--- /dev/null
+/*
+ * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ *
+ * The contents of this file constitute Original Code as defined in and
+ * are subject to the Apple Public Source License Version 1.1 (the
+ * "License"). You may not use this file except in compliance with the
+ * License. Please obtain a copy of the License at
+ * http://www.apple.com/publicsource and read it before using this file.
+ *
+ * This Original Code and all software distributed under the License are
+ * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
+ * License for the specific language governing rights and limitations
+ * under the License.
+ *
+ * @APPLE_LICENSE_HEADER_END@
+ */
+/*
+ * Copyright (c) 1992, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
+ */
+
+
+#include <sys/types.h>
+#include <stdlib.h>
+
+static inline char *med3 __P((char *, char *, char *, int (*)()));
+static inline void swapfunc __P((char *, char *, int, int));
+
+#define min(a, b) (a) < (b) ? a : b
+
+/*
+ * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
+ */
+#define swapcode(TYPE, parmi, parmj, n) { \
+ long i = (n) / sizeof (TYPE); \
+ register TYPE *pi = (TYPE *) (parmi); \
+ register TYPE *pj = (TYPE *) (parmj); \
+ do { \
+ register TYPE t = *pi; \
+ *pi++ = *pj; \
+ *pj++ = t; \
+ } while (--i > 0); \
+}
+
+#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
+ es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;
+
+static inline void
+swapfunc(a, b, n, swaptype)
+ char *a, *b;
+ int n, swaptype;
+{
+ if(swaptype <= 1)
+ swapcode(long, a, b, n)
+ else
+ swapcode(char, a, b, n)
+}
+
+#define swap(a, b) \
+ if (swaptype == 0) { \
+ long t = *(long *)(a); \
+ *(long *)(a) = *(long *)(b); \
+ *(long *)(b) = t; \
+ } else \
+ swapfunc(a, b, es, swaptype)
+
+#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
+
+static inline char *
+med3(a, b, c, cmp)
+ char *a, *b, *c;
+ int (*cmp)();
+{
+ return cmp(a, b) < 0 ?
+ (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a ))
+ :(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c ));
+}
+
+void
+qsort(a, n, es, cmp)
+ void *a;
+ size_t n, es;
+ int (*cmp)();
+{
+ char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+ int d, r, swaptype, swap_cnt;
+
+loop: SWAPINIT(a, es);
+ swap_cnt = 0;
+ if (n < 7) {
+ for (pm = a + es; pm < (char *) a + n * es; pm += es)
+ for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
+ pl -= es)
+ swap(pl, pl - es);
+ return;
+ }
+ pm = a + (n / 2) * es;
+ if (n > 7) {
+ pl = a;
+ pn = a + (n - 1) * es;
+ if (n > 40) {
+ d = (n / 8) * es;
+ pl = med3(pl, pl + d, pl + 2 * d, cmp);
+ pm = med3(pm - d, pm, pm + d, cmp);
+ pn = med3(pn - 2 * d, pn - d, pn, cmp);
+ }
+ pm = med3(pl, pm, pn, cmp);
+ }
+ swap(a, pm);
+ pa = pb = a + es;
+
+ pc = pd = a + (n - 1) * es;
+ for (;;) {
+ while (pb <= pc && (r = cmp(pb, a)) <= 0) {
+ if (r == 0) {
+ swap_cnt = 1;
+ swap(pa, pb);
+ pa += es;
+ }
+ pb += es;
+ }
+ while (pb <= pc && (r = cmp(pc, a)) >= 0) {
+ if (r == 0) {
+ swap_cnt = 1;
+ swap(pc, pd);
+ pd -= es;
+ }
+ pc -= es;
+ }
+ if (pb > pc)
+ break;
+ swap(pb, pc);
+ swap_cnt = 1;
+ pb += es;
+ pc -= es;
+ }
+ if (swap_cnt == 0) { /* Switch to insertion sort */
+ for (pm = a + es; pm < (char *) a + n * es; pm += es)
+ for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
+ pl -= es)
+ swap(pl, pl - es);
+ return;
+ }
+
+ pn = a + n * es;
+ r = min(pa - (char *)a, pb - pa);
+ vecswap(a, pb - r, r);
+ r = min(pd - pc, pn - pd - es);
+ vecswap(pb, pn - r, r);
+ if ((r = pb - pa) > es)
+ qsort(a, r / es, es, cmp);
+ if ((r = pd - pc) > es) {
+ /* Iterate rather than recurse to save stack space */
+ a = pn - r;
+ n = r / es;
+ goto loop;
+ }
+/* qsort(pn - r, r / es, es, cmp);*/
+}
projects / apple / libc.git / blobdiff