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/* $Source: /u/mark/src/pax/RCS/ttyio.c,v $

 *

 * $Revision: 1.2 $

 *

 * ttyio.c - Terminal/Console I/O functions for all archive interfaces

 *

 * DESCRIPTION

 *

 *	These routines provide a consistent, general purpose interface to

 *	the user via the users terminal, if it is available to the

 *	process.

 *

 * AUTHOR

 *

 *     Mark H. Colburn, NAPS International (mark@jhereg.mn.org)

 *

 * Sponsored by The USENIX Association for public distribution. 

 *

 * Copyright (c) 1989 Mark H. Colburn.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms are permitted

 * provided that the above copyright notice is duplicated in all such 

 * forms and that any documentation, advertising materials, and other 

 * materials related to such distribution and use acknowledge that the 

 * software was developed * by Mark H. Colburn and sponsored by The 

 * USENIX Association. 

 *

 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR

 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED

 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

 *

 * $Log:	ttyio.c,v $

 * Revision 1.2  89/02/12  10:06:11  mark

 * 1.2 release fixes

 * 

 * Revision 1.1  88/12/23  18:02:39  mark

 * Initial revision

 * 

 */

#ifndef lint

static char *ident = "$Id: ttyio.c,v 1.2 89/02/12 10:06:11 mark Exp $";

static char *copyright = "Copyright (c) 1989 Mark H. Colburn.\nAll rights reserved.\n";

#endif /* ! lint */

/* Headers */

#include "pax.h"

/* open_tty - open the terminal for interactive queries

 *

 * DESCRIPTION

 *

 * 	Assumes that background processes ignore interrupts and that the

 *	open() or the isatty() will fail for processes which are not

 *	attached to terminals. Returns a file descriptor or -1 if

 *	unsuccessful. 

 *

 * RETURNS

 *

 *	Returns a file descriptor which can be used to read and write

 *	directly to the user's terminal, or -1 on failure.  

 *

 * ERRORS

 *

 *	If SIGINT cannot be ignored, or the open fails, or the newly opened

 *	terminal device is not a tty, then open_tty will return a -1 to the

 *	caller.

 */

#ifdef __STDC__

int open_tty(void)

#else

int open_tty()

#endif

{

    int             fd;		/* file descriptor for terminal */

    SIG_T         (*intr)();	/* used to restore interupts if signal fails */

    if ((intr = signal(SIGINT, SIG_IGN)) == SIG_IGN) {

	return (-1);

    }

    signal(SIGINT, intr);

    if ((fd = open(TTY, O_RDWR)) < 0) {

	return (-1);

    }

    if (isatty(fd)) {

	return (fd);

    }

    close(fd);

    return (-1);

}

/* nextask - ask a question and get a response

 *

 * DESCRIPTION

 *

 *	Give the user a prompt and wait for their response.  The prompt,

 *	located in "msg" is printed, then the user is allowed to type

 *	a response to the message.  The first "limit" characters of the

 *	user response is stored in "answer".

 *

 *	Nextask ignores spaces and tabs. 

 *

 * PARAMETERS

 *

 *	char *msg	- Message to display for user 

 *	char *answer	- Pointer to user's response to question 

 *	int limit	- Limit of length for user's response

 *

 * RETURNS

 *

 *	Returns the number of characters in the user response to the 

 *	calling function.  If an EOF was encountered, a -1 is returned to

 *	the calling function.  If an error occured which causes the read

 *	to return with a value of -1, then the function will return a

 *	non-zero return status to the calling process, and abort

 *	execution.

 */

#ifdef __STDC__

int nextask(char *msg, char *answer, int limit)

#else

int nextask(msg, answer, limit)

char           *msg;		/* message to display for user */

char           *answer;		/* pointer to user's response to question */

int             limit;		/* limit of length for user's response */

#endif

{

    int             idx;	/* index into answer for character input */

    int             got;	/* number of characters read */

    char            c;		/* character read */

    if (ttyf < 0) {

	fatal("/dev/tty Unavailable");

    }

    write(ttyf, msg, (uint) strlen(msg));

    idx = 0;

    while ((got = read(ttyf, &c, 1)) == 1) {

	if (c == '\n') {

	    break;

	} else if (c == ' ' || c == '\t') {

	    continue;

	} else if (idx < limit - 1) {

	    answer[idx++] = c;

	}

    }

    if (got == 0) {		/* got an EOF */

        return(-1);

    }

    if (got < 0) {

	fatal(strerror());

    }

    answer[idx] = '\0';

    return(0);

}

/* lineget - get a line from a given stream

 *

 * DESCRIPTION

 * 

 *	Get a line of input for the stream named by "stream".  The data on

 *	the stream is put into the buffer "buf".

 *

 * PARAMETERS

 *

 *	FILE *stream		- Stream to get input from 

 *	char *buf		- Buffer to put input into

 *

 * RETURNS

 *

 * 	Returns 0 if successful, -1 at EOF. 

 */

#ifdef __STDC__

int lineget(FILE *stream, char *buf)

#else

int lineget(stream, buf)

FILE           *stream;		/* stream to get input from */

char           *buf;		/* buffer to put input into */

#endif

{

    int             c;

    for (;;) {

	if ((c = getc(stream)) == EOF) {

	    return (-1);

	}

	if (c == '\n') {

	    break;

	}

	*buf++ = c;

    }

    *buf = '\0';

    return (0);

}

/* next - Advance to the next archive volume. 

 *

 * DESCRIPTION

 *

 *	Prompts the user to replace the backup medium with a new volume

 *	when the old one is full.  There are some cases, such as when

 *	archiving to a file on a hard disk, that the message can be a

 *	little surprising.  Assumes that background processes ignore

 *	interrupts and that the open() or the isatty() will fail for

 *	processes which are not attached to terminals. Returns a file

 *	descriptor or -1 if unsuccessful. 

 *

 * PARAMETERS

 *

 *	int mode	- mode of archive (READ, WRITE, PASS) 

 */

#ifdef __STDC__

void next(int mode)

#else

void next(mode)

int             mode;		/* mode of archive (READ, WRITE, PASS) */

#endif

{

    char            msg[200];	/* buffer for message display */ 

    char            answer[20];	/* buffer for user's answer */

    int             ret;

    close_archive();

    sprintf(msg, "%s: Ready for volume %u\n%s: Type \"go\" when ready to proceed (or \"quit\" to abort): \07",

		   myname, arvolume + 1, myname);

    for (;;) {

	ret = nextask(msg, answer, sizeof(answer));

	if (ret == -1 || strcmp(answer, "quit") == 0) {

	    fatal("Aborted");

	}

	if (strcmp(answer, "go") == 0 && open_archive(mode) == 0) {

	    break;

	}

    }

    warnarch("Continuing", (OFFSET) 0);

}