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-rw-r--r--REORG.TODO/stdlib/msort.c310
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diff --git a/REORG.TODO/stdlib/msort.c b/REORG.TODO/stdlib/msort.c
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+/* An alternative to qsort, with an identical interface.
+ This file is part of the GNU C Library.
+ Copyright (C) 1992-2017 Free Software Foundation, Inc.
+ Written by Mike Haertel, September 1988.
+
+ The GNU 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 2.1 of the License, or (at your option) any later version.
+
+ The GNU 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 GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#include <alloca.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <memcopy.h>
+#include <errno.h>
+#include <atomic.h>
+
+struct msort_param
+{
+ size_t s;
+ size_t var;
+ __compar_d_fn_t cmp;
+ void *arg;
+ char *t;
+};
+static void msort_with_tmp (const struct msort_param *p, void *b, size_t n);
+
+static void
+msort_with_tmp (const struct msort_param *p, void *b, size_t n)
+{
+ char *b1, *b2;
+ size_t n1, n2;
+
+ if (n <= 1)
+ return;
+
+ n1 = n / 2;
+ n2 = n - n1;
+ b1 = b;
+ b2 = (char *) b + (n1 * p->s);
+
+ msort_with_tmp (p, b1, n1);
+ msort_with_tmp (p, b2, n2);
+
+ char *tmp = p->t;
+ const size_t s = p->s;
+ __compar_d_fn_t cmp = p->cmp;
+ void *arg = p->arg;
+ switch (p->var)
+ {
+ case 0:
+ while (n1 > 0 && n2 > 0)
+ {
+ if ((*cmp) (b1, b2, arg) <= 0)
+ {
+ *(uint32_t *) tmp = *(uint32_t *) b1;
+ b1 += sizeof (uint32_t);
+ --n1;
+ }
+ else
+ {
+ *(uint32_t *) tmp = *(uint32_t *) b2;
+ b2 += sizeof (uint32_t);
+ --n2;
+ }
+ tmp += sizeof (uint32_t);
+ }
+ break;
+ case 1:
+ while (n1 > 0 && n2 > 0)
+ {
+ if ((*cmp) (b1, b2, arg) <= 0)
+ {
+ *(uint64_t *) tmp = *(uint64_t *) b1;
+ b1 += sizeof (uint64_t);
+ --n1;
+ }
+ else
+ {
+ *(uint64_t *) tmp = *(uint64_t *) b2;
+ b2 += sizeof (uint64_t);
+ --n2;
+ }
+ tmp += sizeof (uint64_t);
+ }
+ break;
+ case 2:
+ while (n1 > 0 && n2 > 0)
+ {
+ unsigned long *tmpl = (unsigned long *) tmp;
+ unsigned long *bl;
+
+ tmp += s;
+ if ((*cmp) (b1, b2, arg) <= 0)
+ {
+ bl = (unsigned long *) b1;
+ b1 += s;
+ --n1;
+ }
+ else
+ {
+ bl = (unsigned long *) b2;
+ b2 += s;
+ --n2;
+ }
+ while (tmpl < (unsigned long *) tmp)
+ *tmpl++ = *bl++;
+ }
+ break;
+ case 3:
+ while (n1 > 0 && n2 > 0)
+ {
+ if ((*cmp) (*(const void **) b1, *(const void **) b2, arg) <= 0)
+ {
+ *(void **) tmp = *(void **) b1;
+ b1 += sizeof (void *);
+ --n1;
+ }
+ else
+ {
+ *(void **) tmp = *(void **) b2;
+ b2 += sizeof (void *);
+ --n2;
+ }
+ tmp += sizeof (void *);
+ }
+ break;
+ default:
+ while (n1 > 0 && n2 > 0)
+ {
+ if ((*cmp) (b1, b2, arg) <= 0)
+ {
+ tmp = (char *) __mempcpy (tmp, b1, s);
+ b1 += s;
+ --n1;
+ }
+ else
+ {
+ tmp = (char *) __mempcpy (tmp, b2, s);
+ b2 += s;
+ --n2;
+ }
+ }
+ break;
+ }
+
+ if (n1 > 0)
+ memcpy (tmp, b1, n1 * s);
+ memcpy (b, p->t, (n - n2) * s);
+}
+
+
+void
+__qsort_r (void *b, size_t n, size_t s, __compar_d_fn_t cmp, void *arg)
+{
+ size_t size = n * s;
+ char *tmp = NULL;
+ struct msort_param p;
+
+ /* For large object sizes use indirect sorting. */
+ if (s > 32)
+ size = 2 * n * sizeof (void *) + s;
+
+ if (size < 1024)
+ /* The temporary array is small, so put it on the stack. */
+ p.t = __alloca (size);
+ else
+ {
+ /* We should avoid allocating too much memory since this might
+ have to be backed up by swap space. */
+ static long int phys_pages;
+ static int pagesize;
+
+ if (pagesize == 0)
+ {
+ phys_pages = __sysconf (_SC_PHYS_PAGES);
+
+ if (phys_pages == -1)
+ /* Error while determining the memory size. So let's
+ assume there is enough memory. Otherwise the
+ implementer should provide a complete implementation of
+ the `sysconf' function. */
+ phys_pages = (long int) (~0ul >> 1);
+
+ /* The following determines that we will never use more than
+ a quarter of the physical memory. */
+ phys_pages /= 4;
+
+ /* Make sure phys_pages is written to memory. */
+ atomic_write_barrier ();
+
+ pagesize = __sysconf (_SC_PAGESIZE);
+ }
+
+ /* Just a comment here. We cannot compute
+ phys_pages * pagesize
+ and compare the needed amount of memory against this value.
