19
20#include <sys/param.h>
21#include <sys/systm.h>
22#include <sys/fcntl.h>
23#include <sys/filio.h>
24#include <sys/malloc.h>
25#include <sys/tty.h>
26#include <sys/conf.h>
27#include <sys/poll.h>
28#include <sys/kernel.h>
29#include <sys/module.h>
30#include <sys/queue.h>
31#include <sys/snoop.h>
32#include <sys/uio.h>
33
34static l_close_t snplclose;
35static l_write_t snplwrite;
36static d_open_t snpopen;
37static d_close_t snpclose;
38static d_read_t snpread;
39static d_write_t snpwrite;
40static d_ioctl_t snpioctl;
41static d_poll_t snppoll;
42
43static struct cdevsw snp_cdevsw = {
44 .d_version = D_VERSION,
45 .d_flags = D_PSEUDO | D_NEEDGIANT,
46 .d_open = snpopen,
47 .d_close = snpclose,
48 .d_read = snpread,
49 .d_write = snpwrite,
50 .d_ioctl = snpioctl,
51 .d_poll = snppoll,
52 .d_name = "snp",
53};
54
55static struct linesw snpdisc = {
56 .l_open = tty_open,
57 .l_close = snplclose,
58 .l_read = ttread,
59 .l_write = snplwrite,
60 .l_ioctl = l_nullioctl,
61 .l_rint = ttyinput,
62 .l_start = ttstart,
63 .l_modem = ttymodem
64};
65
66/*
67 * This is the main snoop per-device structure.
68 */
69struct snoop {
70 LIST_ENTRY(snoop) snp_list; /* List glue. */
71 int snp_unit; /* Device number. */
72 struct cdev *snp_target; /* Target tty device. */
73 struct tty *snp_tty; /* Target tty pointer. */
74 u_long snp_len; /* Possible length. */
75 u_long snp_base; /* Data base. */
76 u_long snp_blen; /* Used length. */
77 caddr_t snp_buf; /* Allocation pointer. */
78 int snp_flags; /* Flags. */
79 struct selinfo snp_sel; /* Select info. */
80 int snp_olddisc; /* Old line discipline. */
81};
82
83/*
84 * Possible flags.
85 */
86#define SNOOP_ASYNC 0x0002
87#define SNOOP_OPEN 0x0004
88#define SNOOP_RWAIT 0x0008
89#define SNOOP_OFLOW 0x0010
90#define SNOOP_DOWN 0x0020
91
92/*
93 * Other constants.
94 */
95#define SNOOP_MINLEN (4*1024) /* This should be power of 2.
96 * 4K tested to be the minimum
97 * for which on normal tty
98 * usage there is no need to
99 * allocate more.
100 */
101#define SNOOP_MAXLEN (64*1024) /* This one also,64K enough
102 * If we grow more,something
103 * really bad in this world..
104 */
105
106static MALLOC_DEFINE(M_SNP, "snp", "Snoop device data");
107/*
108 * The number of the "snoop" line discipline. This gets determined at
109 * module load time.
110 */
111static int snooplinedisc;
112
113static LIST_HEAD(, snoop) snp_sclist = LIST_HEAD_INITIALIZER(&snp_sclist);
114static struct clonedevs *snpclones;
115
116static struct tty *snpdevtotty(struct cdev *dev);
117static void snp_clone(void *arg, char *name,
118 int namelen, struct cdev **dev);
119static int snp_detach(struct snoop *snp);
120static int snp_down(struct snoop *snp);
121static int snp_in(struct snoop *snp, char *buf, int n);
122static int snp_modevent(module_t mod, int what, void *arg);
123static struct snoop *ttytosnp(struct tty *);
124
125static struct snoop *
126ttytosnp(struct tty *tp)
127{
128 struct snoop *snp;
129
130 LIST_FOREACH(snp, &snp_sclist, snp_list) {
131 if (snp->snp_tty == tp)
132 return (snp);
133 }
134 return (NULL);
135}
136
137static int
138snplclose(tp, flag)
139 struct tty *tp;
140 int flag;
141{
142 struct snoop *snp;
143 int error;
144
145 snp = ttytosnp(tp);
146 error = snp_down(snp);
147 if (error != 0)
148 return (error);
149 error = ttylclose(tp, flag);
150 return (error);
151}
152
153static int
154snplwrite(tp, uio, flag)
155 struct tty *tp;
156 struct uio *uio;
157 int flag;
158{
159 struct iovec iov;
160 struct uio uio2;
161 struct snoop *snp;
162 int error, ilen;
163 char *ibuf;
164
165 error = 0;
166 ibuf = NULL;
167 snp = ttytosnp(tp);
168 while (uio->uio_resid > 0) {
169 ilen = imin(512, uio->uio_resid);
170 ibuf = malloc(ilen, M_SNP, M_WAITOK);
171 error = uiomove(ibuf, ilen, uio);
172 if (error != 0)
173 break;
174 snp_in(snp, ibuf, ilen);
175 /* Hackish, but probably the least of all evils. */
176 iov.iov_base = ibuf;
177 iov.iov_len = ilen;
178 uio2.uio_iov = &iov;
179 uio2.uio_iovcnt = 1;
180 uio2.uio_offset = 0;
181 uio2.uio_resid = ilen;
182 uio2.uio_segflg = UIO_SYSSPACE;
183 uio2.uio_rw = UIO_WRITE;
184 uio2.uio_td = uio->uio_td;
185 error = ttwrite(tp, &uio2, flag);
186 if (error != 0)
187 break;
188 free(ibuf, M_SNP);
189 ibuf = NULL;
190 }
191 if (ibuf != NULL)
192 free(ibuf, M_SNP);
193 return (error);
194}
195
196static struct tty *
197snpdevtotty(dev)
198 struct cdev *dev;
199{
200 struct cdevsw *cdp;
201 struct tty *tp;
202
203 cdp = dev_refthread(dev);
204 if (cdp == NULL)
205 return (NULL);
206 if (!(cdp->d_flags & D_TTY))
207 tp = NULL;
208 else
209 tp = dev->si_tty;
210 dev_relthread(dev);
211 return (tp);
212}
213
214#define SNP_INPUT_BUF 5 /* This is even too much, the maximal
215 * interactive mode write is 3 bytes
216 * length for function keys...
