xref: /freebsd/usr.bin/diff/diff.c (revision 2d5d2a986ce1a93b8567dbdf3f80bc2b545d6998)
1 /*	$OpenBSD: diff.c,v 1.67 2019/06/28 13:35:00 deraadt Exp $	*/
2 
3 /*
4  * Copyright (c) 2003 Todd C. Miller <Todd.Miller@courtesan.com>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  *
18  * Sponsored in part by the Defense Advanced Research Projects
19  * Agency (DARPA) and Air Force Research Laboratory, Air Force
20  * Materiel Command, USAF, under agreement number F39502-99-1-0512.
21  */
22 
23 #include <sys/cdefs.h>
24 __FBSDID("$FreeBSD$");
25 
26 #include <sys/stat.h>
27 
28 #include <ctype.h>
29 #include <err.h>
30 #include <errno.h>
31 #include <getopt.h>
32 #include <stdlib.h>
33 #include <stdio.h>
34 #include <string.h>
35 #include <unistd.h>
36 #include <limits.h>
37 
38 #include "diff.h"
39 #include "xmalloc.h"
40 
41 bool	 lflag, Nflag, Pflag, rflag, sflag, Tflag, cflag;
42 bool	 ignore_file_case, suppress_common, color, noderef;
43 int	 diff_format, diff_context, status;
44 int	 tabsize = 8, width = 130;
45 static int	colorflag = COLORFLAG_NEVER;
46 char	*start, *ifdefname, *diffargs, *label[2];
47 char	*ignore_pats, *most_recent_pat;
48 char	*group_format = NULL;
49 const char	*add_code, *del_code;
50 struct stat stb1, stb2;
51 struct excludes *excludes_list;
52 regex_t	 ignore_re, most_recent_re;
53 
54 #define	OPTIONS	"0123456789aBbC:cdD:efF:HhI:iL:lnNPpqrS:sTtU:uwW:X:x:y"
55 enum {
56 	OPT_TSIZE = CHAR_MAX + 1,
57 	OPT_STRIPCR,
58 	OPT_IGN_FN_CASE,
59 	OPT_NO_IGN_FN_CASE,
60 	OPT_NORMAL,
61 	OPT_HORIZON_LINES,
62 	OPT_CHANGED_GROUP_FORMAT,
63 	OPT_SUPPRESS_COMMON,
64 	OPT_COLOR,
65 	OPT_NO_DEREFERENCE,
66 };
67 
68 static struct option longopts[] = {
69 	{ "text",			no_argument,		0,	'a' },
70 	{ "ignore-space-change",	no_argument,		0,	'b' },
71 	{ "context",			optional_argument,	0,	'C' },
72 	{ "ifdef",			required_argument,	0,	'D' },
73 	{ "minimal",			no_argument,		0,	'd' },
74 	{ "ed",				no_argument,		0,	'e' },
75 	{ "forward-ed",			no_argument,		0,	'f' },
76 	{ "show-function-line",		required_argument,	0,	'F' },
77 	{ "speed-large-files",		no_argument,		NULL,	'H' },
78 	{ "ignore-blank-lines",		no_argument,		0,	'B' },
79 	{ "ignore-matching-lines",	required_argument,	0,	'I' },
80 	{ "ignore-case",		no_argument,		0,	'i' },
81 	{ "paginate",			no_argument,		NULL,	'l' },
82 	{ "label",			required_argument,	0,	'L' },
83 	{ "new-file",			no_argument,		0,	'N' },
84 	{ "rcs",			no_argument,		0,	'n' },
85 	{ "unidirectional-new-file",	no_argument,		0,	'P' },
86 	{ "show-c-function",		no_argument,		0,	'p' },
87 	{ "brief",			no_argument,		0,	'q' },
88 	{ "recursive",			no_argument,		0,	'r' },
89 	{ "report-identical-files",	no_argument,		0,	's' },
90 	{ "starting-file",		required_argument,	0,	'S' },
91 	{ "expand-tabs",		no_argument,		0,	't' },
92 	{ "initial-tab",		no_argument,		0,	'T' },
93 	{ "unified",			optional_argument,	0,	'U' },
94 	{ "ignore-all-space",		no_argument,		0,	'w' },
95 	{ "width",			required_argument,	0,	'W' },
96 	{ "exclude",			required_argument,	0,	'x' },
97 	{ "exclude-from",		required_argument,	0,	'X' },
