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BSD 4 development
[unix-history] / usr / src / sys / dev / ttynew.c
/* ttynew.c 4.3 11/9/80 */
/*
* New version of tty driver, supported
* as NTTYDISC. Adapted from a tty.c written
* by J.E.Kulp of IIASA, Austria (jekulp@mc)
*/
#include "../h/param.h"
#include "../h/systm.h"
#include "../h/dir.h"
#include "../h/user.h"
#include "../h/tty.h"
#include "../h/proc.h"
#include "../h/mx.h"
#include "../h/inode.h"
#include "../h/file.h"
#include "../h/reg.h"
#include "../h/conf.h"
#include "../h/buf.h"
#include "../h/dk.h"
char partab[];
/*
* When running dz's using only SAE (silo alarm) on input
* it is necessary to call dzrint() at clock interrupt time.
* This is unsafe unless spl5()s in tty code are changed to
* spl6()s to block clock interrupts. Note that the dh driver
* currently in use works the same way as the dz, even though
* we could try to more intelligently manage its silo.
* Thus don't take this out if you have no dz's unless you
* change clock.c and dhtimer().
*/
#define spl5 spl6
/*
* Input mapping table-- if an entry is non-zero, when the
* corresponding character is typed preceded by "\" the escape
* sequence is replaced by the table value. Mostly used for
* upper-case only terminals.
*/
char maptab[]; /* see tty.c */
/*
* shorthand
*/
#define q1 tp->t_rawq
#define q2 tp->t_canq
#define q3 tp->t_outq
#define q4 tp->t_un.t_ctlq
#define OBUFSIZ 100
/*
* routine called on opens while tp->t_line == NTTYDISC
* establishes a process group for distribution of
* quits and interrupts from the tty.
* (actually, pp->p_pgrp can't be 0 when this routine
* is called since NTTYDISC is not the default discipline)
*/
ntyopen(dev, tp)
dev_t dev;
register struct tty *tp;
{
register struct proc *pp;
pp = u.u_procp;
tp->t_dev = dev;
if(pp->p_pgrp == 0) {
u.u_ttyp = tp;
u.u_ttyd = dev;
if (tp->t_pgrp == 0)
tp->t_pgrp = pp->p_pid;
pp->p_pgrp = tp->t_pgrp;
}
tp->t_state &= ~WOPEN;
tp->t_state |= ISOPEN;
if (tp->t_line != NTTYDISC)
wflushtty(tp);
}
/*
* clean tp on last close
*/
ntyclose(tp)
register struct tty *tp;
{
wflushtty(tp);
/* let ttyclose do the work if we are really closing */
}
/*
* block transfer input handler.
*/
ntyrend(tp, pb, pe)
register struct tty *tp;
register char *pb, *pe;
{
int tandem;
tandem = tp->t_flags&TANDEM;
if (tp->t_flags&RAW) {
(void) b_to_q(pb, pe-pb, &tp->t_rawq);
if (tp->t_chan)
(void) sdata(tp->t_chan);
else
wakeup((caddr_t)&tp->t_rawq);
} else {
tp->t_flags &= ~TANDEM;
while (pb < pe)
ntyinput(*pb++, tp);
tp->t_flags |= tandem;
}
if (tandem)
ttyblock(tp);
}
/*
* reinput pending characters after state switch
* call at spl5().
*/
ntypend(tp)
register struct tty *tp;
{
struct clist tq;
register c;
tp->t_local &= ~LPENDIN;
tp->t_lstate |= LSTYPEN;
tq = tp->t_rawq;
tp->t_rawq.c_cc = 0;
tp->t_rawq.c_cf = tp->t_rawq.c_cl = 0;
while ((c = getc(&tq)) >= 0)
ntyinput(c, tp);
tp->t_lstate &= ~LSTYPEN;
}
/*
* Place a character on raw TTY input queue, putting in delimiters
* and waking up top half as needed.
* Also echo if required.
* The arguments are the character and the appropriate
* tty structure.
