zoneinfo: also install tzdata.zi and version

[philip]

Summary

Build and install the shrunk version of the time zone database required
by libc++ 19 std::chrono::current_zone (etc). While here, also install
the tzdata 'version' file to align more closely with other vendors.

PR: 282377

[philip]

This builds the "main" format of the time zone database. That includes backward compatibility links but it doesn't include historical ("backzone") data. The "redo" bit controls how leapseconds are handled. We may want this to be posix_right. I'm not sure what other vendors do here.

[emaste]

LGTM. We can address leap seconds etc. after commit.

[dim]

Great, thanks.

[imp]

Setting it to posix_right i think is a terrible idea as the default. One that should be carefully considered in the larger backdrop. Iirc, being able to opt into posix_right can be good for some applications, but switching the default is HUGE pola and requires a systemic review for far too many use cases, many of which won't be known untils years later. Anybody using smeared leap seconds won't want it, for example. There's two, completely irreconcilable warring factions and way stronger evidence than just what other vendors are doing is going to be needed since there's about a 40s difference in what you set the system time to for starters... it shouldn't be done in phab.

There's talk of ditching leaps entirely and its unclear if we will have another one too.. .

[philip]

Thanks for the feedback. That was my reasoning for doing posix_only instead of the tzdata default posix_right.

It sounds like it's currently not worth the bother of doing a build knob for changing this.

I'll put this in main as-is. I don't currently have a plan to merge this to stable. The earliest I would merge it is after a future tzdata release in the second half of this year or so. While there are no current consumers of this, this will want a long time to soak if libc++ picks it up.

share/zoneinfo/Makefile

 --- Makefile.in.orig    2015-09-12 19:49:17 UTC
 +++ Makefile.in
 @@ -1415,7 +1415,7 @@ printdeps:
  # This is kind of a hack, but I couldn't find a better way to adjust the paths
  # in the script before it gets installed...
  install-exec-hook:
 -       script=tsdb; pkgdatadir='$(pkgdatadir)'; configdir='$(pkgdatadir)/etc/opentsdb'; \
-+       script=tsdb; pkgdatadir='$(pkgdatadir)'; configdir='/usr/local/etc/opentsdb'; \
++       script=tsdb; pkgdatadir='$(pkgdatadir)'; configdir='$(sysconfdir)/etc/opentsdb'; \
            abs_srcdir=''; abs_builddir=''; $(edit_tsdb_script)
         cat tsdb.tmp >"$(DESTDIR)$(bindir)/tsdb"
         rm -f tsdb.tmp
+@@ -1442,7 +1442,7 @@ gwtc: .gwtc-stamp
+        @$(mkdir_p) gwt
+        { cd $(srcdir) && cat $(httpui_SRC); } | $(MD5) >"$@-t"
+        cmp -s "$@" "$@-t" && exit 0; \
+-        $(JAVA) $(GWTC_JVM_ARGS) -cp $(GWT_CLASSPATH) com.google.gwt.dev.Compiler \
++        $(JAVA) -Djava.util.prefs.userRoot=$(HOME) $(GWTC_JVM_ARGS) -cp $(GWT_CLASSPATH) com.google.gwt.dev.Compiler \
+             $(GWTC_ARGS) -war gwt tsd.QueryUi
+        @mv "$@-t" "$@"
+ gwtdev: .gwtc-stamp
 @@ -1468,7 +1468,7 @@ gwttsd: staticroot
  # how to tell it to install a bunch of files recursively for which I don't
  # know ahead of time what the file names are.
  install-data-local: staticroot install-data-lib install-data-tools \
 -    install-data-bin install-data-etc
 +    install-data-bin
         @$(NORMAL_INSTALL)
         test -z "$(staticdir)" || $(mkdir_p) "$(DESTDIR)$(staticdir)"
         @set -e; pwd; ls -lFh; cd "$(DEV_TSD_STATICROOT)"; \