#! /usr/bin/perl
# fixscript will replace this line with require innshellvars.pl

#  $Id: cnfsstat.in,v 1.20 2004/01/12 06:19:19 rra Exp $
# 
#  Copyright Andreas Lamrecht 1998
#  <Andreas.Lamprect@siemens.at>
#
#  Modified by Kjetil T. Homme 1998, 2000
#  <kjetilho@ifi.uio.no>
#
#  Modified by Robert R. Collier 1998
#  <rob@lspace.org>
# 
#  bigint support added by Duane Currie (sandman@hub.org) 1998

use vars qw($opt_l $opt_h $opt_a $opt_s);
use Getopt::Long;
use Math::BigInt;
use Math::BigFloat;
use English;

my($conffile) = "$inn::pathetc/cycbuff.conf";
my($storageconf) = "$inn::pathetc/storage.conf";

sub usage {
    print <<_end_;
Summary tool for CNFS

Usage:
	$0 [-c CLASS] [-l [seconds]]

	If called without args, does a one-time status of all CNFS buffers
	-a:          print the age of the oldest article in the cycbuff
	-c <CLASS>:  prints out status of CNFS buffers in class CLASS
	-l seconds:  loops like vmstat, default seconds = 600
	-s:          logs through syslog
	-h:          This information
	-m <BUFFER>: prints out information suitable for mrtg
	-p:	     prints out an mrtg config file 
	-P:          write PID into $inn::pathrun/cnfsstat.pid
_end_
    exit(1);
}

my(@line, %class, %buff, %stor, $c, @buffers);

my($gr, $cl, $min, $max, @storsort, $oclass, $header_printed);

Getopt::Long::config('no_ignore_case');
GetOptions("-a", "-c=s", \$oclass, "-h", "-l:i", "-s", "-m=s", \$obuffer,
           "-p", "-P");

&usage if $opt_h;

if ($opt_s) {
    $use_syslog = 0;
    ## Comment out this eval line if you don't want to try to syslog
    eval { require Sys::Syslog; import Sys::Syslog; $use_syslog = 1 };
    if ($use_syslog) {
	if (defined &Sys::Syslog::setlogsock && $] >= 5.00403) {
	    # we really need a common module to work all this junk out
	    if ($OSNAME eq "dec_osf") {
		sub Sys::Syslog::_PATH_LOG { "/dev/log" }
            }
            Sys::Syslog::setlogsock('unix') 
                if $OSNAME =~ /linux|freebsd|dec_osf|darwin/;
        }
	openlog ('cnfsstat', 'pid', $inn::syslog_facility);
    } else {
	print STDERR "Syslog is not available.  -s option is ignored.\n";
    }
}

if ($opt_P) {
    open(FILE, ">$inn::pathrun/cnfsstat.pid") && do {
	print FILE "$$\n";
	close FILE;
    };
}

my($sleeptime) = (defined($opt_l) && $opt_l > 0) ? $opt_l : 600;

unless (&read_cycbuffconf) {
    print STDERR "Cannot open CycBuff Conffile $conffile ...\n";
    exit (1);
}

unless (&read_storageconf) {
    print STDERR "No valid $storageconf.\n";
    exit (1);
}


&mrtg($obuffer) if $obuffer;
&mrtg_config if $opt_p;

#foreach $c (keys(%class)) {
#  print "Class: $c, definition: $class{$c}\n";
#}
#foreach $c (keys(%buff)) {
#  print "Buff: $c, definition: $buff{$c}\n";
#}
# exit(0);

START:

undef($logline);
if ($oclass) {
    if ($class{$oclass}) {
	if (!$header_printed) {
	    ($gr, $cl, $min, $max) = split(/:/, $stor{$oclass});
	    if ($use_syslog) {
		if ($min || $max) {
		    $logline = sprintf("Class %s for groups matching \"%s\" article size min/max: %d/%d", $oclass, $gr, $min, $max); 
		} else {
		    $logline = sprintf("Class %s for groups matching \"%s\"", $oclass, $gr); 
		}
	    } else {
		print STDOUT "Class $oclass";
		print STDOUT " for groups matching \"$gr\"";
		if ($min || $max) {
		    print STDOUT ", article size min/max: $min/$max";
		}
		print STDOUT "\n";
	    }
	    $header_printed = 1;
	}
	
