xref: /freebsd/usr.bin/diff/diff.c (revision c439438675a4029cb1904109701aef88061e9401)
1  /*	$OpenBSD: diff.c,v 1.65 2015/12/29 19:04:46 gsoares 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 <getopt.h>
31  #include <stdlib.h>
32  #include <stdio.h>
33  #include <string.h>
34  #include <unistd.h>
35  #include <limits.h>
36  
37  #include "diff.h"
38  #include "xmalloc.h"
39  
40  int	 lflag, Nflag, Pflag, rflag, sflag, Tflag, cflag;
41  int	 diff_format, diff_context, status, ignore_file_case;
42  int	 tabsize = 8;
43  char	*start, *ifdefname, *diffargs, *label[2], *ignore_pats;
44  char	*group_format = NULL;
45  struct stat stb1, stb2;
46  struct excludes *excludes_list;
47  regex_t	 ignore_re;
48  
49  #define	OPTIONS	"0123456789aBbC:cdD:efHhI:iL:lnNPpqrS:sTtU:uwX:x:"
50  enum {
51  	OPT_TSIZE = CHAR_MAX + 1,
52  	OPT_STRIPCR,
53  	OPT_IGN_FN_CASE,
54  	OPT_NO_IGN_FN_CASE,
55  	OPT_NORMAL,
56  	OPT_HORIZON_LINES,
57  	OPT_CHANGED_GROUP_FORMAT,
58  };
59  
60  static struct option longopts[] = {
61  	{ "text",			no_argument,		0,	'a' },
62  	{ "ignore-space-change",	no_argument,		0,	'b' },
63  	{ "context",			optional_argument,	0,	'C' },
64  	{ "ifdef",			required_argument,	0,	'D' },
65  	{ "minimal",			no_argument,		0,	'd' },
66  	{ "ed",				no_argument,		0,	'e' },
67  	{ "forward-ed",			no_argument,		0,	'f' },
68  	{ "speed-large-files",		no_argument,		NULL,	'H' },
69  	{ "ignore-matching-lines",	required_argument,	0,	'I' },
70  	{ "ignore-case",		no_argument,		0,	'i' },
71  	{ "paginate",			no_argument,		NULL,	'l' },
72  	{ "label",			required_argument,	0,	'L' },
73  	{ "new-file",			no_argument,		0,	'N' },
74  	{ "rcs",			no_argument,		0,	'n' },
75  	{ "unidirectional-new-file",	no_argument,		0,	'P' },
76  	{ "show-c-function",		no_argument,		0,	'p' },
77  	{ "brief",			no_argument,		0,	'q' },
78  	{ "recursive",			no_argument,		0,	'r' },
79  	{ "report-identical-files",	no_argument,		0,	's' },
80  	{ "starting-file",		required_argument,	0,	'S' },
81  	{ "expand-tabs",		no_argument,		0,	't' },
82  	{ "initial-tab",		no_argument,		0,	'T' },
83  	{ "unified",			optional_argument,	0,	'U' },
84  	{ "ignore-all-space",		no_argument,		0,	'w' },
85  	{ "exclude",			required_argument,	0,	'x' },
86  	{ "exclude-from",		required_argument,	0,	'X' },
87  	{ "ignore-file-name-case",	no_argument,		NULL,	OPT_IGN_FN_CASE },
88  	{ "horizon-lines",		required_argument,	NULL,	OPT_HORIZON_LINES },
89  	{ "no-ignore-file-name-case",	no_argument,		NULL,	OPT_NO_IGN_FN_CASE },
90  	{ "normal",			no_argument,		NULL,	OPT_NORMAL },
91  	{ "strip-trailing-cr",		no_argument,		NULL,	OPT_STRIPCR },
92  	{ "tabsize",			optional_argument,	NULL,	OPT_TSIZE },
93  	{ "changed-group-format",	required_argument,	NULL,	OPT_CHANGED_GROUP_FORMAT},
94  	{ NULL,				0,			0,	'\0'}
95  };
96  
97  void usage(void) __dead2;
98  void push_excludes(char *);
99  void push_ignore_pats(char *);
100  void read_excludes_file(char *file);
101  void set_argstr(char **, char **);
102  
103  int
104  main(int argc, char **argv)
105  {
106  	const char *errstr = NULL;
107  	char *ep, **oargv;
108  	long  l;
109  	int   ch, dflags, lastch, gotstdin, prevoptind, newarg;
110  
111  	oargv = argv;
112  	gotstdin = 0;
113  	dflags = 0;
114  	lastch = '\0';
115  	prevoptind = 1;
116  	newarg = 1;
117  	diff_context = 3;
118  	diff_format = 0;
119  	while ((ch = getopt_long(argc, argv, OPTIONS, longopts, NULL)) != -1) {
120  		switch (ch) {
121  		case '0': case '1': case '2': case '3': case '4':
122  		case '5': case '6': case '7': case '8': case '9':
123  			if (newarg)
124  				usage();	/* disallow -[0-9]+ */
125  			else if (lastch == 'c' || lastch == 'u')
