/*      $NetBSD: tty.c,v 1.29 2011/09/16 15:39:27 joerg Exp $   */

/*
 * Copyright (c) 1980, 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. 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.
 */

#include <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)tty.c       8.2 (Berkeley) 6/6/93";
#else
__RCSID("$NetBSD: tty.c,v 1.29 2011/09/16 15:39:27 joerg Exp $");
#endif
#endif /* not lint */

/*
 * Mail -- a mail program
 *
 * Generally useful tty stuff.
 */

#include "rcv.h"
#include "extern.h"
#ifdef USE_EDITLINE
# include "complete.h"
#endif
#include "sig.h"

static  jmp_buf tty_jmpbuf;             /* Place to go when interrupted */

#ifndef USE_EDITLINE
static  cc_t    c_erase;                /* Current erase char */
static  cc_t    c_kill;                 /* Current kill char */
# ifndef TIOCSTI
static  int     ttyset;                 /* We must now do erase/kill */
# endif
#endif /* USE_EDITLINE */

/*
 * Read up a header from standard input.
 * The source string has the preliminary contents to
 * be read.
 *
 * Returns: an salloc'ed copy of the line read if successful, or NULL
 * if no characters were read or if an error occurred.
 *
 */
#ifdef USE_EDITLINE
static char *
readtty(const char *pr, char *src)
{
        char *line;

        line = my_gets(&elm.string, pr, src);
        sig_check();
        if (line == NULL)
                (void)putc('\n', stdout);

        return line ? savestr(line) : __UNCONST("");
}

#else /* not USE_EDITLINE */

static char *
readtty(const char *pr, char *src)
{
        char canonb[LINESIZE];
        char *cp, *cp2;
        int c;
#ifdef TIOCSTI
        char ch;
#endif

        (void)fputs(pr, stdout);
        (void)fflush(stdout);
        if (src != NULL && strlen(src) > sizeof(canonb) - 2) {
                (void)printf("too long to edit\n");
                return src;
        }
#ifndef TIOCSTI
        if (src != NULL)
                cp = copy(src, canonb);
        else
                cp = copy(__UNCONST(""), canonb);
        c = *cp;
        (void)fputs(canonb, stdout);
        (void)fflush(stdout);
#else
        cp = src == NULL ? __UNCONST("") : src;
        while ((c = *cp++) != '\0') {
                if ((c_erase != _POSIX_VDISABLE && c == c_erase) ||
                    (c_kill != _POSIX_VDISABLE && c == c_kill)) {
                        ch = '\\';
                        (void)ioctl(0, TIOCSTI, &ch);
                }
                ch = c;
                (void)ioctl(0, TIOCSTI, &ch);
        }
        cp = canonb;
        *cp = '\0';
#endif
        clearerr(stdin);
        cp2 = cp;
        while (cp2 < canonb + sizeof(canonb) - 1) {
                c = getc(stdin);
                sig_check();
                if (c == EOF) {
                        if (feof(stdin))
                                (void)putc('\n', stdout);
                        break;
                }
                if (c == '\n')
                        break;
                *cp2++ = c;
        }
        *cp2 = '\0';

        if (c == EOF && ferror(stdin)) {
                cp = strlen(canonb) > 0 ? canonb : NULL;
                clearerr(stdin);
                return readtty(pr, cp);
        }
#ifndef TIOCSTI
        if (cp == NULL || *cp == '\0')
                return src;
        if (ttyset == 0)
                return strlen(canonb) > 0 ? savestr(canonb) : NULL;

        /*
         * Do erase and kill.
         */
        cp2 = cp;
        while (*cp != '\0') {
                c = *cp++;
                if (c_erase != _POSIX_VDISABLE && c == c_erase) {
                        if (cp2 == canonb)
                                continue;
                        if (cp2[-1] == '\\') {
                                cp2[-1] = c;
                                continue;
                        }
                        cp2--;
                        continue;
                }
                if (c_kill != _POSIX_VDISABLE && c == c_kill) {
                        if (cp2 == canonb)
                                continue;
                        if (cp2[-1] == '\\') {
                                cp2[-1] = c;
                                continue;
                        }
                        cp2 = canonb;
                        continue;
                }
                *cp2++ = c;
        }
        *cp2 = '\0';
#endif
        if (canonb[0] == '\0')
                return __UNCONST("");
        return savestr(canonb);
}
#endif /* USE_EDITLINE */

#ifdef USE_EDITLINE
# define save_erase_and_kill(t)         0
#else
static int
save_erase_and_kill(struct termios *t)
{

# ifndef TIOCSTI
        ttyset = 0;
#endif
        if (tcgetattr(fileno(stdin), t) == -1) {
                warn("tcgetattr");
                return -1;
        }
        c_erase = t->c_cc[VERASE];
        c_kill = t->c_cc[VKILL];
        return 0;
}
#endif

