X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=src%2Fcommon%2Ftrigger.c;h=0afea92fcc8f56280b1109cce2b6e13555878fdb;hb=a0377dfefe40662ba7d68617bce6ff467114136c;hp=ad0d5df1ba9c26644f8ee08bb61245c0d244392b;hpb=c738df170902f40de6d8e53c9f214a5308e4182b;p=lttng-tools.git

diff --git a/src/common/trigger.c b/src/common/trigger.c
index ad0d5df1b..0afea92fc 100644
--- a/src/common/trigger.c
+++ b/src/common/trigger.c
@@ -5,24 +5,25 @@
  *
  */
 
-#include <lttng/trigger/trigger-internal.h>
-#include <lttng/condition/condition-internal.h>
-#include <lttng/condition/on-event-internal.h>
-#include <lttng/condition/on-event.h>
-#include <lttng/condition/on-event-internal.h>
-#include <lttng/condition/buffer-usage.h>
-#include <lttng/event-rule/event-rule-internal.h>
-#include <lttng/event-expr-internal.h>
-#include <lttng/action/action-internal.h>
 #include <common/credentials.h>
-#include <common/payload.h>
-#include <common/payload-view.h>
-#include <lttng/domain.h>
-#include <common/error.h>
 #include <common/dynamic-array.h>
+#include <common/error.h>
+#include <common/mi-lttng.h>
 #include <common/optional.h>
-#include <assert.h>
+#include <common/payload-view.h>
+#include <common/payload.h>
 #include <inttypes.h>
+#include <lttng/action/action-internal.h>
+#include <lttng/condition/buffer-usage.h>
+#include <lttng/condition/condition-internal.h>
+#include <lttng/condition/event-rule-matches-internal.h>
+#include <lttng/condition/event-rule-matches.h>
+#include <lttng/domain.h>
+#include <lttng/error-query-internal.h>
+#include <lttng/event-expr-internal.h>
+#include <lttng/event-rule/event-rule-internal.h>
+#include <lttng/trigger/trigger-internal.h>
+#include <pthread.h>
 
 LTTNG_HIDDEN
 bool lttng_trigger_validate(const struct lttng_trigger *trigger)
@@ -62,15 +63,15 @@ struct lttng_trigger *lttng_trigger_create(
 
 	urcu_ref_init(&trigger->ref);
 
-	trigger->firing_policy.type = LTTNG_TRIGGER_FIRING_POLICY_EVERY_N;
-	trigger->firing_policy.threshold = 1;
-
 	lttng_condition_get(condition);
 	trigger->condition = condition;
 
 	lttng_action_get(action);
 	trigger->action = action;
 
+	pthread_mutex_init(&trigger->lock, NULL);
+	trigger->registered = false;
+
 end:
 	return trigger;
 }
@@ -117,13 +118,15 @@ static void trigger_destroy_ref(struct urcu_ref *ref)
 	struct lttng_condition *condition =
 			lttng_trigger_get_condition(trigger);
 
-	assert(action);
-	assert(condition);
+	LTTNG_ASSERT(action);
+	LTTNG_ASSERT(condition);
 
 	/* Release ownership. */
 	lttng_action_put(action);
 	lttng_condition_put(condition);
 
+	pthread_mutex_destroy(&trigger->lock);
+
 	free(trigger->name);
 	free(trigger);
 }
@@ -133,23 +136,6 @@ void lttng_trigger_destroy(struct lttng_trigger *trigger)
 	lttng_trigger_put(trigger);
 }
 
