doc

[protos/libecoli.git] / lib / ecoli_node_weakref.h

diff --git a/lib/ecoli_node_weakref.h b/lib/ecoli_node_weakref.h
index c29799f..cb2aed1 100644 (file)
--- a/lib/ecoli_node_weakref.h
+++ b/lib/ecoli_node_weakref.h
@@ -1,52 +1,27 @@
-/*
- * Copyright (c) 2016, Olivier MATZ <zer0@droids-corp.org>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- *
- *     * Redistributions of source code must retain the above copyright
- *       notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above copyright
- *       notice, this list of conditions and the following disclaimer in the
- *       documentation and/or other materials provided with the distribution.
- *     * Neither the name of the University of California, Berkeley nor the
- *       names of its contributors may be used to endorse or promote products
- *       derived from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2016, Olivier MATZ <zer0@droids-corp.org>
  */
 
-#ifndef ECOLI_NODE_BYPASS_
-#define ECOLI_NODE_BYPASS_
+#ifndef ECOLI_NODE_WEAKREF_
+#define ECOLI_NODE_WEAKREF_
 
 #include <ecoli_node.h>
 
-/* a node that just behaves like its child and that does not free
- * its child when freed.
+/* A node that just behaves like its child and that does not free
+ * its child when freed. **The child has to be freed manually**.
  *
  * useful to create cyclic graphs of nodes:
  *   creating a loop (with clones) result in something that is not
  *   freeable, due to reference counters
  *
  * Example:
+ *  expr = or()
  *  val = int(0, 10)
  *  op = str("!")
- *  expr = or()
- *  seq = seq(clone(op), clone(expr))
- *  expr.add(clone(seq))
- *  expr.add(clone(val))
- *  free(val)
- *  free(op)
- *  free(seq)
+ *  seq = seq(op, clone(expr))
+ *  expr.add(seq)
+ *  expr.add(val)
+ *  free(expr) // just decrease ref
  *
  * FAIL: expr cannot be freed due to cyclic refs
  * The references are like this:
@@ -54,27 +29,23 @@
  *                   val
  *                    ^
  *                    |
- *        $user ---> expr ---> seq ---> op
+ *     $user ~ ~ ~ > expr ---> seq ---> op
  *                        <---
  *
  * It is solved with:
+ *  expr = or()
  *  val = int(0, 10)
  *  op = str("!")
- *  expr = or()
  *  weak = weak(expr)
- *  seq = seq(clone(op), clone(weak))
- *  expr.add(clone(seq))
- *  expr.add(clone(val))
- *  free(val)
- *  free(op)
- *  free(weak)
- *  free(seq)
+ *  seq = seq(op, weak)
+ *  expr.add(op)
+ *  expr.add(val)
  *
  *
  *                   val
  *                    ^
  *                    |
- *        $user ---> expr ---------------> seq ---> op
+ *     $user ~ ~ ~ > expr ---------------> seq ---> op
  *                        <- - - weak <---
  *
  * The node expr can be freed.
@@ -83,8 +54,6 @@
 /* on error, child is *not* freed */
 struct ec_node *ec_node_weakref(const char *id, struct ec_node *child);
 
-struct ec_node *ec_node_weakref_empty(const char *id);
-
 /* on error, child is *not* freed */
 int ec_node_weakref_set(struct ec_node *node, struct ec_node *child);