*/
ntyinput(c, tp)
register c;
register struct tty *tp;
{
register int t_flags;
int i;
if (tp->t_local&LPENDIN)
ntypend(tp);
tk_nin++;
c &= 0377;
t_flags = tp->t_flags;
if (t_flags&TANDEM)
ttyblock(tp);
if ((t_flags&RAW)==0) {
if ((tp->t_lstate&LSTYPEN) == 0)
c &= 0177;
/* check for literal nexting very first */
if (tp->t_lstate&LSLNCH) {
c |= 0200;
tp->t_lstate &= ~LSLNCH;
}
if (c==tlun.t_lnextc) {
if (tp->t_flags&ECHO)
ntyout("^\b", tp);
tp->t_lstate |= LSLNCH;
/* check for output control functions */
} else if (c==tun.t_stopc) {
if ((tp->t_state&TTSTOP)==0) {
tp->t_state |= TTSTOP;
(*cdevsw[major(tp->t_dev)].d_stop)(tp);
return;
}
if (c!=tun.t_startc)
return;
} else if (c==tun.t_startc)
;
/* check for input interrupts (and flushed output) */
else if (c==tlun.t_flushc) {
if (tp->t_local & LFLUSHO)
tp->t_local &= ~LFLUSHO;
else {
flushtty(tp, FWRITE);
ntyecho(c, tp);
if (tp->t_rawq.c_cc+tp->t_canq.c_cc)
ntyretype(tp);
tp->t_local |= LFLUSHO;
}
ttstart(tp);
return;
} else if (c==tlun.t_suspc || c==tun.t_intrc ||
c==tun.t_quitc) {
flushtty(tp, c==tlun.t_suspc ? FREAD : FREAD|FWRITE);
ntyecho(c, tp);
c = c==tun.t_intrc ? SIGINT :
((c==tun.t_quitc) ? SIGQUIT : SIGTSTP);
if (tp->t_chan)
scontrol(tp->t_chan, M_SIG, c);
else
gsignal(tp->t_pgrp, c);
/* check for buffer editing functions - cooked mode */
} else if ((t_flags&CBREAK) == 0) {
if ((tp->t_lstate&LSQUOT) &&
(c==tp->t_erase||c==tp->t_kill)) {
ntyrub(unputc(&tp->t_rawq), tp);
c |= 0200;
}
if (c==tp->t_erase) {
if (tp->t_rawq.c_cc)
ntyrub(unputc(&tp->t_rawq), tp);
} else if (c==tp->t_kill) {
if (tp->t_local&LCRTKIL &&
tp->t_rawq.c_cc == tp->t_rocount) {
while (tp->t_rawq.c_cc)
ntyrub(unputc(&tp->t_rawq), tp);
} else {
ntyecho(c, tp);
ntyecho('\n', tp);
while (getc(&tp->t_rawq) > 0)
;
tp->t_rocount = 0;
}
tp->t_lstate = 0;
} else if (c==tlun.t_werasc) {
if (tp->t_rawq.c_cc == 0)
goto out;
do {
c = unputc(&tp->t_rawq);
if (c != ' ' && c != '\t')
goto erasenb;
ntyrub(c, tp);
} while (tp->t_rawq.c_cc);
goto out;
erasenb:
do {
ntyrub(c, tp);
if (tp->t_rawq.c_cc == 0)
goto out;
c = unputc(&tp->t_rawq);
} while (c != ' ' && c != '\t');
(void) putc(c, &tp->t_rawq);
} else if (c==tlun.t_rprntc) {
ntyretype(tp);
/* check for cooked mode input buffer overflow */
} else if (tp->t_rawq.c_cc + tp->t_canq.c_cc > TTYHOG) {
/* we should start a timeout that flushes the
buffer if it stays full - same in CBREAK */
if (tp->t_outq.c_cc < TTHIWAT(tp))
(void) ntyoutput(CTRL(g), tp);
/* put data char in q for user and wakeup if a break char */
} else if (putc(c, &tp->t_rawq) >= 0) {
if (!ntbreakc(c, tp)) {
if (tp->t_rocount++ == 0)
tp->t_rocol = tp->t_col;
} else {
tp->t_rocount = 0;
catq(&tp->t_rawq, &tp->t_canq);
if (tp->t_chan)
(void) sdata(tp->t_chan);
else
wakeup((caddr_t)&tp->t_rawq);
if (tp->t_local&LINTRUP)
