tty_subr.c revision 1.20 1 /* $NetBSD: tty_subr.c,v 1.20 2000/08/02 20:53:07 thorpej Exp $ */
2
3 /*
4 * Copyright (c) 1993, 1994 Theo de Raadt
5 * All rights reserved.
6 *
7 * Per Lindqvist <pgd (at) compuram.bbt.se> supplied an almost fully working
8 * set of true clist functions that this is very loosely based on.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by Theo de Raadt.
21 * 4. The name of the author may not be used to endorse or promote products
22 * derived from this software without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/buf.h>
39 #include <sys/ioctl.h>
40 #include <sys/tty.h>
41 #include <sys/malloc.h>
42
43 /*
44 * At compile time, choose:
45 * There are two ways the TTY_QUOTE bit can be stored. If QBITS is
46 * defined we allocate an array of bits -- 1/8th as much memory but
47 * setbit(), clrbit(), and isset() take more cpu. If QBITS is
48 * undefined, we just use an array of bytes.
49 *
50 * If TTY_QUOTE functionality isn't required by a line discipline,
51 * it can free c_cq and set it to NULL. This speeds things up,
52 * and also does not use any extra memory. This is useful for (say)
53 * a SLIP line discipline that wants a 32K ring buffer for data
54 * but doesn't need quoting.
55 */
56 #define QBITS
57
58 #ifdef QBITS
59 #define QMEM(n) ((((n)-1)/NBBY)+1)
60 #else
61 #define QMEM(n) (n)
62 #endif
63
64 void cinit __P((void));
65 #ifdef QBITS
66 void clrbits __P((u_char *, int, int));
67 #endif
68
69 /*
70 * Initialize clists.
71 */
72 void
73 cinit()
74 {
75 }
76
77 /*
78 * Initialize a particular clist. Ok, they are really ring buffers,
79 * of the specified length, with/without quoting support.
80 */
81 int
82 clalloc(clp, size, quot)
83 struct clist *clp;
84 int size;
85 int quot;
86 {
87
88 clp->c_cs = malloc(size, M_TTYS, M_WAITOK);
89 if (!clp->c_cs)
90 return (-1);
91 memset(clp->c_cs, 0, size);
92
93 if(quot) {
94 clp->c_cq = malloc(QMEM(size), M_TTYS, M_WAITOK);
95 if (!clp->c_cq) {
96 free(clp->c_cs, M_TTYS);
97 return (-1);
98 }
99 memset(clp->c_cs, 0, QMEM(size));
100 } else
101 clp->c_cq = (u_char *)0;
102
103 clp->c_cf = clp->c_cl = (u_char *)0;
104 clp->c_ce = clp->c_cs + size;
105 clp->c_cn = size;
106 clp->c_cc = 0;
107 return (0);
108 }
109
110 void
111 clfree(clp)
112 struct clist *clp;
113 {
114 if(clp->c_cs)
115 free(clp->c_cs, M_TTYS);
116 if(clp->c_cq)
117 free(clp->c_cq, M_TTYS);
118 clp->c_cs = clp->c_cq = (u_char *)0;
119 }
120
121
122 /*
123 * Get a character from a clist.
124 */
125 int
126 getc(clp)
127 struct clist *clp;
128 {
129 int c = -1;
130 int s;
131
132 s = spltty();
133 if (clp->c_cc == 0)
134 goto out;
135
136 c = *clp->c_cf & 0xff;
137 if (clp->c_cq) {
138 #ifdef QBITS
139 if (isset(clp->c_cq, clp->c_cf - clp->c_cs) )
140 c |= TTY_QUOTE;
141 #else
142 if (*(clp->c_cf - clp->c_cs + clp->c_cq))
143 c |= TTY_QUOTE;
144 #endif
145 }
146 if (++clp->c_cf == clp->c_ce)
147 clp->c_cf = clp->c_cs;
148 if (--clp->c_cc == 0)
149 clp->c_cf = clp->c_cl = (u_char *)0;
150 out:
151 splx(s);
152 return c;
153 }
154
155 /*
156 * Copy clist to buffer.
157 * Return number of bytes moved.
158 */
159 int
160 q_to_b(clp, cp, count)
161 struct clist *clp;
162 u_char *cp;
163 int count;
164 {
165 int cc;
166 u_char *p = cp;
167 int s;
168
169 s = spltty();
170 /* optimize this while loop */
171 while (count > 0 && clp->c_cc > 0) {
172 cc = clp->c_cl - clp->c_cf;
173 if (clp->c_cf >= clp->c_cl)
174 cc = clp->c_ce - clp->c_cf;
175 if (cc > count)
176 cc = count;
177 memcpy(p, clp->c_cf, cc);
178 count -= cc;
179 p += cc;
180 clp->c_cc -= cc;
181 clp->c_cf += cc;
182 if (clp->c_cf == clp->c_ce)
183 clp->c_cf = clp->c_cs;
184 }
185 if (clp->c_cc == 0)
186 clp->c_cf = clp->c_cl = (u_char *)0;
187 splx(s);
188 return p - cp;
189 }
190
191 /*
192 * Return count of contiguous characters in clist.
