Bash unable to print epoch timestamp
Brian Inglis
Brian.Inglis@SystematicSw.ab.ca
Tue Oct 27 01:16:00 GMT 2015
> -------- Forwarded Message --------
> Subject: Fwd: Re: Bash unable to print epoch timestamp
> Date: Fri, 23 Oct 2015 14:32:44 -0600
> From: Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
> Reply-To: Brian.Inglis@SystematicSw.ab.ca
> Organisation: Systematic Software
> To: corinna-cygwin@cygwin.com
>
> Already forwarded as below to cygwin and ...patches-allow...
> - should be HTML free and pass filters?
On 2015-10-26 11:34, Brian Inglis wrote:
> Third time lucky - pasting inline into email and resending to all previous lists.
>
> Please note that conversion into too-small buffer size in regression test may not have expected result!
>
> Tried to build with below and variants:
> gcc -D_REGRESSION_TEST -D_COMPILING_NEWLIB -Dsniprintf=snprintf -I/usr/src/cygwin-2.2.1-1.src/newlib-cygwin/winsup/cygwin/include -o strftime-s-test strftime.c
> gives undef refs for __cygwin_gettzname, __cygwin_gettzoffset, __get_current_time_locale, __tz_lock, __tz_unlock,
> _tzset_unlocked
>
> Build stc with std cmdline and current strftime works and does demo issue.
Sorry - redo with the file existing!
--
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada
----- >8 ----- 8< -----
/* newlib/libc/time/strftime.c %s format STC */
#include <stdio.h>
#include <time.h>
int main( int argc, char **argv) {
char ss[BUFSIZ] = "";
time_t tt = time( NULL );
struct tm *tp = gmtime( &tt );
tt = mktime( tp );
size_t st = strftime( ss, sizeof ss, "%s", tp);
int rc = puts( ss );
st = strftime( ss, sizeof ss, "%T", tp);
rc = puts( ss );
return rc;
}
----- >8 ----- 8< -----
--- a/newlib/ChangeLog 2015-08-20 03:39:23.000000000 -0600
+++ b/newlib/ChangeLog 2015-10-26 18:50:44.165368900 -0600
@@ -1,3 +1,8 @@
+2015-10-12 Brian Inglis <Brian.Inglis@SystematicSw.ab.ca>
+
+ * libc/time/strftime.c (__strftime): add support for %s (seconds from
+ Unix epoch)
+
2015-08-07 Stefan Wallentowitz <stefan.wallentowitz@tum.de>
* libc/sys/or1k/mlock.c: Fix exception enable saving
--- a/newlib/libc/time/strftime.c 2015-08-20 03:39:24.000000000 -0600
+++ b/newlib/libc/time/strftime.c 2015-10-26 04:27:12.244016200 -0600
@@ -166,6 +166,10 @@ notations, the result is an empty string
o %R
The 24-hour time, to the minute. Equivalent to "%H:%M". [tm_min, tm_hour]
+o %s
+The time elapsed, in seconds, since the start of the Unix epoch at
+1970-01-01 00:00:00 UTC.
+
o %S
The second, formatted with two digits (from `<<00>>' to `<<60>>'). The
value 60 accounts for the occasional leap second. [tm_sec]
@@ -1109,6 +1113,74 @@ recurse:
tim_p->tm_hour, tim_p->tm_min);
CHECK_LENGTH ();
break;
+ case CQ('s'):
+/*
+ * From:
+ * The Open Group Base Specifications Issue 7
+ * IEEE Std 1003.1, 2013 Edition
+ * Copyright (c) 2001-2013 The IEEE and The Open Group
+ * XBD Base Definitions
+ * 4. General Concepts
+ * 4.15 Seconds Since the Epoch
+ * A value that approximates the number of seconds that have elapsed since the
+ * Epoch. A Coordinated Universal Time name (specified in terms of seconds
+ * (tm_sec), minutes (tm_min), hours (tm_hour), days since January 1 of the year
+ * (tm_yday), and calendar year minus 1900 (tm_year)) is related to a time
+ * represented as seconds since the Epoch, according to the expression below.
