
+# Exported functions.
+
+sub checkconfig() {
+    if (defined $config{darcs_wrapper} && length $config{darcs_wrapper}) {
+	push @{$config{wrappers}}, {
+	    wrapper => $config{darcs_wrapper},
+	    wrappermode => (defined $config{darcs_wrappermode} ? $config{darcs_wrappermode} : "06755"),
+	};
+    }
+}
+
+sub getsetup() {
+    return
+	plugin => {
+	    safe => 0, # rcs plugin
+	    rebuild => undef,
+	},
+	darcs_wrapper => {
+	    type => "string",
+	    example => "/darcs/repo/_darcs/ikiwiki-wrapper",
+	    description => "wrapper to generate (set as master repo apply hook)",
+	    safe => 0, # file
+	    rebuild => 0,
+	},
+	darcs_wrappermode => {
+	    type => "string",
+	    example => '06755',
+	    description => "mode for darcs_wrapper (can safely be made suid)",
+	    safe => 0,
+	    rebuild => 0,
+	},
+	historyurl => {
+	    type => "string",
+	    example => "http://darcs.example.com/darcsweb.cgi?r=wiki;a=filehistory;f=[[file]]",
+	    description => "darcsweb url to show file history ([[file]] substituted)",
+	    safe => 1,
+	    rebuild => 1,
+	},
+	diffurl => {
+	    type => "string",
+	    example => "http://darcs.example.com/darcsweb.cgi?r=wiki;a=filediff;h=[[hash]];f=[[file]]",
+	    description => "darcsweb url to show a diff ([[hash]] and [[file]] substituted)",
+	    safe => 1,
+	    rebuild => 1,
+	},
+}
+
+sub rcs_update () {
+    silentsystem($darcs, "pull", "--repodir", $config{srcdir}, "-qa")
+}
+
+sub rcs_prepedit ($) {
+    # Prepares to edit a file under revision control.  Returns a token that
+    # must be passed to rcs_commit() when the file is to be commited.  For us,
+    # this token the hash value of the latest patch that modifies the file,
+    # i.e. something like its current revision.  If the file is not yet added
+    # to the repository, we return TODO: the empty string.
+
+    my $file = shift; # Relative to the repodir.
+    my $rev = darcs_rev($file);
+    return $rev;
+}
+
+sub rcs_commit ($$$;$$) {
+    # Commit the page.  Returns 'undef' on success and a version of the page
+    # with conflict markers on failure.
+
+    my ($file, $message, $rcstoken, $user, $ipaddr) = @_;
+
+    # Compute if the "revision" of $file changed.
+    my $changed = darcs_rev($file) ne $rcstoken;
+
+    # Yes, the following is a bit convoluted.
+    if ($changed) {
+    # TODO.  Invent a better, non-conflicting name.
+    rename("$config{srcdir}/$file", "$config{srcdir}/$file.save") or
+        error("failed to rename $file to $file.save: $!");
+
+    # Roll the repository back to $rcstoken.
+
+    # TODO.  Can we be sure that no changes are lost?  I think that
+    # we can, if we make sure that the 'darcs push' below will always
+    # succeed.
+
+    # We need to revert everything as 'darcs obliterate' might choke
+    # otherwise.
+        # TODO: 'yes | ...' needed?  Doesn't seem so.
+    silentsystem($darcs, "revert", "--repodir", $config{srcdir}, "--all") and
+        error("'darcs revert' failed");
+    # Remove all patches starting at $rcstoken.
+    my $child = open(DARCS_OBLITERATE, "|-");
+    if (! $child) {
+        open(STDOUT, ">/dev/null");
+        exec($darcs, "obliterate", "--repodir", $config{srcdir},
+           "--match", "hash " . $rcstoken) and
+           error("'darcs obliterate' failed");
+    }
+    while (print DARCS_OBLITERATE "y") {
+        ;
+    }
+    close(DARCS_OBLITERATE);
+    # Restore the $rcstoken one.
+    silentsystem($darcs, "pull", "--quiet", "--repodir", $config{srcdir},
+           "--match", "hash " . $rcstoken, "--all") and
+           error("'darcs pull' failed");
+
+    # We're back at $rcstoken.  Re-install the modified file.
