Here's Thomas Schwinge unfinished darcs support for ikiwiki.
> I haven't been working on this for months and also won't in the near
> future. Feel free to use what I have done so
> far and bring it into an usable state! Also, feel free to contact me
> if there are questions.
-- [Thomas Schwinge](mailto:tschwinge@gnu.org)
# Support for the darcs rcs, .
# Copyright (C) 2006 Thomas Schwinge
#
# 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.
# 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.
use warnings;
use strict;
use IkiWiki;
package IkiWiki;
# Which darcs executable to use.
my $darcs = ($ENV{DARCS} or 'darcs');
# Internal functions.
sub darcs_info ($$$) {
my $field = shift;
my $repodir = shift;
my $file = shift; # Relative to the repodir.
my $child = open(DARCS_CHANGES, "-|");
if (! $child) {
exec($darcs, 'changes', '--repo=' . $repodir, '--xml-output', $file) or
error('failed to run `darcs changes\'');
}
# Brute force for now. :-/
while () {
last if /^<\/created_as>$/;
}
($_) = =~ /$field=\'([^\']+)/;
$field eq 'hash' and s/\.gz//; # Strip away the `.gz' from `hash'es.
close(DARCS_CHANGES) or error('`darcs changes\' exited ' . $?);
return $_;
}
# Exported functions.
sub rcs_update () {
# Not needed.
}
sub rcs_prepedit ($) {
# Prepares to edit a file under revision control. Returns a token that
# must be passed to rcs_commit() when the file is to be commited. For us,
# this token the hash value of the latest patch that modifies the file,
# i.e. something like its current revision. If the file is not yet added
# to the repository, we return TODO: the empty string.
my $file = shift; # Relative to the repodir.
my $hash = darcs_info('hash', $config{srcdir}, $file);
return defined $hash ? $hash : "";
}
sub rcs_commit ($$$) {
# Commit the page. Returns `undef' on success and a version of the page
# with conflict markers on failure.
my $file = shift; # Relative to the repodir.
my $message = shift;
my $rcstoken = shift;
# Compute if the ``revision'' of $file changed.
my $changed = darcs_info('hash', $config{srcdir}, $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 $rcstoken.
# TODO. Can we be sure that no changes are lost? I think that
# we can, if we make sure that the `darcs push' below will always
# succeed.
# We need to revert everything as `darcs obliterate' might choke
# otherwise.
# TODO: `yes | ...' needed? Doesn't seem so.
system($darcs, "revert", "--repodir=" . $config{srcdir}, "--all") and
error("`darcs revert' failed");
# Remove all patches starting at $rcstoken.
# TODO. Something like `yes | darcs obliterate ...' seems to be needed.
system($darcs, "obliterate", "--quiet", "--repodir" . $config{srcdir},
"--match", "hash " . $rcstoken) and
error("`darcs obliterate' failed");
# Restore the $rcstoken one.
system($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.
# TODO: What if $message is empty?
writefile("$file.log", $config{srcdir}, $message);
system($darcs, 'record', '--repodir=' . $config{srcdir}, '--all',
'--logfile=' . "$config{srcdir}/$file.log",
'--author=' . 'web commit ', $file) and
error('`darcs record\' failed');
# Update the repository by pulling from the default repository, which is
# master repository.
system($darcs, "pull", "--quiet", "--repodir=" . $config{srcdir},
"--all") and error("`darcs pull' failed\n");
# If this updating yields any conflicts, we'll record them now to resolve
# them. If nothing is recorded, there are no conflicts.
$rcstoken = darcs_info('hash', $config{srcdir}, $file);
# TODO: Use only the first line here, i.e. only the patch name?
writefile("$file.log", $config{srcdir}, 'resolve conflicts: ' . $message);
system($darcs, 'record', '--repodir=' . $config{srcdir}, '--all',
'--logfile=' . "$config{srcdir}/$file.log",
'--author=' . 'web commit ', $file) and
error('`darcs record\' failed');
my $conflicts = darcs_info('hash', $config{srcdir}, $file) ne $rcstoken;
unlink("$config{srcdir}/$file.log") or
error("failed to remove `$file.log'");
# Push the changes to the main repository.
system($darcs, 'push', '--quiet', '--repodir=' . $config{srcdir}, '--all')
and error('`darcs push\' failed');
# TODO: darcs send?
if ($conflicts) {
my $document = readfile("$config{srcdir}/$file");
# Try to leave everything in a consistent state.
# TODO: `yes | ...' needed? Doesn't seem so.
system($darcs, "revert", "--repodir=" . $config{srcdir}, "--all") and
warn("`darcs revert' failed.\n");
return $document;
} else {
return undef;
}
}
sub rcs_add ($) {
my $file = shift; # Relative to the repodir.
# Intermediate directories will be added automagically.
system($darcs, 'add', '--quiet', '--repodir=' . $config{srcdir},
'--boring', $file) and error('`darcs add\' failed');
}
sub rcs_recentchanges ($) {
warn('rcs_recentchanges() is not implemented');
return 'rcs_recentchanges() is not implemented';
}
sub rcs_notify () {
warn('rcs_notify() is not implemented');
}
sub rcs_getctime () {
warn('rcs_getctime() is not implemented');
}
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