usr/src/lib/libc/net/herror.c

/*-
 * Copyright (c) 1987, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * %sccs.include.redist.c%
 * -
 * Portions Copyright (c) 1993 by Digital Equipment Corporation.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies, and that
 * the name of Digital Equipment Corporation not be used in advertising or
 * publicity pertaining to distribution of the document or software without
 * specific, written prior permission.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
 * WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS.   IN NO EVENT SHALL DIGITAL EQUIPMENT
 * CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 * -
 * --Copyright--
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)herror.c    8.1 (Berkeley) %G%";
static char rcsid[] = "$Id: herror.c,v 4.9.1.1 1993/05/02 23:14:35 vixie Rel $";
#endif /* LIBC_SCCS and not lint */

#include <sys/types.h>
#include <sys/uio.h>
#include <netdb.h>
#include <unistd.h>
#include <string.h>

char    *h_errlist[] = {
        "Error 0",
        "Unknown host",                         /* 1 HOST_NOT_FOUND */
        "Host name lookup failure",             /* 2 TRY_AGAIN */
        "Unknown server error",                 /* 3 NO_RECOVERY */
        "No address associated with name",      /* 4 NO_ADDRESS */
};
int     h_nerr = { sizeof(h_errlist)/sizeof(h_errlist[0]) };

extern int      h_errno;

/*
 * herror --
 *      print the error indicated by the h_errno value.
 */
void
herror(s)
        const char *s;
{
        struct iovec iov[4];
        register struct iovec *v = iov;

        if (s && *s) {
                v->iov_base = (char *)s;
                v->iov_len = strlen(s);
                v++;
                v->iov_base = ": ";
                v->iov_len = 2;
                v++;
        }
        v->iov_base = (u_int)h_errno < h_nerr ?
            h_errlist[h_errno] : "Unknown error";
        v->iov_len = strlen(v->iov_base);
        v++;
        v->iov_base = "\n";
        v->iov_len = 1;
        writev(STDERR_FILENO, iov, (v - iov) + 1);
}

char *
hstrerror(err)
        int err;
{
        return (u_int)err < h_nerr ? h_errlist[err] : "Unknown resolver error";
}