1 /*	$OpenBSD: shf.c,v 1.16 2013/04/19 17:36:09 millert Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2011,
5  *		 2012, 2013, 2015
6  *	mirabilos <m@mirbsd.org>
7  *
8  * Provided that these terms and disclaimer and all copyright notices
9  * are retained or reproduced in an accompanying document, permission
10  * is granted to deal in this work without restriction, including un-
11  * limited rights to use, publicly perform, distribute, sell, modify,
12  * merge, give away, or sublicence.
13  *
14  * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
15  * the utmost extent permitted by applicable law, neither express nor
16  * implied; without malicious intent or gross negligence. In no event
17  * may a licensor, author or contributor be held liable for indirect,
18  * direct, other damage, loss, or other issues arising in any way out
19  * of dealing in the work, even if advised of the possibility of such
20  * damage or existence of a defect, except proven that it results out
21  * of said person's immediate fault when using the work as intended.
22  *-
23  * Use %zX instead of %p and floating point isn't supported at all.
24  */
25 
26 #include "sh.h"
27 
28 __RCSID("$MirOS: src/bin/mksh/shf.c,v 1.69 2015/12/31 20:38:59 tg Exp $");
29 
30 /* flags to shf_emptybuf() */
31 #define EB_READSW	0x01	/* about to switch to reading */
32 #define EB_GROW		0x02	/* grow buffer if necessary (STRING+DYNAMIC) */
33 
34 /*
35  * Replacement stdio routines. Stdio is too flakey on too many machines
36  * to be useful when you have multiple processes using the same underlying
37  * file descriptors.
38  */
39 
40 static int shf_fillbuf(struct shf *);
41 static int shf_emptybuf(struct shf *, int);
42 
43 /*
44  * Open a file. First three args are for open(), last arg is flags for
45  * this package. Returns NULL if file could not be opened, or if a dup
46  * fails.
47  */
48 struct shf *
shf_open(const char * name,int oflags,int mode,int sflags)49 shf_open(const char *name, int oflags, int mode, int sflags)
50 {
51 	struct shf *shf;
52 	ssize_t bsize =
53 	    /* at most 512 */
54 	    sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE;
55 	int fd, eno;
56 
57 	/* Done before open so if alloca fails, fd won't be lost. */
58 	shf = alloc(sizeof(struct shf) + bsize, ATEMP);
59 	shf->areap = ATEMP;
60 	shf->buf = (unsigned char *)&shf[1];
61 	shf->bsize = bsize;
62 	shf->flags = SHF_ALLOCS;
63 	/* Rest filled in by reopen. */
64 
65 	fd = binopen3(name, oflags, mode);
66 	if (fd < 0) {
67 		eno = errno;
68 		afree(shf, shf->areap);
69 		errno = eno;
70 		return (NULL);
71 	}
72 	if ((sflags & SHF_MAPHI) && fd < FDBASE) {
73 		int nfd;
74 
75 		nfd = fcntl(fd, F_DUPFD, FDBASE);
76 		eno = errno;
77 		close(fd);
78 		if (nfd < 0) {
79 			afree(shf, shf->areap);
80 			errno = eno;
81 			return (NULL);
82 		}
83 		fd = nfd;
84 	}
85 	sflags &= ~SHF_ACCMODE;
86 	sflags |= (oflags & O_ACCMODE) == O_RDONLY ? SHF_RD :
87 	    ((oflags & O_ACCMODE) == O_WRONLY ? SHF_WR : SHF_RDWR);
88 
89 	return (shf_reopen(fd, sflags, shf));
90 }
91 
92 /* helper function for shf_fdopen and shf_reopen */
93 static void
shf_open_hlp(int fd,int * sflagsp,const char * where)94 shf_open_hlp(int fd, int *sflagsp, const char *where)
95 {
96 	int sflags = *sflagsp;
97 
98 	/* use fcntl() to figure out correct read/write flags */
99 	if (sflags & SHF_GETFL) {
100 		int flags = fcntl(fd, F_GETFL, 0);
101 
102 		if (flags < 0)
103 			/* will get an error on first read/write */
104 			sflags |= SHF_RDWR;
105 		else {
106 			switch (flags & O_ACCMODE) {
107 			case O_RDONLY:
108 				sflags |= SHF_RD;
109 				break;
110 			case O_WRONLY:
111 				sflags |= SHF_WR;
112 				break;
113 			case O_RDWR:
114 				sflags |= SHF_RDWR;
115 				break;
116 			}
117 		}
118 		*sflagsp = sflags;
119 	}
120 
121 	if (!(sflags & (SHF_RD | SHF_WR)))
122 		internal_errorf("%s: %s", where, "missing read/write");
123 }
124 
125 /* Set up the shf structure for a file descriptor. Doesn't fail. */
126 struct shf *
shf_fdopen(int fd,int sflags,struct shf * shf)127 shf_fdopen(int fd, int sflags, struct shf *shf)
128 {
129 	ssize_t bsize =
130 	    /* at most 512 */
131 	    sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE;
