Commit message: None
CVE: CVE-2010-2498
CWE: CWE-399
Vulnerability description: The psh_glyph_find_strong_points function in pshinter/pshalgo.c in FreeType before 2.4.0 does not properly implement hinting masks, which allows remote attackers to cause a denial of service (heap memory corruption and application crash) or possibly execute arbitrary code via a crafted font file that triggers an invalid free operation.

Project: savannah

  ps_hints_apply( PS_Hints        ps_hints,
                  FT_Outline*     outline,
                  PSH_Globals     globals,
                  FT_Render_Mode  hint_mode )
  {
    PSH_GlyphRec  glyphrec;
    PSH_Glyph     glyph = &glyphrec;
    FT_Error      error;
#ifdef DEBUG_HINTER
    FT_Memory     memory;
#endif
    FT_Int        dimension;


    /* something to do? */
    if ( outline->n_points == 0 || outline->n_contours == 0 )
      return PSH_Err_Ok;

#ifdef DEBUG_HINTER

    memory = globals->memory;

    if ( ps_debug_glyph )
    {
      psh_glyph_done( ps_debug_glyph );
      FT_FREE( ps_debug_glyph );
    }

    if ( FT_NEW( glyph ) )
      return error;

    ps_debug_glyph = glyph;

#endif /* DEBUG_HINTER */

    error = psh_glyph_init( glyph, outline, ps_hints, globals );
    if ( error )
      goto Exit;

    /* try to optimize the y_scale so that the top of non-capital letters
     * is aligned on a pixel boundary whenever possible
     */
    {
      PSH_Dimension  dim_x = &glyph->globals->dimension[0];
      PSH_Dimension  dim_y = &glyph->globals->dimension[1];

      FT_Fixed  x_scale = dim_x->scale_mult;
      FT_Fixed  y_scale = dim_y->scale_mult;

      FT_Fixed  old_x_scale = x_scale;
      FT_Fixed  old_y_scale = y_scale;

      FT_Fixed  scaled;
      FT_Fixed  fitted;

      FT_Bool  rescale = FALSE;


      scaled = FT_MulFix( globals->blues.normal_top.zones->org_ref, y_scale );
      fitted = FT_PIX_ROUND( scaled );

      if ( fitted != 0 && scaled != fitted )
      {
        rescale = TRUE;

        y_scale = FT_MulDiv( y_scale, fitted, scaled );

        if ( fitted < scaled )
          x_scale -= x_scale / 50;

        psh_globals_set_scale( glyph->globals, x_scale, y_scale, 0, 0 );
      }

      glyph->do_horz_hints = 1;
      glyph->do_vert_hints = 1;

      glyph->do_horz_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO ||
                                         hint_mode == FT_RENDER_MODE_LCD  );

      glyph->do_vert_snapping = FT_BOOL( hint_mode == FT_RENDER_MODE_MONO  ||
                                         hint_mode == FT_RENDER_MODE_LCD_V );

      glyph->do_stem_adjust   = FT_BOOL( hint_mode != FT_RENDER_MODE_LIGHT );

      for ( dimension = 0; dimension < 2; dimension++ )
      {
        /* load outline coordinates into glyph */
        psh_glyph_load_points( glyph, dimension );

        /* compute local extrema */
        psh_glyph_compute_extrema( glyph );

        /* compute aligned stem/hints positions */
        psh_hint_table_align_hints( &glyph->hint_tables[dimension],
                                    glyph->globals,
                                    dimension,
                                    glyph );

        /* find strong points, align them, then interpolate others */
        psh_glyph_find_strong_points( glyph, dimension );
        if ( dimension == 1 )
          psh_glyph_find_blue_points( &globals->blues, glyph );
        psh_glyph_interpolate_strong_points( glyph, dimension );
        psh_glyph_interpolate_normal_points( glyph, dimension );
        psh_glyph_interpolate_other_points( glyph, dimension );

        /* save hinted coordinates back to outline */
        psh_glyph_save_points( glyph, dimension );

        if ( rescale )
          psh_globals_set_scale( glyph->globals,
                                 old_x_scale, old_y_scale, 0, 0 );
      }
    }

  Exit:

#ifndef DEBUG_HINTER
    psh_glyph_done( glyph );
#endif

    return error;
  }

Project: savannah

  ps_simple_scale( PSH_Hint_Table  table,
                   FT_Fixed        scale,
                   FT_Fixed        delta,
                   FT_Int          dimension )
  {
    PSH_Hint  hint;
    FT_UInt   count;


    for ( count = 0; count < table->max_hints; count++ )
    {
      hint = table->hints + count;

      hint->cur_pos = FT_MulFix( hint->org_pos, scale ) + delta;
      hint->cur_len = FT_MulFix( hint->org_len, scale );

      if ( ps_debug_hint_func )
        ps_debug_hint_func( hint, dimension );
    }
  }