-static bool is_firing_policy_valid(enum lttng_trigger_firing_policy policy)
-{
-	bool valid = false;
-
-	switch (policy) {
-	case LTTNG_TRIGGER_FIRING_POLICY_EVERY_N:
-	case LTTNG_TRIGGER_FIRING_POLICY_ONCE_AFTER_N:
-		valid = true;
-		break;
-	default:
-		valid = false;
-		break;
-	}
-
-	return valid;
-}
-
 LTTNG_HIDDEN
 ssize_t lttng_trigger_create_from_payload(
 		struct lttng_payload_view *src_view,
@@ -160,8 +146,6 @@ ssize_t lttng_trigger_create_from_payload(
 	struct lttng_action *action = NULL;
 	const struct lttng_trigger_comm *trigger_comm;
 	const char *name = NULL;
-	uint64_t firing_policy_threshold;
-	enum lttng_trigger_firing_policy firing_policy;
 	struct lttng_credentials creds = {
 		.uid = LTTNG_OPTIONAL_INIT_UNSET,
 		.gid = LTTNG_OPTIONAL_INIT_UNSET,
@@ -196,13 +180,6 @@ ssize_t lttng_trigger_create_from_payload(
 
 	offset += sizeof(*trigger_comm);
 
-	firing_policy = trigger_comm->firing_policy_type;
-	if (!is_firing_policy_valid(firing_policy)) {
-		ret =-1;
-		goto end;
-	}
-
-	firing_policy_threshold = trigger_comm->firing_policy_threshold;
 	if (trigger_comm->name_length != 0) {
 		/* Name. */
 		const struct lttng_payload_view name_view =
@@ -291,19 +268,6 @@ ssize_t lttng_trigger_create_from_payload(
 		}
 	}
 
-	/* Set the policy. */
-	{
-		const enum lttng_trigger_status status =
-				lttng_trigger_set_firing_policy(trigger,
-						firing_policy,
-						firing_policy_threshold);
-
-		if (status != LTTNG_TRIGGER_STATUS_OK) {
-			ret = -1;
-			goto end;
-		}
-	}
-
 	ret = offset;
 
 error:
@@ -334,7 +298,7 @@ int lttng_trigger_serialize(const struct lttng_trigger *trigger,
 	const struct lttng_credentials *creds = NULL;
 
 	creds = lttng_trigger_get_credentials(trigger);
-	assert(creds);
+	LTTNG_ASSERT(creds);
 
 	trigger_comm.uid = LTTNG_OPTIONAL_GET(creds->uid);
 
@@ -345,8 +309,6 @@ int lttng_trigger_serialize(const struct lttng_trigger *trigger,
 	}
 
 	trigger_comm.name_length = size_name;
-	trigger_comm.firing_policy_type = (uint8_t) trigger->firing_policy.type;
-	trigger_comm.firing_policy_threshold = (uint64_t) trigger->firing_policy.threshold;
 
 	header_offset = payload->buffer.size;
 	ret = lttng_dynamic_buffer_append(&payload->buffer, &trigger_comm,
@@ -385,17 +347,15 @@ LTTNG_HIDDEN
 bool lttng_trigger_is_equal(
 		const struct lttng_trigger *a, const struct lttng_trigger *b)
 {
-	if (a->firing_policy.type != b->firing_policy.type) {
+	if (!!a->name != !!b->name) {
+		/* Both must be either anonymous or named. */
 		return false;
 	}
 
-	if (a->firing_policy.threshold != b->firing_policy.threshold) {
+	if (a->name && strcmp(a->name, b->name) != 0) {
 		return false;
 	}
 
-	/*
-	 * Name is not taken into account since it is cosmetic only.
-	 */
 	if (!lttng_condition_is_equal(a->condition, b->condition)) {
 		return false;
 	}
@@ -409,25 +369,44 @@ bool lttng_trigger_is_equal(
 		return false;
 	}
 
+	if (a->is_hidden != b->is_hidden) {
+		return false;
+	}
+
 	return true;
 }
 
+LTTNG_HIDDEN
+bool lttng_trigger_is_hidden(const struct lttng_trigger *trigger)
+{
+	return trigger->is_hidden;
+}
+
+LTTNG_HIDDEN
+void lttng_trigger_set_hidden(struct lttng_trigger *trigger)
+{
+	LTTNG_ASSERT(!trigger->is_hidden);
+	trigger->is_hidden = true;
+}
+
+LTTNG_HIDDEN
 enum lttng_trigger_status lttng_trigger_set_name(struct lttng_trigger *trigger,
 		const char* name)
 {
 	char *name_copy = NULL;
 	enum lttng_trigger_status status = LTTNG_TRIGGER_STATUS_OK;
 
