Shorter log format, use ./configure --enable-shortlog

Shorter log format uses just seconds precision.

refs #2398

Fixed off-by-one.

Change-Id: Ie8fa417ac75c97be9be917833464b13591a661f2

configure.ac

@@ -146,6 +146,11 @@ AC_ARG_ENABLE([lto],
       *)  AC_MSG_ERROR([bad value ${enableval} for --enable-lto]) ;;
     esac])
 
+# Check for shortlog
+AC_ARG_ENABLE([shortlog],
+    AS_HELP_STRING([--enable-shortlog], [enable shorter date format in log messages [default=no]]),
+    AC_DEFINE([ENABLE_SHORTLOG], [1], [short log format]))
+
 AX_CHECK_COMPILER_FLAGS("-fpredictive-commoning", [CFLAGS="$CFLAGS -fpredictive-commoning"], [])
 
 # Disable strict aliasing

src/common/log.c

@@ -220,15 +220,17 @@ static int _log_msg(logsrc_t src, int level, const char *msg)
 	time_t sec = tv.tv_sec;
 	if (localtime_r(&sec, &lt) != NULL) {
 		tlen = strftime(tstr, sizeof(tstr),
-				"%Y-%m-%dT%H:%M:%S", &lt);
+				"%Y-%m-%dT%H:%M:%S ", &lt);
+#ifndef ENABLE_SHORTLOG
 		if (tlen > 0) {
 			char pm = (lt.tm_gmtoff > 0) ? '+' : '-';
-			snprintf(tstr + tlen, sizeof(tstr) - tlen,
+			snprintf(tstr + tlen - 1, sizeof(tstr) - tlen + 1,
 			         ".%.6lu%c%.2u:%.2u ",
 			         (unsigned long)tv.tv_usec, pm,
 			         (unsigned int)lt.tm_gmtoff / 3600,
 			         (unsigned int)(lt.tm_gmtoff / 60) % 60);
 		}
+#endif /* ENABLE_SHORTLOG */
 	}
 
 	// Log streams