+} #}}}
+
+sub modifyconfig { #{{{
+ my $f=shift;
+ # the section to modify or add
+ my $targetsection=shift;
+ # fields to change in the section
+ # To remove a field, set its value to "".
+ my %changefields=@_;
+
+ my @lines;
+ my @out;
+
+ if (-e $f) {
+ open(my $in, "<", $f) || die "mr: open $f: $!\n";
+ @lines=<$in>;
+ close $in;
+ }
+
+ my $formatfield=sub {
+ my $field=shift;
+ my @value=split(/\n/, shift);
+
+ return "$field = ".shift(@value)."\n".
+ join("", map { "\t$_\n" } @value);
+ };
+ my $addfields=sub {
+ my @blanks;
+ while ($out[$#out] =~ /^\s*$/) {
+ unshift @blanks, pop @out;
+ }
+ foreach my $field (sort keys %changefields) {
+ if (length $changefields{$field}) {
+ push @out, "$field = $changefields{$field}\n";
+ delete $changefields{$field};
+ }
+ }
+ push @out, @blanks;
+ };
+
+ my $section;
+ while (@lines) {
+ $_=shift(@lines);
+
+ if (/^\s*\#/ || /^\s*$/) {
+ push @out, $_;
+ }
+ elsif (/^\[([^\]]*)\]\s*$/) {
+ if (defined $section &&
+ $section eq $targetsection) {
+ $addfields->();
+ }
+
+ $section=$1;
+
+ push @out, $_;
+ }
+ elsif (/^(\w+)\s*=\s(.*)/) {
+ my $parameter=$1;
+ my $value=$2;
+
+ # continued value
+ while (@lines && $lines[0]=~/^\s(.+)/) {
+ shift(@lines);
+ $value.="\n$1";
+ chomp $value;
+ }
+
+ if ($section eq $targetsection) {
+ if (exists $changefields{$parameter}) {
+ if (length $changefields{$parameter}) {
+ $value=$changefields{$parameter};
+ }
+ delete $changefields{$parameter};
+ }
+ }
+
+ push @out, $formatfield->($parameter, $value);
+ }
+ }
+
+ if (defined $section &&
+ $section eq $targetsection) {
+ $addfields->();
+ }
+ elsif (%changefields) {
+ push @out, "\n[$targetsection]\n";
+ foreach my $field (sort keys %changefields) {
+ if (length $changefields{$field}) {
+ push @out, $formatfield->($field, $changefields{$field});
+ }
+ }
+ }
+
+ open(my $out, ">", $f) || die "mr: write $f: $!\n";
+ print $out @out;
+ close $out;
+} #}}}
+
+sub help { #{{{
+ exec($config{''}{DEFAULT}{$action}) || die "exec: $!";
+} #}}}
+
+sub config { #{{{
+ if (@_ < 2) {
+ die "mr config: not enough parameters\n";
+ }
+ my $section=shift;
+ if ($section=~/^\//) {
+ # try to convert to a path relative to the config file
+ my ($dir)=$ENV{MR_CONFIG}=~/^(.*\/)[^\/]+$/;
+ $dir=abs_path($dir);
+ $dir.="/" unless $dir=~/\/$/;
+ if ($section=~/^\Q$dir\E(.*)/) {
+ $section=$1;
+ }
+ }
+ my %changefields;
+ foreach (@_) {
+ if (/^([^=]+)=(.*)$/) {
+ $changefields{$1}=$2;
+ }
+ else {
+ my $found=0;
+ foreach my $topdir (sort keys %config) {
+ if (exists $config{$topdir}{$section} &&
+ exists $config{$topdir}{$section}{$_}) {
+ print $config{$topdir}{$section}{$_}."\n";
+ $found=1;
+ last if $section eq 'DEFAULT';
+ }
+ }
+ if (! $found) {
+ die "mr $action: $section $_ not set\n";
+ }
+ }
+ }
+ modifyconfig($ENV{MR_CONFIG}, $section, %changefields) if %changefields;
+ exit 0;
+} #}}}
+
+sub register { #{{{
+ if (! $config_overridden) {
+ # Find the closest known mrconfig file to the current
+ # directory.
+ $directory.="/" unless $directory=~/\/$/;
+ foreach my $topdir (reverse sort keys %config) {
+ next unless length $topdir;
+ if ($directory=~/^\Q$topdir\E/) {
+ $ENV{MR_CONFIG}=$configfiles{$topdir};
+ $directory=$topdir;
+ last;
+ }
+ }
+ }
+ if (@ARGV) {
+ my $subdir=shift @ARGV;
+ if (! chdir($subdir)) {
+ print STDERR "mr $action: failed to chdir to $subdir: $!\n";
+ }
+ }
+
+ $ENV{MR_REPO}=getcwd();
+ my $command=findcommand("register", $ENV{MR_REPO}, $directory, 'DEFAULT');
+ if (! defined $command) {
+ die "mr $action: unknown repository type\n";
+ }
+
+ $ENV{MR_REPO}=~s/.*\/(.*)/$1/;
+ $command="set -e; ".$config{$directory}{DEFAULT}{lib}."\n".
+ "my_action(){ $command\n }; my_action ".
+ join(" ", map { s/\//\/\//g; s/"/\"/g; '"'.$_.'"' } @ARGV);
+ print "mr $action: running >>$command<<\n" if $verbose;
+ exec($command) || die "exec: $!";
+} #}}}
+
+# alias expansion and command stemming
+sub expandaction { #{{{
+ my $action=shift;
+ if (exists $alias{$action}) {
+ $action=$alias{$action};
+ }
+ if (! exists $knownactions{$action}) {
+ my @matches = grep { /^\Q$action\E/ }
+ keys %knownactions, keys %alias;
+ if (@matches == 1) {
+ $action=$matches[0];
+ }
+ elsif (@matches == 0) {
+ die "mr: unknown action \"$action\" (known actions: ".
+ join(", ", sort keys %knownactions).")\n";
+ }
+ else {
+ die "mr: ambiguous action \"$action\" (matches: ".
+ join(", ", @matches).")\n";
+ }
+ }
+ return $action;