From 072391fccbd052334dbd836d451f2be0a74a0685 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@systemlinux.org>
Date: Sun, 31 Mar 2013 15:34:50 +0000
Subject: [PATCH] buffer_tree: Improve btr_splice_out_node().

This changes btr_splice_out_node() to take a pointer to a btrn, just
like btr_remove_node(). This allows to set the variable to NULL after
the node has been spliced out. The callers are updated accordingly.
---
 amp_filter.c       | 2 +-
 buffer_tree.c      | 8 ++++----
 buffer_tree.h      | 2 +-
 prebuffer_filter.c | 2 +-
 wav_filter.c       | 2 +-
 5 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/amp_filter.c b/amp_filter.c
index dddc0a85..b0f36872 100644
--- a/amp_filter.c
+++ b/amp_filter.c
@@ -73,7 +73,7 @@ static int amp_post_select(__a_unused struct sched *s, struct task *t)
 	bool inplace = btr_inplace_ok(btrn);
 
 	if (pad->amp == 0) { /* no amplification */
-		btr_splice_out_node(btrn);
+		btr_splice_out_node(&fn->btrn);
 		return -E_AMP_ZERO_AMP;
 	}
 next_buffer:
diff --git a/buffer_tree.c b/buffer_tree.c
index b1eeb036..84dc933a 100644
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -835,7 +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
@@ -843,9 +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);
@@ -862,7 +862,7 @@ void btr_splice_out_node(struct btr_node *btrn)
 			list_del(&ch->node);
 	}
 	assert(list_empty(&btrn->children));
-	btrn->parent = NULL;
+	*btrnp = NULL;
 }
 
 /**
diff --git a/buffer_tree.h b/buffer_tree.h
index 20dcd62d..6127dd92 100644
--- a/buffer_tree.h
+++ b/buffer_tree.h
@@ -192,7 +192,7 @@ size_t btr_next_buffer(struct btr_node *btrn, char **bufp);
 size_t btr_next_buffer_omit(struct btr_node *btrn, size_t omit, char **bufp);
 void btr_consume(struct btr_node *btrn, size_t numbytes);
 int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result);
-void btr_splice_out_node(struct btr_node *btrn);
+void btr_splice_out_node(struct btr_node **btrnp);
 void btr_pushdown(struct btr_node *btrn);
 void *btr_context(struct btr_node *btrn);
 void btr_merge(struct btr_node *btrn, size_t dest_size);
diff --git a/prebuffer_filter.c b/prebuffer_filter.c
index 655c981b..f4ef76e2 100644
--- a/prebuffer_filter.c
+++ b/prebuffer_filter.c
@@ -70,7 +70,7 @@ static int prebuffer_post_select(__a_unused struct sched *s, struct task *t)
 		return 0;
 	if (iqs < conf->size_arg)
 		return 0;
-	btr_splice_out_node(fn->btrn);
+	btr_splice_out_node(&fn->btrn);
 	return -E_PREBUFFER_SUCCESS;
 }
 
diff --git a/wav_filter.c b/wav_filter.c
index 83b81fb2..eaef1f5c 100644
--- a/wav_filter.c
+++ b/wav_filter.c
@@ -113,7 +113,7 @@ static int wav_post_select(__a_unused struct sched *s, struct task *t)
 	ret = -E_WAV_SUCCESS;
 err:
 	if (ret == -E_WAV_SUCCESS)
-		btr_splice_out_node(btrn);
+		btr_splice_out_node(&fn->btrn);
 	else {
 		btr_remove_node(&fn->btrn);
 		PARA_ERROR_LOG("%s\n", para_strerror(-ret));
-- 
2.39.5