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Working hcreate(3) et al from NetBSD (cgd) via ray at cyth dot net.

Now passes the regress tests.
OPENBSD_3_6
millert 20 years ago
parent
commit
c90a644274
3 changed files with 401 additions and 5 deletions
  1. +6
    -5
      src/lib/libc/stdlib/Makefile.inc
  2. +195
    -0
      src/lib/libc/stdlib/hcreate.3
  3. +200
    -0
      src/lib/libc/stdlib/hcreate.c

+ 6
- 5
src/lib/libc/stdlib/Makefile.inc View File

@ -5,10 +5,10 @@
SRCS+= a64l.c abort.c atexit.c atoi.c atof.c atol.c atoll.c bsearch.c \
calloc.c cfree.c exit.c ecvt.c gcvt.c getenv.c getopt_long.c \
getsubopt.c heapsort.c l64a.c llabs.c lsearch.c malloc.c merge.c \
multibyte.c putenv.c qsort.c radixsort.c rand.c random.c realpath.c \
setenv.c strtod.c strtol.c strtoll.c strtonum.c strtoul.c strtoull.c \
system.c \
getsubopt.c hcreate.c heapsort.c l64a.c llabs.c lsearch.c malloc.c \
merge.c multibyte.c putenv.c qsort.c radixsort.c rand.c random.c \
realpath.c setenv.c strtod.c strtol.c strtoll.c strtonum.c strtoul.c \
strtoull.c system.c \
tfind.c tsearch.c _rand48.c drand48.c erand48.c jrand48.c lcong48.c \
lrand48.c mrand48.c nrand48.c seed48.c srand48.c qabs.c qdiv.c _Exit.c
@ -41,7 +41,7 @@ SRCS+= insque.c remque.c
MAN+= a64l.3 abort.3 abs.3 alloca.3 atexit.3 atof.3 atoi.3 atol.3 atoll.3 \
bsearch.3 div.3 ecvt.3 exit.3 getenv.3 getopt.3 getopt_long.3 \
getsubopt.3 insque.3 labs.3 ldiv.3 lsearch.3 malloc.3 qabs.3 \
getsubopt.3 hcreate.3 insque.3 labs.3 ldiv.3 lsearch.3 malloc.3 qabs.3 \
qdiv.3 qsort.3 radixsort.3 rand48.3 rand.3 random.3 realpath.3 \
strtod.3 strtonum.3 strtol.3 strtoul.3 system.3 tsearch.3
@ -49,6 +49,7 @@ MLINKS+=exit.3 _Exit.3
MLINKS+=ecvt.3 fcvt.3 ecvt.3 gcvt.3
MLINKS+=getenv.3 setenv.3 getenv.3 unsetenv.3 getenv.3 putenv.3
MLINKS+=getopt_long.3 getopt_long_only.3
MLINKS+=hcreate.3 hdestroy.3 hcreate.3 hsearch.3
MLINKS+=insque.3 remque.3
MLINKS+=labs.3 llabs.3
MLINKS+=lsearch.3 lfind.3