	@buffers = split(/,/, $class{$oclass});
	if (! @buffers) {
	    print STDERR "No buffers in Class $main::ARGV[0] ...\n";
	    next;
	}
	
	foreach $b (@buffers) {
	    if (! $buff{$b} ) {
		print STDERR "No buffer definition for buffer $b ...\n";
		next;
	    }
	    &print_cycbuff_head($buff{$b});
	}
    } else {
	print STDERR "Class $ARGV[1] not found ...\n";
    }
} else { # Print all Classes
    
    foreach $c (@storsort) {
	($gr, $cl, $min, $max) = split(/:/, $stor{$c});
	if ($use_syslog) {
	    if ($min || $max) {
		$logline = sprintf("Class %s for groups matching \"%s\" article size min/max: %d/%d", $c, $gr, $min, $max); 
	    } else {
		$logline = sprintf("Class %s for groups matching \"%s\"", $c, $gr); 
	    }
	} else {
	    print STDOUT "Class $c ";
	    print STDOUT " for groups matching \"$gr\"";
	    if($min || $max) {
		print STDOUT ", article size min/max: $min/$max";
	    }
	    print STDOUT "\n";
	}
	@buffers = split(/,/, $class{$c});
	if(! @buffers) {
	    print STDERR "No buffers in Class $c ...\n";
	    next;
	}
	
	foreach $b (@buffers) {
	    if(! $buff{$b} ) {
		print STDERR "No buffer definition for buffer $b ...\n";
		next;
	    }
	    &print_cycbuff_head($buff{$b});
	}
	if ($use_syslog == 0) {
	    print STDOUT "\n";
	}
    }
}

if(defined($opt_l)) {
    sleep($sleeptime);
    if ($use_syslog == 0) {
	print STDOUT "$sleeptime seconds later:\n";
    }
    goto START;
}

sub read_cycbuffconf {
    return 0 unless open (CONFFILE, $conffile);

    while(<CONFFILE>) {
	$_ =~ s/^\s*(.*?)\s*$/$1/;
	# Here we handle continuation lines
	while (m/\\$/) {
	    $contline = <CONFFILE>;
	    $contline =~ s/^\s*(.*?)\s*$/$1/;
	    chop;
	    $_ .= $contline;
	}
	# \x23 below is #.  Emacs perl-mode gets confused by the "comment"
	next if($_ =~ /^\s*$/ || $_ =~ /^\x23/);
	next if($_ =~ /^cycbuffupdate:/ || $_ =~ /^refreshinterval:/);
	
	if($_ =~ /^metacycbuff:/) {
	    @line = split(/:/, $_);
	    if($class{$line[1]}) {
		print STDERR "Class $line[1] more than one time in CycBuff Conffile $conffile ...\n";
		return 0;
	    }

	    $class{$line[1]} = $line[2];
	    next;
	}

	if ($_ =~ /^cycbuff/) {
	    @line = split(/:/, $_);
	    if($buff{$line[1]}) {
		print STDERR "Buff $line[1] more than one time in CycBuff Conffile $conffile ...\n";
		return 1;
	    }
	    $buff{$line[1]} = $line[2];
	    next;
	}

	print STDERR "Unknown config line \"$_\" in CycBuff Conffile $conffile ...\n";
    }
    close(CONFFILE);
    return 1;
}

sub read_storageconf {
    my $line = 0;
    return 0 unless open (STOR, $storageconf);

    while (<STOR>) {
	++$line;
	next if /^\s*#/;

	# defaults
	%key = ("NEWSGROUPS" => "*",
		"SIZE" => "0,0");
		
	if (/method\s+cnfs\s+\{/) {
	    while (<STOR>) {
		++$line;
		next if /^\s*#/;
		last if /\}/;
		if (/(\w+):\s+(\S+)/i) {
		    $key{uc($1)} = $2;
		}
	    }
	    unless (defined $key{'CLASS'} && defined $key{'OPTIONS'}) {
		print STDERR "storage.conf:$line: ".
			"Missing 'class' or 'options'\n";
		return 0;
	    }

	    $key{'SIZE'} .= ",0" unless $key{'SIZE'} =~ /,/;
	    $key{'SIZE'} =~ s/,/:/;
	    
	    if (!defined $stor{$key{'OPTIONS'}}) {
		$stor{$key{'OPTIONS'}} = "$key{'NEWSGROUPS'}:$key{'CLASS'}:" .
			"$key{'SIZE'}:$key{'OPTIONS'}";
		push(@storsort, $key{'OPTIONS'});
	    }
	}
    }
    return 1;
}

sub print_cycbuff_head {
    my ($buffpath) = $_[0];
    my ($name, $len, $free, $update, $cyclenum, $oldart) =
	    &get_cycbuff_info($buffpath);
    
    if ($use_syslog) {
	($name) = split(/\s/, $name);
	$name =~ s/\0//g;
	syslog ('notice', '%s Buffer %s, len: %d  Mbytes, used: %.2f Mbytes (%4.1f%%) %3d cycles',
		$logline, $name, $len / (1024 * 1024), $free / (1024 * 1024),
		100 * $free/$len, $cyclenum);
	return 0;
    }

