xref: /freebsd/usr.bin/grep/util.c (revision e3514747256465c52c3b2aedc9795f52c0d3efe9)
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  * All rights reserved.
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  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/stat.h>
36 #include <sys/types.h>
37 
38 #include <ctype.h>
39 #include <err.h>
40 #include <errno.h>
41 #include <fnmatch.h>
42 #include <fts.h>
43 #include <libgen.h>
44 #include <stdbool.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 #include <wchar.h>
50 #include <wctype.h>
51 
52 #ifndef WITHOUT_FASTMATCH
53 #include "fastmatch.h"
54 #endif
55 #include "grep.h"
56 
57 static bool	 first_match = true;
58 
59 /*
60  * Parsing context; used to hold things like matches made and
61  * other useful bits
62  */
63 struct parsec {
64 	regmatch_t matches[MAX_LINE_MATCHES];	/* Matches made */
65 	struct str ln;				/* Current line */
66 	size_t matchidx;			/* Latest used match index */
67 	bool binary;				/* Binary file? */
68 };
69 
70 
71 static int procline(struct parsec *pc);
72 static void printline(struct parsec *pc, int sep);
73 static void printline_metadata(struct str *line, int sep);
74 
75 bool
76 file_matching(const char *fname)
77 {
78 	char *fname_base, *fname_buf;
79 	bool ret;
80 
81 	ret = finclude ? false : true;
82 	fname_buf = strdup(fname);
83 	if (fname_buf == NULL)
84 		err(2, "strdup");
85 	fname_base = basename(fname_buf);
86 
87 	for (unsigned int i = 0; i < fpatterns; ++i) {
88 		if (fnmatch(fpattern[i].pat, fname, 0) == 0 ||
89 		    fnmatch(fpattern[i].pat, fname_base, 0) == 0) {
90 			if (fpattern[i].mode == EXCL_PAT) {
91 				ret = false;
92 				break;
93 			} else
94 				ret = true;
95 		}
96 	}
97 	free(fname_buf);
98 	return (ret);
99 }
100 
101 static inline bool
102 dir_matching(const char *dname)
103 {
104 	bool ret;
105 
106 	ret = dinclude ? false : true;
107 
108 	for (unsigned int i = 0; i < dpatterns; ++i) {
109 		if (dname != NULL &&
110 		    fnmatch(dpattern[i].pat, dname, 0) == 0) {
111 			if (dpattern[i].mode == EXCL_PAT)
112 				return (false);
113 			else
114 				ret = true;
115 		}
116 	}
117 	return (ret);
118 }
119 
120 /*
121  * Processes a directory when a recursive search is performed with
122  * the -R option.  Each appropriate file is passed to procfile().
123  */
124 int
125 grep_tree(char **argv)
126 {
127 	FTS *fts;
128 	FTSENT *p;
129 	int c, fts_flags;
130 	bool ok;
131 	const char *wd[] = { ".", NULL };
132 
133 	c = fts_flags = 0;
134 
135 	switch(linkbehave) {
136 	case LINK_EXPLICIT:
137 		fts_flags = FTS_COMFOLLOW;
138 		break;
139 	case LINK_SKIP:
140 		fts_flags = FTS_PHYSICAL;
141 		break;
142 	default:
143 		fts_flags = FTS_LOGICAL;
144 
145 	}
146 
147 	fts_flags |= FTS_NOSTAT | FTS_NOCHDIR;
148 
149 	fts = fts_open((argv[0] == NULL) ?