+    rename("$config{srcdir}/$file.save", "$config{srcdir}/$file") or
+        error("failed to rename $file.save to $file: $!");
+    }
+
+    # Record the changes.
+    my $author;
+    if (defined $user) {
+        $author = "$user\@web";
+    } elsif (defined $ipaddr) {
+        $author = "$ipaddr\@web";
+    } else {
+        $author = "anon\@web";
+    }
+    if (!defined $message || !length($message)) {
+        $message = "empty message";
+    }
+    silentsystem($darcs, 'record', '--repodir', $config{srcdir}, '--all',
+       '-m', $message, '--author', $author, $file) and
+           error("'darcs record' failed");
+
+    # Update the repository by pulling from the default repository, which is
+    # master repository.
+    silentsystem($darcs, "pull", "--quiet", "--repodir", $config{srcdir},
+       "--all") and error("'darcs pull' failed");
+
+    # If this updating yields any conflicts, we'll record them now to resolve
+    # them.  If nothing is recorded, there are no conflicts.
+    $rcstoken = darcs_rev($file);
+    # TODO: Use only the first line here, i.e. only the patch name?
+    writefile("$file.log", $config{srcdir}, 'resolve conflicts: ' . $message);
+    silentsystem($darcs, 'record', '--repodir', $config{srcdir}, '--all',
+       '-m', 'resolve conflicts: ' . $message, '--author', $author, $file) and
+           error("'darcs record' failed");
+    my $conflicts = darcs_rev($file) ne $rcstoken;
+    unlink("$config{srcdir}/$file.log") or
+    error("failed to remove '$file.log'");
+
+    # Push the changes to the main repository.
+    silentsystem($darcs, 'push', '--quiet', '--repodir', $config{srcdir}, '--all')
+    and error("'darcs push' failed");
+    # TODO: darcs send?
+
+    if ($conflicts) {
+        my $document = readfile("$config{srcdir}/$file");
+        # Try to leave everything in a consistent state.
+        # TODO: 'yes | ...' needed?  Doesn't seem so.
+        silentsystem($darcs, "revert", "--repodir", $config{srcdir}, "--all") and
+            warn("'darcs revert' failed");
+        return $document;
+    } else {
+        return undef;
+    }
+}
+
+sub rcs_commit_staged($$$) {
+    my ($message, $user, $ipaddr) = @_;
+
+    my $author;
+    if (defined $user) {
+        $author = "$user\@web";
+    } elsif (defined $ipaddr) {
+        $author = "$ipaddr\@web";
+    } else {
+        $author = "anon\@web";
+    }
+    if (!defined $message || !length($message)) {
+        $message = "empty message";
+    }
+
+    silentsystem($darcs, "record", "--repodir", $config{srcdir}, "-a", "-A", $author,
+	"-m", $message)	and error("'darcs record' failed");
+
+    # Push the changes to the main repository.
+    silentsystem($darcs, 'push', '--quiet', '--repodir', $config{srcdir}, '--all')
+    and error("'darcs push' failed");
+    # TODO: darcs send?
+
+    return undef;
+}
+
+sub rcs_add ($) {
+    my $file = shift; # Relative to the repodir.
+
+    # Intermediate directories will be added automagically.
+    system($darcs, 'add', '--quiet', '--repodir', $config{srcdir},
+       '--boring', $file) and error("'darcs add' failed");
+}
+
+sub rcs_remove ($) {
+    my $file = shift; # Relative to the repodir.
+
+    system('rm', $config{srcdir}.'/'.$file)
+       and error("'rm' failed");
+}
+
+sub rcs_rename ($$) {
+    my $a = shift; # Relative to the repodir.
+    my $b = shift; # Relative to the repodir.
