OpenBSD-4.6/usr.bin/mail/tty.c
/* $OpenBSD: tty.c,v 1.18 2005/07/11 14:08:23 millert Exp $ */
/* $NetBSD: tty.c,v 1.7 1997/07/09 05:25:46 mikel 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.
*/
#ifndef lint
#if 0
static const char sccsid[] = "@(#)tty.c 8.2 (Berkeley) 4/20/95";
#else
static const char rcsid[] = "$OpenBSD: tty.c,v 1.18 2005/07/11 14:08:23 millert Exp $";
#endif
#endif /* not lint */
/*
* Mail -- a mail program
*
* Generally useful tty stuff.
*/
#include "rcv.h"
#include "extern.h"
#include <sys/ioctl.h>
#include <errno.h>
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
static volatile sig_atomic_t ttysignal; /* Interrupted by a signal? */
/*
* Read all relevant header fields.
*/
int
grabh(struct header *hp, int gflags)
{
struct termios ttybuf;
#ifndef TIOCSTI
struct sigaction savequit;
#else
# ifdef TIOCEXT
int extproc;
int flag;
# endif /* TIOCEXT */
#endif
struct sigaction savetstp;
struct sigaction savettou;
struct sigaction savettin;
struct sigaction act;
char *s;
int error;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_RESTART;
act.sa_handler = SIG_DFL;
(void)sigaction(SIGTSTP, &act, &savetstp);
(void)sigaction(SIGTTOU, &act, &savettou);
(void)sigaction(SIGTTIN, &act, &savettin);
error = 1;
#ifndef TIOCSTI
ttyset = 0;
#endif
if (tcgetattr(fileno(stdin), &ttybuf) < 0) {
warn("tcgetattr");
return(-1);
}
c_erase = ttybuf.c_cc[VERASE];
c_kill = ttybuf.c_cc[VKILL];
#ifndef TIOCSTI
ttybuf.c_cc[VERASE] = 0;
ttybuf.c_cc[VKILL] = 0;
act.sa_handler = SIG_IGN;
if (sigaction(SIGQUIT, &act, &savequit) == 0 &&
savequit.sa_handler == SIG_DFL)
(void)sigaction(SIGQUIT, &savequit, NULL);
#else
# ifdef TIOCEXT
extproc = ((ttybuf.c_lflag & EXTPROC) ? 1 : 0);
if (extproc) {
flag = 0;
if (ioctl(fileno(stdin), TIOCEXT, &flag) < 0)
warn("TIOCEXT: off");
}
# endif /* TIOCEXT */
#endif
if (gflags & GTO) {
#ifndef TIOCSTI
if (!ttyset && hp->h_to != NULL)
ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
#endif
s = readtty("To: ", detract(hp->h_to, 0));
if (s == NULL)
goto out;
hp->h_to = extract(s, GTO);
}
if (gflags & GSUBJECT) {
#ifndef TIOCSTI
if (!ttyset && hp->h_subject != NULL)
ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
#endif
s = readtty("Subject: ", hp->h_subject);
if (s == NULL)
goto out;
hp->h_subject = s;
}
if (gflags & GCC) {
#ifndef TIOCSTI
if (!ttyset && hp->h_cc != NULL)
ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
#endif
s = readtty("Cc: ", detract(hp->h_cc, 0));
if (s == NULL)
goto out;
hp->h_cc = extract(s, GCC);
}
if (gflags & GBCC) {
#ifndef TIOCSTI
if (!ttyset && hp->h_bcc != NULL)
ttyset++, tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
#endif
s = readtty("Bcc: ", detract(hp->h_bcc, 0));
if (s == NULL)
goto out;
hp->h_bcc = extract(s, GBCC);
}
error = 0;
out:
(void)sigaction(SIGTSTP, &savetstp, NULL);
(void)sigaction(SIGTTOU, &savettou, NULL);
(void)sigaction(SIGTTIN, &savettin, NULL);
#ifndef TIOCSTI
ttybuf.c_cc[VERASE] = c_erase;
ttybuf.c_cc[VKILL] = c_kill;
if (ttyset)
tcsetattr(fileno(stdin), TCSADRAIN, &ttybuf);
(void)sigaction(SIGQUIT, &savequit, NULL);
#else
# ifdef TIOCEXT
if (extproc) {
flag = 1;
if (ioctl(fileno(stdin), TIOCEXT, &flag) < 0)
warn("TIOCEXT: on");
}
# endif /* TIOCEXT */
#endif
return(error);
}
/*
* Read up a header from standard input.
