-/*
- * Copyright (C) 2009-2013 Andre Noll <maan@systemlinux.org>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2009 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
/** \file buffer_tree.c Buffer tree and buffer pool implementations. */
#include <regex.h>
struct btr_pool *btrp;
PARA_INFO_LOG("%s, %zu bytes\n", name, area_size);
- btrp = para_malloc(sizeof(*btrp));
- btrp->area_start = para_malloc(area_size);
+ btrp = alloc(sizeof(*btrp));
+ btrp->area_start = alloc(area_size);
btrp->area_end = btrp->area_start + area_size;
btrp->rhead = btrp->area_start;
btrp->whead = btrp->area_start;
* \return The same value which was passed during creation time to
* btr_pool_new().
*/
-size_t btr_pool_size(struct btr_pool *btrp)
+size_t btr_pool_size(const struct btr_pool *btrp)
{
return btrp->area_end - btrp->area_start;
}
-static size_t btr_pool_filled(struct btr_pool *btrp)
+static size_t btr_pool_filled(const struct btr_pool *btrp)
{
if (!btrp->whead)
return btr_pool_size(btrp);
* the largest contiguous buffer that can currently be allocated from the
* buffer pool.
*/
-size_t btr_pool_unused(struct btr_pool *btrp)
+size_t btr_pool_unused(const struct btr_pool *btrp)
{
return btr_pool_size(btrp) - btr_pool_filled(btrp);
}
* Return maximal size available for one read. This is
* smaller than the value returned by btr_pool_unused().
*/
-static size_t btr_pool_available(struct btr_pool *btrp)
+static size_t btr_pool_available(const struct btr_pool *btrp)
{
if (!btrp->whead)
return 0;
* \return The maximal amount of bytes that may be written to the returned
* buffer.
*/
-size_t btr_pool_get_buffer(struct btr_pool *btrp, char **result)
+size_t btr_pool_get_buffer(const struct btr_pool *btrp, char **result)
{
if (result)
*result = btrp->whead;
* consists of two buffers. If this function returns the value n, then n
* elements of \a iov are initialized.
*/
-int btr_pool_get_buffers(struct btr_pool *btrp, struct iovec iov[2])
+int btr_pool_get_buffers(const struct btr_pool *btrp, struct iovec iov[2])
{
size_t sz, unused;
char *buf;
*/
struct btr_node *btr_new_node(struct btr_node_description *bnd)
{
- struct btr_node *btrn = para_malloc(sizeof(*btrn));
+ struct btr_node *btrn = alloc(sizeof(*btrn));
btrn->name = para_strdup(bnd->name);
btrn->parent = bnd->parent;
btrn->context = bnd->context;
btrn->start.tv_sec = 0;
btrn->start.tv_usec = 0;
- INIT_LIST_HEAD(&btrn->children);
- INIT_LIST_HEAD(&btrn->input_queue);
+ init_list_head(&btrn->children);
+ init_list_head(&btrn->input_queue);
if (!bnd->child) {
if (bnd->parent) {
list_add_tail(&btrn->node, &bnd->parent->children);
*/
static struct btr_buffer *new_btrb(char *buf, size_t size)
{
- struct btr_buffer *btrb = para_calloc(sizeof(*btrb));
+ struct btr_buffer *btrb = zalloc(sizeof(*btrb));
btrb->buf = buf;
btrb->size = size;
free(btrb->buf);
}
-static struct btr_buffer_reference *get_first_input_br(struct btr_node *btrn)
+static struct btr_buffer_reference *get_first_input_br(const struct btr_node *btrn)
{
if (list_empty(&btrn->input_queue))
return NULL;
struct btr_buffer_reference, node);
}
+static struct btr_buffer_reference *get_last_input_br(const struct btr_node *btrn)
+{
+ if (list_empty(&btrn->input_queue))
+ return NULL;
+ return list_last_entry(&btrn->input_queue,
+ struct btr_buffer_reference, node);
+}
+
/*
* Deallocate the reference, release the resources if refcount drops to zero.
*/
}
}
+static bool may_merge_btrb(const struct btr_buffer *btrb,
+ const struct btr_buffer_reference *br)
+{
+ if (!br)
+ return false;
+ if (br->consumed > 0)
+ return false;
+ if (br->btrb->buf + br->btrb->size != btrb->buf)
+ return false;
+ if (!br->btrb->pool)
+ return true;
+ return br->btrb->size + btrb->size < btr_pool_size(br->btrb->pool) / 3;
+}
+
static void add_btrb_to_children(struct btr_buffer *btrb,
struct btr_node *btrn, size_t consumed)
{
if (btrn->start.tv_sec == 0)
btrn->start = *now;
FOR_EACH_CHILD(ch, btrn) {
- struct btr_buffer_reference *br = para_calloc(sizeof(*br));
- br->btrb = btrb;
- br->consumed = consumed;
- list_add_tail(&br->node, &ch->input_queue);
- btrb->refcount++;
+ struct btr_buffer_reference *br = get_last_input_br(ch);
+ if (may_merge_btrb(btrb, br)) {
+ br->btrb->size += btrb->size;
+ free(btrb);
+ } else {
+ br = zalloc(sizeof(*br));
+ br->btrb = btrb;
+ br->consumed = consumed;
+ list_add_tail(&br->node, &ch->input_queue);
+ btrb->refcount++;
+ }
if (ch->start.tv_sec == 0)
ch->start = *now;
}
*
* \return True if this node has no children. False otherwise.