Project: savannah

  psh_compute_dir( FT_Pos  dx,
                   FT_Pos  dy )
  {
    FT_Pos  ax, ay;
    int     result = PSH_DIR_NONE;


    ax = ( dx >= 0 ) ? dx : -dx;
    ay = ( dy >= 0 ) ? dy : -dy;

    if ( ay * 12 < ax )
    {
      /* |dy| <<< |dx|  means a near-horizontal segment */
      result = ( dx >= 0 ) ? PSH_DIR_RIGHT : PSH_DIR_LEFT;
    }
    else if ( ax * 12 < ay )
    {
      /* |dx| <<< |dy|  means a near-vertical segment */
      result = ( dy >= 0 ) ? PSH_DIR_UP : PSH_DIR_DOWN;
    }

    return result;
  }

Project: savannah

  psh_corner_is_flat( FT_Pos  x_in,
                      FT_Pos  y_in,
                      FT_Pos  x_out,
                      FT_Pos  y_out )
  {
    FT_Pos  ax = x_in;
    FT_Pos  ay = y_in;

    FT_Pos  d_in, d_out, d_corner;


    if ( ax < 0 )
      ax = -ax;
    if ( ay < 0 )
      ay = -ay;
    d_in = ax + ay;

    ax = x_out;
    if ( ax < 0 )
      ax = -ax;
    ay = y_out;
    if ( ay < 0 )
      ay = -ay;
    d_out = ax + ay;

    ax = x_out + x_in;
    if ( ax < 0 )
      ax = -ax;
    ay = y_out + y_in;
    if ( ay < 0 )
      ay = -ay;
    d_corner = ax + ay;

    return ( d_in + d_out - d_corner ) < ( d_corner >> 4 );
  }

Project: savannah

  psh_corner_orientation( FT_Pos  in_x,
                          FT_Pos  in_y,
                          FT_Pos  out_x,
                          FT_Pos  out_y )
  {
    FT_Int  result;


    /* deal with the trivial cases quickly */
    if ( in_y == 0 )
    {
      if ( in_x >= 0 )
        result = out_y;
      else
        result = -out_y;
    }
    else if ( in_x == 0 )
    {
      if ( in_y >= 0 )
        result = -out_x;
      else
        result = out_x;
    }
    else if ( out_y == 0 )
    {
      if ( out_x >= 0 )
        result = in_y;
      else
        result = -in_y;
    }
    else if ( out_x == 0 )
    {
      if ( out_y >= 0 )
        result = -in_x;
      else
        result =  in_x;
    }
    else /* general case */
    {
      long long  delta = (long long)in_x * out_y - (long long)in_y * out_x;

      if ( delta == 0 )
        result = 0;
      else
        result = 1 - 2 * ( delta < 0 );
    }

    return result;
  }

Project: savannah

  psh_dimension_quantize_len( PSH_Dimension  dim,
                              FT_Pos         len,
                              FT_Bool        do_snapping )
  {
    if ( len <= 64 )
      len = 64;
    else
    {
      FT_Pos  delta = len - dim->stdw.widths[0].cur;


      if ( delta < 0 )
        delta = -delta;

      if ( delta < 40 )
      {
        len = dim->stdw.widths[0].cur;
        if ( len < 48 )
          len = 48;
      }

      if ( len < 3 * 64 )
      {
        delta = ( len & 63 );
        len  &= -64;

        if ( delta < 10 )
          len += delta;

        else if ( delta < 32 )
          len += 10;

        else if ( delta < 54 )
          len += 54;

        else
          len += delta;
      }
      else
        len = FT_PIX_ROUND( len );
    }

    if ( do_snapping )
      len = FT_PIX_ROUND( len );

    return  len;
  }

Project: savannah

  psh_glyph_compute_inflections( PSH_Glyph  glyph )
  {
    FT_UInt  n;


    for ( n = 0; n < glyph->num_contours; n++ )
    {
      PSH_Point  first, start, end, before, after;
      FT_Pos     in_x, in_y, out_x, out_y;
      FT_Int     orient_prev, orient_cur;
      FT_Int     finished = 0;


      /* we need at least 4 points to create an inflection point */
      if ( glyph->contours[n].count < 4 )
        continue;

      /* compute first segment in contour */
      first = glyph->contours[n].start;

      start = end = first;
      do
      {
        end = end->next;
        if ( end == first )
          goto Skip;

        in_x = end->org_u - start->org_u;
        in_y = end->org_v - start->org_v;

      } while ( in_x == 0 && in_y == 0 );

      /* extend the segment start whenever possible */
      before = start;
      do
      {
        do
        {
          start  = before;
          before = before->prev;
          if ( before == first )
            goto Skip;

          out_x = start->org_u - before->org_u;
          out_y = start->org_v - before->org_v;

        } while ( out_x == 0 && out_y == 0 );

        orient_prev = psh_corner_orientation( in_x, in_y, out_x, out_y );

      } while ( orient_prev == 0 );

      first = start;
      in_x  = out_x;
      in_y  = out_y;

