Fix, GSSimpleLayoutManager

[Georg Fleischmann]

Hi,

here are some small fixes for GSSimpleLayoutManager which check the array  
count of _lineLayoutInformation before accessing the array.
The modifications allow (for example) a text box of zero size without getting  
an exception.

Georg


2002-05-17  Georg Fleischmann

        * gui/Source/GSSimpleLayoutManager.m
        [GSSimpleLayoutManager -lineLayoutIndexForPoint:]:
        cast the count of _lineLayoutInformation to integer in MAX().
        test if max is zero.
        [GSSimpleLayoutManager -glyphRangeForLineLayoutRange:]:
        test if count of _lineLayoutInformation is zero
        [GSSimpleLayoutManager -drawLinesInLineRange:]:
        test if count of _lineLayoutInformation is inside range


*** gui/Source/GSSimpleLayoutManager.m.old      Tue Mar 26 20:00:18 2002
--- gui/Source/GSSimpleLayoutManager.m  Fri May 17 20:27:44 2002
***************
*** 542,553 ****
  {
    int i;
    int min = 0;
!   int max = MAX(0, [_lineLayoutInformation count] - 1);
    float y = point.y;
!   float fmin = NSMinY([[_lineLayoutInformation objectAtIndex: 0]  
lineFragmentRect]);
!   float fmax = NSMaxY([[_lineLayoutInformation lastObject] lineFragmentRect]);
    NSRect rect;

    if (y >= fmax)
      return max;

--- 542,559 ----
  {
    int i;
    int min = 0;
!   int max = MAX(0, (int)[_lineLayoutInformation count] - 1);
    float y = point.y;
!   float fmin;
!   float fmax;
    NSRect rect;

+   if (!max)
+     return 0;
+
+   fmin = NSMinY([[_lineLayoutInformation objectAtIndex: 0] lineFragmentRect]);
+   fmax = NSMaxY([[_lineLayoutInformation lastObject] lineFragmentRect]);
+
    if (y >= fmax)
      return max;

***************
*** 636,641 ****
--- 642,649 ----
    unsigned startIndex;
    unsigned endIndex;

+   if ([_lineLayoutInformation count] == 0)
+     return NSMakeRange(0, 0);
    if (startLine >= [_lineLayoutInformation count])
      currentInfo = [_lineLayoutInformation lastObject];
    else
***************
*** 727,736 ****
  // relies on _lineLayoutInformation
  - (void) drawLinesInLineRange: (NSRange)aRange;
  {
!   NSArray *linesToDraw = [_lineLayoutInformation subarrayWithRange: aRange];
    NSEnumerator *lineEnum;
    _GNULineLayoutInfo *currentInfo;

    for ((lineEnum = [linesToDraw objectEnumerator]);
         (currentInfo = [lineEnum nextObject]);)
      {
--- 735,747 ----
  // relies on _lineLayoutInformation
  - (void) drawLinesInLineRange: (NSRange)aRange;
  {
!   NSArray *linesToDraw;
    NSEnumerator *lineEnum;
    _GNULineLayoutInfo *currentInfo;

+   if ([_lineLayoutInformation count] < aRange.location+aRange.length)
+     return;
+   linesToDraw = [_lineLayoutInformation subarrayWithRange: aRange];
    for ((lineEnum = [linesToDraw objectEnumerator]);
         (currentInfo = [lineEnum nextObject]);)
      {