From: Philippe Proulx <eeppeliteloop@gmail.com>
Date: Fri, 28 Jul 2017 19:48:32 +0000 (-0400)
Subject: lttng enable-channel: --blocking-timeout opt.: use `inf` instead of -1
X-Git-Tag: v2.10.0~3
X-Git-Url: https://git.lttng.org./?a=commitdiff_plain;h=9e23d3ff2b04c7e2eaa4a08b7439b18f0bd355bb;p=lttng-tools.git

lttng enable-channel: --blocking-timeout opt.: use `inf` instead of -1

It might be -1 for the API, but for a command-line interface used by
humans, `inf` is more meaningful than -1.

Signed-off-by: Philippe Proulx <eeppeliteloop@gmail.com>
Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng/commands/enable_channels.c b/src/bin/lttng/commands/enable_channels.c
index 19490477e..48c211095 100644
--- a/src/bin/lttng/commands/enable_channels.c
+++ b/src/bin/lttng/commands/enable_channels.c
@@ -556,42 +556,50 @@ int cmd_enable_channels(int argc, const char **argv)
 
 			errno = 0;
 			opt_arg = poptGetOptArg(pc);
+
+			if (strcmp(opt_arg, "inf") == 0) {
+				opt_blocking_timeout.value = (int64_t) -1;
+				opt_blocking_timeout.set = true;
+				DBG("Channel blocking timeout set to infinity");
+				break;
+			}
+
 			v = strtoll(opt_arg, NULL, 0);
 			if (errno != 0 || (!isdigit(opt_arg[0]) && opt_arg[0] != '-')
-					|| v < -1) {
+					|| v < 0) {
 				ERR("Wrong value in --blocking-timeout parameter: %s", opt_arg);
 				ret = CMD_ERROR;
 				goto end;
 			}
-			if (v >= 0) {
-				/*
-				 * While LTTng-UST and LTTng-tools will accept
-				 * a blocking timeout expressed in µs, the
-				 * current tracer implementation relies on
-				 * poll() which takes an "int timeout" parameter
-				 * expressed in msec.
-				 *
-				 * Since the error reporting from the tracer
-				 * is not precise, we perform this check here
-				 * to provide a helpful error message in case of
-				 * overflow.
-				 *
-				 * The setter (liblttng-ctl) also performs an
-				 * equivalent check.
-				 */
-				v_msec = v / 1000;
-				if (v_msec != (int32_t) v_msec) {
-					ERR("32-bit milliseconds overflow in --blocking-timeout parameter: %s", opt_arg);
-					ret = CMD_ERROR;
-					goto end;
-				}
-			} else if (v != -1) {
-				ERR("Invalid negative value passed as --blocking-timeout parameter; -1 (block forever) is the only valid negative value");
+
+			/*
+			 * While LTTng-UST and LTTng-tools will accept a
+			 * blocking timeout expressed in µs, the current
+			 * tracer implementation relies on poll() which
+			 * takes an "int timeout" parameter expressed in
+			 * msec.
+			 *
+			 * Since the error reporting from the tracer is
+			 * not precise, we perform this check here to
+			 * provide a helpful error message in case of
+			 * overflow.
+			 *
+			 * The setter (liblttng-ctl) also performs an
+			 * equivalent check.
+			 */
+			v_msec = v / 1000;
+			if (v_msec != (int32_t) v_msec) {
+				ERR("32-bit milliseconds overflow in --blocking-timeout parameter: %s", opt_arg);
+				ret = CMD_ERROR;
+				goto end;
 			}
+
 			opt_blocking_timeout.value = (int64_t) v;
 			opt_blocking_timeout.set = true;
-			DBG("Channel blocking timeout set to %" PRId64 " (µs)",
-					opt_blocking_timeout.value);
+			DBG("Channel blocking timeout set to %" PRId64 " µs%s",
+					opt_blocking_timeout.value,
+					opt_blocking_timeout.value == 0 ?
+						" (non-blocking)" : "");
 			break;
 		}
 		case OPT_USERSPACE:
diff --git a/tests/regression/ust/blocking/test_blocking b/tests/regression/ust/blocking/test_blocking
index c5c95903b..b1c3f2d09 100755
--- a/tests/regression/ust/blocking/test_blocking
+++ b/tests/regression/ust/blocking/test_blocking
@@ -60,12 +60,12 @@ function test_ust_implicit_no_blocking()
 function test_ust_implicit_no_blocking_with_channel_blocking()
 {
 	NUM_EVENT=5000000
-	diag "UST implicit non-blocking mode (default) with blocking-timeout=-1 channel: will hang if fails"
+	diag "UST implicit non-blocking mode (default) with blocking-timeout=inf channel: will hang if fails"
 
 	start_lttng_sessiond
 	# session in no-output mode
 	create_lttng_session_no_output $SESSION_NAME
-	enable_ust_lttng_channel_ok $SESSION_NAME $CHANNEL_NAME "--blocking-timeout=-1"
+	enable_ust_lttng_channel_ok $SESSION_NAME $CHANNEL_NAME "--blocking-timeout=inf"
 	enable_ust_lttng_event_ok $SESSION_NAME "$EVENT_NAME" $CHANNEL_NAME
 	start_lttng_tracing_ok $SESSION_NAME
 	run_app
@@ -125,7 +125,7 @@ function test_ust_blocking_no_discard()
 	start_lttng_sessiond
 	create_lttng_session_ok $SESSION_NAME $TRACE_PATH
 	# infinite blocking timeout
-	enable_ust_lttng_channel_ok $SESSION_NAME $CHANNEL_NAME "--blocking-timeout=-1"
+	enable_ust_lttng_channel_ok $SESSION_NAME $CHANNEL_NAME "--blocking-timeout=inf"
 	enable_ust_lttng_event_ok $SESSION_NAME "$EVENT_NAME" $CHANNEL_NAME
 	start_lttng_tracing_ok $SESSION_NAME
 	LTTNG_UST_ALLOW_BLOCKING=1 run_app