      /* now, process all segments in the contour */
      do
      {
        /* first, extend current segment's end whenever possible */
        after = end;
        do
        {
          do
          {
            end   = after;
            after = after->next;
            if ( after == first )
              finished = 1;

            out_x = after->org_u - end->org_u;
            out_y = after->org_v - end->org_v;

          } while ( out_x == 0 && out_y == 0 );

          orient_cur = psh_corner_orientation( in_x, in_y, out_x, out_y );

        } while ( orient_cur == 0 );

        if ( ( orient_cur ^ orient_prev ) < 0 )
        {
          do
          {
            psh_point_set_inflex( start );
            start = start->next;
          }
          while ( start != end );

          psh_point_set_inflex( start );
        }

        start       = end;
        end         = after;
        orient_prev = orient_cur;
        in_x        = out_x;
        in_y        = out_y;

      } while ( !finished );

    Skip:
      ;
    }
  }

Project: savannah

  psh_glyph_done( PSH_Glyph  glyph )
  {
    FT_Memory  memory = glyph->memory;


    psh_hint_table_done( &glyph->hint_tables[1], memory );
    psh_hint_table_done( &glyph->hint_tables[0], memory );

    FT_FREE( glyph->points );
    FT_FREE( glyph->contours );

    glyph->num_points   = 0;
    glyph->num_contours = 0;

    glyph->memory = 0;
  }

Project: savannah

  psh_glyph_find_blue_points( PSH_Blues  blues,
                              PSH_Glyph  glyph )
  {
    PSH_Blue_Table  table;
    PSH_Blue_Zone   zone;
    FT_UInt         glyph_count = glyph->num_points;
    FT_UInt         blue_count;
    PSH_Point       point = glyph->points;


    for ( ; glyph_count > 0; glyph_count--, point++ )
    {
      FT_Pos  y;


      /* check tangents */
      if ( !PSH_DIR_COMPARE( point->dir_in,  PSH_DIR_HORIZONTAL ) &&
           !PSH_DIR_COMPARE( point->dir_out, PSH_DIR_HORIZONTAL ) )
        continue;

      /* skip strong points */
      if ( psh_point_is_strong( point ) )
        continue;

      y = point->org_u;

      /* look up top zones */
      table      = &blues->normal_top;
      blue_count = table->count;
      zone       = table->zones;

      for ( ; blue_count > 0; blue_count--, zone++ )
      {
        FT_Pos  delta = y - zone->org_bottom;


        if ( delta < -blues->blue_fuzz )
          break;

        if ( y <= zone->org_top + blues->blue_fuzz )
          if ( blues->no_overshoots || delta <= blues->blue_threshold )
          {
            point->cur_u = zone->cur_bottom;
            psh_point_set_strong( point );
            psh_point_set_fitted( point );
          }
      }

      /* look up bottom zones */
      table      = &blues->normal_bottom;
      blue_count = table->count;
      zone       = table->zones + blue_count - 1;

      for ( ; blue_count > 0; blue_count--, zone-- )
      {
        FT_Pos  delta = zone->org_top - y;


        if ( delta < -blues->blue_fuzz )
          break;

        if ( y >= zone->org_bottom - blues->blue_fuzz )
          if ( blues->no_overshoots || delta < blues->blue_threshold )
          {
            point->cur_u = zone->cur_top;
            psh_point_set_strong( point );
            psh_point_set_fitted( point );
          }
      }
    }
  }

Project: savannah

  psh_glyph_interpolate_normal_points( PSH_Glyph  glyph,
                                       FT_Int     dimension )
  {

#if 1
    /* first technique: a point is strong if it is a local extremum */

    PSH_Dimension  dim    = &glyph->globals->dimension[dimension];
    FT_Fixed       scale  = dim->scale_mult;
    FT_Memory      memory = glyph->memory;

    PSH_Point*     strongs     = NULL;
    PSH_Point      strongs_0[PSH_MAX_STRONG_INTERNAL];
    FT_UInt        num_strongs = 0;

    PSH_Point      points = glyph->points;
    PSH_Point      points_end = points + glyph->num_points;
    PSH_Point      point;


    /* first count the number of strong points */
    for ( point = points; point < points_end; point++ )
    {
      if ( psh_point_is_strong( point ) )
        num_strongs++;
    }

    if ( num_strongs == 0 )  /* nothing to do here */
      return;

    /* allocate an array to store a list of points, */
    /* stored in increasing org_u order             */
    if ( num_strongs <= PSH_MAX_STRONG_INTERNAL )
      strongs = strongs_0;
    else
    {
      FT_Error  error;


      if ( FT_NEW_ARRAY( strongs, num_strongs ) )
        return;
    }

    num_strongs = 0;
    for ( point = points; point < points_end; point++ )
    {
      PSH_Point*  insert;


      if ( !psh_point_is_strong( point ) )
        continue;

      for ( insert = strongs + num_strongs; insert > strongs; insert-- )
      {
        if ( insert[-1]->org_u <= point->org_u )
          break;

        insert[0] = insert[-1];
      }
      insert[0] = point;
      num_strongs++;
    }

