From 849322235764f570a4a3a1217960d096d16165cf Mon Sep 17 00:00:00 2001
From: Carl Worth <cworth@cworth.org>
Date: Tue, 29 Jan 2008 05:40:39 -0800
Subject: [PATCH] Initialize return values for cairo_*_extents in case of error

Previously we left the return values alone, which set the
user up for a nasty trap, (using potentially uninitialized
values with no indication that there was an error). So now
we initialize these values to 0.0 if the cairo_t is in error.

The fixed functions include:

	cairo_path_extents
	cairo_stroke_extents
	cairo_fill_extents
	cairo_clip_extents
	cairo_font_extents
---
 src/cairo.c | 54 +++++++++++++++++++++++++++++++++++++++++++++++++----
 1 file changed, 50 insertions(+), 4 deletions(-)

diff --git a/src/cairo.c b/src/cairo.c
index d3c5ba481..b047d9935 100644
--- a/src/cairo.c
+++ b/src/cairo.c
@@ -1904,8 +1904,18 @@ void
 cairo_path_extents (cairo_t *cr,
 		    double *x1, double *y1, double *x2, double *y2)
 {
-    if (cr->status)
+    if (cr->status) {
+	if (x1)
+	    *x1 = 0.0;
+	if (y1)
+	    *y1 = 0.0;
+	if (x2)
+	    *x2 = 0.0;
+	if (y2)
+	    *y2 = 0.0;
+
 	return;
+    }
 
     _cairo_gstate_path_extents (cr->gstate,
 				cr->path,
@@ -2301,8 +2311,18 @@ cairo_stroke_extents (cairo_t *cr,
 {
     cairo_status_t status;
 
-    if (cr->status)
+    if (cr->status) {
+	if (x1)
+	    *x1 = 0.0;
+	if (y1)
+	    *y1 = 0.0;
+	if (x2)
+	    *x2 = 0.0;
+	if (y2)
+	    *y2 = 0.0;
+
 	return;
+    }
 
     status = _cairo_gstate_stroke_extents (cr->gstate,
 					   cr->path,
@@ -2337,8 +2357,18 @@ cairo_fill_extents (cairo_t *cr,
 {
     cairo_status_t status;
 
-    if (cr->status)
+    if (cr->status) {
+	if (x1)
+	    *x1 = 0.0;
+	if (y1)
+	    *y1 = 0.0;
+	if (x2)
+	    *x2 = 0.0;
+	if (y2)
+	    *y2 = 0.0;
+
 	return;
+    }
 
     status = _cairo_gstate_fill_extents (cr->gstate,
 					 cr->path,
@@ -2462,8 +2492,18 @@ cairo_clip_extents (cairo_t *cr,
 {
     cairo_status_t status;
 
-    if (cr->status)
+    if (cr->status) {
+	if (x1)
+	    *x1 = 0.0;
+	if (y1)
+	    *y1 = 0.0;
+	if (x2)
+	    *x2 = 0.0;
+	if (y2)
+	    *y2 = 0.0;
+
 	return;
+    }
 
     status = _cairo_gstate_clip_extents (cr->gstate, x1, y1, x2, y2);
     if (status)
@@ -2561,6 +2601,12 @@ cairo_font_extents (cairo_t              *cr,
 {
     cairo_status_t status;
 
+    extents->ascent = 0.0;
+    extents->descent = 0.0;
+    extents->height = 0.0;
+    extents->max_x_advance = 0.0;
+    extents->max_y_advance = 0.0;
+
     if (cr->status)
 	return;