# HG changeset patch
# User Eris Caffee <discordia@eldalin.com>
# Date 1310991192 18000
# Node ID 742a3d2c99d64face2f7f7668cd6af9c681cae09
# Parent  706c20861682d2f1885cc435fd9919fc9d83e914
Removed commented code and timing notes left from I/O testing.

diff -r 706c20861682 -r 742a3d2c99d6 make-username.pl
--- a/make-username.pl	Sat Jul 16 13:23:21 2011 -0500
+++ b/make-username.pl	Mon Jul 18 07:13:12 2011 -0500
@@ -2,71 +2,90 @@
 
 use warnings;
 use strict;
+use English;
+use File::Basename;
 
-my $base;
-my $user ;
+my $base ="";
+my $user;
+my $debug = 0;
+my $maxlen = 8;
+my $test = 0;
 
-$base = "";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+foreach my $arg (@ARGV) {
+    if ("-d" eq $arg) {
+	$debug = 1;
+    } elsif ($arg =~ /^-m/) {
+	$arg =~ s/^..//;
+	if ($arg =~ /^(\d+)$/) {
+	    $maxlen = $1;
+	    $debug and print "Setting maxlen to $maxlen\n";
+	} else {
+	    printf(STDERR "Invalid username length specified: $arg\n");
+	}
+    } elsif ($arg eq "-h") {
+	usage();
+	exit 0;
+    } elsif ($arg eq "-t") {
+	$test = 1;
+    } else {
+	$base = $arg;
+    }
+}
 
-$base = "eightchr";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+if (! $test) {
+    $user = make_username($base);
+    defined $user and printf("%s\n", $user);
+    exit 0;
+} else {
+    my $pwdfile = "passwd";
+    $base = "";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
+    
+    $base = "eightchr";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
+    
+    $base = "short";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
+    
+    $base = "this *&% is not allowed &^$%&^m";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "short";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "123digits";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "this *&% is not allowed &^$%&^m";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "this-is-a-domain.com";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "123digits";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = '&$%#&$*&$%*&';
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "this-is-a-domain.com";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "testqwer";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = '&$%#&$*&$%*&';
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "testabc";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-# For the next test, run this first in the shell as root (not on a production system, obviously!):
-#
-# [ ! -d /var/cpanel/users ] && mkdir -p /var/cpanel/users
-# touch /var/cpanel/users/testqwer
-# touch /var/cpanel/users/testabc
-# i=1 ; while [ $i -lt 10 ] ; do touch /var/cpanel/users/testabc${i} ; let i=$i+1 ; done
-# touch /var/cpanel/users/testzx
-# i=1 ; while [ $i -lt 100 ] ; do touch /var/cpanel/users/testzx${i} ; let i=$i+1 ; done
-# touch /var/cpanel/users/test
-# i=1 ; while [ $i -lt 100 ] ; do touch /var/cpanel/users/test${i} ; let i=$i+1 ; done
-# touch /var/cpanel/users/t
-# i=1 ; while [ $i -lt 10346 ] ; do touch /var/cpanel/users/t${i} ; let i=$i+1 ; done
+    $base = "testzx";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "testqwer";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "test";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
 
-$base = "testabc";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
-
-$base = "testzx";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
-
-$base = "test";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
-
-$base = "t";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
-
+    $base = "t";
+    $user = make_username($base, $pwdfile);
+    defined $user and printf("%30s %s\n", $base, $user);
+}
 
 sub make_username {
     # Arguments:
@@ -81,12 +100,19 @@
     # A string containing the new username or undef if no username 
     # could be generated  (unlikely)
 
-    my ($base) = @_;
+    my ($base, $pwdfile) = @_;
 
     if ($base eq "") {
 	$base = "user";
     }
 
+    ! defined $pwdfile and $pwdfile = "/etc/passwd";
+
+    if (! -e $pwdfile) {
+	printf(STDERR "Error: non-existant passwd file specified: $pwdfile\n");
+	return undef;
+    }
+
     # 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]/ ) { 
@@ -98,17 +124,48 @@
     # Print the number into the last portion of the new username.
     # Delete spaces (in case the passed username candidate was short).
     # Churn until we find an unused name.
+    my $tries=0;
     my $i=1;
     my $numstr;
-    my $newuser = sprintf("%.8s", $base);
-    while ( (-e "/var/cpanel/users/$newuser") && ($i < 10000000) ) { 
+    my $newuser = sprintf("%.".$maxlen."s", $base);
+
+    while ( (! system('grep -qsP "^'.$newuser.':" '.$pwdfile)) &&
+	    ($i < 10000000) ) { 
+	$tries = 1;
 	$numstr = sprintf("%d", $i);
-	$newuser = sprintf("%-8s", $base);
+	$newuser = sprintf("%-".$maxlen."s", $base);
 	substr($newuser, -length($numstr), length($numstr), $numstr);
 	$newuser =~ s/ //g;
         $i++;
     }
 
     $i == 10000000 && return undef;
+    $debug and print "final is $newuser in $tries attempts\n";
     return $newuser;
 }
+
+
+################################################################################
+sub usage {
+    printf( 
+"Usage: ".basename($PROGRAM_NAME)." [-h] [-d] [-mM] [-t] [basename]
+
+Generate a new unused username suitable for assigning to a new account.
+
+basename    If specified this will be used as the basis of the new username
+
+            The basename will be stripped of all characters other than letters 
+            and digits, and it will be truncated to no more than the maximum 
+            allowed username length (8 by default, but settable with the 
+            -m option).
+            In the event that a user already exists by the given name a number 
+            will be inserted at the end of the username and sequentially 
+            increased until an available name is found.
+            If basename is not specified, then \"user\" will be used as the base.
+-h          Print these instructions.
+-d          Enable debug messages.
+-mM         Set maximum allowed username length to M (default is 8).
+-t          Perform test code.  You must have a suitable passwd file in the 
+            current directory in order to run this.
+");
+}