    /* now try to interpolate all normal points */
    for ( point = points; point < points_end; point++ )
    {
      if ( psh_point_is_strong( point ) )
        continue;

      /* sometimes, some local extrema are smooth points */
      if ( psh_point_is_smooth( point ) )
      {
        if ( point->dir_in == PSH_DIR_NONE   ||
             point->dir_in != point->dir_out )
          continue;

        if ( !psh_point_is_extremum( point ) &&
             !psh_point_is_inflex( point )   )
          continue;

        point->flags &= ~PSH_POINT_SMOOTH;
      }

      /* find best enclosing point coordinates then interpolate */
      {
        PSH_Point   before, after;
        FT_UInt     nn;


        for ( nn = 0; nn < num_strongs; nn++ )
          if ( strongs[nn]->org_u > point->org_u )
            break;

        if ( nn == 0 )  /* point before the first strong point */
        {
          after = strongs[0];

          point->cur_u = after->cur_u +
                           FT_MulFix( point->org_u - after->org_u,
                                      scale );
        }
        else
        {
          before = strongs[nn - 1];

          for ( nn = num_strongs; nn > 0; nn-- )
            if ( strongs[nn - 1]->org_u < point->org_u )
              break;

          if ( nn == num_strongs )  /* point is after last strong point */
          {
            before = strongs[nn - 1];

            point->cur_u = before->cur_u +
                             FT_MulFix( point->org_u - before->org_u,
                                        scale );
          }
          else
          {
            FT_Pos  u;


            after = strongs[nn];

            /* now interpolate point between before and after */
            u = point->org_u;

            if ( u == before->org_u )
              point->cur_u = before->cur_u;

            else if ( u == after->org_u )
              point->cur_u = after->cur_u;

            else
              point->cur_u = before->cur_u +
                               FT_MulDiv( u - before->org_u,
                                          after->cur_u - before->cur_u,
                                          after->org_u - before->org_u );
          }
        }
        psh_point_set_fitted( point );
      }
    }

    if ( strongs != strongs_0 )
      FT_FREE( strongs );

#endif /* 1 */

  }

Project: savannah

  psh_glyph_interpolate_other_points( PSH_Glyph  glyph,
                                      FT_Int     dimension )
  {
    PSH_Dimension  dim          = &glyph->globals->dimension[dimension];
    FT_Fixed       scale        = dim->scale_mult;
    FT_Fixed       delta        = dim->scale_delta;
    PSH_Contour    contour      = glyph->contours;
    FT_UInt        num_contours = glyph->num_contours;


    for ( ; num_contours > 0; num_contours--, contour++ )
    {
      PSH_Point  start = contour->start;
      PSH_Point  first, next, point;
      FT_UInt    fit_count;


      /* count the number of strong points in this contour */
      next      = start + contour->count;
      fit_count = 0;
      first     = 0;

      for ( point = start; point < next; point++ )
        if ( psh_point_is_fitted( point ) )
        {
          if ( !first )
            first = point;

          fit_count++;
        }

      /* if there are less than 2 fitted points in the contour, we */
      /* simply scale and eventually translate the contour points  */
      if ( fit_count < 2 )
      {
        if ( fit_count == 1 )
          delta = first->cur_u - FT_MulFix( first->org_u, scale );

        for ( point = start; point < next; point++ )
          if ( point != first )
            point->cur_u = FT_MulFix( point->org_u, scale ) + delta;

        goto Next_Contour;
      }

      /* there are more than 2 strong points in this contour; we */
      /* need to interpolate weak points between them            */
      start = first;
      do
      {
        point = first;

        /* skip consecutive fitted points */
        for (;;)
        {
          next = first->next;
          if ( next == start )
            goto Next_Contour;

          if ( !psh_point_is_fitted( next ) )
            break;

          first = next;
        }

        /* find next fitted point after unfitted one */
        for (;;)
        {
          next = next->next;
          if ( psh_point_is_fitted( next ) )
            break;
        }

        /* now interpolate between them */
        {
          FT_Pos    org_a, org_ab, cur_a, cur_ab;
          FT_Pos    org_c, org_ac, cur_c;
          FT_Fixed  scale_ab;


          if ( first->org_u <= next->org_u )
          {
            org_a  = first->org_u;
            cur_a  = first->cur_u;
            org_ab = next->org_u - org_a;
            cur_ab = next->cur_u - cur_a;
          }
          else
          {
            org_a  = next->org_u;
            cur_a  = next->cur_u;
            org_ab = first->org_u - org_a;
            cur_ab = first->cur_u - cur_a;
          }

          scale_ab = 0x10000L;
          if ( org_ab > 0 )
            scale_ab = FT_DivFix( cur_ab, org_ab );

          point = first->next;
          do
          {
            org_c  = point->org_u;
            org_ac = org_c - org_a;

            if ( org_ac <= 0 )
            {
              /* on the left of the interpolation zone */
              cur_c = cur_a + FT_MulFix( org_ac, scale );
            }
            else if ( org_ac >= org_ab )
            {
              /* on the right on the interpolation zone */
              cur_c = cur_a + cur_ab + FT_MulFix( org_ac - org_ab, scale );
            }
            else
            {
              /* within the interpolation zone */
              cur_c = cur_a + FT_MulFix( org_ac, scale_ab );
            }

            point->cur_u = cur_c;

            point = point->next;