126  				diff_context = 0;
127  			else if (!isdigit(lastch) || diff_context > INT_MAX / 10)
128  				usage();
129  			diff_context = (diff_context * 10) + (ch - '0');
130  			break;
131  		case 'a':
132  			dflags |= D_FORCEASCII;
133  			break;
134  		case 'b':
135  			dflags |= D_FOLDBLANKS;
136  			break;
137  		case 'C':
138  		case 'c':
139  			cflag = 1;
140  			diff_format = D_CONTEXT;
141  			if (optarg != NULL) {
142  				l = strtol(optarg, &ep, 10);
143  				if (*ep != '\0' || l < 0 || l >= INT_MAX)
144  					usage();
145  				diff_context = (int)l;
146  			}
147  			break;
148  		case 'd':
149  			dflags |= D_MINIMAL;
150  			break;
151  		case 'D':
152  			diff_format = D_IFDEF;
153  			ifdefname = optarg;
154  			break;
155  		case 'e':
156  			diff_format = D_EDIT;
157  			break;
158  		case 'f':
159  			diff_format = D_REVERSE;
160  			break;
161  		case 'H':
162  			/* ignore but needed for compatibility with GNU diff */
163  			break;
164  		case 'h':
165  			/* silently ignore for backwards compatibility */
166  			break;
167  		case 'I':
168  			push_ignore_pats(optarg);
169  			break;
170  		case 'i':
171  			dflags |= D_IGNORECASE;
172  			break;
173  		case 'L':
174  			if (label[0] == NULL)
175  				label[0] = optarg;
176  			else if (label[1] == NULL)
177  				label[1] = optarg;
178  			else
179  				usage();
180  			break;
181  		case 'l':
182  			lflag = 1;
183  			break;
184  		case 'N':
185  			Nflag = 1;
186  			break;
187  		case 'n':
188  			diff_format = D_NREVERSE;
189  			break;
190  		case 'p':
191  			if (diff_format == 0)
192  				diff_format = D_CONTEXT;
193  			dflags |= D_PROTOTYPE;
194  			break;
195  		case 'P':
196  			Pflag = 1;
197  			break;
198  		case 'r':
199  			rflag = 1;
200  			break;
201  		case 'q':
202  			diff_format = D_BRIEF;
203  			break;
204  		case 'S':
205  			start = optarg;
206  			break;
207  		case 's':
208  			sflag = 1;
209  			break;
210  		case 'T':
211  			Tflag = 1;
212  			break;
213  		case 't':
214  			dflags |= D_EXPANDTABS;
215  			break;
216  		case 'U':
217  		case 'u':
218  			diff_format = D_UNIFIED;
219  			if (optarg != NULL) {
220  				l = strtol(optarg, &ep, 10);
221  				if (*ep != '\0' || l < 0 || l >= INT_MAX)
222  					usage();
223  				diff_context = (int)l;
224  			}
225  			break;
226  		case 'w':
227  			dflags |= D_IGNOREBLANKS;
228  			break;
229  		case 'X':
230  			read_excludes_file(optarg);
231  			break;
232  		case 'x':
233  			push_excludes(optarg);
234  			break;
235  		case OPT_CHANGED_GROUP_FORMAT:
236  			diff_format = D_GFORMAT;
237  			group_format = optarg;
238  			break;
239  		case OPT_HORIZON_LINES:
240  			break; /* XXX TODO for compatibility with GNU diff3 */
241  		case OPT_IGN_FN_CASE:
242  			ignore_file_case = 1;
243  			break;
244  		case OPT_NO_IGN_FN_CASE:
245  			ignore_file_case = 0;
246  			break;
247  		case OPT_NORMAL:
248  			diff_format = D_NORMAL;
249  			break;
250  		case OPT_TSIZE:
251  			tabsize = (int) strtonum(optarg, 1, INT_MAX, &errstr);
252  			if (errstr) {
253  				warnx("Invalid argument for tabsize");
254  				usage();
255  			}
256  			break;
257  		case OPT_STRIPCR:
258  			dflags |= D_STRIPCR;
259  			break;
260  		default:
261  			usage();
262  			break;
263  		}
264  		lastch = ch;
265  		newarg = optind != prevoptind;
266  		prevoptind = optind;
267  	}
268  	argc -= optind;
269  	argv += optind;
270  
271  #ifdef __OpenBSD__
272  	if (pledge("stdio rpath tmppath", NULL) == -1)
273  		err(2, "pledge");
274  #endif
275  
276  	/*
277  	 * Do sanity checks, fill in stb1 and stb2 and call the appropriate
278  	 * driver routine.  Both drivers use the contents of stb1 and stb2.