+ The problem is that some systems might have more physical
+ memory then can be represented with a `size_t' value (when
+ measured in bytes. */
+
+ /* If the memory requirements are too high don't allocate memory. */
+ if (size / pagesize > (size_t) phys_pages)
+ {
+ _quicksort (b, n, s, cmp, arg);
+ return;
+ }
+
+ /* It's somewhat large, so malloc it. */
+ int save = errno;
+ tmp = malloc (size);
+ __set_errno (save);
+ if (tmp == NULL)
+ {
+ /* Couldn't get space, so use the slower algorithm
+ that doesn't need a temporary array. */
+ _quicksort (b, n, s, cmp, arg);
+ return;
+ }
+ p.t = tmp;
+ }
+
+ p.s = s;
+ p.var = 4;
+ p.cmp = cmp;
+ p.arg = arg;
+
+ if (s > 32)
+ {
+ /* Indirect sorting. */
+ char *ip = (char *) b;
+ void **tp = (void **) (p.t + n * sizeof (void *));
+ void **t = tp;
+ void *tmp_storage = (void *) (tp + n);
+
+ while ((void *) t < tmp_storage)
+ {
+ *t++ = ip;
+ ip += s;
+ }
+ p.s = sizeof (void *);
+ p.var = 3;
+ msort_with_tmp (&p, p.t + n * sizeof (void *), n);
+
+ /* tp[0] .. tp[n - 1] is now sorted, copy around entries of
+ the original array. Knuth vol. 3 (2nd ed.) exercise 5.2-10. */
+ char *kp;
+ size_t i;
+ for (i = 0, ip = (char *) b; i < n; i++, ip += s)
+ if ((kp = tp[i]) != ip)
+ {
+ size_t j = i;
+ char *jp = ip;
+ memcpy (tmp_storage, ip, s);
+
+ do
+ {
+ size_t k = (kp - (char *) b) / s;
+ tp[j] = jp;
+ memcpy (jp, kp, s);
+ j = k;
+ jp = kp;
+ kp = tp[k];
+ }
+ while (kp != ip);
+
+ tp[j] = jp;
+ memcpy (jp, tmp_storage, s);
+ }
+ }
+ else
+ {
+ if ((s & (sizeof (uint32_t) - 1)) == 0
+ && ((char *) b - (char *) 0) % __alignof__ (uint32_t) == 0)
+ {
+ if (s == sizeof (uint32_t))
+ p.var = 0;
+ else if (s == sizeof (uint64_t)
+ && ((char *) b - (char *) 0) % __alignof__ (uint64_t) == 0)
+ p.var = 1;
+ else if ((s & (sizeof (unsigned long) - 1)) == 0
+ && ((char *) b - (char *) 0)
+ % __alignof__ (unsigned long) == 0)
+ p.var = 2;
+ }
+ msort_with_tmp (&p, b, n);
+ }
+ free (tmp);
+}
+libc_hidden_def (__qsort_r)
+weak_alias (__qsort_r, qsort_r)
+
+
+void
+qsort (void *b, size_t n, size_t s, __compar_fn_t cmp)
+{
+ return __qsort_r (b, n, s, (__compar_d_fn_t) cmp, NULL);
+}
+libc_hidden_def (qsort)
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