          } while ( point != next );
        }

        /* keep going until all points in the contours have been processed */
        first = next;

      } while ( first != start );

    Next_Contour:
      ;
    }
  }

Project: savannah

  psh_glyph_load_points( PSH_Glyph  glyph,
                         FT_Int     dimension )
  {
    FT_Vector*  vec   = glyph->outline->points;
    PSH_Point   point = glyph->points;
    FT_UInt     count = glyph->num_points;


    for ( ; count > 0; count--, point++, vec++ )
    {
      point->flags2 = 0;
      point->hint   = NULL;
      if ( dimension == 0 )
      {
        point->org_u = vec->x;
        point->org_v = vec->y;
      }
      else
      {
        point->org_u = vec->y;
        point->org_v = vec->x;
      }

#ifdef DEBUG_HINTER
      point->org_x = vec->x;
      point->org_y = vec->y;
#endif

    }
  }

Project: savannah

  psh_glyph_save_points( PSH_Glyph  glyph,
                         FT_Int     dimension )
  {
    FT_UInt     n;
    PSH_Point   point = glyph->points;
    FT_Vector*  vec   = glyph->outline->points;
    char*       tags  = glyph->outline->tags;


    for ( n = 0; n < glyph->num_points; n++ )
    {
      if ( dimension == 0 )
        vec[n].x = point->cur_u;
      else
        vec[n].y = point->cur_u;

      if ( psh_point_is_strong( point ) )
        tags[n] |= (char)( ( dimension == 0 ) ? 32 : 64 );

#ifdef DEBUG_HINTER

      if ( dimension == 0 )
      {
        point->cur_x   = point->cur_u;
        point->flags_x = point->flags2 | point->flags;
      }
      else
      {
        point->cur_y   = point->cur_u;
        point->flags_y = point->flags2 | point->flags;
      }

#endif

      point++;
    }
  }

Project: savannah

  psh_hint_align( PSH_Hint     hint,
                  PSH_Globals  globals,
                  FT_Int       dimension,
                  PSH_Glyph    glyph )
  {
    PSH_Dimension  dim   = &globals->dimension[dimension];
    FT_Fixed       scale = dim->scale_mult;
    FT_Fixed       delta = dim->scale_delta;


    if ( !psh_hint_is_fitted( hint ) )
    {
      FT_Pos  pos = FT_MulFix( hint->org_pos, scale ) + delta;
      FT_Pos  len = FT_MulFix( hint->org_len, scale );

      FT_Int            do_snapping;
      FT_Pos            fit_len;
      PSH_AlignmentRec  align;


      /* ignore stem alignments when requested through the hint flags */
      if ( ( dimension == 0 && !glyph->do_horz_hints ) ||
           ( dimension == 1 && !glyph->do_vert_hints ) )
      {
        hint->cur_pos = pos;
        hint->cur_len = len;

        psh_hint_set_fitted( hint );
        return;
      }

      /* perform stem snapping when requested - this is necessary
       * for monochrome and LCD hinting modes only
       */
      do_snapping = ( dimension == 0 && glyph->do_horz_snapping ) ||
                    ( dimension == 1 && glyph->do_vert_snapping );

      hint->cur_len = fit_len = len;

      /* check blue zones for horizontal stems */
      align.align     = PSH_BLUE_ALIGN_NONE;
      align.align_bot = align.align_top = 0;

      if ( dimension == 1 )
        psh_blues_snap_stem( &globals->blues,
                             hint->org_pos + hint->org_len,
                             hint->org_pos,
                             &align );

      switch ( align.align )
      {
      case PSH_BLUE_ALIGN_TOP:
        /* the top of the stem is aligned against a blue zone */
        hint->cur_pos = align.align_top - fit_len;
        break;

      case PSH_BLUE_ALIGN_BOT:
        /* the bottom of the stem is aligned against a blue zone */
        hint->cur_pos = align.align_bot;
        break;

      case PSH_BLUE_ALIGN_TOP | PSH_BLUE_ALIGN_BOT:
        /* both edges of the stem are aligned against blue zones */
        hint->cur_pos = align.align_bot;
        hint->cur_len = align.align_top - align.align_bot;
        break;

      default:
        {
          PSH_Hint  parent = hint->parent;


          if ( parent )
          {
            FT_Pos  par_org_center, par_cur_center;
            FT_Pos  cur_org_center, cur_delta;