150 	    __DECONST(char * const *, wd) : argv, fts_flags, NULL);
151 	if (fts == NULL)
152 		err(2, "fts_open");
153 	while ((p = fts_read(fts)) != NULL) {
154 		switch (p->fts_info) {
155 		case FTS_DNR:
156 			/* FALLTHROUGH */
157 		case FTS_ERR:
158 			file_err = true;
159 			if(!sflag)
160 				warnx("%s: %s", p->fts_path, strerror(p->fts_errno));
161 			break;
162 		case FTS_D:
163 			/* FALLTHROUGH */
164 		case FTS_DP:
165 			if (dexclude || dinclude)
166 				if (!dir_matching(p->fts_name) ||
167 				    !dir_matching(p->fts_path))
168 					fts_set(fts, p, FTS_SKIP);
169 			break;
170 		case FTS_DC:
171 			/* Print a warning for recursive directory loop */
172 			warnx("warning: %s: recursive directory loop",
173 				p->fts_path);
174 			break;
175 		default:
176 			/* Check for file exclusion/inclusion */
177 			ok = true;
178 			if (fexclude || finclude)
179 				ok &= file_matching(p->fts_path);
180 
181 			if (ok)
182 				c += procfile(p->fts_path);
183 			break;
184 		}
185 	}
186 
187 	fts_close(fts);
188 	return (c);
189 }
190 
191 /*
192  * Opens a file and processes it.  Each file is processed line-by-line
193  * passing the lines to procline().
194  */
195 int
196 procfile(const char *fn)
197 {
198 	struct parsec pc;
199 	struct file *f;
200 	struct stat sb;
201 	struct str *ln;
202 	mode_t s;
203 	int c, last_outed, t, tail;
204 	bool doctx, same_file;
205 
206 	doctx = false;
207 	if ((!pc.binary || binbehave != BINFILE_BIN) && !cflag && !qflag &&
208 	    !lflag && !Lflag && (Aflag != 0 || Bflag != 0))
209 		doctx = true;
210 	mcount = mlimit;
211 
212 	if (strcmp(fn, "-") == 0) {
213 		fn = label != NULL ? label : getstr(1);
214 		f = grep_open(NULL);
215 	} else {
216 		if (!stat(fn, &sb)) {
217 			/* Check if we need to process the file */
218 			s = sb.st_mode & S_IFMT;
219 			if (s == S_IFDIR && dirbehave == DIR_SKIP)
220 				return (0);
221 			if ((s == S_IFIFO || s == S_IFCHR || s == S_IFBLK
222 				|| s == S_IFSOCK) && devbehave == DEV_SKIP)
223 					return (0);
224 		}
225 		f = grep_open(fn);
226 	}
227 	if (f == NULL) {
228 		file_err = true;
229 		if (!sflag)
230 			warn("%s", fn);
231 		return (0);
232 	}
233 
234 	/* Convenience */
235 	ln = &pc.ln;
236 	pc.ln.file = grep_malloc(strlen(fn) + 1);
237 	strcpy(pc.ln.file, fn);
238 	pc.ln.line_no = 0;
239 	pc.ln.len = 0;
240 	pc.ln.off = -1;
241 	pc.binary = f->binary;
242 	tail = 0;
243 	last_outed = 0;
244 	same_file = false;
245 
246 	for (c = 0;  c == 0 || !(lflag || qflag); ) {
247 		/* Reset match count for every line processed */
248 		pc.matchidx = 0;
249 		pc.ln.off += pc.ln.len + 1;
250 		if ((pc.ln.dat = grep_fgetln(f, &pc.ln.len)) == NULL ||
251 		    pc.ln.len == 0) {
252 			if (pc.ln.line_no == 0 && matchall)
253 				/*
254 				 * An empty file with an empty pattern and the
255 				 * -w flag does not match
256 				 */
257 				exit(matchall && wflag ? 1 : 0);
258 			else
259 				break;
260 		}
261 
262 		if (pc.ln.len > 0 && pc.ln.dat[pc.ln.len - 1] == fileeol)
263 			--pc.ln.len;
264 		pc.ln.line_no++;
265 
266 		/* Return if we need to skip a binary file */
267 		if (pc.binary && binbehave == BINFILE_SKIP) {
268 			grep_close(f);
269 			free(pc.ln.file);
270 			free(f);
271 			return (0);
272 		}
273 
274 		if ((t = procline(&pc)) == 0)
275 			++c;
276 
277 		/* Deal with any -B context or context separators */
278 		if (t == 0 && doctx) {
279 			if (!first_match && (!same_file || last_outed > 0))
280 				printf("--\n");
281 			if (Bflag > 0)
282 				printqueue();
283 			tail = Aflag;
284 		}
285 		/* Print the matching line, but only if not quiet/binary */
286 		if (t == 0 && !qflag && !pc.binary) {
287 			printline(&pc, ':');
288 			first_match = false;
289 			same_file = true;
290 			last_outed = 0;
291 		}
292 		if (t != 0 && doctx) {
293 			/* Deal with any -A context */
294 			if (tail > 0) {
295 				printline(&pc, '-');
296 				tail--;
297 				if (Bflag > 0)
298 					clearqueue();
299 			} else {
300 				/*
301 				 * Enqueue non-matching lines for -B context.
