From: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Date: Fri, 16 Nov 2018 18:55:57 +0000 (-0500)
Subject: Docs: document why a negative socket may be passed
X-Git-Tag: v2.12.0-rc1~745
X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=45798a31cc31b86a669221676ab490c035c8dfdd

Docs: document why a negative socket may be passed

The fix in 4821263c4 checks for a negative socket. While the
commit message explains the reason for the check, it is not
obvious why this check is needed when looking at the code
itself.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
---

diff --git a/src/bin/lttng-sessiond/ust-app.c b/src/bin/lttng-sessiond/ust-app.c
index 5b37a8e74..23f29c13c 100644
--- a/src/bin/lttng-sessiond/ust-app.c
+++ b/src/bin/lttng-sessiond/ust-app.c
@@ -489,6 +489,11 @@ void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
 			ust_registry_channel_del_free(registry, ua_chan->key,
 				sock >= 0);
 		}
+		/*
+		 * A negative socket can be used by the caller when
+		 * cleaning-up a ua_chan in an error path. Skip the
+		 * accounting in this case.
+		 */
 		if (sock >= 0) {
 			save_per_pid_lost_discarded_counters(ua_chan);
 		}