1 /* $NetBSD: output.c,v 1.42 2024/10/03 20:14:01 rillig Exp $ */
2
3 /*-
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
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. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35 #include <sys/cdefs.h>
36 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)output.c 8.2 (Berkeley) 5/4/95";
39 #else
40 __RCSID("$NetBSD: output.c,v 1.42 2024/10/03 20:14:01 rillig Exp $");
41 #endif
42 #endif /* not lint */
43
44 /*
45 * Shell output routines. We use our own output routines because:
46 * When a builtin command is interrupted we have to discard
47 * any pending output.
48 * When a builtin command appears in back quotes, we want to
49 * save the output of the command in a region obtained
50 * via malloc, rather than doing a fork and reading the
51 * output of the command via a pipe.
52 * Our output routines may be smaller than the stdio routines.
53 */
54
55 #include <sys/types.h> /* quad_t */
56 #include <sys/param.h> /* BSD4_4 */
57 #include <sys/ioctl.h>
58
59 #include <stdio.h> /* defines BUFSIZ */
60 #include <string.h>
61 #include <errno.h>
62 #include <unistd.h>
63 #include <stdlib.h>
64
65 #include "shell.h"
66 #include "syntax.h"
67 #include "output.h"
68 #include "memalloc.h"
69 #include "error.h"
70 #include "redir.h"
71 #include "options.h"
72 #include "show.h"
73
74
75 #define OUTBUFSIZ BUFSIZ
76 #define BLOCK_OUT -2 /* output to a fixed block of memory */
77 #define MEM_OUT -3 /* output to dynamically allocated memory */
78
79 #ifdef SMALL
80 #define CHAIN
81 #else
82 #define CHAIN ,NULL
83 #endif
84
85
86 /* nextc nleft bufsize buf fd flags chain */
87 struct output output = {NULL, 0, OUTBUFSIZ, NULL, 1, 0 CHAIN };
88 struct output errout = {NULL, 0, 100, NULL, 2, 0 CHAIN };
89 struct output memout = {NULL, 0, 0, NULL, MEM_OUT, 0 CHAIN };
90 struct output *out1 = &output;
91 struct output *out2 = &errout;
92 #ifndef SMALL
93 struct output *outx = &errout;
94 struct output *outxtop = NULL;
95 #endif
96
97
98 #ifdef mkinit
99
100 INCLUDE "output.h"
101 INCLUDE "memalloc.h"
102
103 RESET {
104 out1 = &output;
105 out2 = &errout;
106 if (memout.buf != NULL) {
107 ckfree(memout.buf);
108 memout.buf = NULL;
109 }
110 }
111
112 #endif
113
114
115 #ifdef notdef /* no longer used */
116 /*
117 * Set up an output file to write to memory rather than a file.
118 */
119
120 void
open_mem(char * block,int length,struct output * file)121 open_mem(char *block, int length, struct output *file)
122 {
123 file->nextc = block;
124 file->nleft = --length;
125 file->fd = BLOCK_OUT;
126 file->flags = 0;
127 }
128 #endif
129
130
131 void
out1str(const char * p)132 out1str(const char *p)
133 {
134 outstr(p, out1);
135 }
136
137
138 void
out2str(const char * p)139 out2str(const char *p)
140 {
141 outstr(p, out2);
142 }
143
144 #ifndef SMALL
145 void
outxstr(const char * p)146 outxstr(const char *p)
147 {
148 outstr(p, outx);
149 }
150 #endif
151
152
153 void
outstr(const char * p,struct output * file)154 outstr(const char *p, struct output *file)
155 {
156 char c = 0;
157
158 while (*p)
159 outc((c = *p++), file);
160 if (file == out2 || (file == outx && c == '\n'))
161 flushout(file);
162 }
163
164
165 void
out2shstr(const char * p)166 out2shstr(const char *p)
167 {
168 outshstr(p, out2);
169 }
170
171 #ifndef SMALL
172 void
outxshstr(const char * p)173 outxshstr(const char *p)
174 {
175 outshstr(p, outx);
176 }
177 #endif
178
179 /*
180 * ' is in this list, not because it does not require quoting
181 * (which applies to all the others) but because '' quoting cannot
182 * be used to quote it.