+ 195
- 0
src/lib/libc/stdlib/hcreate.3 View File

@ -0,0 +1,195 @@
.\" $OpenBSD: hcreate.3,v 1.1 2004/06/24 04:43:33 millert Exp $
.\" $NetBSD: hcreate.3,v 1.6 2003/04/16 13:34:46 wiz Exp $
.\"
.\" Copyright (c) 1999 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Klaus Klein.
.\"
.\" 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 NetBSD
.\" Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
.\"
.Dd February 13, 2001
.Dt HCREATE 3
.Os
.Sh NAME
.Nm hcreate ,
.Nm hdestroy ,
.Nm hsearch
.Nd manage hash search table
.Sh SYNOPSIS
.In search.h
.Ft int
.Fn hcreate "size_t nel"
.Ft void
.Fn hdestroy "void"
.Ft ENTRY *
.Fn hsearch "ENTRY item" "ACTION action"
.Sh DESCRIPTION
The
.Fn hcreate ,
.Fn hdestroy
and
.Fn hsearch
functions manage hash search tables.
.Pp
The
.Fn hcreate
function allocates and initializes the table.
The
.Fa nel
argument specifies an estimate of the maximum number of entries to be held
by the table.
Unless further memory allocation fails, supplying an insufficient
.Fa nel
value will not result in functional harm, although a performance degradation
may occur.
Initialization using the
.Fn hcreate
function is mandatory prior to any access operations using
.Fn hsearch .
.Pp
The
.Fn hdestroy
function destroys a table previously created using
.Fn hcreate .
After a call to
.Fn hdestroy ,
the data can no longer be accessed.
.Pp
The
.Fn hsearch
function is used to search to the hash table.
It returns a pointer into the
hash table indicating the address of an item.
The
.Fa item
argument is of type
.Dv ENTRY ,
a structural type which contains the following members:
.Bl -tag -compact -offset indent -width voidX*dataXX
.It Fa char *key
comparison key.
.It Fa void *data
pointer to data associated with
.Fa key .
.El
.Pp
The key comparison function used by
.Fn hsearch
is
.Xr strcmp 3 .
.Pp
The
.Fa action
argument is of type
.Dv ACTION ,
an enumeration type which defines the following values:
.Bl -tag -compact -offset indent -width ENTERXX
.It Dv ENTER
Insert
.Fa item
into the hash table.
If an existing item with the same key is found, it is not replaced.
Note that the
.Fa key
and
.Fa data
elements of
.Fa item
are used directly by the new table entry.
The storage for the
key must not be modified during the lifetime of the hash table.
.It Dv FIND
Search the hash table without inserting
.Fa item .
.El
.Sh RETURN VALUES
If successful, the
.Fn hcreate
function returns a non-zero value.
Otherwise, a value of 0 is returned and
.Va errno
is set to indicate the error.
.Pp
The
.Fn hdestroy
functions
returns no value.
.Pp
If successful, the
.Fn hsearch
function returns a pointer to hash table entry matching
the provided key.
If the action is
.Dv FIND
and the item was not found, or if the action is
.Dv ENTER
and the insertion failed,
.Dv NULL
is returned and
.Va errno
is set to indicate the error.
If the action is
.Dv ENTER
and an entry already existed in the table matching the given
key, the existing entry is returned and is not replaced.
.Sh ERRORS
The
.Fn hcreate
and
.Fn hsearch
functions will fail if:
.Bl -tag -width Er
.It Bq Er ENOMEM
Insufficient memory is available.
.El
.Sh SEE ALSO
.Xr bsearch 3 ,
.Xr lsearch 3 ,
.Xr malloc 3 ,
.Xr strcmp 3
.Sh STANDARDS
The
.Fn hcreate ,
.Fn hdestroy
and
.Fn hsearch
functions conform to
.St -xpg4.2 .
.Sh HISTORY
The
.Fn hcreate ,
.Fn hdestroy
and
.Fn hsearch
functions first appeared in
.At V .
.Sh BUGS
The interface permits the use of only one hash table at a time.