193 * Stop counting if flag&character is non-null.
194 */
195 int
196 ndqb(clp, flag)
197 struct clist *clp;
198 int flag;
199 {
200 int count = 0;
201 int i;
202 int cc;
203 int s;
204
205 s = spltty();
206 if ((cc = clp->c_cc) == 0)
207 goto out;
208
209 if (flag == 0) {
210 count = clp->c_cl - clp->c_cf;
211 if (count <= 0)
212 count = clp->c_ce - clp->c_cf;
213 goto out;
214 }
215
216 i = clp->c_cf - clp->c_cs;
217 if (flag & TTY_QUOTE) {
218 while (cc-- > 0 && !(clp->c_cs[i++] & (flag & ~TTY_QUOTE) ||
219 isset(clp->c_cq, i))) {
220 count++;
221 if (i == clp->c_cn)
222 break;
223 }
224 } else {
225 while (cc-- > 0 && !(clp->c_cs[i++] & flag)) {
226 count++;
227 if (i == clp->c_cn)
228 break;
229 }
230 }
231 out:
232 splx(s);
233 return count;
234 }
235
236 /*
237 * Flush count bytes from clist.
238 */
239 void
240 ndflush(clp, count)
241 struct clist *clp;
242 int count;
243 {
244 int cc;
245 int s;
246
247 s = spltty();
248 if (count == clp->c_cc) {
249 clp->c_cc = 0;
250 clp->c_cf = clp->c_cl = (u_char *)0;
251 goto out;
252 }
253 /* optimize this while loop */
254 while (count > 0 && clp->c_cc > 0) {
255 cc = clp->c_cl - clp->c_cf;
256 if (clp->c_cf >= clp->c_cl)
257 cc = clp->c_ce - clp->c_cf;
258 if (cc > count)
259 cc = count;
260 count -= cc;
261 clp->c_cc -= cc;
262 clp->c_cf += cc;
263 if (clp->c_cf == clp->c_ce)
264 clp->c_cf = clp->c_cs;
265 }
266 if (clp->c_cc == 0)
267 clp->c_cf = clp->c_cl = (u_char *)0;
268 out:
269 splx(s);
270 }
271
272 /*
273 * Put a character into the output queue.
274 */
275 int
276 putc(c, clp)
277 int c;
278 struct clist *clp;
279 {
280 int i;
281 int s;
282
283 s = spltty();
284 if (clp->c_cc == clp->c_cn)
285 goto out;
286
287 if (clp->c_cc == 0) {
288 if (!clp->c_cs) {
289 #if defined(DIAGNOSTIC) || 1
290 printf("putc: required clalloc\n");
291 #endif
292 if(clalloc(clp, 1024, 1)) {
293 out:
294 splx(s);
295 return -1;
296 }
297 }
298 clp->c_cf = clp->c_cl = clp->c_cs;
299 }
300
301 *clp->c_cl = c & 0xff;
302 i = clp->c_cl - clp->c_cs;
303 if (clp->c_cq) {
304 #ifdef QBITS
305 if (c & TTY_QUOTE)
306 setbit(clp->c_cq, i);
307 else
308 clrbit(clp->c_cq, i);
309 #else
310 q = clp->c_cq + i;
311 *q = (c & TTY_QUOTE) ? 1 : 0;
312 #endif
313 }
314 clp->c_cc++;
315 clp->c_cl++;
316 if (clp->c_cl == clp->c_ce)
317 clp->c_cl = clp->c_cs;
318 splx(s);
319 return 0;
320 }
321
322 #ifdef QBITS
323 /*
324 * optimized version of
325 *
326 * for (i = 0; i < len; i++)
327 * clrbit(cp, off + len);
328 */
329 void
330 clrbits(cp, off, len)
331 u_char *cp;
332 int off;
333 int len;
334 {
335 int sby, sbi, eby, ebi;
336 int i;
337 u_char mask;
338
339 if(len==1) {
340 clrbit(cp, off);
341 return;
342 }
343
344 sby = off / NBBY;
345 sbi = off % NBBY;
346 eby = (off+len) / NBBY;
347 ebi = (off+len) % NBBY;
348 if (sby == eby) {
349 mask = ((1 << (ebi - sbi)) - 1) << sbi;
350 cp[sby] &= ~mask;
351 } else {
352 mask = (1<<sbi) - 1;
353 cp[sby++] &= mask;
354
355 mask = (1<<ebi) - 1;
356 cp[eby] &= ~mask;
357
358 for (i = sby; i < eby; i++)
359 cp[i] = 0x00;
360 }
361 }
362 #endif
363
364 /*
365 * Copy buffer to clist.
366 * Return number of bytes not transfered.
