buffer_tree: Improve btr_splice_out_node().

[paraslash.git] / buffer_tree.c

diff --git a/buffer_tree.c b/buffer_tree.c
index 63be36d7a10042c5f21b6a95677cdea369ffa12c..84dc933a037c7552db6fdd7559ea096c2f892ae1 100644 (file)
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009-2012 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2009-2013 Andre Noll <maan@systemlinux.org>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
@@ -295,9 +295,10 @@ struct btr_node *btr_new_node(struct btr_node_description *bnd)
                bnd->child->parent = btrn;
                goto out;
        }
-       PARA_EMERG_LOG("inserting internal nodes not yet supported.\n");
-       exit(EXIT_FAILURE);
-       assert(bnd->child->parent == bnd->parent);
+       list_add_tail(&btrn->node, &bnd->parent->children);
+       list_move(&bnd->child->node, &btrn->children);
+       bnd->child->parent = btrn;
+       PARA_INFO_LOG("added %s as internal node\n", bnd->name);
 out:
        return btrn;
 }
@@ -385,7 +386,8 @@ void btr_add_output(char *buf, size_t size, struct btr_node *btrn)
 {
        struct btr_buffer *btrb;
 
-       assert(size != 0);
+       if (size == 0)
+               return;
        if (list_empty(&btrn->children)) {
                free(buf);
                return;
@@ -414,7 +416,8 @@ void btr_add_output_dont_free(const char *buf, size_t size, struct btr_node *btr
 {
        struct btr_buffer *btrb;
 
-       assert(size != 0);
+       if (size == 0)
+               return;
        if (list_empty(&btrn->children))
                return;
        btrb = new_btrb((char *)buf, size);
@@ -441,7 +444,8 @@ void btr_add_output_pool(struct btr_pool *btrp, size_t size,
        char *buf;
        size_t avail;
 
-       assert(size != 0);
+       if (size == 0)
+               return;
        if (list_empty(&btrn->children))
                return;
        avail = btr_pool_get_buffer(btrp, &buf);
@@ -540,14 +544,16 @@ static bool btr_no_children(struct btr_node *btrn)
 }
 
 /**
- * Find out whether a node is an orphan node.
+ * Find out whether a node is an orphan.
  *
  * \param btrn The buffer tree node.
  *
  * \return True if \a btrn has no parent.
  *
- * This function will always return true for the root node.  However in case
- * nodes have been removed from the tree, other nodes may become orphans too.
+ * This function returns true for the root node and false for any other node.
+ *
+ * After a (non-leaf) node was removed removed from the tree, the function
+ * returns true for all child nodes.
  */
 bool btr_no_parent(struct btr_node *btrn)
 {
@@ -829,7 +835,7 @@ size_t btr_get_input_queue_size(struct btr_node *btrn)
 /**
  * Remove a node from the buffer tree, reconnecting parent and children.
  *
- * \param btrn The node to splice out.
+ * \param btrnp The node to splice out.
  *
  * This function is used by buffer tree nodes that do not exist during the
  * whole lifetime of the buffer tree. Unlike btr_remove_node(), calling
@@ -837,9 +843,9 @@ size_t btr_get_input_queue_size(struct btr_node *btrn)
  * but reconnects the buffer tree by making all child nodes of \a btrn children
  * of the parent of \a btrn.
  */
-void btr_splice_out_node(struct btr_node *btrn)
+void btr_splice_out_node(struct btr_node **btrnp)
 {
-       struct btr_node *ch, *tmp;
+       struct btr_node *btrn = *btrnp, *ch, *tmp;
 
        assert(btrn);
        PARA_NOTICE_LOG("splicing out %s\n", btrn->name);
@@ -852,9 +858,11 @@ void btr_splice_out_node(struct btr_node *btrn)
                ch->parent = btrn->parent;
                if (btrn->parent)
                        list_move(&ch->node, &btrn->parent->children);
+               else
+                       list_del(&ch->node);
        }
        assert(list_empty(&btrn->children));
-       btrn->parent = NULL;
+       *btrnp = NULL;
 }
 
 /**
@@ -1225,3 +1233,18 @@ void btr_get_node_start(struct btr_node *btrn, struct timeval *tv)
 {
        *tv = btrn->start;
 }
+
+/**
+ * Get the parent node of a buffer tree node.
+ *
+ * \param btrn The node whose parent should be returned.
+ *
+ * \a btrn must not be \p NULL.
+ *
+ * \return The parent of \a btrn, or \p NULL if \a btrn is the
+ * root node of the buffer tree.
+ */
+struct btr_node *btr_parent(struct btr_node *btrn)
+{
+       return btrn->parent;
+}