[Gnash-commit] /srv/bzr/gnash/trunk r9843: Fix bug #24363.

[Benjamin Wolsey]

------------------------------------------------------------
revno: 9843
committer: Benjamin Wolsey <address@hidden>
branch nick: trunk
timestamp: Thu 2008-09-25 16:51:42 +0200
message:
  Fix bug #24363.
modified:
  libcore/character.cpp
  testsuite/actionscript.all/Transform.as
    ------------------------------------------------------------
    revno: 9842.1.1
    committer: Benjamin Wolsey <address@hidden>
    branch nick: work
    timestamp: Thu 2008-09-25 16:23:50 +0200
    message:
      Fix undefined behaviour overflow bugginess.
    modified:
      libcore/character.cpp
    ------------------------------------------------------------
    revno: 9842.1.2
    committer: Benjamin Wolsey <address@hidden>
    branch nick: work
    timestamp: Thu 2008-09-25 16:26:24 +0200
    message:
      Test passes also on 64-bit machines now.
    modified:
      testsuite/actionscript.all/Transform.as

=== modified file 'libcore/character.cpp'
--- a/libcore/character.cpp     2008-09-18 06:49:30 +0000
+++ b/libcore/character.cpp     2008-09-25 14:23:50 +0000
@@ -404,22 +404,37 @@
        else // setter
        {
                const as_value& inval = fn.arg(0);
-               const double input = inval.to_number();
-               if ( inval.is_undefined() || inval.is_null() || ! 
utility::isFinite(input) )
+
+        // The new internal alpha value is input / 100.0 * 256.
+        // We test for finiteness later, but the multiplication
+        // won't make any difference.
+               const double newAlpha = inval.to_number() * 2.56;
+
+        if ( inval.is_undefined() || inval.is_null() ||
+                !utility::isFinite(newAlpha) )
                {
                        IF_VERBOSE_ASCODING_ERRORS(
-                       log_aserror(_("Ignored attempt to set %s.%s=%s"),
-                               ptr->getTarget(),
-                               _("_alpha"), // trying to reuse translations
-                               fn.arg(0));
+                       log_aserror(_("Ignored attempt to set %s._alpha=%s"),
+                               ptr->getTarget(), fn.arg(0));
                        );
                        return rv;
                }
-               // set alpha = input / 100.0 * 256 = input * 2.56;
-               cxform  cx = ptr->get_cxform();
-               cx.aa = (boost::int16_t)(input * 2.56); 
+
+        cxform cx = ptr->get_cxform();
+
+        // Overflows are *not* truncated, but set to -32768.
+        if (newAlpha > std::numeric_limits<boost::int16_t>::max() ||
+            newAlpha < std::numeric_limits<boost::int16_t>::min())
+        {
+            cx.aa = std::numeric_limits<boost::int16_t>::min();
+        }
+        else
+        {
+            cx.aa = static_cast<boost::int16_t>(newAlpha);
+        }
+
         ptr->set_cxform(cx);
-               ptr->transformedByScript(); // m_accept_anim_moves = false; 
+               ptr->transformedByScript();  
        }
        return rv;
 

=== modified file 'testsuite/actionscript.all/Transform.as'
--- a/testsuite/actionscript.all/Transform.as   2008-09-25 12:58:38 +0000
+++ b/testsuite/actionscript.all/Transform.as   2008-09-25 14:26:24 +0000
@@ -90,7 +90,7 @@
 check_equals(mcx.transform.colorTransform.toString(), "(redMultiplier=1, 
greenMultiplier=1, blueMultiplier=1, alphaMultiplier=-0.98828125, redOffset=0, 
greenOffset=0, blueOffset=0, alphaOffset=0)");
 
 mcx._alpha = 13000;
-xcheck_equals(mcx.transform.colorTransform.toString(), "(redMultiplier=1, 
greenMultiplier=1, blueMultiplier=1, alphaMultiplier=-128, redOffset=0, 
greenOffset=0, blueOffset=0, alphaOffset=0)");
+check_equals(mcx.transform.colorTransform.toString(), "(redMultiplier=1, 
greenMultiplier=1, blueMultiplier=1, alphaMultiplier=-128, redOffset=0, 
greenOffset=0, blueOffset=0, alphaOffset=0)");
 
 r = new ColorTransform(2, 3, 4, 5, 5, -5, 5, -5);
 mcx.transform.colorTransform = r;