302 				 * If we're not actually doing -B context or if
303 				 * the enqueue resulted in a line being rotated
304 				 * out, then go ahead and increment last_outed
305 				 * to signify a gap between context/match.
306 				 */
307 				if (Bflag == 0 || (Bflag > 0 && enqueue(ln)))
308 					++last_outed;
309 			}
310 		}
311 
312 		/* Count the matches if we have a match limit */
313 		if (t == 0 && mflag) {
314 			--mcount;
315 			if (mflag && mcount <= 0)
316 				break;
317 		}
318 
319 	}
320 	if (Bflag > 0)
321 		clearqueue();
322 	grep_close(f);
323 
324 	if (cflag) {
325 		if (!hflag)
326 			printf("%s:", pc.ln.file);
327 		printf("%u\n", c);
328 	}
329 	if (lflag && !qflag && c != 0)
330 		printf("%s%c", fn, nullflag ? 0 : '\n');
331 	if (Lflag && !qflag && c == 0)
332 		printf("%s%c", fn, nullflag ? 0 : '\n');
333 	if (c && !cflag && !lflag && !Lflag &&
334 	    binbehave == BINFILE_BIN && f->binary && !qflag)
335 		printf(getstr(8), fn);
336 
337 	free(pc.ln.file);
338 	free(f);
339 	return (c);
340 }
341 
342 #define iswword(x)	(iswalnum((x)) || (x) == L'_')
343 
344 /*
345  * Processes a line comparing it with the specified patterns.  Each pattern
346  * is looped to be compared along with the full string, saving each and every
347  * match, which is necessary to colorize the output and to count the
348  * matches.  The matching lines are passed to printline() to display the
349  * appropriate output.
350  */
351 static int
352 procline(struct parsec *pc)
353 {
354 	regmatch_t pmatch, lastmatch, chkmatch;
355 	wchar_t wbegin, wend;
356 	size_t st = 0, nst = 0;
357 	unsigned int i;
358 	int c = 0, r = 0, lastmatches = 0, leflags = eflags;
359 	size_t startm = 0, matchidx;
360 	int retry;
361 
362 	matchidx = pc->matchidx;
363 
364 	/* Special case: empty pattern with -w flag, check first character */
365 	if (matchall && wflag) {
366 		if (pc->ln.len == 0)
367 			return (0);
368 		wend = L' ';
369 		if (sscanf(&pc->ln.dat[0], "%lc", &wend) != 1 || iswword(wend))
370 			return (1);
371 		else
372 			return (0);
373 	} else if (matchall)
374 		return (0);
375 
376 	/* Initialize to avoid a false positive warning from GCC. */
377 	lastmatch.rm_so = lastmatch.rm_eo = 0;
378 
379 	/* Loop to process the whole line */
380 	while (st <= pc->ln.len) {
381 		lastmatches = 0;
382 		startm = matchidx;
383 		retry = 0;
384 		if (st > 0)
385 			leflags |= REG_NOTBOL;
386 		/* Loop to compare with all the patterns */
387 		for (i = 0; i < patterns; i++) {
388 			pmatch.rm_so = st;
389 			pmatch.rm_eo = pc->ln.len;
390 #ifndef WITHOUT_FASTMATCH
391 			if (fg_pattern[i].pattern)
392 				r = fastexec(&fg_pattern[i],
393 				    pc->ln.dat, 1, &pmatch, leflags);
394 			else
395 #endif
396 				r = regexec(&r_pattern[i], pc->ln.dat, 1,
397 				    &pmatch, leflags);
398 			if (r != 0)
399 				continue;
400 			/* Check for full match */
401 			if (xflag && (pmatch.rm_so != 0 ||
402 			    (size_t)pmatch.rm_eo != pc->ln.len))
403 				continue;
404 			/* Check for whole word match */
405 #ifndef WITHOUT_FASTMATCH
406 			if (wflag || fg_pattern[i].word) {
