xref: /freebsd/usr.bin/grep/util.c (revision 0183e0151669735d62584fbba9125ed90716af5e)
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, printmatch, same_file;
205 
206 	if (strcmp(fn, "-") == 0) {
207 		fn = label != NULL ? label : getstr(1);
208 		f = grep_open(NULL);
209 	} else {
210 		if (!stat(fn, &sb)) {
211 			/* Check if we need to process the file */
212 			s = sb.st_mode & S_IFMT;
213 			if (s == S_IFDIR && dirbehave == DIR_SKIP)
214 				return (0);
215 			if ((s == S_IFIFO || s == S_IFCHR || s == S_IFBLK
216 				|| s == S_IFSOCK) && devbehave == DEV_SKIP)
217 					return (0);
218 		}
219 		f = grep_open(fn);
220 	}
221 	if (f == NULL) {
222 		file_err = true;
223 		if (!sflag)
224 			warn("%s", fn);
225 		return (0);
226 	}
227 
228 	/* Convenience */
229 	ln = &pc.ln;
230 	pc.ln.file = grep_malloc(strlen(fn) + 1);
231 	strcpy(pc.ln.file, fn);
232 	pc.ln.line_no = 0;
233 	pc.ln.len = 0;
234 	pc.ln.off = -1;
235 	pc.binary = f->binary;
236 	tail = 0;
237 	last_outed = 0;
238 	same_file = false;
239 	doctx = false;
240 	printmatch = true;
241 	if ((pc.binary && binbehave == BINFILE_BIN) || cflag || qflag ||
242 	    lflag || Lflag)
243 		printmatch = false;
244 	if (printmatch && (Aflag != 0 || Bflag != 0))
245 		doctx = true;
246 	mcount = mlimit;
247 
248 	for (c = 0;  c == 0 || !(lflag || qflag); ) {
249 		/* Reset match count for every line processed */
250 		pc.matchidx = 0;
251 		pc.ln.off += pc.ln.len + 1;
252 		if ((pc.ln.dat = grep_fgetln(f, &pc.ln.len)) == NULL ||
253 		    pc.ln.len == 0) {
254 			if (pc.ln.line_no == 0 && matchall)
255 				/*
256 				 * An empty file with an empty pattern and the
257 				 * -w flag does not match
258 				 */
259 				exit(matchall && wflag ? 1 : 0);
260 			else
261 				break;
262 		}
263 
264 		if (pc.ln.len > 0 && pc.ln.dat[pc.ln.len - 1] == fileeol)
265 			--pc.ln.len;
266 		pc.ln.line_no++;
267 
268 		/* Return if we need to skip a binary file */
269 		if (pc.binary && binbehave == BINFILE_SKIP) {
270 			grep_close(f);
271 			free(pc.ln.file);
272 			free(f);
273 			return (0);
274 		}
275 
276 		if ((t = procline(&pc)) == 0)
277 			++c;
278 
279 		/* Deal with any -B context or context separators */
280 		if (t == 0 && doctx) {
281 			if (!first_match && (!same_file || last_outed > 0))
282 				printf("--\n");
283 			if (Bflag > 0)
284 				printqueue();
285 			tail = Aflag;
286 		}
287 		/* Print the matching line, but only if not quiet/binary */
288 		if (t == 0 && printmatch) {
289 			printline(&pc, ':');
290 			first_match = false;
291 			same_file = true;
292 			last_outed = 0;
293 		}
294 		if (t != 0 && doctx) {
295 			/* Deal with any -A context */
296 			if (tail > 0) {
297 				printline(&pc, '-');
298 				tail--;
299 				if (Bflag > 0)
300 					clearqueue();
301 			} else {
302 				/*
303 				 * Enqueue non-matching lines for -B context.
304 				 * If we're not actually doing -B context or if
305 				 * the enqueue resulted in a line being rotated
306 				 * out, then go ahead and increment last_outed
307 				 * to signify a gap between context/match.
308 				 */
309 				if (Bflag == 0 || (Bflag > 0 && enqueue(ln)))
310 					++last_outed;
311 			}
312 		}
313 
314 		/* Count the matches if we have a match limit */
315 		if (t == 0 && mflag) {
316 			--mcount;
317 			if (mflag && mcount <= 0)
318 				break;
319 		}
320 
321 	}
322 	if (Bflag > 0)
323 		clearqueue();
324 	grep_close(f);
325 
326 	if (cflag) {
327 		if (!hflag)
328 			printf("%s:", pc.ln.file);
329 		printf("%u\n", c);
330 	}
331 	if (lflag && !qflag && c != 0)
332 		printf("%s%c", fn, nullflag ? 0 : '\n');
333 	if (Lflag && !qflag && c == 0)
334 		printf("%s%c", fn, nullflag ? 0 : '\n');
335 	if (c && !cflag && !lflag && !Lflag &&
336 	    binbehave == BINFILE_BIN && f->binary && !qflag)
337 		printf(getstr(8), fn);
338 
339 	free(pc.ln.file);
340 	free(f);
341 	return (c);
342 }
343 
344 #define iswword(x)	(iswalnum((x)) || (x) == L'_')
345 
346 /*
347  * Processes a line comparing it with the specified patterns.  Each pattern
348  * is looped to be compared along with the full string, saving each and every
349  * match, which is necessary to colorize the output and to count the
350  * matches.  The matching lines are passed to printline() to display the
351  * appropriate output.