98 	{ "side-by-side",		no_argument,		NULL,	'y' },
99 	{ "ignore-file-name-case",	no_argument,		NULL,	OPT_IGN_FN_CASE },
100 	{ "horizon-lines",		required_argument,	NULL,	OPT_HORIZON_LINES },
101 	{ "no-dereference",		no_argument,		NULL,	OPT_NO_DEREFERENCE},
102 	{ "no-ignore-file-name-case",	no_argument,		NULL,	OPT_NO_IGN_FN_CASE },
103 	{ "normal",			no_argument,		NULL,	OPT_NORMAL },
104 	{ "strip-trailing-cr",		no_argument,		NULL,	OPT_STRIPCR },
105 	{ "tabsize",			required_argument,	NULL,	OPT_TSIZE },
106 	{ "changed-group-format",	required_argument,	NULL,	OPT_CHANGED_GROUP_FORMAT},
107 	{ "suppress-common-lines",	no_argument,		NULL,	OPT_SUPPRESS_COMMON },
108 	{ "color",			optional_argument,	NULL,	OPT_COLOR },
109 	{ NULL,				0,			0,	'\0'}
110 };
111 
112 static void checked_regcomp(char const *, regex_t *);
113 static void usage(void) __dead2;
114 static void conflicting_format(void) __dead2;
115 static void push_excludes(char *);
116 static void push_ignore_pats(char *);
117 static void read_excludes_file(char *file);
118 static void set_argstr(char **, char **);
119 static char *splice(char *, char *);
120 static bool do_color(void);
121 
122 int
123 main(int argc, char **argv)
124 {
125 	const char *errstr = NULL;
126 	char *ep, **oargv;
127 	long  l;
128 	int   ch, dflags, lastch, gotstdin, prevoptind, newarg;
129 
130 	oargv = argv;
131 	gotstdin = 0;
132 	dflags = 0;
133 	lastch = '\0';
134 	prevoptind = 1;
135 	newarg = 1;
136 	diff_context = 3;
137 	diff_format = D_UNSET;
138 #define	FORMAT_MISMATCHED(type)	\
139 	(diff_format != D_UNSET && diff_format != (type))
140 	while ((ch = getopt_long(argc, argv, OPTIONS, longopts, NULL)) != -1) {
141 		switch (ch) {
142 		case '0': case '1': case '2': case '3': case '4':
143 		case '5': case '6': case '7': case '8': case '9':
144 			if (newarg)
145 				usage();	/* disallow -[0-9]+ */
146 			else if (lastch == 'c' || lastch == 'u')
147 				diff_context = 0;
148 			else if (!isdigit(lastch) || diff_context > INT_MAX / 10)
149 				usage();
150 			diff_context = (diff_context * 10) + (ch - '0');
151 			break;
152 		case 'a':
153 			dflags |= D_FORCEASCII;
154 			break;
155 		case 'b':
156 			dflags |= D_FOLDBLANKS;
157 			break;
158 		case 'C':
159 		case 'c':
160 			if (FORMAT_MISMATCHED(D_CONTEXT))
161 				conflicting_format();
162 			diff_format = D_CONTEXT;
163 			if (optarg != NULL) {
164 				l = strtol(optarg, &ep, 10);
165 				if (*ep != '\0' || l < 0 || l >= INT_MAX)
166 					usage();
167 				diff_context = (int)l;
168 			}
169 			break;
170 		case 'd':
171 			dflags |= D_MINIMAL;
172 			break;
173 		case 'D':
174 			if (FORMAT_MISMATCHED(D_IFDEF))
175 				conflicting_format();
176 			diff_format = D_IFDEF;
177 			ifdefname = optarg;
178 			break;
179 		case 'e':
180 			if (FORMAT_MISMATCHED(D_EDIT))
181 				conflicting_format();
182 			diff_format = D_EDIT;
183 			break;
184 		case 'f':
185 			if (FORMAT_MISMATCHED(D_REVERSE))
186 				conflicting_format();
187 			diff_format = D_REVERSE;
188 			break;
189 		case 'H':
190 			/* ignore but needed for compatibility with GNU diff */