407 #else
408 			if (wflag) {
409 #endif
410 				wbegin = wend = L' ';
411 				if (pmatch.rm_so != 0 &&
412 				    sscanf(&pc->ln.dat[pmatch.rm_so - 1],
413 				    "%lc", &wbegin) != 1)
414 					r = REG_NOMATCH;
415 				else if ((size_t)pmatch.rm_eo !=
416 				    pc->ln.len &&
417 				    sscanf(&pc->ln.dat[pmatch.rm_eo],
418 				    "%lc", &wend) != 1)
419 					r = REG_NOMATCH;
420 				else if (iswword(wbegin) ||
421 				    iswword(wend))
422 					r = REG_NOMATCH;
423 				/*
424 				 * If we're doing whole word matching and we
425 				 * matched once, then we should try the pattern
426 				 * again after advancing just past the start of
427 				 * the earliest match. This allows the pattern
428 				 * to  match later on in the line and possibly
429 				 * still match a whole word.
430 				 */
431 				if (r == REG_NOMATCH &&
432 				    (retry == 0 || pmatch.rm_so + 1 < retry))
433 					retry = pmatch.rm_so + 1;
434 				if (r == REG_NOMATCH)
435 					continue;
436 			}
437 
438 			lastmatches++;
439 			lastmatch = pmatch;
440 
441 			if (matchidx == 0)
442 				c++;
443 
444 			/*
445 			 * Replace previous match if the new one is earlier
446 			 * and/or longer. This will lead to some amount of
447 			 * extra work if -o/--color are specified, but it's
448 			 * worth it from a correctness point of view.
449 			 */
450 			if (matchidx > startm) {
451 				chkmatch = pc->matches[matchidx - 1];
452 				if (pmatch.rm_so < chkmatch.rm_so ||
453 				    (pmatch.rm_so == chkmatch.rm_so &&
454 				    (pmatch.rm_eo - pmatch.rm_so) >
455 				    (chkmatch.rm_eo - chkmatch.rm_so))) {
456 					pc->matches[matchidx - 1] = pmatch;
457 					nst = pmatch.rm_eo;
458 				}
459 			} else {
460 				/* Advance as normal if not */
461 				pc->matches[matchidx++] = pmatch;
462 				nst = pmatch.rm_eo;
463 			}
464 			/* avoid excessive matching - skip further patterns */
465 			if ((color == NULL && !oflag) || qflag || lflag ||
466 			    matchidx >= MAX_LINE_MATCHES)
467 				break;
468 		}
469 
470 		/*
471 		 * Advance to just past the start of the earliest match, try
472 		 * again just in case we still have a chance to match later in
473 		 * the string.
474 		 */
475 		if (lastmatches == 0 && retry > 0) {
476 			st = retry;
477 			continue;
478 		}
479 
480 		/* One pass if we are not recording matches */
481 		if (!wflag && ((color == NULL && !oflag) || qflag || lflag || Lflag))
482 			break;
483 
484 		/* If we didn't have any matches or REG_NOSUB set */
485 		if (lastmatches == 0 || (cflags & REG_NOSUB))
486 			nst = pc->ln.len;
487 
488 		if (lastmatches == 0)
489 			/* No matches */
490 			break;
491 		else if (st == nst && lastmatch.rm_so == lastmatch.rm_eo)
492 			/* Zero-length match -- advance one more so we don't get stuck */
493 			nst++;
494 
495 		/* Advance st based on previous matches */
496 		st = nst;
497 	}
498 
499 	/* Reflect the new matchidx in the context */
500 	pc->matchidx = matchidx;
501 	if (vflag)
502 		c = !c;
503 	return (c ? 0 : 1);
504 }
505 
506 /*
507  * Safe malloc() for internal use.
