[psaux] Fix assertions.
* src/psaux/pshints.c (cf2_hintmap_adjustHints): Check for overflow
before emitting an assertion error.
diff --git a/ChangeLog b/ChangeLog
index e236039..02fc1a5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2021-06-12 Werner Lemberg <wl@gnu.org>
+
+ [psaux] Fix assertions.
+
+ * src/psaux/pshints.c (cf2_hintmap_adjustHints): Check for overflow
+ before emitting an assertion error.
+
2021-06-09 Alexei Podtelezhnikov <apodtele@gmail.com>
* src/truetype/ttinterp.c (TT_RunIns): Optimize tracing.
diff --git a/src/psaux/pshints.c b/src/psaux/pshints.c
index f6e6dd5..ad472c9 100644
--- a/src/psaux/pshints.c
+++ b/src/psaux/pshints.c
@@ -412,6 +412,12 @@
{
FT_Bool isPair = cf2_hint_isPair( &hintmap->edge[i] );
+ /* final amount to move edge or edge pair */
+ CF2_Fixed move = 0;
+
+ CF2_Fixed dsCoord_i;
+ CF2_Fixed dsCoord_j;
+
/* index of upper edge (same value for ghost hint) */
j = isPair ? i + 1 : i;
@@ -422,11 +428,14 @@
FT_ASSERT( cf2_hint_isLocked( &hintmap->edge[i] ) ==
cf2_hint_isLocked( &hintmap->edge[j] ) );
+ dsCoord_i = hintmap->edge[i].dsCoord;
+ dsCoord_j = hintmap->edge[j].dsCoord;
+
if ( !cf2_hint_isLocked( &hintmap->edge[i] ) )
{
/* hint edge is not locked, we can adjust it */
- CF2_Fixed fracDown = cf2_fixedFraction( hintmap->edge[i].dsCoord );
- CF2_Fixed fracUp = cf2_fixedFraction( hintmap->edge[j].dsCoord );
+ CF2_Fixed fracDown = cf2_fixedFraction( dsCoord_i );
+ CF2_Fixed fracUp = cf2_fixedFraction( dsCoord_j );
/* calculate all four possibilities; moves down are negative */
CF2_Fixed downMoveDown = 0 - fracDown;
@@ -443,9 +452,6 @@
/* smallest move down */
CF2_Fixed moveDown = FT_MAX( downMoveDown, upMoveDown );
- /* final amount to move edge or edge pair */
- CF2_Fixed move;
-
CF2_Fixed downMinCounter = CF2_MIN_COUNTER;
CF2_Fixed upMinCounter = CF2_MIN_COUNTER;
FT_Bool saveEdge = FALSE;
@@ -467,16 +473,14 @@
/* is there room to move up? */
/* there is if we are at top of array or the next edge is at or */
/* beyond proposed move up? */
- if ( j >= hintmap->count - 1 ||
+ if ( j >= hintmap->count - 1 ||
hintmap->edge[j + 1].dsCoord >=
- ADD_INT32( hintmap->edge[j].dsCoord,
- moveUp + upMinCounter ) )
+ ADD_INT32( dsCoord_j, moveUp + upMinCounter ) )
{
/* there is room to move up; is there also room to move down? */
- if ( i == 0 ||
+ if ( i == 0 ||
hintmap->edge[i - 1].dsCoord <=
- ADD_INT32( hintmap->edge[i].dsCoord,
- moveDown - downMinCounter ) )
+ ADD_INT32( dsCoord_i, moveDown - downMinCounter ) )
{
/* move smaller absolute amount */
move = ( -moveDown < moveUp ) ? moveDown : moveUp; /* optimum */
@@ -487,10 +491,9 @@
else
{
/* is there room to move down? */
- if ( i == 0 ||
+ if ( i == 0 ||
hintmap->edge[i - 1].dsCoord <=
- ADD_INT32( hintmap->edge[i].dsCoord,
- moveDown - downMinCounter ) )
+ ADD_INT32( dsCoord_i, moveDown - downMinCounter ) )
{
move = moveDown;
/* true if non-optimum move */
@@ -524,17 +527,21 @@
}
/* move the edge(s) */
- hintmap->edge[i].dsCoord = ADD_INT32( hintmap->edge[i].dsCoord,
- move );
+ hintmap->edge[i].dsCoord = ADD_INT32( dsCoord_i, move );
if ( isPair )
- hintmap->edge[j].dsCoord = ADD_INT32( hintmap->edge[j].dsCoord,
- move );
+ hintmap->edge[j].dsCoord = ADD_INT32( dsCoord_j, move );
}
- /* assert there are no overlaps in device space */
+ /* assert there are no overlaps in device space; */
+ /* ignore tests if there was overflow (that is, if */
+ /* operands have the same sign but the sum does not) */
FT_ASSERT( i == 0 ||
+ ( ( dsCoord_i ^ move ) >= 0 &&
+ ( dsCoord_i ^ hintmap->edge[i].dsCoord ) < 0 ) ||
hintmap->edge[i - 1].dsCoord <= hintmap->edge[i].dsCoord );
FT_ASSERT( i < j ||
+ ( ( dsCoord_j ^ move ) >= 0 &&
+ ( dsCoord_j ^ hintmap->edge[j].dsCoord ) < 0 ) ||
hintmap->edge[i].dsCoord <= hintmap->edge[j].dsCoord );
/* adjust the scales, avoiding divide by zero */
