(GET_OVERLAYS_AT): New macro.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/buffer.h b/src/buffer.h
index e2205a916e6..b5227cb9981 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -823,6 +823,25 @@ extern void buffer_slot_type_mismatch P_ ((int));
 extern void fix_overlays_before P_ ((struct buffer *, EMACS_INT, EMACS_INT));
 extern void mmap_set_vars P_ ((int));
 
+/* Get overlays at POSN into array OVERLAYS with NOVERLAYS elements.
+   If NEXTP is non-NULL, return next overlay there.
+   See overlay_at arg CHANGE_REQ for meaning of CHRQ arg.  */
+
+#define GET_OVERLAYS_AT(posn, overlays, noverlays, nextp, chrq)         \
+  do {                                                                  \
+    int maxlen = 40;                                                    \
+    overlays = (Lisp_Object *) alloca (maxlen * sizeof (Lisp_Object));  \
+    noverlays = overlays_at (posn, 0, &overlays, &maxlen,               \
+                             nextp, NULL, chrq);                                \
+    if (noverlays > maxlen)                                             \
+      {                                                                 \
+        maxlen = noverlays;                                             \
+        overlays = (Lisp_Object *) alloca (maxlen * sizeof (Lisp_Object)); \
+        noverlays = overlays_at (posn, 0, &overlays, &maxlen,           \
+                                 nextp, NULL, chrq);                    \
+      }                                                                 \
+  } while (0)
+
 EXFUN (Fbuffer_name, 1);
 EXFUN (Fget_file_buffer, 1);
 EXFUN (Fnext_overlay_change, 1);