352  */
353 static int
354 procline(struct parsec *pc)
355 {
356 	regmatch_t pmatch, lastmatch, chkmatch;
357 	wchar_t wbegin, wend;
358 	size_t st = 0, nst = 0;
359 	unsigned int i;
360 	int c = 0, r = 0, lastmatches = 0, leflags = eflags;
361 	size_t startm = 0, matchidx;
362 	int retry;
363 
364 	matchidx = pc->matchidx;
365 
366 	/* Special case: empty pattern with -w flag, check first character */
367 	if (matchall && wflag) {
368 		if (pc->ln.len == 0)
369 			return (0);
370 		wend = L' ';
371 		if (sscanf(&pc->ln.dat[0], "%lc", &wend) != 1 || iswword(wend))
372 			return (1);
373 		else
374 			return (0);
375 	} else if (matchall)
376 		return (0);
377 
378 	/* Initialize to avoid a false positive warning from GCC. */
379 	lastmatch.rm_so = lastmatch.rm_eo = 0;
380 
381 	/* Loop to process the whole line */
382 	while (st <= pc->ln.len) {
383 		lastmatches = 0;
384 		startm = matchidx;
385 		retry = 0;
386 		if (st > 0)
387 			leflags |= REG_NOTBOL;
388 		/* Loop to compare with all the patterns */
389 		for (i = 0; i < patterns; i++) {
390 			pmatch.rm_so = st;
391 			pmatch.rm_eo = pc->ln.len;
392 #ifndef WITHOUT_FASTMATCH
393 			if (fg_pattern[i].pattern)
394 				r = fastexec(&fg_pattern[i],
395 				    pc->ln.dat, 1, &pmatch, leflags);
396 			else
397 #endif
398 				r = regexec(&r_pattern[i], pc->ln.dat, 1,
399 				    &pmatch, leflags);
400 			if (r != 0)
401 				continue;
402 			/* Check for full match */
403 			if (xflag && (pmatch.rm_so != 0 ||
404 			    (size_t)pmatch.rm_eo != pc->ln.len))
405 				continue;
406 			/* Check for whole word match */
407 #ifndef WITHOUT_FASTMATCH
408 			if (wflag || fg_pattern[i].word) {
409 #else
410 			if (wflag) {
411 #endif
412 				wbegin = wend = L' ';
413 				if (pmatch.rm_so != 0 &&
414 				    sscanf(&pc->ln.dat[pmatch.rm_so - 1],
415 				    "%lc", &wbegin) != 1)
416 					r = REG_NOMATCH;
417 				else if ((size_t)pmatch.rm_eo !=
418 				    pc->ln.len &&
419 				    sscanf(&pc->ln.dat[pmatch.rm_eo],
420 				    "%lc", &wend) != 1)
421 					r = REG_NOMATCH;
422 				else if (iswword(wbegin) ||
423 				    iswword(wend))
424 					r = REG_NOMATCH;
425 				/*
426 				 * If we're doing whole word matching and we
427 				 * matched once, then we should try the pattern
428 				 * again after advancing just past the start of
429 				 * the earliest match. This allows the pattern
430 				 * to  match later on in the line and possibly
431 				 * still match a whole word.
432 				 */
433 				if (r == REG_NOMATCH &&
434 				    (retry == 0 || pmatch.rm_so + 1 < retry))
435 					retry = pmatch.rm_so + 1;
436 				if (r == REG_NOMATCH)
437 					continue;
438 			}
439 
440 			lastmatches++;
441 			lastmatch = pmatch;
442 
443 			if (matchidx == 0)
444 				c++;
445 
446 			/*
447 			 * Replace previous match if the new one is earlier
448 			 * and/or longer. This will lead to some amount of
449 			 * extra work if -o/--color are specified, but it's
450 			 * worth it from a correctness point of view.
451 			 */
452 			if (matchidx > startm) {
453 				chkmatch = pc->matches[matchidx - 1];
454 				if (pmatch.rm_so < chkmatch.rm_so ||
455 				    (pmatch.rm_so == chkmatch.rm_so &&
456 				    (pmatch.rm_eo - pmatch.rm_so) >
457 				    (chkmatch.rm_eo - chkmatch.rm_so))) {
458 					pc->matches[matchidx - 1] = pmatch;
459 					nst = pmatch.rm_eo;
460 				}
461 			} else {
462 				/* Advance as normal if not */
463 				pc->matches[matchidx++] = pmatch;
464 				nst = pmatch.rm_eo;
465 			}
466 			/* avoid excessive matching - skip further patterns */
467 			if ((color == NULL && !oflag) || qflag || lflag ||
468 			    matchidx >= MAX_LINE_MATCHES)
469 				break;
470 		}
471 
472 		/*
473 		 * Advance to just past the start of the earliest match, try
474 		 * again just in case we still have a chance to match later in
475 		 * the string.