            /* ensure that parent is already fitted */
            if ( !psh_hint_is_fitted( parent ) )
              psh_hint_align( parent, globals, dimension, glyph );

            /* keep original relation between hints, this is, use the */
            /* scaled distance between the centers of the hints to    */
            /* compute the new position                               */
            par_org_center = parent->org_pos + ( parent->org_len >> 1 );
            par_cur_center = parent->cur_pos + ( parent->cur_len >> 1 );
            cur_org_center = hint->org_pos   + ( hint->org_len   >> 1 );

            cur_delta = FT_MulFix( cur_org_center - par_org_center, scale );
            pos       = par_cur_center + cur_delta - ( len >> 1 );
          }

          hint->cur_pos = pos;
          hint->cur_len = fit_len;

          /* Stem adjustment tries to snap stem widths to standard
           * ones.  This is important to prevent unpleasant rounding
           * artefacts.
           */
          if ( glyph->do_stem_adjust )
          {
            if ( len <= 64 )
            {
              /* the stem is less than one pixel; we will center it
               * around the nearest pixel center
               */
              if ( len >= 32 )
              {
                /* This is a special case where we also widen the stem
                 * and align it to the pixel grid.
                 *
                 *   stem_center          = pos + (len/2)
                 *   nearest_pixel_center = FT_ROUND(stem_center-32)+32
                 *   new_pos              = nearest_pixel_center-32
                 *                        = FT_ROUND(stem_center-32)
                 *                        = FT_FLOOR(stem_center-32+32)
                 *                        = FT_FLOOR(stem_center)
                 *   new_len              = 64
                 */
                pos = FT_PIX_FLOOR( pos + ( len >> 1 ) );
                len = 64;
              }
              else if ( len > 0 )
              {
                /* This is a very small stem; we simply align it to the
                 * pixel grid, trying to find the minimal displacement.
                 *
                 * left               = pos
                 * right              = pos + len
                 * left_nearest_edge  = ROUND(pos)
                 * right_nearest_edge = ROUND(right)
                 *
                 * if ( ABS(left_nearest_edge - left) <=
                 *      ABS(right_nearest_edge - right) )
                 *    new_pos = left
                 * else
                 *    new_pos = right
                 */
                FT_Pos  left_nearest  = FT_PIX_ROUND( pos );
                FT_Pos  right_nearest = FT_PIX_ROUND( pos + len );
                FT_Pos  left_disp     = left_nearest - pos;
                FT_Pos  right_disp    = right_nearest - ( pos + len );


                if ( left_disp < 0 )
                  left_disp = -left_disp;
                if ( right_disp < 0 )
                  right_disp = -right_disp;
                if ( left_disp <= right_disp )
                  pos = left_nearest;
                else
                  pos = right_nearest;
              }
              else
              {
                /* this is a ghost stem; we simply round it */
                pos = FT_PIX_ROUND( pos );
              }
            }
            else
            {
              len = psh_dimension_quantize_len( dim, len, 0 );
            }
          }

          /* now that we have a good hinted stem width, try to position */
          /* the stem along a pixel grid integer coordinate             */
          hint->cur_pos = pos + psh_hint_snap_stem_side_delta( pos, len );
          hint->cur_len = len;
        }
      }

      if ( do_snapping )
      {
        pos = hint->cur_pos;
        len = hint->cur_len;

        if ( len < 64 )
          len = 64;
        else
          len = FT_PIX_ROUND( len );

        switch ( align.align )
        {
          case PSH_BLUE_ALIGN_TOP:
            hint->cur_pos = align.align_top - len;
            hint->cur_len = len;
            break;

          case PSH_BLUE_ALIGN_BOT:
            hint->cur_len = len;
            break;

          case PSH_BLUE_ALIGN_BOT | PSH_BLUE_ALIGN_TOP:
            /* don't touch */
            break;


          default:
            hint->cur_len = len;
            if ( len & 64 )
              pos = FT_PIX_FLOOR( pos + ( len >> 1 ) ) + 32;
            else
              pos = FT_PIX_ROUND( pos + ( len >> 1 ) );

            hint->cur_pos = pos - ( len >> 1 );
            hint->cur_len = len;
        }
      }

      psh_hint_set_fitted( hint );

#ifdef DEBUG_HINTER
      if ( ps_debug_hint_func )
        ps_debug_hint_func( hint, dimension );
#endif
    }
  }

Project: savannah

  psh_hint_overlap( PSH_Hint  hint1,
                    PSH_Hint  hint2 )
  {
    return hint1->org_pos + hint1->org_len >= hint2->org_pos &&
           hint2->org_pos + hint2->org_len >= hint1->org_pos;
  }