132 
133 	shf_open_hlp(fd, &sflags, "shf_fdopen");
134 	if (shf) {
135 		if (bsize) {
136 			shf->buf = alloc(bsize, ATEMP);
137 			sflags |= SHF_ALLOCB;
138 		} else
139 			shf->buf = NULL;
140 	} else {
141 		shf = alloc(sizeof(struct shf) + bsize, ATEMP);
142 		shf->buf = (unsigned char *)&shf[1];
143 		sflags |= SHF_ALLOCS;
144 	}
145 	shf->areap = ATEMP;
146 	shf->fd = fd;
147 	shf->rp = shf->wp = shf->buf;
148 	shf->rnleft = 0;
149 	shf->rbsize = bsize;
150 	shf->wnleft = 0; /* force call to shf_emptybuf() */
151 	shf->wbsize = sflags & SHF_UNBUF ? 0 : bsize;
152 	shf->flags = sflags;
153 	shf->errnosv = 0;
154 	shf->bsize = bsize;
155 	if (sflags & SHF_CLEXEC)
156 		fcntl(fd, F_SETFD, FD_CLOEXEC);
157 	return (shf);
158 }
159 
160 /* Set up an existing shf (and buffer) to use the given fd */
161 struct shf *
shf_reopen(int fd,int sflags,struct shf * shf)162 shf_reopen(int fd, int sflags, struct shf *shf)
163 {
164 	ssize_t bsize =
165 	    /* at most 512 */
166 	    sflags & SHF_UNBUF ? (sflags & SHF_RD ? 1 : 0) : SHF_BSIZE;
167 
168 	shf_open_hlp(fd, &sflags, "shf_reopen");
169 	if (!shf || !shf->buf || shf->bsize < bsize)
170 		internal_errorf("%s: %s", "shf_reopen", "bad shf/buf/bsize");
171 
172 	/* assumes shf->buf and shf->bsize already set up */
173 	shf->fd = fd;
174 	shf->rp = shf->wp = shf->buf;
175 	shf->rnleft = 0;
176 	shf->rbsize = bsize;
177 	shf->wnleft = 0; /* force call to shf_emptybuf() */
178 	shf->wbsize = sflags & SHF_UNBUF ? 0 : bsize;
179 	shf->flags = (shf->flags & (SHF_ALLOCS | SHF_ALLOCB)) | sflags;
180 	shf->errnosv = 0;
181 	if (sflags & SHF_CLEXEC)
182 		fcntl(fd, F_SETFD, FD_CLOEXEC);
183 	return (shf);
184 }
185 
186 /*
187  * Open a string for reading or writing. If reading, bsize is the number
188  * of bytes that can be read. If writing, bsize is the maximum number of
189  * bytes that can be written. If shf is not NULL, it is filled in and
190  * returned, if it is NULL, shf is allocated. If writing and buf is NULL
191  * and SHF_DYNAMIC is set, the buffer is allocated (if bsize > 0, it is
192  * used for the initial size). Doesn't fail.
193  * When writing, a byte is reserved for a trailing NUL - see shf_sclose().
194  */
195 struct shf *
shf_sopen(char * buf,ssize_t bsize,int sflags,struct shf * shf)196 shf_sopen(char *buf, ssize_t bsize, int sflags, struct shf *shf)
197 {
198 	/* can't have a read+write string */
199 	if (!(!(sflags & SHF_RD) ^ !(sflags & SHF_WR)))
200 		internal_errorf("%s: flags 0x%X", "shf_sopen", sflags);
201 
202 	if (!shf) {
203 		shf = alloc(sizeof(struct shf), ATEMP);
204 		sflags |= SHF_ALLOCS;
205 	}
206 	shf->areap = ATEMP;
207 	if (!buf && (sflags & SHF_WR) && (sflags & SHF_DYNAMIC)) {
208 		if (bsize <= 0)
209 			bsize = 64;
210 		sflags |= SHF_ALLOCB;
211 		buf = alloc(bsize, shf->areap);
212 	}
213 	shf->fd = -1;
214 	shf->buf = shf->rp = shf->wp = (unsigned char *)buf;
215 	shf->rnleft = bsize;
216 	shf->rbsize = bsize;
217 	shf->wnleft = bsize - 1;	/* space for a '\0' */
218 	shf->wbsize = bsize;
219 	shf->flags = sflags | SHF_STRING;
220 	shf->errnosv = 0;
221 	shf->bsize = bsize;
222 
223 	return (shf);
224 }
225 
226 /* Flush and close file descriptor, free the shf structure */
227 int
shf_close(struct shf * shf)228 shf_close(struct shf *shf)
229 {
230 	int ret = 0;
231 
232 	if (shf->fd >= 0) {
233 		ret = shf_flush(shf);
234 		if (close(shf->fd) < 0)
235 			ret = -1;
236 	}
237 	if (shf->flags & SHF_ALLOCS)
238 		afree(shf, shf->areap);
239 	else if (shf->flags & SHF_ALLOCB)
240 		afree(shf->buf, shf->areap);
241 
242 	return (ret);
243 }
244 
245 /* Flush and close file descriptor, don't free file structure */
246 int
shf_fdclose(struct shf * shf)247 shf_fdclose(struct shf *shf)
248 {
249 	int ret = 0;
250 
251 	if (shf->fd >= 0) {
252 		ret = shf_flush(shf);
253 		if (close(shf->fd) < 0)
254 			ret = -1;
255 		shf->rnleft = 0;
256 		shf->rp = shf->buf;
257 		shf->wnleft = 0;
258 		shf->fd = -1;
259 	}
260 
261 	return (ret);
262 }
263 
264 /*
265  * Close a string - if it was opened for writing, it is NUL terminated;
266  * returns a pointer to the string and frees shf if it was allocated
267  * (does not free string if it was allocated).