    $name =~ s/\0//g;
    print " Buffer $name, size: ", &human_readable($len, 4);
    print ", position: ", &human_readable($free, 4);
    printf("  %.2f cycles\n", $cyclenum + $free/$len);
    my ($when, $ago) = &make_time($update);
    print "  Newest: $when, $ago ago\n";

    if ($opt_a) {
	my ($when, $ago) = &make_time($oldart);
	print "  Oldest: $when, $ago ago\n";
    }
}

sub make_time {
    my ($t) = @_;
    my (@ret);

    my ($sec,$min,$hour,$mday,$mon,$year) =
	    (localtime($t))[0..5];
    push (@ret, sprintf("%04d-%02d-%02d %2d:%02d:%02d",
			$year + 1900, $mon + 1, $mday, $hour, $min, $sec));
    $t = time - $t;

    $mday = int($t/86400); $t = $t % 86400;
    $hour = int($t/3600);  $t = $t % 3600;
    $min  = int($t/60);    $t = $t % 60;

    push (@ret, sprintf("%4d days, %2d:%02d:%02d",
			$mday, $hour, $min, $t));
    return @ret;
}

sub human_readable {
    my ($val, $digits) = @_;
    $val =~ s/\+//;

    my @name = ("kBytes", "MBytes", "GBytes", "TBytes");
    my $base = 1024;
    my $factor = 1024;

    my $unit = -1;
    my $oldscaled = Math::BigFloat->new ($val) / $base;
    my $scaled = $oldscaled;
    while ( ( int($scaled) > 0 ) && ( $unit < $#name ) ) {
	$oldscaled = $scaled;
	$scaled /= $factor;
	$unit++;
    }
    $scaled = $oldscaled;
    my $predigits = length (int($scaled));
    my $postdigits = $digits - $predigits - 1;
    $postdigits = 0 if $postdigits < 0;
    ++$digits;

    return sprintf ("%${digits}.${postdigits}f %s", $scaled, $name[$unit]);
}

sub mrtg {
	my $buffer = shift;
	# print "Buffer = $buff{$buffer}\n";
	@info = &get_cycbuff_info($buff{$buffer});
	print "$info[1]\n";
	print "$info[2]\n";
	print "$info[4]\n";
	print "$info[0]\n";
	exit(0);
}

sub mrtg_config {
	print "Sub MRTG-CONFIG\n";
	foreach $class (sort(keys(%class))) {
		print "##\n## Class  : $class\n## Wildmat: $stor{$class}\n##\n\n";
		foreach $buffer (split /\,/,$class{$class}) {
			&mrtg_buffer($class,$buffer);
		}
	}
	exit(0);
}

sub mrtg_buffer {
	my ($class,$buffer) = @_;
	#my ($name, $num, $buff, $size) = @_;
        $tag = 'cnfs-' . $buffer;

        print 'Target[', $tag, ']: `', "$inn::pathbin/cnfsstat -m ", $buffer, '`', "\n";  
        print 'MaxBytes[', $tag, ']: ', (&get_cycbuff_info($buff{$buffer}))[1], "\n";
        print 'Title[', $tag, ']: ', "${buffer} Usage\n";
        print 'Options[', $tag, ']: growright gauge', "\n";
        print 'YLegend[', $tag, ']: ', "${buffer}\n";
        print 'ShortLegend[', $tag, ']: MB', "\n";
        print 'PageTop[', $tag, ']: ', "<H1>Usage of ${buffer}</H1>\n";
	print "<BR><TT>$stor{$class}</TT>\n";
        print "\n";
        1;
}

sub bigsysseek {
    my($handle, $offset) = @_;

    # $offset may be a bigint; and have a value that doesn't fit in a signed long.
    # Even with largefiles enabled, perl will still truncate the argument to lseek64
    # to 32 bits.  So we seek multiple times, <2G at a time.

    if($offset > 2147483647) {
	# Since perl truncates the return value of lseek64 to 32 bits, it might
	# see a successful return value as negative, and return FALSE (undef).
	# So we must ignore the return value of sysseek and assume that it worked.

