#include "list.h"
#include "string.h"
#include "buffer_tree.h"
+#include "error.h"
struct btr_buffer {
* used by this btr node.
*/
struct list_head input_queue;
+ btr_command_handler execute;
+ void *context;
};
#define FOR_EACH_CHILD(_tn, _btrn) list_for_each_entry((_tn), \
&((_btrn)->children), node)
+#define FOR_EACH_CHILD_SAFE(_tn, _tmp, _btrn) \
+ list_for_each_entry_safe((_tn), (_tmp), &((_btrn)->children), node)
#define FOR_EACH_BUFFER_REF(_br, _btrn) \
list_for_each_entry((_br), &(_btrn)->input_queue, node)
#define FOR_EACH_BUFFER_REF_SAFE(_br, _tmp, _btrn) \
list_for_each_entry_safe((_br), (_tmp), &(_btrn)->input_queue, node)
-struct btr_node *btr_new_node(char *name, struct btr_node *parent)
+struct btr_node *btr_new_node(const char *name, struct btr_node *parent,
+ btr_command_handler handler, void *context)
{
struct btr_node *btrn = para_malloc(sizeof(*btrn));
btrn->name = para_strdup(name);
btrn->parent = parent;
+ btrn->execute = handler;
+ btrn->context = context;
if (parent)
list_add_tail(&btrn->node, &parent->children);
INIT_LIST_HEAD(&btrn->children);
INIT_LIST_HEAD(&btrn->input_queue);
+ if (parent)
+ PARA_INFO_LOG("added %s as child of %s\n", name, parent->name);
+ else
+ PARA_INFO_LOG("added %s as btr root\n", name);
return btrn;
}
{
struct btr_buffer *btrb = br->btrb;
+ //PARA_CRIT_LOG("dropping buffer reference %p\n", br);
list_del(&br->node);
free(br);
btrb->refcount--;
}
}
-static void add_btrb_to_children(struct btr_buffer *btrb, struct btr_node *btrn)
+static void add_btrb_to_children(struct btr_buffer *btrb,
+ struct btr_node *btrn, size_t consumed)
{
struct btr_node *ch;
FOR_EACH_CHILD(ch, btrn) {
struct btr_buffer_reference *br = para_malloc(sizeof(*br));
br->btrb = btrb;
- br->consumed = 0;
+ br->consumed = consumed;
list_add_tail(&br->node, &ch->input_queue);
btrb->refcount++;
}
{
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);
+ add_btrb_to_children(btrb, btrn, 0);
}
static void btr_pushdown_br(struct btr_buffer_reference *br, struct btr_node *btrn)
{
- add_btrb_to_children(br->btrb, btrn);
+ add_btrb_to_children(br->btrb, btrn, br->consumed);
btr_drop_buffer_reference(br);
}
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_is_leaf_node(struct btr_node *btrn)
+bool btr_no_children(struct btr_node *btrn)
{
return list_empty(&btrn->children);
}
return list_is_singular(&btrn->parent->children);
}
-struct btr_buffer_reference *btr_next_br(struct btr_node *btrn)
-{
- if (list_empty(&btrn->input_queue))
- return NULL;
- return list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
-}
-
-
static inline size_t br_available_bytes(struct btr_buffer_reference *br)
{
return br->btrb->size - br->consumed;
return br_available_bytes(br);
}
-void btr_increase_used_bytes(struct btr_buffer_reference *br, size_t consumed)
+/**
+ * \return zero if the input buffer queue is empty.
