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-rw-r--r--mergesort.c73
1 files changed, 0 insertions, 73 deletions
diff --git a/mergesort.c b/mergesort.c
deleted file mode 100644
index e5fdf2ee4a..0000000000
--- a/mergesort.c
+++ /dev/null
@@ -1,73 +0,0 @@
-#include "cache.h"
-#include "mergesort.h"
-
-struct mergesort_sublist {
- void *ptr;
- unsigned long len;
-};
-
-static void *get_nth_next(void *list, unsigned long n,
- void *(*get_next_fn)(const void *))
-{
- while (n-- && list)
- list = get_next_fn(list);
- return list;
-}
-
-static void *pop_item(struct mergesort_sublist *l,
- void *(*get_next_fn)(const void *))
-{
- void *p = l->ptr;
- l->ptr = get_next_fn(l->ptr);
- l->len = l->ptr ? (l->len - 1) : 0;
- return p;
-}
-
-void *llist_mergesort(void *list,
- void *(*get_next_fn)(const void *),
- void (*set_next_fn)(void *, void *),
- int (*compare_fn)(const void *, const void *))
-{
- unsigned long l;
-
- if (!list)
- return NULL;
- for (l = 1; ; l *= 2) {
- void *curr;
- struct mergesort_sublist p, q;
-
- p.ptr = list;
- q.ptr = get_nth_next(p.ptr, l, get_next_fn);
- if (!q.ptr)
- break;
- p.len = q.len = l;
-
- if (compare_fn(p.ptr, q.ptr) > 0)
- list = curr = pop_item(&q, get_next_fn);
- else
- list = curr = pop_item(&p, get_next_fn);
-
- while (p.ptr) {
- while (p.len || q.len) {
- void *prev = curr;
-
- if (!p.len)
- curr = pop_item(&q, get_next_fn);
- else if (!q.len)
- curr = pop_item(&p, get_next_fn);
- else if (compare_fn(p.ptr, q.ptr) > 0)
- curr = pop_item(&q, get_next_fn);
- else
- curr = pop_item(&p, get_next_fn);
- set_next_fn(prev, curr);
- }
- p.ptr = q.ptr;
- p.len = l;
- q.ptr = get_nth_next(p.ptr, l, get_next_fn);
- q.len = q.ptr ? l : 0;
-
- }
- set_next_fn(curr, NULL);
- }
- return list;
-}