	seek($handle, 0, 0);
	while($offset > 2000000000) {
	    sysseek($handle, 2000000000, 1) || return 0;
	    $offset -= 2000000000;
	}
	sysseek($handle, $offset, 1) || return 0;
	return 1;
    } else {
	return sysseek($handle, $offset, 0);
    }
}

sub check_read_return {
  my $result = shift;
  die "read: $!\n" unless defined($result);
  die "read reached eof\n" unless $result;
  return $result;
}

sub get_cycbuff_info {
    my($buffpath) = $_[0];
    
    my($CNFSMASIZ)=8;
    my($CNFSNASIZ)=16;
    my($CNFSPASIZ)=64;
    my($CNFSLASIZ)=16;
    my($headerlength) = $CNFSMASIZ + $CNFSNASIZ + $CNFSPASIZ + (4 * $CNFSLASIZ);
    
    my($buff, @entries, $e);
    my($magic, $name, $path, $lena, $freea, $updatea, $cyclenuma);
    
    if(! open(BUFF, "< $buffpath") ) {
	print STDERR "Cannot open Cycbuff $buffpath ...\n";
	exit(1);
    }
    
    $buff = "";
    if(! read(BUFF, $buff, $headerlength) ) {
	print STDERR "Cannot read $headerlength bytes from file $buffpath...\n";
	exit(1);
    }
    
    ($magic, $name, $path, $lena, $freea, $updatea, $cyclenuma) =
	    unpack("a8 a16 a64 a16 a16 a16 a16", $buff);
    
    if(!$magic) {
	print STDERR "Error while unpacking header ...\n";
	exit(1);
    }
    
    my($len) = bhex($lena);
    my($free) = bhex($freea);
    my($update) = hex($updatea);
    my($cyclenum) = hex($cyclenuma) - 1;
    
    if ($opt_a) {

	my $pagesize = 16384;
	my $minartoffset = int($len / (512 * 8)) + 512;
	# Align upwards:
	$minartoffset = ($minartoffset + $pagesize) & ~($pagesize - 1);
	
	if ($cyclenum == 0 && $free == $minartoffset) {
	    # The cycbuff has no articles yet.
	    goto done;
	}

	# Don't loop endlessly, set rough upper bound
	my $sentinel = $cyclenum == 0 ? $free : $len;
	my $offset = $cyclenum == 0 ? $minartoffset : $free + $pagesize;

	bigsysseek (BUFF, $offset) || die "sysseek: $!\n";
	check_read_return (sysread (BUFF, $buff, $pagesize));
	do {
	    check_read_return (sysread (BUFF, $chunk, $pagesize));
	    
	    $buff .= $chunk;
	    while ($buff =~ /^message-id:\s+(<.*?>)/mi) {
		$buff = $POSTMATCH;
		$oldart = &lookup_age ($1);
		next unless $oldart;
		
		# Is the article newer than the last update?
		if ($oldart >= $update) {
		    $update = $oldart;
		} elsif ($oldart < $update - 60) {
		    goto done;
		}
	    }
	    # Just in case we chopped Message-ID in two, use the end
	    # at the front in next iteration.
	    $buff = substr ($buff, -512);

	} while ($sentinel -= $pagesize > 0);
    }

done:    
    close(BUFF);
    return($name,$len,$free,$update,$cyclenum,$oldart);
}

sub lookup_age {
    my ($msgid) = @_;

    my $history = &safe_run("grephistory", "-l", $msgid);
    if ($history =~ /\t(\d+)~/) {
	return $1;
    }
    print "  (Missing $msgid)\n";
    return 0;
}

sub safe_run {
    my $output = "";

    my $pid = open(KID_TO_READ, "-|");
    die "fork: $!\n" unless defined $pid;
    if ($pid) {
	while (<KID_TO_READ>) {
	    $output .= $_;
	}
	close(KID_TO_READ);
    } else {
	exec(@_) || die "can't exec $_[0]: $!";
	# NOTREACHED
    }
    return $output;
}

# Hex to bigint conversion routine
# bhex(HEXSTRING) returns BIGINT  (with leading + chopped off)
#
# In most languages, unlimited size integers are done using string math
# libraries usually called bigint.  (Java, Perl, etc...)

# Bigint's are really just strings.

sub bhex {
    my $hexValue = shift;
    $hexValue =~ s/^0x//;
    
    my $integerValue = new Math::BigInt '0';
    for (my $i = 0; $i < length($hexValue); $i += 2) {
        # Could be more efficient going at larger increments, but byte
        # by byte is safer for the case of 9 byte values, 11 bytes, etc.. 
 
        my $byte = substr($hexValue, $i, 2);
        my $byteIntValue = hex($byte);

        $integerValue = $integerValue * "256";
        $integerValue = $integerValue + "$byteIntValue";
    }

    $integerValue =~ s/^\+//;
    return $integerValue;
}