268  */
269 char *
shf_sclose(struct shf * shf)270 shf_sclose(struct shf *shf)
271 {
272 	unsigned char *s = shf->buf;
273 
274 	/* NUL terminate */
275 	if (shf->flags & SHF_WR) {
276 		shf->wnleft++;
277 		shf_putc('\0', shf);
278 	}
279 	if (shf->flags & SHF_ALLOCS)
280 		afree(shf, shf->areap);
281 	return ((char *)s);
282 }
283 
284 /*
285  * Un-read what has been read but not examined, or write what has been
286  * buffered. Returns 0 for success, -1 for (write) error.
287  */
288 int
shf_flush(struct shf * shf)289 shf_flush(struct shf *shf)
290 {
291 	if (shf->flags & SHF_STRING)
292 		return ((shf->flags & SHF_WR) ? -1 : 0);
293 
294 	if (shf->fd < 0)
295 		internal_errorf("%s: %s", "shf_flush", "no fd");
296 
297 	if (shf->flags & SHF_ERROR) {
298 		errno = shf->errnosv;
299 		return (-1);
300 	}
301 
302 	if (shf->flags & SHF_READING) {
303 		shf->flags &= ~(SHF_EOF | SHF_READING);
304 		if (shf->rnleft > 0) {
305 			lseek(shf->fd, (off_t)-shf->rnleft, SEEK_CUR);
306 			shf->rnleft = 0;
307 			shf->rp = shf->buf;
308 		}
309 		return (0);
310 	} else if (shf->flags & SHF_WRITING)
311 		return (shf_emptybuf(shf, 0));
312 
313 	return (0);
314 }
315 
316 /*
317  * Write out any buffered data. If currently reading, flushes the read
318  * buffer. Returns 0 for success, -1 for (write) error.
319  */
320 static int
shf_emptybuf(struct shf * shf,int flags)321 shf_emptybuf(struct shf *shf, int flags)
322 {
323 	int ret = 0;
324 
325 	if (!(shf->flags & SHF_STRING) && shf->fd < 0)
326 		internal_errorf("%s: %s", "shf_emptybuf", "no fd");
327 
328 	if (shf->flags & SHF_ERROR) {
329 		errno = shf->errnosv;
330 		return (-1);
331 	}
332 
333 	if (shf->flags & SHF_READING) {
334 		if (flags & EB_READSW)
335 			/* doesn't happen */
336 			return (0);
337 		ret = shf_flush(shf);
338 		shf->flags &= ~SHF_READING;
339 	}
340 	if (shf->flags & SHF_STRING) {
341 		unsigned char *nbuf;
342 
343 		/*
344 		 * Note that we assume SHF_ALLOCS is not set if
345 		 * SHF_ALLOCB is set... (changing the shf pointer could
346 		 * cause problems)
347 		 */
348 		if (!(flags & EB_GROW) || !(shf->flags & SHF_DYNAMIC) ||
349 		    !(shf->flags & SHF_ALLOCB))
350 			return (-1);
351 		/* allocate more space for buffer */
352 		nbuf = aresize2(shf->buf, 2, shf->wbsize, shf->areap);
353 		shf->rp = nbuf + (shf->rp - shf->buf);
354 		shf->wp = nbuf + (shf->wp - shf->buf);
355 		shf->rbsize += shf->wbsize;
356 		shf->wnleft += shf->wbsize;
357 		shf->wbsize <<= 1;
358 		shf->buf = nbuf;
359 	} else {
360 		if (shf->flags & SHF_WRITING) {
361 			ssize_t n, ntowrite = shf->wp - shf->buf;
362 			unsigned char *buf = shf->buf;
363 
364 			while (ntowrite > 0) {
365 				n = write(shf->fd, buf, ntowrite);
366 				if (n < 0) {
367 					if (errno == EINTR &&
368 					    !(shf->flags & SHF_INTERRUPT))
369 						continue;
370 					shf->flags |= SHF_ERROR;
371 					shf->errnosv = errno;
372 					shf->wnleft = 0;
373 					if (buf != shf->buf) {
374 						/*
375 						 * allow a second flush
376 						 * to work
377 						 */
378 						memmove(shf->buf, buf,
379 						    ntowrite);
380 						shf->wp = shf->buf + ntowrite;
381 					}
382 					return (-1);
383 				}
384 				buf += n;
385 				ntowrite -= n;
386 			}
387 			if (flags & EB_READSW) {
388 				shf->wp = shf->buf;
389 				shf->wnleft = 0;
390 				shf->flags &= ~SHF_WRITING;
391 				return (0);
392 			}
393 		}
394 		shf->wp = shf->buf;
395 		shf->wnleft = shf->wbsize;
396 	}
397 	shf->flags |= SHF_WRITING;
398 
399 	return (ret);
400 }
401 
402 /* Fill up a read buffer. Returns -1 for a read error, 0 otherwise. */
403 static int
shf_fillbuf(struct shf * shf)404 shf_fillbuf(struct shf *shf)
405 {
406 	ssize_t n;
407 