* The source string has the preliminary contents to
* be read.
*
*/
char *
readtty(char *pr, char *src)
{
struct sigaction act, saveint;
char ch, canonb[BUFSIZ];
char *cp, *cp2;
sigset_t oset;
int c;
fputs(pr, stdout);
fflush(stdout);
if (src != NULL && strlen(src) > sizeof(canonb) - 2) {
puts("too long to edit");
return(src);
}
#ifndef TIOCSTI
if (src != NULL)
cp = copy(src, canonb); /* safe, bounds checked above */
else
cp = copy("", canonb);
fputs(canonb, stdout);
fflush(stdout);
#else
cp = src == NULL ? "" : src;
while ((c = *cp++) != '\0') {
if ((c_erase != _POSIX_VDISABLE && c == c_erase) ||
(c_kill != _POSIX_VDISABLE && c == c_kill)) {
ch = '\\';
ioctl(0, TIOCSTI, &ch);
}
ch = c;
ioctl(0, TIOCSTI, &ch);
}
cp = canonb;
*cp = 0;
#endif
sigemptyset(&act.sa_mask);
act.sa_flags = 0; /* Note: will not restart syscalls */
act.sa_handler = ttyint;
(void)sigaction(SIGINT, &act, &saveint);
act.sa_handler = ttystop;
(void)sigaction(SIGTSTP, &act, NULL);
(void)sigaction(SIGTTOU, &act, NULL);
(void)sigaction(SIGTTIN, &act, NULL);
(void)sigprocmask(SIG_UNBLOCK, &intset, &oset);
clearerr(stdin);
memset(cp, 0, canonb + sizeof(canonb) - cp);
for (cp2 = cp; cp2 < canonb + sizeof(canonb) - 1; ) {
c = getc(stdin);
switch (ttysignal) {
case SIGINT:
ttysignal = 0;
cp2 = NULL;
c = EOF;
/* FALLTHROUGH */
case 0:
break;
default:
ttysignal = 0;
goto redo;
}
if (c == EOF || c == '\n')
break;
*cp2++ = c;
}
act.sa_handler = SIG_DFL;
sigemptyset(&act.sa_mask);
act.sa_flags = SA_RESTART;
(void)sigprocmask(SIG_SETMASK, &oset, NULL);
(void)sigaction(SIGTSTP, &act, NULL);
(void)sigaction(SIGTTOU, &act, NULL);
(void)sigaction(SIGTTIN, &act, NULL);
(void)sigaction(SIGINT, &saveint, NULL);
if (cp2 == NULL)
return(NULL); /* user hit ^C */
*cp2 = '\0';
if (c == EOF && ferror(stdin)) {
redo:
cp = strlen(canonb) > 0 ? canonb : NULL;
clearerr(stdin);
/* XXX - make iterative, not recursive */
return(readtty(pr, cp));
}
#ifndef TIOCSTI
if (cp == NULL || *cp == '\0')
return(src);
cp2 = cp;
if (!ttyset)
return(strlen(canonb) > 0 ? savestr(canonb) : NULL);
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 (equal("", canonb))
return("");
return(savestr(canonb));
}
/*
* Receipt continuation.
*/
void
ttystop(int s)
{
struct sigaction act, oact;
sigset_t nset;
int save_errno;
/*
* Save old handler and set to default.
* Unblock receipt of 's' and then resend it.
*/
save_errno = errno;
(void)sigemptyset(&act.sa_mask);
act.sa_flags = SA_RESTART;
act.sa_handler = SIG_DFL;
(void)sigaction(s, &act, &oact);
(void)sigemptyset(&nset);
(void)sigaddset(&nset, s);
(void)sigprocmask(SIG_UNBLOCK, &nset, NULL);
(void)kill(0, s);
(void)sigprocmask(SIG_BLOCK, &nset, NULL);
(void)sigaction(s, &oact, NULL);
ttysignal = s;
errno = save_errno;
}
/*ARGSUSED*/
void
ttyint(int s)
{
ttysignal = s;
}