191 			break;
192 		case 'h':
193 			/* silently ignore for backwards compatibility */
194 			break;
195 		case 'B':
196 			dflags |= D_SKIPBLANKLINES;
197 			break;
198 		case 'F':
199 			if (dflags & D_PROTOTYPE)
200 				conflicting_format();
201 			dflags |= D_MATCHLAST;
202 			most_recent_pat = xstrdup(optarg);
203 			break;
204 		case 'I':
205 			push_ignore_pats(optarg);
206 			break;
207 		case 'i':
208 			dflags |= D_IGNORECASE;
209 			break;
210 		case 'L':
211 			if (label[0] == NULL)
212 				label[0] = optarg;
213 			else if (label[1] == NULL)
214 				label[1] = optarg;
215 			else
216 				usage();
217 			break;
218 		case 'l':
219 			lflag = true;
220 			break;
221 		case 'N':
222 			Nflag = true;
223 			break;
224 		case 'n':
225 			if (FORMAT_MISMATCHED(D_NREVERSE))
226 				conflicting_format();
227 			diff_format = D_NREVERSE;
228 			break;
229 		case 'p':
230 			if (dflags & D_MATCHLAST)
231 				conflicting_format();
232 			dflags |= D_PROTOTYPE;
233 			break;
234 		case 'P':
235 			Pflag = true;
236 			break;
237 		case 'r':
238 			rflag = true;
239 			break;
240 		case 'q':
241 			if (FORMAT_MISMATCHED(D_BRIEF))
242 				conflicting_format();
243 			diff_format = D_BRIEF;
244 			break;
245 		case 'S':
246 			start = optarg;
247 			break;
248 		case 's':
249 			sflag = true;
250 			break;
251 		case 'T':
252 			Tflag = true;
253 			break;
254 		case 't':
255 			dflags |= D_EXPANDTABS;
256 			break;
257 		case 'U':
258 		case 'u':
259 			if (FORMAT_MISMATCHED(D_UNIFIED))
260 				conflicting_format();
261 			diff_format = D_UNIFIED;
262 			if (optarg != NULL) {
263 				l = strtol(optarg, &ep, 10);
264 				if (*ep != '\0' || l < 0 || l >= INT_MAX)
265 					usage();
266 				diff_context = (int)l;
267 			}
268 			break;
269 		case 'w':
270 			dflags |= D_IGNOREBLANKS;
271 			break;
272 		case 'W':
273 			width = (int) strtonum(optarg, 1, INT_MAX, &errstr);
274 			if (errstr) {
275 				warnx("Invalid argument for width");
276 				usage();
277 			}
278 			break;
279 		case 'X':
280 			read_excludes_file(optarg);
281 			break;
282 		case 'x':
283 			push_excludes(optarg);
284 			break;
285 		case 'y':
286 			if (FORMAT_MISMATCHED(D_SIDEBYSIDE))
287 				conflicting_format();
288 			diff_format = D_SIDEBYSIDE;
289 			break;
290 		case OPT_CHANGED_GROUP_FORMAT:
291 			if (FORMAT_MISMATCHED(D_GFORMAT))
292 				conflicting_format();
293 			diff_format = D_GFORMAT;
294 			group_format = optarg;
295 			break;
296 		case OPT_HORIZON_LINES:
297 			break; /* XXX TODO for compatibility with GNU diff3 */
298 		case OPT_IGN_FN_CASE:
299 			ignore_file_case = true;
300 			break;
301 		case OPT_NO_IGN_FN_CASE:
302 			ignore_file_case = false;
303 			break;
304 		case OPT_NORMAL:
305 			if (FORMAT_MISMATCHED(D_NORMAL))
306 				conflicting_format();
307 			diff_format = D_NORMAL;
308 			break;
309 		case OPT_TSIZE:
310 			tabsize = (int) strtonum(optarg, 1, INT_MAX, &errstr);
311 			if (errstr) {
312 				warnx("Invalid argument for tabsize");
313 				usage();
314 			}
315 			break;
316 		case OPT_STRIPCR:
