master 0fe8ab7: Avoid segfaults in lookup_image when faces were freed

[Eli Zaretskii]

branch: master
commit 0fe8ab79e7a2306b84e209cc4e90da1996da1cad
Author: Eli Zaretskii <eliz@gnu.org>
Commit: Eli Zaretskii <eliz@gnu.org>

    Avoid segfaults in lookup_image when faces were freed
    
    * src/image.c (lookup_image): Make sure the frame's face cache
    exists and has at least the basic faces.  If FACE_ID is not a
    basic face, and is no longer cached, fall back on the 'default'
    face.  (Bug#43700)
---
 src/image.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/src/image.c b/src/image.c
index 6ecf6a7..25d5af8 100644
--- a/src/image.c
+++ b/src/image.c
@@ -2329,8 +2329,14 @@ lookup_image (struct frame *f, Lisp_Object spec, int 
face_id)
   struct image *img;
   EMACS_UINT hash;
 
-  struct face *face = (face_id >= 0) ? FACE_FROM_ID (f, face_id)
-    : FACE_FROM_ID (f, DEFAULT_FACE_ID);
+  if (FRAME_FACE_CACHE (f) == NULL)
+    init_frame_faces (f);
+  if (FRAME_FACE_CACHE (f)->used == 0)
+    recompute_basic_faces (f);
+  if (face_id < 0 || face_id >= FRAME_FACE_CACHE (f)->used)
+    face_id = DEFAULT_FACE_ID;
+
+  struct face *face = FACE_FROM_ID (f, face_id);
   unsigned long foreground = FACE_COLOR_TO_PIXEL (face->foreground, f);
   unsigned long background = FACE_COLOR_TO_PIXEL (face->background, f);