rationalized handling of child processes, cleaned up mail1 some more

[unix-history] / usr / src / usr.bin / mail / tty.c

/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* 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 the University of California, Berkeley.  The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
static char sccsid[] = "@(#)tty.c       5.7 (Berkeley) %G%";
#endif /* not lint */

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

#include "rcv.h"

static  int     c_erase;                /* Current erase char */
static  int     c_kill;                 /* Current kill char */
static  int     hadcont;                /* Saw continue signal */
static  jmp_buf rewrite;                /* Place to go when continued */
#ifndef TIOCSTI
static  int     ttyset;                 /* We must now do erase/kill */
#endif

/*
* Read all relevant header fields.
*/

grabh(hp, gflags)
       struct header *hp;
{
       struct sgttyb ttybuf;
#ifndef TIOCSTI
       int (*saveint)(), (*savequit)();
#endif
       int (*savecont)();
       int errs;

       savecont = signal(SIGCONT, SIG_DFL);
       errs = 0;
#ifndef TIOCSTI
       ttyset = 0;
#endif
       if (gtty(fileno(stdin), &ttybuf) < 0) {
               perror("gtty");
               return(-1);
       }
       c_erase = ttybuf.sg_erase;
       c_kill = ttybuf.sg_kill;
#ifndef TIOCSTI
       ttybuf.sg_erase = 0;
       ttybuf.sg_kill = 0;
       if ((saveint = signal(SIGINT, SIG_IGN)) == SIG_DFL)
               signal(SIGINT, SIG_DFL);
       if ((savequit = signal(SIGQUIT, SIG_IGN)) == SIG_DFL)
               signal(SIGQUIT, SIG_DFL);
#endif
       if (gflags & GTO) {
#ifndef TIOCSTI
               if (!ttyset && hp->h_to != NIL)
                       ttyset++, stty(fileno(stdin), &ttybuf);
#endif
               hp->h_to =
                       extract(readtty("To: ", detract(hp->h_to, 0)), GTO);
       }
       if (gflags & GSUBJECT) {
#ifndef TIOCSTI
               if (!ttyset && hp->h_subject != NOSTR)
                       ttyset++, stty(fileno(stdin), &ttybuf);
#endif
               hp->h_subject = readtty("Subject: ", hp->h_subject);
       }
       if (gflags & GCC) {
#ifndef TIOCSTI
               if (!ttyset && hp->h_cc != NIL)
                       ttyset++, stty(fileno(stdin), &ttybuf);
#endif
               hp->h_cc =
                       extract(readtty("Cc: ", detract(hp->h_cc, 0)), GCC);
       }
       if (gflags & GBCC) {
#ifndef TIOCSTI
               if (!ttyset && hp->h_bcc != NIL)
                       ttyset++, stty(fileno(stdin), &ttybuf);
#endif
               hp->h_bcc =
                       extract(readtty("Bcc: ", detract(hp->h_bcc, 0)), GBCC);
       }
       signal(SIGCONT, savecont);
#ifndef TIOCSTI
       ttybuf.sg_erase = c_erase;
       ttybuf.sg_kill = c_kill;
       if (ttyset)
               stty(fileno(stdin), &ttybuf);
       signal(SIGINT, saveint);
       signal(SIGQUIT, savequit);
#endif
       return(errs);
}

/*
* Read up a header from standard input.
* The source string has the preliminary contents to
* be read.
*
*/

char *
readtty(pr, src)
       char pr[], src[];
{
       char ch, canonb[BUFSIZ];
       int c;
       register char *cp, *cp2;
       int ttycont();

       fputs(pr, stdout);
       fflush(stdout);
       if (src != NOSTR && strlen(src) > BUFSIZ - 2) {
               printf("too long to edit\n");
               return(src);
       }
#ifndef TIOCSTI
       if (src != NOSTR)
               cp = copy(src, canonb);
       else
               cp = copy("", canonb);
       fputs(canonb, stdout);
       fflush(stdout);
#else
       cp = src == NOSTR ? "" : src;
       while (c = *cp++) {
               if (c == c_erase || c == c_kill) {
                       ch = '\\';
                       ioctl(0, TIOCSTI, &ch);
               }
               ch = c;
               ioctl(0, TIOCSTI, &ch);
       }
       cp = canonb;
       *cp = 0;
#endif
       cp2 = cp;
       while (cp2 < canonb + BUFSIZ)
               *cp2++ = 0;
       cp2 = cp;
       if (setjmp(rewrite))
               goto redo;
       signal(SIGCONT, ttycont);
       clearerr(stdin);
       while (cp2 < canonb + BUFSIZ) {
               c = getc(stdin);
               if (c == EOF || c == '\n')
                       break;
               *cp2++ = c;
       }
       *cp2 = 0;
       signal(SIGCONT, SIG_DFL);
       if (c == EOF && ferror(stdin) && hadcont) {
redo:
               hadcont = 0;
               cp = strlen(canonb) > 0 ? canonb : NOSTR;
               clearerr(stdin);
               return(readtty(pr, cp));
       }
#ifndef TIOCSTI
       if (cp == NOSTR || *cp == '\0')
               return(src);
       cp2 = cp;
       if (!ttyset)
               return(strlen(canonb) > 0 ? savestr(canonb) : NOSTR);
       while (*cp != '\0') {
               c = *cp++;
               if (c == c_erase) {
                       if (cp2 == canonb)
                               continue;
                       if (cp2[-1] == '\\') {
                               cp2[-1] = c;
                               continue;
                       }
                       cp2--;
                       continue;
               }
               if (c == c_kill) {
                       if (cp2 == canonb)
                               continue;
                       if (cp2[-1] == '\\') {
                               cp2[-1] = c;
                               continue;
                       }
                       cp2 = canonb;
                       continue;
               }
               *cp2++ = c;
       }
       *cp2 = '\0';
#endif
       if (equal("", canonb))
               return(NOSTR);
       return(savestr(canonb));
}

/*
* Receipt continuation.
*/
/*ARGSUSED*/
ttycont(s)
{
       hadcont++;
       longjmp(rewrite, 1);
}