platform_bionic/libc/bionic/tfind.c
Ben Cheng 21eab513e7 New additions/bug fixes required/found when porting perf.
New functions:
	tfind
	tsearch
	tdelete
	twalk
	tdestroy (GNU extension)

Bug fix: the current implementation for realpath would crash
	if the second argument (resolved_path) is NULL.

New headers:
	ar.h
	search.h

Change-Id: Ib6c1e42fc186a6d597a6e5a9692b16acaa155804
2012-03-20 12:54:55 -07:00

48 lines
1.2 KiB
C

/* $NetBSD: tfind.c,v 1.2 1999/09/16 11:45:37 lukem 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 0
#if defined(LIBC_SCCS) && !defined(lint)
__RCSID("$NetBSD: tfind.c,v 1.2 1999/09/16 11:45:37 lukem Exp $");
#endif /* LIBC_SCCS and not lint */
#endif
__FBSDID("$FreeBSD: release/9.0.0/lib/libc/stdlib/tfind.c 108694 2003-01-05 02:43:18Z tjr $");
#define _SEARCH_PRIVATE
#include <stdlib.h>
#include <search.h>
/* find a node, or return 0 */
void *
tfind(vkey, vrootp, compar)
const void *vkey; /* key to be found */
void * const *vrootp; /* address of the tree root */
int (*compar)(const void *, const void *);
{
node_t **rootp = (node_t **)vrootp;
if (rootp == NULL)
return NULL;
while (*rootp != NULL) { /* T1: */
int r;
if ((r = (*compar)(vkey, (*rootp)->key)) == 0) /* T2: */
return *rootp; /* key found */
rootp = (r < 0) ?
&(*rootp)->llink : /* T3: follow left branch */
&(*rootp)->rlink; /* T4: follow right branch */
}
return NULL;
}