xref: /freebsd/usr.bin/grep/util.c (revision c685956956793831f724177309eace82c4b347b9)
1 /*	$NetBSD: util.c,v 1.9 2011/02/27 17:33:37 joerg Exp $	*/
2 /*	$FreeBSD$	*/
3 /*	$OpenBSD: util.c,v 1.39 2010/07/02 22:18:03 tedu Exp $	*/
4 
5 /*-
6  * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
7  * Copyright (C) 2008-2010 Gabor Kovesdan <gabor@FreeBSD.org>
8  * Copyright (C) 2017 Kyle Evans <kevans@FreeBSD.org>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/stat.h>
37 #include <sys/types.h>
38 
39 #include <ctype.h>
40 #include <err.h>
41 #include <errno.h>
42 #include <fnmatch.h>
43 #include <fts.h>
44 #include <libgen.h>
45 #include <stdbool.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #include <wchar.h>
51 #include <wctype.h>
52 
53 #ifndef WITHOUT_FASTMATCH
54 #include "fastmatch.h"
55 #endif
56 #include "grep.h"
57 
58 static bool	 first_match = true;
59 
60 /*
61  * Parsing context; used to hold things like matches made and
62  * other useful bits
63  */
64 struct parsec {
65 	regmatch_t	matches[MAX_MATCHES];		/* Matches made */
66 	struct str	ln;				/* Current line */
67 	size_t		lnstart;			/* Position in line */
68 	size_t		matchidx;			/* Latest match index */
69 	int		printed;			/* Metadata printed? */
70 	bool		binary;				/* Binary file? */
71 };
72 
73 
74 static int procline(struct parsec *pc);
75 static void printline(struct parsec *pc, int sep);
76 static void printline_metadata(struct str *line, int sep);
77 
78 bool
79 file_matching(const char *fname)
80 {
81 	char *fname_base, *fname_buf;
82 	bool ret;
83 
84 	ret = finclude ? false : true;
85 	fname_buf = strdup(fname);
86 	if (fname_buf == NULL)
87 		err(2, "strdup");
88 	fname_base = basename(fname_buf);
89 
90 	for (unsigned int i = 0; i < fpatterns; ++i) {
91 		if (fnmatch(fpattern[i].pat, fname, 0) == 0 ||
92 		    fnmatch(fpattern[i].pat, fname_base, 0) == 0) {
93 			if (fpattern[i].mode == EXCL_PAT) {
94 				ret = false;
95 				break;
96 			} else
97 				ret = true;
98 		}
99 	}
100 	free(fname_buf);
101 	return (ret);
102 }
103 
104 static inline bool
105 dir_matching(const char *dname)
106 {
107 	bool ret;
108 
109 	ret = dinclude ? false : true;
110 
111 	for (unsigned int i = 0; i < dpatterns; ++i) {
112 		if (dname != NULL &&
113 		    fnmatch(dpattern[i].pat, dname, 0) == 0) {
114 			if (dpattern[i].mode == EXCL_PAT)
115 				return (false);
116 			else
117 				ret = true;
118 		}
119 	}
120 	return (ret);
121 }
122 
123 /*
124  * Processes a directory when a recursive search is performed with
125  * the -R option.  Each appropriate file is passed to procfile().
126  */
127 int
128 grep_tree(char **argv)
129 {
130 	FTS *fts;
131 	FTSENT *p;
132 	int c, fts_flags;
133 	bool ok;
134 	const char *wd[] = { ".", NULL };
135 
136 	c = fts_flags = 0;
137 
138 	switch(linkbehave) {
139 	case LINK_EXPLICIT:
140 		fts_flags = FTS_COMFOLLOW;
141 		break;
142 	case LINK_SKIP:
143 		fts_flags = FTS_PHYSICAL;
144 		break;
145 	default:
146 		fts_flags = FTS_LOGICAL;
147 
148 	}
149 
150 	fts_flags |= FTS_NOSTAT | FTS_NOCHDIR;
151 
152 	fts = fts_open((argv[0] == NULL) ?