367 */
368 int
369 b_to_q(cp, count, clp)
370 const u_char *cp;
371 int count;
372 struct clist *clp;
373 {
374 int cc;
375 const u_char *p = cp;
376 int s;
377
378 if (count <= 0)
379 return 0;
380
381 s = spltty();
382 if (clp->c_cc == clp->c_cn)
383 goto out;
384
385 if (clp->c_cc == 0) {
386 if (!clp->c_cs) {
387 #if defined(DIAGNOSTIC) || 1
388 printf("b_to_q: required clalloc\n");
389 #endif
390 if(clalloc(clp, 1024, 1))
391 goto out;
392 }
393 clp->c_cf = clp->c_cl = clp->c_cs;
394 }
395
396 /* optimize this while loop */
397 while (count > 0 && clp->c_cc < clp->c_cn) {
398 cc = clp->c_ce - clp->c_cl;
399 if (clp->c_cf > clp->c_cl)
400 cc = clp->c_cf - clp->c_cl;
401 if (cc > count)
402 cc = count;
403 memcpy(clp->c_cl, p, cc);
404 if (clp->c_cq) {
405 #ifdef QBITS
406 clrbits(clp->c_cq, clp->c_cl - clp->c_cs, cc);
407 #else
408 memset(clp->c_cl - clp->c_cs + clp->c_cq, 0, cc);
409 #endif
410 }
411 p += cc;
412 count -= cc;
413 clp->c_cc += cc;
414 clp->c_cl += cc;
415 if (clp->c_cl == clp->c_ce)
416 clp->c_cl = clp->c_cs;
417 }
418 out:
419 splx(s);
420 return count;
421 }
422
423 static int cc;
424
425 /*
426 * Given a non-NULL pointer into the clist return the pointer
427 * to the next character in the list or return NULL if no more chars.
428 *
429 * Callers must not allow getc's to happen between firstc's and getc's
430 * so that the pointer becomes invalid. Note that interrupts are NOT
431 * masked.
432 */
433 u_char *
434 nextc(clp, cp, c)
435 struct clist *clp;
436 u_char *cp;
437 int *c;
438 {
439
440 if (clp->c_cf == cp) {
441 /*
442 * First time initialization.
443 */
444 cc = clp->c_cc;
445 }
446 if (cc == 0 || cp == NULL)
447 return NULL;
448 if (--cc == 0)
449 return NULL;
450 if (++cp == clp->c_ce)
451 cp = clp->c_cs;
452 *c = *cp & 0xff;
453 if (clp->c_cq) {
454 #ifdef QBITS
455 if (isset(clp->c_cq, cp - clp->c_cs))
456 *c |= TTY_QUOTE;
457 #else
458 if (*(clp->c_cf - clp->c_cs + clp->c_cq))
459 *c |= TTY_QUOTE;
460 #endif
461 }
462 return cp;
463 }
464
465 /*
466 * Given a non-NULL pointer into the clist return the pointer
467 * to the first character in the list or return NULL if no more chars.
468 *
469 * Callers must not allow getc's to happen between firstc's and getc's
470 * so that the pointer becomes invalid. Note that interrupts are NOT
471 * masked.
472 *
473 * *c is set to the NEXT character
474 */
475 u_char *
476 firstc(clp, c)
477 struct clist *clp;
478 int *c;
479 {
480 u_char *cp;
481
482 cc = clp->c_cc;
483 if (cc == 0)
484 return NULL;
485 cp = clp->c_cf;
486 *c = *cp & 0xff;
487 if(clp->c_cq) {
488 #ifdef QBITS
489 if (isset(clp->c_cq, cp - clp->c_cs))
490 *c |= TTY_QUOTE;
491 #else
492 if (*(cp - clp->c_cs + clp->c_cq))
493 *c |= TTY_QUOTE;
494 #endif
495 }
496 return clp->c_cf;
497 }
498
499 /*
500 * Remove the last character in the clist and return it.
501 */
502 int
503 unputc(clp)
504 struct clist *clp;
505 {
506 unsigned int c = -1;
507 int s;
508
509 s = spltty();
510 if (clp->c_cc == 0)
511 goto out;
512
513 if (clp->c_cl == clp->c_cs)
514 clp->c_cl = clp->c_ce - 1;
515 else
516 --clp->c_cl;
517 clp->c_cc--;
518
519 c = *clp->c_cl & 0xff;
520 if (clp->c_cq) {
521 #ifdef QBITS
522 if (isset(clp->c_cq, clp->c_cl - clp->c_cs))
523 c |= TTY_QUOTE;
524 #else
525 if (*(clp->c_cf - clp->c_cs + clp->c_cq))
526 c |= TTY_QUOTE;
527 #endif
528 }
529 if (clp->c_cc == 0)
530 clp->c_cf = clp->c_cl = (u_char *)0;
531 out:
532 splx(s);
533 return c;
534 }
535
536 /*
537 * Put the chars in the from queue on the end of the to queue.
538 */
539 void
540 catq(from, to)
541 struct clist *from, *to;
542 {
543 int c;
544
545 while ((c = getc(from)) != -1)
546 putc(c, to);
547 }
548