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mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-10 01:48:00 +00:00

Add experimental support for detecting BREAK on input and propagating it as

TS_BRK on output.  This is tested to the extent that other data survive the
escaping performed by PARMRK, at least on my system.  Actual passing on
of BREAK is as-yet untested.

[originally from svn r5779]
This commit is contained in:
Ben Harris 2005-05-14 22:01:10 +00:00
parent aa43d817d2
commit ab855b74c5

View File

@ -149,6 +149,17 @@ void ldisc_update(void *frontend, int echo, int edit)
mode.c_iflag &= ~IXON;
mode.c_iflag &= ~IXOFF;
}
/*
* Mark parity errors and (more important) BREAK on input. This
* is more complex than it need be because POSIX-2001 suggests
* that escaping of valid 0xff in the input stream is dependent on
* IGNPAR being clear even though marking of BREAK isn't. NetBSD
* 2.0 goes one worse and makes it dependent on INPCK too. We
* deal with this by forcing these flags into a useful state and
* then faking the state in which we found them in from_tty() if
* we get passed a parity or framing error.
*/
mode.c_iflag = (mode.c_iflag | INPCK | PARMRK) & ~IGNPAR;
tcsetattr(0, TCSANOW, &mode);
}
@ -380,6 +391,72 @@ int from_backend(void *frontend_handle, int is_stderr,
return osize + esize;
}
/*
* Handle data from a local tty in PARMRK format.
*/
static void from_tty(void *buf, unsigned len)
{
char *p, *q, *end;
static enum {NORMAL, FF, FF00} state = NORMAL;
p = buf; end = buf + len;
while (p < end) {
switch (state) {
case NORMAL:
if (*p == '\xff') {
p++;
state = FF;
} else {
q = memchr(p, '\xff', end - p);
if (q == NULL) q = end;
back->send(backhandle, p, q - p);
p = q;
}
break;
case FF:
if (*p == '\xff') {
back->send(backhandle, p, 1);
p++;
state = NORMAL;
} else if (*p == '\0') {
p++;
state = FF00;
} else abort();
break;
case FF00:
if (*p == '\0') {
back->special(backhandle, TS_BRK);
} else {
/*
* Pretend that PARMRK wasn't set. This involves
* faking what INPCK and IGNPAR would have done if
* we hadn't overridden them. Unfortunately, we
* can't do this entirely correctly because INPCK
* distinguishes between framing and parity
* errors, but PARMRK format represents both in
* the same way. We assume that parity errors are
* more common than framing errors, and hence
* treat all input errors as being subject to
* INPCK.
*/
if (orig_termios.c_iflag & INPCK) {
/* If IGNPAR is set, we throw away the character. */
if (!(orig_termios.c_iflag & IGNPAR)) {
/* PE/FE get passed on as NUL. */
*p = 0;
back->send(backhandle, p, 1);
}
} else {
/* INPCK not set. Assume we got a parity error. */
back->send(backhandle, p, 1);
}
}
p++;
state = NORMAL;
}
}
}
int signalpipe[2];
void sigwinch(int signum)
@ -926,7 +1003,10 @@ int main(int argc, char **argv)
back->special(backhandle, TS_EOF);
sending = FALSE; /* send nothing further after this */
} else {
back->send(backhandle, buf, ret);
if (local_tty)
from_tty(buf, ret);
else
back->send(backhandle, buf, ret);
}
}
}