317 			dflags |= D_STRIPCR;
318 			break;
319 		case OPT_SUPPRESS_COMMON:
320 			suppress_common = 1;
321 			break;
322 		case OPT_COLOR:
323 			if (optarg == NULL || strncmp(optarg, "auto", 4) == 0)
324 				colorflag = COLORFLAG_AUTO;
325 			else if (strncmp(optarg, "always", 6) == 0)
326 				colorflag = COLORFLAG_ALWAYS;
327 			else if (strncmp(optarg, "never", 5) == 0)
328 				colorflag = COLORFLAG_NEVER;
329 			else
330 				errx(2, "unsupported --color value '%s' (must be always, auto, or never)",
331 					optarg);
332 			break;
333 		case OPT_NO_DEREFERENCE:
334 			rflag = true;
335 			noderef = true;
336 			break;
337 		default:
338 			usage();
339 			break;
340 		}
341 		lastch = ch;
342 		newarg = optind != prevoptind;
343 		prevoptind = optind;
344 	}
345 	if (diff_format == D_UNSET && (dflags & D_PROTOTYPE) != 0)
346 		diff_format = D_CONTEXT;
347 	if (diff_format == D_UNSET)
348 		diff_format = D_NORMAL;
349 	argc -= optind;
350 	argv += optind;
351 
352 	if (do_color()) {
353 		char *p;
354 		const char *env;
355 
356 		color = true;
357 		add_code = "32";
358 		del_code = "31";
359 		env = getenv("DIFFCOLORS");
360 		if (env != NULL && *env != '\0' && (p = strdup(env))) {
361 			add_code = p;
362 			strsep(&p, ":");
363 			if (p != NULL)
364 				del_code = p;
365 		}
366 	}
367 
368 #ifdef __OpenBSD__
369 	if (pledge("stdio rpath tmppath", NULL) == -1)
370 		err(2, "pledge");
371 #endif
372 
373 	/*
374 	 * Do sanity checks, fill in stb1 and stb2 and call the appropriate
375 	 * driver routine.  Both drivers use the contents of stb1 and stb2.
376 	 */
377 	if (argc != 2)
378 		usage();
379 	checked_regcomp(ignore_pats, &ignore_re);
380 	checked_regcomp(most_recent_pat, &most_recent_re);
381 	if (strcmp(argv[0], "-") == 0) {
382 		fstat(STDIN_FILENO, &stb1);
383 		gotstdin = 1;
384 	} else if (stat(argv[0], &stb1) != 0) {
385 		if (!Nflag || errno != ENOENT)
386 			err(2, "%s", argv[0]);
387 		dflags |= D_EMPTY1;
388 		memset(&stb1, 0, sizeof(struct stat));
389 	}
390 
391 	if (strcmp(argv[1], "-") == 0) {
392 		fstat(STDIN_FILENO, &stb2);
393 		gotstdin = 1;
394 	} else if (stat(argv[1], &stb2) != 0) {
395 		if (!Nflag || errno != ENOENT)
396 			err(2, "%s", argv[1]);
397 		dflags |= D_EMPTY2;
398 		memset(&stb2, 0, sizeof(stb2));
399 		stb2.st_mode = stb1.st_mode;
400 	}
401 
402 	if (dflags & D_EMPTY1 && dflags & D_EMPTY2){
403 		warn("%s", argv[0]);
404 		warn("%s", argv[1]);
405 		exit(2);
406 	}
407 
408 	if (stb1.st_mode == 0)
409 		stb1.st_mode = stb2.st_mode;
410 
411 	if (gotstdin && (S_ISDIR(stb1.st_mode) || S_ISDIR(stb2.st_mode)))
412 		errx(2, "can't compare - to a directory");
413 	set_argstr(oargv, argv);
414 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
415 		if (diff_format == D_IFDEF)
416 			errx(2, "-D option not supported with directories");
417 		diffdir(argv[0], argv[1], dflags);
418 	} else {
419 		if (S_ISDIR(stb1.st_mode)) {
420 			argv[0] = splice(argv[0], argv[1]);
421 			if (stat(argv[0], &stb1) == -1)
422 				err(2, "%s", argv[0]);
423 		}
424 		if (S_ISDIR(stb2.st_mode)) {