217 */
218
219static int
220snpwrite(dev, uio, flag)
221 struct cdev *dev;
222 struct uio *uio;
223 int flag;
224{
225 struct snoop *snp;
226 struct tty *tp;
227 int error, i, len;
228 unsigned char c[SNP_INPUT_BUF];
229
230 snp = dev->si_drv1;
231 tp = snp->snp_tty;
232 if (tp == NULL)
233 return (EIO);
234 if ((tp->t_state & TS_SNOOP) && tp->t_line == snooplinedisc)
235 goto tty_input;
236
237 printf("snp%d: attempt to write to bad tty\n", snp->snp_unit);
238 return (EIO);
239
240tty_input:
241 if (!(tp->t_state & TS_ISOPEN))
242 return (EIO);
243
244 while (uio->uio_resid > 0) {
245 len = imin(uio->uio_resid, SNP_INPUT_BUF);
246 if ((error = uiomove(c, len, uio)) != 0)
247 return (error);
248 for (i=0; i < len; i++) {
249 if (ttyinput(c[i], tp))
250 return (EIO);
251 }
252 }
253 return (0);
254}
255
256
257static int
258snpread(dev, uio, flag)
259 struct cdev *dev;
260 struct uio *uio;
261 int flag;
262{
263 struct snoop *snp;
264 int error, len, n, nblen, s;
265 caddr_t from;
266 char *nbuf;
267
268 snp = dev->si_drv1;
269 KASSERT(snp->snp_len + snp->snp_base <= snp->snp_blen,
270 ("snoop buffer error"));
271
272 if (snp->snp_tty == NULL)
273 return (EIO);
274
275 snp->snp_flags &= ~SNOOP_RWAIT;
276
277 do {
278 if (snp->snp_len == 0) {
279 if (flag & O_NONBLOCK)
280 return (EWOULDBLOCK);
281 snp->snp_flags |= SNOOP_RWAIT;
282 error = tsleep(snp, (PZERO + 1) | PCATCH,
283 "snprd", 0);
284 if (error != 0)
285 return (error);
286 }
287 } while (snp->snp_len == 0);
288
289 n = snp->snp_len;
290
291 error = 0;
292 while (snp->snp_len > 0 && uio->uio_resid > 0 && error == 0) {
293 len = min((unsigned)uio->uio_resid, snp->snp_len);
294 from = (caddr_t)(snp->snp_buf + snp->snp_base);
295 if (len == 0)
296 break;
297
298 error = uiomove(from, len, uio);
299 snp->snp_base += len;
300 snp->snp_len -= len;
301 }
302 if ((snp->snp_flags & SNOOP_OFLOW) && (n < snp->snp_len)) {
303 snp->snp_flags &= ~SNOOP_OFLOW;
304 }
305 s = spltty();
306 nblen = snp->snp_blen;
307 if (((nblen / 2) >= SNOOP_MINLEN) && (nblen / 2) >= snp->snp_len) {
308 while (nblen / 2 >= snp->snp_len && nblen / 2 >= SNOOP_MINLEN)
309 nblen = nblen / 2;
310 if ((nbuf = malloc(nblen, M_SNP, M_NOWAIT)) != NULL) {
311 bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
312 free(snp->snp_buf, M_SNP);
313 snp->snp_buf = nbuf;
314 snp->snp_blen = nblen;
315 snp->snp_base = 0;
316 }
317 }
318 splx(s);
319
320 return (error);
321}
322
323static int
324snp_in(snp, buf, n)
325 struct snoop *snp;
326 char *buf;
327 int n;
328{
329 int s_free, s_tail;
330 int s, len, nblen;
331 caddr_t from, to;
332 char *nbuf;
333
334 KASSERT(n >= 0, ("negative snoop char count"));
335
336 if (n == 0)
337 return (0);
338
339 if (snp->snp_flags & SNOOP_DOWN) {
340 printf("snp%d: more data to down interface\n", snp->snp_unit);
341 return (0);
342 }
343
344 if (snp->snp_flags & SNOOP_OFLOW) {
345 printf("snp%d: buffer overflow\n", snp->snp_unit);
346 /*
347 * On overflow we just repeat the standart close
348 * procedure...yes , this is waste of space but.. Then next
349 * read from device will fail if one would recall he is
350 * snooping and retry...