-	if (!trigger || !name ||
-			strlen(name) == 0) {
+	if (!trigger) {
 		status = LTTNG_TRIGGER_STATUS_INVALID;
 		goto end;
 	}
 
-	name_copy = strdup(name);
-	if (!name_copy) {
-		status = LTTNG_TRIGGER_STATUS_ERROR;
-		goto end;
+	if (name) {
+		name_copy = strdup(name);
+		if (!name_copy) {
+			status = LTTNG_TRIGGER_STATUS_ERROR;
+			goto end;
+		}
 	}
 
 	free(trigger->name);
@@ -478,14 +457,14 @@ LTTNG_HIDDEN
 void lttng_trigger_set_tracer_token(struct lttng_trigger *trigger,
 		uint64_t token)
 {
-	assert(trigger);
+	LTTNG_ASSERT(trigger);
 	LTTNG_OPTIONAL_SET(&trigger->tracer_token, token);
 }
 
 LTTNG_HIDDEN
 uint64_t lttng_trigger_get_tracer_token(const struct lttng_trigger *trigger)
 {
-	assert(trigger);
+	LTTNG_ASSERT(trigger);
 
 	return LTTNG_OPTIONAL_GET(trigger->tracer_token);
 }
@@ -497,7 +476,7 @@ int lttng_trigger_generate_name(struct lttng_trigger *trigger,
 	int ret = 0;
 	char *generated_name = NULL;
 
-	ret = asprintf(&generated_name, "T%" PRIu64 "", unique_id);
+	ret = asprintf(&generated_name, "trigger%" PRIu64 "", unique_id);
 	if (ret < 0) {
 		ERR("Failed to generate trigger name");
 		ret = -1;
@@ -556,7 +535,7 @@ struct lttng_trigger *lttng_triggers_borrow_mutable_at_index(
 {
 	struct lttng_trigger *trigger = NULL;
 
-	assert(triggers);
+	LTTNG_ASSERT(triggers);
 	if (index >= lttng_dynamic_pointer_array_get_count(&triggers->array)) {
 		goto end;
 	}
@@ -574,8 +553,8 @@ int lttng_triggers_add(
 {
 	int ret;
 
-	assert(triggers);
-	assert(trigger);
+	LTTNG_ASSERT(triggers);
+	LTTNG_ASSERT(trigger);
 
 	lttng_trigger_get(trigger);
 
@@ -587,6 +566,40 @@ int lttng_triggers_add(
 	return ret;
 }
 
+LTTNG_HIDDEN
+int lttng_triggers_remove_hidden_triggers(struct lttng_triggers *triggers)
+{
+	int ret;
+	unsigned int trigger_count, i = 0;
+	enum lttng_trigger_status trigger_status;
+
+	LTTNG_ASSERT(triggers);
+
+	trigger_status = lttng_triggers_get_count(triggers, &trigger_count);
+	LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
+
+	while (i < trigger_count) {
+		const struct lttng_trigger *trigger =
+				lttng_triggers_get_at_index(triggers, i);
+
+		if (lttng_trigger_is_hidden(trigger)) {
+			ret = lttng_dynamic_pointer_array_remove_pointer(
+					&triggers->array, i);
+			if (ret) {
+				goto end;
+			}
+
+			trigger_count--;
+		} else {
+			i++;
+		}
+	}
+
+	ret = 0;
+end:
+	return ret;
+}
+
 const struct lttng_trigger *lttng_triggers_get_at_index(
 		const struct lttng_triggers *triggers, unsigned int index)
 {
@@ -649,7 +662,7 @@ int lttng_triggers_serialize(const struct lttng_triggers *triggers,
 		const struct lttng_trigger *trigger =
 				lttng_triggers_get_at_index(triggers, i);
 