425 			argv[1] = splice(argv[1], argv[0]);
426 			if (stat(argv[1], &stb2) == -1)
427 				err(2, "%s", argv[1]);
428 		}
429 		print_status(diffreg(argv[0], argv[1], dflags, 1), argv[0],
430 		    argv[1], "");
431 	}
432 	exit(status);
433 }
434 
435 static void
436 checked_regcomp(char const *pattern, regex_t *comp)
437 {
438 	char buf[BUFSIZ];
439 	int error;
440 
441 	if (pattern == NULL)
442 		return;
443 
444 	error = regcomp(comp, pattern, REG_NEWLINE | REG_EXTENDED);
445 	if (error != 0) {
446 		regerror(error, comp, buf, sizeof(buf));
447 		if (*pattern != '\0')
448 			errx(2, "%s: %s", pattern, buf);
449 		else
450 			errx(2, "%s", buf);
451 	}
452 }
453 
454 static void
455 set_argstr(char **av, char **ave)
456 {
457 	size_t argsize;
458 	char **ap;
459 
460 	argsize = 4 + *ave - *av + 1;
461 	diffargs = xmalloc(argsize);
462 	strlcpy(diffargs, "diff", argsize);
463 	for (ap = av + 1; ap < ave; ap++) {
464 		if (strcmp(*ap, "--") != 0) {
465 			strlcat(diffargs, " ", argsize);
466 			strlcat(diffargs, *ap, argsize);
467 		}
468 	}
469 }
470 
471 /*
472  * Read in an excludes file and push each line.
473  */
474 static void
475 read_excludes_file(char *file)
476 {
477 	FILE *fp;
478 	char *buf, *pattern;
479 	size_t len;
480 
481 	if (strcmp(file, "-") == 0)
482 		fp = stdin;
483 	else if ((fp = fopen(file, "r")) == NULL)
484 		err(2, "%s", file);
485 	while ((buf = fgetln(fp, &len)) != NULL) {
486 		if (buf[len - 1] == '\n')
487 			len--;
488 		if ((pattern = strndup(buf, len)) == NULL)
489 			err(2, "xstrndup");
490 		push_excludes(pattern);
491 	}
492 	if (strcmp(file, "-") != 0)
493 		fclose(fp);
494 }
495 
496 /*
497  * Push a pattern onto the excludes list.
498  */
499 static void
500 push_excludes(char *pattern)
501 {
502 	struct excludes *entry;
503 
504 	entry = xmalloc(sizeof(*entry));
505 	entry->pattern = pattern;
506 	entry->next = excludes_list;
507 	excludes_list = entry;
508 }
509 
510 static void
511 push_ignore_pats(char *pattern)
512 {
513 	size_t len;
514 
515 	if (ignore_pats == NULL)
516 		ignore_pats = xstrdup(pattern);
517 	else {
518 		/* old + "|" + new + NUL */
519 		len = strlen(ignore_pats) + strlen(pattern) + 2;
520 		ignore_pats = xreallocarray(ignore_pats, 1, len);
521 		strlcat(ignore_pats, "|", len);
522 		strlcat(ignore_pats, pattern, len);
523 	}
524 }
525 
526 void
527 print_status(int val, char *path1, char *path2, const char *entry)
528 {
529 	if (label[0] != NULL)
530 		path1 = label[0];
531 	if (label[1] != NULL)
532 		path2 = label[1];
533 
534 	switch (val) {
535 	case D_BINARY:
536 		printf("Binary files %s%s and %s%s differ\n",
537 		    path1, entry, path2, entry);
538 		break;
539 	case D_DIFFER:
540 		if (diff_format == D_BRIEF)
541 			printf("Files %s%s and %s%s differ\n",
542 			    path1, entry, path2, entry);
543 		break;
544 	case D_SAME:
545 		if (sflag)
546 			printf("Files %s%s and %s%s are identical\n",
547 			    path1, entry, path2, entry);
548 		break;
549 	case D_MISMATCH1:
550 		printf("File %s%s is a directory while file %s%s is a regular file\n",
551 		    path1, entry, path2, entry);
