+ varlen_data = zmalloc(lsm.u.disable.bytecode_len
+ + lsm.u.disable.expression_len);
+ if (!varlen_data) {
+ ret = -LTTNG_ERR_EXCLUSION_NOMEM;
+ goto mem_error;
+ }
+
+ /* Add filter expression. */
+ if (lsm.u.disable.expression_len != 0) {
+ memcpy(varlen_data,
+ filter_expression,
+ lsm.u.disable.expression_len);
+ }
+ /* Add filter bytecode next. */
+ if (ctx && lsm.u.disable.bytecode_len != 0) {
+ memcpy(varlen_data
+ + lsm.u.disable.expression_len,
+ &ctx->bytecode->b,
+ lsm.u.disable.bytecode_len);
+ }
+
+ ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, varlen_data,
+ lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL);
+ free(varlen_data);
+
+mem_error:
+ if (filter_expression && ctx) {
+ filter_bytecode_free(ctx);
+ filter_ir_free(ctx);
+ filter_parser_ctx_free(ctx);
+ }
+filter_error:
+ if (free_filter_expression) {
+ /*
+ * The filter expression has been replaced and must be freed as
+ * it is not the original filter expression received as a
+ * parameter.
+ */
+ free(filter_expression);
+ }
+error:
+ /*
+ * Return directly to the caller and don't ask the sessiond since
+ * something went wrong in the parsing of data above.
+ */
+ return ret;
+
+ask_sessiond:
+ ret = lttng_ctl_ask_sessiond(&lsm, NULL);
+ return ret;
+}
+
+/*
+ * Disable event(s) of a channel and domain.
+ * If no event name is specified, all events are disabled.
+ * If no channel name is specified, the default 'channel0' is used.
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_disable_event(struct lttng_handle *handle, const char *name,
+ const char *channel_name)
+{
+ struct lttng_event ev;
+
+ memset(&ev, 0, sizeof(ev));
+ ev.loglevel = -1;
+ ev.type = LTTNG_EVENT_ALL;
+ lttng_ctl_copy_string(ev.name, name, sizeof(ev.name));
+ return lttng_disable_event_ext(handle, &ev, channel_name, NULL);
+}
+
+/*
+ * Enable channel per domain
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_enable_channel(struct lttng_handle *handle,
+ struct lttng_channel *chan)
+{
+ struct lttcomm_session_msg lsm;
+
+ /* NULL arguments are forbidden. No default values. */
+ if (handle == NULL || chan == NULL) {
+ return -LTTNG_ERR_INVALID;
+ }
+
+ memset(&lsm, 0, sizeof(lsm));
+
+ memcpy(&lsm.u.channel.chan, chan, sizeof(lsm.u.channel.chan));
+
+ lsm.cmd_type = LTTNG_ENABLE_CHANNEL;
+
+ lttng_ctl_copy_lttng_domain(&lsm.domain, &handle->domain);
+
+ lttng_ctl_copy_string(lsm.session.name, handle->session_name,
+ sizeof(lsm.session.name));
+
+ return lttng_ctl_ask_sessiond(&lsm, NULL);
+}
+
+/*
+ * All tracing will be stopped for registered events of the channel.
+ * Returns size of returned session payload data or a negative error code.
+ */
+int lttng_disable_channel(struct lttng_handle *handle, const char *name)
+{
+ struct lttcomm_session_msg lsm;
+
+ /* Safety check. Both are mandatory. */
+ if (handle == NULL || name == NULL) {
+ return -LTTNG_ERR_INVALID;