351 */
352
353 return (snp_down(snp));
354 }
355 s_tail = snp->snp_blen - (snp->snp_len + snp->snp_base);
356 s_free = snp->snp_blen - snp->snp_len;
357
358
359 if (n > s_free) {
360 s = spltty();
361 nblen = snp->snp_blen;
362 while ((n > s_free) && ((nblen * 2) <= SNOOP_MAXLEN)) {
363 nblen = snp->snp_blen * 2;
364 s_free = nblen - (snp->snp_len + snp->snp_base);
365 }
366 if ((n <= s_free) && (nbuf = malloc(nblen, M_SNP, M_NOWAIT))) {
367 bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
368 free(snp->snp_buf, M_SNP);
369 snp->snp_buf = nbuf;
370 snp->snp_blen = nblen;
371 snp->snp_base = 0;
372 } else {
373 snp->snp_flags |= SNOOP_OFLOW;
374 if (snp->snp_flags & SNOOP_RWAIT) {
375 snp->snp_flags &= ~SNOOP_RWAIT;
376 wakeup(snp);
377 }
378 splx(s);
379 return (0);
380 }
381 splx(s);
382 }
383 if (n > s_tail) {
384 from = (caddr_t)(snp->snp_buf + snp->snp_base);
385 to = (caddr_t)(snp->snp_buf);
386 len = snp->snp_len;
387 bcopy(from, to, len);
388 snp->snp_base = 0;
389 }
390 to = (caddr_t)(snp->snp_buf + snp->snp_base + snp->snp_len);
391 bcopy(buf, to, n);
392 snp->snp_len += n;
393
394 if (snp->snp_flags & SNOOP_RWAIT) {
395 snp->snp_flags &= ~SNOOP_RWAIT;
396 wakeup(snp);
397 }
398 selwakeuppri(&snp->snp_sel, PZERO + 1);
399
400 return (n);
401}
402
403static int
404snpopen(dev, flag, mode, td)
405 struct cdev *dev;
406 int flag, mode;
407 struct thread *td;
408{
409 struct snoop *snp;
410
411 if (dev->si_drv1 == NULL) {
412 dev->si_flags &= ~SI_CHEAPCLONE;
413 dev->si_drv1 = snp = malloc(sizeof(*snp), M_SNP,
414 M_WAITOK | M_ZERO);
415 snp->snp_unit = dev2unit(dev);
416 } else
417 return (EBUSY);
418
419 /*
420 * We intentionally do not OR flags with SNOOP_OPEN, but set them so
421 * all previous settings (especially SNOOP_OFLOW) will be cleared.
422 */
423 snp->snp_flags = SNOOP_OPEN;
424
425 snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
426 snp->snp_blen = SNOOP_MINLEN;
427 snp->snp_base = 0;
428 snp->snp_len = 0;
429
430 /*
431 * snp_tty == NULL is for inactive snoop devices.
432 */
433 snp->snp_tty = NULL;
434 snp->snp_target = NULL;
435
436 LIST_INSERT_HEAD(&snp_sclist, snp, snp_list);
437 return (0);
438}
439
440
441static int
442snp_detach(snp)
443 struct snoop *snp;
444{
445 struct tty *tp;
446
447 snp->snp_base = 0;
448 snp->snp_len = 0;
449
450 /*
451 * If line disc. changed we do not touch this pointer, SLIP/PPP will
452 * change it anyway.
