#! /usr/bin/perl -w
$^W = 1; # same as -w above

# (C) Copyright 2003 Rahul Dhesi, All rights reserved.
#
# "As is" -- No warranty.
#
# Copying, use, and modification are permitted, governed by
# the GNU General Public License, by only those who agree
# to use this program at their own risk.

use strict;

# unbuffered output is usually desired
$| = 1;

# $Source: /mi/maincvs/mail/pfdiff,v $
# $Id: pfdiff,v 1.7 2003/01/20 09:21:26 dhesi Exp $
#
# Give a diff of two Postfix instances

$::myname = $0;
$::myname =~ s|.*/||;

$::RCSHEADER = '$Source: /mi/maincvs/mail/pfdiff,v $' . "\n" .
	'$Id: pfdiff,v 1.7 2003/01/20 09:21:26 dhesi Exp $';

# suppresss perl warnings
$::debug = $::opt_x = undef;
$::ddebug = $::opt_X = undef;
$::verbose = $::opt_v = undef;
$::trace = $::opt_t = undef;
$::opt_h = undef;
$::opt_u = undef;
$::opt_c = undef;
$::opt_s = undef;
$::opt_b = undef;

$::usage = "usage: $::myname [-vtx] cfdir1 cfdir2 (or -h for help)";
if (@ARGV && $ARGV[0] =~ "^-.+" ) {
  local($^W) = 0;		# suppress annoying undef warnings
  require "getopts.pl";
  &Getopts("vtxXhucsbZ");		# Z will suppress perl warning
}

$::ddebug = $::opt_X;			# debug
$::debug = $::opt_x || $::ddebug;	# extended debug
$::trace = $::opt_t;
$::verbose = $::debug || $::trace || $::opt_v;
if ($::opt_h) {
  &givehelp();
  exit(0);
}

(@ARGV != 2) && &usage_error;

# program goes here
my $t1 = "/tmp/pfdifft1$$";
my $t2 = "/tmp/pfdifft2$$";

END { defined($t1) && unlink $t1;  defined($t2) && unlink $t2; }

my $d1 = shift;
my $d2 = shift;

-d $d1 || die "$::myname: error: $d1: not a directory\n";
-d $d2 || die "$::myname: error: $d2: not a directory\n";

-e "$d1/main.cf" || die "$::myname: error: $d1/main.cf: $!\n";
-e "$d2/main.cf" || die "$::myname: error: $d2/main.cf: $!\n";

my $sort = $::opt_s ? '| sort' : '';

my $sed = q(sed -e 's/[, 	][, 	]*/ /g');

system "postconf -n -c $d1 | $sed $sort | cat > $t1";
system "postconf -n -c $d2 | $sed $sort | cat > $t2";
my @options = ();
$::opt_b && push(@options, '-b');
$::opt_u && push(@options, '-u');
$::opt_c && push(@options, '-c');
system "diff @options $t1 $t2";

sub usage_error {
  my($msg) = @_;
  if ($msg) {
    die "$msg\n";
  } else {
    die "$::usage\n";
  }
}

sub givehelp {
   ## require 'local/page.pl';
   ## &page(<<EOF);
   print <<EOF;
$::usage

Given two directory names where two instances of Postfix reside, prints
a concise list of difference between the configurations as obtained by
invoking 'postconf'.  This program can also be used to compare Postfix
configurations before and after major changes, by saving the initial
configuration into a temporary directory before the changes are
implemented.

The algorithm is very simple:  Invoke postconf on the two specified
directories, squeeze out blanks, optionally sort, save into temp files,
then invoke the 'diff' command on the temp files.

The postconf command must be found in the user's execution path.

  -v		Be verbose.
  -t		Trace only -- show what would be done but don't do it.
  -x		Enable debugging -- for program maintainers.
  -X		Enable more debugging -- for program maintainers.

  -u		Passed on to diff.
  -c		Passed on to diff.
  -b		Passed on to diff.
  -s		Sort before diff (is no-op since Postfix already sorts)

$::RCSHEADER
EOF
}