From bfa2cee784125047771db2768fcf7f04d8bd6bb4 Mon Sep 17 00:00:00 2001 From: Tomas Vondra Date: Tue, 23 Mar 2021 00:11:20 +0100 Subject: [PATCH] Move bsearch_arg to src/port Until now the bsearch_arg function was used only in extended statistics code, so it was defined in that code. But we already have qsort_arg in src/port, so let's move it next to it. --- src/backend/statistics/extended_stats.c | 31 -------- src/include/port.h | 5 ++ .../statistics/extended_stats_internal.h | 5 -- src/port/Makefile | 1 + src/port/bsearch_arg.c | 78 +++++++++++++++++++ src/tools/msvc/Mkvcbuild.pm | 2 +- 6 files changed, 85 insertions(+), 37 deletions(-) create mode 100644 src/port/bsearch_arg.c diff --git a/src/backend/statistics/extended_stats.c b/src/backend/statistics/extended_stats.c index a030ea3653..fa42851fd5 100644 --- a/src/backend/statistics/extended_stats.c +++ b/src/backend/statistics/extended_stats.c @@ -659,37 +659,6 @@ compare_datums_simple(Datum a, Datum b, SortSupport ssup) return ApplySortComparator(a, false, b, false, ssup); } -/* simple counterpart to qsort_arg */ -void * -bsearch_arg(const void *key, const void *base, size_t nmemb, size_t size, - int (*compar) (const void *, const void *, void *), - void *arg) -{ - size_t l, - u, - idx; - const void *p; - int comparison; - - l = 0; - u = nmemb; - while (l < u) - { - idx = (l + u) / 2; - p = (void *) (((const char *) base) + (idx * size)); - comparison = (*compar) (key, p, arg); - - if (comparison < 0) - u = idx; - else if (comparison > 0) - l = idx + 1; - else - return (void *) p; - } - - return NULL; -} - /* * build_attnums_array * Transforms a bitmap into an array of AttrNumber values. diff --git a/src/include/port.h b/src/include/port.h index 227ef4b148..82f63de325 100644 --- a/src/include/port.h +++ b/src/include/port.h @@ -508,6 +508,11 @@ typedef int (*qsort_arg_comparator) (const void *a, const void *b, void *arg); extern void qsort_arg(void *base, size_t nel, size_t elsize, qsort_arg_comparator cmp, void *arg); +extern void *bsearch_arg(const void *key, const void *base, + size_t nmemb, size_t size, + int (*compar) (const void *, const void *, void *), + void *arg); + /* port/chklocale.c */ extern int pg_get_encoding_from_locale(const char *ctype, bool write_message); diff --git a/src/include/statistics/extended_stats_internal.h b/src/include/statistics/extended_stats_internal.h index c849bd57c0..a0a3cf5b0f 100644 --- a/src/include/statistics/extended_stats_internal.h +++ b/src/include/statistics/extended_stats_internal.h @@ -85,11 +85,6 @@ extern int multi_sort_compare_dims(int start, int end, const SortItem *a, extern int compare_scalars_simple(const void *a, const void *b, void *arg); extern int compare_datums_simple(Datum a, Datum b, SortSupport ssup); -extern void *bsearch_arg(const void *key, const void *base, - size_t nmemb, size_t size, - int (*compar) (const void *, const void *, void *), - void *arg); - extern AttrNumber *build_attnums_array(Bitmapset *attrs, int *numattrs); extern SortItem *build_sorted_items(int numrows, int *nitems, HeapTuple *rows, diff --git a/src/port/Makefile b/src/port/Makefile index e41b005c4f..52dbf5783f 100644 --- a/src/port/Makefile +++ b/src/port/Makefile @@ -40,6 +40,7 @@ LIBS += $(PTHREAD_LIBS) OBJS = \ $(LIBOBJS) \ $(PG_CRC32C_OBJS) \ + bsearch_arg.o \ chklocale.o \ erand48.o \ inet_net_ntop.o \ diff --git a/src/port/bsearch_arg.c b/src/port/bsearch_arg.c new file mode 100644 index 0000000000..0f1eaeba83 --- /dev/null +++ b/src/port/bsearch_arg.c @@ -0,0 +1,78 @@ +/* + * bsearch_arg.c: bsearch variant with a user-supplied pointer + * + * Copyright (c) 2021, PostgreSQL Global Development Group + * Copyright (c) 1990 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. [rescinded 22 July 1999] + * 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. + * + * src/port/bsearch_arg.c + */ + +#include "c.h" + +/* + * Perform a binary search. + * + * The code below is a bit sneaky. After a comparison fails, we + * divide the work in half by moving either left or right. If lim + * is odd, moving left simply involves halving lim: e.g., when lim + * is 5 we look at item 2, so we change lim to 2 so that we will + * look at items 0 & 1. If lim is even, the same applies. If lim + * is odd, moving right again involes halving lim, this time moving + * the base up one item past p: e.g., when lim is 5 we change base + * to item 3 and make lim 2 so that we will look at items 3 and 4. + * If lim is even, however, we have to shrink it by one before + * halving: e.g., when lim is 4, we still looked at item 2, so we + * have to make lim 3, then halve, obtaining 1, so that we will only + * look at item 3. + */ +void * +bsearch_arg(const void *key, const void *base0, + size_t nmemb, size_t size, + int (*compar) (const void *, const void *, void *), + void *arg) +{ + const char *base = (const char *) base0; + int lim, + cmp; + const void *p; + + for (lim = nmemb; lim != 0; lim >>= 1) + { + p = base + (lim >> 1) * size; + cmp = (*compar) (key, p, arg); + if (cmp == 0) + return (void *) p; + if (cmp > 0) + { /* key > p: move right */ + base = (const char *) p + size; + lim--; + } /* else move left */ + } + return (NULL); +} diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm index a184404e21..bc65185130 100644 --- a/src/tools/msvc/Mkvcbuild.pm +++ b/src/tools/msvc/Mkvcbuild.pm @@ -103,7 +103,7 @@ sub mkvcbuild dirent.c dlopen.c getopt.c getopt_long.c link.c pread.c preadv.c pwrite.c pwritev.c pg_bitutils.c pg_strong_random.c pgcheckdir.c pgmkdirp.c pgsleep.c pgstrcasecmp.c - pqsignal.c mkdtemp.c qsort.c qsort_arg.c quotes.c system.c + pqsignal.c mkdtemp.c qsort.c qsort_arg.c bsearch_arg.c quotes.c system.c strerror.c tar.c thread.c win32env.c win32error.c win32security.c win32setlocale.c win32stat.c);