408 	if (shf->flags & SHF_STRING)
409 		return (0);
410 
411 	if (shf->fd < 0)
412 		internal_errorf("%s: %s", "shf_fillbuf", "no fd");
413 
414 	if (shf->flags & (SHF_EOF | SHF_ERROR)) {
415 		if (shf->flags & SHF_ERROR)
416 			errno = shf->errnosv;
417 		return (-1);
418 	}
419 
420 	if ((shf->flags & SHF_WRITING) && shf_emptybuf(shf, EB_READSW) == -1)
421 		return (-1);
422 
423 	shf->flags |= SHF_READING;
424 
425 	shf->rp = shf->buf;
426 	while (/* CONSTCOND */ 1) {
427 		n = blocking_read(shf->fd, (char *)shf->buf, shf->rbsize);
428 		if (n < 0 && errno == EINTR && !(shf->flags & SHF_INTERRUPT))
429 			continue;
430 		break;
431 	}
432 	if (n < 0) {
433 		shf->flags |= SHF_ERROR;
434 		shf->errnosv = errno;
435 		shf->rnleft = 0;
436 		shf->rp = shf->buf;
437 		return (-1);
438 	}
439 	if ((shf->rnleft = n) == 0)
440 		shf->flags |= SHF_EOF;
441 	return (0);
442 }
443 
444 /*
445  * Read a buffer from shf. Returns the number of bytes read into buf, if
446  * no bytes were read, returns 0 if end of file was seen, -1 if a read
447  * error occurred.
448  */
449 ssize_t
shf_read(char * buf,ssize_t bsize,struct shf * shf)450 shf_read(char *buf, ssize_t bsize, struct shf *shf)
451 {
452 	ssize_t ncopy, orig_bsize = bsize;
453 
454 	if (!(shf->flags & SHF_RD))
455 		internal_errorf("%s: flags 0x%X", "shf_read", shf->flags);
456 
457 	if (bsize <= 0)
458 		internal_errorf("%s: %s %zd", "shf_write", "bsize", bsize);
459 
460 	while (bsize > 0) {
461 		if (shf->rnleft == 0 &&
462 		    (shf_fillbuf(shf) == -1 || shf->rnleft == 0))
463 			break;
464 		ncopy = shf->rnleft;
465 		if (ncopy > bsize)
466 			ncopy = bsize;
467 		memcpy(buf, shf->rp, ncopy);
468 		buf += ncopy;
469 		bsize -= ncopy;
470 		shf->rp += ncopy;
471 		shf->rnleft -= ncopy;
472 	}
473 	/* Note: fread(3S) returns 0 for errors - this doesn't */
474 	return (orig_bsize == bsize ? (shf_error(shf) ? -1 : 0) :
475 	    orig_bsize - bsize);
476 }
477 
478 /*
479  * Read up to a newline or -1. The newline is put in buf; buf is always
480  * NUL terminated. Returns NULL on read error or if nothing was read
481  * before end of file, returns a pointer to the NUL byte in buf
482  * otherwise.
483  */
484 char *
shf_getse(char * buf,ssize_t bsize,struct shf * shf)485 shf_getse(char *buf, ssize_t bsize, struct shf *shf)
486 {
487 	unsigned char *end;
488 	ssize_t ncopy;
489 	char *orig_buf = buf;
490 
491 	if (!(shf->flags & SHF_RD))
492 		internal_errorf("%s: flags 0x%X", "shf_getse", shf->flags);
493 
494 	if (bsize <= 0)
495 		return (NULL);
496 
497 	/* save room for NUL */
498 	--bsize;
499 	do {
500 		if (shf->rnleft == 0) {
501 			if (shf_fillbuf(shf) == -1)
502 				return (NULL);
503 			if (shf->rnleft == 0) {
504 				*buf = '\0';
505 				return (buf == orig_buf ? NULL : buf);
506 			}
507 		}
508 		end = (unsigned char *)memchr((char *)shf->rp, '\n',
509 		    shf->rnleft);
510 		ncopy = end ? end - shf->rp + 1 : shf->rnleft;
511 		if (ncopy > bsize)
512 			ncopy = bsize;
513 		memcpy(buf, (char *) shf->rp, ncopy);
514 		shf->rp += ncopy;
515 		shf->rnleft -= ncopy;
516 		buf += ncopy;
517 		bsize -= ncopy;
518 	} while (!end && bsize);
519 	*buf = '\0';
520 	return (buf);
521 }
522 
523 /* Returns the char read. Returns -1 for error and end of file. */
524 int
shf_getchar(struct shf * shf)525 shf_getchar(struct shf *shf)
526 {
527 	if (!(shf->flags & SHF_RD))
528 		internal_errorf("%s: flags 0x%X", "shf_getchar", shf->flags);
529 
530 	if (shf->rnleft == 0 && (shf_fillbuf(shf) == -1 || shf->rnleft == 0))
531 		return (-1);
532 	--shf->rnleft;
533 	return (*shf->rp++);
534 }
535 
536 /*
537  * Put a character back in the input stream. Returns the character if
538  * successful, -1 if there is no room.