gsignal(tp->t_pgrp, SIGTINT);
}
tp->t_lstate &= ~LSQUOT;
if (c == '\\')
tp->t_lstate |= LSQUOT;
if (tp->t_lstate&LSERASE) {
tp->t_lstate &= ~LSERASE;
(void) ntyoutput('/', tp);
}
i = tp->t_col;
ntyecho(c, tp);
if (c==tun.t_eofc && tp->t_flags&ECHO) {
i = MIN(2, tp->t_col - i);
while (i > 0) {
(void) ntyoutput('\b', tp);
i--;
}
}
}
/* CBREAK mode */
} else if (tp->t_rawq.c_cc > TTYHOG) {
if (tp->t_outq.c_cc < TTHIWAT(tp))
(void) ntyoutput(CTRL(g), tp);
} else if (putc(c, &tp->t_rawq) >= 0) {
if (tp->t_local&LINTRUP)
gsignal(tp->t_pgrp, SIGTINT);
if (tp->t_chan)
(void) sdata(tp->t_chan);
else
wakeup((caddr_t)&tp->t_rawq);
ntyecho(c, tp);
}
/* RAW mode */
} else if (tp->t_rawq.c_cc > TTYHOG)
flushtty(tp, FREAD|FWRITE);
else if (putc(c, &tp->t_rawq) >= 0) {
if (tp->t_local&LINTRUP)
gsignal(tp->t_pgrp, SIGTINT);
if (tp->t_chan)
(void) sdata(tp->t_chan);
else
wakeup((caddr_t)&tp->t_rawq);
}
out:
tp->t_state &= ~TTSTOP;
tp->t_local &= ~LFLUSHO;
ttstart(tp);
}
/*
* put character on TTY output queue, adding delays,
* expanding tabs, and handling the CR/NL bit.
* It is called both from the top half for output, and from
* interrupt level for echoing.
* The arguments are the character and the tty structure.
* Returns < 0 if putc succeeds, otherwise returns char to resend
* Must be recursive.
*/
ntyoutput(c, tp)
register c;
register struct tty *tp;
{
register char *colp;
register ctype;
if (tp->t_flags&RAW || tp->t_local&LLITOUT) {
if (tp->t_local&LFLUSHO)
return (-1);
if (putc(c, &tp->t_outq))
return(c);
tk_nout++;
return (-1);
}
/*
* Ignore EOT in normal mode to avoid hanging up
* certain terminals.
*/
c &= 0177;
if (c==CEOT && (tp->t_flags&CBREAK)==0)
return (-1);
/*
* Turn tabs to spaces as required
*/
if (c=='\t' && (tp->t_flags&TBDELAY)==XTABS) {
register int s;
c = 8 - (tp->t_col&7);
if ((tp->t_local&LFLUSHO) == 0) {
s = spl5(); /* don't interrupt tabs */
c -= b_to_q(" ", c, &tp->t_outq);
tk_nout += c;
splx(s);
}
tp->t_col += c;
return (c ? -1 : '\t');
}
tk_nout++;
/*
* for upper-case-only terminals,
* generate escapes.
*/
if (tp->t_flags&LCASE) {
colp = "({)}!|^~'`";
while(*colp++)
if(c == *colp++) {
if (ntyoutput('\\', tp) >= 0)
return (c);
c = colp[-2];
break;
}
if ('A'<=c && c<='Z') {
if (ntyoutput('\\', tp) >= 0)
return (c);
} else if ('a'<=c && c<='z')
c += 'A' - 'a';
}
/*
* turn <nl> to <cr><lf> if desired.
*/
if (c=='\n' && tp->t_flags&CRMOD)
if (ntyoutput('\r', tp) >= 0)
return (c);
if (c=='~' && tp->t_local&LTILDE)
c = '`';
if ((tp->t_local&LFLUSHO) == 0 && putc(c, &tp->t_outq))
return (c);
/*
* Calculate delays.
* The numbers here represent clock ticks
* and are not necessarily optimal for all terminals.
* The delays are indicated by characters above 0200.
* In raw mode there are no delays and the
* transmission path is 8 bits wide.
