code.delx.au - gnu-emacs/blob - test/etags/c-src/sysdep.h

   1 /* Copyright (C) 1992-1993, 2016 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