freebsd-dev/lib/libc/string/strerror.c
Bruce Evans 5ec11cf0bb Fix printing of weird errno's: negative values were printed as large
unsigned's; null termination was only guaranteed for the first call.

Fix lint: don't declare externs internally; they were both out of date.
1994-09-05 13:37:43 +00:00

72 lines
2.6 KiB
C

/*
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)strerror.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#include <string.h>
char *
strerror(num)
int num;
{
#define UPREFIX "Unknown error: "
static char ebuf[40] = UPREFIX; /* 64-bit number + slop */
register unsigned int errnum;
register char *p, *t;
char tmp[40];
errnum = num; /* convert to unsigned */
if (errnum < sys_nerr)
return ((char *)sys_errlist[errnum]);
/* Do this by hand, so we don't link to stdio(3). */
t = tmp;
if (num < 0)
errnum = -errnum;
do {
*t++ = "0123456789"[errnum % 10];
} while (errnum /= 10);
if (num < 0)
*t++ = '-';
for (p = ebuf + sizeof(UPREFIX) - 1;;) {
*p++ = *--t;
if (t <= tmp)
break;
}
*p = '\0';
return (ebuf);
}