root/lib/libc/arch/amd64/SYS.h
/*      $OpenBSD: SYS.h,v 1.22 2023/12/10 16:45:50 deraadt Exp $        */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * 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.
 *
 *      from: @(#)SYS.h 5.5 (Berkeley) 5/7/91
 *      $NetBSD: SYS.h,v 1.5 2002/06/03 18:30:32 fvdl Exp $
 */

#include "DEFS.h"
#include <sys/syscall.h>

/* offsetof(struct tib, tib_errno) - offsetof(struct tib, __tib_tcb) */
#define TCB_OFFSET_ERRNO        32

#define SYSTRAP(x)                                                      \
        movl $(SYS_ ## x),%eax;                                         \
        movq %rcx, %r10;                                                \
97:     syscall;                                                        \
        PINSYSCALL(SYS_ ## x, 97b)

#define SYSENTRY(x)                                                     \
        SYSENTRY_HIDDEN(x);                                             \
        WEAK_ALIAS(x, _thread_sys_##x)
#define SYSENTRY_HIDDEN(x)                                              \
        ENTRY(_thread_sys_ ## x)

#define SYSCALL_END_HIDDEN(x)                                           \
        END(_thread_sys_ ## x);                                         \
        _HIDDEN_FALIAS(x,_thread_sys_##x);                              \
        END(_HIDDEN(x))
#define SYSCALL_END(x)          SYSCALL_END_HIDDEN(x); END(x)


#define SET_ERRNO                                                       \
        movl    %eax,%fs:(TCB_OFFSET_ERRNO);                            \
        movq    $-1, %rax
#define HANDLE_ERRNO                                                    \
        jnc     99f;                                                    \
        SET_ERRNO;                                                      \
        99:

#define _SYSCALL_NOERROR(x,y)                                           \
        SYSENTRY(x);                                                    \
        SYSTRAP(y)
#define _SYSCALL_HIDDEN_NOERROR(x,y)                                    \
        SYSENTRY_HIDDEN(x);                                             \
        SYSTRAP(y)

#define SYSCALL_NOERROR(x)                                              \
        _SYSCALL_NOERROR(x,x)

#define SYSCALL_HIDDEN(x)                                               \
        _SYSCALL_HIDDEN_NOERROR(x,x);                                   \
        HANDLE_ERRNO
#define SYSCALL(x)                                                      \
        _SYSCALL_NOERROR(x,x);                                          \
        HANDLE_ERRNO


#define PSEUDO_NOERROR(x,y)                                             \
        SYSENTRY(x);                                                    \
        RETGUARD_SETUP(_thread_sys_##x, r11);                           \
        RETGUARD_PUSH(r11);                                             \
        SYSTRAP(y);                                                     \
        RETGUARD_POP(r11);                                              \
        RETGUARD_CHECK(_thread_sys_##x, r11);                           \
        ret;                                                            \
        SYSCALL_END(x)

#define PSEUDO(x,y)                                                     \
        SYSENTRY(x);                                                    \
        RETGUARD_SETUP(_thread_sys_##x, r11);                           \
        RETGUARD_PUSH(r11);                                             \
        SYSTRAP(y);                                                     \
        HANDLE_ERRNO;                                                   \
        RETGUARD_POP(r11);                                              \
        RETGUARD_CHECK(_thread_sys_##x, r11);                           \
        ret;                                                            \
        SYSCALL_END(x)

#define PSEUDO_HIDDEN(x,y)                                              \
        SYSENTRY_HIDDEN(x);                                             \
        RETGUARD_SETUP(_thread_sys_##x, r11);                           \
        RETGUARD_PUSH(r11);                                             \
        SYSTRAP(y);                                                     \
        HANDLE_ERRNO;                                                   \
        RETGUARD_POP(r11);                                              \
        RETGUARD_CHECK(_thread_sys_##x , r11);                          \
        ret;                                                            \
        SYSCALL_END_HIDDEN(x)

#define RSYSCALL_NOERROR(x)                                             \
        PSEUDO_NOERROR(x,x)

#define RSYSCALL(x)                                                     \
        PSEUDO(x,x)
#define RSYSCALL_HIDDEN(x)                                              \
        PSEUDO_HIDDEN(x,x)