539  */
540 int
shf_ungetc(int c,struct shf * shf)541 shf_ungetc(int c, struct shf *shf)
542 {
543 	if (!(shf->flags & SHF_RD))
544 		internal_errorf("%s: flags 0x%X", "shf_ungetc", shf->flags);
545 
546 	if ((shf->flags & SHF_ERROR) || c == -1 ||
547 	    (shf->rp == shf->buf && shf->rnleft))
548 		return (-1);
549 
550 	if ((shf->flags & SHF_WRITING) && shf_emptybuf(shf, EB_READSW) == -1)
551 		return (-1);
552 
553 	if (shf->rp == shf->buf)
554 		shf->rp = shf->buf + shf->rbsize;
555 	if (shf->flags & SHF_STRING) {
556 		/*
557 		 * Can unget what was read, but not something different;
558 		 * we don't want to modify a string.
559 		 */
560 		if ((int)(shf->rp[-1]) != c)
561 			return (-1);
562 		shf->flags &= ~SHF_EOF;
563 		shf->rp--;
564 		shf->rnleft++;
565 		return (c);
566 	}
567 	shf->flags &= ~SHF_EOF;
568 	*--(shf->rp) = c;
569 	shf->rnleft++;
570 	return (c);
571 }
572 
573 /*
574  * Write a character. Returns the character if successful, -1 if the
575  * char could not be written.
576  */
577 int
shf_putchar(int c,struct shf * shf)578 shf_putchar(int c, struct shf *shf)
579 {
580 	if (!(shf->flags & SHF_WR))
581 		internal_errorf("%s: flags 0x%X", "shf_putchar", shf->flags);
582 
583 	if (c == -1)
584 		return (-1);
585 
586 	if (shf->flags & SHF_UNBUF) {
587 		unsigned char cc = (unsigned char)c;
588 		ssize_t n;
589 
590 		if (shf->fd < 0)
591 			internal_errorf("%s: %s", "shf_putchar", "no fd");
592 		if (shf->flags & SHF_ERROR) {
593 			errno = shf->errnosv;
594 			return (-1);
595 		}
596 		while ((n = write(shf->fd, &cc, 1)) != 1)
597 			if (n < 0) {
598 				if (errno == EINTR &&
599 				    !(shf->flags & SHF_INTERRUPT))
600 					continue;
601 				shf->flags |= SHF_ERROR;
602 				shf->errnosv = errno;
603 				return (-1);
604 			}
605 	} else {
606 		/* Flush deals with strings and sticky errors */
607 		if (shf->wnleft == 0 && shf_emptybuf(shf, EB_GROW) == -1)
608 			return (-1);
609 		shf->wnleft--;
610 		*shf->wp++ = c;
611 	}
612 
613 	return (c);
614 }
615 
616 /*
617  * Write a string. Returns the length of the string if successful, -1
618  * if the string could not be written.
619  */
620 ssize_t
shf_puts(const char * s,struct shf * shf)621 shf_puts(const char *s, struct shf *shf)
622 {
623 	if (!s)
624 		return (-1);
625 
626 	return (shf_write(s, strlen(s), shf));
627 }
628 
629 /* Write a buffer. Returns nbytes if successful, -1 if there is an error. */
630 ssize_t
shf_write(const char * buf,ssize_t nbytes,struct shf * shf)631 shf_write(const char *buf, ssize_t nbytes, struct shf *shf)
632 {
633 	ssize_t n, ncopy, orig_nbytes = nbytes;
634 
635 	if (!(shf->flags & SHF_WR))
636 		internal_errorf("%s: flags 0x%X", "shf_write", shf->flags);
637 
638 	if (nbytes < 0)
639 		internal_errorf("%s: %s %zd", "shf_write", "nbytes", nbytes);
640 
641 	/* Don't buffer if buffer is empty and we're writting a large amount. */
642 	if ((ncopy = shf->wnleft) &&
643 	    (shf->wp != shf->buf || nbytes < shf->wnleft)) {
644 		if (ncopy > nbytes)
645 			ncopy = nbytes;
646 		memcpy(shf->wp, buf, ncopy);
647 		nbytes -= ncopy;
648 		buf += ncopy;
649 		shf->wp += ncopy;
650 		shf->wnleft -= ncopy;
651 	}
652 	if (nbytes > 0) {
653 		if (shf->flags & SHF_STRING) {
654 			/* resize buffer until there's enough space left */
655 			while (nbytes > shf->wnleft)
656 				if (shf_emptybuf(shf, EB_GROW) == -1)
657 					return (-1);
658 			/* then write everything into the buffer */
659 		} else {
660 			/* flush deals with sticky errors */
661 			if (shf_emptybuf(shf, EB_GROW) == -1)
662 				return (-1);
663 			/* write chunks larger than window size directly */
664 			if (nbytes > shf->wbsize) {
665 				ncopy = nbytes;
666 				if (shf->wbsize)
667 					ncopy -= nbytes % shf->wbsize;
668 				nbytes -= ncopy;
669 				while (ncopy > 0) {
670 					n = write(shf->fd, buf, ncopy);
671 					if (n < 0) {
672 						if (errno == EINTR &&
673 						    !(shf->flags & SHF_INTERRUPT))
674 							continue;
675 						shf->flags |= SHF_ERROR;
676 						shf->errnosv = errno;
677 						shf->wnleft = 0;
678 						/*
679 						 * Note: fwrite(3) returns 0
680 						 * for errors - this doesn't
681 						 */
682 						return (-1);
683 					}
684 					buf += n;
685 					ncopy -= n;
686 				}
687 			}
688 			/* ... and buffer the rest */
689 		}
690 		if (nbytes > 0) {
691 			/* write remaining bytes to buffer */
692 			memcpy(shf->wp, buf, nbytes);
693 			shf->wp += nbytes;
694 			shf->wnleft -= nbytes;
695 		}
696 	}
697 
698 	return (orig_nbytes);
699 }
700 
701 ssize_t
shf_fprintf(struct shf * shf,const char * fmt,...)702 shf_fprintf(struct shf *shf, const char *fmt, ...)