279  	 */
280  	if (argc != 2)
281  		usage();
282  	if (ignore_pats != NULL) {
283  		char buf[BUFSIZ];
284  		int error;
285  
286  		if ((error = regcomp(&ignore_re, ignore_pats,
287  				     REG_NEWLINE | REG_EXTENDED)) != 0) {
288  			regerror(error, &ignore_re, buf, sizeof(buf));
289  			if (*ignore_pats != '\0')
290  				errx(2, "%s: %s", ignore_pats, buf);
291  			else
292  				errx(2, "%s", buf);
293  		}
294  	}
295  	if (strcmp(argv[0], "-") == 0) {
296  		fstat(STDIN_FILENO, &stb1);
297  		gotstdin = 1;
298  	} else if (stat(argv[0], &stb1) != 0)
299  		err(2, "%s", argv[0]);
300  	if (strcmp(argv[1], "-") == 0) {
301  		fstat(STDIN_FILENO, &stb2);
302  		gotstdin = 1;
303  	} else if (stat(argv[1], &stb2) != 0)
304  		err(2, "%s", argv[1]);
305  	if (gotstdin && (S_ISDIR(stb1.st_mode) || S_ISDIR(stb2.st_mode)))
306  		errx(2, "can't compare - to a directory");
307  	set_argstr(oargv, argv);
308  	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
309  		if (diff_format == D_IFDEF)
310  			errx(2, "-D option not supported with directories");
311  		diffdir(argv[0], argv[1], dflags);
312  	} else {
313  		if (S_ISDIR(stb1.st_mode)) {
314  			argv[0] = splice(argv[0], argv[1]);
315  			if (stat(argv[0], &stb1) < 0)
316  				err(2, "%s", argv[0]);
317  		}
318  		if (S_ISDIR(stb2.st_mode)) {
319  			argv[1] = splice(argv[1], argv[0]);
320  			if (stat(argv[1], &stb2) < 0)
321  				err(2, "%s", argv[1]);
322  		}
323  		print_status(diffreg(argv[0], argv[1], dflags, 1), argv[0],
324  		    argv[1], "");
325  	}
326  	exit(status);
327  }
328  
329  void
330  set_argstr(char **av, char **ave)
331  {
332  	size_t argsize;
333  	char **ap;
334  
335  	argsize = 4 + *ave - *av + 1;
336  	diffargs = xmalloc(argsize);
337  	strlcpy(diffargs, "diff", argsize);
338  	for (ap = av + 1; ap < ave; ap++) {
339  		if (strcmp(*ap, "--") != 0) {
340  			strlcat(diffargs, " ", argsize);
341  			strlcat(diffargs, *ap, argsize);
342  		}
343  	}
344  }
345  
346  /*
347   * Read in an excludes file and push each line.
