Avoid signed integer overflow when converting Time to ptrdiff_t.

* keyboard.c (INPUT_EVENT_POS_MAX, INPUT_EVENT_POS_MIN):
New macros.
(position_to_Time, Time_to_position): New functions.
(gen_help_event, kbd_buffer_get_event): Use them.
* systime.h (Time) [emacs && !HAVE_X_WINDOWS]:
Go back to plain 'unsigned long', so that 'Time' is the same
for both X and non-X builds; this is less likely to cause surprise.
* termhooks.h: Remove compile-time check that Time and ptrdiff_t
are the same size; this is no longer required.

1 files changed, 0 insertions, 3 deletions

diff --git a/src/termhooks.h b/src/termhooks.h
index 6412f0da6ca..8d85fba8af8 100644
--- a/src/termhooks.h
+++ b/src/termhooks.h
@@ -288,9 +288,6 @@ struct input_event
   Lisp_Object arg;
 };
 
-/* To make sure we don't break HELP_EVENT.  */
-verify (sizeof (Time) == sizeof (ptrdiff_t));
-
 #define EVENT_INIT(event) memset (&(event), 0, sizeof (struct input_event))
 
 /* Bits in the modifiers member of the input_event structure.