New optional ZONE arg for format-time-string etc.

This simplifies time conversions in other time zones.
It also prevents display-time-world tampering with TZ (Bug#21020).
* admin/admin.el (add-release-logs):
Use improved add-log-time-format API.
* admin/merge-gnulib (GNULIB_MODULES): Add time_rz, timegm.
(GNULIB_TOOL_FLAGS): Avoid flexmember, setenv, unsetenv.
* configure.ac (tzalloc): Remove test for this, since
Emacs no longer uses HAVE_TZALLOC directly.
* doc/lispref/os.texi (Time of Day, Time Conversion)
(Time Parsing):
* etc/NEWS: Document the new behavior.
Merge from gnulib, incorporating:
2015-07-25 strftime: fix newly-introduced bug on Solaris
2015-07-23 fprintftime, strftime: use timezone_t args
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/strftime.c, lib/strftime.h, lib/time.in.h, m4/sys_time_h.m4:
* m4/time_h.m4:
Update from gnulib.
* lib/time_rz.c, lib/timegm.c, m4/time_rz.m4, m4/timegm.m4:
New files from gnulib.
* lisp/time-stamp.el (time-stamp-string):
* lisp/time.el (display-time-world-list)
(display-time-world-display):
Use new API, with time zone arg.
* lisp/time.el (display-time-world-display):
Fix race when current-time advances while we're running.
* lisp/vc/add-log.el (add-log-iso8601-time-zone)
(add-log-iso8601-time-string): Accept optional time zone arg.
* lisp/vc/add-log.el (add-change-log-entry):
* lisp/vc/log-edit.el (log-edit-changelog-ours-p): Use new arg.
* nt/gnulib.mk: Propagate lib/gnulib.mk changes here.
Add rules for the time module, since they're now needed
for tzalloc etc.
* src/conf_post.h (getenv_TZ, setenv_TZ): New macros.
(emacs_getenv_TZ, emacs_setenv_TZ): New decls.
* src/editfns.c: Include errno.h.
(set_time_zone_rule): Omit unnecessary forward decl.
(initial_tz): Remove, replacing with ...
(local_tz, wall_clock_tz, utc_tz): New static vars and constants.
(tzeqlen): New constant; prefer it to (sizeof "TZ=" - 1).
(emacs_localtime_rz, emacs_mktime_z, xtzalloc, xtzfree)
(tzlookup): New static functions.
(init_editfns): New arg DUMPING.  All uses changed.
(init_editfns): Omit most initialization if dumping, not if
!initialized.  Initialize wall_clock_tz and local_tz.
(emacs_nmemftime, format_time_string): Time zone argument can now
be any time zone, not just a boolean for UTC or local time.  All
callers changed.
(Fformat_time_string, Fencode_time, Fcurrent_time_string)
(Fcurrent_time_zone): New optional arg ZONE.
(Fdecode_time, Fset_time_zone_rule): ZONE arg can now also take
the same form as with the other new additions.
(decode_time_zone): Remove; no longer needed.
(tzvalbuf): Now file-scope.
(emacs_getenv_TZ, emacs_setenv_TZ): New functions.
(syms_of_editfns): Define Qwall.
* src/editfns.c (mktime_z) [!HAVE_TZALLOC]:
* src/systime.h (mktime_z, timezone_t, tzalloc, tzfree)
[!HAVE_TZALLOC]:
Remove; now supplied by gnulib.
* src/emacs.c (main):
* src/lisp.h (init_editfns): Adjust to init_editfns API change.

1 files changed, 17 insertions, 47 deletions

diff --git a/lib/strftime.c b/lib/strftime.c
index 2426aae7052..c7cec2621c9 100644
--- a/lib/strftime.c
+++ b/lib/strftime.c
@@ -121,22 +121,11 @@ extern char *tzname[];
 
 
 #ifdef _LIBC
+# define mktime_z(tz, tm) mktime (tm)
 # define tzname __tzname
 # define tzset __tzset
 #endif
 
-#if !HAVE_TM_GMTOFF
-/* Portable standalone applications should supply a "time.h" that
-   declares a POSIX-compliant localtime_r, for the benefit of older
-   implementations that lack localtime_r or have a nonstandard one.
-   See the gnulib time_r module for one way to implement this.  */
-# undef __gmtime_r
-# undef __localtime_r
-# define __gmtime_r gmtime_r
-# define __localtime_r localtime_r
-#endif
-
-
 #ifndef FPRINTFTIME
 # define FPRINTFTIME 0
 #endif
@@ -385,12 +374,7 @@ iso_week_days (int yday, int wday)
 