+ 200
- 0
src/lib/libc/stdlib/hcreate.c View File

@ -0,0 +1,200 @@
/* $OpenBSD: hcreate.c,v 1.1 2004/06/24 04:43:33 millert Exp $ */
/* $NetBSD: hcreate.c,v 1.5 2004/04/23 02:48:12 simonb Exp $ */
/*
* Copyright (c) 2001 Christopher G. Demetriou
* 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 for the
* NetBSD Project. See http://www.NetBSD.org/ for
* information about NetBSD.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
* <<Id: LICENSE,v 1.2 2000/06/14 15:57:33 cgd Exp>>
*/
/*
* hcreate() / hsearch() / hdestroy()
*
* SysV/XPG4 hash table functions.
*
* Implementation done based on NetBSD manual page and Solaris manual page,
* plus my own personal experience about how they're supposed to work.
*
* I tried to look at Knuth (as cited by the Solaris manual page), but
* nobody had a copy in the office, so...
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 2001 Christopher G. Demetriou. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
static const char rcsid[] = "$OpenBSD: hcreate.c,v 1.1 2004/06/24 04:43:33 millert Exp $";
#endif /* not lint */
#include "namespace.h"
#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <search.h>
#include <stdlib.h>
#include <string.h>
#include <sys/queue.h>
#ifndef _DIAGASSERT
#define _DIAGASSERT
#endif
/*
* DO NOT MAKE THIS STRUCTURE LARGER THAN 32 BYTES (4 ptrs on 64-bit
* ptr machine) without adjusting MAX_BUCKETS_LG2 below.
*/
struct internal_entry {
SLIST_ENTRY(internal_entry) link;
ENTRY ent;
};
SLIST_HEAD(internal_head, internal_entry);
#define MIN_BUCKETS_LG2 4
#define MIN_BUCKETS (1 << MIN_BUCKETS_LG2)
/*
* max * sizeof internal_entry must fit into size_t.
* assumes internal_entry is <= 32 (2^5) bytes.
*/
#define MAX_BUCKETS_LG2 (sizeof (size_t) * 8 - 1 - 5)
#define MAX_BUCKETS ((size_t)1 << MAX_BUCKETS_LG2)
/* Default hash function, from db/hash/hash_func.c */
extern u_int32_t (*__default_hash)(const void *, size_t);
static struct internal_head *htable;
static size_t htablesize;
int
hcreate(size_t nel)
{
size_t idx;
unsigned int p2;
/* Make sure this isn't called when a table already exists. */
_DIAGASSERT(htable == NULL);
if (htable != NULL) {
errno = EINVAL;
return 0;
}
/* If nel is too small, make it min sized. */
if (nel < MIN_BUCKETS)
nel = MIN_BUCKETS;
/* If it's too large, cap it. */
if (nel > MAX_BUCKETS)
nel = MAX_BUCKETS;
/* If it's is not a power of two in size, round up. */
if ((nel & (nel - 1)) != 0) {
for (p2 = 0; nel != 0; p2++)
nel >>= 1;
_DIAGASSERT(p2 <= MAX_BUCKETS_LG2);
nel = 1 << p2;
}
/* Allocate the table. */
htablesize = nel;
htable = malloc(htablesize * sizeof htable[0]);
if (htable == NULL) {
errno = ENOMEM;
return 0;
}
/* Initialize it. */
for (idx = 0; idx < htablesize; idx++)
SLIST_INIT(&htable[idx]);
return 1;
}
void
hdestroy(void)
{
struct internal_entry *ie;
size_t idx;
_DIAGASSERT(htable != NULL);
if (htable == NULL)
return;
for (idx = 0; idx < htablesize; idx++) {
while (!SLIST_EMPTY(&htable[idx])) {
ie = SLIST_FIRST(&htable[idx]);
SLIST_REMOVE_HEAD(&htable[idx], link);
free(ie->ent.key);
free(ie);
}
}
free(htable);
htable = NULL;
}
ENTRY *
hsearch(ENTRY item, ACTION action)
{
struct internal_head *head;
struct internal_entry *ie;
uint32_t hashval;
size_t len;
_DIAGASSERT(htable != NULL);
_DIAGASSERT(item.key != NULL);
_DIAGASSERT(action == ENTER || action == FIND);
len = strlen(item.key);
hashval = (*__default_hash)(item.key, len);
head = &htable[hashval & (htablesize - 1)];
ie = SLIST_FIRST(head);
while (ie != NULL) {
if (strcmp(ie->ent.key, item.key) == 0)
break;
ie = SLIST_NEXT(ie, link);
}
if (ie != NULL)
return &ie->ent;
else if (action == FIND)
return NULL;
ie = malloc(sizeof *ie);
if (ie == NULL)
return NULL;
ie->ent.key = item.key;
ie->ent.data = item.data;
SLIST_INSERT_HEAD(head, ie, link);
return &ie->ent;
}

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