/*
* Copyright (C) 2005 Sergey Bondari
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* @file sort.c
* @brief Sorting functions.
*
* This files contains functions implementing several sorting
* algorithms (e.g. quick sort and bubble sort).
*/
#include <mm/slab.h>
#include <memstr.h>
#include <sort.h>
#include <panic.h>
#define EBUFSIZE 32
void _qsort(void * data, count_t n, size_t e_size, int (* cmp) (void * a, void * b), void *tmp, void *pivot);
void _bubblesort(void * data, count_t n, size_t e_size, int (* cmp) (void * a, void * b), void *slot);
/** Quicksort wrapper
*
* This is only a wrapper that takes care of memory allocations for storing
* the pivot and temporary elements for generic quicksort algorithm.
*
* This function _can_ sleep
*
* @param data Pointer to data to be sorted.
* @param n Number of elements to be sorted.
* @param e_size Size of one element.
* @param cmp Comparator function.
*
*/
void qsort(void * data
, count_t n
, size_t e_size
, int (* cmp
) (void * a
, void * b
)) {
__u8 buf_tmp[EBUFSIZE];
__u8 buf_pivot[EBUFSIZE];
void * tmp = buf_tmp;
void * pivot = buf_pivot;
if (e_size > EBUFSIZE) {
pivot
= (void *) malloc(e_size
, 0); tmp
= (void *) malloc(e_size
, 0); }
_qsort(data, n, e_size, cmp, tmp, pivot);
if (e_size > EBUFSIZE) {
}
}
/** Quicksort
*
* Apply generic quicksort algorithm on supplied data, using pre-allocated buffers.
*
* @param data Pointer to data to be sorted.
* @param n Number of elements to be sorted.
* @param e_size Size of one element.
* @param cmp Comparator function.
* @param tmp Pointer to scratch memory buffer e_size bytes long.
* @param pivot Pointer to scratch memory buffer e_size bytes long.
*
*/
void _qsort(void * data, count_t n, size_t e_size, int (* cmp) (void * a, void * b), void *tmp, void *pivot)
{
if (n > 4) {
int i = 0, j = n - 1;
while (1) {
while ((cmp(data + i * e_size, pivot) < 0) && i < n) i++;
while ((cmp(data + j * e_size, pivot) >=0) && j > 0) j--;
if (i<j) {
memcpy(tmp
, data
+ i
* e_size
, e_size
); memcpy(data
+ i
* e_size
, data
+ j
* e_size
, e_size
); memcpy(data
+ j
* e_size
, tmp
, e_size
); } else {
break;
}
}
_qsort(data, j + 1, e_size, cmp, tmp, pivot);
_qsort(data + (j + 1) * e_size, n - j - 1, e_size, cmp, tmp, pivot);
} else {
_bubblesort(data, n, e_size, cmp, tmp);
}
}
/** Bubblesort wrapper
*
* This is only a wrapper that takes care of memory allocation for storing
* the slot element for generic bubblesort algorithm.
*
* @param data Pointer to data to be sorted.
* @param n Number of elements to be sorted.
* @param e_size Size of one element.
* @param cmp Comparator function.
*
*/
void bubblesort(void * data, count_t n, size_t e_size, int (* cmp) (void * a, void * b))
{
__u8 buf_slot[EBUFSIZE];
void * slot = buf_slot;
if (e_size > EBUFSIZE) {
slot
= (void *) malloc(e_size
, 0); }
_bubblesort(data, n, e_size, cmp, slot);
if (e_size > EBUFSIZE) {
}
}
/** Bubblesort
*
* Apply generic bubblesort algorithm on supplied data, using pre-allocated buffer.
*
* @param data Pointer to data to be sorted.
* @param n Number of elements to be sorted.
* @param e_size Size of one element.
* @param cmp Comparator function.
* @param slot Pointer to scratch memory buffer e_size bytes long.
*
*/
void _bubblesort(void * data, count_t n, size_t e_size, int (* cmp) (void * a, void * b), void *slot)
{
bool done = false;
void * p;
while (!done) {
done = true;
for (p = data; p < data + e_size * (n - 1); p = p + e_size) {
if (cmp(p, p + e_size) == 1) {
memcpy(p
, p
+ e_size
, e_size
); memcpy(p
+ e_size
, slot
, e_size
); done = false;
}
}
}
}
/*
* Comparator returns 1 if a > b, 0 if a == b, -1 if a < b
*/
int int_cmp(void * a, void * b)
{
return (* (int *) a > * (int*)b) ? 1 : (*(int *)a < * (int *)b) ? -1 : 0;
}
int __u8_cmp(void * a, void * b)
{
return (* (__u8 *) a > * (__u8 *)b) ? 1 : (*(__u8 *)a < * (__u8 *)b) ? -1 : 0;
}
int __u16_cmp(void * a, void * b)
{
return (* (__u16 *) a > * (__u16 *)b) ? 1 : (*(__u16 *)a < * (__u16 *)b) ? -1 : 0;
}
int __u32_cmp(void * a, void * b)
{
return (* (__u32 *) a > * (__u32 *)b) ? 1 : (*(__u32 *)a < * (__u32 *)b) ? -1 : 0;
}