1 /* Copyright (C) 1992-1993, 2016-2023 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Library General Public License as 6 published by the Free Software Foundation; either version 2 of the 7 License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Library General Public License for more details. 13 14 You should have received a copy of the GNU Library General Public 15 License along with the GNU C Library; see the file COPYING.LIB. If 16 not, write to the Free Software Foundation, Inc., 675 Mass Ave, 17 Cambridge, MA 02139, USA. */ 18 19 #include <sysdeps/unix/sysdep.h> 20 21 #define ENTRY(name) \ 22 .globl _##name; \ 23 .align 2; \ 24 _##name##: 25 26 #define PSEUDO(name, syscall_name, args) \ 27 .text; \ 28 .globl syscall_error; \ 29 ENTRY (name) \ 30 XCHG_##args 31 movl $SYS_##syscall_name, %eax; \ 32 int $0x80; \ 33 test %eax, %eax; \ 34 jl syscall_error; \ 35 XCHG_##args 36 37 /* Linux takes system call arguments in registers: 38 1: %ebx 39 2: %ecx 40 3: %edx 41 4: %esi 42 5: %edi 43 We put the arguments into registers from the stack, 44 and save the registers, by using the 386 `xchg' instruction 45 to swap the values in both directions. */ 46 47 #define XCHG_0 /* No arguments to frob. */ 48 #define XCHG_1 xchg 8(%esp), %ebx; XCHG_0 49 #define XCHG_2 xchg 12(%esp), %ecx; XCHG_1 50 #define XCHG_3 xchg 16(%esp), %edx; XCHG_2 51 #define XCHG_4 xchg 20(%esp), %esi; XCHG_3 52 #define XCHG_5 xchg 24(%esp), %edi; XCHG_3 53 54 #define r0 %eax /* Normal return-value register. */ 55 #define r1 %edx /* Secondary return-value register. */ 56 #define scratch %ecx /* Call-clobbered register for random use. */ 57 #define MOVE(x,y) movl x, y