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mirror of git://sourceware.org/git/newlib-cygwin.git synced 2025-01-15 11:00:04 +08:00
Jeff Johnston 729d1ff9d8 2003-06-06 Jeff Johnston <jjohnstn@redhat.com>
* libc/argz/argz_add.c: Change to use _DEFUN macro for function
        definition.
        * libc/argz/argz_add_sep.c: Ditto.
        * libc/argz/argz_append.c libc/argz/argz_count.c: Ditto.
        * libc/argz/argz_create.c libc/argz/argz_create_sep.c: Ditto.
        * libc/argz/argz_delete.c libc/argz/argz_extract.c: Ditto.
        * libc/argz/argz_insert.c libc/argz/argz_next.c: Ditto.
        * libc/argz/argz_replace.c libc/argz/argz_stringify.c: Ditto.
        * libc/argz/envz_add.c libc/argz/envz_entry.c: Ditto.
        * libc/argz/envz_get.c libc/argz/envz_merge.c: Ditto.
        * libc/argz/envz_remove.c libc/argz/envz_strip.c: Ditto.
        * libc/locale/nl_langinfo.c libc/misc/ffs.c: Ditto.
        * libc/posix/closedir.c libc/posix/creat.c: Ditto.
        * libc/posix/execl.c libc/posix/execle.c: Ditto.
        * libc/posix/execlp.c libc/posix/execve.c: Ditto.
        * libc/posix/isatty.c libc/posix/opendir.c: Ditto.
        * libc/posix/popen.c libc/posix/readdir.c: Ditto.
        * libc/posix/readdir_r.c libc/posix/rewinddir.c: Ditto.
        * libc/posix/scandir.c libc/posix/seekdir.c: Ditto.
        * libc/posix/telldir.c libc/search/hcreate.c: Ditto.
        * libc/search/tdelete.c libc/search/tdestroy.c: Ditto.
        * libc/search/tfind.c libc/search/tsearch.c: Ditto.
        * libc/search/twalk.c libc/signal/signal.c: Ditto.
2003-06-06 19:57:51 +00:00

68 lines
1.7 KiB
C

/* $NetBSD: tdelete.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: tdelete.c,v 1.2 1999/09/16 11:45:37 lukem Exp $");
#endif /* LIBC_SCCS and not lint */
#endif
#include <assert.h>
#define _SEARCH_PRIVATE
#include <search.h>
#include <stdlib.h>
/* delete node with given key */
void *
_DEFUN(tdelete, (vkey, vrootp, compar),
const void *vkey _AND /* key to be deleted */
void **vrootp _AND /* address of the root of tree */
int (*compar)(const void *, const void *))
{
node_t **rootp = (node_t **)vrootp;
node_t *p, *q, *r;
int cmp;
if (rootp == NULL || (p = *rootp) == NULL)
return NULL;
while ((cmp = (*compar)(vkey, (*rootp)->key)) != 0) {
p = *rootp;
rootp = (cmp < 0) ?
&(*rootp)->llink : /* follow llink branch */
&(*rootp)->rlink; /* follow rlink branch */
if (*rootp == NULL)
return NULL; /* key not found */
}
r = (*rootp)->rlink; /* D1: */
if ((q = (*rootp)->llink) == NULL) /* Left NULL? */
q = r;
else if (r != NULL) { /* Right link is NULL? */
if (r->llink == NULL) { /* D2: Find successor */
r->llink = q;
q = r;
} else { /* D3: Find NULL link */
for (q = r->llink; q->llink != NULL; q = r->llink)
r = q;
r->llink = q->rlink;
q->llink = (*rootp)->llink;
q->rlink = (*rootp)->rlink;
}
}
free(*rootp); /* D4: Free node */
*rootp = q; /* link parent to new node */
return p;
}