*/
colp = &tp->t_col;
ctype = partab[c];
c = 0;
switch (ctype&077) {
case ORDINARY:
(*colp)++;
case CONTROL:
break;
case BACKSPACE:
if (*colp)
(*colp)--;
break;
case NEWLINE:
ctype = (tp->t_flags >> 8) & 03;
if(ctype == 1) { /* tty 37 */
if (*colp)
c = max(((unsigned)*colp>>4) + 3, (unsigned)6);
} else
if(ctype == 2) { /* vt05 */
c = 6;
}
*colp = 0;
break;
case TAB:
ctype = (tp->t_flags >> 10) & 03;
if(ctype == 1) { /* tty 37 */
c = 1 - (*colp | ~07);
if(c < 5)
c = 0;
}
*colp |= 07;
(*colp)++;
break;
case VTAB:
if(tp->t_flags & VTDELAY) /* tty 37 */
c = 0177;
break;
case RETURN:
ctype = (tp->t_flags >> 12) & 03;
if(ctype == 1) { /* tn 300 */
c = 5;
} else if(ctype == 2) { /* ti 700 */
c = 10;
} else if(ctype == 3) { /* concept 100 */
int i;
if ((i = *colp) >= 0)
for (; i<9; i++)
(void) putc(0177, &tp->t_outq);
}
*colp = 0;
}
if(c && (tp->t_local&LFLUSHO) == 0)
(void) putc(c|0200, &tp->t_outq);
return (-1);
}
/*
* Called from device's read routine after it has
* calculated the tty-structure given as argument.
*/
ntread(tp)
register struct tty *tp;
{
register struct clist *qp;
register c, first;
if ((tp->t_state&CARR_ON)==0)
return(0);
loop:
(void) spl5();
if (tp->t_local&LPENDIN)
ntypend(tp);
(void) spl0();
while (tp == u.u_ttyp && u.u_procp->p_pgrp != tp->t_pgrp) {
if (u.u_signal[SIGTTIN] == SIG_IGN ||
u.u_signal[SIGTTIN] == SIG_HOLD ||
(u.u_procp->p_flag&SDETACH) ||
u.u_procp->p_flag&SVFORK)
return (0);
gsignal(u.u_procp->p_pgrp, SIGTTIN);
sleep((caddr_t)&lbolt, TTIPRI);
}
if (tp->t_flags&RAW) {
(void) spl5();
if (tp->t_rawq.c_cc <= 0) {
if ((tp->t_state&CARR_ON)==0 || tp->t_chan!=NULL) {
(void) spl0();
return (0);
}
if (tp->t_local&LINTRUP &&
u.u_signal[SIGTINT] != SIG_DFL) {
u.u_error = EIO;
(void) spl0();
return (0);
}
sleep((caddr_t)&tp->t_rawq, TTIPRI);
(void) spl0();
goto loop;
}
(void) spl0();
while (tp->t_rawq.c_cc && passc(getc(&tp->t_rawq))>=0)
;
return (0);
} else {
qp = tp->t_flags & CBREAK ? &tp->t_rawq : &tp->t_canq;
(void) spl5();
if (qp->c_cc <= 0) {
if ((tp->t_state&CARR_ON)==0 || tp->t_chan!=NULL) {
(void) spl0();
return (0);
}
if (tp->t_local&LINTRUP &&
u.u_signal[SIGTINT] != SIG_DFL) {
u.u_error = EIO;
(void) spl0();
return (0);
}
sleep((caddr_t)&tp->t_rawq, TTIPRI);
(void) spl0();
goto loop;
}
(void) spl0();
first = 1;
while ((c = getc(qp)) >= 0) {
if (tp->t_flags&CRMOD && c == '\r')
c = '\n';
if (tp->t_flags&LCASE && c <= 0177)
if (tp->t_lstate&LSBKSL) {
if (maptab[c])
c = maptab[c];
tp->t_lstate &= ~LSBKSL;
} else if (c >= 'A' && c <= 'Z')
c += 'a' - 'A';
else if (c == '\\') {
tp->t_lstate |= LSBKSL;
continue;
}
if (c == tlun.t_dsuspc) {
gsignal(tp->t_pgrp, SIGTSTP);
if (first) {
sleep((caddr_t)&lbolt, TTIPRI);
goto loop;
}
break;
}
if (c == tun.t_eofc && (tp->t_flags&CBREAK)==0)
break;
if (passc(c & 0177) < 0)
break;
if ((tp->t_flags&CBREAK)==0 && ntbreakc(c, tp))
break;
first = 0;
}
tp->t_lstate &= ~LSBKSL;
}
if (tp->t_state&TBLOCK && tp->t_rawq.c_cc < TTYHOG/5) {
if (putc(tun.t_startc, &tp->t_outq)==0) {
tp->t_state &= ~TBLOCK;
ttstart(tp);
}
tp->t_char = 0;
}
return (tp->t_rawq.c_cc + tp->t_canq.c_cc);
}
/*
* Called from the device's write routine after it has
* calculated the tty-structure given as argument.