183 */
184 static const char norm_chars [] = \
185 "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789/+-=_,.'";
186
187 static int
inquote(const char * p)188 inquote(const char *p)
189 {
190 size_t l = strspn(p, norm_chars);
191 const char *s = strchr(p, '\'');
192
193 return s == NULL ? p[l] != '\0' : s - p > (off_t)l;
194 }
195
196 void
outshstr(const char * p,struct output * file)197 outshstr(const char *p, struct output *file)
198 {
199 int need_q;
200 int inq;
201 char c;
202
203 if (strchr(p, '\'') != NULL && p[1] != '\0') {
204 /*
205 * string contains ' in it, and is not only the '
206 * see if " quoting will work
207 */
208 size_t i = strcspn(p, "\\\"$`");
209
210 if (p[i] == '\0') {
211 /*
212 * string contains no $ ` \ or " chars, perfect...
213 *
214 * We know it contains ' so needs quoting, so
215 * this is easy...
216 */
217 outc('"', file);
218 outstr(p, file);
219 outc('"', file);
220 return;
221 }
222 }
223
224 need_q = p[0] == 0 || p[strspn(p, norm_chars)] != 0;
225
226 /*
227 * Don't emit ' unless something needs quoting before closing '
228 */
229 if (need_q && (p[0] == 0 || inquote(p) != 0)) {
230 outc('\'', file);
231 inq = 1;
232 } else
233 inq = 0;
234
235 while ((c = *p++) != '\0') {
236 if (c != '\'') {
237 outc(c, file);
238 continue;
239 }
240
241 if (inq)
242 outc('\'', file); /* inq = 0, implicit */
243 outc('\\', file);
244 outc(c, file);
245 if (need_q && *p != '\0') {
246 if ((inq = inquote(p)) != 0)
247 outc('\'', file);
248 } else
249 inq = 0;
250 }
251
252 if (inq)
253 outc('\'', file);
254
255 if (file == out2)
256 flushout(file);
257 }
258
259
260 char out_junk[16];
261
262
263 void
emptyoutbuf(struct output * dest)264 emptyoutbuf(struct output *dest)
265 {
266 int offset;
267
268 if (dest->fd == BLOCK_OUT) {
269 dest->nextc = out_junk;
270 dest->nleft = sizeof out_junk;
271 dest->flags |= OUTPUT_ERR;
272 } else if (dest->buf == NULL) {
273 INTOFF;
274 dest->buf = ckmalloc(dest->bufsize);
275 dest->nextc = dest->buf;
276 dest->nleft = dest->bufsize;
277 INTON;
278 VTRACE(DBG_OUTPUT, ("emptyoutbuf now %d @%p for fd %d\n",
279 dest->nleft, dest->buf, dest->fd));
280 } else if (dest->fd == MEM_OUT) {
281 offset = dest->bufsize;
282 INTOFF;
283 dest->bufsize <<= 1;
284 dest->buf = ckrealloc(dest->buf, dest->bufsize);
285 dest->nleft = dest->bufsize - offset;
286 dest->nextc = dest->buf + offset;
287 INTON;
288 } else {
289 flushout(dest);
290 }
291 dest->nleft--;
292 }
293
294
295 void
flushall(void)296 flushall(void)
297 {
298 flushout(&output);
299 flushout(&errout);
300 }
301
302
303 void
flushout(struct output * dest)304 flushout(struct output *dest)
305 {
306
307 if (dest->buf == NULL || dest->nextc == dest->buf || dest->fd < 0)
308 return;
309 VTRACE(DBG_OUTPUT, ("flushout fd=%d %zd to write\n", dest->fd,
310 (size_t)(dest->nextc - dest->buf)));
311 if (xwrite(dest->fd, dest->buf, dest->nextc - dest->buf) < 0)
312 dest->flags |= OUTPUT_ERR;
313 dest->nextc = dest->buf;
314 dest->nleft = dest->bufsize;
315 }
316
317
318 void
freestdout(void)319 freestdout(void)
320 {
321 INTOFF;
322 if (output.buf) {
323 ckfree(output.buf);
324 output.buf = NULL;
325 output.nleft = 0;
326 }
327 INTON;
328 }
329
330
331 void
outfmt(struct output * file,const char * fmt,...)332 outfmt(struct output *file, const char *fmt, ...)
