/*      $NetBSD: netbsd32_compat_16.c,v 1.10 2025/02/28 18:35:44 wiz Exp $      */

/*-
* Copyright (c) 2008 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Christos Zoulas.
*
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: netbsd32_compat_16.c,v 1.10 2025/02/28 18:35:44 wiz Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/module.h>
#include <sys/dirent.h>
#include <sys/exec.h>
#include <sys/proc.h>
#include <sys/lwp.h>
#include <sys/syscallargs.h>
#include <sys/syscallvar.h>

#include <compat/netbsd32/netbsd32.h>
#include <compat/netbsd32/netbsd32_syscall.h>
#include <compat/netbsd32/netbsd32_syscallargs.h>
#include <compat/netbsd32/netbsd32_conv.h>

struct uvm_object *emul_netbsd32_object;

#if defined(__amd64__) || defined(__arm__) || defined(__mips__) || defined(__sparc64__)
#define __HAVE_MD_NETBSD32_SIGRETURN14
#endif

#if defined(__amd64__) || defined(__arm__) || defined(__mips__) || defined(__powerpc__) || defined(__riscv__)
#define __HAVE_MD_NETBSD32_SIGCODE
#endif


#ifdef __HAVE_MD_NETBSD32_SIGRETURN14
static const struct syscall_package netbsd32_kern_sig_16_syscalls[] = {
       /* compat_16_netbsd32___sigreturn14 is in MD code! */
       { NETBSD32_SYS_compat_16_netbsd32___sigreturn14, 0,
           (sy_call_t *)compat_16_netbsd32___sigreturn14 },
       { 0, 0, NULL }
};
#endif

static int
compat_netbsd32_16_init(void)
{
#if defined(__HAVE_MD_NETBSD32_SIGRETURN14) || defined(__HAVE_MD_NETBSD32_SIGCODE)
       int error;
#endif

#ifdef __HAVE_MD_NETBSD32_SIGRETURN14
       error = syscall_establish(&emul_netbsd32,
           netbsd32_kern_sig_16_syscalls);
       if (error)
               return error;
#endif

#ifdef __HAVE_MD_NETBSD32_SIGCODE
       rw_enter(&exec_lock, RW_WRITER);
       emul_netbsd32.e_sigcode = netbsd32_sigcode;
       emul_netbsd32.e_esigcode = netbsd32_esigcode;
       emul_netbsd32.e_sigobject = &emul_netbsd32_object;
       error = exec_sigcode_alloc(&emul_netbsd);
       if (error) {
               emul_netbsd32.e_sigcode = NULL;
               emul_netbsd32.e_esigcode = NULL;
               emul_netbsd32.e_sigobject = NULL;
       }
       rw_exit(&exec_lock);
       if (error)
               return error;
       netbsd32_machdep_md_16_init();
#endif
       return 0;
}

static int
compat_netbsd32_16_fini(void)
{
#if defined(__HAVE_MD_NETBSD32_SIGRETURN14)
       proc_t *p;
       int error;
#endif

#ifdef __HAVE_MD_NETBSD32_SIGRETURN14
       error = syscall_disestablish(&emul_netbsd32,
           netbsd32_kern_sig_16_syscalls);
       if (error)
               return error;
       /*
        * Ensure sendsig_sigcontext() is not being used.
        * module_lock prevents the flag being set on any
        * further processes while we are here.  See
        * sigaction1() for the opposing half.
        */
       mutex_enter(&proc_lock);
       PROCLIST_FOREACH(p, &allproc) {
               if ((p->p_lflag & PL_SIGCOMPAT) != 0) {
                       break;
               }
       }
       mutex_exit(&proc_lock);
       if (p != NULL) {
               syscall_establish(&emul_netbsd32,
                   netbsd32_kern_sig_16_syscalls);
               return EBUSY;
       }
#endif

#ifdef __HAVE_MD_NETBSD32_SIGCODE
       rw_enter(&exec_lock, RW_WRITER);
       exec_sigcode_free(&emul_netbsd);
       emul_netbsd32.e_sigcode = NULL;
       emul_netbsd32.e_esigcode = NULL;
       emul_netbsd32.e_sigobject = NULL;
       rw_exit(&exec_lock);
       netbsd32_machdep_md_16_fini();
#endif
       return 0;
}

MODULE(MODULE_CLASS_EXEC, compat_netbsd32_16, "compat_netbsd32_20,compat_16");

static int
compat_netbsd32_16_modcmd(modcmd_t cmd, void *arg)
{
       switch (cmd) {
       case MODULE_CMD_INIT:
               return compat_netbsd32_16_init();

       case MODULE_CMD_FINI:
               return compat_netbsd32_16_fini();

       default:
               return ENOTTY;
       }
}