-		assert(trigger);
+		LTTNG_ASSERT(trigger);
 
 		ret = lttng_trigger_serialize(trigger, payload);
 		if (ret) {
@@ -742,7 +755,7 @@ LTTNG_HIDDEN
 void lttng_trigger_set_credentials(struct lttng_trigger *trigger,
 		const struct lttng_credentials *creds)
 {
-	assert(creds);
+	LTTNG_ASSERT(creds);
 	trigger->creds = *creds;
 }
 
@@ -750,6 +763,7 @@ enum lttng_trigger_status lttng_trigger_set_owner_uid(
 		struct lttng_trigger *trigger, uid_t uid)
 {
 	enum lttng_trigger_status ret = LTTNG_TRIGGER_STATUS_OK;
+	const uid_t euid = geteuid();
 	const struct lttng_credentials creds = {
 		.uid = LTTNG_OPTIONAL_INIT_VALUE(uid),
 		.gid = LTTNG_OPTIONAL_INIT_UNSET,
@@ -761,7 +775,7 @@ enum lttng_trigger_status lttng_trigger_set_owner_uid(
 	}
 
 	/* Client-side validation only to report a clearer error. */
-	if (geteuid() != 0) {
+	if (euid != 0 && euid != uid) {
 		ret = LTTNG_TRIGGER_STATUS_PERMISSION_DENIED;
 		goto end;
 	}
@@ -795,97 +809,6 @@ end:
 	return ret;
 }
 
-enum lttng_trigger_status lttng_trigger_set_firing_policy(
-		struct lttng_trigger *trigger,
-		enum lttng_trigger_firing_policy policy_type,
-		uint64_t threshold)
-{
-	enum lttng_trigger_status ret = LTTNG_TRIGGER_STATUS_OK;
-	assert(trigger);
-
-	if (threshold < 1) {
-		ret = LTTNG_TRIGGER_STATUS_INVALID;
-		goto end;
-	}
-
-	trigger->firing_policy.type = policy_type;
-	trigger->firing_policy.threshold = threshold;
-
-end:
-	return ret;
-}
-
-enum lttng_trigger_status lttng_trigger_get_firing_policy(
-		const struct lttng_trigger *trigger,
-		enum lttng_trigger_firing_policy *policy_type,
-		uint64_t *threshold)
-{
-	enum lttng_trigger_status status = LTTNG_TRIGGER_STATUS_OK;
-
-	if (!trigger || !policy_type || !threshold) {
-		status = LTTNG_TRIGGER_STATUS_INVALID;
-		goto end;
-	}
-
-	*policy_type = trigger->firing_policy.type;
-	*threshold = trigger->firing_policy.threshold;
-
-end:
-	return status;
-}
-
-LTTNG_HIDDEN
-bool lttng_trigger_should_fire(const struct lttng_trigger *trigger)
-{
-	bool ready_to_fire = false;
-
-	assert(trigger);
-
-	switch (trigger->firing_policy.type) {
-	case LTTNG_TRIGGER_FIRING_POLICY_EVERY_N:
-		if (trigger->firing_policy.current_count < trigger->firing_policy.threshold) {
-			ready_to_fire = true;
-		}
-		break;
-	case LTTNG_TRIGGER_FIRING_POLICY_ONCE_AFTER_N:
-		if (trigger->firing_policy.current_count < trigger->firing_policy.threshold) {
-			ready_to_fire = true;
-		}
-		break;
-	default:
-		abort();
-	};
-
-	return ready_to_fire;
-}
-
-LTTNG_HIDDEN
-void lttng_trigger_fire(struct lttng_trigger *trigger)
-{
-	assert(trigger);
-
-	trigger->firing_policy.current_count++;
-
-	switch (trigger->firing_policy.type) {
-	case LTTNG_TRIGGER_FIRING_POLICY_EVERY_N:
-		if (trigger->firing_policy.current_count == trigger->firing_policy.threshold) {
-			trigger->firing_policy.current_count = 0;
-		}
-
-		break;
-	case LTTNG_TRIGGER_FIRING_POLICY_ONCE_AFTER_N:
-		/*
-		 * TODO:
-		 * As an optimisation, deactivate the trigger condition and
-		 * remove any checks in the traced application or kernel since
-		 * the trigger will never fire again.
-		 */
-		break;
-	default:
-		abort();
-	};
-}
-
 LTTNG_HIDDEN
 enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 		const struct lttng_trigger *trigger)
@@ -895,8 +818,8 @@ enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 	enum lttng_condition_status c_status;
 	enum lttng_condition_type c_type;
 