153 	    __DECONST(char * const *, wd) : argv, fts_flags, NULL);
154 	if (fts == NULL)
155 		err(2, "fts_open");
156 	while ((p = fts_read(fts)) != NULL) {
157 		switch (p->fts_info) {
158 		case FTS_DNR:
159 			/* FALLTHROUGH */
160 		case FTS_ERR:
161 			file_err = true;
162 			if(!sflag)
163 				warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
164 			break;
165 		case FTS_D:
166 			/* FALLTHROUGH */
167 		case FTS_DP:
168 			if (dexclude || dinclude)
169 				if (!dir_matching(p->fts_name) ||
170 				    !dir_matching(p->fts_path))
171 					fts_set(fts, p, FTS_SKIP);
172 			break;
173 		case FTS_DC:
174 			/* Print a warning for recursive directory loop */
175 			warnx("warning: %s: recursive directory loop",
176 				p->fts_path);
177 			break;
178 		default:
179 			/* Check for file exclusion/inclusion */
180 			ok = true;
181 			if (fexclude || finclude)
182 				ok &= file_matching(p->fts_path);
183 
184 			if (ok)
185 				c += procfile(p->fts_path);
186 			break;
187 		}
188 	}
189 
190 	fts_close(fts);
191 	return (c);
192 }
193 
194 /*
195  * Opens a file and processes it.  Each file is processed line-by-line
196  * passing the lines to procline().
197  */
198 int
199 procfile(const char *fn)
200 {
201 	struct parsec pc;
202 	long long tail;
203 	struct file *f;
204 	struct stat sb;
205 	struct str *ln;
206 	mode_t s;
207 	int c, last_outed, t;
208 	bool doctx, printmatch, same_file;
209 
210 	if (strcmp(fn, "-") == 0) {
211 		fn = label != NULL ? label : getstr(1);
212 		f = grep_open(NULL);
213 	} else {
214 		if (!stat(fn, &sb)) {
215 			/* Check if we need to process the file */
216 			s = sb.st_mode & S_IFMT;
217 			if (s == S_IFDIR && dirbehave == DIR_SKIP)
218 				return (0);
219 			if ((s == S_IFIFO || s == S_IFCHR || s == S_IFBLK
220 				|| s == S_IFSOCK) && devbehave == DEV_SKIP)
221 					return (0);
222 		}
223 		f = grep_open(fn);
224 	}
225 	if (f == NULL) {
226 		file_err = true;
227 		if (!sflag)
228 			warn("%s", fn);
229 		return (0);
230 	}
231 
232 	/* Convenience */
233 	ln = &pc.ln;
234 	pc.ln.file = grep_malloc(strlen(fn) + 1);
235 	strcpy(pc.ln.file, fn);
236 	pc.ln.line_no = 0;
237 	pc.ln.len = 0;
238 	pc.ln.boff = 0;
239 	pc.ln.off = -1;
240 	pc.binary = f->binary;
241 	pc.printed = 0;
242 	tail = 0;
243 	last_outed = 0;
244 	same_file = false;
245 	doctx = false;
246 	printmatch = true;
247 	if ((pc.binary && binbehave == BINFILE_BIN) || cflag || qflag ||
248 	    lflag || Lflag)
249 		printmatch = false;
250 	if (printmatch && (Aflag != 0 || Bflag != 0))
251 		doctx = true;
252 	mcount = mlimit;
253 
254 	for (c = 0;  c == 0 || !(lflag || qflag); ) {
255 		/* Reset per-line statistics */
256 		pc.printed = 0;
257 		pc.matchidx = 0;
258 		pc.lnstart = 0;
259 		pc.ln.boff = 0;
260 		pc.ln.off += pc.ln.len + 1;
261 		if ((pc.ln.dat = grep_fgetln(f, &pc.ln.len)) == NULL ||
262 		    pc.ln.len == 0)
263 			break;
264 
265 		if (pc.ln.len > 0 && pc.ln.dat[pc.ln.len - 1] == fileeol)
266 			--pc.ln.len;
267 		pc.ln.line_no++;
268 
269 		/* Return if we need to skip a binary file */
270 		if (pc.binary && binbehave == BINFILE_SKIP) {
271 			grep_close(f);
272 			free(pc.ln.file);
273 			free(f);
274 			return (0);
275 		}
276 
277 		if ((t = procline(&pc)) == 0)
278 			++c;
279 
280 		/* Deal with any -B context or context separators */
281 		if (t == 0 && doctx) {
282 			if (!first_match && (!same_file || last_outed > 0))
283 				printf("--\n");
284 			if (Bflag > 0)
285 				printqueue();
286 			tail = Aflag;
287 		}
288 		/* Print the matching line, but only if not quiet/binary */
289 		if (t == 0 && printmatch) {
290 			printline(&pc, ':');
291 			while (pc.matchidx >= MAX_MATCHES) {
292 				/* Reset matchidx and try again */
293 				pc.matchidx = 0;
294 				if (procline(&pc) == 0)
295 					printline(&pc, ':');
296 				else
297 					break;
298 			}
299 			first_match = false;
300 			same_file = true;
301 			last_outed = 0;
302 		}
303 		if (t != 0 && doctx) {
304 			/* Deal with any -A context */
305 			if (tail > 0) {
306 				grep_printline(&pc.ln, '-');
307 				tail--;
308 				if (Bflag > 0)
309 					clearqueue();
310 			} else {
311 				/*
312 				 * Enqueue non-matching lines for -B context.