453 */
454 tp = snp->snp_tty;
455 if (tp == NULL)
456 goto detach_notty;
457
458 if ((tp->t_state & TS_SNOOP) && tp->t_line == snooplinedisc) {
459 tp->t_state &= ~TS_SNOOP;
460 tp->t_line = snp->snp_olddisc;
461 } else
462 printf("snp%d: bad attached tty data\n", snp->snp_unit);
463
464 snp->snp_tty = NULL;
465 snp->snp_target = NULL;
466
467detach_notty:
468 selwakeuppri(&snp->snp_sel, PZERO + 1);
469 if ((snp->snp_flags & SNOOP_OPEN) == 0)
470 free(snp, M_SNP);
471
472 return (0);
473}
474
475static int
476snpclose(dev, flags, fmt, td)
477 struct cdev *dev;
478 int flags;
479 int fmt;
480 struct thread *td;
481{
482 struct snoop *snp;
483
484 snp = dev->si_drv1;
485 snp->snp_blen = 0;
486 LIST_REMOVE(snp, snp_list);
487 free(snp->snp_buf, M_SNP);
488 snp->snp_flags &= ~SNOOP_OPEN;
489 dev->si_drv1 = NULL;
490 destroy_dev(dev);
491
492 return (snp_detach(snp));
493}
494
495static int
496snp_down(snp)
497 struct snoop *snp;
498{
499
500 if (snp->snp_blen != SNOOP_MINLEN) {
501 free(snp->snp_buf, M_SNP);
502 snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
503 snp->snp_blen = SNOOP_MINLEN;
504 }
505 snp->snp_flags |= SNOOP_DOWN;
506
507 return (snp_detach(snp));
508}
509
510static int
511snpioctl(dev, cmd, data, flags, td)
512 struct cdev *dev;
513 u_long cmd;
514 caddr_t data;
515 int flags;
516 struct thread *td;
517{
518 struct snoop *snp;
519 struct tty *tp, *tpo;
520 struct cdev *tdev;
521 int s;
522
523 snp = dev->si_drv1;
524 switch (cmd) {
525 case SNPSTTY:
526#if 0
527 tdev = findcdev(*((dev_t *)data));
528#else
529 tdev = NULL;
530#endif
531 if (tdev == NULL)
532 return (snp_down(snp));
533
534 tp = snpdevtotty(tdev);
535 if (!tp)
536 return (EINVAL);
537 if (tp->t_state & TS_SNOOP)
538 return (EBUSY);
539
540 s = spltty();
541
542 if (snp->snp_target == NULL) {
543 tpo = snp->snp_tty;
544 if (tpo)
545 tpo->t_state &= ~TS_SNOOP;
546 }
547
548 tp->t_state |= TS_SNOOP;
549 snp->snp_olddisc = tp->t_line;
550 tp->t_line = snooplinedisc;
551 snp->snp_tty = tp;
552 snp->snp_target = tdev;
553
554 /*
555 * Clean overflow and down flags -
556 * we'll have a chance to get them in the future :)))
557 */
558 snp->snp_flags &= ~SNOOP_OFLOW;
559 snp->snp_flags &= ~SNOOP_DOWN;
560 splx(s);
561 break;
562
563 case SNPGTTY:
564 /*
565 * We keep snp_target field specially to make
566 * SNPGTTY happy, else we can't know what is device
567 * major/minor for tty.
568 */
569 *((dev_t *)data) = dev2udev(snp->snp_target);
570 break;
571
572 case FIONBIO:
573 break;
574
575 case FIOASYNC:
576 if (*(int *)data)
577 snp->snp_flags |= SNOOP_ASYNC;
578 else
579 snp->snp_flags &= ~SNOOP_ASYNC;
580 break;
581
582 case FIONREAD:
583 s = spltty();
584 if (snp->snp_tty != NULL)
585 *(int *)data = snp->snp_len;
586 else
587 if (snp->snp_flags & SNOOP_DOWN) {
588 if (snp->snp_flags & SNOOP_OFLOW)
589 *(int *)data = SNP_OFLOW;
590 else
591 *(int *)data = SNP_TTYCLOSE;
592 } else {
593 *(int *)data = SNP_DETACH;
594 }
595 splx(s);
596 break;
597
598 default:
599 return (ENOTTY);
600 }
601 return (0);
602}
603
604static int
605snppoll(dev, events, td)
606 struct cdev *dev;
607 int events;
608 struct thread *td;
609{
610 struct snoop *snp;
611 int revents;
612
613 snp = dev->si_drv1;
614 revents = 0;
615 /*
616 * If snoop is down, we don't want to poll() forever so we return 1.
617 * Caller should see if we down via FIONREAD ioctl(). The last should
618 * return -1 to indicate down state.
