b48252f365
descriptors against -1 (as appropriate).
* add actual checks which to detect stuff that would trigger_DIAGASSERT(),
and attempt to return a sane error condition.
* knf some code
* remove some `register' decls.
the first two items result in the addition of code similar to the
following in various functions:
_DIAGASSERT(path != NULL)
#ifdef _DIAGNOSTIC
if (path == NULL) {
errno = EFAULT;
return (-1);
}
#endif
54 lines
1.3 KiB
C
54 lines
1.3 KiB
C
/* $NetBSD: tfind.c,v 1.2 1999/09/16 11:45:37 lukem Exp $ */
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/*
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* Tree search generalized from Knuth (6.2.2) Algorithm T just like
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* the AT&T man page says.
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*
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* The node_t structure is for internal use only, lint doesn't grok it.
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*
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* Written by reading the System V Interface Definition, not the code.
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*
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* Totally public domain.
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*/
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#include <sys/cdefs.h>
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#if defined(LIBC_SCCS) && !defined(lint)
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__RCSID("$NetBSD: tfind.c,v 1.2 1999/09/16 11:45:37 lukem Exp $");
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#endif /* LIBC_SCCS and not lint */
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#include <assert.h>
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#define _SEARCH_PRIVATE
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#include <stdlib.h>
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#include <search.h>
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/* find a node, or return 0 */
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void *
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tfind(vkey, vrootp, compar)
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const void *vkey; /* key to be found */
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void **vrootp; /* address of the tree root */
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int (*compar) __P((const void *, const void *));
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{
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node_t **rootp = (node_t **)vrootp;
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_DIAGASSERT(vkey != NULL);
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_DIAGASSERT(compar != NULL);
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#ifdef _DIAGNOSTIC
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if (vkey == NULL || compar == NULL)
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return (NULL);
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#endif
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if (rootp == NULL)
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return NULL;
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while (*rootp != NULL) { /* T1: */
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int r;
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if ((r = (*compar)(vkey, (*rootp)->key)) == 0) /* T2: */
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return *rootp; /* key found */
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rootp = (r < 0) ?
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&(*rootp)->llink : /* T3: follow left branch */
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&(*rootp)->rlink; /* T4: follow right branch */
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}
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return NULL;
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}
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