[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Minios-devel] [UNIKRAFT PATCH v2 1/2] lib/nolib: Add qsort



From: Vlad-Andrei BĂDOIU <vlad_andrei.badoiu@xxxxxxxxxxxxxxx>

This qsort implementation is an adapted version of android bionic's
qsort. It is the Qsort routine from Bentley & McIlroy's "Engineering
a Sort Function".

Signed-off-by: Vlad-Andrei Badoiu <vlad_andrei.badoiu@xxxxxx>
---
 lib/nolibc/Makefile.uk      |   3 +
 lib/nolibc/exportsyms.uk    |   1 +
 lib/nolibc/include/stdlib.h |   3 +
 lib/nolibc/qsort.c          | 157 ++++++++++++++++++++++++++++++++++++
 4 files changed, 164 insertions(+)
 create mode 100644 lib/nolibc/qsort.c

diff --git a/lib/nolibc/Makefile.uk b/lib/nolibc/Makefile.uk
index 7cb2e7d1..9d4a9ec3 100644
--- a/lib/nolibc/Makefile.uk
+++ b/lib/nolibc/Makefile.uk
@@ -35,5 +35,8 @@ LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/sscanf.c
 LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/asprintf.c
 LIBNOLIBC_SRCS-$(CONFIG_LIBUKALLOC) += $(LIBNOLIBC_BASE)/malloc.c
 
+
+LIBNOLIBC_SRCS-y += $(LIBNOLIBC_BASE)/qsort.c
+
 # Localize internal symbols (starting with __*)
 LIBNOLIBC_OBJCFLAGS-y += -w -L __*
diff --git a/lib/nolibc/exportsyms.uk b/lib/nolibc/exportsyms.uk
index f2d50f1f..f283d458 100644
--- a/lib/nolibc/exportsyms.uk
+++ b/lib/nolibc/exportsyms.uk
@@ -45,6 +45,7 @@ strtoul
 strtoll
 strtoull
 atoi
+qsort
 
 # string
 memcpy
diff --git a/lib/nolibc/include/stdlib.h b/lib/nolibc/include/stdlib.h
index cd6651c4..522da824 100644
--- a/lib/nolibc/include/stdlib.h
+++ b/lib/nolibc/include/stdlib.h
@@ -89,6 +89,9 @@ void *memalign(size_t align, size_t size);
 
 void abort(void) __noreturn;
 
+void qsort(void *base, size_t nmemb, size_t size,
+           int (*compar)(const void *, const void *));
+
 #if CONFIG_LIBPOSIX_PROCESS
 int system(const char *command);
 #endif
diff --git a/lib/nolibc/qsort.c b/lib/nolibc/qsort.c
new file mode 100644
index 00000000..d8b3ddc5
--- /dev/null
+++ b/lib/nolibc/qsort.c
@@ -0,0 +1,157 @@
+/*     $OpenBSD: qsort.c,v 1.10 2005/08/08 08:05:37 espie Exp $ */
+/*-
+ * 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. 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(char *, char *, char *, int (*)
+                               (const void *, const void *));
+static inline void      swapfunc(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);                    \
+       TYPE *pi = (TYPE *) (parmi);                    \
+       TYPE *pj = (TYPE *) (parmj);                    \
+       do {                                            \
+               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(char *a, char *b, int n, int swaptype)
+{
+       if (swaptype <= 1)
+               swapcode(long, a, b, n)
+       else
+               swapcode(char, a, b, n)
+}
+#define swap(a, b)                                     \
+       do {                                            \
+               if (swaptype == 0) {                            \
+                       long t = *(long *)(a);                  \
+                       *(long *)(a) = *(long *)(b);            \
+                       *(long *)(b) = t;                       \
+               } else                                          \
+                       swapfunc(a, b, es, swaptype);           \
+       } while (0)
+
+#define vecswap(a, b, n)                                       \
+       do {                                                    \
+               if ((n) > 0)                                    \
+                       swapfunc(a, b, n, swaptype);            \
+       } while (0)
+static inline char *
+med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
+{
+       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(void *aa, size_t n, size_t es, int (*cmp)(const void *, const void *))
+{
+       char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+       int d, r, swaptype, swap_cnt;
+       char *a = aa;
+loop:
+       SWAPINIT(a, es);
+       swap_cnt = 0;
+       if (n < 7) {
+               for (pm = (char *)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 = (char *)a + (n / 2) * es;
+       if (n > 7) {
+               pl = (char *)a;
+               pn = (char *)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 = (char *)a + es;
+
+       pc = pd = (char *)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 = (char *) 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 = (char *)a + n * es;
+       r = min(pa - (char *)a, pb - pa);
+       vecswap(a, pb - r, r);
+       r = min(pd - pc, pn - pd - (int)es);
+       vecswap(pb, pn - r, r);
+       if ((r = pb - pa) > (int)es)
+               qsort(a, r / es, es, cmp);
+       if ((r = pd - pc) > (int)es) {
+               /* Iterate rather than recurse to save stack space */
+               a = pn - r;
+               n = r / es;
+               goto loop;
+       }
+}
-- 
2.20.1


_______________________________________________
Minios-devel mailing list
Minios-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/minios-devel

 


Rackspace

Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.