348   */
349  void
350  read_excludes_file(char *file)
351  {
352  	FILE *fp;
353  	char *buf, *pattern;
354  	size_t len;
355  
356  	if (strcmp(file, "-") == 0)
357  		fp = stdin;
358  	else if ((fp = fopen(file, "r")) == NULL)
359  		err(2, "%s", file);
360  	while ((buf = fgetln(fp, &len)) != NULL) {
361  		if (buf[len - 1] == '\n')
362  			len--;
363  		if ((pattern = strndup(buf, len)) == NULL)
364  			err(2, "xstrndup");
365  		push_excludes(pattern);
366  	}
367  	if (strcmp(file, "-") != 0)
368  		fclose(fp);
369  }
370  
371  /*
372   * Push a pattern onto the excludes list.
373   */
374  void
375  push_excludes(char *pattern)
376  {
377  	struct excludes *entry;
378  
379  	entry = xmalloc(sizeof(*entry));
380  	entry->pattern = pattern;
381  	entry->next = excludes_list;
382  	excludes_list = entry;
383  }
384  
385  void
386  push_ignore_pats(char *pattern)
387  {
388  	size_t len;
389  
390  	if (ignore_pats == NULL)
391  		ignore_pats = xstrdup(pattern);
392  	else {
393  		/* old + "|" + new + NUL */
394  		len = strlen(ignore_pats) + strlen(pattern) + 2;
395  		ignore_pats = xreallocarray(ignore_pats, 1, len);
396  		strlcat(ignore_pats, "|", len);
397  		strlcat(ignore_pats, pattern, len);
398  	}
399  }
400  
401  void
402  print_only(const char *path, size_t dirlen, const char *entry)
403  {
404  	if (dirlen > 1)
405  		dirlen--;
406  	printf("Only in %.*s: %s\n", (int)dirlen, path, entry);
407  }
408  
409  void
410  print_status(int val, char *path1, char *path2, const char *entry)
411  {
412  	switch (val) {
413  	case D_BINARY:
414  		printf("Binary files %s%s and %s%s differ\n",
415  		    path1, entry, path2, entry);
416  		break;
417  	case D_DIFFER:
418  		if (diff_format == D_BRIEF)
419  			printf("Files %s%s and %s%s differ\n",
420  			    path1, entry, path2, entry);
421  		break;
422  	case D_SAME:
423  		if (sflag)
424  			printf("Files %s%s and %s%s are identical\n",
425  			    path1, entry, path2, entry);
426  		break;
427  	case D_MISMATCH1:
428  		printf("File %s%s is a directory while file %s%s is a regular file\n",
429  		    path1, entry, path2, entry);
430  		break;
431  	case D_MISMATCH2:
432  		printf("File %s%s is a regular file while file %s%s is a directory\n",
433  		    path1, entry, path2, entry);
434  		break;
435  	case D_SKIPPED1:
436  		printf("File %s%s is not a regular file or directory and was skipped\n",
437  		    path1, entry);
438  		break;
439  	case D_SKIPPED2:
440  		printf("File %s%s is not a regular file or directory and was skipped\n",
441  		    path2, entry);
442  		break;
443  	}
444  }
445  
446  void
447  usage(void)
448  {
449  	(void)fprintf(stderr,
450  	    "usage: diff [-abdilpTtw] [-c | -e | -f | -n | -q | -u] [--ignore-case]\n"
451  	    "            [--no-ignore-case] [--normal] [--strip-trailing-cr] [--tabsize]\n"
452  	    "            [-I pattern] [-L label] file1 file2\n"
453  	    "       diff [-abdilpTtw] [-I pattern] [-L label] [--ignore-case]\n"
454  	    "            [--no-ignore-case] [--normal] [--strip-trailing-cr] [--tabsize]\n"
455  	    "            -C number file1 file2\n"
456  	    "       diff [-abdiltw] [-I pattern] [--ignore-case] [--no-ignore-case]\n"
457  	    "            [--normal] [--strip-trailing-cr] [--tabsize] -D string file1 file2\n"
458  	    "       diff [-abdilpTtw] [-I pattern] [-L label] [--ignore-case]\n"
459  	    "            [--no-ignore-case] [--normal] [--tabsize] [--strip-trailing-cr]\n"
460  	    "            -U number file1 file2\n"
461  	    "       diff [-abdilNPprsTtw] [-c | -e | -f | -n | -q | -u] [--ignore-case]\n"
462  	    "            [--no-ignore-case] [--normal] [--tabsize] [-I pattern] [-L label]\n"
463  	    "            [-S name] [-X file] [-x pattern] dir1 dir2\n");
464  
465  	exit(2);
466  }
467