# HG changeset patch
# User Eris Caffee <discordia@eldalin.com>
# Date 1310999840 18000
# Node ID 0979af167267f3f8a625222beeae98320f394571
# Parent  742a3d2c99d64face2f7f7668cd6af9c681cae09
Removed commented code and timing notes left from I/O testing.

diff -r 742a3d2c99d6 -r 0979af167267 make-username.pl
--- a/make-username.pl	Mon Jul 18 07:13:12 2011 -0500
+++ b/make-username.pl	Mon Jul 18 09:37:20 2011 -0500
@@ -1,5 +1,28 @@
 #!/usr/bin/env perl
 
+################################################################################
+#
+# Copyright (C) 2011 Sarah Eris Horsley Caffee
+#
+# This is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+################################################################################
+#
+# Returns a new unused username for use on a *nix server.
+#
+################################################################################
+
 use warnings;
 use strict;
 use English;
@@ -39,52 +62,76 @@
 } else {
     my $pwdfile = "passwd";
     $base = "";
+    my $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    my $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
     
     $base = "eightchr";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
     
     $base = "short";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
     
     $base = "this *&% is not allowed &^$%&^m";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "123digits";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "this-is-a-domain.com";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = '&$%#&$*&$%*&';
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "testqwer";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "testabc";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "testzx";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "test";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
     $base = "t";
+    $t1 = time;
     $user = make_username($base, $pwdfile);
-    defined $user and printf("%30s %s\n", $base, $user);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 }
 
 sub make_username {
@@ -113,7 +160,8 @@
 	return undef;
     }
 
-    # Remove non-alpha-numeric characters and make sure the first character is a letter.
+    # Remove non-alpha-numeric characters and make sure the first character 
+    # is a letter.
     $base =~ s/[^A-Za-z0-9]//g;
     if ($base !~ /^[a-z]/ ) { 
         $base = "a".$base;
@@ -129,21 +177,38 @@
     my $numstr;
     my $newuser = sprintf("%.".$maxlen."s", $base);
 
-    while ( (! system('grep -qsP "^'.$newuser.':" '.$pwdfile)) &&
-	    ($i < 10000000) ) { 
+    while ( (user_exists($newuser, $pwdfile)) && ($i < 10000000) ) { 
 	$tries = 1;
 	$numstr = sprintf("%d", $i);
 	$newuser = sprintf("%-".$maxlen."s", $base);
 	substr($newuser, -length($numstr), length($numstr), $numstr);
 	$newuser =~ s/ //g;
         $i++;
+	$debug and printf(STDERR "Checking for $newuser\n");
     }
 
-    $i == 10000000 && return undef;
+    $i == 10000000 and return undef;
     $debug and print "final is $newuser in $tries attempts\n";
     return $newuser;
 }
 
+sub user_exists {
+    my ($user, $pwdfile) = @_;
+
+    my $retval = 0;
+    my $i;
+    my $buffer;
+
+    open my $handle, "<", $pwdfile;
+    while (sysread($handle, $buffer, 65536, 0)) {
+	if ($buffer =~ /(^|\n)${user}:/) {
+	    $retval = 1;
+	    last;
+	}
+    }
+    close $handle;
+    return $retval;
+}
 
 ################################################################################
 sub usage {
diff -r 742a3d2c99d6 -r 0979af167267 passwd-huge.gz
Binary file passwd-huge.gz has changed
diff -r 742a3d2c99d6 -r 0979af167267 passwd.gz
Binary file passwd.gz has changed