#!/usr/bin/perl

# countlog.cgi -- logs Web page hits and passes control to GIF counter

# the first line of this script may have to be changed
# if your system's Perl interpreter is not located in /usr/bin/perl

# Written by P. Lutus Ashland, Oregon lutusp@arachnoid.com 6/2/96

# This script logs accesses but requires a CGI counter program written by others

# Call the counter like this: You are Visitor Number <IMG src="countlog.cgi?df=Ownername">
# Ownername can have particular web page designators attached to it like this:

# Ownername_mypagename

# This allows you to count pages independently.

# The directory in which countlog.cgi is stored must have world read, write
# and execute access. The file countlog.cgi must have world execute access.

# And believe me when I tell you -- this is just the start of the requirements for
# a successful page counter.

# customization area -- begin

# set $collect_stats = 1 if you want to log the origins of accesses
# in a file named Ownername.log

$collect_stats = 1;

$countname = "counter_dat"; # default counter file name

# $countpath is the path to the counter files used
# by the CGI counter program. Usually not in cgi-bin, so there
# has to be a relative path

$countpath = "../counter/data";

# $countvar is the variable name used by the CGI counter program
# for the counter file

$countvar = "df";

# customization area -- end

@envname = (
  'REMOTE_ADDR',
  'REMOTE_HOST',
  'HTTP_REFERER',
  'HTTP_USER_AGENT',
  'HTTP_ACCEPT',
);

if ($ENV{COMSPEC} ne '') { # most definitely MSDOS, so use those old funky names
  @envname = keys(%ENV);
}

if ($ENV{'QUERY_STRING'} ne '') {
  $buffer = $ENV{'QUERY_STRING'}; # get the file name from counter.cgi?ownername construct
  @pairs = split(/&/,$buffer);
  foreach $pair (@pairs) {
    ($name,$value) = split(/=/,$pair);
    $value =~ tr/+/ /;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg;
    $FORM{$name} = $value;
  }
  $countname = $FORM{$countvar}; # get the name of the counter file
}

# now test to see if this is a valid acess

$qsn = $ENV{'SERVER_NAME'};

$qsn =~ s/www.//ig; # remove possible server-name prefix
$qsn =~ s/.com//ig; # remove server-name suffix

if ($ENV{'HTTP_REFERER'} =~ /$qsn/) { # log only if the root server name appears in the referer path
  
  unless (-e "$countpath/$countname") { # unless this file already exists
    open (COUNT,">$countpath/$countname"); # directory has to have world write permission for this to work
    print COUNT "0\n";
    close COUNT;
  }
  
  $count = 0; # now get and increment the counter to stay synced with the CGI program
  open (COUNT,"$countpath/$countname") || die "Content-type:text/plain\n\nCan't open $countname!\n";
  $count = <COUNT>;
  close COUNT;
  $count++; # so the log count agrees with GIF counter
  
  if ($collect_stats) { # owner want to collect data on logons
    $logname = $countname . ".log";
    
    unless (-e $logname) { # unless this file already exists
      open (LOG,">$logname"); # directory has to have world write permission for this to work
      print LOG "Count\tTime";
      foreach $envlbl (@envname) {
        print LOG "\t$envlbl";
      }
      print LOG "\n";
      close LOG;
    } # done initializing stats file
    
    open (LOG,">>$logname"); # now enter this stat record
    $tim = &readtime;
    print LOG "$count\t$tim";
    foreach $envlbl (@envname) {
      print LOG "\t$ENV{$envlbl}";
    }
    print LOG "\n";
    close LOG;
  } # end of collect_stats block
  
# pass control to CGI counter with all the same variables
  
  print"location:Count.cgi\?$buffer\n\n";
  
} # validity test

exit;

sub readtime {
  local ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday,$isdst) = localtime(time);
  sprintf ("%2.0f/%02.0f/%04.0f %2.0f:%02.0f:%02.0f",$mon+1,$mday,($year > 50)?$year+1900:$year+2000,$hour,$min,$sec); # to the stack
}