sysdeps/unix/i386/sysdep.S

   1 /* Copyright (C) 1991-2016 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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <http://www.gnu.org/licenses/>.  */
  17
  18 #include <sysdep.h>
  19 #define _ERRNO_H
  20 #include <bits/errno.h>
  21
  22 #if IS_IN (rtld)
  23 # include <dl-sysdep.h>         /* Defines RTLD_PRIVATE_ERRNO.  */
  24 #endif
  25
  26 .globl C_SYMBOL_NAME(errno)
  27 .globl syscall_error
  28
  29 __syscall_error:
  30 #if defined (EWOULDBLOCK_sys) && EWOULDBLOCK_sys != EAGAIN
  31         /* We translate the system's EWOULDBLOCK error into EAGAIN.
  32            The GNU C library always defines EWOULDBLOCK==EAGAIN.
  33            EWOULDBLOCK_sys is the original number.  */
  34         cmpl $EWOULDBLOCK_sys, %eax /* Is it the old EWOULDBLOCK?  */
  35         jne notb                /* Branch if not.  */
  36         movl $EAGAIN, %eax      /* Yes; translate it to EAGAIN.  */
  37 notb:
  38 #endif
  39 #ifndef PIC
  40 # ifndef NO_TLS_DIRECT_SEG_REFS
  41         movl %eax, %gs:C_SYMBOL_NAME(errno@NTPOFF)
  42 # else
  43         movl %gs:0, %ecx
  44         movl %eax, C_SYMBOL_NAME(errno@NTPOFF)(%ecx)
  45 # endif
  46 #else
  47         /* The caller has pushed %ebx and then set it up to
  48            point to the GOT before calling us through the PLT.  */
  49         movl C_SYMBOL_NAME(errno@GOTNTPOFF)(%ebx), %ecx
  50
  51         /* Pop %ebx value saved before jumping here.  */
  52         popl %ebx
  53 # ifndef NO_TLS_DIRECT_SEG_REFS
  54         addl %gs:0, %ecx
  55         movl %eax, (%ecx)
  56 # else
  57         movl %eax, %gs:0(%ecx)
  58 # endif
  59 #endif
  60         movl $-1, %eax
  61         ret
  62
  63 #undef  __syscall_error
  64 END (__syscall_error)