619 */
620 if (events & (POLLIN | POLLRDNORM)) {
621 if (snp->snp_flags & SNOOP_DOWN || snp->snp_len > 0)
622 revents |= events & (POLLIN | POLLRDNORM);
623 else
624 selrecord(td, &snp->snp_sel);
625 }
626 return (revents);
627}
628
629static void
630snp_clone(arg, name, namelen, dev)
631 void *arg;
632 char *name;
633 int namelen;
634 struct cdev **dev;
635{
636 int u, i;
637
638 if (*dev != NULL)
639 return;
640 if (dev_stdclone(name, NULL, "snp", &u) != 1)
641 return;
642 i = clone_create(&snpclones, &snp_cdevsw, &u, dev, 0);
643 if (i)
644 *dev = make_dev(&snp_cdevsw, unit2minor(u),
645 UID_ROOT, GID_WHEEL, 0600, "snp%d", u);
| 19
20#include <sys/param.h>
21#include <sys/systm.h>
22#include <sys/fcntl.h>
23#include <sys/filio.h>
24#include <sys/malloc.h>
25#include <sys/tty.h>
26#include <sys/conf.h>
27#include <sys/poll.h>
28#include <sys/kernel.h>
29#include <sys/module.h>
30#include <sys/queue.h>
31#include <sys/snoop.h>
32#include <sys/uio.h>
33
34static l_close_t snplclose;
35static l_write_t snplwrite;
36static d_open_t snpopen;
37static d_close_t snpclose;
38static d_read_t snpread;
39static d_write_t snpwrite;
40static d_ioctl_t snpioctl;
41static d_poll_t snppoll;
42
43static struct cdevsw snp_cdevsw = {
44 .d_version = D_VERSION,
45 .d_flags = D_PSEUDO | D_NEEDGIANT,
46 .d_open = snpopen,
47 .d_close = snpclose,
48 .d_read = snpread,
49 .d_write = snpwrite,
50 .d_ioctl = snpioctl,
51 .d_poll = snppoll,
52 .d_name = "snp",
53};
54
55static struct linesw snpdisc = {
56 .l_open = tty_open,
57 .l_close = snplclose,
58 .l_read = ttread,
59 .l_write = snplwrite,
60 .l_ioctl = l_nullioctl,
61 .l_rint = ttyinput,
62 .l_start = ttstart,
63 .l_modem = ttymodem
64};
65
66/*
67 * This is the main snoop per-device structure.
68 */
69struct snoop {
70 LIST_ENTRY(snoop) snp_list; /* List glue. */
71 int snp_unit; /* Device number. */
72 struct cdev *snp_target; /* Target tty device. */
73 struct tty *snp_tty; /* Target tty pointer. */
74 u_long snp_len; /* Possible length. */
75 u_long snp_base; /* Data base. */
76 u_long snp_blen; /* Used length. */
77 caddr_t snp_buf; /* Allocation pointer. */
78 int snp_flags; /* Flags. */
79 struct selinfo snp_sel; /* Select info. */
80 int snp_olddisc; /* Old line discipline. */
81};
82
83/*
84 * Possible flags.
85 */
86#define SNOOP_ASYNC 0x0002
87#define SNOOP_OPEN 0x0004
88#define SNOOP_RWAIT 0x0008
89#define SNOOP_OFLOW 0x0010
90#define SNOOP_DOWN 0x0020
91
92/*
93 * Other constants.
94 */
95#define SNOOP_MINLEN (4*1024) /* This should be power of 2.
96 * 4K tested to be the minimum
97 * for which on normal tty
98 * usage there is no need to
99 * allocate more.
100 */
101#define SNOOP_MAXLEN (64*1024) /* This one also,64K enough
102 * If we grow more,something
103 * really bad in this world..
104 */
105
106static MALLOC_DEFINE(M_SNP, "snp", "Snoop device data");
107/*
108 * The number of the "snoop" line discipline. This gets determined at
109 * module load time.
110 */
111static int snooplinedisc;
112
113static LIST_HEAD(, snoop) snp_sclist = LIST_HEAD_INITIALIZER(&snp_sclist);
114static struct clonedevs *snpclones;
115
116static struct tty *snpdevtotty(struct cdev *dev);
117static void snp_clone(void *arg, char *name,
118 int namelen, struct cdev **dev);
119static int snp_detach(struct snoop *snp);
120static int snp_down(struct snoop *snp);
121static int snp_in(struct snoop *snp, char *buf, int n);
122static int snp_modevent(module_t mod, int what, void *arg);
123static struct snoop *ttytosnp(struct tty *);
124
125static struct snoop *
126ttytosnp(struct tty *tp)
127{
128 struct snoop *snp;
129
130 LIST_FOREACH(snp, &snp_sclist, snp_list) {
131 if (snp->snp_tty == tp)
132 return (snp);
133 }
134 return (NULL);
135}
136
137static int
138snplclose(tp, flag)
139 struct tty *tp;
140 int flag;
141{
142 struct snoop *snp;
143 int error;
144
145 snp = ttytosnp(tp);
146 error = snp_down(snp);
147 if (error != 0)
148 return (error);
149 error = ttylclose(tp, flag);
150 return (error);
151}
152
153static int
154snplwrite(tp, uio, flag)
155 struct tty *tp;
156 struct uio *uio;
157 int flag;
158{
159 struct iovec iov;
160 struct uio uio2;
161 struct snoop *snp;
162 int error, ilen;
163 char *ibuf;
164
165 error = 0;
166 ibuf = NULL;
167 snp = ttytosnp(tp);
168 while (uio->uio_resid > 0) {
169 ilen = imin(512, uio->uio_resid);
170 ibuf = malloc(ilen, M_SNP, M_WAITOK);
171 error = uiomove(ibuf, ilen, uio);
172 if (error != 0)
173 break;
174 snp_in(snp, ibuf, ilen);
175 /* Hackish, but probably the least of all evils. */
176 iov.iov_base = ibuf;
177 iov.iov_len = ilen;
178 uio2.uio_iov = &iov;
179 uio2.uio_iovcnt = 1;
180 uio2.uio_offset = 0;
181 uio2.uio_resid = ilen;
182 uio2.uio_segflg = UIO_SYSSPACE;
183 uio2.uio_rw = UIO_WRITE;
184 uio2.uio_td = uio->uio_td;
185 error = ttwrite(tp, &uio2, flag);
186 if (error != 0)
187 break;
188 free(ibuf, M_SNP);
189 ibuf = NULL;
190 }
191 if (ibuf != NULL)
192 free(ibuf, M_SNP);
193 return (error);
194}
195
196static struct tty *
197snpdevtotty(dev)
198 struct cdev *dev;
199{
200 struct cdevsw *cdp;
201 struct tty *tp;
202
203 cdp = dev_refthread(dev);
204 if (cdp == NULL)
205 return (NULL);
206 if (!(cdp->d_flags & D_TTY))
207 tp = NULL;
208 else
209 tp = dev->si_tty;
210 dev_relthread(dev);
211 return (tp);
212}
213
214#define SNP_INPUT_BUF 5 /* This is even too much, the maximal
215 * interactive mode write is 3 bytes
216 * length for function keys...
