sysdeps/unix/sysv/linux/m68k/sysdep.S

   1 /* Copyright (C) 1996 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 not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <sysdep.h>
  20
  21 /* Because the Linux version is in fact m68k/ELF and the start.? file
  22    for this system (sysdeps/m68k/elf/start.S) is also used by The Hurd
  23    and therefore this files must not contain the definition of the
  24    `errno' variable (I don't know why, ask Roland), we have to define
  25    it somewhere else.
  26
  27    ...and this place is here.  */
  28         .bss
  29         .globl errno
  30         .type errno,@object
  31 errno:  .space 4
  32         .size errno,4
  33         .globl _errno
  34         .type _errno,@object
  35 _errno = errno  /* This name is expected by hj's libc.so.5 startup code.  */
  36         .text
  37
  38 /* The following code is only used in the shared library when we
  39    compile the reentrant version.  Otherwise each system call defines
  40    each own version.  */
  41
  42 #ifndef PIC
  43
  44 /* The syscall stubs jump here when they detect an error.  */
  45
  46         .globl  __syscall_error
  47         .type   __syscall_error, @function
  48         .align  4
  49 __syscall_error:
  50         neg.l %d0
  51         move.l %d0, errno
  52 #ifdef _LIBC_REENTRANT
  53         move.l %d0, -(%sp)
  54         jbsr __errno_location
  55         move.l (%sp)+, (%a0)
  56 #endif
  57         move.l #-1, %d0
  58         /* Copy return value to %a0 for syscalls that are declared to
  59            return a pointer.  */
  60         move.l %d0, %a0
  61         rts
  62 END (__syscall_error)
  63 #endif /* PIC */
  64
  65         .weak __errno_location
  66         .type __errno_location,@function
  67         .align 4
  68 __errno_location:
  69         CALL_MCOUNT
  70 #ifdef PIC
  71         move.l  (%pc, errno@GOTPC), %a0
  72 #else
  73         lea     errno, %a0
  74 #endif
  75         rts
  76 END (__errno_location)