1 /* strerror.c --- ANSI C compatible system error routine 2 3 Copyright (C) 1986, 1988, 1989, 1991, 2002, 2003, 2006 Free 4 Software Foundation, Inc. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software Foundation, 18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 #include <config.h> 21 22 #if !HAVE_STRERROR 23 24 #include <limits.h> 25 26 /* Don't include <stdio.h>, since it may or may not declare 27 sys_errlist and its declarations may collide with ours. Just 28 declare the stuff that we need directly. Standard hosted C89 29 implementations define strerror and they don't need this strerror 30 function, so take some liberties with the standard to cater to 31 ancient or limited freestanding implementations. */ 32 int sprintf (char *, char const *, ...); 33 extern int sys_nerr; 34 extern char *sys_errlist[]; 35 36 char * 37 strerror (int n) 38 { 39 static char const fmt[] = "Unknown error (%d)"; 40 static char mesg[sizeof fmt + sizeof n * CHAR_BIT / 3]; 41 42 if (n < 0 || n >= sys_nerr) 43 { 44 sprintf (mesg, fmt, n); 45 return mesg; 46 } 47 else 48 return sys_errlist[n]; 49 } 50 51 #else 52 53 /* This declaration is solely to ensure that after preprocessing 54 this file is never empty. */ 55 typedef int dummy; 56 57 #endif 58