Check for overflow when converting integer to cons and back.

* charset.c (Fdefine_charset_internal, Fdecode_char):
Use cons_to_unsigned to catch overflow.
(Fencode_char): Use INTEGER_TO_CONS.
* composite.h (LGLYPH_CODE): Use cons_to_unsigned.
(LGLYPH_SET_CODE): Use INTEGER_TO_CONS.
* data.c (long_to_cons, cons_to_long): Remove.
(cons_to_unsigned, cons_to_signed): New functions.
These signal an error for invalid or out-of-range values.
* dired.c (Ffile_attributes): Use INTEGER_TO_CONS.
* fileio.c (Fset_visited_file_modtime): Use CONS_TO_INTEGER.
* font.c (Ffont_variation_glyphs):
* fontset.c (Finternal_char_font): Use INTEGER_TO_CONS.
* lisp.h: Include <intprops.h>.
(INTEGER_TO_CONS, CONS_TO_INTEGER): New macros.
(cons_to_signed, cons_to_unsigned): New decls.
(long_to_cons, cons_to_long): Remove decls.
* undo.c (record_first_change): Use INTEGER_TO_CONS.
(Fprimitive_undo): Use CONS_TO_INTEGER.
* xfns.c (Fx_window_property): Likewise.
* xselect.c: Include <limits.h>.
(x_own_selection, selection_data_to_lisp_data):
Use INTEGER_TO_CONS.
(x_handle_selection_request, x_handle_selection_clear)
(x_get_foreign_selection, Fx_disown_selection_internal)
(Fx_get_atom_name, x_send_client_event): Use CONS_TO_INTEGER.
(lisp_data_to_selection_data): Use cons_to_unsigned.
(x_fill_property_data): Use cons_to_signed.
Report values out of range.

1 files changed, 5 insertions, 10 deletions

diff --git a/src/undo.c b/src/undo.c
index 142960545a7..e7e9ae5632e 100644
--- a/src/undo.c
+++ b/src/undo.c
@@ -212,7 +212,6 @@ record_change (EMACS_INT beg, EMACS_INT length)
 void
 record_first_change (void)
 {
-  Lisp_Object high, low;
   struct buffer *base_buffer = current_buffer;
 
   if (EQ (BVAR (current_buffer, undo_list), Qt))
@@ -225,9 +224,9 @@ record_first_change (void)
   if (base_buffer->base_buffer)
     base_buffer = base_buffer->base_buffer;
 
-  XSETFASTINT (high, (base_buffer->modtime >> 16) & 0xffff);
-  XSETFASTINT (low, base_buffer->modtime & 0xffff);
-  BVAR (current_buffer, undo_list) = Fcons (Fcons (Qt, Fcons (high, low)), BVAR (current_buffer, undo_list));
+  BVAR (current_buffer, undo_list) =
+    Fcons (Fcons (Qt, INTEGER_TO_CONS (base_buffer->modtime)),
+           BVAR (current_buffer, undo_list));
 }
 
 /* Record a change in property PROP (whose old value was VAL)
@@ -499,13 +498,9 @@ Return what remains of the list.  */)
               if (EQ (car, Qt))
                 {
                   /* Element (t high . low) records previous modtime.  */
-                  Lisp_Object high, low;
-                  time_t mod_time;
                   struct buffer *base_buffer = current_buffer;
-
-                  high = Fcar (cdr);
-                  low = Fcdr (cdr);
-                  mod_time = (XFASTINT (high) << 16) + XFASTINT (low);
+                  time_t mod_time;
+                  CONS_TO_INTEGER (cdr, time_t, mod_time);
 
                   if (current_buffer->base_buffer)
                     base_buffer = current_buffer->base_buffer;