#if defined(USE_EDITLINE) || defined(TIOCSTI)
# define disable_erase_and_kill(t)
#else
static void
disable_erase_and_kill(struct termios *t)
{

        if (ttyset == 0) {
                ttyset = 1;
                t->c_cc[VERASE] = _POSIX_VDISABLE;
                t->c_cc[VKILL] = _POSIX_VDISABLE;
                (void)tcsetattr(fileno(stdin), TCSADRAIN, t);
        }
}
#endif

#if defined(USE_EDITLINE) || defined(TIOCSTI)
# define restore_erase_and_kill(t)
#else
static void
restore_erase_and_kill(struct termios *t)
{

        if (ttyset != 0) {
                ttyset = 0;
                t->c_cc[VERASE] = c_erase;
                t->c_cc[VKILL] = c_kill;
                (void)tcsetattr(fileno(stdin), TCSADRAIN, t);
        }
}
#endif

/*
 * Do a shell-like extraction of a line
 * and make a list of name from it.
 * Return the list or NULL if none found.
 */
static struct name *
shextract(char *line, int ntype)
{
        struct name *begin, *np, *t;
        char *argv[MAXARGC];
        size_t argc, i;

        begin = NULL;
        if (line) {
                np = NULL;
                argc = getrawlist(line, argv, (int)__arraycount(argv));
                for (i = 0; i < argc; i++) {
                        t = nalloc(argv[i], ntype);
                        if (begin == NULL)
                                begin = t;
                        else
                                np->n_flink = t;
                        t->n_blink = np;
                        np = t;
                }
        }
        return begin;
}

/*ARGSUSED*/
__dead static void
tty_sigint(int signo __unused)
{

        longjmp(tty_jmpbuf, 1);
}

/*
 * Read all relevant header fields.
 * Returns 0 on success; 1 if there was an error or signal.
 */
PUBLIC int
grabh(struct header *hp, int gflags)
{
        sig_t volatile old_sigint;
        int retval;
#ifndef USE_EDITLINE
        struct termios ttybuf;
# if defined(TIOCSTI) && defined(TIOCEXT)
        int extproc;
# endif

        if (save_erase_and_kill(&ttybuf))
                return -1;

# if defined(TIOCSTI) && defined(TIOCEXT)
        extproc = ((ttybuf.c_lflag & EXTPROC) ? 1 : 0);
        if (extproc) {
                int flag;

                flag = 0;
                if (ioctl(fileno(stdin), TIOCEXT, &flag) == -1)
                        warn("TIOCEXT: off");
        }
# endif
#endif /* USE_EDITLINE */

        sig_check();
        old_sigint = sig_signal(SIGINT, tty_sigint);

        /* return here if we detect a SIGINT */
        if ((retval = setjmp(tty_jmpbuf)) != 0) {
                (void)putc('\n', stdout);
                goto out;
        }

        /*
         * Do this irrespective of whether the initial string is empty.
         * Otherwise, the editing is inconsistent.
         */
        disable_erase_and_kill(&ttybuf);

        if (gflags & GTO) {
                hp->h_to =
                    extract(readtty("To: ", detract(hp->h_to, 0)), GTO);
        }
        if (gflags & GSUBJECT) {
                hp->h_subject = readtty("Subject: ", hp->h_subject);
        }
        if (gflags & GCC) {
                hp->h_cc =
                    extract(readtty("Cc: ", detract(hp->h_cc, 0)), GCC);
        }
        if (gflags & GBCC) {
                hp->h_bcc =
                    extract(readtty("Bcc: ", detract(hp->h_bcc, 0)), GBCC);
        }
        if (gflags & GSMOPTS) {
                hp->h_smopts =
                    shextract(readtty("Smopts: ", detract(hp->h_smopts, 0)),
                        GSMOPTS);
        }
#ifdef MIME_SUPPORT
        if (gflags & GSMOPTS) { /* XXX - Use a new flag for this? */
                if (hp->h_attach) {
                        struct attachment *ap;
                        int i;

                        i = 0;
                        for (ap = hp->h_attach; ap; ap = ap->a_flink)
                                i++;
                        (void)printf("Attachment%s: %d\n", i > 1 ? "s" : "", i);
                }
        }
#endif
 out:
        restore_erase_and_kill(&ttybuf);

#ifndef USE_EDITLINE
# if defined(TIOCSTI) && defined(TIOCEXT)
        if (extproc) {
                int flag;
                flag = 1;
                if (ioctl(fileno(stdin), TIOCEXT, &flag) == -1)
                        warn("TIOCEXT: on");
        }
# endif
#endif
        (void)sig_signal(SIGINT, old_sigint);
        sig_check();
        return retval;
}