*/
caddr_t
ntwrite(tp)
register struct tty *tp;
{
#ifdef VAX
/*
* THE POSITIONING OF CP, CC, AND CE ARE CRITICAL
* AND MUST NOT BE CHANGED WITHOUT PATCHING
* THE 'ASM' INLINES BELOW. WATCH OUT.
*/
#endif
register char *cp;
register int cc, ce;
register i;
char obuf[OBUFSIZ];
register c;
int hiwat = TTHIWAT(tp);
if ((tp->t_state&CARR_ON)==0)
return (NULL);
loop:
while (u.u_procp->p_pgrp != tp->t_pgrp && tp == u.u_ttyp &&
(tp->t_local&LTOSTOP) && (u.u_procp->p_flag&SVFORK)==0 &&
u.u_signal[SIGTTOU] != SIG_IGN &&
u.u_signal[SIGTTOU] != SIG_HOLD &&
(u.u_procp->p_flag&SDETACH)==0) {
gsignal(u.u_procp->p_pgrp, SIGTTOU);
sleep((caddr_t)&lbolt, TTIPRI);
}
while (u.u_count) {
cc = MIN(u.u_count, OBUFSIZ);
cp = obuf;
iomove(cp, (unsigned)cc, B_WRITE);
if (u.u_error)
break;
if (tp->t_outq.c_cc > hiwat)
goto ovhiwat;
if (tp->t_local&LFLUSHO)
continue;
if (tp->t_flags&LCASE || tp->t_local&LTILDE) {
while (cc--) {
c = *cp++;
tp->t_rocount = 0;
while((c = ntyoutput(c, tp)) >= 0) {
/* out of clists, wait a bit */
ttstart(tp);
sleep((caddr_t)&lbolt, TTOPRI);
tp->t_rocount = 0;
}
if (tp->t_outq.c_cc > hiwat)
goto ovhiwat;
}
continue;
}
while (cc) {
if (tp->t_flags&RAW || tp->t_local&LLITOUT)
ce = cc;
else {
#ifdef VAX
asm(" scanc r9,(r10),_partab,$077");
asm(" subl3 r0,r9,r8");
#else
ce=0;
while(((partab[*(unsigned char *)(cp+ce)]&077)==0)&&(ce<cc))
ce++;
#endif
if (ce==0) {
tp->t_rocount = 0;
if (ntyoutput(*cp, tp) >= 0) {
ttstart(tp);
sleep((caddr_t)&lbolt, TTOPRI);
continue;
}
cp++;
cc--;
if (tp->t_outq.c_cc > hiwat)
goto ovhiwat;
}
}
tp->t_rocount = 0;
i=b_to_q(cp,ce,&tp->t_outq);
ce-=i;
tk_nout+=ce;
tp->t_col+=ce;
cp+=ce;
cc-=ce;
if (i) {
ttstart(tp);
sleep((caddr_t)&lbolt, TTOPRI);
}
if (ce || tp->t_outq.c_cc > hiwat)
goto ovhiwat;
}
}
ttstart(tp);
return(NULL);
ovhiwat:
(void) spl5();
u.u_base -= cc;
u.u_offset -= cc;
u.u_count += cc;
if (tp->t_outq.c_cc <= hiwat) {
(void) spl0();
goto loop;
}
ttstart(tp);
tp->t_state |= ASLEEP;
if (tp->t_chan) {
(void) spl0();
return ((caddr_t)&tp->t_outq);
}
sleep((caddr_t)&tp->t_outq, TTOPRI);
(void) spl0();
goto loop;
}
/*
* Rubout one character from the rawq of tp
* as cleanly as possible.