508  */
509 void *
510 grep_malloc(size_t size)
511 {
512 	void *ptr;
513 
514 	if ((ptr = malloc(size)) == NULL)
515 		err(2, "malloc");
516 	return (ptr);
517 }
518 
519 /*
520  * Safe calloc() for internal use.
521  */
522 void *
523 grep_calloc(size_t nmemb, size_t size)
524 {
525 	void *ptr;
526 
527 	if ((ptr = calloc(nmemb, size)) == NULL)
528 		err(2, "calloc");
529 	return (ptr);
530 }
531 
532 /*
533  * Safe realloc() for internal use.
534  */
535 void *
536 grep_realloc(void *ptr, size_t size)
537 {
538 
539 	if ((ptr = realloc(ptr, size)) == NULL)
540 		err(2, "realloc");
541 	return (ptr);
542 }
543 
544 /*
545  * Safe strdup() for internal use.
546  */
547 char *
548 grep_strdup(const char *str)
549 {
550 	char *ret;
551 
552 	if ((ret = strdup(str)) == NULL)
553 		err(2, "strdup");
554 	return (ret);
555 }
556 
557 /*
558  * Print an entire line as-is, there are no inline matches to consider. This is
559  * used for printing context.
560  */
561 void grep_printline(struct str *line, int sep) {
562 	printline_metadata(line, sep);
563 	fwrite(line->dat, line->len, 1, stdout);
564 	putchar(fileeol);
565 }
566 
567 static void
568 printline_metadata(struct str *line, int sep)
569 {
570 	bool printsep;
571 
572 	printsep = false;
573 	if (!hflag) {
574 		if (!nullflag) {
575 			fputs(line->file, stdout);
576 			printsep = true;
577 		} else {
578 			printf("%s", line->file);
579 			putchar(0);
580 		}
581 	}
582 	if (nflag) {
583 		if (printsep)
584 			putchar(sep);
585 		printf("%d", line->line_no);
586 		printsep = true;
587 	}
588 	if (bflag) {
589 		if (printsep)
590 			putchar(sep);
591 		printf("%lld", (long long)line->off);
592 		printsep = true;
593 	}
594 	if (printsep)
595 		putchar(sep);
596 }
597 
598 /*
599  * Prints a matching line according to the command line options.
600  */
601 static void
602 printline(struct parsec *pc, int sep)
603 {
604 	size_t a = 0;
605 	size_t i, matchidx;
606 	regmatch_t match;
607 
608 	/* If matchall, everything matches but don't actually print for -o */
609 	if (oflag && matchall)
610 		return;
611 
612 	matchidx = pc->matchidx;
613 
614 	/* --color and -o */
615 	if ((oflag || color) && matchidx > 0) {
616 		printline_metadata(&pc->ln, sep);
617 		for (i = 0; i < matchidx; i++) {
618 			match = pc->matches[i];
619 			/* Don't output zero length matches */
620 			if (match.rm_so == match.rm_eo)
621 				continue;
622 			if (!oflag)
623 				fwrite(pc->ln.dat + a, match.rm_so - a, 1,
624 				    stdout);
625 			if (color)
626 				fprintf(stdout, "\33[%sm\33[K", color);
627 			fwrite(pc->ln.dat + match.rm_so,
628 			    match.rm_eo - match.rm_so, 1, stdout);
629 			if (color)
630 				fprintf(stdout, "\33[m\33[K");
631 			a = match.rm_eo;
632 			if (oflag)
633 				putchar('\n');
634 		}
635 		if (!oflag) {
636 			if (pc->ln.len - a > 0)
637 				fwrite(pc->ln.dat + a, pc->ln.len - a, 1,
638 				    stdout);
639 			putchar('\n');
640 		}
641 	} else
642 		grep_printline(&pc->ln, sep);
643 }
644