552 		break;
553 	case D_MISMATCH2:
554 		printf("File %s%s is a regular file while file %s%s is a directory\n",
555 		    path1, entry, path2, entry);
556 		break;
557 	case D_SKIPPED1:
558 		printf("File %s%s is not a regular file or directory and was skipped\n",
559 		    path1, entry);
560 		break;
561 	case D_SKIPPED2:
562 		printf("File %s%s is not a regular file or directory and was skipped\n",
563 		    path2, entry);
564 		break;
565 	case D_ERROR:
566 		break;
567 	}
568 }
569 
570 static void
571 usage(void)
572 {
573 	(void)fprintf(stderr,
574 	    "usage: diff [-aBbdilpTtw] [-c | -e | -f | -n | -q | -u] [--ignore-case]\n"
575 	    "            [--no-ignore-case] [--normal] [--strip-trailing-cr] [--tabsize]\n"
576 	    "            [-I pattern] [-F pattern] [-L label] file1 file2\n"
577 	    "       diff [-aBbdilpTtw] [-I pattern] [-L label] [--ignore-case]\n"
578 	    "            [--no-ignore-case] [--normal] [--strip-trailing-cr] [--tabsize]\n"
579 	    "            [-F pattern] -C number file1 file2\n"
580 	    "       diff [-aBbdiltw] [-I pattern] [--ignore-case] [--no-ignore-case]\n"
581 	    "            [--normal] [--strip-trailing-cr] [--tabsize] -D string file1 file2\n"
582 	    "       diff [-aBbdilpTtw] [-I pattern] [-L label] [--ignore-case]\n"
583 	    "            [--no-ignore-case] [--normal] [--tabsize] [--strip-trailing-cr]\n"
584 	    "            [-F pattern] -U number file1 file2\n"
585 	    "       diff [-aBbdilNPprsTtw] [-c | -e | -f | -n | -q | -u] [--ignore-case]\n"
586 	    "            [--no-ignore-case] [--normal] [--tabsize] [-I pattern] [-L label]\n"
587 	    "            [-F pattern] [-S name] [-X file] [-x pattern] dir1 dir2\n"
588 	    "       diff [-aBbditwW] [--expand-tabs] [--ignore-all-blanks]\n"
589 	    "            [--ignore-blank-lines] [--ignore-case] [--minimal]\n"
590 	    "            [--no-ignore-file-name-case] [--strip-trailing-cr]\n"
591 	    "            [--suppress-common-lines] [--tabsize] [--text] [--width]\n"
592 	    "            -y | --side-by-side file1 file2\n");
593 
594 	exit(2);
595 }
596 
597 static void
598 conflicting_format(void)
599 {
600 
601 	fprintf(stderr, "error: conflicting output format options.\n");
602 	usage();
603 }
604 
605 static bool
606 do_color(void)
607 {
608 	const char *p, *p2;
609 
610 	switch (colorflag) {
611 	case COLORFLAG_AUTO:
612 		p = getenv("CLICOLOR");
613 		p2 = getenv("COLORTERM");
614 		if ((p != NULL && *p != '\0') || (p2 != NULL && *p2 != '\0'))
615 			return isatty(STDOUT_FILENO);
616 		break;
617 	case COLORFLAG_ALWAYS:
618 		return (true);
619 	case COLORFLAG_NEVER:
620 		return (false);
621 	}
622 
623 	return (false);
624 }
625 
626 static char *
627 splice(char *dir, char *path)
628 {
629 	char *tail, *buf;
630 	size_t dirlen;
631 
632 	dirlen = strlen(dir);
633 	while (dirlen != 0 && dir[dirlen - 1] == '/')
634 	    dirlen--;
635 	if ((tail = strrchr(path, '/')) == NULL)
636 		tail = path;
637 	else
638 		tail++;
639 	xasprintf(&buf, "%.*s/%s", (int)dirlen, dir, tail);
640 	return (buf);
641 }
642