It is a non-standard heap-sort algorithm implementation because the
index of child node is wrong . The sort function still outputs right
result, but the performance is O( n * ( log(n) + 1 ) ) , about 10% ~
20% worse than standard algorithm .
Signed-off-by: keios <[email protected]>
-----
diff -Nraup a/lib/sort.c b/lib/sort.c
--- a/lib/sort.c 2006-09-20 11:42:06.000000000 +0800
+++ b/lib/sort.c 2006-09-27 21:26:38.000000000 +0800
@@ -49,15 +49,15 @@ void sort(void *base, size_t num, size_t
void (*swap)(void *, void *, int size))
{
/* pre-scale counters for performance */
- int i = (num/2) * size, n = num * size, c, r;
+ int i = (num/2 - 1) * size, n = num * size, c, r;
if (!swap)
swap = (size == 4 ? u32_swap : generic_swap);
/* heapify */
for ( ; i >= 0; i -= size) {
- for (r = i; r * 2 < n; r = c) {
- c = r * 2;
+ for (r = i; r * 2 + size < n; r = c) {
+ c = r * 2 + size;
if (c < n - size && cmp(base + c, base + c + size) < 0)
c += size;
if (cmp(base + r, base + c) >= 0)
@@ -69,8 +69,8 @@ void sort(void *base, size_t num, size_t
/* sort */
for (i = n - size; i >= 0; i -= size) {
swap(base, base + i, size);
- for (r = 0; r * 2 < i; r = c) {
- c = r * 2;
+ for (r = 0; r * 2 + size < i; r = c) {
+ c = r * 2 + size;
if (c < i - size && cmp(base + c, base + c + size) < 0)
c += size;
if (cmp(base + r, base + c) >= 0)
-
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