#!/usr/bin/perl

=pod

=head1 NAME

B<CHECKRPMS> - automated status report about RPMs on a system

=head1 SYNOPSIS

./CHECKRPMS

or

perl CHECKRPMS

=head1 DESCRIPTION

This file automates the usage of Martin Siegert's "check-rpms"
script.  It runs through a list of possible mirror sites
until it finds one with a reasonably good FTP connection.

=head2 Future directions

Eventually, this script may have a simple argument format
that allows the user to VIEW, DOWNLOAD, or AUTOUPDATE their
computer.  Or, this script may evolve into an interactive
series of steps:  For example, there may be questions like this:

=over 4

=item *

Do you want to (D)ownload or (A)utoupdate the RPMs
in the list above?

=item *

Specify a download location for the RPMs
(default=/tmp/update_my_rpms/)?

=back

Note that there are no current plans to automate a software upgrade of the
kernel.  This step should be performed by a qualified system administrator.

=head1 AUTHOR

Scott Harrison, sharrison@users.sourceforge.net, 2002

=cut

# =================================================== READ IN COMMAND ARGUMENTS
# ---------------------------------------------------- Process download option.
my $download=shift(@ARGV);
if ($download eq '--download')
  {
    if ($< != 0) # Download mode requires 'root'.
      {
        print('**** ERROR **** Download mode needs to be run as root'."\n");
	exit(1); # Exit with error status.
      }
    `rm -Rf /tmp/loncapa_rpm_updates`;
    $download='-v -dl -d /tmp/loncapa_rpm_updates'; # Part of check-rpms args.
  }
else
  {
    $download='';
  }

# =================================================== GENERAL INITIAL VARIABLES
# ---------------- The FTP servers (and their directory paths) to check against
my @serverpaths_to_try=(
   'mirror.pa.msu.edu/linux/redhat/linux/updates/',
   'rufus.w3.org/linux/redhat/linux/updates/',
   'distro.ibiblio.org/pub/linux/distributions/redhat/updates/',
   'limestone.uoregon.edu/redhat/updates/',
   'opnsrc.support.compaq.com/linux/redhat/updates.redhat.com/',
);

# --------------------------------------------------- Determine RedHat version.
my $RHversion = (split /\s/, `cat /etc/redhat-release`)[4]; # - 6.2 or 7.3 or ?

 # ------------------------------------------- Use check-rpms command this way.
my $checkcommand='check-rpms '.$download.' --rpmuser www -ftp';

my $FTPSERVER; # ------------------------- the server portion of the serverpath
my $FTPUPDATES; # ----------------------------- the actual update root location
my @rpms; # ---------------------------------- this will store the list of RPMs
my $goodoutput; # ------------------------------------ good stuff was returned!
my $reallygoodoutput; # ------------------------------- you are 100% up-to-date

# ----------------------------------------- Find the check-rpms script location
if (-e './check-rpms') {
    $commandpre='perl ./';
}
elsif (-e 'loncom/build/check-rpms') {
    $commandpre='perl loncom/build/';
}
else {
    die("**** ERROR **** CANNOT FIND THE check-rpms SCRIPT\n");
}

$checkcommand=$commandpre.$checkcommand;

# =============== Go through all the servers until a decent connection is found
print(<<END);
THIS SCRIPT IS NOW PROBING SEVERAL FTP SERVERS....
PLEASE BE PATIENT, THIS MAY TAKE A FEW MINUTES.
END

SERVERLOOP: foreach my $serverpath (@serverpaths_to_try) {
    $serverpath=~/^(.*?)\//;
    $FTPSERVER=$1;
    print "Trying $FTPSERVER...\n";
    `ping -c 1 $FTPSERVER 2>/dev/null`;
    if ($?==0) {
	print "$FTPSERVER found...\n";
	`ncftpls ftp://$FTPSERVER`;
	if ($?==0) {
	    $FTPUPDATES="$serverpath$RHversion/en/os";
	    print "$checkcommand $FTPUPDATES\n";
	    if ($download) {
		$|=1;
		print `$checkcommand $FTPUPDATES 2>\&1`;
		exit(0);
	    }
	    @rpms=`$checkcommand $FTPUPDATES 2>\&1`;
	    my $rpmtext=join('',@rpms);
	    if ($rpmtext=~/You do not seem to have a/) {
		print "You do not have a 'www' user on your system.\n".
		    "Please add this user and try this command again.\n";
		exit(1);
	    }
	    if ($rpmtext=~/This account is currently not/) { # ---------- uh-oh
		print "...strange error, moving on ($FTPSERVER)\n";
	    }
	    else { # ------------------------------------- the output is "good"
		$goodoutput=$rpmtext;
		unless (@rpms) {
		    $reallygoodoutput=<<END;
**** NOTE **** All RPMS on your system appear to be up to date.
END
		}
		last SERVERLOOP;
	    }
	}
	print "...cannot establish an ftp session with $FTPSERVER\n";
    }
    else {
	print "...cannot find $FTPSERVER on the network\n";
    }
}
if (!$goodoutput) {
    print "**** ERROR **** Cannot find a working ftp server.\n";
    exit(1);
}
elsif ($reallygoodoutput) {
    print $reallygoodoutput;
}
else {
    my $rpmcount=scalar(@rpms);
    print(<<END);
**** WARNING **** You need to update at least $rpmcount RPMS shown in
the list below.  THIS IS IMPORTANT FOR SECURITY.

END
    print $goodoutput;
    print(<<END);

Please visit ftp://$FTPUPDATES
and download the RPMS you need.
For instructions on working with (and upgrading) RPMS, please
visit http://www.rpm.org/max-rpm/.
To automatically download these RPMs to /tmp/loncapa_rpm_updates/,
run the CHECKRPMS command as "./CHECKRPMS --download"
END
}