/*-
 * Copyright (c) 1982, 1988, 1991 The Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: src/sys/sys/sysent.h,v 1.27.2.5 2002/03/17 11:08:38 alfred Exp $
 */

#ifndef _SYS_SYSENT_H_
#define _SYS_SYSENT_H_

#ifndef _SYS_TYPES_H_
#include <sys/types.h>
#endif

struct lwp;
struct sysmsg;

typedef int     sy_call_t (struct sysmsg *sysmsg, const void *);

struct sysent {         /* system call table */
        int32_t   sy_narg;      /* number of arguments */
        uint32_t  sy_rsize;     /* sizeof(result) */
        sy_call_t *sy_call;     /* start function */
        sy_call_t *sy_abort;    /* abort function (only if start was async) */
};

struct image_params;
struct __sigset;
struct trapframe;
struct vnode;

struct sysentvec {
        int             sv_size;        /* number of entries */
        struct sysent   *sv_table;      /* pointer to sysent */
        int             sv_sigsize;     /* size of signal translation table */
        int             *sv_sigtbl;     /* signal translation table */
        int             sv_errsize;     /* size of errno translation table */
        int             *sv_errtbl;     /* errno translation table */
        int             (*sv_transtrap) (int, int);
                                        /* translate trap-to-signal mapping */
        int             (*sv_fixup) (register_t **, struct image_params *);
                                        /* stack fixup function */
        void            (*sv_sendsig) (void (*)(int), int,
                                           struct __sigset *, u_long);
                                        /* send signal */
        char            *sv_sigcode;    /* start of sigtramp code */
        int             *sv_szsigcode;  /* size of sigtramp code */
                                        /* prep syscall (must be MPSAFE) */
        char            *sv_name;       /* name of binary type */
        int             (*sv_coredump) (struct lwp *, int, struct vnode *,
                                            off_t);
                                        /* function to dump core, or NULL */
        int             (*sv_imgact_try) (struct image_params *);
        int             sv_minsigstksz; /* minimum signal stack size */
};

#ifdef _KERNEL
extern struct sysent sysent[];

#define NO_SYSCALL (-1)

struct module;

struct syscall_module_data {
       int     (*chainevh)(struct module *, int, void *); /* next handler */
       void    *chainarg;      /* arg for next event handler */
       int     *offset;         /* offset into sysent */
       struct  sysent *new_sysent; /* new sysent */
       struct  sysent old_sysent; /* old sysent */
};

#define SYSCALL_MODULE(name, offset, new_sysent, evh, arg)     \
static struct syscall_module_data name##_syscall_mod = {       \
       evh, arg, offset, new_sysent, { 0, NULL }               \
};                                                             \
                                                               \
static moduledata_t name##_mod = {                             \
       #name,                                                  \
       syscall_module_handler,                                 \
       &name##_syscall_mod                                     \
};                                                             \
DECLARE_MODULE(name, name##_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE)

#define SYSCALL_MODULE_HELPER(syscallname)              \
static int syscallname##_syscall = SYS_##syscallname;   \
static struct sysent syscallname##_sysent = {           \
    ((sizeof(struct syscallname ## _args ) - sizeof(struct sysmsg)) \
        / sizeof(register_t)),    \
    (sy_call_t *)& syscallname                          \
};                                                      \
SYSCALL_MODULE(syscallname,                             \
    & syscallname##_syscall, & syscallname##_sysent,    \
    NULL, NULL);

int    syscall_register (int *offset, struct sysent *new_sysent,
                             struct sysent *old_sysent);
int    syscall_deregister (int *offset, struct sysent *old_sysent);
int    syscall_module_handler (struct module *mod, int what, void *arg);

#endif /* _KERNEL */

#endif /* !_SYS_SYSENT_H_ */