X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=buffer_tree.c;h=c62cbf13c3bdc4b621bd891d41e1b74fe24d98fe;hp=5b4ce19e5f774fd8aaf67fdc42592339f1fb81ac;hb=6d9c357ff64e799dfeacda6a176012de10c7f5c1;hpb=1cefe6a503c74d609db4e99e689d46575a5e40fd

diff --git a/buffer_tree.c b/buffer_tree.c
index 5b4ce19e..c62cbf13 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -30,6 +30,8 @@ struct btr_buffer {
 	int refcount;
 	/* NULL means no buffer pool but a malloced buffer. */
 	struct btr_pool *pool;
+	/* Only relevant if pool is NULL. */
+	bool dont_free;
 };
 
 struct btr_buffer_reference {
@@ -319,7 +321,7 @@ static void dealloc_buffer(struct btr_buffer *btrb)
 {
 	if (btrb->pool)
 		btr_pool_deallocate(btrb->pool, btrb->size);
-	else
+	else if (!btrb->dont_free)
 		free(btrb->buf);
 }
 
@@ -392,6 +394,34 @@ void btr_add_output(char *buf, size_t size, struct btr_node *btrn)
 	add_btrb_to_children(btrb, btrn, 0);
 }
 
+/**
+ * Insert a buffer into the buffer tree, non-freeing variant.
+ *
+ * \param buf See \ref btr_add_output().
+ * \param size See \ref btr_add_output().
+ * \param btrn See \ref btr_add_output().
+ *
+ * This is similar to btr_add_output() but additionally sets the \p dont_free
+ * flag on \a buf. If the refcount for the buffer drops to zero, \a buf will
+ * not be deallocated if this flag is set.
+ *
+ * The \p dont_free bit also prevents the children of \a btrn from modifying
+ * the buffer contents inplace. Specifically, \ref btr_inplace_ok() returns
+ * false if there is any buffer in the input queue with the \p dont_free bit
+ * set.
+ */
+void btr_add_output_dont_free(const char *buf, size_t size, struct btr_node *btrn)
+{
+	struct btr_buffer *btrb;
+
+	assert(size != 0);
+	if (list_empty(&btrn->children))
+		return;
+	btrb = new_btrb((char *)buf, size);
+	btrb->dont_free = true;
+	add_btrb_to_children(btrb, btrn, 0);
+}
+
 /**
  * Feed data to child nodes of a buffer tree node.
  *
@@ -544,9 +574,15 @@ bool btr_no_parent(struct btr_node *btrn)
  */
 bool btr_inplace_ok(struct btr_node *btrn)
 {
-	if (!btrn->parent)
-		return true;
-	return list_is_singular(&btrn->parent->children);
+	struct btr_buffer_reference *br;
+	FOR_EACH_BUFFER_REF(br, btrn) {
+		struct btr_buffer *btrb = br->btrb;
+		if (btrb->refcount > 1)
+			return false;
+		if (btrb->dont_free == true)
+			return false;
+	}
+	return true;
 }
 
 static inline size_t br_available_bytes(struct btr_buffer_reference *br)
@@ -729,44 +765,37 @@ void btr_drain(struct btr_node *btrn)
 		btr_drop_buffer_reference(br);
 }
 
-/**
- * Free all resources allocated by btr_new_node().
- *
- * \param btrn Pointer to a btr node obtained by \ref btr_new_node().
- *
- * Like free(3), it is OK to call this with a \p NULL pointer argument.
- */
-void btr_free_node(struct btr_node *btrn)
-{
-	if (!btrn)
-		return;
-	free(btrn->name);
-	free(btrn);
-}
-
 /**
  * Remove a node from a buffer tree.
  *
- * \param btrn The node to remove.
+ * \param btrnp Determines the node to remove.
  *
- * This makes all child nodes of \a btrn orphans and removes \a btrn from the
- * list of children of its parent. Moreover, the input queue of \a btrn is
- * flushed if it is not empty.
+ * This orphans all children of the node given by \a btrnp and removes this
+ * node from the child list of its parent. Moreover, the input queue is flushed
+ * and the node pointer given by \a btrp is set to \p NULL.
  *
  * \sa \ref btr_splice_out_node.
  */
-void btr_remove_node(struct btr_node *btrn)
+void btr_remove_node(struct btr_node **btrnp)
 {
 	struct btr_node *ch;
+	struct btr_node *btrn;
 
-	if (!btrn)
+	if (!btrnp)
 		return;
-	PARA_NOTICE_LOG("removing btr node %s from buffer tree\n", btrn->name);
+	btrn = *btrnp;
+	if (!btrn)
+		goto out;
+	PARA_INFO_LOG("removing btr node %s from buffer tree\n", btrn->name);
 	FOR_EACH_CHILD(ch, btrn)
 		ch->parent = NULL;
 	btr_drain(btrn);
 	if (btrn->parent)
 		list_del(&btrn->node);
+	free(btrn->name);
+	free(btrn);
+out:
+	*btrnp = NULL;
 }
 
 /**
@@ -825,6 +854,7 @@ void btr_splice_out_node(struct btr_node *btrn)
 			list_move(&ch->node, &btrn->parent->children);
 	}
 	assert(list_empty(&btrn->children));
+	btrn->parent = NULL;
 }
 
 /**
@@ -878,7 +908,7 @@ int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
 		if (ret < 0)
 			return ret;
 		if (value_result && *value_result)
-			PARA_NOTICE_LOG("%s(%s): %s\n", command, parent->name,
+			PARA_INFO_LOG("%s(%s): %s\n", command, parent->name,
 				*value_result);
 		return 1;
 	}