Add Read TOC (0x43) Command Support (and basic testcase).

lib/scsi-command.c

@@ -1477,6 +1477,28 @@ iscsi_get_user_in_buffer(struct iscsi_context *iscsi, struct iscsi_in_pdu *in, u
 	return scsi_task_get_data_in_buffer(pdu->scsi_cbdata->task, offset + pos, count);
 }
 
+struct scsi_task *
+iscsi_readtoc_task(struct iscsi_context *iscsi, int lun, int msf,
+		   int format, int track_session, int maxsize,
+		   iscsi_command_cb cb, void *private_data)
+{
+	struct scsi_task *task;
+
+	task = scsi_cdb_readtoc(msf, format, track_session, maxsize);
+	if (task == NULL) {
+		iscsi_set_error(iscsi, "Out-of-memory: Failed to create "
+				"read TOC cdb.");
+		return NULL;
+	}
+	if (iscsi_scsi_command_async(iscsi, lun, task, cb, NULL,
+				     private_data) != 0) {
+		scsi_free_scsi_task(task);
+		return NULL;
+	}
+
+	return task;
+}
+
 struct scsi_task *
 iscsi_scsi_get_task_from_pdu(struct iscsi_pdu *pdu)
 {