-	assert(trigger);
-	assert(trigger->condition);
+	LTTNG_ASSERT(trigger);
+	LTTNG_ASSERT(trigger->condition);
 
 	c_type = lttng_condition_get_type(trigger->condition);
 	assert (c_type != LTTNG_CONDITION_TYPE_UNKNOWN);
@@ -908,11 +831,11 @@ enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 		/* Apply to any domain. */
 		type = LTTNG_DOMAIN_NONE;
 		break;
-	case LTTNG_CONDITION_TYPE_ON_EVENT:
+	case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES:
 		/* Return the domain of the event rule. */
-		c_status = lttng_condition_on_event_get_rule(
+		c_status = lttng_condition_event_rule_matches_get_rule(
 				trigger->condition, &event_rule);
-		assert(c_status == LTTNG_CONDITION_STATUS_OK);
+		LTTNG_ASSERT(c_status == LTTNG_CONDITION_STATUS_OK);
 		type = lttng_event_rule_get_domain_type(event_rule);
 		break;
 	case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH:
@@ -920,7 +843,7 @@ enum lttng_domain_type lttng_trigger_get_underlying_domain_type_restriction(
 		/* Return the domain of the channel being monitored. */
 		c_status = lttng_condition_buffer_usage_get_domain_type(
 				trigger->condition, &type);
-		assert(c_status == LTTNG_CONDITION_STATUS_OK);
+		LTTNG_ASSERT(c_status == LTTNG_CONDITION_STATUS_OK);
 		break;
 	default:
 		abort();
@@ -948,14 +871,14 @@ enum lttng_error_code lttng_trigger_generate_bytecode(
 	}
 
 	switch (lttng_condition_get_type(condition)) {
-	case LTTNG_CONDITION_TYPE_ON_EVENT:
+	case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES:
 	{
 		struct lttng_event_rule *event_rule;
 		const enum lttng_condition_status condition_status =
-				lttng_condition_on_event_borrow_rule_mutable(
-					condition, &event_rule);
+				lttng_condition_event_rule_matches_borrow_rule_mutable(
+						condition, &event_rule);
 
-		assert(condition_status == LTTNG_CONDITION_STATUS_OK);
+		LTTNG_ASSERT(condition_status == LTTNG_CONDITION_STATUS_OK);
 
 		/* Generate the filter bytecode. */
 		ret = lttng_event_rule_generate_filter_bytecode(
@@ -965,7 +888,7 @@ enum lttng_error_code lttng_trigger_generate_bytecode(
 		}
 
 		/* Generate the capture bytecode. */
-		ret = lttng_condition_on_event_generate_capture_descriptor_bytecode(
+		ret = lttng_condition_event_rule_matches_generate_capture_descriptor_bytecode(
 				condition);
 		if (ret != LTTNG_OK) {
 			goto end;
@@ -987,11 +910,16 @@ struct lttng_trigger *lttng_trigger_copy(const struct lttng_trigger *trigger)
 {
 	int ret;
 	struct lttng_payload copy_buffer;
+	struct lttng_condition *condition_copy = NULL;
+	struct lttng_action *action_copy = NULL;
 	struct lttng_trigger *copy = NULL;
+	enum lttng_trigger_status trigger_status;
+	const char *trigger_name;
+	uid_t trigger_owner_uid;
 
 	lttng_payload_init(&copy_buffer);
 