 /* When compiling this file, GNU applications can #define my_strftime
    to a symbol (typically nstrftime) to get an extended strftime with
-   extra arguments UT and NS.  Emacs is a special case for now, but
-   this Emacs-specific code can be removed once Emacs's config.h
-   defines my_strftime.  */
-#if defined emacs && !defined my_strftime
-# define my_strftime nstrftime
-#endif
+   extra arguments TZ and NS.  */
 
 #if FPRINTFTIME
 # undef my_strftime
@@ -398,8 +382,9 @@ iso_week_days (int yday, int wday)
 #endif
 
 #ifdef my_strftime
-# define extra_args , ut, ns
-# define extra_args_spec , int ut, int ns
+# undef HAVE_TZSET
+# define extra_args , tz, ns
+# define extra_args_spec , timezone_t tz, int ns
 #else
 # if defined COMPILE_WIDE
 #  define my_strftime wcsftime
@@ -411,7 +396,7 @@ iso_week_days (int yday, int wday)
 # define extra_args
 # define extra_args_spec
 /* We don't have this information in general.  */
-# define ut 0
+# define tz 1
 # define ns 0
 #endif
 
@@ -483,7 +468,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
   zone = (const char *) tp->tm_zone;
 #endif
 #if HAVE_TZNAME
-  if (ut)
+  if (!tz)
     {
       if (! (zone && *zone))
         zone = "GMT";
@@ -496,7 +481,12 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
       tzset ();
 # endif
     }
+  /* The tzset() call might have changed the value.  */
+  if (!(zone && *zone) && tp->tm_isdst >= 0)
+    zone = tzname[tp->tm_isdst != 0];
 #endif
+  if (! zone)
+    zone = "";
 
   if (hour12 > 12)
     hour12 -= 12;
@@ -1144,7 +1134,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
             time_t t;
 
             ltm = *tp;
-            t = mktime (&ltm);
+            t = mktime_z (tz, &ltm);
 
             /* Generate string value for T using time_t arithmetic;
                this works even if sizeof (long) < sizeof (time_t).  */
@@ -1319,14 +1309,6 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
               to_lowcase = true;
             }
 
-#if HAVE_TZNAME
-          /* The tzset() call might have changed the value.  */
-          if (!(zone && *zone) && tp->tm_isdst >= 0)
-            zone = tzname[tp->tm_isdst != 0];
-#endif
-          if (! zone)
-            zone = "";
-
 #ifdef COMPILE_WIDE
           {
             /* The zone string is always given in multibyte form.  We have
@@ -1366,7 +1348,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
 #if HAVE_TM_GMTOFF
             diff = tp->tm_gmtoff;
 #else
-            if (ut)
+            if (!tz)
               diff = 0;
             else
               {
@@ -1375,7 +1357,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
                 time_t lt;
 
                 ltm = *tp;
-                lt = mktime (&ltm);
+                lt = mktime_z (tz, &ltm);
 
                 if (lt == (time_t) -1)
                   {
@@ -1384,7 +1366,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
                        occurred.  */
                     struct tm tm;
 
-                    if (! __localtime_r (&lt, &tm)
+                    if (! localtime_rz (tz, &lt, &tm)
                         || ((ltm.tm_sec ^ tm.tm_sec)
                             | (ltm.tm_min ^ tm.tm_min)
                             | (ltm.tm_hour ^ tm.tm_hour)
@@ -1394,7 +1376,7 @@ strftime_case_ (bool upcase, STREAM_OR_CHAR_T *s,
                       break;
                   }
 
-                if (! __gmtime_r (&lt, &gtm))
+                if (! localtime_rz (0, &lt, &gtm))
                   break;
 
                 diff = tm_diff (&ltm, &gtm);
@@ -1473,15 +1455,3 @@ my_strftime (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)
 #if defined _LIBC && ! FPRINTFTIME
 libc_hidden_def (my_strftime)
 #endif
-
-
-#if defined emacs && ! FPRINTFTIME
-/* For Emacs we have a separate interface which corresponds to the normal
-   strftime function plus the ut argument, but without the ns argument.  */
-size_t
-emacs_strftimeu (char *s, size_t maxsize, const char *format,
-                 const struct tm *tp, int ut)
-{
-  return my_strftime (s, maxsize, format, tp, ut, 0);
-}
-#endif