[cairo-commit] src/cairo-xlib-surface.c

[Chris Wilson]

 src/cairo-xlib-surface.c |   38 +++++++++++++++++++++++++++++---------
 1 file changed, 29 insertions(+), 9 deletions(-)

New commits:
commit 6ee216000ae487492fceda0fb3fecb20bb9a41f6
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Thu Sep 13 15:25:49 2012 +0100

    xlib: Explicitly discard the fallback shm pixmap upon user modification
    
    If the user changes the size of the underlying drawable, we much make
    sure that we discard the current ShmPixmap in order to create a new
    fallback pixmap of the correct size next time.
    
    Reported-by: Weng Xuetian <wengxt at gmail.com>
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/cairo-xlib-surface.c b/src/cairo-xlib-surface.c
index 913589f..4d1ef90 100644
--- a/src/cairo-xlib-surface.c
+++ b/src/cairo-xlib-surface.c
@@ -358,6 +358,22 @@ _cairo_xlib_surface_create_similar (void	       *abstract_src,
     return &surface->base;
 }
 
+static void
+_cairo_xlib_surface_discard_shm (cairo_xlib_surface_t *surface)
+{
+    if (surface->shm == NULL)
+	return;
+
+    /* Force the flush for an external surface */
+    if (!surface->owns_pixmap)
+	cairo_surface_flush (surface->shm);
+
+    cairo_surface_finish (surface->shm);
+    cairo_surface_destroy (surface->shm);
+
+    surface->shm = NULL;
+}
+
 static cairo_status_t
 _cairo_xlib_surface_finish (void *abstract_surface)
 {
@@ -378,13 +394,7 @@ _cairo_xlib_surface_finish (void *abstract_surface)
     if (surface->picture)
 	XRenderFreePicture (display->display, surface->picture);
 
-    if (surface->shm) {
-	/* Force the flush for an external surface */
-	if (!surface->owns_pixmap)
-	    cairo_surface_flush (surface->shm);
-	cairo_surface_finish (surface->shm);
-	cairo_surface_destroy (surface->shm);
-    }
+    _cairo_xlib_surface_discard_shm (surface);
 
     if (surface->owns_pixmap)
 	XFreePixmap (display->display, surface->drawable);
@@ -2048,6 +2058,9 @@ cairo_xlib_surface_set_size (cairo_surface_t *abstract_surface,
 	return;
     }
 
+    if (surface->width == width && surface->height == height)
+	return;
+
     if (! valid_size (width, height)) {
 	_cairo_surface_set_error (abstract_surface,
 				  _cairo_error (CAIRO_STATUS_INVALID_SIZE));
@@ -2060,9 +2073,12 @@ cairo_xlib_surface_set_size (cairo_surface_t *abstract_surface,
 	return;
     }
 
+    _cairo_xlib_surface_discard_shm (surface);
+
     surface->width = width;
     surface->height = height;
 }
+
 /**
  * cairo_xlib_surface_set_drawable:
  * @surface: a #cairo_surface_t for the XLib backend
@@ -2142,8 +2158,12 @@ cairo_xlib_surface_set_drawable (cairo_surface_t   *abstract_surface,
 	surface->drawable = drawable;
     }
 
-    surface->width = width;
-    surface->height = height;
+    if (surface->width != width || surface->height != height) {
+	_cairo_xlib_surface_discard_shm (surface);
+
+	surface->width = width;
+	surface->height = height;
+    }
 }
 
 /**