*/
ntyrub(c, tp)
register c;
register struct tty *tp;
{
register char *cp;
register int savecol;
int s;
char *nextc();
if ((tp->t_flags&ECHO)==0)
return;
tp->t_local &= ~LFLUSHO;
c &= 0377;
if (tp->t_local&LCRTBS) {
if (tp->t_rocount == 0) {
/*
* Screwed by ttwrite; retype
*/
ntyretype(tp);
return;
}
if (c==('\t'|0200) || c==('\n'|0200))
ntyrubo(tp, 2);
else switch(partab[c&=0177] & 0177) {
case ORDINARY:
if (tp->t_flags&LCASE && c >= 'A' && c <= 'Z')
ntyrubo(tp, 2);
else
ntyrubo(tp, 1);
break;
case VTAB:
case BACKSPACE:
case CONTROL:
case RETURN:
if (tp->t_local & LCTLECH)
ntyrubo(tp, 2);
break;
case TAB:
if (tp->t_rocount < tp->t_rawq.c_cc) {
ntyretype(tp);
return;
}
s = spl5();
savecol = tp->t_col;
tp->t_lstate |= LSCNTTB;
tp->t_local |= LFLUSHO;
tp->t_col = tp->t_rocol;
for (cp = tp->t_rawq.c_cf; cp; cp = nextc(&tp->t_rawq, cp))
ntyecho(*cp, tp);
tp->t_local &= ~LFLUSHO;
tp->t_lstate &= ~LSCNTTB;
splx(s);
/*
* savecol will now be length of the tab
*/
savecol -= tp->t_col;
tp->t_col += savecol;
if (savecol > 8)
savecol = 8; /* overflow screw */
while (--savecol >= 0)
(void) ntyoutput('\b', tp);
break;
default:
panic("ttyrub");
}
} else if (tp->t_local&LPRTERA) {
if ((tp->t_lstate&LSERASE) == 0) {
(void) ntyoutput('\\', tp);
tp->t_lstate |= LSERASE;
}
ntyecho(c, tp);
} else
ntyecho(tp->t_erase, tp);
tp->t_rocount--;
}
/*
* Crt back over cnt chars perhaps
* erasing them.
*/
ntyrubo(tp, cnt)
register struct tty *tp;
int cnt;
{
while (--cnt >= 0)
ntyout(tp->t_local&LCRTERA ? "\b \b" : "\b", tp);
}
/*
* Reprint the rawq line.
* We assume c_cc has already been checked.
*/
ntyretype(tp)
register struct tty *tp;
{
register char *cp;
char *nextc();
int s;
if (tlun.t_rprntc != 0377)
ntyecho(tlun.t_rprntc, tp);
(void) ntyoutput('\n', tp);
s = spl5();
for (cp = tp->t_canq.c_cf; cp; cp = nextc(&tp->t_canq, cp))
ntyecho(*cp, tp);
for (cp = tp->t_rawq.c_cf; cp; cp = nextc(&tp->t_rawq, cp))
ntyecho(*cp, tp);
tp->t_lstate &= ~LSERASE;
splx(s);
tp->t_rocount = tp->t_rawq.c_cc;
tp->t_rocol = 0;
}
/*
* Echo a typed character to the terminal
*/
ntyecho(c, tp)
register c;
register struct tty *tp;
{
if ((tp->t_lstate & LSCNTTB) == 0)
tp->t_local &= ~LFLUSHO;
c &= 0377;
if (tp->t_flags&ECHO) {
if (c == '\r' && tp->t_flags&CRMOD)
c = '\n';
if (tp->t_local&LCTLECH) {
if ((c&0177) <= 037 && c!='\t' && c!='\n' || (c&0177)==0177) {
(void) ntyoutput('^', tp);
c &= 0177;
if (c == 0177)
c = '?';
else if (tp->t_flags&LCASE)
c += 'a' - 1;
else
c += 'A' - 1;
}
}
(void) ntyoutput(c & 0177, tp);
}
}
/*
* Is c a break char for tp?
*/
ntbreakc(c, tp)
register c;
register struct tty *tp;
{
return (c == '\n' || c == tun.t_eofc || c == tun.t_brkc ||
c == '\r' && (tp->t_flags&CRMOD));
}
/*
* send string cp to tp
*/
ntyout(cp, tp)
register char *cp;
register struct tty *tp;
{
register char c;
while (c = *cp++)
(void) ntyoutput(c, tp);
}
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.