217 */
218
219static int
220snpwrite(dev, uio, flag)
221 struct cdev *dev;
222 struct uio *uio;
223 int flag;
224{
225 struct snoop *snp;
226 struct tty *tp;
227 int error, i, len;
228 unsigned char c[SNP_INPUT_BUF];
229
230 snp = dev->si_drv1;
231 tp = snp->snp_tty;
232 if (tp == NULL)
233 return (EIO);
234 if ((tp->t_state & TS_SNOOP) && tp->t_line == snooplinedisc)
235 goto tty_input;
236
237 printf("snp%d: attempt to write to bad tty\n", snp->snp_unit);
238 return (EIO);
239
240tty_input:
241 if (!(tp->t_state & TS_ISOPEN))
242 return (EIO);
243
244 while (uio->uio_resid > 0) {
245 len = imin(uio->uio_resid, SNP_INPUT_BUF);
246 if ((error = uiomove(c, len, uio)) != 0)
247 return (error);
248 for (i=0; i < len; i++) {
249 if (ttyinput(c[i], tp))
250 return (EIO);
251 }
252 }
253 return (0);
254}
255
256
257static int
258snpread(dev, uio, flag)
259 struct cdev *dev;
260 struct uio *uio;
261 int flag;
262{
263 struct snoop *snp;
264 int error, len, n, nblen, s;
265 caddr_t from;
266 char *nbuf;
267
268 snp = dev->si_drv1;
269 KASSERT(snp->snp_len + snp->snp_base <= snp->snp_blen,
270 ("snoop buffer error"));
271
272 if (snp->snp_tty == NULL)
273 return (EIO);
274
275 snp->snp_flags &= ~SNOOP_RWAIT;
276
277 do {
278 if (snp->snp_len == 0) {
279 if (flag & O_NONBLOCK)
280 return (EWOULDBLOCK);
281 snp->snp_flags |= SNOOP_RWAIT;
282 error = tsleep(snp, (PZERO + 1) | PCATCH,
283 "snprd", 0);
284 if (error != 0)
285 return (error);
286 }
287 } while (snp->snp_len == 0);
288
289 n = snp->snp_len;
290
291 error = 0;
292 while (snp->snp_len > 0 && uio->uio_resid > 0 && error == 0) {
293 len = min((unsigned)uio->uio_resid, snp->snp_len);
294 from = (caddr_t)(snp->snp_buf + snp->snp_base);
295 if (len == 0)
296 break;
297
298 error = uiomove(from, len, uio);
299 snp->snp_base += len;
300 snp->snp_len -= len;
301 }
302 if ((snp->snp_flags & SNOOP_OFLOW) && (n < snp->snp_len)) {
303 snp->snp_flags &= ~SNOOP_OFLOW;
304 }
305 s = spltty();
306 nblen = snp->snp_blen;
307 if (((nblen / 2) >= SNOOP_MINLEN) && (nblen / 2) >= snp->snp_len) {
308 while (nblen / 2 >= snp->snp_len && nblen / 2 >= SNOOP_MINLEN)
309 nblen = nblen / 2;
310 if ((nbuf = malloc(nblen, M_SNP, M_NOWAIT)) != NULL) {
311 bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
312 free(snp->snp_buf, M_SNP);
313 snp->snp_buf = nbuf;
314 snp->snp_blen = nblen;
315 snp->snp_base = 0;
316 }
317 }
318 splx(s);
319
320 return (error);
321}
322
323static int
324snp_in(snp, buf, n)
325 struct snoop *snp;
326 char *buf;
327 int n;
328{
329 int s_free, s_tail;
330 int s, len, nblen;
331 caddr_t from, to;
332 char *nbuf;
333
334 KASSERT(n >= 0, ("negative snoop char count"));
335
336 if (n == 0)
337 return (0);
338
339 if (snp->snp_flags & SNOOP_DOWN) {
340 printf("snp%d: more data to down interface\n", snp->snp_unit);
341 return (0);
342 }
343
344 if (snp->snp_flags & SNOOP_OFLOW) {
345 printf("snp%d: buffer overflow\n", snp->snp_unit);
346 /*
347 * On overflow we just repeat the standart close
348 * procedure...yes , this is waste of space but.. Then next
349 * read from device will fail if one would recall he is
350 * snooping and retry...
