mescc: Mes C Library: Fix qsort to support duplicate entries.

* lib/stdlib/qsort.c (qpart): Handle dupes.
* scaffold/tests/81-qsort-dupes.c: New file.
* build-aux/check-mescc.sh (tests): Run it.
This commit is contained in:
Jan Nieuwenhuizen 2018-08-27 22:37:12 +02:00
parent 06e9dd4bce
commit f22cc0c173
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GPG Key ID: F3C1A0D9C1D65273
3 changed files with 47 additions and 1 deletions

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@ -125,6 +125,7 @@ t
7s-struct-short
80-setjmp
81-qsort
81-qsort-dupes
82-define
83-heterogenoous-init
84-struct-field-list

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@ -37,11 +37,14 @@ qpart (void *base, size_t count, size_t size, int (*compare)(void const *, void
size_t i = 0;
for (size_t j = 0; j < count; j++)
{
if (compare (base+j*size, p) < 0)
int c = compare (base+j*size, p);
if (c < 0)
{
qswap (base+i*size, base+j*size, size);
i++;
}
else if (c == 0)
i++;
}
if (compare (base+count*size, base+i*size) < 0)
qswap (base+i*size, base+count*size, size);

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@ -0,0 +1,42 @@
/* -*-comment-start: "//";comment-end:""-*-
* GNU Mes --- Maxwell Equations of Software
* Copyright © 2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
*
* This file is part of GNU Mes.
*
* GNU Mes is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or (at
* your option) any later version.
*
* GNU Mes 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Mes. If not, see <http://www.gnu.org/licenses/>.
*/
#include <libmes.h>
#include <string.h>
int
qsort_strcmp (void const* a, void const* b)
{
return strcmp (*((char**) a), *((char**) b));
}
int
main ()
{
char* list[3] = {"foo", "foo", 0 };
oputs ("\nls:\n");
qsort (list, 2, sizeof (char*), qsort_strcmp);
for (int i = 0; i < 2; i++)
{
oputs (list[i]); oputs ("\n");
}
return 0;
}