#!/usr/local/bin/perl
# counter.xbm - Perl script to keep count of users of a
# home page.
#
# Credits:
# Original C code: Frans van Hoesel (hoesel@chem.rug.nl)
# Original port to Perl: Dan Rich (drich@corp.sgi.com)
# Modifications for cgi: Michael Nelson (m.l.nelson@larc.nasa.gov)
# Modifications for NSF: Mike Morse (mmorse@nsf.gov)
# Modified from NSF version: Spencer Thomas (spencer.thomas@med.umich.edu)
# Modified for flexible use: Stefan Powell (spowell@netaccess.on.ca)
#
# Note: This script should be renamed to counter.xbm
#
push(@INC,'/usr/local/etc/httpd/cgi-bin');
require 'cgi-lib.pl';
select STDOUT;
$|=1;
# Suck stuff from httpd
&ReadParse;
&initialize;
&incrementCount;
if ($ENV{PATH_INFO} && $ENV{PATH_INFO} =~ /.*\/text(\/.*)?/) {
&writeTextCounter;
} else {
&generateBitmap;
&writeBitmap;
}
exit(0);
sub writeTextCounter {
print ("Content-type: text/html\n\n");
print ("Visitor counter\n");
print ("You are visitor number $totalReads\n");
}
sub writeBitmap {
print ("Content-type: image/x-xbitmap\n\n");
if ($isHigh) {
printf ("#define count_width %d\n#define count_height 16\n",
$len*8);
}
else {
printf ("#define count_width %d\n#define count_height 10\n",
$len*8);
}
printf STDOUT "static char count_bits[] = {\n";
for($i = 0; $i < ($#bytes + 1); $i++) {
print("0x$bytes[$i]");
if ($i != $#bytes) {
print(",");
if (($i+1) % 7 == 0) {
print("\n");
}
}
}
print("};\n");
}
# generateBitmap() - $count contains number to display
# $minLen contains minimum number of digits to display
# $isHigh is one for 16 bit high numbers (else 10)
# $isInverse is one for reverse video (white on black);
sub generateBitmap {
$count = $totalReads;
@bytes = ();
$len = length($count) > $minLen ? length($count) : $minLen;
$formattedCount = sprintf("%0${len}d",$count);
if ($isHigh) {
for ($i = 0; $i < $len*3; $i++ ) {
if ($isInverse) {
push(@bytes,"ff"); # add three blank rows to each digit
}
else {
push(@bytes,"00");
}
}
}
for ($y=0; $y < 10; $y++) {
for ($x=0; $x < $len; $x++) {
$digit = substr($formattedCount,$x,1);
if ($isInverse) { # $inv = 1 for inverted text
$byte = substr(@invdigits[$digit],$y*3,2);
}
else {
$byte = substr(@digits[$digit],$y*3,2);
}
push(@bytes,$byte);
}
}
if ($isHigh) {
for ($i = 0; $i < $len*3; $i++ ) {
if ($isInverse) {
push(@bytes,"ff"); # add three blank rows to each digit
}
else {
push(@bytes,"00");
}
}
}
}
sub initialize {
$minLen = 7; # minimum number of digits in bigmap
$isHigh = 1; # if 1, digits are 16 pixels high, to
# allow room for border
$isInverse = 1; # If 1, digits are white on black
$counterdir = "counters/";
$remote_host = $ENV{'REMOTE_HOST'};
if ($#in < 0) {
$scriptURL = "http://" . $ENV{'SERVER_NAME'} . ":" . $ENV{'SERVER_PORT'} . $ENV{'SCRIPT_NAME'};
print ("Content-type: text/html\n\n");
print ("Visitor counter\n");
print ("counter.xbm
To put a visitor counter like this \n");
print ("![](\"$scriptURL?unique_id\")
\n");
print ("on your web page, put an image tag in your HTML document like:
\n");
print ("<IMG SRC=\"$scriptURL?unique_id\">
\n");
print ("where \"unique_id\" is a unique identifier for your counter.\n");
print ("When creating a new counter you can set the starting value by adding a count parameter to the URL. So if the counter \"qwerty\" didn't exist, accessing the URL
\n");
print ("$scriptURL?qwerty&COUNT=1234
\n");
print ("will create a new counter called \"qwerty\" with its counter set to 1234.
The counter can only be set when creating a new counter.\n");
print ("
\n");
exit;
}
else {
$countername = $in[0];
$countername =~ s/\W//g;
$counterFile = $counterdir . $countername;
if (!( -f $counterFile )) {
$start = $in{'COUNT'} -1;
open(CNTRFILE,">$counterFile");
print CNTRFILE "$start\n";
close(CNTRFILE);
}
}
$lockWait = 5; # number of seconds to wait for lock
# bitmap for each digit
# Each digit is 8 pixels wide, 10 high
# @invdigits are white on black, @digits black on white
@invdigits = ("c3 99 99 99 99 99 99 99 99 c3", # 0
"cf c7 cf cf cf cf cf cf cf c7", # 1
"c3 99 9f 9f cf e7 f3 f9 f9 81", # 2
"c3 99 9f 9f c7 9f 9f 9f 99 c3", # 3
"cf cf c7 c7 cb cb cd 81 cf 87", # 4
"81 f9 f9 f9 c1 9f 9f 9f 99 c3", # 5
"c7 f3 f9 f9 c1 99 99 99 99 c3", # 6
"81 99 9f 9f cf cf e7 e7 f3 f3", # 7
"c3 99 99 99 c3 99 99 99 99 c3", # 8
"c3 99 99 99 99 83 9f 9f cf e3"); # 9
@digits = ("3c 66 66 66 66 66 66 66 66 3c", # 0
"30 38 30 30 30 30 30 30 30 30", # 1
"3c 66 60 60 30 18 0c 06 06 7e", # 2
"3c 66 60 60 38 60 60 60 66 3c", # 3
"30 30 38 38 34 34 32 7e 30 78", # 4
"7e 06 06 06 3e 60 60 60 66 3c", # 5
"38 0c 06 06 3e 66 66 66 66 3c", # 6
"7e 66 60 60 30 30 18 18 0c 0c", # 7
"3c 66 66 66 3c 66 66 66 66 3c", # 8
"3c 66 66 66 66 7c 60 60 30 1c"); # 9
}
sub incrementCount {
if (&lockFile == 1) {
$count = "0";
return;
}
&incrementTotalReads;
&unlockFile;
}
sub unlockFile {
unlink("$counterFile.lock");
}
sub lockFile {
$lockCount = 0;
while (-f "$counterFile.lock") {
if ($lockCount > $lockWait) {
$count = 0;
return 1; # forget it (would be nice to log though)
}
sleep 1;
$lockCount++;
}
open(LOCK,">$counterFile.lock") || die("Can't open $counterFile.lock: $!\n");
return 0;
}
sub incrementTotalReads {
if (-e $counterFile) {
open(COUNT,"$counterFile") || die("Can't open $counterFile: $!\n");
}
$totalReads = ;
chop $totalReads;
close(COUNT);
$totalReads++ if $remote_host ne "kite.netcom.com";
open(COUNT,">$counterFile") || die "$0: can\'t open $counterFile: $!\n";
print (COUNT "$totalReads\n");
close(COUNT);
}