-	ret = lttng_trigger_serialize(trigger, &copy_buffer);
+	ret = lttng_condition_serialize(trigger->condition, &copy_buffer);
 	if (ret < 0) {
 		goto end;
 	}
@@ -1000,15 +928,79 @@ struct lttng_trigger *lttng_trigger_copy(const struct lttng_trigger *trigger)
 		struct lttng_payload_view view =
 				lttng_payload_view_from_payload(
 						&copy_buffer, 0, -1);
-		ret = lttng_trigger_create_from_payload(
-				&view, &copy);
+
+		ret = lttng_condition_create_from_payload(
+				&view, &condition_copy);
 		if (ret < 0) {
-			copy = NULL;
 			goto end;
 		}
 	}
 
+	lttng_payload_clear(&copy_buffer);
+
+	ret = lttng_action_serialize(trigger->action, &copy_buffer);
+	if (ret < 0) {
+		goto end;
+	}
+
+	{
+		struct lttng_payload_view view =
+				lttng_payload_view_from_payload(
+						&copy_buffer, 0, -1);
+
+		ret = lttng_action_create_from_payload(
+				&view, &action_copy);
+		if (ret < 0) {
+			goto end;
+		}
+	}
+
+	copy = lttng_trigger_create(condition_copy, action_copy);
+	if (!copy) {
+		ERR("Failed to allocate trigger during trigger copy");
+		goto end;
+	}
+
+	trigger_status = lttng_trigger_get_name(trigger, &trigger_name);
+	switch (trigger_status) {
+	case LTTNG_TRIGGER_STATUS_OK:
+		trigger_status = lttng_trigger_set_name(copy, trigger_name);
+		if (trigger_status != LTTNG_TRIGGER_STATUS_OK) {
+			ERR("Failed to set name of new trigger during copy");
+			goto error_cleanup_trigger;
+		}
+		break;
+	case LTTNG_TRIGGER_STATUS_UNSET:
+		break;
+	default:
+		ERR("Failed to get name of original trigger during copy");
+		goto error_cleanup_trigger;
+	}
+
+	trigger_status = lttng_trigger_get_owner_uid(
+			trigger, &trigger_owner_uid);
+	switch (trigger_status) {
+	case LTTNG_TRIGGER_STATUS_OK:
+		LTTNG_OPTIONAL_SET(&copy->creds.uid, trigger_owner_uid);
+		break;
+	case LTTNG_TRIGGER_STATUS_UNSET:
+		break;
+	default:
+		ERR("Failed to get owner uid of original trigger during copy");
+		goto error_cleanup_trigger;
+	}
+
+	copy->tracer_token = trigger->tracer_token;
+	copy->registered = trigger->registered;
+	copy->is_hidden = trigger->is_hidden;
+	goto end;
+
+error_cleanup_trigger:
+	lttng_trigger_destroy(copy);
+	copy = NULL;
 end:
+	lttng_condition_put(condition_copy);
+	lttng_action_put(action_copy);
 	lttng_payload_reset(&copy_buffer);
 	return copy;
 }
@@ -1021,7 +1013,7 @@ bool lttng_trigger_needs_tracer_notifier(const struct lttng_trigger *trigger)
 			lttng_trigger_get_const_condition(trigger);
 