*/
-static bool btr_no_children(struct btr_node *btrn)
+static bool btr_no_children(const struct btr_node *btrn)
{
return list_empty(&btrn->children);
}
/**
- * 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)
+bool btr_no_parent(const struct btr_node *btrn)
{
return !btrn->parent;
}
* buffer.
*
* Since the buffer tree may change at any time, this function should be called
- * during each post_select call.
+ * during each post_monitor call.
*
* \return True if \a btrn has no siblings.
*/
-bool btr_inplace_ok(struct btr_node *btrn)
+bool btr_inplace_ok(const struct btr_node *btrn)
{
struct btr_buffer_reference *br;
FOR_EACH_BUFFER_REF(br, btrn) {
return true;
}
-static inline size_t br_available_bytes(struct btr_buffer_reference *br)
+static inline size_t br_available_bytes(const struct btr_buffer_reference *br)
{
return br->btrb->size - br->consumed;
}
-static size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char **buf)
+static size_t btr_get_buffer_by_reference(const struct btr_buffer_reference *br,
+ char **buf)
{
if (buf)
*buf = br->btrb->buf + br->consumed;
* to by \a btrn, the function returns zero and the value of \a bufp is
* undefined.
*/
-size_t btr_next_buffer_omit(struct btr_node *btrn, size_t omit, char **bufp)
+size_t btr_next_buffer_omit(const struct btr_node *btrn, size_t omit,
+ char **bufp)
{
struct btr_buffer_reference *br;
size_t wrap_count, sz, rv = 0;
* The call of this function is is equivalent to calling \ref
* btr_next_buffer_omit() with an \a omit value of zero.
*/
-size_t btr_next_buffer(struct btr_node *btrn, char **bufp)
+size_t btr_next_buffer(const struct btr_node *btrn, char **bufp)
{
return btr_next_buffer_omit(btrn, 0, bufp);
}
btr_drop_buffer_reference(br);
}
+static void btr_free_node(struct btr_node *btrn)
+{
+ free(btrn->name);
+ free(btrn);
+}
+
/**
* Remove a node from a buffer tree.
*
btr_drain(btrn);
if (btrn->parent)
list_del(&btrn->node);
- free(btrn->name);
- free(btrn);
+ btr_free_node(btrn);
out:
*btrnp = NULL;
}
* This simply iterates over all buffer references in the input queue and
* returns the sum of the sizes of all references.
*/
-size_t btr_get_input_queue_size(struct btr_node *btrn)
+size_t btr_get_input_queue_size(const struct btr_node *btrn)
{
struct btr_buffer_reference *br;
size_t size = 0, wrap_consumed = 0;
return size;
}
+static bool min_iqs_available(size_t min_iqs, const struct btr_node *btrn)
+{
+ struct btr_buffer_reference *br;
+ size_t have = 0, wrap_consumed = 0;
+
+ FOR_EACH_BUFFER_REF(br, btrn) {
+ if (br->wrap_count != 0) {
+ wrap_consumed = br->consumed;
+ continue;
+ }
+ have += br_available_bytes(br);
+ if (have > wrap_consumed + min_iqs)
+ return true;
+ }
+ return false;
+}
/**
* 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
* 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);
list_del(&ch->node);
}
assert(list_empty(&btrn->children));
- btrn->parent = NULL;
+ btr_free_node(btrn);
+ *btrnp = NULL;
}
/**
* \return This function iterates over all children of the given node and
* returns the size of the largest input queue.
*/
-size_t btr_get_output_queue_size(struct btr_node *btrn)
+size_t btr_get_output_queue_size(const struct btr_node *btrn)
{
size_t max_size = 0;
struct btr_node *ch;
* \return \p -ENOTSUP if no parent node of \a btrn understands \a command.
* Otherwise the return value of the command handler is returned.
*
- * \sa \ref receiver::execute, filter::execute, writer::execute.
+ * \sa \ref receiver::execute, \ref filter::execute, \ref writer::execute.