333 {
334 va_list ap;
335
336 va_start(ap, fmt);
337 doformat(file, fmt, ap);
338 va_end(ap);
339 }
340
341
342 void
out1fmt(const char * fmt,...)343 out1fmt(const char *fmt, ...)
344 {
345 va_list ap;
346
347 va_start(ap, fmt);
348 doformat(out1, fmt, ap);
349 va_end(ap);
350 }
351
352 #ifdef DEBUG
353 void
debugprintf(const char * fmt,...)354 debugprintf(const char *fmt, ...)
355 {
356 va_list ap;
357
358 va_start(ap, fmt);
359 doformat(out2, fmt, ap);
360 va_end(ap);
361 flushout(out2);
362 }
363 #endif
364
365 void
fmtstr(char * outbuf,size_t length,const char * fmt,...)366 fmtstr(char *outbuf, size_t length, const char *fmt, ...)
367 {
368 va_list ap;
369 struct output strout;
370
371 va_start(ap, fmt);
372 strout.nextc = outbuf;
373 strout.nleft = length;
374 strout.fd = BLOCK_OUT;
375 strout.flags = 0;
376 doformat(&strout, fmt, ap);
377 outc('\0', &strout);
378 if (strout.flags & OUTPUT_ERR)
379 outbuf[length - 1] = '\0';
380 va_end(ap);
381 }
382
383 /*
384 * Formatted output. This routine handles a subset of the printf formats:
385 * - Formats supported: d, u, o, p, X, s, and c.
386 * - The x format is also accepted but is treated like X.
387 * - The l, ll and q modifiers are accepted.
388 * - The - and # flags are accepted; # only works with the o format.
389 * - Width and precision may be specified with any format except c.
390 * - An * may be given for the width or precision.
391 * - The obsolete practice of preceding the width with a zero to get
392 * zero padding is not supported; use the precision field.
393 * - A % may be printed by writing %% in the format string.
394 */
395
396 #define TEMPSIZE 24
397
398 #ifdef BSD4_4
399 #define HAVE_VASPRINTF 1
400 #endif
401
402 void
doformat(struct output * dest,const char * f,va_list ap)403 doformat(struct output *dest, const char *f, va_list ap)
404 {
405 #if HAVE_VASPRINTF
406 char *s;
407
408 vasprintf(&s, f, ap);
409 if (s == NULL)
410 error("Could not allocate formatted output buffer");
411 outstr(s, dest);
412 free(s);
413 #else /* !HAVE_VASPRINTF */
414 static const char digit[] = "0123456789ABCDEF";
415 char c;
416 char temp[TEMPSIZE];
417 int flushleft;
418 int sharp;
419 int width;
420 int prec;
421 int islong;
422 int isquad;
423 char *p;
424 int sign;
425 #ifdef BSD4_4
426 quad_t l;
427 u_quad_t num;
428 #else
429 long l;
430 u_long num;
431 #endif
432 unsigned base;
433 int len;
434 int size;
435 int pad;
436
437 while ((c = *f++) != '\0') {
438 if (c != '%') {
439 outc(c, dest);
440 continue;
441 }
442 flushleft = 0;
443 sharp = 0;
444 width = 0;
445 prec = -1;
446 islong = 0;
447 isquad = 0;
448 for (;;) {
449 if (*f == '-')
450 flushleft++;