351 */
352
353 return (snp_down(snp));
354 }
355 s_tail = snp->snp_blen - (snp->snp_len + snp->snp_base);
356 s_free = snp->snp_blen - snp->snp_len;
357
358
359 if (n > s_free) {
360 s = spltty();
361 nblen = snp->snp_blen;
362 while ((n > s_free) && ((nblen * 2) <= SNOOP_MAXLEN)) {
363 nblen = snp->snp_blen * 2;
364 s_free = nblen - (snp->snp_len + snp->snp_base);
365 }
366 if ((n <= s_free) && (nbuf = malloc(nblen, M_SNP, M_NOWAIT))) {
367 bcopy(snp->snp_buf + snp->snp_base, nbuf, snp->snp_len);
368 free(snp->snp_buf, M_SNP);
369 snp->snp_buf = nbuf;
370 snp->snp_blen = nblen;
371 snp->snp_base = 0;
372 } else {
373 snp->snp_flags |= SNOOP_OFLOW;
374 if (snp->snp_flags & SNOOP_RWAIT) {
375 snp->snp_flags &= ~SNOOP_RWAIT;
376 wakeup(snp);
377 }
378 splx(s);
379 return (0);
380 }
381 splx(s);
382 }
383 if (n > s_tail) {
384 from = (caddr_t)(snp->snp_buf + snp->snp_base);
385 to = (caddr_t)(snp->snp_buf);
386 len = snp->snp_len;
387 bcopy(from, to, len);
388 snp->snp_base = 0;
389 }
390 to = (caddr_t)(snp->snp_buf + snp->snp_base + snp->snp_len);
391 bcopy(buf, to, n);
392 snp->snp_len += n;
393
394 if (snp->snp_flags & SNOOP_RWAIT) {
395 snp->snp_flags &= ~SNOOP_RWAIT;
396 wakeup(snp);
397 }
398 selwakeuppri(&snp->snp_sel, PZERO + 1);
399
400 return (n);
401}
402
403static int
404snpopen(dev, flag, mode, td)
405 struct cdev *dev;
406 int flag, mode;
407 struct thread *td;
408{
409 struct snoop *snp;
410
411 if (dev->si_drv1 == NULL) {
412 dev->si_flags &= ~SI_CHEAPCLONE;
413 dev->si_drv1 = snp = malloc(sizeof(*snp), M_SNP,
414 M_WAITOK | M_ZERO);
415 snp->snp_unit = dev2unit(dev);
416 } else
417 return (EBUSY);
418
419 /*
420 * We intentionally do not OR flags with SNOOP_OPEN, but set them so
421 * all previous settings (especially SNOOP_OFLOW) will be cleared.
422 */
423 snp->snp_flags = SNOOP_OPEN;
424
425 snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
426 snp->snp_blen = SNOOP_MINLEN;
427 snp->snp_base = 0;
428 snp->snp_len = 0;
429
430 /*
431 * snp_tty == NULL is for inactive snoop devices.
432 */
433 snp->snp_tty = NULL;
434 snp->snp_target = NULL;
435
436 LIST_INSERT_HEAD(&snp_sclist, snp, snp_list);
437 return (0);
438}
439
440
441static int
442snp_detach(snp)
443 struct snoop *snp;
444{
445 struct tty *tp;
446
447 snp->snp_base = 0;
448 snp->snp_len = 0;
449
450 /*
451 * If line disc. changed we do not touch this pointer, SLIP/PPP will
452 * change it anyway.