703 {
704 	va_list args;
705 	ssize_t n;
706 
707 	va_start(args, fmt);
708 	n = shf_vfprintf(shf, fmt, args);
709 	va_end(args);
710 
711 	return (n);
712 }
713 
714 ssize_t
shf_snprintf(char * buf,ssize_t bsize,const char * fmt,...)715 shf_snprintf(char *buf, ssize_t bsize, const char *fmt, ...)
716 {
717 	struct shf shf;
718 	va_list args;
719 	ssize_t n;
720 
721 	if (!buf || bsize <= 0)
722 		internal_errorf("shf_snprintf: buf %zX, bsize %zd",
723 		    (size_t)buf, bsize);
724 
725 	shf_sopen(buf, bsize, SHF_WR, &shf);
726 	va_start(args, fmt);
727 	n = shf_vfprintf(&shf, fmt, args);
728 	va_end(args);
729 	/* NUL terminates */
730 	shf_sclose(&shf);
731 	return (n);
732 }
733 
734 char *
shf_smprintf(const char * fmt,...)735 shf_smprintf(const char *fmt, ...)
736 {
737 	struct shf shf;
738 	va_list args;
739 
740 	shf_sopen(NULL, 0, SHF_WR|SHF_DYNAMIC, &shf);
741 	va_start(args, fmt);
742 	shf_vfprintf(&shf, fmt, args);
743 	va_end(args);
744 	/* NUL terminates */
745 	return (shf_sclose(&shf));
746 }
747 
748 #define	FL_HASH		0x001	/* '#' seen */
749 #define FL_PLUS		0x002	/* '+' seen */
750 #define FL_RIGHT	0x004	/* '-' seen */
751 #define FL_BLANK	0x008	/* ' ' seen */
752 #define FL_SHORT	0x010	/* 'h' seen */
753 #define FL_LONG		0x020	/* 'l' seen */
754 #define FL_ZERO		0x040	/* '0' seen */
755 #define FL_DOT		0x080	/* '.' seen */
756 #define FL_UPPER	0x100	/* format character was uppercase */
757 #define FL_NUMBER	0x200	/* a number was formated %[douxefg] */
758 #define FL_SIZET	0x400	/* 'z' seen */
759 #define FM_SIZES	0x430	/* h/l/z mask */
760 
761 ssize_t
shf_vfprintf(struct shf * shf,const char * fmt,va_list args)762 shf_vfprintf(struct shf *shf, const char *fmt, va_list args)
763 {
764 	const char *s;
765 	char c, *cp;
766 	int tmp = 0, flags;
767 	ssize_t field, precision, len;
768 	unsigned long lnum;
769 	/* %#o produces the longest output */
770 	char numbuf[(8 * sizeof(long) + 2) / 3 + 1];
771 	/* this stuff for dealing with the buffer */
772 	ssize_t nwritten = 0;
773 
774 #define VA(type) va_arg(args, type)
775 
776 	if (!fmt)
777 		return (0);
778 
779 	while ((c = *fmt++)) {
780 		if (c != '%') {
781 			shf_putc(c, shf);
782 			nwritten++;
783 			continue;
784 		}
785 		/*
786 		 * This will accept flags/fields in any order - not just
787 		 * the order specified in printf(3), but this is the way
788 		 * _doprnt() seems to work (on BSD and SYSV). The only
789 		 * restriction is that the format character must come
790 		 * last :-).
