xref: /freebsd/usr.bin/diff/diffdir.c (revision 6dfb9460caf3466b23b2a24c7ac91ebbb0747226)
1  /*	$OpenBSD: diffdir.c,v 1.45 2015/10/05 20:15:00 millert Exp $	*/
2  
3  /*
4   * Copyright (c) 2003, 2010 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 <dirent.h>
29  #include <err.h>
30  #include <errno.h>
31  #include <fnmatch.h>
32  #include <stdio.h>
33  #include <stdlib.h>
34  #include <string.h>
35  #include <limits.h>
36  
37  #include "diff.h"
38  
39  static int selectfile(const struct dirent *);
40  static void diffit(struct dirent *, char *, size_t, char *, size_t, int);
41  
42  #define d_status	d_type		/* we need to store status for -l */
43  
44  /*
45   * Diff directory traversal. Will be called recursively if -r was specified.
46   */
47  void
48  diffdir(char *p1, char *p2, int flags)
49  {
50  	struct dirent *dent1, **dp1, **edp1, **dirp1 = NULL;
51  	struct dirent *dent2, **dp2, **edp2, **dirp2 = NULL;
52  	size_t dirlen1, dirlen2;
53  	char path1[PATH_MAX], path2[PATH_MAX];
54  	int pos;
55  
56  	edp1 = edp2 = NULL;
57  
58  	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
59  	if (dirlen1 >= sizeof(path1) - 1) {
60  		warnc(ENAMETOOLONG, "%s", p1);
61  		status = 2;
62  		return;
63  	}
64  	if (path1[dirlen1 - 1] != '/') {
65  		path1[dirlen1++] = '/';
66  		path1[dirlen1] = '\0';
67  	}
68  	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
69  	if (dirlen2 >= sizeof(path2) - 1) {
70  		warnc(ENAMETOOLONG, "%s", p2);
71  		status = 2;
72  		return;
73  	}
74  	if (path2[dirlen2 - 1] != '/') {
75  		path2[dirlen2++] = '/';
76  		path2[dirlen2] = '\0';
77  	}
78  
79  	/*
80  	 * Get a list of entries in each directory, skipping "excluded" files
81  	 * and sorting alphabetically.
82  	 */
83  	pos = scandir(path1, &dirp1, selectfile, alphasort);
84  	if (pos == -1) {
85  		if (errno == ENOENT && (Nflag || Pflag)) {
86  			pos = 0;
87  		} else {
88  			warn("%s", path1);
89  			goto closem;
90  		}
91  	}
92  	dp1 = dirp1;
93  	edp1 = dirp1 + pos;
94  
95  	pos = scandir(path2, &dirp2, selectfile, alphasort);
96  	if (pos == -1) {
97  		if (errno == ENOENT && Nflag) {
98  			pos = 0;
99  		} else {
100  			warn("%s", path2);
101  			goto closem;
102  		}
103  	}
104  	dp2 = dirp2;
105  	edp2 = dirp2 + pos;
106  
107  	/*
108  	 * If we were given a starting point, find it.
109  	 */
110  	if (start != NULL) {
111  		while (dp1 != edp1 && strcmp((*dp1)->d_name, start) < 0)
112  			dp1++;
113  		while (dp2 != edp2 && strcmp((*dp2)->d_name, start) < 0)
114  			dp2++;
115  	}
116  
117  	/*
118  	 * Iterate through the two directory lists, diffing as we go.
119  	 */
120  	while (dp1 != edp1 || dp2 != edp2) {
121  		dent1 = dp1 != edp1 ? *dp1 : NULL;
122  		dent2 = dp2 != edp2 ? *dp2 : NULL;
123  
124  		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
125  		    ignore_file_case ? strcasecmp(dent1->d_name, dent2->d_name) :
126  		    strcmp(dent1->d_name, dent2->d_name) ;
127  		if (pos == 0) {
128  			/* file exists in both dirs, diff it */
129  			diffit(dent1, path1, dirlen1, path2, dirlen2, flags);
130  			dp1++;
131  			dp2++;
132  		} else if (pos < 0) {
133  			/* file only in first dir, only diff if -N */
134  			if (Nflag)
135  				diffit(dent1, path1, dirlen1, path2, dirlen2,
136  				    flags);
137  			else
138  				print_only(path1, dirlen1, dent1->d_name);
139  			dp1++;
140  		} else {
141  			/* file only in second dir, only diff if -N or -P */
142  			if (Nflag || Pflag)
143  				diffit(dent2, path1, dirlen1, path2, dirlen2,
144  				    flags);
145  			else
146  				print_only(path2, dirlen2, dent2->d_name);
147  			dp2++;
148  		}
149  	}
150  
151  closem:
152  	if (dirp1 != NULL) {
153  		for (dp1 = dirp1; dp1 < edp1; dp1++)
154  			free(*dp1);
155  		free(dirp1);
156  	}
157  	if (dirp2 != NULL) {
158  		for (dp2 = dirp2; dp2 < edp2; dp2++)
159  			free(*dp2);
160  		free(dirp2);
161  	}
162  }
163  
164  /*
165   * Do the actual diff by calling either diffreg() or diffdir().
166   */
167  static void
168  diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
169      int flags)
170  {
171  	flags |= D_HEADER;
172  	strlcpy(path1 + plen1, dp->d_name, PATH_MAX - plen1);
173  	if (stat(path1, &stb1) != 0) {
174  		if (!(Nflag || Pflag) || errno != ENOENT) {
175  			warn("%s", path1);
176  			return;
177  		}
178  		flags |= D_EMPTY1;
179  		memset(&stb1, 0, sizeof(stb1));
180  	}
181  
182  	strlcpy(path2 + plen2, dp->d_name, PATH_MAX - plen2);
183  	if (stat(path2, &stb2) != 0) {
184  		if (!Nflag || errno != ENOENT) {
185  			warn("%s", path2);
186  			return;
187  		}
188  		flags |= D_EMPTY2;
189  		memset(&stb2, 0, sizeof(stb2));
190  		stb2.st_mode = stb1.st_mode;
191  	}
192  	if (stb1.st_mode == 0)
193  		stb1.st_mode = stb2.st_mode;
194  
195  	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
196  		if (rflag)
197  			diffdir(path1, path2, flags);
198  		else
199  			printf("Common subdirectories: %s and %s\n",
200  			    path1, path2);
201  		return;
202  	}
203  	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
204  		dp->d_status = D_SKIPPED1;
205  	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
206  		dp->d_status = D_SKIPPED2;
207  	else
208  		dp->d_status = diffreg(path1, path2, flags, 0);
209  	print_status(dp->d_status, path1, path2, "");
210  }
211  
212  /*
213   * Returns 1 if the directory entry should be included in the
214   * diff, else 0.  Checks the excludes list.
215   */
216  static int
217  selectfile(const struct dirent *dp)
218  {
219  	struct excludes *excl;
220  
221  	if (dp->d_fileno == 0)
222  		return (0);
223  
224  	/* always skip "." and ".." */
225  	if (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' ||
226  	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
227  		return (0);
228  
229  	/* check excludes list */
230  	for (excl = excludes_list; excl != NULL; excl = excl->next)
231  		if (fnmatch(excl->pattern, dp->d_name, FNM_PATHNAME) == 0)
232  			return (0);
233  
234  	return (1);
235  }
236