451 else if (*f == '#')
452 sharp++;
453 else
454 break;
455 f++;
456 }
457 if (*f == '*') {
458 width = va_arg(ap, int);
459 f++;
460 } else {
461 while (is_digit(*f)) {
462 width = 10 * width + digit_val(*f++);
463 }
464 }
465 if (*f == '.') {
466 if (*++f == '*') {
467 prec = va_arg(ap, int);
468 f++;
469 } else {
470 prec = 0;
471 while (is_digit(*f)) {
472 prec = 10 * prec + digit_val(*f++);
473 }
474 }
475 }
476 if (*f == 'l') {
477 f++;
478 if (*f == 'l') {
479 isquad++;
480 f++;
481 } else
482 islong++;
483 } else if (*f == 'q') {
484 isquad++;
485 f++;
486 }
487 switch (*f) {
488 case 'd':
489 #ifdef BSD4_4
490 if (isquad)
491 l = va_arg(ap, quad_t);
492 else
493 #endif
494 if (islong)
495 l = va_arg(ap, long);
496 else
497 l = va_arg(ap, int);
498 sign = 0;
499 num = l;
500 if (l < 0) {
501 num = -l;
502 sign = 1;
503 }
504 base = 10;
505 goto number;
506 case 'u':
507 base = 10;
508 goto uns_number;
509 case 'o':
510 base = 8;
511 goto uns_number;
512 case 'p':
513 outc('0', dest);
514 outc('x', dest);
515 /*FALLTHROUGH*/
516 case 'x':
517 /* we don't implement 'x'; treat like 'X' */
518 case 'X':
519 base = 16;
520 uns_number: /* an unsigned number */
521 sign = 0;
522 #ifdef BSD4_4
523 if (isquad)
524 num = va_arg(ap, u_quad_t);
525 else
526 #endif
527 if (islong)
528 num = va_arg(ap, unsigned long);
529 else
530 num = va_arg(ap, unsigned int);
531 number: /* process a number */
532 p = temp + TEMPSIZE - 1;
533 *p = '\0';
534 while (num) {
535 *--p = digit[num % base];
536 num /= base;
537 }
538 len = (temp + TEMPSIZE - 1) - p;
539 if (prec < 0)
540 prec = 1;
541 if (sharp && *f == 'o' && prec <= len)
542 prec = len + 1;
543 pad = 0;
544 if (width) {
545 size = len;
546 if (size < prec)
547 size = prec;
548 size += sign;
549 pad = width - size;
550 if (flushleft == 0) {
551 while (--pad >= 0)
552 outc(' ', dest);
553 }
554 }
555 if (sign)
556 outc('-', dest);
557 prec -= len;
558 while (--prec >= 0)
559 outc('0', dest);
560 while (*p)
561 outc(*p++, dest);
562 while (--pad >= 0)
563 outc(' ', dest);
564 break;
565 case 's':
566 p = va_arg(ap, char *);
567 pad = 0;
568 if (width) {
569 len = strlen(p);
570 if (prec >= 0 && len > prec)
571 len = prec;
572 pad = width - len;
573 if (flushleft == 0) {
574 while (--pad >= 0)
575 outc(' ', dest);
576 }
577 }
578 prec++;
579 while (--prec != 0 && *p)
580 outc(*p++, dest);
581 while (--pad >= 0)
582 outc(' ', dest);
583 break;
584 case 'c':
585 c = va_arg(ap, int);
586 outc(c, dest);
587 break;
588 default:
589 outc(*f, dest);
590 break;
591 }
592 f++;
593 }
594 #endif /* !HAVE_VASPRINTF */
595 }
596
597
598
599 /*
600 * Version of write which resumes after a signal is caught.
