X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-sessiond%2Fagent.c;h=f6f2f772e08af693c26268e10b0dfda5bed08d09;hp=bc72ff93f61ed16c7fa43c8a236c2d8464d7401c;hb=0c82ac624169ec9ec062f395e55abfe992d0fd91;hpb=e261a6cc54e9a5567bf12c963f96fe22e9cf345c

diff --git a/src/bin/lttng-sessiond/agent.c b/src/bin/lttng-sessiond/agent.c
index bc72ff93f..f6f2f772e 100644
--- a/src/bin/lttng-sessiond/agent.c
+++ b/src/bin/lttng-sessiond/agent.c
@@ -15,7 +15,6 @@
  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#define _GNU_SOURCE
 #define _LGPL_SOURCE
 #include <assert.h>
 #include <urcu/uatomic.h>
@@ -127,6 +126,12 @@ static int ht_match_event(struct cds_lfht_node *node,
 		goto no_match;
 	}
 
+	/* Filter expression */
+	if (strncmp(event->filter_expression, key->filter_expression,
+			strlen(event->filter_expression)) != 0) {
+		goto no_match;
+	}
+
 	return 1;
 
 no_match:
@@ -149,6 +154,7 @@ static void add_unique_agent_event(struct lttng_ht *ht,
 	key.name = event->name;
 	key.loglevel_value = event->loglevel_value;
 	key.loglevel_type = event->loglevel_type;
+	key.filter_expression = event->filter_expression;
 
 	node_ptr = cds_lfht_add_unique(ht->ht,
 			ht->hash_fct(event->node.key, lttng_ht_seed),
@@ -361,7 +367,9 @@ error:
 static int enable_event(struct agent_app *app, struct agent_event *event)
 {
 	int ret;
+	char *bytes_to_send;
 	uint64_t data_size;
+	size_t filter_expression_length;
 	uint32_t reply_ret_code;
 	struct lttcomm_agent_enable msg;
 	struct lttcomm_agent_generic_reply reply;
@@ -373,7 +381,16 @@ static int enable_event(struct agent_app *app, struct agent_event *event)
 	DBG2("Agent enabling event %s for app pid: %d and socket %d", event->name,
 			app->pid, app->sock->fd);
 
-	data_size = sizeof(msg);
+	/*
+	 * Calculate the payload's size, which is the fixed-size struct followed
+	 * by the variable-length filter expression (+1 for the ending \0).
+	 */
+	if (!event->filter_expression) {
+		filter_expression_length = 0;
+	} else {
+		filter_expression_length = strlen(event->filter_expression) + 1;
+	}
+	data_size = sizeof(msg) + filter_expression_length;
 
 	ret = send_header(app->sock, data_size, AGENT_CMD_ENABLE, 0);
 	if (ret < 0) {
@@ -381,10 +398,25 @@ static int enable_event(struct agent_app *app, struct agent_event *event)
 	}
 
 	memset(&msg, 0, sizeof(msg));
-	msg.loglevel_value = event->loglevel_value;
-	msg.loglevel_type = event->loglevel_type;
+	msg.loglevel_value = htobe32(event->loglevel_value);
+	msg.loglevel_type = htobe32(event->loglevel_type);
 	strncpy(msg.name, event->name, sizeof(msg.name));
-	ret = send_payload(app->sock, &msg, sizeof(msg));
+	msg.filter_expression_length = htobe32(filter_expression_length);
+
+	bytes_to_send = zmalloc(data_size);
+	if (!bytes_to_send) {
+		ret = LTTNG_ERR_NOMEM;
+		goto error;
+	}
+
+	memcpy(bytes_to_send, &msg, sizeof(msg));
+	if (filter_expression_length > 0) {
+		memcpy(bytes_to_send + sizeof(msg), event->filter_expression,
+				filter_expression_length);
+	}
+
+	ret = send_payload(app->sock, bytes_to_send, data_size);
+	free(bytes_to_send);
 	if (ret < 0) {
 		goto error_io;
 	}
@@ -834,8 +866,10 @@ struct agent_event *agent_create_event(const char *name,
 {
 	struct agent_event *event = NULL;
 
-	DBG3("Agent create new event with name %s, loglevel type %d and loglevel value %d",
-		name, loglevel_type, loglevel_value);
+	DBG3("Agent create new event with name %s, loglevel type %d, \
+			loglevel value %d and filter %s",
+			name, loglevel_type, loglevel_value,
+			filter_expression ? filter_expression : "NULL");
 
 	if (!name) {
 		ERR("Failed to create agent event; no name provided.");
@@ -918,15 +952,16 @@ void agent_event_next_duplicate(const char *name,
 }
 
 /*
- * Find a agent event in the given agent using name and loglevel.
+ * Find a agent event in the given agent using name, loglevel and filter.
  *
- * RCU read side lock MUST be acquired.
+ * RCU read side lock MUST be acquired. It must be kept for as long as
+ * the returned agent_event is used.
  *
  * Return object if found else NULL.
  */
 struct agent_event *agent_find_event(const char *name,
 		enum lttng_loglevel_type loglevel_type, int loglevel_value,
-		struct agent *agt)
+		char *filter_expression, struct agent *agt)
 {
 	struct lttng_ht_node_str *node;
 	struct lttng_ht_iter iter;
@@ -941,6 +976,7 @@ struct agent_event *agent_find_event(const char *name,
 	key.name = name;
 	key.loglevel_value = loglevel_value;
 	key.loglevel_type = loglevel_type;
+	key.filter_expression = filter_expression;
 
 	cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
 			ht_match_event, &key, &iter.iter);