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diff --git a/Master/tlpkg/tlperl.straw/lib/Tie/SubstrHash.pm b/Master/tlpkg/tlperl.straw/lib/Tie/SubstrHash.pm
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+package Tie::SubstrHash;
+
+our $VERSION = '1.00';
+
+=head1 NAME
+
+Tie::SubstrHash - Fixed-table-size, fixed-key-length hashing
+
+=head1 SYNOPSIS
+
+ require Tie::SubstrHash;
+
+ tie %myhash, 'Tie::SubstrHash', $key_len, $value_len, $table_size;
+
+=head1 DESCRIPTION
+
+The B<Tie::SubstrHash> package provides a hash-table-like interface to
+an array of determinate size, with constant key size and record size.
+
+Upon tying a new hash to this package, the developer must specify the
+size of the keys that will be used, the size of the value fields that the
+keys will index, and the size of the overall table (in terms of key-value
+pairs, not size in hard memory). I<These values will not change for the
+duration of the tied hash>. The newly-allocated hash table may now have
+data stored and retrieved. Efforts to store more than C<$table_size>
+elements will result in a fatal error, as will efforts to store a value
+not exactly C<$value_len> characters in length, or reference through a
+key not exactly C<$key_len> characters in length. While these constraints
+may seem excessive, the result is a hash table using much less internal
+memory than an equivalent freely-allocated hash table.
+
+=head1 CAVEATS
+
+Because the current implementation uses the table and key sizes for the
+hashing algorithm, there is no means by which to dynamically change the
+value of any of the initialization parameters.
+
+The hash does not support exists().
+
+=cut
+
+use Carp;
+
+sub TIEHASH {
+ my $pack = shift;
+ my ($klen, $vlen, $tsize) = @_;
+ my $rlen = 1 + $klen + $vlen;
+ $tsize = [$tsize,
+ findgteprime($tsize * 1.1)]; # Allow 10% empty.
+ local $self = bless ["\0", $klen, $vlen, $tsize, $rlen, 0, -1];
+ $$self[0] x= $rlen * $tsize->[1];
+ $self;
+}
+
+sub CLEAR {
+ local($self) = @_;
+ $$self[0] = "\0" x ($$self[4] * $$self[3]->[1]);
+ $$self[5] = 0;
+ $$self[6] = -1;
+}
+
+sub FETCH {
+ local($self,$key) = @_;
+ local($klen, $vlen, $tsize, $rlen) = @$self[1..4];
+ &hashkey;
+ for (;;) {
+ $offset = $hash * $rlen;
+ $record = substr($$self[0], $offset, $rlen);
+ if (ord($record) == 0) {
+ return undef;
+ }
+ elsif (ord($record) == 1) {
+ }
+ elsif (substr($record, 1, $klen) eq $key) {
+ return substr($record, 1+$klen, $vlen);
+ }
+ &rehash;
+ }
+}
+
+sub STORE {
+ local($self,$key,$val) = @_;
+ local($klen, $vlen, $tsize, $rlen) = @$self[1..4];
+ croak("Table is full ($tsize->[0] elements)") if $$self[5] > $tsize->[0];
+ croak(qq/Value "$val" is not $vlen characters long/)
+ if length($val) != $vlen;
+ my $writeoffset;
+
+ &hashkey;
+ for (;;) {
+ $offset = $hash * $rlen;
+ $record = substr($$self[0], $offset, $rlen);
+ if (ord($record) == 0) {
+ $record = "\2". $key . $val;
+ die "panic" unless length($record) == $rlen;
+ $writeoffset = $offset unless defined $writeoffset;
+ substr($$self[0], $writeoffset, $rlen) = $record;
+ ++$$self[5];
+ return;
+ }
+ elsif (ord($record) == 1) {
+ $writeoffset = $offset unless defined $writeoffset;
+ }
+ elsif (substr($record, 1, $klen) eq $key) {
+ $record = "\2". $key . $val;
+ die "panic" unless length($record) == $rlen;
+ substr($$self[0], $offset, $rlen) = $record;
+ return;
+ }
+ &rehash;
+ }
+}
+
+sub DELETE {
+ local($self,$key) = @_;
+ local($klen, $vlen, $tsize, $rlen) = @$self[1..4];
+ &hashkey;
+ for (;;) {
+ $offset = $hash * $rlen;
+ $record = substr($$self[0], $offset, $rlen);
+ if (ord($record) == 0) {
+ return undef;
+ }
+ elsif (ord($record) == 1) {
+ }
+ elsif (substr($record, 1, $klen) eq $key) {
+ substr($$self[0], $offset, 1) = "\1";
+ return substr($record, 1+$klen, $vlen);
+ --$$self[5];
+ }
+ &rehash;
+ }
+}
+
+sub FIRSTKEY {
+ local($self) = @_;
+ $$self[6] = -1;
+ &NEXTKEY;
+}
+
+sub NEXTKEY {
+ local($self) = @_;
+ local($klen, $vlen, $tsize, $rlen, $entries, $iterix) = @$self[1..6];
+ for (++$iterix; $iterix < $tsize->[1]; ++$iterix) {
+ next unless substr($$self[0], $iterix * $rlen, 1) eq "\2";
+ $$self[6] = $iterix;
+ return substr($$self[0], $iterix * $rlen + 1, $klen);
+ }
+ $$self[6] = -1;
+ undef;
+}
+
+sub EXISTS {
+ croak "Tie::SubstrHash does not support exists()";
+}
+
+sub hashkey {
+ croak(qq/Key "$key" is not $klen characters long/)
+ if length($key) != $klen;
+ $hash = 2;
+ for (unpack('C*', $key)) {
+ $hash = $hash * 33 + $_;
+ &_hashwrap if $hash >= 1e13;
+ }
+ &_hashwrap if $hash >= $tsize->[1];
+ $hash = 1 unless $hash;
+ $hashbase = $hash;
+}
+
+sub _hashwrap {
+ $hash -= int($hash / $tsize->[1]) * $tsize->[1];
+}
+
+sub rehash {
+ $hash += $hashbase;
+ $hash -= $tsize->[1] if $hash >= $tsize->[1];
+}
+
+# using POSIX::ceil() would be too heavy, and not all platforms have it.
+sub ceil {
+ my $num = shift;
+ $num = int($num + 1) unless $num == int $num;
+ return $num;
+}
+
+# See:
+#
+# http://www-groups.dcs.st-andrews.ac.uk/~history/HistTopics/Prime_numbers.html
+#
+
+sub findgteprime { # find the smallest prime integer greater than or equal to
+ use integer;
+
+ my $num = ceil(shift);
+ return 2 if $num <= 2;
+
+ $num++ unless $num % 2;
+ my $i;
+ my $sqrtnum = int sqrt $num;
+ my $sqrtnumsquared = $sqrtnum * $sqrtnum;
+
+ NUM:
+ for (;; $num += 2) {
+ if ($sqrtnumsquared < $num) {
+ $sqrtnum++;
+ $sqrtnumsquared = $sqrtnum * $sqrtnum;
+ }
+ for ($i = 3; $i <= $sqrtnum; $i += 2) {
+ next NUM unless $num % $i;
+ }
+ return $num;
+ }
+}
+
+1;