476 		 */
477 		if (lastmatches == 0 && retry > 0) {
478 			st = retry;
479 			continue;
480 		}
481 
482 		/* One pass if we are not recording matches */
483 		if (!wflag && ((color == NULL && !oflag) || qflag || lflag || Lflag))
484 			break;
485 
486 		/* If we didn't have any matches or REG_NOSUB set */
487 		if (lastmatches == 0 || (cflags & REG_NOSUB))
488 			nst = pc->ln.len;
489 
490 		if (lastmatches == 0)
491 			/* No matches */
492 			break;
493 		else if (st == nst && lastmatch.rm_so == lastmatch.rm_eo)
494 			/* Zero-length match -- advance one more so we don't get stuck */
495 			nst++;
496 
497 		/* Advance st based on previous matches */
498 		st = nst;
499 	}
500 
501 	/* Reflect the new matchidx in the context */
502 	pc->matchidx = matchidx;
503 	if (vflag)
504 		c = !c;
505 	return (c ? 0 : 1);
506 }
507 
508 /*
509  * Safe malloc() for internal use.
510  */
511 void *
512 grep_malloc(size_t size)
513 {
514 	void *ptr;
515 
516 	if ((ptr = malloc(size)) == NULL)
517 		err(2, "malloc");
518 	return (ptr);
519 }
520 
521 /*
522  * Safe calloc() for internal use.
523  */
524 void *
525 grep_calloc(size_t nmemb, size_t size)
526 {
527 	void *ptr;
528 
529 	if ((ptr = calloc(nmemb, size)) == NULL)
530 		err(2, "calloc");
531 	return (ptr);
532 }
533 
534 /*
535  * Safe realloc() for internal use.
536  */
537 void *
538 grep_realloc(void *ptr, size_t size)
539 {
540 
541 	if ((ptr = realloc(ptr, size)) == NULL)
542 		err(2, "realloc");
543 	return (ptr);
544 }
545 
546 /*
547  * Safe strdup() for internal use.
548  */
549 char *
550 grep_strdup(const char *str)
551 {
552 	char *ret;
553 
554 	if ((ret = strdup(str)) == NULL)
555 		err(2, "strdup");
556 	return (ret);
557 }
558 
559 /*
560  * Print an entire line as-is, there are no inline matches to consider. This is
561  * used for printing context.
562  */
563 void grep_printline(struct str *line, int sep) {
564 	printline_metadata(line, sep);
565 	fwrite(line->dat, line->len, 1, stdout);
566 	putchar(fileeol);
567 }
568 
569 static void
570 printline_metadata(struct str *line, int sep)
571 {
572 	bool printsep;
573 
574 	printsep = false;
575 	if (!hflag) {
576 		if (!nullflag) {
577 			fputs(line->file, stdout);
578 			printsep = true;
579 		} else {
580 			printf("%s", line->file);
581 			putchar(0);
582 		}
583 	}
584 	if (nflag) {
585 		if (printsep)
586 			putchar(sep);
587 		printf("%d", line->line_no);
588 		printsep = true;
589 	}
590 	if (bflag) {
591 		if (printsep)
592 			putchar(sep);
593 		printf("%lld", (long long)line->off);
594 		printsep = true;
595 	}
596 	if (printsep)
597 		putchar(sep);
598 }
599 
600 /*
601  * Prints a matching line according to the command line options.
602  */
603 static void
604 printline(struct parsec *pc, int sep)
605 {
606 	size_t a = 0;
607 	size_t i, matchidx;
608 	regmatch_t match;
609 
610 	/* If matchall, everything matches but don't actually print for -o */
611 	if (oflag && matchall)
612 		return;
613 
614 	matchidx = pc->matchidx;
615 
616 	/* --color and -o */
617 	if ((oflag || color) && matchidx > 0) {
618 		printline_metadata(&pc->ln, sep);
619 		for (i = 0; i < matchidx; i++) {
620 			match = pc->matches[i];
621 			/* Don't output zero length matches */
622 			if (match.rm_so == match.rm_eo)
623 				continue;
624 			if (!oflag)
625 				fwrite(pc->ln.dat + a, match.rm_so - a, 1,
626 				    stdout);
627 			if (color)
628 				fprintf(stdout, "\33[%sm\33[K", color);
629 			fwrite(pc->ln.dat + match.rm_so,
630 			    match.rm_eo - match.rm_so, 1, stdout);
631 			if (color)
632 				fprintf(stdout, "\33[m\33[K");
633 			a = match.rm_eo;
634 			if (oflag)
635 				putchar('\n');
636 		}
637 		if (!oflag) {
638 			if (pc->ln.len - a > 0)
639 				fwrite(pc->ln.dat + a, pc->ln.len - a, 1,
640 				    stdout);
641 			putchar('\n');
642 		}
643 	} else
644 		grep_printline(&pc->ln, sep);
645 }
646