/*
 * SYS/VARSYM.H
 *
 *      Implements structures used for variant symlink support.
 * 
 * $DragonFly: src/sys/sys/varsym.h,v 1.7 2008/02/23 00:59:23 swildner Exp $
 */

#ifndef _SYS_VARSYM_H_
#define _SYS_VARSYM_H_

#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)

#ifndef _SYS_QUEUE_H_
#include <sys/queue.h>          /* TAILQ_* macros */
#endif

#include <sys/lock.h>

struct varsym {
    int         vs_refs;        /* a lot of sharing occurs */
    int         vs_namelen;
    char        *vs_name;       /* variable name */
    char        *vs_data;       /* variable contents */
};

typedef struct varsym   *varsym_t;

struct varsyment {
    TAILQ_ENTRY(varsyment) ve_entry;
    varsym_t    ve_sym;
};

struct varsymset {
    TAILQ_HEAD(, varsyment) vx_queue;
    int         vx_setsize;
    struct lock vx_lock;
};

#endif  /* _KERNEL || _KERNEL_STRUCTURES */

#define VARSYM_PROC     1
#define VARSYM_USER     2
#define VARSYM_SYS      3
#define VARSYM_PRISON   4       /* used internally */

#define VARSYM_PROC_MASK        (1 << VARSYM_PROC)
#define VARSYM_USER_MASK        (1 << VARSYM_USER)
#define VARSYM_SYS_MASK         (1 << VARSYM_SYS)
#define VARSYM_ALL_MASK         (VARSYM_PROC_MASK|VARSYM_USER_MASK|VARSYM_SYS_MASK)

#define MAXVARSYM_NAME  64
#define MAXVARSYM_DATA  256
#define MAXVARSYM_SET   16384

#ifdef _KERNEL

varsym_t varsymfind(int mask, const char *name, int namelen);
int     varsymmake(int level, const char *name, const char *data);
void    varsymdrop(varsym_t var);
void    varsymset_init(struct varsymset *varsymset, struct varsymset *copy);
void    varsymset_clean(struct varsymset *varsymset);
int     varsymreplace(char *cp, int linklen, int maxlen);

#endif  /* _KERNEL */

#endif