Project: savannah

  psh_hint_snap_stem_side_delta( FT_Fixed  pos,
                                 FT_Fixed  len )
  {
    FT_Fixed  delta1 = FT_PIX_ROUND( pos ) - pos;
    FT_Fixed  delta2 = FT_PIX_ROUND( pos + len ) - pos - len;


    if ( FT_ABS( delta1 ) <= FT_ABS( delta2 ) )
      return delta1;
    else
      return delta2;
  }

Project: savannah

  psh_hint_table_activate_mask( PSH_Hint_Table  table,
                                PS_Mask         hint_mask )
  {
    FT_Int    mask = 0, val = 0;
    FT_Byte*  cursor = hint_mask->bytes;
    FT_UInt   idx, limit, count;


    limit = hint_mask->num_bits;
    count = 0;

    psh_hint_table_deactivate( table );

    for ( idx = 0; idx < limit; idx++ )
    {
      if ( mask == 0 )
      {
        val  = *cursor++;
        mask = 0x80;
      }

      if ( val & mask )
      {
        PSH_Hint  hint = &table->hints[idx];


        if ( !psh_hint_is_active( hint ) )
        {
          FT_UInt     count2;

#if 0
          PSH_Hint*  sort = table->sort;
          PSH_Hint   hint2;


          for ( count2 = count; count2 > 0; count2--, sort++ )
          {
            hint2 = sort[0];
            if ( psh_hint_overlap( hint, hint2 ) )
              FT_TRACE0(( "psh_hint_table_activate_mask:"
                          " found overlapping hints\n" ))
          }
#else
          count2 = 0;
#endif

          if ( count2 == 0 )
          {
            psh_hint_activate( hint );
            if ( count < table->max_hints )
              table->sort[count++] = hint;
            else
              FT_TRACE0(( "psh_hint_tableactivate_mask:"
                          " too many active hints\n" ));
          }
        }
      }

      mask >>= 1;
    }
    table->num_hints = count;

    /* now, sort the hints; they are guaranteed to not overlap */
    /* so we can compare their "org_pos" field directly        */
    {
      FT_Int     i1, i2;
      PSH_Hint   hint1, hint2;
      PSH_Hint*  sort = table->sort;


      /* a simple bubble sort will do, since in 99% of cases, the hints */
      /* will be already sorted -- and the sort will be linear          */
      for ( i1 = 1; i1 < (FT_Int)count; i1++ )
      {
        hint1 = sort[i1];
        for ( i2 = i1 - 1; i2 >= 0; i2-- )
        {
          hint2 = sort[i2];

          if ( hint2->org_pos < hint1->org_pos )
            break;

          sort[i2 + 1] = hint2;
          sort[i2]     = hint1;
        }
      }
    }
  }

Project: savannah

  psh_hint_table_align_hints( PSH_Hint_Table  table,
                              PSH_Globals     globals,
                              FT_Int          dimension,
                              PSH_Glyph       glyph )
  {
    PSH_Hint       hint;
    FT_UInt        count;

#ifdef DEBUG_HINTER

    PSH_Dimension  dim   = &globals->dimension[dimension];
    FT_Fixed       scale = dim->scale_mult;
    FT_Fixed       delta = dim->scale_delta;


    if ( ps_debug_no_vert_hints && dimension == 0 )
    {
      ps_simple_scale( table, scale, delta, dimension );
      return;
    }

    if ( ps_debug_no_horz_hints && dimension == 1 )
    {
      ps_simple_scale( table, scale, delta, dimension );
      return;
    }

#endif /* DEBUG_HINTER*/

    hint  = table->hints;
    count = table->max_hints;

    for ( ; count > 0; count--, hint++ )
      psh_hint_align( hint, globals, dimension, glyph );
  }

Project: savannah

  psh_hint_table_deactivate( PSH_Hint_Table  table )
  {
    FT_UInt   count = table->max_hints;
    PSH_Hint  hint  = table->hints;


    for ( ; count > 0; count--, hint++ )
    {
      psh_hint_deactivate( hint );
      hint->order = -1;
    }
  }

Project: savannah

  psh_hint_table_done( PSH_Hint_Table  table,
                       FT_Memory       memory )
  {
    FT_FREE( table->zones );
    table->num_zones = 0;
    table->zone      = 0;

    FT_FREE( table->sort );
    FT_FREE( table->hints );
    table->num_hints   = 0;
    table->max_hints   = 0;
    table->sort_global = 0;
  }

