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-rw-r--r--src/util/list_sort.c162
1 files changed, 0 insertions, 162 deletions
diff --git a/src/util/list_sort.c b/src/util/list_sort.c
deleted file mode 100644
index d4eeb9b36..000000000
--- a/src/util/list_sort.c
+++ /dev/null
@@ -1,162 +0,0 @@
-/*
- * Copyright (C) 2003-2014 The Music Player Daemon Project
- * http://www.musicpd.org
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
-/*
- * This code was imported from the Linux kernel.
- *
- */
-
-#include "list_sort.h"
-#include "list.h"
-#include "Macros.hxx"
-#include "Compiler.h"
-
-#include <string.h>
-
-#define unlikely gcc_unlikely
-
-#define MAX_LIST_LENGTH_BITS 20
-
-/*
- * Returns a list organized in an intermediate format suited
- * to chaining of merge() calls: null-terminated, no reserved or
- * sentinel head node, "prev" links not maintained.
- */
-static struct list_head *merge(void *priv,
- int (*cmp)(void *priv, struct list_head *a,
- struct list_head *b),
- struct list_head *a, struct list_head *b)
-{
- struct list_head head, *tail = &head;
-
- while (a && b) {
- /* if equal, take 'a' -- important for sort stability */
- if ((*cmp)(priv, a, b) <= 0) {
- tail->next = a;
- a = a->next;
- } else {
- tail->next = b;
- b = b->next;
- }
- tail = tail->next;
- }
- tail->next = a?a:b;
- return head.next;
-}
-
-/*
- * Combine final list merge with restoration of standard doubly-linked
- * list structure. This approach duplicates code from merge(), but
- * runs faster than the tidier alternatives of either a separate final
- * prev-link restoration pass, or maintaining the prev links
- * throughout.
- */
-static void merge_and_restore_back_links(void *priv,
- int (*cmp)(void *priv, struct list_head *a,
- struct list_head *b),
- struct list_head *head,
- struct list_head *a, struct list_head *b)
-{
- struct list_head *tail = head;
-
- while (a && b) {
- /* if equal, take 'a' -- important for sort stability */
- if ((*cmp)(priv, a, b) <= 0) {
- tail->next = a;
- a->prev = tail;
- a = a->next;
- } else {
- tail->next = b;
- b->prev = tail;
- b = b->next;
- }
- tail = tail->next;
- }
- tail->next = a ? a : b;
-
- do {
- /*
- * In worst cases this loop may run many iterations.
- * Continue callbacks to the client even though no
- * element comparison is needed, so the client's cmp()
- * routine can invoke cond_resched() periodically.
- */
- (*cmp)(priv, tail->next, tail->next);
-
- tail->next->prev = tail;
- tail = tail->next;
- } while (tail->next);
-
- tail->next = head;
- head->prev = tail;
-}
-
-/**
- * list_sort - sort a list
- * @priv: private data, opaque to list_sort(), passed to @cmp
- * @head: the list to sort
- * @cmp: the elements comparison function
- *
- * This function implements "merge sort", which has O(nlog(n))
- * complexity.
- *
- * The comparison function @cmp must return a negative value if @a
- * should sort before @b, and a positive value if @a should sort after
- * @b. If @a and @b are equivalent, and their original relative
- * ordering is to be preserved, @cmp must return 0.
- */
-void list_sort(void *priv, struct list_head *head,
- int (*cmp)(void *priv, struct list_head *a,
- struct list_head *b))
-{
- struct list_head *part[MAX_LIST_LENGTH_BITS+1]; /* sorted partial lists
- -- last slot is a sentinel */
- int lev; /* index into part[] */
- int max_lev = 0;
- struct list_head *list;
-
- if (list_empty(head))
- return;
-
- memset(part, 0, sizeof(part));
-
- head->prev->next = NULL;
- list = head->next;
-
- while (list) {
- struct list_head *cur = list;
- list = list->next;
- cur->next = NULL;
-
- for (lev = 0; part[lev]; lev++) {
- cur = merge(priv, cmp, part[lev], cur);
- part[lev] = NULL;
- }
- if (lev > max_lev) {
- max_lev = lev;
- }
- part[lev] = cur;
- }
-
- for (lev = 0; lev < max_lev; lev++)
- if (part[lev])
- list = merge(priv, cmp, part[lev], list);
-
- merge_and_restore_back_links(priv, cmp, head, part[max_lev], list);
-}