601 */
602
603 int
xwrite(int fd,char * buf,int nbytes)604 xwrite(int fd, char *buf, int nbytes)
605 {
606 int ntry;
607 int i;
608 int n;
609
610 n = nbytes;
611 ntry = 0;
612 while (n > 0) {
613 i = write(fd, buf, n);
614 if (i > 0) {
615 if ((n -= i) <= 0)
616 return nbytes;
617 buf += i;
618 ntry = 0;
619 } else if (i == 0) {
620 if (++ntry > 10)
621 return nbytes - n;
622 } else if (errno != EINTR) {
623 return -1;
624 }
625 }
626 return nbytes;
627 }
628
629 #ifndef SMALL
630 static void
xtrace_fd_swap(int from,int to)631 xtrace_fd_swap(int from, int to)
632 {
633 struct output *o = outxtop;
634
635 while (o != NULL) {
636 if (o->fd == from)
637 o->fd = to;
638 o = o->chain;
639 }
640 }
641
642 /*
643 * the -X flag is to be set or reset (not necessarily changed)
644 * Do what is needed to make tracing go to where it should
645 *
646 * Note: Xflag has not yet been altered, "on" indicates what it will become
647 */
648
649 void
xtracefdsetup(int on)650 xtracefdsetup(int on)
651 {
652 if (!on) {
653 flushout(outx);
654
655 if (Xflag != 1) /* Was already +X */
656 return; /* so nothing to do */
657
658 outx = out2;
659 CTRACE(DBG_OUTPUT, ("Tracing to stderr\n"));
660 return;
661 }
662
663 if (Xflag == 1) { /* was already set */
664 /*
665 * This is a change of output file only
666 * Just close the current one, and reuse the struct output
667 */
668 if (!(outx->flags & OUTPUT_CLONE))
669 sh_close(outx->fd);
670 } else if (outxtop == NULL) {
671 /*
672 * -X is just turning on, for the forst time,
673 * need a new output struct to become outx
674 */
675 xtrace_clone(1);
676 } else
677 outx = outxtop;
678
679 if (outx != out2) {
680 outx->flags &= ~OUTPUT_CLONE;
681 outx->fd = to_upper_fd(dup(out2->fd));
682 register_sh_fd(outx->fd, xtrace_fd_swap);
683 }
684
685 CTRACE(DBG_OUTPUT, ("Tracing now to fd %d (from %d)\n",
686 outx->fd, out2->fd));
687 }
688
689 void
xtrace_clone(int new)690 xtrace_clone(int new)
691 {
692 struct output *o;
693
694 CTRACE(DBG_OUTPUT,
695 ("xtrace_clone(%d): %sfd=%d buf=%p nleft=%d flags=%x ",
696 new, (outx == out2 ? "out2: " : ""),
697 outx->fd, outx->buf, outx->nleft, outx->flags));
698
699 flushout(outx);
700
701 if (!new && outxtop == NULL && Xflag == 0) {
702 /* following stderr, nothing to save */
703 CTRACE(DBG_OUTPUT, ("+X\n"));
704 return;
705 }
706
707 o = ckmalloc(sizeof(*o));
708 o->fd = outx->fd;
709 o->flags = OUTPUT_CLONE;
710 o->bufsize = outx->bufsize;
711 o->nleft = 0;
712 o->buf = NULL;
713 o->nextc = NULL;
714 o->chain = outxtop;
715 outx = o;
716 outxtop = o;
717
718 CTRACE(DBG_OUTPUT, ("-> fd=%d flags=%x[CLONE]\n", outx->fd, o->flags));
719 }
720
721 void
xtrace_pop(void)722 xtrace_pop(void)
723 {
724 struct output *o;
725
726 CTRACE(DBG_OUTPUT, ("trace_pop: fd=%d buf=%p nleft=%d flags=%x ",
727 outx->fd, outx->buf, outx->nleft, outx->flags));
728
729 flushout(outx);
730
731 if (outxtop == NULL) {
732 /*
733 * No -X has been used, so nothing much to do
734 */
735 CTRACE(DBG_OUTPUT, ("+X\n"));
736 return;
737 }
738
739 o = outxtop;
740 outx = o->chain;
741 if (outx == NULL)
742 outx = &errout;
743 outxtop = o->chain;
744 if (o != &errout) {
745 if (o->fd >= 0 && !(o->flags & OUTPUT_CLONE))
746 sh_close(o->fd);
747 if (o->buf)
748 ckfree(o->buf);
749 ckfree(o);
750 }
751
752 CTRACE(DBG_OUTPUT, ("-> fd=%d buf=%p nleft=%d flags=%x\n",
753 outx->fd, outx->buf, outx->nleft, outx->flags));
754 }
755 #endif /* SMALL */
756