minix/lib/libc/stdlib/tsearch.c
Lionel Sambuc f14fb60209 Libraries updates and cleanup
* Updating common/lib
 * Updating lib/csu
 * Updating lib/libc
 * Updating libexec/ld.elf_so
 * Corrected test on __minix in featuretest to actually follow the
   meaning of the comment.
 * Cleaned up _REENTRANT-related defintions.
 * Disabled -D_REENTRANT for libfetch
 * Removing some unneeded __NBSD_LIBC defines and tests

Change-Id: Ic1394baef74d11b9f86b312f5ff4bbc3cbf72ce2
2013-01-14 11:36:26 +01:00

56 lines
1.4 KiB
C

/* $NetBSD: tsearch.c,v 1.7 2012/06/25 22:32:45 abs Exp $ */
/*
* Tree search generalized from Knuth (6.2.2) Algorithm T just like
* the AT&T man page says.
*
* The node_t structure is for internal use only, lint doesn't grok it.
*
* Written by reading the System V Interface Definition, not the code.
*
* Totally public domain.
*/
#include <sys/cdefs.h>
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: tsearch.c,v 1.7 2012/06/25 22:32:45 abs Exp $");
#endif /* LIBC_SCCS and not lint */
#include <assert.h>
#define _SEARCH_PRIVATE
#include <search.h>
#include <stdlib.h>
/* find or insert datum into search tree */
void *
tsearch(const void *vkey, void **vrootp,
int (*compar)(const void *, const void *))
{
node_t *q;
node_t **rootp = (node_t **)vrootp;
_DIAGASSERT(vkey != NULL);
_DIAGASSERT(compar != NULL);
if (rootp == NULL)
return NULL;
while (*rootp != NULL) { /* Knuth's T1: */
int r;
if ((r = (*compar)(vkey, (*rootp)->key)) == 0) /* T2: */
return *rootp; /* we found it! */
rootp = (r < 0) ?
&(*rootp)->llink : /* T3: follow left branch */
&(*rootp)->rlink; /* T4: follow right branch */
}
q = malloc(sizeof(node_t)); /* T5: key not found */
if (q != 0) { /* make new node */
*rootp = q; /* link new node to old */
q->key = __UNCONST(vkey); /* initialize new node */
q->llink = q->rlink = NULL;
}
return q;
}