merge r3473, r3474, r3385, r3386, r3537: signal processing stability: *) use sys_errlist[] in signal handler instead of non Async-Signal-Safe strerror_r() *) do not update time in the timer signal handler, since localtime_r() is not Async-Signal-Safe function *) use previously cached GMT offset value to update time from a signal handler *) change ngx_time_update() interface since there are no notification methods those return time *) introduce ngx_time_sigsafe_update() to update the error log time only *) change ngx_time_update() interface

--- a/src/core/ngx_cycle.c
+++ b/src/core/ngx_cycle.c
@@ -63,7 +63,7 @@ ngx_init_cycle(ngx_cycle_t *old_cycle)
     tp = ngx_timeofday();
     tp->sec = 0;
 
-    ngx_time_update(0, 0);
+    ngx_time_update();
 
 
     log = old_cycle->log;