313 				 * If we're not actually doing -B context or if
314 				 * the enqueue resulted in a line being rotated
315 				 * out, then go ahead and increment last_outed
316 				 * to signify a gap between context/match.
317 				 */
318 				if (Bflag == 0 || (Bflag > 0 && enqueue(ln)))
319 					++last_outed;
320 			}
321 		}
322 
323 		/* Count the matches if we have a match limit */
324 		if (t == 0 && mflag) {
325 			--mcount;
326 			if (mflag && mcount <= 0)
327 				break;
328 		}
329 
330 	}
331 	if (Bflag > 0)
332 		clearqueue();
333 	grep_close(f);
334 
335 	if (cflag) {
336 		if (!hflag)
337 			printf("%s:", pc.ln.file);
338 		printf("%u\n", c);
339 	}
340 	if (lflag && !qflag && c != 0)
341 		printf("%s%c", fn, nullflag ? 0 : '\n');
342 	if (Lflag && !qflag && c == 0)
343 		printf("%s%c", fn, nullflag ? 0 : '\n');
344 	if (c && !cflag && !lflag && !Lflag &&
345 	    binbehave == BINFILE_BIN && f->binary && !qflag)
346 		printf(getstr(8), fn);
347 
348 	free(pc.ln.file);
349 	free(f);
350 	return (c);
351 }
352 
353 #define iswword(x)	(iswalnum((x)) || (x) == L'_')
354 
355 /*
356  * Processes a line comparing it with the specified patterns.  Each pattern
357  * is looped to be compared along with the full string, saving each and every
358  * match, which is necessary to colorize the output and to count the
359  * matches.  The matching lines are passed to printline() to display the
360  * appropriate output.
361  */
362 static int
363 procline(struct parsec *pc)
364 {
365 	regmatch_t pmatch, lastmatch, chkmatch;
366 	wchar_t wbegin, wend;
367 	size_t st, nst;
368 	unsigned int i;
369 	int c = 0, r = 0, lastmatches = 0, leflags = eflags;
370 	size_t startm = 0, matchidx;
371 	unsigned int retry;
372 
373 	matchidx = pc->matchidx;
374 
375 	/* Special case: empty pattern with -w flag, check first character */
376 	if (matchall && wflag) {
377 		if (pc->ln.len == 0)
378 			return (0);
379 		wend = L' ';
380 		if (sscanf(&pc->ln.dat[0], "%lc", &wend) != 1 || iswword(wend))
381 			return (1);
382 		else
383 			return (0);
384 	} else if (matchall)
385 		return (0);
386 
387 	st = pc->lnstart;
388 	nst = 0;
389 	/* Initialize to avoid a false positive warning from GCC. */
390 	lastmatch.rm_so = lastmatch.rm_eo = 0;
391 
392 	/* Loop to process the whole line */
393 	while (st <= pc->ln.len) {
394 		lastmatches = 0;
395 		startm = matchidx;
396 		retry = 0;
397 		if (st > 0 && pc->ln.dat[st - 1] != fileeol)
398 			leflags |= REG_NOTBOL;
399 		/* Loop to compare with all the patterns */
400 		for (i = 0; i < patterns; i++) {
401 			pmatch.rm_so = st;
402 			pmatch.rm_eo = pc->ln.len;
403 #ifndef WITHOUT_FASTMATCH
404 			if (fg_pattern[i].pattern)
405 				r = fastexec(&fg_pattern[i],
406 				    pc->ln.dat, 1, &pmatch, leflags);
407 			else
408 #endif
409 				r = regexec(&r_pattern[i], pc->ln.dat, 1,
410 				    &pmatch, leflags);
411 			if (r != 0)
412 				continue;
413 			/* Check for full match */
414 			if (xflag && (pmatch.rm_so != 0 ||
415 			    (size_t)pmatch.rm_eo != pc->ln.len))
416 				continue;
417 			/* Check for whole word match */
418 #ifndef WITHOUT_FASTMATCH
419 			if (wflag || fg_pattern[i].word) {
