TCUuidList, refactor traits

lib/taskchampion.h

@@ -148,6 +148,27 @@ typedef struct TCUuid {
   uint8_t bytes[16];
 } TCUuid;
 
+/**
+ * TCUuidList represents a list of uuids.
+ *
+ * The content of this struct must be treated as read-only.
+ */
+typedef struct TCUuidList {
+  /**
+   * number of uuids in items
+   */
+  size_t len;
+  /**
+   * total size of items (internal use only)
+   */
+  size_t _capacity;
+  /**
+   * array of uuids. these remain owned by the TCUuidList instance and will be freed by
+   * tc_uuid_list_free.  This pointer is never NULL for a valid TCUuidList.
+   */
+  const struct TCUuid *items;
+} TCUuidList;
+
 /**
  * TCStringList represents a list of strings.
  *
@@ -193,6 +214,13 @@ struct TCReplica *tc_replica_new_on_disk(struct TCString *path, struct TCString
  */
 struct TCTaskList tc_replica_all_tasks(struct TCReplica *rep);
 
+/**
+ * Get a list of all uuids for tasks in the replica.
+ *
+ * Returns a TCUuidList with a NULL items field on error.
+ */
+struct TCUuidList tc_replica_all_task_uuids(struct TCReplica *rep);
+
 /**
  * Get an existing task by its UUID.
  *
@@ -498,6 +526,14 @@ struct TCString *tc_uuid_to_str(struct TCUuid tcuuid);
  */
 TCResult tc_uuid_from_str(struct TCString *s, struct TCUuid *uuid_out);
 
+/**
+ * Free a TCUuidList instance.  The instance, and all TCUuids it contains, must not be used after
+ * this call.
+ *
+ * When this call returns, the `items` pointer will be NULL, signalling an invalid TCUuidList.
+ */
+void tc_uuid_list_free(struct TCUuidList *tcuuids);
+
 #ifdef __cplusplus
 } // extern "C"
 #endif // __cplusplus