Attachment 683564 Details for Bug 891457 – part of a fix

[patch] part of a fix

0001-candidate-fix-for-over-flow.patch (text/plain), 4.24 KB, created by Hin-Tak Leung on 2013-01-20 14:27:56 UTC

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Creator: Hin-Tak Leung

Created: 2013-01-20 14:27:56 UTC

Size: 4.24 KB

patch

obsolete

>From 76e18c86c8def6df7c0acbf9a8c82d667d16ed25 Mon Sep 17 00:00:00 2001
>From: Hin-Tak Leung <htl10@users.sourceforge.net>
>Date: Sat, 19 Jan 2013 05:50:37 +0000
>Subject: [PATCH] candidate fix for over flow
>
>
>Signed-off-by: Hin-Tak Leung <htl10@users.sourceforge.net>
>---
> include/freetype/internal/ftcalc.h |  8 +++++++-
> src/base/ftcalc.c                  | 36 ++++++++++++++++++++++++++++++++++++
> src/base/ftoutln.c                 | 13 ++++++++++++-
> src/base/fttrigon.c                | 32 ++------------------------------
> 4 files changed, 57 insertions(+), 32 deletions(-)
>
>diff --git a/include/freetype/internal/ftcalc.h b/include/freetype/internal/ftcalc.h
>index 56aa07c..e4924d0 100644
>--- a/include/freetype/internal/ftcalc.h
>+++ b/include/freetype/internal/ftcalc.h
>@@ -125,7 +125,6 @@ FT_BEGIN_HEADER
>    *  A variant of FT_Vector_Transform.  See comments for
>    *  FT_Matrix_Multiply_Scaled.
>    */
>-
>   FT_BASE( void )
>   FT_Vector_Transform_Scaled( FT_Vector*        vector,
>                               const FT_Matrix*  matrix,
>@@ -156,6 +155,13 @@ FT_BEGIN_HEADER
>                      FT_Pos  out_y );
> 
> 
>+  /*
>+   *  Return the most significant bit index.
>+   */  
>+  FT_BASE( FT_Int )
>+  FT_MSB( FT_UInt32 z );
>+
>+
> #define INT_TO_F26DOT6( x )    ( (FT_Long)(x) << 6  )
> #define INT_TO_F2DOT14( x )    ( (FT_Long)(x) << 14 )
> #define INT_TO_FIXED( x )      ( (FT_Long)(x) << 16 )
>diff --git a/src/base/ftcalc.c b/src/base/ftcalc.c
>index 2aeea04..4122fda 100644
>--- a/src/base/ftcalc.c
>+++ b/src/base/ftcalc.c
>@@ -103,6 +103,42 @@
>   }
> 
> 
>+  FT_BASE_DEF ( FT_Int )
>+  FT_MSB( FT_UInt32 z )
>+  {
>+    FT_Int shift = 0;
>+
>+    /* determine msb bit index in `shift' */
>+    if ( z >= ( 1L << 16 ) )
>+    {
>+      z     >>= 16;
>+      shift  += 16;
>+    }
>+    if ( z >= ( 1L << 8 ) )
>+    {
>+      z     >>= 8;
>+      shift  += 8;
>+    }
>+    if ( z >= ( 1L << 4 ) )
>+    {
>+      z     >>= 4;
>+      shift  += 4;
>+    }
>+    if ( z >= ( 1L << 2 ) )
>+    {
>+      z     >>= 2;
>+      shift  += 2;
>+    }
>+    if ( z >= ( 1L << 1 ) )
>+    {
>+      z     >>= 1;
>+      shift  += 1;
>+    }
>+
>+    return shift;
>+  }
>+
>+
> #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
> 
>   /* documentation is in ftcalc.h */
>diff --git a/src/base/ftoutln.c b/src/base/ftoutln.c
>index 27aba01..875968c 100644
>--- a/src/base/ftoutln.c
>+++ b/src/base/ftoutln.c
>@@ -1009,6 +1009,8 @@
>   FT_EXPORT_DEF( FT_Orientation )
>   FT_Outline_Get_Orientation( FT_Outline*  outline )
>   {
>+    FT_BBox     cbox;
>+    FT_Int      xshift, yshift;
>     FT_Vector*  points;
>     FT_Vector   v_prev, v_cur;
>     FT_Int      c, n, first;
>@@ -1023,6 +1025,14 @@
>     /* cubic or quadratic curves, this test deals with the polygon    */
>     /* only which is spanned up by the control points.                */
> 
>+    FT_Outline_Get_CBox( outline, &cbox );
>+
>+    xshift = FT_MSB( FT_ABS( cbox.xMax ) | FT_ABS( cbox.xMin ) ) - 14;
>+    xshift = FT_MAX( xshift, 0 );
>+
>+    yshift = FT_MSB( cbox.yMax - cbox.yMin ) - 14;
>+    yshift = FT_MAX( yshift, 0 );
>+
>     points = outline->points;
> 
>     first = 0;
>@@ -1036,7 +1046,8 @@
>       for ( n = first; n <= last; n++ )
>       {
>         v_cur = points[n];
>-        area += ( v_cur.y - v_prev.y ) * ( v_cur.x + v_prev.x );
>+        area += ( ( v_cur.y - v_prev.y ) >> yshift ) * 
>+                ( ( v_cur.x + v_prev.x ) >> xshift );
>         v_prev = v_cur;
>       }
> 
>diff --git a/src/base/fttrigon.c b/src/base/fttrigon.c
>index 4bd4320..e8cc3e3 100644
>--- a/src/base/fttrigon.c
>+++ b/src/base/fttrigon.c
>@@ -118,42 +118,14 @@
>   static FT_Int
>   ft_trig_prenorm( FT_Vector*  vec )
>   {
>-    FT_Fixed  x, y, z;
>+    FT_Fixed  x, y;
>     FT_Int    shift;
> 
> 
>     x = vec->x;
>     y = vec->y;
> 
>-    z     = FT_ABS( x ) | FT_ABS( y );
>-    shift = 0;
>-
>-    /* determine msb bit index in `shift' */
>-    if ( z >= ( 1L << 16 ) )
>-    {
>-      z     >>= 16;
>-      shift  += 16;
>-    }
>-    if ( z >= ( 1L << 8 ) )
>-    {
>-      z     >>= 8;
>-      shift  += 8;
>-    }
>-    if ( z >= ( 1L << 4 ) )
>-    {
>-      z     >>= 4;
>-      shift  += 4;
>-    }
>-    if ( z >= ( 1L << 2 ) )
>-    {
>-      z     >>= 2;
>-      shift  += 2;
>-    }
>-    if ( z >= ( 1L << 1 ) )
>-    {
>-      z    >>= 1;
>-      shift += 1;
>-    }
>+    shift = FT_MSB( FT_ABS( x ) | FT_ABS( y ) );
> 
>     if ( shift <= FT_TRIG_SAFE_MSB )
>     {
>-- 
>1.8.1
>

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Attachments on bug 891457: 671807 | 671809 | 671810 | 671811 | 671812 | 674513 | 677638 | 677639 | 677640 | 677641 | 677643 | 678118 | 678121 | 683564 | 689537 | 711682 | 711683