From: Eugene Syromyatnikov <evgsyr@gmail.com>
Date: Wed, 28 Mar 2018 14:22:04 +0000 (+0200)
Subject: strace.c: support simultaneous usage of -r and -t options
X-Git-Tag: v4.22~9
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=698e9c30d4f31cc5ee850c03a693769affe461a1;p=strace

strace.c: support simultaneous usage of -r and -t options

* strace.c (init): Do not set tflag when rflag is set.
(printleader): Handle rflag and tflag separately.
* strace.1.in (.SH OPTIONS): Add a note about differences between
the monotonic clock time  and the wall clock time.
* tests/options-syntax.test: Remove the check for
"-tt has no effect with -r" warning.
* NEWS: Mention this.

Suggested-by: Josh Triplett <josh@freedesktop.org>
Co-Authored-by: Dmitry V. Levin <ldv@altlinux.org>
Closes: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=466195
---

diff --git a/NEWS b/NEWS
index 2816f64e..171c657b 100644
--- a/NEWS
+++ b/NEWS
@@ -9,6 +9,8 @@ Noteworthy changes in release ?.?? (????-??-??)
     in the output of paths associated with file descriptors.
   * Data dump for write syscalls (-e write) is performed regardless
     of successfulness of these syscall (addresses Debian bug #436284).
+  * -r and -t options are now affect output independently.  Previously,
+    -r option led to ignoring of the -t option (addresses Debian bug #466195).
 
 * Improvements
   * Implemented delay injection (-e inject=SET:delay_enter= and
diff --git a/strace.1.in b/strace.1.in
index caa88244..3f47cbea 100644
--- a/strace.1.in
+++ b/strace.1.in
@@ -287,6 +287,13 @@ If given twice, suppress messages about process exit status.
 Print a relative timestamp upon entry to each system call.  This
 records the time difference between the beginning of successive
 system calls.
+Note that since
+.B \-r
+option uses the monotonic clock time for measuring time difference and not the
+wall clock time, its measurements can differ from the difference in time
+reported by the
+.B \-t
+option.
 .TP
 .BI "\-s " strsize
 Specify the maximum string size to print (the default is 32).  Note
diff --git a/strace.c b/strace.c
index 314fe0be..af2e9904 100644
--- a/strace.c
+++ b/strace.c
@@ -646,20 +646,9 @@ printleader(struct tcb *tcp)
 
 	if (tflag) {
 		struct timespec ts;
-		clock_gettime(rflag ? CLOCK_MONOTONIC : CLOCK_REALTIME, &ts);
+		clock_gettime(CLOCK_REALTIME, &ts);
 
-		if (rflag) {
-			static struct timespec ots;
-			if (ots.tv_sec == 0)
-				ots = ts;
-
-			struct timespec dts;
-			ts_sub(&dts, &ts, &ots);
-			ots = ts;
-
-			tprintf("%6ld.%06ld ",
-				(long) dts.tv_sec, (long) dts.tv_nsec / 1000);
-		} else if (tflag > 2) {
+		if (tflag > 2) {
 			tprintf("%lld.%06ld ",
 				(long long) ts.tv_sec, (long) ts.tv_nsec / 1000);
 		} else {
@@ -678,6 +667,25 @@ printleader(struct tcb *tcp)
 				tprintf("%s ", str);
 		}
 	}
+
+	if (rflag) {
+		struct timespec ts;
+		clock_gettime(CLOCK_MONOTONIC, &ts);
+
+		static struct timespec ots;
+		if (ots.tv_sec == 0)
+			ots = ts;
+
+		struct timespec dts;
+		ts_sub(&dts, &ts, &ots);
+		ots = ts;
+
+		tprintf("%s%6ld.%06ld%s ",
+			tflag ? "(+" : "",
+			(long) dts.tv_sec, (long) dts.tv_nsec / 1000,
+			tflag ? ")" : "");
+	}
+
 	if (iflag)
 		print_pc(tcp);
 }
@@ -1756,12 +1764,6 @@ init(int argc, char *argv[])
 			error_msg("-%c has no effect with -c", 'y');
 	}
 
-	if (rflag) {
-		if (tflag > 1)
-			error_msg("-tt has no effect with -r");
-		tflag = 1;
-	}
-
 	acolumn_spaces = xmalloc(acolumn + 1);
 	memset(acolumn_spaces, ' ', acolumn);
 	acolumn_spaces[acolumn] = '\0';
diff --git a/tests/options-syntax.test b/tests/options-syntax.test
index f81dd992..7b4a620e 100755
--- a/tests/options-syntax.test
+++ b/tests/options-syntax.test
@@ -92,9 +92,6 @@ $STRACE_EXE: -t has no effect with -c
 $STRACE_EXE: -T has no effect with -c
 $STRACE_EXE: -y has no effect with -c
 $STRACE_EXE: $umsg" -u :nosuchuser: -cirtTy true
-
-	check_e "-tt has no effect with -r
-$STRACE_EXE: $umsg" -u :nosuchuser: -r -tt true
 fi
 
 args='-p 2147483647'