Add client notification API

[lttng-tools.git] / src / common / trigger.c

diff --git a/src/common/trigger.c b/src/common/trigger.c
new file mode 100644 (file)
index 0000000..13f26d6
--- /dev/null
+++ b/src/common/trigger.c
@@ -0,0 +1,183 @@
+/*
+ * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <lttng/trigger/trigger-internal.h>
+#include <lttng/condition/condition-internal.h>
+#include <lttng/action/action-internal.h>
+#include <common/error.h>
+#include <assert.h>
+
+LTTNG_HIDDEN
+bool lttng_trigger_validate(struct lttng_trigger *trigger)
+{
+       bool valid;
+
+       if (!trigger) {
+               valid = false;
+               goto end;
+       }
+
+       valid = lttng_condition_validate(trigger->condition) &&
+                       lttng_action_validate(trigger->action);
+end:
+       return valid;
+}
+
+struct lttng_trigger *lttng_trigger_create(
+               struct lttng_condition *condition,
+               struct lttng_action *action)
+{
+       struct lttng_trigger *trigger = NULL;
+
+       if (!condition || !action) {
+               goto end;
+       }
+
+       trigger = zmalloc(sizeof(struct lttng_trigger));
+       if (!trigger) {
+               goto end;
+       }
+
+       trigger->condition = condition;
+       trigger->action = action;
+end:
+       return trigger;
+}
+
+struct lttng_condition *lttng_trigger_get_condition(
+               struct lttng_trigger *trigger)
+{
+       return trigger ? trigger->condition : NULL;
+}
+
+extern struct lttng_action *lttng_trigger_get_action(
+               struct lttng_trigger *trigger)
+{
+       return trigger ? trigger->action : NULL;
+}
+
+void lttng_trigger_destroy(struct lttng_trigger *trigger)
+{
+       if (!trigger) {
+               return;
+       }
+
+       free(trigger);
+}
+
+LTTNG_HIDDEN
+ssize_t lttng_trigger_create_from_buffer(
+               const struct lttng_buffer_view *src_view,
+               struct lttng_trigger **trigger)
+{
+       ssize_t ret, offset = 0, condition_size, action_size;
+       struct lttng_condition *condition = NULL;
+       struct lttng_action *action = NULL;
+       const struct lttng_trigger_comm *trigger_comm;
+       struct lttng_buffer_view condition_view;
+       struct lttng_buffer_view action_view;
+
+       if (!src_view || !trigger) {
+               ret = -1;
+               goto end;
+       }
+
+       /* lttng_trigger_comm header */
+       trigger_comm = (const struct lttng_trigger_comm *) src_view->data;
+       offset += sizeof(*trigger_comm);
+
+       condition_view = lttng_buffer_view_from_view(src_view, offset, -1);
+
+       /* struct lttng_condition */
+       condition_size = lttng_condition_create_from_buffer(&condition_view,
+                       &condition);
+       if (condition_size < 0) {
+               ret = condition_size;
+               goto end;
+       }
+       offset += condition_size;
+
+       /* struct lttng_action */
+       action_view = lttng_buffer_view_from_view(src_view, offset, -1);
+       action_size = lttng_action_create_from_buffer(&action_view, &action);
+       if (action_size < 0) {
+               ret = action_size;
+               goto end;
+       }
+       offset += action_size;
+
+       /* Unexpected size of inner-elements; the buffer is corrupted. */
+       if ((ssize_t) trigger_comm->length != condition_size + action_size) {
+               ret = -1;
+               goto error;
+       }
+
+       *trigger = lttng_trigger_create(condition, action);
+       if (!*trigger) {
+               ret = -1;
+               goto error;
+       }
+       ret = offset;
+end:
+       return ret;
+error:
+       lttng_condition_destroy(condition);
+       lttng_action_destroy(action);
+       return ret;
+}
+
+/*
+ * Returns the size of a trigger (header + condition + action).
+ * Both elements are stored contiguously, see their "*_comm" structure
+ * for the detailed format.
+ */
+LTTNG_HIDDEN
+ssize_t lttng_trigger_serialize(struct lttng_trigger *trigger, char *buf)
+{
+       struct lttng_trigger_comm trigger_comm;
+       ssize_t action_size, condition_size, offset = 0, ret;
+
+       if (!trigger) {
+               ret = -1;
+               goto end;
+       }
+
+       offset += sizeof(trigger_comm);
+       condition_size = lttng_condition_serialize(trigger->condition,
+                       buf ? (buf + offset) : NULL);
+       if (condition_size < 0) {
+               ret = -1;
+               goto end;
+       }
+       offset += condition_size;
+
+       action_size = lttng_action_serialize(trigger->action,
+                       buf ? (buf + offset) : NULL);
+       if (action_size < 0) {
+               ret = -1;
+               goto end;
+       }
+       offset += action_size;
+
+       if (buf) {
+               trigger_comm.length = (uint32_t) (condition_size + action_size);
+               memcpy(buf, &trigger_comm, sizeof(trigger_comm));
+       }
+       ret = offset;
+end:
+       return ret;
+}