| Index: src/platform/vboot_reference/cgptlib/quick_sort.c
|
| diff --git a/src/platform/vboot_reference/cgptlib/quick_sort.c b/src/platform/vboot_reference/cgptlib/quick_sort.c
|
| new file mode 100644
|
| index 0000000000000000000000000000000000000000..4af045de65004fd5caf95284b028b2be67d73588
|
| --- /dev/null
|
| +++ b/src/platform/vboot_reference/cgptlib/quick_sort.c
|
| @@ -0,0 +1,59 @@
|
| +/* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
|
| + * Use of this source code is governed by a BSD-style license that can be
|
| + * found in the LICENSE file.
|
| + */
|
| +#include "quick_sort.h"
|
| +#include <stdint.h>
|
| +#include "utility.h"
|
| +
|
| +/* Make sure we won't overflow the buffer. */
|
| +#define SAFE_SIZE(size) \
|
| + ((size > MAX_QUICK_SORT_ELEMENT_SIZE) ? MAX_QUICK_SORT_ELEMENT_SIZE : size)
|
| +
|
| +/* Swap a and b. Since the type of 'a' and 'b' are unknown, caller must indicate
|
| + * 'size' bytes. */
|
| +void Swap(void *a, void *b, int size) {
|
| + static uint8_t buffer[MAX_QUICK_SORT_ELEMENT_SIZE];
|
| + Memcpy(buffer, a, SAFE_SIZE(size));
|
| + Memcpy(a, b, SAFE_SIZE(size));
|
| + Memcpy(b, buffer, SAFE_SIZE(size));
|
| +}
|
| +
|
| +/* Given a pivot and left/right boundary, this function returns a new pivot,
|
| + * and ensure the elements in the left-side of pivot are preceding elements,
|
| + * and elements in the right-side of pivot are following elements. */
|
| +static int
|
| +Partition(int (*compare_function)(const void *a, const void *b),
|
| + void *vp_elements, int size, int left, int right, int pivot) {
|
| + uint8_t *elements = vp_elements;
|
| + int i;
|
| +
|
| + Swap(&elements[right * size], &elements[pivot * size], size);
|
| + for (i = left; i < right; ++i) {
|
| + if (compare_function(&elements[i * size], &elements[right * size])) {
|
| + Swap(&elements[left * size], &elements[i * size], size);
|
| + ++left;
|
| + }
|
| + }
|
| + Swap(&elements[left * size], &elements[right * size], size);
|
| + return left;
|
| +}
|
| +
|
| +/* Given left and right boundary, this function returns a sorted elements in
|
| + * that range. */
|
| +static void
|
| +RecursiveQuickSort(void *elements, int left, int right, int size,
|
| + int (*compare_function)(const void *a, const void *b)) {
|
| + int pivot;
|
| +
|
| + if (right <= left) return;
|
| + pivot = (left + right) / 2;
|
| + pivot = Partition(compare_function, elements, size, left, right, pivot);
|
| + RecursiveQuickSort(elements, left, pivot - 1, size, compare_function);
|
| + RecursiveQuickSort(elements, pivot + 1, right, size, compare_function);
|
| +}
|
| +
|
| +void QuickSort(void *elements, int number_of_elements, int size,
|
| + int (*compare_function)(const void *a, const void *b)) {
|
| + RecursiveQuickSort(elements, 0, number_of_elements - 1, size, compare_function);
|
| +}
|
|
|