*/
-int btr_exec_up(struct btr_node *btrn, const char *command, char **value_result)
+int btr_exec_up(const struct btr_node *btrn, const char *command, char **value_result)
{
int ret;
*
* \return A pointer to the \a context address specified at node creation time.
*
- * \sa btr_new_node(), struct \ref btr_node_description.
+ * \sa \ref btr_new_node(), struct \ref btr_node_description.
*/
-void *btr_context(struct btr_node *btrn)
+void *btr_context(const struct btr_node *btrn)
{
return btrn->context;
}
-static bool need_buffer_pool_merge(struct btr_node *btrn)
+static bool need_buffer_pool_merge(const struct btr_node *btrn)
{
struct btr_buffer_reference *br = get_first_input_br(btrn);
if (!wbr) {
/* Make a new wrap buffer combining buf1 and buf2. */
sz = sz1 + sz2;
- buf = para_malloc(sz);
+ buf = alloc(sz);
PARA_DEBUG_LOG("merging input buffers: (%p:%zu, %p:%zu) -> %p:%zu\n",
buf1, sz1, buf2, sz2, buf, sz);
memcpy(buf, buf1, sz1);
memcpy(buf + sz1, buf2, sz2);
- br = para_calloc(sizeof(*br));
+ br = zalloc(sizeof(*br));
br->btrb = new_btrb(buf, sz);
br->btrb->refcount = 1;
br->consumed = 0;
assert(i == 2);
/* make a new btrb that combines the two buffers and a br to it. */
sz = szs[0] + szs[1];
- buf = para_malloc(sz);
+ buf = alloc(sz);
PARA_DEBUG_LOG("%s: memory merging input buffers: (%zu, %zu) -> %zu\n",
btrn->name, szs[0], szs[1], sz);
memcpy(buf, bufs[0], szs[0]);
memcpy(buf + szs[0], bufs[1], szs[1]);
- br = para_calloc(sizeof(*br));
+ br = zalloc(sizeof(*br));
br->btrb = new_btrb(buf, sz);
br->btrb->refcount = 1;
}
}
-static bool btr_eof(struct btr_node *btrn)
+static bool btr_eof(const struct btr_node *btrn)
{
char *buf;
size_t len = btr_next_buffer(btrn, &buf);
return (len == 0 && btr_no_parent(btrn));
}
-static void log_tree_recursively(struct btr_node *btrn, int loglevel, int depth)
+static void log_tree_recursively(const struct btr_node *btrn, int loglevel, int depth)
{
struct btr_node *ch;
const char spaces[] = " ", *space = spaces + 16 - depth;
* \param btrn Start logging at this node.
* \param loglevel Set severity with which the tree should be logged.
*/
-void btr_log_tree(struct btr_node *btrn, int loglevel)
+void btr_log_tree(const struct btr_node *btrn, int loglevel)
{
return log_tree_recursively(btrn, loglevel, 0);
}
* \param type The supposed type of \a btrn.
*
* Most users of the buffer tree subsystem call this function from both
- * their pre_select and the post_select methods.
+ * their ->pre_monitor() and ->post_monitor() methods.
*
* \return Negative if an error condition was detected, zero if there
* is nothing to do and positive otherwise.
* btrn, the function also returns zero in order to bound the memory usage of
* the buffer tree.
*/
-int btr_node_status(struct btr_node *btrn, size_t min_iqs,
+int btr_node_status(const struct btr_node *btrn, size_t min_iqs,
enum btr_node_type type)
{
- size_t iqs;
+ if (type != BTR_NT_LEAF && btr_no_children(btrn))
+ return -E_BTR_NO_CHILD;
+ if (type != BTR_NT_ROOT && btr_eof(btrn))
+ return -E_EOF;
- assert(btrn);
- if (type != BTR_NT_LEAF) {
- if (btr_no_children(btrn))
- return -E_BTR_NO_CHILD;
- if (btr_get_output_queue_size(btrn) > BTRN_MAX_PENDING)
- return 0;
- }
- if (type != BTR_NT_ROOT) {
- if (btr_eof(btrn))
- return -E_BTR_EOF;
- 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;
+ if (btr_get_output_queue_size(btrn) > BTRN_MAX_PENDING)
+ return 0;
+ if (type == BTR_NT_ROOT)
+ return 1;
+ if (min_iqs_available(min_iqs, btrn))
+ return 1;
+ return btr_no_parent(btrn);
}
/**
*
* Mainly useful for the time display of para_audiod.
*/
-void btr_get_node_start(struct btr_node *btrn, struct timeval *tv)
+void btr_get_node_start(const struct btr_node *btrn, struct timeval *tv)
{
*tv = btrn->start;
}
* \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)
+struct btr_node *btr_parent(const struct btr_node *btrn)
{
return btrn->parent;
}
projects / paraslash.git / blobdiff