/*      $NetBSD: rumpclient.h,v 1.17 2017/05/11 18:44:50 christos Exp $ */

/*-
* Copyright (c) 2010 Antti Kantee.  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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/

#ifndef _RUMP_RUMPCLIENT_H_
#define _RUMP_RUMPCLIENT_H_

#include <sys/types.h>

#if !defined(__returns_twice)
#ifdef __GNUC__
#define __returns_twice __attribute__((__returns_twice__))
#else /* __GNUC__ */
#define __returns_twice
#endif /* !__GNUC__ */
#endif /* !__returns_twice */

#if !defined(RUMP_REGISTER_T)
# define RUMP_REGISTER_T long
# if !defined(_KERNEL) && !defined(_KMEMUSER) &&  \
   !defined(_KERNTYPES) && !defined(_STANDALONE)
typedef RUMP_REGISTER_T register_t;
# endif
#endif

struct rumpclient_fork;

#define rumpclient_vfork() rumpclient__dofork(vfork)

#ifdef __BEGIN_DECLS
__BEGIN_DECLS
#elif defined(__cplusplus)
extern "C" {
#endif

int rumpclient_syscall(int, const void *, size_t, register_t *);
int rumpclient_init(void);

struct rumpclient_fork *rumpclient_prefork(void);
int                     rumpclient_fork_init(struct rumpclient_fork *);
void                    rumpclient_fork_cancel(struct rumpclient_fork *);
void                    rumpclient_fork_vparent(struct rumpclient_fork *);

pid_t rumpclient_fork(void);
int rumpclient_exec(const char *, char *const [], char *const[]);
int rumpclient_daemon(int, int);

#define RUMPCLIENT_RETRYCONN_INFTIME ((time_t)-1)
#define RUMPCLIENT_RETRYCONN_ONCE ((time_t)-2)
#define RUMPCLIENT_RETRYCONN_DIE ((time_t)-3)
void rumpclient_setconnretry(time_t);

enum rumpclient_closevariant {
       RUMPCLIENT_CLOSE_CLOSE,
       RUMPCLIENT_CLOSE_DUP2,
       RUMPCLIENT_CLOSE_FCLOSEM
};
int rumpclient__closenotify(int *, enum rumpclient_closevariant);


/*
* vfork needs to be implemented as an inline to make everything
* run in the caller's stackframe.
*/
static __attribute__((__always_inline__)) __returns_twice inline pid_t
rumpclient__dofork(pid_t (*forkfn)(void))
{
       struct rumpclient_fork *rf;
       pid_t pid;
       int childran = 0;

       if (!(rf = rumpclient_prefork()))
               return -1;

       switch ((pid = forkfn())) {
       case -1:
               rumpclient_fork_cancel(rf);
               break;
       case 0:
               childran = 1;
               if (rumpclient_fork_init(rf) == -1)
                       pid = -1;
               break;
       default:
               /* XXX: multithreaded vforker?  do they exist? */
               if (childran)
                       rumpclient_fork_vparent(rf);
               break;
       }

       return pid;
}

#ifdef __END_DECLS
__END_DECLS
#elif defined(__cplusplus)
}
#endif

#endif /* _RUMP_RUMPCLIENT_H_ */