420 #else
421 			if (wflag) {
422 #endif
423 				wbegin = wend = L' ';
424 				if (pmatch.rm_so != 0 &&
425 				    sscanf(&pc->ln.dat[pmatch.rm_so - 1],
426 				    "%lc", &wbegin) != 1)
427 					r = REG_NOMATCH;
428 				else if ((size_t)pmatch.rm_eo !=
429 				    pc->ln.len &&
430 				    sscanf(&pc->ln.dat[pmatch.rm_eo],
431 				    "%lc", &wend) != 1)
432 					r = REG_NOMATCH;
433 				else if (iswword(wbegin) ||
434 				    iswword(wend))
435 					r = REG_NOMATCH;
436 				/*
437 				 * If we're doing whole word matching and we
438 				 * matched once, then we should try the pattern
439 				 * again after advancing just past the start of
440 				 * the earliest match. This allows the pattern
441 				 * to  match later on in the line and possibly
442 				 * still match a whole word.
443 				 */
444 				if (r == REG_NOMATCH &&
445 				    (retry == pc->lnstart ||
446 				    pmatch.rm_so + 1 < retry))
447 					retry = pmatch.rm_so + 1;
448 				if (r == REG_NOMATCH)
449 					continue;
450 			}
451 			lastmatches++;
452 			lastmatch = pmatch;
453 
454 			if (matchidx == 0)
455 				c++;
456 
457 			/*
458 			 * Replace previous match if the new one is earlier
459 			 * and/or longer. This will lead to some amount of
460 			 * extra work if -o/--color are specified, but it's
461 			 * worth it from a correctness point of view.
462 			 */
463 			if (matchidx > startm) {
464 				chkmatch = pc->matches[matchidx - 1];
465 				if (pmatch.rm_so < chkmatch.rm_so ||
466 				    (pmatch.rm_so == chkmatch.rm_so &&
467 				    (pmatch.rm_eo - pmatch.rm_so) >
468 				    (chkmatch.rm_eo - chkmatch.rm_so))) {
469 					pc->matches[matchidx - 1] = pmatch;
470 					nst = pmatch.rm_eo;
471 				}
472 			} else {
473 				/* Advance as normal if not */
474 				pc->matches[matchidx++] = pmatch;
475 				nst = pmatch.rm_eo;
476 			}
477 			/* avoid excessive matching - skip further patterns */
478 			if ((color == NULL && !oflag) || qflag || lflag ||
479 			    matchidx >= MAX_MATCHES) {
480 				pc->lnstart = nst;
481 				lastmatches = 0;
482 				break;
483 			}
484 		}
485 
486 		/*
487 		 * Advance to just past the start of the earliest match, try
488 		 * again just in case we still have a chance to match later in
489 		 * the string.
490 		 */
491 		if (lastmatches == 0 && retry > pc->lnstart) {
492 			st = retry;
493 			continue;
494 		}
495 
496 		/* One pass if we are not recording matches */
497 		if (!wflag && ((color == NULL && !oflag) || qflag || lflag || Lflag))
498 			break;
499 
500 		/* If we didn't have any matches or REG_NOSUB set */
501 		if (lastmatches == 0 || (cflags & REG_NOSUB))
502 			nst = pc->ln.len;
503 
504 		if (lastmatches == 0)
505 			/* No matches */
506 			break;
507 		else if (st == nst && lastmatch.rm_so == lastmatch.rm_eo)
508 			/* Zero-length match -- advance one more so we don't get stuck */
509 			nst++;
510 
511 		/* Advance st based on previous matches */
512 		st = nst;
513 		pc->lnstart = st;
514 	}
515 
516 	/* Reflect the new matchidx in the context */
517 	pc->matchidx = matchidx;
518 	if (vflag)
519 		c = !c;
520 	return (c ? 0 : 1);
521 }
522 
523 /*
524  * Safe malloc() for internal use.
