sysdeps/mach/_strerror.c

   1 /* Copyright (C) 1993, 1995 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 <stdio.h>
  20 #include <string.h>
  21 #include <mach/error.h>
  22 #include <errorlib.h>
  23 #include "../stdio/_itoa.h"
  24
  25 /* Return a string describing the errno code in ERRNUM.  */
  26 char *
  27 _strerror_internal (int errnum, char *buf, size_t buflen)
  28 {
  29   int system;
  30   int sub;
  31   int code;
  32   const struct error_system *es;
  33   extern void __mach_error_map_compat (int *);
  34
  35   __mach_error_map_compat (&errnum);
  36
  37   system = err_get_system (errnum);
  38   sub = err_get_sub (errnum);
  39   code = err_get_code (errnum);
  40
  41   if (system > err_max_system || ! __mach_error_systems[system].bad_sub)
  42     {
  43       static const char unk[] = "Error in unknown error system: ";
  44       char *p = buf + buflen;
  45       *p-- = '\0';
  46       p = _itoa (errnum, p, 16, 1);
  47       p -= sizeof unk - 1;
  48       return memcpy (p, unk, sizeof unk - 1);
  49     }
  50
  51   es = &__mach_error_systems[system];
  52
  53   if (sub >= es->max_sub)
  54     return (char *) es->bad_sub;
  55
  56   if (code >= es->subsystem[sub].max_code)
  57     {
  58       static const char unk[] = "Unknown error ";
  59       char *p = buf + buflen;
  60       size_t len = strlen (es->subsystem[sub].subsys_name);
  61       *p-- = '\0';
  62       p = _itoa (errnum, p, 16, 1);
  63       *p-- = ' ';
  64       p = memcpy (p - len, es->subsystem[sub].subsys_name, len);
  65       return memcpy (p - sizeof unk - 1, unk, sizeof unk - 1);
  66     }
  67
  68   return (char *) es->subsystem[sub].codes[code];
  69 }