psyced/utility/multipatcher

#!/usr/bin/perl
# recursive cvs root fixer. reusable for all sorts of patch operations. -lynX

require 'find.pl';
$File::Find::dont_use_nlink = 'DONT!';

my $op = "s#^:pserver:anonymous\@cvs\.psyced\.org:/CVS/anonCVS#:pserver:$ENV{USER}\@cvs\.psyced\.org:/CVS/muveCVS#m";

$grep = shift or die <<X;

usage: $0 <filematch> [<operation> [<directories>]]

<filematch> would typically be "Root"

<operation> by default is to transform anonymous access to the psyced
	    repository into your personal login access. in detail:

	"s#^:pserver:anonymous\\\@cvs\\\.psyced\\\.org:/CVS/anonCVS#:pserver:$ENV{USER}\\\@cvs\\\.psyced\\\.org:/CVS/muveCVS#m"

without <directories> the directory tree starting from the current directory
is recursively checked.

you can obviously use a completely different regular expression on completely
different sets of files. for example here is a command that will remove the
/lastlog store from all of psyced's .o save files it encounters.

	multipatcher '.o' 's:^_log .*\\n\$::m'

you can even embed any of \$name, \$dir or \$base, like this:

	multipatcher .o 's#softnews#id":"psyc://psyced.org/~$base","softnews#'

this one inserts an entry 'id' in front of an existing entry called 'softnews'
X

$_ = shift;
$op = $_ if $_;

$|=1;
my @list;
&find($#ARGV >= 0 ? @ARGV : '.');
exit;

sub wanted {
	($dev,$ino,$mode,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime)
		= lstat;
	return unless /$grep/o;

	my $f = $_;
	if (open(I, $f)) {
		$_ = &slurp(I);
		close I;
	} else {
		print STDERR "cannot access $name\n";
		return;
	}
	my $base = $f =~ m!^(\w+)\b! ? $1 : $f;

	my $was = $_;
	eval $op;
#	print "** $op ** in $_ **\n";

	if ($was eq $_) {
		print "no:\t$name\n";
		return;
	}
	print "yes:\t$name\n";

	if (open(O, ">Nu$f")) {
		print O $_;
		close O;
	} else {
		print STDERR "cannot create Nu$f in $dir\n";
		return;
	}
	unless (unlink $f) {
		print STDERR "cannot delete $f\n";
		return;
	}
	rename ("Nu$f", $f) or die "the world is not logical";
}

# reads a file from a stream into a variable all at once
#
sub slurp {
	local(*IN) = @_;
	local($save) = $/;
	undef $/;
	local($data) = <IN>;
	$/ = $save;
	return $data;
}