source: trunk/minix/commands/pax/tty_subs.c@ 21

/*-
 * Copyright (c) 1992 Keith Muller.
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Keith Muller of the University of California, San Diego.
 *
 * 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.
 * 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.
 */

#ifndef lint
#if 0
static char sccsid[] = "@(#)tty_subs.c  8.2 (Berkeley) 4/18/94";
#endif
#endif /* not lint */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include "pax.h"
#include "extern.h"
#include <stdarg.h>

/*
 * routines that deal with I/O to and from the user
 */

#define DEVTTY    "/dev/tty"      /* device for interactive i/o */
static FILE *ttyoutf = NULL;            /* output pointing at control tty */
static FILE *ttyinf = NULL;             /* input pointing at control tty */

/*
 * tty_init()
 *      try to open the controlling terminal (if any) for this process. if the
 *      open fails, future ops that require user input will get an EOF
 */

int
tty_init(void)
{
        int ttyfd;

        if ((ttyfd = open(DEVTTY, O_RDWR)) >= 0) {
                if ((ttyoutf = fdopen(ttyfd, "w")) != NULL) {
                        if ((ttyinf = fdopen(ttyfd, "r")) != NULL)
                                return(0);
                        (void)fclose(ttyoutf);
                }
                (void)close(ttyfd);
        }

        if (iflag) {
                paxwarn(1, "Fatal error, cannot open %s", DEVTTY);
                return(-1);
        }
        return(0);
}

/*
 * tty_prnt()
 *      print a message using the specified format to the controlling tty
 *      if there is no controlling terminal, just return.
 */

void
tty_prnt(const char *fmt, ...)
{
        va_list ap;
        if (ttyoutf == NULL)
                return;
        va_start(ap, fmt);
        (void)vfprintf(ttyoutf, fmt, ap);
        va_end(ap);
        (void)fflush(ttyoutf);
}

/*
 * tty_read()
 *      read a string from the controlling terminal if it is open into the
 *      supplied buffer
 * Return:
 *      0 if data was read, -1 otherwise.
 */

int
tty_read(char *str, int len)
{
        char *pt;

        if ((--len <= 0) || (ttyinf == NULL) || (fgets(str,len,ttyinf) == NULL))
                return(-1);
        *(str + len) = '\0';

        /*
         * strip off that trailing newline
         */
        if ((pt = strchr(str, '\n')) != NULL)
                *pt = '\0';
        return(0);
}

/*
 * paxwarn()
 *      write a warning message to stderr. if "set" the exit value of pax
 *      will be non-zero.
 */

void
paxwarn(int set, const char *fmt, ...)
{
        va_list ap;
        va_start(ap, fmt);
        if (set)
                exit_val = 1;
        /*
         * when vflag we better ship out an extra \n to get this message on a
         * line by itself
         */
        if (vflag && vfpart) {
                (void)fflush(listf);
                (void)fputc('\n', stderr);
                vfpart = 0;
        }
        (void)fprintf(stderr, "%s: ", argv0);
        (void)vfprintf(stderr, fmt, ap);
        va_end(ap);
        (void)fputc('\n', stderr);
}

/*
 * syswarn()
 *      write a warning message to stderr. if "set" the exit value of pax
 *      will be non-zero.
 */

void
syswarn(int set, int errnum, const char *fmt, ...)
{
        va_list ap;
        va_start(ap, fmt);
        if (set)
                exit_val = 1;
        /*
         * when vflag we better ship out an extra \n to get this message on a
         * line by itself
         */
        if (vflag && vfpart) {
                (void)fflush(listf);
                (void)fputc('\n', stderr);
                vfpart = 0;
        }
        (void)fprintf(stderr, "%s: ", argv0);
        (void)vfprintf(stderr, fmt, ap);
        va_end(ap);

        /*
         * format and print the errno
         */
        if (errnum > 0)
                (void)fprintf(stderr, " <%s>", strerror(errnum));
        (void)fputc('\n', stderr);
}