 	switch (lttng_condition_get_type(condition)) {
-	case LTTNG_CONDITION_TYPE_ON_EVENT:
+	case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES:
 		needs_tracer_notifier = true;
 		goto end;
 	case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE:
@@ -1037,3 +1029,243 @@ bool lttng_trigger_needs_tracer_notifier(const struct lttng_trigger *trigger)
 end:
 	return needs_tracer_notifier;
 }
+
+LTTNG_HIDDEN
+void lttng_trigger_set_as_registered(struct lttng_trigger *trigger)
+{
+	pthread_mutex_lock(&trigger->lock);
+	trigger->registered = true;
+	pthread_mutex_unlock(&trigger->lock);
+}
+
+LTTNG_HIDDEN
+void lttng_trigger_set_as_unregistered(struct lttng_trigger *trigger)
+{
+	pthread_mutex_lock(&trigger->lock);
+	trigger->registered = false;
+	pthread_mutex_unlock(&trigger->lock);
+}
+
+/*
+ * The trigger must be locked before calling lttng_trigger_registered.
+ * The lock is necessary since a trigger can be unregistered at anytime.
+ * Manipulations requiring that the trigger be registered must always acquire
+ * the trigger lock for the duration of the manipulation using
+ * `lttng_trigger_lock` and `lttng_trigger_unlock`.
+ */
+LTTNG_HIDDEN
+bool lttng_trigger_is_registered(struct lttng_trigger *trigger)
+{
+	ASSERT_LOCKED(trigger->lock);
+	return trigger->registered;
+}
+
+LTTNG_HIDDEN
+void lttng_trigger_lock(struct lttng_trigger *trigger)
+{
+	pthread_mutex_lock(&trigger->lock);
+}
+
+LTTNG_HIDDEN
+void lttng_trigger_unlock(struct lttng_trigger *trigger)
+{
+	pthread_mutex_unlock(&trigger->lock);
+}
+
+LTTNG_HIDDEN
+enum lttng_error_code lttng_trigger_mi_serialize(const struct lttng_trigger *trigger,
+		struct mi_writer *writer,
+		const struct mi_lttng_error_query_callbacks
+				*error_query_callbacks)
+{
+	int ret;
+	enum lttng_error_code ret_code;
+	enum lttng_trigger_status trigger_status;
+	const struct lttng_condition *condition = NULL;
+	const struct lttng_action *action = NULL;
+	struct lttng_dynamic_array action_path_indexes;
+	uid_t owner_uid;
+
+	LTTNG_ASSERT(trigger);
+	LTTNG_ASSERT(writer);
+
+	lttng_dynamic_array_init(&action_path_indexes, sizeof(uint64_t), NULL);
+
+	/* Open trigger element. */
+	ret = mi_lttng_writer_open_element(writer, mi_lttng_element_trigger);
+	if (ret) {
+		goto mi_error;
+	}
+
+	trigger_status = lttng_trigger_get_owner_uid(trigger, &owner_uid);
+	LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
+
+	/* Name. */
+	ret = mi_lttng_writer_write_element_string(
+			writer, config_element_name, trigger->name);
+	if (ret) {
+		goto mi_error;
+	}
+
+	/* Owner uid. */
+	ret = mi_lttng_writer_write_element_signed_int(writer,
+			mi_lttng_element_trigger_owner_uid,
+			(int64_t) owner_uid);
+	if (ret) {
+		goto mi_error;
+	}
+
+	/* Condition. */
+	condition = lttng_trigger_get_const_condition(trigger);
+	LTTNG_ASSERT(condition);
+	ret_code = lttng_condition_mi_serialize(
+			trigger, condition, writer, error_query_callbacks);
+	if (ret_code != LTTNG_OK) {
+		goto end;
+	}
+
+	/* Action. */
+	action = lttng_trigger_get_const_action(trigger);
+	LTTNG_ASSERT(action);
+	ret_code = lttng_action_mi_serialize(trigger, action, writer,
+			error_query_callbacks, &action_path_indexes);
+	if (ret_code != LTTNG_OK) {
+		goto end;
+	}
+
+	if (error_query_callbacks && error_query_callbacks->trigger_cb) {
+		struct lttng_error_query_results *results = NULL;
+
+		ret_code = error_query_callbacks->trigger_cb(trigger, &results);
