From b54c03bb04d73f96189965e1d326710a20f88272 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Wed, 4 Nov 2015 16:45:44 -0700
Subject: [PATCH] refine Cairo patch for CTFontCreatePathForGlyph

The CTFontCreatePathForGlyph() function can return NULL when
the glyph exists but has an empty path. Instead of treating that
as failure, which causes Cairo to generate a bitmap version of
the glyph, check that the glyph is mapped for bounding boxes,
and treat a NULL path as an empty path in that case.
---
 .../native-libs/patches/cgfontgetglyph.patch  | 40 ++++++++++++++++---
 1 file changed, 34 insertions(+), 6 deletions(-)

diff --git a/racket/src/native-libs/patches/cgfontgetglyph.patch b/racket/src/native-libs/patches/cgfontgetglyph.patch
index bde65a327e..c936bb52f4 100644
--- a/racket/src/native-libs/patches/cgfontgetglyph.patch
+++ b/racket/src/native-libs/patches/cgfontgetglyph.patch
@@ -1,6 +1,6 @@
-diff -u -r old/cairo-1.12.16/src/cairo-quartz-font.c new/cairo-1.12.16/src/cairo-quartz-font.c
---- old/cairo-1.12.16/src/cairo-quartz-font.c	2015-09-06 17:07:39.000000000 -0600
-+++ new/cairo-1.12.16/src/cairo-quartz-font.c	2015-09-06 17:09:06.000000000 -0600
+diff -r -u old/cairo-1.12.16/src/cairo-quartz-font.c new/cairo-1.12.16/src/cairo-quartz-font.c
+--- old/cairo-1.12.16/src/cairo-quartz-font.c	2015-11-04 15:21:19.000000000 -0700
++++ new/cairo-1.12.16/src/cairo-quartz-font.c	2015-11-04 15:21:37.000000000 -0700
 @@ -81,9 +81,6 @@
  static void (*CGContextSetAllowsFontSmoothingPtr) (CGContextRef, bool) = NULL;
  static bool (*CGContextGetAllowsFontSmoothingPtr) (CGContextRef) = NULL;
@@ -27,22 +27,50 @@ diff -u -r old/cairo-1.12.16/src/cairo-quartz-font.c new/cairo-1.12.16/src/cairo
  	(CGFontGetHMetricsPtr || (CGFontGetAscentPtr && CGFontGetDescentPtr && CGFontGetLeadingPtr)))
  	_cairo_quartz_font_symbols_present = TRUE;
  
-@@ -592,6 +587,7 @@
+@@ -592,6 +587,8 @@
      CGGlyph glyph = _cairo_quartz_scaled_glyph_index (scaled_glyph);
      CGAffineTransform textMatrix;
      CGPathRef glyphPath;
 +    CTFontRef ctFont;
++    int empty_path;
      cairo_path_fixed_t *path;
  
      if (glyph == INVALID_GLYPH) {
-@@ -606,7 +602,9 @@
+@@ -606,19 +603,32 @@
  					-font->base.scale.yy,
  					0, 0);
  
 -    glyphPath = CGFontGetGlyphPathPtr (font_face->cgFont, &textMatrix, 0, glyph);
+-    if (!glyphPath)
 +    ctFont = CTFontCreateWithGraphicsFont (font_face->cgFont, 1.0, NULL, NULL);
 +    glyphPath = CTFontCreatePathForGlyph (ctFont, glyph, &textMatrix);
++    empty_path = 0;
++    if (!glyphPath) {
++	/* an empty glyph path may just reflect whitespace; check bounding rects */
++	CGRect r;
++	r = CTFontGetBoundingRectsForGlyphs(ctFont, kCTFontHorizontalOrientation, &glyph, NULL, 1);
++	if (memcmp(&CGRectNull, &r, sizeof(CGRect)))
++	    empty_path = 1;
++    }
 +    CFRelease (ctFont);
-     if (!glyphPath)
++    if (!glyphPath && !empty_path)
  	return CAIRO_INT_STATUS_UNSUPPORTED;
  
+     path = _cairo_path_fixed_create ();
+     if (!path) {
+-	CGPathRelease (glyphPath);
++	if (glyphPath)
++	    CGPathRelease (glyphPath);
+ 	return _cairo_error(CAIRO_STATUS_NO_MEMORY);
+     }
+ 
+-    CGPathApply (glyphPath, path, _cairo_quartz_path_apply_func);
++    if (glyphPath)
++	CGPathApply (glyphPath, path, _cairo_quartz_path_apply_func);
+ 
+-    CGPathRelease (glyphPath);
++    if (glyphPath) 
++	CGPathRelease (glyphPath);
+ 
+     _cairo_scaled_glyph_set_path (scaled_glyph, &font->base, path);
+