1 /*- 2 * Copyright (c) 1990 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * William Jolitz. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $OpenBSD: SYS.h,v 1.19 2014/06/04 20:13:49 matthew Exp $ 33 */ 34 35 #include <machine/asm.h> 36 #include <sys/syscall.h> 37 38 /* 39 * Design note: 40 * 41 * System calls entry points are really named _thread_sys_{syscall}, 42 * and weakly aliased to the name {syscall}. This allows the thread 43 * library to replace system calls at link time. 44 */ 45 46 /* Use both _thread_sys_{syscall} and [weak] {syscall}. */ 47 48 #define SYSENTRY(x) \ 49 ENTRY(_thread_sys_ ## x); \ 50 .weak _C_LABEL(x); \ 51 _C_LABEL(x) = _C_LABEL(_thread_sys_ ## x) 52 53 #define __DO_SYSCALL(x) \ 54 movl $(SYS_ ## x),%eax; \ 55 int $0x80 56 57 #define CERROR _C_LABEL(__cerror) 58 #define _CERROR _C_LABEL(___cerror) 59 #define CURBRK _C_LABEL(__curbrk) 60 61 /* perform a syscall */ 62 #define _SYSCALL_NOERROR(x,y) \ 63 SYSENTRY(x); \ 64 __DO_SYSCALL(y); 65 66 #define SYSCALL_NOERROR(x) \ 67 _SYSCALL_NOERROR(x,x) 68 69 /* perform a syscall, set errno */ 70 #ifdef __PIC__ 71 #define _SYSCALL(x,y) \ 72 .text; \ 73 .align 2; \ 74 2: PIC_PROLOGUE; \ 75 movl PIC_GOT(CERROR), %ecx; \ 76 PIC_EPILOGUE; \ 77 jmp *%ecx; \ 78 _SYSCALL_NOERROR(x,y) \ 79 jc 2b 80 #else 81 #define _SYSCALL(x,y) \ 82 .text; \ 83 .align 2; \ 84 2: \ 85 jmp PIC_PLT(CERROR); \ 86 _SYSCALL_NOERROR(x,y) \ 87 jc 2b 88 #endif 89 90 #define SYSCALL(x) \ 91 _SYSCALL(x,x) 92 93 /* perform a syscall, return */ 94 #define PSEUDO_NOERROR(x,y) \ 95 _SYSCALL_NOERROR(x,y); \ 96 ret 97 98 /* perform a syscall, set errno, return */ 99 #define PSEUDO(x,y) \ 100 _SYSCALL(x,y); \ 101 ret 102 103 /* perform a syscall with the same name, set errno, return */ 104 #define RSYSCALL(x) \ 105 PSEUDO(x,x); 106 107 .globl CERROR 108