[LON-CAPA-cvs] cvs: loncom /homework response.pm /lonnet/perl lonnet.pm

[albertel]

albertel		Tue Dec  7 11:19:37 2004 EDT

  Modified files:              
    /loncom/homework	response.pm 
    /loncom/lonnet/perl	lonnet.pm 
  Log:
  - 64bit4 and numval3, numval2 could generate values greater than 2^31-1 in somecases (long symbs being a good one), which would collapse to -1, thus making the symb a source of no random seed data
  
  
  
Index: loncom/homework/response.pm
diff -u loncom/homework/response.pm:1.109 loncom/homework/response.pm:1.110
--- loncom/homework/response.pm:1.109	Mon Nov  8 14:20:13 2004
+++ loncom/homework/response.pm	Tue Dec  7 11:19:37 2004
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # various response type definitons response definition
 #
-# $Id: response.pm,v 1.109 2004/11/08 19:20:13 albertel Exp $
+# $Id: response.pm,v 1.110 2004/12/07 16:19:37 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -124,11 +124,16 @@
 	if (defined($Apache::inputtags::response[-1])) {
 	    $rndmod+=&Apache::lonnet::numval($Apache::inputtags::response[-1]);
 	}
-    } else {
+    } elsif ($rand_alg eq '64bit3') {
 	$rndmod=(&Apache::lonnet::numval2($Apache::inputtags::part) << 10);
 	if (defined($Apache::inputtags::response[-1])) {
 	    $rndmod+=&Apache::lonnet::numval2($Apache::inputtags::response[-1]);
 	}
+    } else {
+	$rndmod=(&Apache::lonnet::numval3($Apache::inputtags::part) << 10);
+	if (defined($Apache::inputtags::response[-1])) {
+	    $rndmod+=&Apache::lonnet::numval3($Apache::inputtags::response[-1]);
+	}
     }
     if ($rndseed =~/([,:])/) {
 	my $char=$1;
Index: loncom/lonnet/perl/lonnet.pm
diff -u loncom/lonnet/perl/lonnet.pm:1.574 loncom/lonnet/perl/lonnet.pm:1.575
--- loncom/lonnet/perl/lonnet.pm:1.574	Mon Dec  6 13:08:39 2004
+++ loncom/lonnet/perl/lonnet.pm	Tue Dec  7 11:19:37 2004
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.574 2004/12/06 18:08:39 banghart Exp $
+# $Id: lonnet.pm,v 1.575 2004/12/07 16:19:37 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -4699,7 +4699,9 @@
     my $symb=&symbread($urlsymb);
     if ($symb) {
 	my ($result,$cached)=&is_cached(\%titlecache,$symb,'title',600);
-	if (defined($cached)) { return $result; }
+	if (defined($cached)) { 
+	    return $result;
+	}
 	my ($map,$resid,$url)=&decode_symb($symb);
 	my $title='';
 	my %bighash;
@@ -4971,8 +4973,25 @@
     return int($total);
 }
 
+sub numval3 {
+    use integer;
+    my $txt=shift;
+    $txt=~tr/A-J/0-9/;
+    $txt=~tr/a-j/0-9/;
+    $txt=~tr/K-T/0-9/;
+    $txt=~tr/k-t/0-9/;
+    $txt=~tr/U-Z/0-5/;
+    $txt=~tr/u-z/0-5/;
+    $txt=~s/\D//g;
+    my @txts=split(/(\d\d\d\d\d\d\d\d\d)/,$txt);
+    my $total;
+    foreach my $val (@txts) { $total+=$val; }
+    if ($_64bit) { $total=(($total<<32)>>32); }
+    return $total;
+}
+
 sub latest_rnd_algorithm_id {
-    return '64bit3';
+    return '64bit4';
 }
 
 sub get_rand_alg {
@@ -5011,7 +5030,13 @@
     if (!$username) { $username=$wusername }
     my $which=&get_rand_alg();
     if (defined(&getCODE())) {
-	return &rndseed_CODE_64bit($symb,$courseid,$domain,$username);
+	if ($which eq '64bit4') {
+	    return &rndseed_CODE_64bit4($symb,$courseid,$domain,$username);
+	} else {
+	    return &rndseed_CODE_64bit($symb,$courseid,$domain,$username);
+	}
+    } elsif ($which eq '64bit4') {
+	return &rndseed_64bit4($symb,$courseid,$domain,$username);
     } elsif ($which eq '64bit3') {
 	return &rndseed_64bit3($symb,$courseid,$domain,$username);
     } elsif ($which eq '64bit2') {
@@ -5108,6 +5133,30 @@
     }
 }
 
+sub rndseed_64bit4 {
+    my ($symb,$courseid,$domain,$username)=@_;
+    {
+	use integer;
+	# strings need to be an even # of cahracters long, it it is odd the
+        # last characters gets thrown away
+	my $symbchck=unpack("%32S*",$symb.' ') << 21;
+	my $symbseed=numval3($symb) << 10;
+	my $namechck=unpack("%32S*",$username.' ');
+	
+	my $nameseed=numval3($username) << 21;
+	my $domainseed=unpack("%32S*",$domain.' ') << 10;
+	my $courseseed=unpack("%32S*",$courseid.' ');
+	
+	my $num1=$symbchck+$symbseed+$namechck;
+	my $num2=$nameseed+$domainseed+$courseseed;
+	#&Apache::lonxml::debug("$symbseed:$nameseed;$domainseed|$courseseed;$namechck:$symbchck");
+	#&Apache::lonxml::debug("rndseed :$num1:$num2:$_64bit");
+	if ($_64bit) { $num1=(($num1<<32)>>32); $num2=(($num2<<32)>>32); }
+	
+	return "$num1:$num2";
+    }
+}
+
 sub rndseed_CODE_64bit {
     my ($symb,$courseid,$domain,$username)=@_;
     {
@@ -5127,6 +5176,25 @@
     }
 }
 
+sub rndseed_CODE_64bit4 {
+    my ($symb,$courseid,$domain,$username)=@_;
+    {
+	use integer;
+	my $symbchck=unpack("%32S*",$symb.' ') << 16;
+	my $symbseed=numval3($symb);
+	my $CODEchck=unpack("%32S*",&getCODE().' ') << 16;
+	my $CODEseed=numval3(&getCODE());
+	my $courseseed=unpack("%32S*",$courseid.' ');
+	my $num1=$symbseed+$CODEchck;
+	my $num2=$CODEseed+$courseseed+$symbchck;
+	#&Apache::lonxml::debug("$symbseed:$CODEchck|$CODEseed:$courseseed:$symbchck");
+	#&Apache::lonxml::debug("rndseed :$num1:$num2:$symb");
+	if ($_64bit) { $num1=(($num1<<32)>>32); }
+	if ($_64bit) { $num2=(($num2<<32)>>32); }
+	return "$num1:$num2";
+    }
+}
+
 sub setup_random_from_rndseed {
     my ($rndseed)=@_;
     if ($rndseed =~/([,:])/) {