#!/usr/bin/perl

use warnings;
use strict;

my (%foos, %bars);
my %targethash =(
  foo  => \%foos,
  bar  => \%bars,
   );

while( my $line = <DATA> ) {
  chomp $line;
   my ($name, $key, $val ) = $line =~ /^(\w+) ([^:]*):([^:]*)$/ ;
   if (!  $name ){
      warn qq( "$line" is the wrong format.\n );
   }elsif (my $target = $targethash{$name} ){
     $target->{$key} = $val;
  } else {
    warn "Line: $. has Invalid name '$name'\n";   
  }
}

__DATA__
foo key1:val1
bar key2:val2
foo key3:val3
qux key6:val6
bar key4:val4
3 bad:val
4bad:syntax