# HG changeset patch
# User Eris Caffee <discordia@eldalin.com>
# Date 1310990476 18000
# Node ID fa7be81d0e336a46ab2c3c7abf42d438c4d3a481
# Parent  706c20861682d2f1885cc435fd9919fc9d83e914
Many changes: Made generic, not cPanel specific.  Reads /etc/passwd using fast I/O to check for existing users. Converted to standalone command line utility with several options: -h -d -t -m

diff -r 706c20861682 -r fa7be81d0e33 make-username.pl
--- a/make-username.pl	Sat Jul 16 13:23:21 2011 -0500
+++ b/make-username.pl	Mon Jul 18 07:01:16 2011 -0500
@@ -1,72 +1,123 @@
 #!/usr/bin/env perl
 
+################################################################################
+#
+# Creates a new unused username for use on a cPanel server.
+#
+################################################################################
+
+use 5.010;
+
 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 = "";
+    my $t1 = time;
+    $user = make_username($base, $pwdfile);
+    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);
+    $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);
+    $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);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "short";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "123digits";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "this *&% is not allowed &^$%&^m";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "this-is-a-domain.com";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "123digits";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = '&$%#&$*&$%*&';
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "this-is-a-domain.com";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "testqwer";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = '&$%#&$*&$%*&';
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "testabc";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-# 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";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "testqwer";
-$user = make_username($base);
-printf("%30s %s\n", $base, $user);
+    $base = "test";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
 
-$base = "testabc";
-$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";
+    $t1 = time;
+    $user = make_username($base, $pwdfile);
+    $t2 = time;
+    defined $user and printf("%30s %-".$maxlen."s in %ds\n", $base, $user, $t2 - $t1);
+}
 
 sub make_username {
     # Arguments:
@@ -81,12 +132,19 @@
     # 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 +156,91 @@
     # 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", $base);
+
+
+    # ----- Times: 88s, 89s, 85s -----
+    # open(F,$pwdfile);
+    # my @passwd=<F>;
+    # close F;
+    # while ((grep {/^${newuser}:/ } @passwd) && ($i < 10000000) ) {
+
+    # ----- Times: 67s, 67s, 67s -----
+    # while ( (! system('grep -qsP "^'.$newuser.':" '.$pwdfile)) && ($i < 10000000) ) { 
+
+    # ----- with user_exists1() Times: 47s, 50s, 50s -----
+    # ----- with user_exists() using sysread Times: 4s, 4s, 4s -----
+    while ( (user_exists($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++;
+	$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 $retval;
+}
+
+sub user_exists1 {
+    my ($user, $pwdfile) = @_;
+    my $retval = 0;
+    open my $handle, "<", $pwdfile;
+    while (<$handle>) {
+	if ($_ =~ /^${user}:/) {
+	    $retval = 1;
+	    last;
+	}
+    }
+    close $handle;
+    return $retval;
+}
+
+################################################################################
+sub usage {
+    printf( 
+"Usage: ".basename($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.
+");
+}
diff -r 706c20861682 -r fa7be81d0e33 passwd-huge.gz
Binary file passwd-huge.gz has changed
diff -r 706c20861682 -r fa7be81d0e33 passwd.gz
Binary file passwd.gz has changed