+
+    system($darcs, 'mv', '--repodir', $config{srcdir}, $a, $b)
+       and error("'darcs mv' failed");
+}
+
+sub rcs_recentchanges ($) {
+    my $num=shift;
+    my @ret;
+
+    eval q{use Date::Parse};
+    eval q{use XML::Simple};
+
+    my $repodir=$config{srcdir};
+
+    debug("darcs recent changes: $num");
+
+    my $child = open(LOG, "-|");
+    if (! $child) {
+        $ENV{"DARCS_DONT_ESCAPE_ANYTHING"}=1;
+        exec("darcs", "changes", "--xml", 
+            "--summary",
+             "--repodir", "$repodir",
+             "--last", "$num")
+        || error("'darcs changes' failed to run");
+    }
+    my $data;
+    $data .= $_ while(<LOG>);
+    close LOG;
+
+    my $log = XMLin($data, ForceArray => 1);
+
+    debug("parsing recent changes...");
+    foreach my $patch (@{$log->{patch}}) {
+        my $date=$patch->{local_date};
+        my $hash=$patch->{hash};
+        my $when=str2time($date);
+        my (@pages, @files, @pg);
+        push @pages, $_ for (@{$patch->{summary}->[0]->{modify_file}});
+        push @pages, $_ for (@{$patch->{summary}->[0]->{add_file}});
+        push @pages, $_ for (@{$patch->{summary}->[0]->{remove_file}});
+        for (@pages) {
+            my $f = $_;
+            $f = $_->{content} if (ref $_);
+            $f =~ s,^\s+,,; $f =~ s,\s+$,,; # cut whitespace
+
+	    push @files, $f;
+        }
+	for (@{$patch->{summary}->[0]->{move}}) {
+	    my $p = $_;
+	    push @files, $p->{from};
+        }
+
+	for (@files) {
+	    my $f = $_;
+	    my $d = defined $config{'diffurl'} ? $config{'diffurl'} : "";
+	    $d =~ s/\[\[file\]\]/$f/go;
+	    $d =~ s/\[\[hash\]\]/$hash/go;
+
+            debug("file: $f");
+	    debug("diffurl: $d");
+            push @pg, {
+                page => pagename($f),
+		diffurl => $d,
+            };
+        }
+        next unless (scalar @pg > 0);
+        debug("recent change: " . $patch->{name}[0] . " ("
+            . scalar @pg . " changes)");
+
+        my @message;
+        push @message, { line => $_ } for (@{$patch->{name}});
+
+        my $committype;
+        if ($patch->{author} =~ /\@web$/) {
+            $committype = "web";
+        } else {
+            $committype = "darcs";
+        }
+
+        push @ret, {
+            rev => $patch->{hash},
+            user => $patch->{author},
+            committype => $committype,
+            when => $when, 
+            message => [@message],
+            pages => [@pg],
+        };
+    }
+
+    return @ret;
+}
+
+sub rcs_diff ($) {
+    my $rev=shift;
+    my @lines;
+    foreach my $line (silentsystem("darcs", "diff", "--match", "hash ".$rev)) {
+	if (@lines || $line=~/^diff/) {
+	    push @lines, $line."\n";
+        }
+    }
+    if (wantarray) {
+	return @lines;
+    }
+    else {
+	return join("", @lines);
+    }
+}
+
+sub rcs_getctime ($) {
+    my $file=shift;
+
+    eval q{use Date::Parse};
+    eval q{use XML::Simple};
+    local $/=undef;
+
+    # Sigh... doing things the hard way again
+    my $repodir=$config{srcdir};
+
+    &loadcache;
+
+    my $filer=substr($file, length($repodir));
+    $filer =~ s:^[/]+::;
+
+    if (defined $cache{$filer}) {
+        #debug("taking cached ctime ".localtime($cache{$filer})." for $filer");
+        return $cache{$filer};
+    }
+
+    my $child = open(LOG, "-|");
+    if (! $child) {
+        exec("darcs", "changes", "--xml", "--reverse",
+             "--repodir", "$repodir", "$filer")
+        || error("'darcs changes $filer' failed to run");
+    }
+
+    my $data;
+    $data .= $_ while(<LOG>);
+    close LOG;
+
+    my $log = XMLin($data, ForceArray => 1);
+
+    my $datestr=$log->{patch}[0]->{local_date};
+
+    if (! defined $datestr) {
+        warn "failed to get ctime for $filer";
+        $cache{$filer} = 0;
+        return 0;
+    }
+
+    my $date=str2time($datestr);
+
+    #debug("found ctime ".localtime($date)." for $filer");
+
+    $cache{$filer} = $date;
+    return $date;
+}
+
+1