[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
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