Project: savannah

  psh_hint_table_find_strong_points( PSH_Hint_Table  table,
                                     PSH_Point       point,
                                     FT_UInt         count,
                                     FT_Int          threshold,
                                     FT_Int          major_dir )
  {
    PSH_Hint*  sort      = table->sort;
    FT_UInt    num_hints = table->num_hints;


    for ( ; count > 0; count--, point++ )
    {
      FT_Int  point_dir = 0;
      FT_Pos  org_u     = point->org_u;


      if ( psh_point_is_strong( point ) )
        continue;

      if ( PSH_DIR_COMPARE( point->dir_in, major_dir ) )
        point_dir = point->dir_in;

      else if ( PSH_DIR_COMPARE( point->dir_out, major_dir ) )
        point_dir = point->dir_out;

      if ( point_dir )
      {
        if ( point_dir == major_dir )
        {
          FT_UInt  nn;


          for ( nn = 0; nn < num_hints; nn++ )
          {
            PSH_Hint  hint = sort[nn];
            FT_Pos    d    = org_u - hint->org_pos;


            if ( d < threshold && -d < threshold )
            {
              psh_point_set_strong( point );
              point->flags2 |= PSH_POINT_EDGE_MIN;
              point->hint    = hint;
              break;
            }
          }
        }
        else if ( point_dir == -major_dir )
        {
          FT_UInt  nn;


          for ( nn = 0; nn < num_hints; nn++ )
          {
            PSH_Hint  hint = sort[nn];
            FT_Pos    d    = org_u - hint->org_pos - hint->org_len;


            if ( d < threshold && -d < threshold )
            {
              psh_point_set_strong( point );
              point->flags2 |= PSH_POINT_EDGE_MAX;
              point->hint    = hint;
              break;
            }
          }
        }
      }

#if 1
      else if ( psh_point_is_extremum( point ) )
      {
        /* treat extrema as special cases for stem edge alignment */
        FT_UInt  nn, min_flag, max_flag;


        if ( major_dir == PSH_DIR_HORIZONTAL )
        {
          min_flag = PSH_POINT_POSITIVE;
          max_flag = PSH_POINT_NEGATIVE;
        }
        else
        {
          min_flag = PSH_POINT_NEGATIVE;
          max_flag = PSH_POINT_POSITIVE;
        }

        if ( point->flags2 & min_flag )
        {
          for ( nn = 0; nn < num_hints; nn++ )
          {
            PSH_Hint  hint = sort[nn];
            FT_Pos    d    = org_u - hint->org_pos;


            if ( d < threshold && -d < threshold )
            {
              point->flags2 |= PSH_POINT_EDGE_MIN;
              point->hint    = hint;
              psh_point_set_strong( point );
              break;
            }
          }
        }
        else if ( point->flags2 & max_flag )
        {
          for ( nn = 0; nn < num_hints; nn++ )
          {
            PSH_Hint  hint = sort[nn];
            FT_Pos    d    = org_u - hint->org_pos - hint->org_len;


            if ( d < threshold && -d < threshold )
            {
              point->flags2 |= PSH_POINT_EDGE_MAX;
              point->hint    = hint;
              psh_point_set_strong( point );
              break;
            }
          }
        }

        if ( point->hint == NULL )
        {
          for ( nn = 0; nn < num_hints; nn++ )
          {
            PSH_Hint  hint = sort[nn];


            if ( org_u >= hint->org_pos                 &&
                org_u <= hint->org_pos + hint->org_len )
            {
              point->hint = hint;
              break;
            }
          }
        }
      }

#endif /* 1 */
    }
  }

Project: savannah

  psh_hint_table_record( PSH_Hint_Table  table,
                         FT_UInt         idx )
  {
    PSH_Hint  hint = table->hints + idx;


    if ( idx >= table->max_hints )
    {
      FT_TRACE0(( "psh_hint_table_record: invalid hint index %d\n", idx ));
      return;
    }

    /* ignore active hints */
    if ( psh_hint_is_active( hint ) )
      return;

    psh_hint_activate( hint );

    /* now scan the current active hint set to check */
    /* whether `hint' overlaps with another hint     */
    {
      PSH_Hint*  sorted = table->sort_global;
      FT_UInt    count  = table->num_hints;
      PSH_Hint   hint2;


      hint->parent = 0;
      for ( ; count > 0; count--, sorted++ )
      {
        hint2 = sorted[0];

        if ( psh_hint_overlap( hint, hint2 ) )
        {
          hint->parent = hint2;
          break;
        }
      }
    }

    if ( table->num_hints < table->max_hints )
      table->sort_global[table->num_hints++] = hint;
    else
      FT_TRACE0(( "psh_hint_table_record: too many sorted hints!  BUG!\n" ));
  }

Project: savannah

  psh_hint_table_record_mask( PSH_Hint_Table  table,
                              PS_Mask         hint_mask )
  {
    FT_Int    mask = 0, val = 0;
    FT_Byte*  cursor = hint_mask->bytes;
    FT_UInt   idx, limit;


    limit = hint_mask->num_bits;

    for ( idx = 0; idx < limit; idx++ )
    {
      if ( mask == 0 )
      {
        val  = *cursor++;
        mask = 0x80;
      }

      if ( val & mask )
        psh_hint_table_record( table, idx );

      mask >>= 1;
    }
  }

Project: savannah

  psh_print_zone( PSH_Zone  zone )
  {
    printf( "zone [scale,delta,min,max] = [%.3f,%.3f,%d,%d]\n",
             zone->scale / 65536.0,
             zone->delta / 64.0,
             zone->min,
             zone->max );
  }