+ * If the year is <1970 or the value is negative, the relationship is undefined.
+ * If the year is >=1970 and the value is non-negative, the value is related to a
+ * Coordinated Universal Time name according to the C-language expression, where
+ * tm_sec, tm_min, tm_hour, tm_yday, and tm_year are all integer types:
+ * tm_sec + tm_min*60 + tm_hour*3600 + tm_yday*86400 +
+ * (tm_year-70)*31536000 + ((tm_year-69)/4)*86400 -
+ * ((tm_year-1)/100)*86400 + ((tm_year+299)/400)*86400
+ * OR
+ * ((((tm_year-69)/4 - (tm_year-1)/100 + (tm_year+299)/400 +
+ * (tm_year-70)*365 + tm_yday)*24 + tm_hour)*60 + tm_min)*60 + tm_sec
+ */
+/* modified from %z case by hoisting offset outside if block and initializing */
+ {
+ long offset; /* offset < 0 => W of GMT, > 0 => E of GMT:
+ offset = 0; subtract to get UTC */
+
+ if (tim_p->tm_isdst >= 0)
+ {
+ TZ_LOCK;
+ if (!tzset_called)
+ {
+ _tzset_unlocked ();
+ tzset_called = 1;
+ }
+
+#if defined (__CYGWIN__)
+ /* Cygwin must check if the application has been built with or
+ without the extra tm members for backward compatibility, and
+ then use either that or the old method fetching from tzinfo.
+ Rather than pulling in the version check infrastructure, we
+ just call a Cygwin function. */
+ extern long __cygwin_gettzoffset (const struct tm *tmp);
+ offset = __cygwin_gettzoffset (tim_p);
+#elif defined (__TM_GMTOFF)
+ offset = tim_p->__TM_GMTOFF;
+#else
+ __tzinfo_type *tz = __gettzinfo ();
+ /* The sign of this is exactly opposite the envvar TZ. We
+ could directly use the global _timezone for tm_isdst==0,
+ but have to use __tzrule for daylight savings. */
+ offset = -tz->__tzrule[tim_p->tm_isdst > 0].offset;
+#endif
+ TZ_UNLOCK;
+ }
+ len = snprintf (&s[count], maxsize - count, CQ("%lld"),
+ (((((long long)tim_p->tm_year - 69)/4
+ - (tim_p->tm_year - 1)/100
+ + (tim_p->tm_year + 299)/400
+ + (tim_p->tm_year - 70)*365 + tim_p->tm_yday)*24
+ + tim_p->tm_hour)*60 + tim_p->tm_min)*60
+ + tim_p->tm_sec - offset);
+ CHECK_LENGTH ();
+ }
+ break;
case CQ('S'):
#ifdef _WANT_C99_TIME_FORMATS
if (alt != CQ('O') || !*alt_digits
@@ -1442,6 +1514,7 @@ const struct test Vec0[] = {
{ CQ("%p"), 2+1, EXP(CQ("AM")) },
{ CQ("%r"), 11+1, EXP(CQ("09:53:47 AM")) },
{ CQ("%R"), 5+1, EXP(CQ("09:53")) },
+ { CQ("%s"), 2+1, EXP(CQ("1230648827")) },
{ CQ("%S"), 2+1, EXP(CQ("47")) },
{ CQ("%t"), 1+1, EXP(CQ("\t")) },
{ CQ("%T"), 8+1, EXP(CQ("09:53:47")) },
@@ -1502,6 +1575,7 @@ const struct test Vec1[] = {
{ CQ("%p"), 2+1, EXP(CQ("PM")) },
{ CQ("%r"), 11+1, EXP(CQ("11:01:13 PM")) },
{ CQ("%R"), 5+1, EXP(CQ("23:01")) },
+ { CQ("%s"), 2+1, EXP(CQ("1215054073")) },
{ CQ("%S"), 2+1, EXP(CQ("13")) },
{ CQ("%t"), 1+1, EXP(CQ("\t")) },
{ CQ("%T"), 8+1, EXP(CQ("23:01:13")) },
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