Improve time stamp handling, and be more consistent about it.

This implements a suggestion made in:
http://lists.gnu.org/archive/html/emacs-devel/2014-10/msg00587.html
Among other things, this means timer.el no longer needs to
autoload the time-date module.
* doc/lispref/os.texi (Time of Day, Time Conversion, Time Parsing)
(Processor Run Time, Time Calculations):
Document the new behavior, plus be clearer about the old behavior.
(Idle Timers): Take advantage of new functionality.
* etc/NEWS: Document the changes.
* lisp/allout-widgets.el (allout-elapsed-time-seconds): Doc fix.
* lisp/arc-mode.el (archive-ar-summarize):
* lisp/calendar/time-date.el (seconds-to-time, days-to-time, time-since):
* lisp/emacs-lisp/timer.el (timer-relative-time, timer-event-handler)
(run-at-time, with-timeout-suspend, with-timeout-unsuspend):
* lisp/net/tramp.el (tramp-time-less-p, tramp-time-subtract):
* lisp/proced.el (proced-time-lessp):
* lisp/timezone.el (timezone-time-from-absolute):
* lisp/type-break.el (type-break-schedule, type-break-time-sum):
Simplify by using new functionality.
* lisp/calendar/cal-dst.el (calendar-next-time-zone-transition):
Do not return time values in obsolete and undocumented (HI . LO)
format; use (HI LO) instead.
* lisp/calendar/time-date.el (with-decoded-time-value):
Treat 'nil' as current time.  This is mostly for XEmacs.
(encode-time-value, with-decoded-time-value): Obsolete.
(time-add, time-subtract, time-less-p): Use no-op autoloads, for
XEmacs.  Define only if XEmacs, as they're now C builtins in Emacs.
* lisp/ldefs-boot.el: Update to match new time-date.el
* lisp/proced.el: Do not require time-date.
* src/editfns.c (invalid_time): New function.
Use it instead of 'error ("Invalid time specification")'.
(time_add, time_subtract, time_arith, Ftime_add, Ftime_less_p)
(decode_float_time, lisp_to_timespec, lisp_time_struct):
New functions.
(make_time_tail, make_time): Remove.  All uses changed to use
new functions or plain list4i.
(disassemble_lisp_time): Return effective length if successful.
Check that LOW is an integer, if it's combined with other components.
(decode_time_components): Decode into struct lisp_time, not
struct timespec, so that we can support a wide set of times
regardless of whether time_t is signed.  Decode plain numbers
as seconds since the Epoch, and nil as the current time.
(lisp_time_argument, lisp_seconds_argument, Ffloat_time):
Reimplement in terms of new functions.
(Fencode_time): Just use list2i.
(syms_of_editfns): Add time-add, time-subtract, time-less-p.
* src/keyboard.c (decode_timer): Don't allow the new formats (floating
point or nil) in timers.
* src/systime.h (LO_TIME_BITS): New constant.  Use it everywhere in
place of the magic number '16'.
(struct lisp_time): New type.
(decode_time_components): Use it.
(lisp_to_timespec): New decl.

1 files changed, 4 insertions, 13 deletions

diff --git a/lisp/type-break.el b/lisp/type-break.el
index f954e5d1c26..a3af407bf17 100644
--- a/lisp/type-break.el
+++ b/lisp/type-break.el
@@ -604,8 +604,7 @@ INTERVAL is the full length of an interval (defaults to TIME)."
   (type-break-time-warning-schedule time 'reset)
   (type-break-run-at-time (max 1 time) nil 'type-break-alarm)
   (setq type-break-time-next-break
-        (type-break-time-sum (or start (current-time))
-                             (or interval time))))
+        (type-break-time-sum start (or interval time))))
 
 (defun type-break-cancel-schedule ()
   (type-break-cancel-time-warning-schedule)
@@ -961,19 +960,11 @@ FRAC should be the inverse of the fractional value; for example, a value of
 (defun type-break-time-difference (a b)
   (round (float-time (time-subtract b a))))
 
-;; Return (in a new list the same in structure to that returned by
-;; `current-time') the sum of the arguments.  Each argument may be a time
-;; list or a single integer, a number of seconds.
-;; This function keeps the high and low 16 bits of the seconds properly
-;; balanced so that the lower value never exceeds 16 bits.  Otherwise, when
-;; the result is passed to `current-time-string' it will toss some of the
-;; "low" bits and format the time incorrectly.
+;; Return a time value that is the sum of the time-value arguments.
 (defun type-break-time-sum (&rest tmlist)
-  (let ((sum '(0 0 0)))
+  (let ((sum '(0 0)))
     (dolist (tem tmlist)
-      (setq sum (time-add sum (if (integerp tem)
-				  (list (floor tem 65536) (mod tem 65536))
-				tem))))
+      (setq sum (time-add sum tem)))
     sum))
 
 (defun type-break-time-stamp (&optional when)