Fix shifting more bits than the length of the window

[perl/modules/Scalar-Vec-Util.git] / lib / Scalar / Vec / Util.pm

diff --git a/lib/Scalar/Vec/Util.pm b/lib/Scalar/Vec/Util.pm
index c80d6424c1c4dc920c4b9729053a7fd271b00a81..b5a8080e7f235a1cde6ca7693f59dd9547d92af0 100644 (file)
--- a/lib/Scalar/Vec/Util.pm
+++ b/lib/Scalar/Vec/Util.pm
@@ -81,8 +81,17 @@ sub vfill_pp {
  (undef, my $s, my $l, my $x) = @_;
  croak "Invalid argument" unless _alldef @_;
  return unless $l;
- $x = 1 if $x;
- vec($_[0], $_, 1) = $x for $s .. $s + $l - 1;
+ $x = ~0 if $x;
+ my $SIZE = 32;
+ my $t = int($s / $SIZE) + 1;
+ my $u = int(($s + $l) / $SIZE);
+ if ($SIZE * $t < $s + $l and $t <= $u) {
+  vec($_[0], $_, 1)     = $x for $s .. $SIZE * $t - 1;
+  vec($_[0], $_, $SIZE) = $x for $t .. $u - 1;
+  vec($_[0], $_, 1)     = $x for $SIZE * $u .. $s + $l - 1;
+ } else {
+  vec($_[0], $_, 1) = $x for $s .. $s + $l - 1;
+ }
 }
 
 =head2 C<< vcopy $from => $from_start, $to => $to_start, $length >>
@@ -123,14 +132,17 @@ sub vshift {
   $left = 0;
   $bits = -$bits;
  }
- $bits    = $length if $bits > $length;
- $length -= $bits;
- if ($left) {
-  vcopy($_[0], $start, $_[0], $start + $bits, $length);
-  vfill($_[0], $start, $bits, $insert) if defined $insert;
+ if ($bits < $length) {
+  $length -= $bits;
+  if ($left) {
+   vcopy($_[0], $start, $_[0], $start + $bits, $length);
+   vfill($_[0], $start, $bits, $insert) if defined $insert;
+  } else {
+   vcopy($_[0], $start + $bits, $_[0], $start, $length);
+   vfill($_[0], $start + $length, $bits, $insert) if defined $insert;
+  }
  } else {
-  vcopy($_[0], $start + $bits, $_[0], $start, $length);
-  vfill($_[0], $start + $length, $bits, $insert) if defined $insert;
+  vfill($_[0], $start, $length, $insert) if defined $insert;
  }
 }