+ for (i = 0; i < count; i++) {
+ if (channel_name != NULL) {
+ if (strncmp(channels[i].name, channel_name, NAME_MAX) == 0) {
+ chan_found = 1;
+ } else {
+ continue;
+ }
+ }
+
+ /* Write channel element and leave it open */
+ ret = mi_lttng_channel(writer, &channels[i], 1);
+ if (ret) {
+ goto error;
+ }
+
+ /* Listing events per channel */
+ ret = list_events(channels[i].name);
+ if (ret) {
+ goto error;
+ }
+
+ /* Closing the channel element we opened earlier */
+ ret = mi_lttng_writer_close_element(writer);
+ if (ret) {
+ goto error;
+ }
+
+ if (chan_found) {
+ break;
+ }
+ }
+
+ /* Close channels element */
+ ret = mi_lttng_writer_close_element(writer);
+ if (ret) {
+ goto error;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * List channel(s) of session and domain.
+ *
+ * If channel_name is NULL, all channels are listed.
+ */
+static int list_channels(const char *channel_name)
+{
+ int count, i, ret = CMD_SUCCESS;
+ unsigned int chan_found = 0;
+ struct lttng_channel *channels = NULL;
+
+ DBG("Listing channel(s) (%s)", channel_name ? : "<all>");
+
+ count = lttng_list_channels(handle, &channels);
+ if (count < 0) {
+ switch (-count) {
+ case LTTNG_ERR_KERN_CHAN_NOT_FOUND:
+ if (lttng_opt_mi) {
+ /* When printing mi this is not an error
+ * but an empty channels element */
+ count = 0;
+ } else {
+ ret = CMD_SUCCESS;
+ WARN("No kernel channel");
+ goto error_channels;
+ }
+ break;
+ default:
+ /* We had a real error */
+ ret = CMD_ERROR;
+ ERR("%s", lttng_strerror(count));
+ goto error_channels;
+ break;
+ }
+ }
+
+ if (lttng_opt_mi) {
+ /* Mi print */
+ ret = mi_list_channels(channels, count, channel_name);
+ if (ret) {
+ ret = CMD_ERROR;
+ goto error;
+ }
+ } else {
+ /* Pretty print */
+ if (channel_name == NULL) {
+ MSG("Channels:\n-------------");
+ }
+
+ for (i = 0; i < count; i++) {
+ if (channel_name != NULL) {
+ if (strncmp(channels[i].name, channel_name, NAME_MAX) == 0) {
+ chan_found = 1;
+ } else {
+ continue;
+ }
+ }
+ print_channel(&channels[i]);
+
+ /* Listing events per channel */
+ ret = list_events(channels[i].name);
+ if (ret) {
+ goto error;
+ }
+
+ if (chan_found) {
+ break;
+ }
+ }
+
+ if (!chan_found && channel_name != NULL) {
+ ret = CMD_ERROR;
+ ERR("Channel %s not found", channel_name);
+ goto error;
+ }
+ }
+error:
+ free(channels);
+
+error_channels:
+ return ret;
+}
+
+/*
+ * Machine interface
+ * Find the session with session_name as name
+ * and print his informations.
+ */
+static int mi_list_session(const char *session_name,
+ struct lttng_session *sessions, int count)
+{
+ int ret, i;
+ unsigned int session_found = 0;
+