[btr] Split btr_del_node() into two functions.

[paraslash.git] / buffer_tree.c

diff --git a/buffer_tree.c b/buffer_tree.c
index b7420ebeeb38e70f85ad4c9f34fa215b59504f61..022a4118a76d0191d197b5cda6bc64b77eff924c 100644 (file)
--- a/buffer_tree.c
+++ b/buffer_tree.c
@@ -119,6 +119,11 @@ void btr_add_output(char *buf, size_t size, struct btr_node *btrn)
 {
        struct btr_buffer *btrb;
 
+       assert(size != 0);
+       if (list_empty(&btrn->children)) {
+               free(buf);
+               return;
+       }
        btrb = new_btrb(buf, size);
        add_btrb_to_children(btrb, btrn, 0);
 }
@@ -137,6 +142,17 @@ void btr_pushdown(struct btr_node *btrn)
                btr_pushdown_br(br, btrn);
 }
 
+int btr_pushdown_one(struct btr_node *btrn)
+{
+       struct btr_buffer_reference *br;
+
+       if (list_empty(&btrn->input_queue))
+               return 0;
+       br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
+       btr_pushdown_br(br, btrn);
+       return 1;
+}
+
 /* Return true if this node has no children. */
 bool btr_no_children(struct btr_node *btrn)
 {
@@ -166,6 +182,9 @@ size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char **buf)
        return br_available_bytes(br);
 }
 
+/**
+ * \return zero if the input buffer queue is empty.
+ */
 size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
 {
        struct btr_buffer_reference *br;
@@ -197,20 +216,26 @@ static void flush_input_queue(struct btr_node *btrn)
                btr_drop_buffer_reference(br);
 }
 
-void btr_del_node(struct btr_node *btrn)
+void btr_free_node(struct btr_node *btrn)
+{
+       if (!btrn)
+               return;
+       free(btrn->name);
+       free(btrn);
+}
+
+void btr_remove_node(struct btr_node *btrn)
 {
        struct btr_node *ch;
 
        if (!btrn)
                return;
-       PARA_NOTICE_LOG("deleting %s\n", btrn->name);
+       PARA_NOTICE_LOG("removing btr node %s from buffer tree\n", btrn->name);
        FOR_EACH_CHILD(ch, btrn)
                ch->parent = NULL;
        flush_input_queue(btrn);
        if (btrn->parent)
                list_del(&btrn->node);
-       free(btrn->name);
-       free(btrn);
 }
 
 size_t btr_get_input_queue_size(struct btr_node *btrn)
@@ -242,9 +267,6 @@ void btr_splice_out_node(struct btr_node *btrn)
                        list_move(&ch->node, &btrn->parent->children);
        }
        assert(list_empty(&btrn->children));
-       free(btrn->name);
-       free(btrn);
-       return 1;
 }
 
 /**
@@ -307,9 +329,9 @@ void *btr_context(struct btr_node *btrn)
  *
  * This is a quite expensive operation.
  *
- * \return The number of buffers that have been merged (zero, one or two).
+ * \return The number of buffers that have been available (zero, one or two).
  */
-int btr_merge(struct btr_node *btrn)
+static int merge_input(struct btr_node *btrn)
 {
        struct btr_buffer_reference *brs[2], *br;
        char *bufs[2], *buf;
@@ -349,3 +371,59 @@ int btr_merge(struct btr_node *btrn)
        para_list_add(&br->node, &btrn->input_queue);
        return 2;
 }
+
+void btr_merge(struct btr_node *btrn, size_t dest_size)
+{
+       for (;;) {
+               char *buf;
+               size_t len = btr_next_buffer(btrn, &buf);
+               if (len >= dest_size)
+                       return;
+               if (merge_input(btrn) < 2)
+                       return;
+       }
+}
+
+bool btr_eof(struct btr_node *btrn)
+{
+       char *buf;
+       size_t len = btr_next_buffer(btrn, &buf);
+
+       return (len == 0 && btr_no_parent(btrn));
+}
+
+void log_tree_recursively(struct btr_node *btrn, int loglevel, int depth)
+{
+       struct btr_node *ch;
+       const char spaces[] = "                 ", *space = spaces + 16 - depth;
+
+       if (depth > 16)
+               return;
+       para_log(loglevel, "%s%s\n", space, btrn->name);
+       FOR_EACH_CHILD(ch, btrn)
+               log_tree_recursively(ch, loglevel, depth + 1);
+}
+
+void btr_log_tree(struct btr_node *btrn, int loglevel)
+{
+       return log_tree_recursively(btrn, loglevel, 0);
+}
+
+/** 640K ought to be enough for everybody ;) */
+#define BTRN_MAX_PENDING (640 * 1024)
+
+int btr_node_status(struct btr_node *btrn, size_t min_iqs)
+{
+       size_t iqs;
+
+       if (btr_eof(btrn))
+               return -E_BTR_EOF;
+       if (btr_bytes_pending(btrn) > BTRN_MAX_PENDING)
+               return 0;
+       iqs = btr_get_input_queue_size(btrn);
+       if (iqs == 0) /* we have a parent, because not eof */
+               return 0;
+       if (iqs < min_iqs && !btr_no_parent(btrn))
+               return 0;
+       return 1;
+}