From: Vincent Bernat <vincent@bernat.im>
Date: Fri, 20 May 2016 09:10:55 +0000 (+0200)
Subject: client: add a way to limit the number of events received by "watch"
X-Git-Tag: 0.9.3~3
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a7c549493dca0ed64d6c5dbdc76060dff3d8427d;p=thirdparty%2Flldpd.git

client: add a way to limit the number of events received by "watch"
---

diff --git a/src/client/lldpcli.8.in b/src/client/lldpcli.8.in
index fb1ca7a4..b06e4b8c 100644
--- a/src/client/lldpcli.8.in
+++ b/src/client/lldpcli.8.in
@@ -142,6 +142,7 @@ view.
 .Op ports Ar ethX Op ,...
 .Op Cd details | summary
 .Op Cd hidden
+.Op Cd limit Ar X
 .Bd -ragged -offset XXXXXX
 Watch for any neighbor changes and report them as soon as they
 happen. When specifying ports, the changes are only reported when
@@ -149,7 +150,11 @@ happening on the given ports.
 .Cd hidden , summary
 and
 .Cd details
-have the same meaning than previously described.
+have the same meaning than previously described. If
+.Cd limit
+is specificed,
+.Nm
+will exit after receiving the specified number of events.
 .Ed
 
 .Cd show configuration
diff --git a/src/client/show.c b/src/client/show.c
index f61fbff3..57fc8b20 100644
--- a/src/client/show.c
+++ b/src/client/show.c
@@ -17,6 +17,7 @@
 
 #include "client.h"
 #include <string.h>
+#include <limits.h>
 
 /**
  * Show neighbors.
@@ -117,6 +118,7 @@ cmd_show_configuration(struct lldpctl_conn_t *conn, struct writer *w,
 struct watcharg {
 	struct cmd_env *env;
 	struct writer *w;
+	size_t nb;
 };
 
 /**
@@ -175,6 +177,7 @@ watchcb(lldpctl_conn_t *conn,
 	    cmdenv_get(env, "detailed")?DISPLAY_DETAILS:
 	    DISPLAY_NORMAL, protocol);
 	tag_end(w);
+	wa->nb++;
 }
 
 /**
@@ -187,8 +190,21 @@ cmd_watch_neighbors(struct lldpctl_conn_t *conn, struct writer *w,
 	int watch = 1;
 	struct watcharg wa = {
 		.env = env,
-		.w = w
+		.w = w,
+		.nb = 0
 	};
+	const char *limit_str = cmdenv_get(env, "limit");
+	size_t limit = 0;
+
+	if (limit_str) {
+		const char *errstr;
+		limit = strtonum(limit_str, 1, LLONG_MAX, &errstr);
+		if (errstr != NULL) {
+			log_warnx("lldpctl", "specified limit (%s) is %s and ignored",
+			    limit_str, errstr);
+		}
+	}
+
 	log_debug("lldpctl", "watch for neighbor changes");
 	if (lldpctl_watch_callback(conn, watchcb, &wa) < 0) {
 		log_warnx("lldpctl", "unable to watch for neighbors. %s",
@@ -201,6 +217,8 @@ cmd_watch_neighbors(struct lldpctl_conn_t *conn, struct writer *w,
 			    lldpctl_last_strerror(conn));
 			watch = 0;
 		}
+		if (limit > 0 && wa.nb >= limit)
+			watch = 0;
 	}
 	return 0;
 }
@@ -339,11 +357,19 @@ register_commands_watch(struct cmd_node *root)
 		"Monitor neighbor changes",
 		NULL, NULL, NULL);
 
-	/* Neighbors data */
 	commands_new(watch,
 	    NEWLINE,
 	    "Monitor neighbors change",
 	    NULL, cmd_watch_neighbors, NULL);
 
+	commands_new(
+		commands_new(watch,
+		    "limit",
+		    "Don't show more than X events",
+		    cmd_check_no_env, NULL, "limit"),
+		NULL,
+		"Stop after getting X events",
+		NULL, cmd_store_env_value_and_pop2, "limit");
+
 	register_common_commands(watch, 1);
 }