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Fix @list[0] nonsense to keep perl from warning me about it.

    1: # The LearningOnline Network with CAPA
    2: # Configuration file reader
    3: #
    4: # $Id: Configuration.pm,v 1.11 2003/07/22 19:21:10 matthew Exp $
    5: #
    6: #
    7: # Copyright Michigan State University Board of Trustees
    8: #
    9: # This file is part of the LearningOnline Network with CAPA (LON-CAPA).
   10: #
   11: # LON-CAPA is free software; you can redistribute it and/or modify
   12: # it under the terms of the GNU General Public License as published by
   13: # the Free Software Foundation; either version 2 of the License, or
   14: # (at your option) any later version.
   15: #
   16: # LON-CAPA is distributed in the hope that it will be useful,
   17: # but WITHOUT ANY WARRANTY; without even the implied warranty of
   18: # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   19: # GNU General Public License for more details.
   20: #
   21: # You should have received a copy of the GNU General Public License
   22: # along with LON-CAPA; if not, write to the Free Software
   23: # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   24: #
   25: # /home/httpd/html/adm/gpl.txt
   26: #
   27: # http://www.lon-capa.org/
   28: #
   29: # YEAR=2002
   30: #
   31: ###
   32: 
   33: # POD documentation is at the end of this short module.
   34: 
   35: package LONCAPA::Configuration;
   36: 
   37: $VERSION = sprintf("%d.%02d", q$Revision: 1.11 $ =~ /(\d+)\.(\d+)/);
   38: 
   39: use strict;
   40: 
   41: my $confdir='/etc/httpd/conf/';
   42: 
   43: # ------------------- Subroutine read_conf: read LON-CAPA server configuration.
   44: # This subroutine reads PerlSetVar values out of specified web server
   45: # configuration files.
   46: sub read_conf
   47:   {
   48:     my (@conf_files)=@_;
   49:     my %perlvar;
   50:     foreach my $filename (@conf_files,'loncapa_apache.conf')
   51:       {
   52: 	open(CONFIG,'<'.$confdir.$filename) or
   53: 	    die("Can't read $confdir$filename");
   54: 	while (my $configline=<CONFIG>)
   55: 	  {
   56: 	    if ($configline =~ /^[^\#]*PerlSetVar/)
   57: 	      {
   58: 		my ($unused,$varname,$varvalue)=split(/\s+/,$configline);
   59: 		chomp($varvalue);
   60: 		$perlvar{$varname}=$varvalue;
   61: 	      }
   62: 	  }
   63: 	close(CONFIG);
   64:       }
   65:     my $perlvarref=\%perlvar;
   66:     return ($perlvarref);
   67:   }
   68: 
   69: #---------------------- Subroutine read_hosts: Read a LON-CAPA hosts.tab
   70: # formatted configuration file.
   71: #
   72: my $RequiredCount = 5;		# Required item count in hosts.tab.
   73: my $DefaultMaxCon = 5;		# Default value for maximum connections.
   74: my $DefaultIdle   = 1000;       # Default connection idle time in seconds.
   75: my $DefaultMinCon = 0;          # Default value for minimum connections.
   76: sub read_hosts {
   77:     my $Filename = shift;
   78:     my %HostsTab;
   79:     
   80:     open(CONFIG,'<'.$Filename) or die("Can't read $Filename");
   81:     while (my $line = <CONFIG>) {
   82: 	if (!($line =~ /^\s*\#/)) {
   83: 	    my @items = split(/:/, $line);
   84: 	    if(scalar @items >= $RequiredCount) {
   85: 		if (scalar @items == $RequiredCount) { # Only required items:
   86: 		    $items[$RequiredCount] = $DefaultMaxCon;
   87: 		}
   88: 		if(scalar @items == $RequiredCount + 1) { # up through maxcon.
   89: 		    $items[$RequiredCount+1] = $DefaultIdle;
   90: 		}
   91: 		if(scalar @items == $RequiredCount + 2) { # up through idle.
   92: 		    $items[$RequiredCount+2] = $DefaultMinCon;
   93: 		}
   94: 		{
   95: 		    my @list = @items; # probably not needed but I'm unsure of 
   96: 		    # about the scope of item so...
   97: 		    $HostsTab{$list[0]} = \@list; 
   98: 		}
   99: 	    }
  100: 	}
  101:     }
  102:     close(CONFIG);
  103:     my $hostref = \%HostsTab;
  104:     return ($hostref);
  105: }
  106: 
  107: 1;
  108: __END__
  109: 
  110: =pod
  111: 
  112: =head1 NAME
  113: 
  114: B<LONCAPA::Configuration> - configuration file reader
  115: 
  116: =head1 SYNOPSIS
  117: 
  118:  use lib '/home/httpd/lib/perl/';
  119:  use LONCAPA::Configuration;
  120: 
  121:  LONCAPA::Configuration::read_conf('loncapa.conf');
  122:  LONCAPA::Configuration::read_hosts(filename);
  123: 
  124: =head1 DESCRIPTION
  125: 
  126: Many different parts of the LON-CAPA software need to reads in the
  127: machine-specific configuration information.  These included scripts
  128: controlling the TCP/IP layer (e.g. F<lonc> and F<lond>), testing scripts
  129: (e.g. test_weblayer.pl and sqltest.pl), and utility scripts
  130: (e.g. clusterstatus.pl and metadata_keywords.pl).
  131: 
  132: The following methods are available:
  133: 
  134: =over 4
  135: 
  136: =item $perlvarref = LONCAPA::Configuration::read_conf( @filename_list );
  137: 
  138: On a typical LON-CAPA server, the filename list argument will consist of
  139: just one element, "loncapa.conf".
  140: 
  141: If there are multiple elements within the filename list, then these
  142: filenames are processed consecutively.
  143: 
  144: A hash reference is returned and consists of those values which
  145: have been initialized from the configuration filenames indicated
  146: in the arguments.
  147: 
  148: If multiple file names define the same hash key, then priority is
  149: given toward the B<last> file name processed.
  150: 
  151: =back
  152: 
  153: =over 4
  154: =item $hostinfo = LONCAPA::Configuration::read_hosts(filename);
  155: 
  156:   The parameter is the name of a file in hosts.tab form.  The file is read and
  157: parsed.  The return value is a reference to a hash.   The hash is indexed by
  158: host and each element of the has is in turn a reference to an anonymous list
  159: containing:
  160: 
  161: =over 4
  162: =item host
  163:    The loncapa hostname of the system. (This may be different than the 
  164:    network hostname, see below).
  165: =item domain
  166:    The loncapa domain in which the host lives.
  167: =item role
  168:     The role of the system, currently allowed values are access for an
  169:     access server and library for a library server.
  170: =item dns
  171:     The DNS hostname of the system. 
  172: =item ip
  173:     The IP address corresponding to the dns hostname of the system.
  174: =item maxconn 
  175:     The maximum number of connections this system should hold to the
  176:     target system's lond.  If the file has no value, a default is supplied
  177:     here by the function.
  178: =item idle
  179:     The number of seconds the oldest idle connection can be idle before it
  180:     should be adaptively dropped.  If the file has no value, a default
  181:     is supplied by the function.
  182: =item mincon
  183:     The minimum number of connections this system should hold to the
  184:     target system's lond.  If the file has no value, a default is supplied by
  185:     the funciton.
  186: 
  187: =back
  188: 
  189: =back
  190: 
  191: 
  192: 
  193: =head1 AUTHORS
  194: 
  195: This library is free software; you can redistribute it and/or
  196: modify it under the same terms as LON-CAPA itself.
  197: 
  198: =cut