From: Eugene Syromyatnikov <evgsyr@gmail.com>
Date: Fri, 2 Sep 2016 15:27:18 +0000 (+0300)
Subject: tests/futex: add support to sprintrc for return codes other than 0 and -1
X-Git-Tag: v4.14~131
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8bb9f473e44dc75f3462b9d9753ae3bfa309b1a9;p=strace

tests/futex: add support to sprintrc for return codes other than 0 and -1

* tests/futex.c (sprintrc): Print the actual return code provided,
not just "0".  Check snprintf return code.
---

diff --git a/tests/futex.c b/tests/futex.c
index 28d9df87..09a6c25c 100644
--- a/tests/futex.c
+++ b/tests/futex.c
@@ -150,7 +150,15 @@ const char *sprintrc(long rc)
 	if (rc == 0)
 		return "0";
 
-	snprintf(buf, sizeof(buf), "-1 %s (%m)", errno2name());
+	int ret = (rc == -1)
+		? snprintf(buf, sizeof(buf), "-1 %s (%m)", errno2name())
+		: snprintf(buf, sizeof(buf), "%ld", rc);
+
+	if (ret < 0)
+		perror_msg_and_fail("snprintf");
+	if ((size_t) ret >= sizeof(buf))
+		error_msg_and_fail("snprintf overflow: got %d, expected "
+			"no more than %zu", ret, sizeof(buf));
 
 	return buf;
 }