+ */
+size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
{
- br->consumed += consumed;
+ struct btr_buffer_reference *br;
+
+ if (list_empty(&btrn->input_queue)) {
+ *bufp = NULL;
+ return 0;
+ }
+ br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
+ return btr_get_buffer_by_reference(br, bufp);
+}
+
+void btr_consume(struct btr_node *btrn, size_t numbytes)
+{
+ struct btr_buffer_reference *br;
+
+ assert(!list_empty(&btrn->input_queue));
+ br = list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
+ assert(br->consumed + numbytes <= br->btrb->size);
+ br->consumed += numbytes;
if (br->consumed == br->btrb->size)
btr_drop_buffer_reference(br);
}
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("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)
struct btr_buffer_reference *br;
size_t size = 0;
- FOR_EACH_BUFFER_REF(br, btrn)
+ FOR_EACH_BUFFER_REF(br, btrn) {
+ //PARA_CRIT_LOG("size: %zu\n", size);
size += br_available_bytes(br);
+ }
return size;
}
+
+void btr_splice_out_node(struct btr_node *btrn)
+{
+ struct btr_node *ch, *tmp;
+
+ assert(btrn);
+ PARA_NOTICE_LOG("splicing out %s\n", btrn->name);
+ btr_pushdown(btrn);
+ if (btrn->parent)
+ list_del(&btrn->node);
+ FOR_EACH_CHILD_SAFE(ch, tmp, btrn) {
+ PARA_INFO_LOG("parent(%s): %s\n", ch->name,
+ btrn->parent? btrn->parent->name : "NULL");
+ ch->parent = btrn->parent;
+ if (btrn->parent)
+ list_move(&ch->node, &btrn->parent->children);
+ }
+ assert(list_empty(&btrn->children));
+}
+
+/**
+ * Return the size of the largest input queue.
+ *
+ * Iterates over all children of the given node.
+ */
+size_t btr_bytes_pending(struct btr_node *btrn)
+{
+ size_t max_size = 0;
+ struct btr_node *ch;
+
+ FOR_EACH_CHILD(ch, btrn) {
+ size_t size = btr_get_input_queue_size(ch);
+ max_size = PARA_MAX(max_size, size);
+ }
+ return max_size;
+}
+
+int btr_exec(struct btr_node *btrn, const char *command, char **value_result)
+{
+ if (!btrn)
+ return -ERRNO_TO_PARA_ERROR(EINVAL);
+ if (!btrn->execute)
+ return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+ return btrn->execute(btrn, command, value_result);
+}
+
+int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
+{
+ int ret;
+
+ for (; btrn; btrn = btrn->parent) {
+ struct btr_node *parent = btrn->parent;
+ if (!parent)
+ return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+ if (!parent->execute)
+ continue;
+ PARA_INFO_LOG("parent: %s, cmd: %s\n", parent->name, command);
+ ret = parent->execute(parent, command, value_result);
+ if (ret == -ERRNO_TO_PARA_ERROR(ENOTSUP))
+ continue;
+ if (ret < 0)
+ return ret;
+ if (value_result && *value_result)
+ PARA_NOTICE_LOG("%s(%s): %s\n", command, parent->name,
+ *value_result);
+ return 1;
+ }
+ return -ERRNO_TO_PARA_ERROR(ENOTSUP);
+}
+
+void *btr_context(struct btr_node *btrn)
+{
+ return btrn->context;
+}
+
+/**
+ * Merge the first two input buffers into one.
+ *
+ * This is a quite expensive operation.
+ *
+ * \return The number of buffers that have been available (zero, one or two).
+ */
+static int merge_input(struct btr_node *btrn)
+{
+ struct btr_buffer_reference *brs[2], *br;
+ char *bufs[2], *buf;
+ size_t szs[2], sz;
+ int i;
+
+ if (list_empty(&btrn->input_queue))
+ return 0;
+ if (list_is_singular(&btrn->input_queue))
+ return 1;
+ i = 0;
+ /* get references to the first two buffers */
+ FOR_EACH_BUFFER_REF(br, btrn) {
+ brs[i] = br;
+ szs[i] = btr_get_buffer_by_reference(brs[i], bufs + i);
+ i++;
+ if (i == 2)
+ break;
+ }
+ /* make a new btrb that combines the two buffers and a br to it. */
+ sz = szs[0] + szs[1];
+ //PARA_CRIT_LOG("merging input buffers: (%zu, %zu) -> %zu\n",
+ // szs[0], szs[1], sz);
+ buf = para_malloc(sz);
+ /* TODO: Avoid this memcopy by introducing btr buffer pool. */
+ memcpy(buf, bufs[0], szs[0]);
+ memcpy(buf + szs[0], bufs[1], szs[1]);
+
+ br = para_malloc(sizeof(*br));
+ br->btrb = new_btrb(buf, sz);
+ br->btrb->refcount = 1;
+ br->consumed = 0;
+
+ /* replace the first two refs by the new one */
+ btr_drop_buffer_reference(brs[0]);
+ btr_drop_buffer_reference(brs[1]);
+ 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;
+}
projects / paraslash.git / blobdiff