php-src/Zend/zend_qsort.c
2014-01-03 11:08:10 +08:00

134 lines
3.5 KiB
C

/*
+----------------------------------------------------------------------+
| Zend Engine |
+----------------------------------------------------------------------+
| Copyright (c) 1998-2014 Zend Technologies Ltd. (http://www.zend.com) |
+----------------------------------------------------------------------+
| This source file is subject to version 2.00 of the Zend license, |
| that is bundled with this package in the file LICENSE, and is |
| available through the world-wide-web at the following url: |
| http://www.zend.com/license/2_00.txt. |
| If you did not receive a copy of the Zend license and are unable to |
| obtain it through the world-wide-web, please send a note to |
| license@zend.com so we can mail you a copy immediately. |
+----------------------------------------------------------------------+
| Authors: Sterling Hughes <sterling@php.net> |
+----------------------------------------------------------------------+
*/
/* $Id$ */
#include "zend.h"
#include "zend_qsort.h"
#include <limits.h>
#define QSORT_STACK_SIZE (sizeof(size_t) * CHAR_BIT)
static void _zend_qsort_swap(void *a, void *b, size_t siz)
{
register char *tmp_a_char;
register char *tmp_b_char;
register int *tmp_a_int;
register int *tmp_b_int;
register size_t i;
int t_i;
char t_c;
tmp_a_int = (int *) a;
tmp_b_int = (int *) b;
for (i = sizeof(int); i <= siz; i += sizeof(int)) {
t_i = *tmp_a_int;
*tmp_a_int++ = *tmp_b_int;
*tmp_b_int++ = t_i;
}
tmp_a_char = (char *) tmp_a_int;
tmp_b_char = (char *) tmp_b_int;
for (i = i - sizeof(int) + 1; i <= siz; ++i) {
t_c = *tmp_a_char;
*tmp_a_char++ = *tmp_b_char;
*tmp_b_char++ = t_c;
}
}
ZEND_API void zend_qsort_r(void *base, size_t nmemb, size_t siz, compare_r_func_t compare, void *arg TSRMLS_DC)
{
void *begin_stack[QSORT_STACK_SIZE];
void *end_stack[QSORT_STACK_SIZE];
register char *begin;
register char *end;
register char *seg1;
register char *seg2;
register char *seg2p;
register int loop;
uint offset;
begin_stack[0] = (char *) base;
end_stack[0] = (char *) base + ((nmemb - 1) * siz);
for (loop = 0; loop >= 0; --loop) {
begin = begin_stack[loop];
end = end_stack[loop];
while (begin < end) {
offset = (end - begin) >> 1;
_zend_qsort_swap(begin, begin + (offset - (offset % siz)), siz);
seg1 = begin + siz;
seg2 = end;
while (1) {
for (; seg1 < seg2 && compare(begin, seg1 TSRMLS_CC, arg) > 0;
seg1 += siz);
for (; seg2 >= seg1 && compare(seg2, begin TSRMLS_CC, arg) > 0;
seg2 -= siz);
if (seg1 >= seg2)
break;
_zend_qsort_swap(seg1, seg2, siz);
seg1 += siz;
seg2 -= siz;
}
_zend_qsort_swap(begin, seg2, siz);
seg2p = seg2;
if ((seg2p - begin) <= (end - seg2p)) {
if ((seg2p + siz) < end) {
begin_stack[loop] = seg2p + siz;
end_stack[loop++] = end;
}
end = seg2p - siz;
}
else {
if ((seg2p - siz) > begin) {
begin_stack[loop] = begin;
end_stack[loop++] = seg2p - siz;
}
begin = seg2p + siz;
}
}
}
}
ZEND_API void zend_qsort(void *base, size_t nmemb, size_t siz, compare_func_t compare TSRMLS_DC)
{
zend_qsort_r(base, nmemb, siz, (compare_r_func_t)compare, NULL TSRMLS_CC);
}
/*
* Local Variables:
* c-basic-offset: 4
* tab-width: 4
* End:
* vim600: fdm=marker
* vim: noet sw=4 ts=4
*/