From 6adaeec2a5681bb290a3a70968952780146abf66 Mon Sep 17 00:00:00 2001 From: Federico Tedin Date: Sun, 3 May 2020 15:47:56 +0200 Subject: [PATCH] Prevent hanging in next-single-char-property-change * src/textprop.c (Fnext_single_char_property_change): Clarify in the doc string the behavior when LIMIT is past the end of OBJECT. Stop the search when position gets to end of buffer, for when LIMIT is beyond that. (Bug#40000) --- src/textprop.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/src/textprop.c b/src/textprop.c index 960dba3f8d..0876badc87 100644 --- a/src/textprop.c +++ b/src/textprop.c @@ -766,14 +766,13 @@ DEFUN ("next-single-char-property-change", Fnext_single_char_property_change, If OBJECT is a string, POSITION is a 0-based index into it. In a string, scan runs to the end of the string, unless LIMIT is non-nil. -In a buffer, if LIMIT is nil or omitted, it runs to (point-max), and the -value cannot exceed that. +In a buffer, scan runs to end of buffer, unless LIMIT is non-nil. If the optional fourth argument LIMIT is non-nil, don't search past position LIMIT; return LIMIT if nothing is found before LIMIT. +However, if OBJECT is a buffer and LIMIT is beyond the end of the +buffer, this function returns `point-max', not LIMIT. -The property values are compared with `eq'. -If the property is constant all the way to the end of OBJECT, return the -last valid position in OBJECT. */) +The property values are compared with `eq'. */) (Lisp_Object position, Lisp_Object prop, Lisp_Object object, Lisp_Object limit) { if (STRINGP (object)) @@ -832,6 +831,9 @@ DEFUN ("next-single-char-property-change", Fnext_single_char_property_change, value = Fget_char_property (position, prop, object); if (!EQ (value, initial_value)) break; + + if (XFIXNAT (position) >= ZV) + break; } position = unbind_to (count, position); -- 2.17.1