mirror of
https://git.FreeBSD.org/src.git
synced 2024-11-26 07:55:01 +00:00
4ef9bd22ed
Back in 2015 when I reimplemented these functions to use an AVL tree, I was annoyed by the weakness of the typing of these functions. Both tree nodes and keys are represented by 'void *', meaning that things like the documentation for these functions are an absolute train wreck. To make things worse, users of these functions need to cast the return value of tfind()/tsearch() from 'void *' to 'type_of_key **' in order to access the key. Technically speaking such casts violate aliasing rules. I've observed actual breakages as a result of this by enabling features like LTO. I've filed a bug report at the Austin Group. Looking at the way the bug got resolved, they made a pretty good step in the right direction. A new type 'posix_tnode' has been added to correspond to tree nodes. It is still defined as 'void' for source-level compatibility, but in the very far future it could be replaced by a proper structure type containing a key pointer. MFC after: 1 month Differential Revision: https://reviews.freebsd.org/D8205
86 lines
1.7 KiB
C
86 lines
1.7 KiB
C
/*-
|
|
* Written by J.T. Conklin <jtc@NetBSD.org>
|
|
* Public domain.
|
|
*
|
|
* $NetBSD: search.h,v 1.16 2005/02/03 04:39:32 perry Exp $
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _SEARCH_H_
|
|
#define _SEARCH_H_
|
|
|
|
#include <sys/cdefs.h>
|
|
#include <sys/_types.h>
|
|
|
|
#ifndef _SIZE_T_DECLARED
|
|
typedef __size_t size_t;
|
|
#define _SIZE_T_DECLARED
|
|
#endif
|
|
|
|
typedef struct entry {
|
|
char *key;
|
|
void *data;
|
|
} ENTRY;
|
|
|
|
typedef enum {
|
|
FIND, ENTER
|
|
} ACTION;
|
|
|
|
typedef enum {
|
|
preorder,
|
|
postorder,
|
|
endorder,
|
|
leaf
|
|
} VISIT;
|
|
|
|
#ifdef _SEARCH_PRIVATE
|
|
typedef struct __posix_tnode {
|
|
void *key;
|
|
struct __posix_tnode *llink, *rlink;
|
|
signed char balance;
|
|
} posix_tnode;
|
|
|
|
struct que_elem {
|
|
struct que_elem *next;
|
|
struct que_elem *prev;
|
|
};
|
|
#else
|
|
typedef void posix_tnode;
|
|
#endif
|
|
|
|
#if __BSD_VISIBLE
|
|
struct hsearch_data {
|
|
struct __hsearch *__hsearch;
|
|
};
|
|
#endif
|
|
|
|
__BEGIN_DECLS
|
|
int hcreate(size_t);
|
|
void hdestroy(void);
|
|
ENTRY *hsearch(ENTRY, ACTION);
|
|
void insque(void *, void *);
|
|
void *lfind(const void *, const void *, size_t *, size_t,
|
|
int (*)(const void *, const void *));
|
|
void *lsearch(const void *, void *, size_t *, size_t,
|
|
int (*)(const void *, const void *));
|
|
void remque(void *);
|
|
void *tdelete(const void * __restrict, posix_tnode ** __restrict,
|
|
int (*)(const void *, const void *));
|
|
posix_tnode *
|
|
tfind(const void *, posix_tnode * const *,
|
|
int (*)(const void *, const void *));
|
|
posix_tnode *
|
|
tsearch(const void *, posix_tnode **,
|
|
int (*)(const void *, const void *));
|
|
void twalk(const posix_tnode *, void (*)(const posix_tnode *, VISIT, int));
|
|
|
|
#if __BSD_VISIBLE
|
|
int hcreate_r(size_t, struct hsearch_data *);
|
|
void hdestroy_r(struct hsearch_data *);
|
|
int hsearch_r(ENTRY, ACTION, ENTRY **, struct hsearch_data *);
|
|
#endif
|
|
|
|
__END_DECLS
|
|
|
|
#endif /* !_SEARCH_H_ */
|