525  */
526 void *
527 grep_malloc(size_t size)
528 {
529 	void *ptr;
530 
531 	if ((ptr = malloc(size)) == NULL)
532 		err(2, "malloc");
533 	return (ptr);
534 }
535 
536 /*
537  * Safe calloc() for internal use.
538  */
539 void *
540 grep_calloc(size_t nmemb, size_t size)
541 {
542 	void *ptr;
543 
544 	if ((ptr = calloc(nmemb, size)) == NULL)
545 		err(2, "calloc");
546 	return (ptr);
547 }
548 
549 /*
550  * Safe realloc() for internal use.
551  */
552 void *
553 grep_realloc(void *ptr, size_t size)
554 {
555 
556 	if ((ptr = realloc(ptr, size)) == NULL)
557 		err(2, "realloc");
558 	return (ptr);
559 }
560 
561 /*
562  * Safe strdup() for internal use.
563  */
564 char *
565 grep_strdup(const char *str)
566 {
567 	char *ret;
568 
569 	if ((ret = strdup(str)) == NULL)
570 		err(2, "strdup");
571 	return (ret);
572 }
573 
574 /*
575  * Print an entire line as-is, there are no inline matches to consider. This is
576  * used for printing context.
577  */
578 void grep_printline(struct str *line, int sep) {
579 	printline_metadata(line, sep);
580 	fwrite(line->dat, line->len, 1, stdout);
581 	putchar(fileeol);
582 }
583 
584 static void
585 printline_metadata(struct str *line, int sep)
586 {
587 	bool printsep;
588 
589 	printsep = false;
590 	if (!hflag) {
591 		if (!nullflag) {
592 			fputs(line->file, stdout);
593 			printsep = true;
594 		} else {
595 			printf("%s", line->file);
596 			putchar(0);
597 		}
598 	}
599 	if (nflag) {
600 		if (printsep)
601 			putchar(sep);
602 		printf("%d", line->line_no);
603 		printsep = true;
604 	}
605 	if (bflag) {
606 		if (printsep)
607 			putchar(sep);
608 		printf("%lld", (long long)(line->off + line->boff));
609 		printsep = true;
610 	}
611 	if (printsep)
612 		putchar(sep);
613 }
614 
615 /*
616  * Prints a matching line according to the command line options.
617  */
618 static void
619 printline(struct parsec *pc, int sep)
620 {
621 	size_t a = 0;
622 	size_t i, matchidx;
623 	regmatch_t match;
624 
625 	/* If matchall, everything matches but don't actually print for -o */
626 	if (oflag && matchall)
627 		return;
628 
629 	matchidx = pc->matchidx;
630 
631 	/* --color and -o */
632 	if ((oflag || color) && matchidx > 0) {
633 		/* Only print metadata once per line if --color */
634 		if (!oflag && pc->printed == 0)
635 			printline_metadata(&pc->ln, sep);
636 		for (i = 0; i < matchidx; i++) {
637 			match = pc->matches[i];
638 			/* Don't output zero length matches */
639 			if (match.rm_so == match.rm_eo)
640 				continue;
641 			/*
642 			 * Metadata is printed on a per-line basis, so every
643 			 * match gets file metadata with the -o flag.
644 			 */
645 			if (oflag) {
646 				pc->ln.boff = match.rm_so;
647 				printline_metadata(&pc->ln, sep);
648 			} else
649 				fwrite(pc->ln.dat + a, match.rm_so - a, 1,
650 				    stdout);
651 			if (color)
652 				fprintf(stdout, "\33[%sm\33[K", color);
653 			fwrite(pc->ln.dat + match.rm_so,
654 			    match.rm_eo - match.rm_so, 1, stdout);
655 			if (color)
656 				fprintf(stdout, "\33[m\33[K");
657 			a = match.rm_eo;
658 			if (oflag)
659 				putchar('\n');
660 		}
661 		if (!oflag) {
662 			if (pc->ln.len - a > 0)
663 				fwrite(pc->ln.dat + a, pc->ln.len - a, 1,
664 				    stdout);
665 			putchar('\n');
666 		}
667 	} else
668 		grep_printline(&pc->ln, sep);
669 	pc->printed++;
670 }
671