791 		 */
792 		flags = 0;
793 		field = precision = 0;
794 		for ( ; (c = *fmt++) ; ) {
795 			switch (c) {
796 			case '#':
797 				flags |= FL_HASH;
798 				continue;
799 
800 			case '+':
801 				flags |= FL_PLUS;
802 				continue;
803 
804 			case '-':
805 				flags |= FL_RIGHT;
806 				continue;
807 
808 			case ' ':
809 				flags |= FL_BLANK;
810 				continue;
811 
812 			case '0':
813 				if (!(flags & FL_DOT))
814 					flags |= FL_ZERO;
815 				continue;
816 
817 			case '.':
818 				flags |= FL_DOT;
819 				precision = 0;
820 				continue;
821 
822 			case '*':
823 				tmp = VA(int);
824 				if (flags & FL_DOT)
825 					precision = tmp;
826 				else if ((field = tmp) < 0) {
827 					field = -field;
828 					flags |= FL_RIGHT;
829 				}
830 				continue;
831 
832 			case 'l':
833 				flags &= ~FM_SIZES;
834 				flags |= FL_LONG;
835 				continue;
836 
837 			case 'h':
838 				flags &= ~FM_SIZES;
839 				flags |= FL_SHORT;
840 				continue;
841 
842 			case 'z':
843 				flags &= ~FM_SIZES;
844 				flags |= FL_SIZET;
845 				continue;
846 			}
847 			if (ksh_isdigit(c)) {
848 				bool overflowed = false;
849 
850 				tmp = ksh_numdig(c);
851 				while (c = *fmt++, ksh_isdigit(c)) {
852 					if (notok2mul(2147483647, tmp, 10))
853 						overflowed = true;
854 					tmp = tmp * 10 + ksh_numdig(c);
855 				}
856 				--fmt;
857 				if (overflowed)
858 					tmp = 0;
859 				if (flags & FL_DOT)
860 					precision = tmp;
861 				else
862 					field = tmp;
863 				continue;
864 			}
865 			break;
866 		}
867 
868 		if (precision < 0)
869 			precision = 0;
870 
871 		if (!c)
872 			/* nasty format */
873 			break;
874 
875 		if (ksh_isupper(c)) {
876 			flags |= FL_UPPER;
877 			c = ksh_tolower(c);
878 		}
879 
880 		switch (c) {
881 		case 'd':
882 		case 'i':
883 			if (flags & FL_SIZET)
884 				lnum = (long)VA(ssize_t);
885 			else if (flags & FL_LONG)
886 				lnum = VA(long);
887 			else if (flags & FL_SHORT)
888 				lnum = (long)(short)VA(int);
889 			else
890 				lnum = (long)VA(int);
891 			goto integral;
892 
893 		case 'o':
894 		case 'u':
895 		case 'x':
896 			if (flags & FL_SIZET)
897 				lnum = VA(size_t);
898 			else if (flags & FL_LONG)
899 				lnum = VA(unsigned long);
900 			else if (flags & FL_SHORT)
901 				lnum = (unsigned long)(unsigned short)VA(int);
902 			else
903 				lnum = (unsigned long)VA(unsigned int);
904 
905  integral:
906 			flags |= FL_NUMBER;
907 			cp = numbuf + sizeof(numbuf);
908 
909 			switch (c) {
910 			case 'd':
911 			case 'i':
912 				if (0 > (long)lnum) {
913 					lnum = -(long)lnum;
914 					tmp = 1;
915 				} else
916 					tmp = 0;
917 				/* FALLTHROUGH */
918 			case 'u':
919 				do {
920 					*--cp = digits_lc[lnum % 10];
921 					lnum /= 10;
922 				} while (lnum);
923 
924 				if (c != 'u') {
925 					if (tmp)
926 						*--cp = '-';
927 					else if (flags & FL_PLUS)
928 						*--cp = '+';
929 					else if (flags & FL_BLANK)
930 						*--cp = ' ';
931 				}
932 				break;
933 
934 			case 'o':
935 				do {
936 					*--cp = digits_lc[lnum & 0x7];
937 					lnum >>= 3;
938 				} while (lnum);
939 
940 				if ((flags & FL_HASH) && *cp != '0')
941 					*--cp = '0';
942 				break;
943 
944 			case 'x': {
945 				const char *digits = (flags & FL_UPPER) ?
946 				    digits_uc : digits_lc;
947 				do {
948 					*--cp = digits[lnum & 0xF];
949 					lnum >>= 4;
950 				} while (lnum);
951 
952 				if (flags & FL_HASH) {
953 					*--cp = (flags & FL_UPPER) ? 'X' : 'x';
954 					*--cp = '0';
955 				}
956 			}
957 			}
958 			len = numbuf + sizeof(numbuf) - (s = cp);
959 			if (flags & FL_DOT) {
960 				if (precision > len) {
961 					field = precision;
962 					flags |= FL_ZERO;
963 				} else
964 					/* no loss */
965 					precision = len;
966 			}
967 			break;
968 
969 		case 's':
970 			if ((s = VA(const char *)) == NULL)
971 				s = "(null)";
972 			else if (flags & FL_HASH) {
973 				print_value_quoted(shf, s);
974 				continue;
975 			}
976 			len = utf_mbswidth(s);
977 			break;
978 
979 		case 'c':
980 			flags &= ~FL_DOT;
981 			c = (char)(VA(int));
982 			/* FALLTHROUGH */
983 
984 		case '%':
985 		default:
986 			numbuf[0] = c;
987 			numbuf[1] = 0;
988 			s = numbuf;
989 			len = 1;
990 			break;
991 		}
992 
993 		/*
994 		 * At this point s should point to a string that is to be
995 		 * formatted, and len should be the length of the string.