+		if (ret_code != LTTNG_OK) {
+			goto end;
+		}
+
+		ret_code = lttng_error_query_results_mi_serialize(
+				results, writer);
+		lttng_error_query_results_destroy(results);
+		if (ret_code != LTTNG_OK) {
+			goto end;
+		}
+	}
+
+	/* Close trigger element. */
+	ret = mi_lttng_writer_close_element(writer);
+	if (ret) {
+		goto mi_error;
+	}
+
+	ret_code = LTTNG_OK;
+	goto end;
+
+mi_error:
+	ret_code = LTTNG_ERR_MI_IO_FAIL;
+end:
+	lttng_dynamic_array_reset(&action_path_indexes);
+	return ret_code;
+}
+
+/* Used by qsort, which expects the semantics of strcmp(). */
+static int compare_triggers_by_name(const void *a, const void *b)
+{
+	const struct lttng_trigger *trigger_a =
+			*((const struct lttng_trigger **) a);
+	const struct lttng_trigger *trigger_b =
+			*((const struct lttng_trigger **) b);
+	const char *name_a, *name_b;
+	enum lttng_trigger_status trigger_status;
+
+	/* Anonymous triggers are not reachable here. */
+	trigger_status = lttng_trigger_get_name(trigger_a, &name_a);
+	LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
+
+	trigger_status = lttng_trigger_get_name(trigger_b, &name_b);
+	LTTNG_ASSERT(trigger_status == LTTNG_TRIGGER_STATUS_OK);
+
+	return strcmp(name_a, name_b);
+}
+
+LTTNG_HIDDEN
+enum lttng_error_code lttng_triggers_mi_serialize(const struct lttng_triggers *triggers,
+		struct mi_writer *writer,
+		const struct mi_lttng_error_query_callbacks
+				*error_query_callbacks)
+{
+	int ret;
+	enum lttng_error_code ret_code;
+	enum lttng_trigger_status status;
+	unsigned int count, i;
+	struct lttng_dynamic_pointer_array sorted_triggers;
+
+	LTTNG_ASSERT(triggers);
+	LTTNG_ASSERT(writer);
+
+	/*
+	 * Sort trigger by name to ensure an order at the MI level and ignore
+	 * any anonymous trigger present.
+	 */
+	lttng_dynamic_pointer_array_init(&sorted_triggers, NULL);
+
+	status = lttng_triggers_get_count(triggers, &count);
+	LTTNG_ASSERT(status == LTTNG_TRIGGER_STATUS_OK);
+
+	for (i = 0; i < count; i++) {
+		int add_ret;
+		const char *unused_name;
+		const struct lttng_trigger *trigger =
+				lttng_triggers_get_at_index(triggers, i);
+
+		status = lttng_trigger_get_name(trigger, &unused_name);
+		switch (status) {
+		case LTTNG_TRIGGER_STATUS_OK:
+			break;
+		case LTTNG_TRIGGER_STATUS_UNSET:
+			/* Don't list anonymous triggers. */
+			continue;
+		default:
+			abort();
+		}
+
+		add_ret = lttng_dynamic_pointer_array_add_pointer(
+				&sorted_triggers, (void *) trigger);
+
+		if (add_ret) {
+			ERR("Failed to lttng_trigger to sorting array.");
+			ret_code = LTTNG_ERR_NOMEM;
+			goto error;
+		}
+	}
+
+	qsort(sorted_triggers.array.buffer.data, count,
+			sizeof(struct lttng_trigger *),
+			compare_triggers_by_name);
+
+	/* Open triggers element. */
+	ret = mi_lttng_writer_open_element(writer, mi_lttng_element_triggers);
+	if (ret) {
+		ret_code = LTTNG_ERR_MI_IO_FAIL;
+		goto error;
+	}
+
+	for (i = 0; i < lttng_dynamic_pointer_array_get_count(&sorted_triggers); i++) {
+		const struct lttng_trigger *trigger =
+				(const struct lttng_trigger *)
+				lttng_dynamic_pointer_array_get_pointer(
+						&sorted_triggers, i);
+
+		lttng_trigger_mi_serialize(trigger, writer, error_query_callbacks);
+	}
+
+	/* Close triggers element. */
+	ret = mi_lttng_writer_close_element(writer);
+	if (ret) {
+		ret_code = LTTNG_ERR_MI_IO_FAIL;
+		goto error;
+	}
+
+	ret_code = LTTNG_OK;
+
+error:
+	lttng_dynamic_pointer_array_reset(&sorted_triggers);
+	return ret_code;
+}