453 */
454 tp = snp->snp_tty;
455 if (tp == NULL)
456 goto detach_notty;
457
458 if ((tp->t_state & TS_SNOOP) && tp->t_line == snooplinedisc) {
459 tp->t_state &= ~TS_SNOOP;
460 tp->t_line = snp->snp_olddisc;
461 } else
462 printf("snp%d: bad attached tty data\n", snp->snp_unit);
463
464 snp->snp_tty = NULL;
465 snp->snp_target = NULL;
466
467detach_notty:
468 selwakeuppri(&snp->snp_sel, PZERO + 1);
469 if ((snp->snp_flags & SNOOP_OPEN) == 0)
470 free(snp, M_SNP);
471
472 return (0);
473}
474
475static int
476snpclose(dev, flags, fmt, td)
477 struct cdev *dev;
478 int flags;
479 int fmt;
480 struct thread *td;
481{
482 struct snoop *snp;
483
484 snp = dev->si_drv1;
485 snp->snp_blen = 0;
486 LIST_REMOVE(snp, snp_list);
487 free(snp->snp_buf, M_SNP);
488 snp->snp_flags &= ~SNOOP_OPEN;
489 dev->si_drv1 = NULL;
490 destroy_dev(dev);
491
492 return (snp_detach(snp));
493}
494
495static int
496snp_down(snp)
497 struct snoop *snp;
498{
499
500 if (snp->snp_blen != SNOOP_MINLEN) {
501 free(snp->snp_buf, M_SNP);
502 snp->snp_buf = malloc(SNOOP_MINLEN, M_SNP, M_WAITOK);
503 snp->snp_blen = SNOOP_MINLEN;
504 }
505 snp->snp_flags |= SNOOP_DOWN;
506
507 return (snp_detach(snp));
508}
509
510static int
511snpioctl(dev, cmd, data, flags, td)
512 struct cdev *dev;
513 u_long cmd;
514 caddr_t data;
515 int flags;
516 struct thread *td;
517{
518 struct snoop *snp;
519 struct tty *tp, *tpo;
520 struct cdev *tdev;
521 int s;
522
523 snp = dev->si_drv1;
524 switch (cmd) {
525 case SNPSTTY:
526#if 0
527 tdev = findcdev(*((dev_t *)data));
528#else
529 tdev = NULL;
530#endif
531 if (tdev == NULL)
532 return (snp_down(snp));
533
534 tp = snpdevtotty(tdev);
535 if (!tp)
536 return (EINVAL);
537 if (tp->t_state & TS_SNOOP)
538 return (EBUSY);
539
540 s = spltty();
541
542 if (snp->snp_target == NULL) {
543 tpo = snp->snp_tty;
544 if (tpo)
545 tpo->t_state &= ~TS_SNOOP;
546 }
547
548 tp->t_state |= TS_SNOOP;
549 snp->snp_olddisc = tp->t_line;
550 tp->t_line = snooplinedisc;
551 snp->snp_tty = tp;
552 snp->snp_target = tdev;
553
554 /*
555 * Clean overflow and down flags -
556 * we'll have a chance to get them in the future :)))
557 */
558 snp->snp_flags &= ~SNOOP_OFLOW;
559 snp->snp_flags &= ~SNOOP_DOWN;
560 splx(s);
561 break;
562
563 case SNPGTTY:
564 /*
565 * We keep snp_target field specially to make
566 * SNPGTTY happy, else we can't know what is device
567 * major/minor for tty.
568 */
569 *((dev_t *)data) = dev2udev(snp->snp_target);
570 break;
571
572 case FIONBIO:
573 break;
574
575 case FIOASYNC:
576 if (*(int *)data)
577 snp->snp_flags |= SNOOP_ASYNC;
578 else
579 snp->snp_flags &= ~SNOOP_ASYNC;
580 break;
581
582 case FIONREAD:
583 s = spltty();
584 if (snp->snp_tty != NULL)
585 *(int *)data = snp->snp_len;
586 else
587 if (snp->snp_flags & SNOOP_DOWN) {
588 if (snp->snp_flags & SNOOP_OFLOW)
589 *(int *)data = SNP_OFLOW;
590 else
591 *(int *)data = SNP_TTYCLOSE;
592 } else {
593 *(int *)data = SNP_DETACH;
594 }
595 splx(s);
596 break;
597
598 default:
599 return (ENOTTY);
600 }
601 return (0);
602}
603
604static int
605snppoll(dev, events, td)
606 struct cdev *dev;
607 int events;
608 struct thread *td;
609{
610 struct snoop *snp;
611 int revents;
612
613 snp = dev->si_drv1;
614 revents = 0;
615 /*
616 * If snoop is down, we don't want to poll() forever so we return 1.
617 * Caller should see if we down via FIONREAD ioctl(). The last should
618 * return -1 to indicate down state.
619 */
620 if (events & (POLLIN | POLLRDNORM)) {
621 if (snp->snp_flags & SNOOP_DOWN || snp->snp_len > 0)
622 revents |= events & (POLLIN | POLLRDNORM);
623 else
624 selrecord(td, &snp->snp_sel);
625 }
626 return (revents);
627}
628
629static void
630snp_clone(arg, name, namelen, dev)
631 void *arg;
632 char *name;
633 int namelen;
634 struct cdev **dev;
635{
636 int u, i;
637
638 if (*dev != NULL)
639 return;
640 if (dev_stdclone(name, NULL, "snp", &u) != 1)
641 return;
642 i = clone_create(&snpclones, &snp_cdevsw, &u, dev, 0);
643 if (i)
644 *dev = make_dev(&snp_cdevsw, unit2minor(u),
645 UID_ROOT, GID_WHEEL, 0600, "snp%d", u);
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