996 		 */
997 		if (!(flags & FL_DOT) || len < precision)
998 			precision = len;
999 		if (field > precision) {
1000 			field -= precision;
1001 			if (!(flags & FL_RIGHT)) {
1002 				field = -field;
1003 				/* skip past sign or 0x when padding with 0 */
1004 				if ((flags & FL_ZERO) && (flags & FL_NUMBER)) {
1005 					if (*s == '+' || *s == '-' ||
1006 					    *s == ' ') {
1007 						shf_putc(*s, shf);
1008 						s++;
1009 						precision--;
1010 						nwritten++;
1011 					} else if (*s == '0') {
1012 						shf_putc(*s, shf);
1013 						s++;
1014 						nwritten++;
1015 						if (--precision > 0 &&
1016 						    ksh_eq(*s, 'X', 'x')) {
1017 							shf_putc(*s, shf);
1018 							s++;
1019 							precision--;
1020 							nwritten++;
1021 						}
1022 					}
1023 					c = '0';
1024 				} else
1025 					c = flags & FL_ZERO ? '0' : ' ';
1026 				if (field < 0) {
1027 					nwritten += -field;
1028 					while (field < 0) {
1029 						shf_putc(c, shf);
1030 						++field;
1031 					}
1032 				}
1033 			} else
1034 				c = ' ';
1035 		} else
1036 			field = 0;
1037 
1038 		if (precision > 0) {
1039 			const char *q;
1040 
1041 			nwritten += precision;
1042 			q = utf_skipcols(s, precision);
1043 			do {
1044 				shf_putc(*s, shf);
1045 			} while (++s < q);
1046 		}
1047 		if (field > 0) {
1048 			nwritten += field;
1049 			for ( ; field > 0 ; --field)
1050 				shf_putc(c, shf);
1051 		}
1052 	}
1053 
1054 	return (shf_error(shf) ? -1 : nwritten);
1055 }
1056 
1057 #if defined(MKSH_SMALL) && !defined(MKSH_SMALL_BUT_FAST)
1058 int
shf_getc(struct shf * shf)1059 shf_getc(struct shf *shf)
1060 {
1061 	return (shf_getc_i(shf));
1062 }
1063 
1064 int
shf_putc(int c,struct shf * shf)1065 shf_putc(int c, struct shf *shf)
1066 {
1067 	return (shf_putc_i(c, shf));
1068 }
1069 #endif
1070 
1071 #ifdef DEBUG
1072 const char *
cstrerror(int errnum)1073 cstrerror(int errnum)
1074 {
1075 #undef strerror
1076 	return (strerror(errnum));
1077 #define strerror dontuse_strerror /* poisoned */
1078 }
1079 #elif !HAVE_STRERROR
1080 
1081 #if HAVE_SYS_ERRLIST
1082 #if !HAVE_SYS_ERRLIST_DECL
1083 extern const int sys_nerr;
1084 extern const char * const sys_errlist[];
1085 #endif
1086 #endif
1087 
1088 const char *
cstrerror(int errnum)1089 cstrerror(int errnum)
1090 {
1091 	/* "Unknown error: " + sign + rough estimate + NUL */
1092 	static char errbuf[15 + 1 + (8 * sizeof(int) + 2) / 3 + 1];
1093 
1094 #if HAVE_SYS_ERRLIST
1095 	if (errnum > 0 && errnum < sys_nerr && sys_errlist[errnum])
1096 		return (sys_errlist[errnum]);
1097 #endif
1098 
1099 	switch (errnum) {
1100 	case 0:
1101 		return ("Undefined error: 0");
1102 	case EPERM:
1103 		return ("Operation not permitted");
1104 	case ENOENT:
1105 		return ("No such file or directory");
1106 #ifdef ESRCH
1107 	case ESRCH:
1108 		return ("No such process");
1109 #endif
1110 #ifdef E2BIG
1111 	case E2BIG:
1112 		return ("Argument list too long");
1113 #endif
1114 	case ENOEXEC:
1115 		return ("Exec format error");
1116 	case EBADF:
1117 		return ("Bad file descriptor");
1118 #ifdef ENOMEM
1119 	case ENOMEM:
1120 		return ("Cannot allocate memory");
1121 #endif
1122 	case EACCES:
1123 		return ("Permission denied");
1124 	case EEXIST:
1125 		return ("File exists");
1126 	case ENOTDIR:
1127 		return ("Not a directory");
1128 #ifdef EINVAL
1129 	case EINVAL:
1130 		return ("Invalid argument");
1131 #endif
1132 #ifdef ELOOP
1133 	case ELOOP:
1134 		return ("Too many levels of symbolic links");
1135 #endif
1136 	default:
1137 		shf_snprintf(errbuf, sizeof(errbuf),
1138 		    "Unknown error: %d", errnum);
1139 		return (errbuf);
1140 	}
1141 }
1142 #endif
1143