mirror of
https://gitlab.com/sortix/sortix.git
synced 2023-02-13 20:55:38 -05:00
62 lines
1.9 KiB
C++
62 lines
1.9 KiB
C++
/*******************************************************************************
|
|
|
|
Copyright(C) Jonas 'Sortie' Termansen 2012.
|
|
|
|
This file is part of the Sortix C Library.
|
|
|
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
|
it under the terms of the GNU Lesser General Public License as published by
|
|
the Free Software Foundation, either version 3 of the License, or (at your
|
|
option) any later version.
|
|
|
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
|
License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public License
|
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
sort.cpp
|
|
Utility functions related to sorting and sorted data.
|
|
|
|
*******************************************************************************/
|
|
|
|
#include <stdint.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
// TODO: This is an ugly hack!
|
|
static void memswap(uint8_t* a, uint8_t* b, size_t size)
|
|
{
|
|
uint8_t* tmp = (uint8_t*) malloc(size);
|
|
if ( !tmp ) { abort(); }
|
|
memcpy(tmp, a, size);
|
|
memcpy(a, b, size);
|
|
memcpy(b, tmp, size);
|
|
free(tmp);
|
|
}
|
|
|
|
// TODO: This is just a quick and dirty insertion sort. It'd be nice to have a
|
|
// good old quick sort here soon. Combined with the slow memswap above, this
|
|
// results in a very slow sorting algorithm.
|
|
extern "C" void qsort(void* base, size_t nmemb, size_t size,
|
|
int (* compare)(const void*, const void*))
|
|
{
|
|
uint8_t* buf = (uint8_t*) base;
|
|
for ( size_t i = 0; i < nmemb; i++ )
|
|
{
|
|
for ( size_t c = i; c; c-- )
|
|
{
|
|
size_t currentoff = c * size;
|
|
uint8_t* current = buf + currentoff;
|
|
size_t p = c-1;
|
|
size_t prevoff = p * size;
|
|
uint8_t* prev = buf + prevoff;
|
|
int cmp = compare(prev, current);
|
|
if ( cmp <= 0 ) { break; }
|
|
memswap(prev, current, size);
|
|
}
|
|
}
|
|
}
|
|
|