xref: /openbsd-src/usr.bin/diff/diffdir.c (revision aeb82612035e635c909e64ee78ff8209bfb3bf4a)
1 /*	$OpenBSD: diffdir.c,v 1.20 2003/07/06 22:02:36 millert 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 #ifndef lint
24 static const char rcsid[] = "$OpenBSD: diffdir.c,v 1.20 2003/07/06 22:02:36 millert Exp $";
25 #endif /* not lint */
26 
27 #include <sys/param.h>
28 #include <sys/stat.h>
29 
30 #include <dirent.h>
31 #include <err.h>
32 #include <errno.h>
33 #include <fcntl.h>
34 #include <fnmatch.h>
35 #include <paths.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <unistd.h>
40 
41 #include "diff.h"
42 
43 static int dircompare(const void *, const void *);
44 static int excluded(const char *);
45 static struct dirent **slurpdir(char *, char **, int);
46 static void diffit(struct dirent *, char *, size_t, char *, size_t);
47 
48 /*
49  * Diff directory traveral. Will be called recursively if -r was specified.
50  */
51 void
52 diffdir(char *p1, char *p2)
53 {
54 	struct dirent **dirp1, **dirp2, **dp1, **dp2;
55 	struct dirent *dent1, *dent2;
56 	size_t dirlen1, dirlen2;
57 	char path1[MAXPATHLEN], path2[MAXPATHLEN];
58 	char *dirbuf1, *dirbuf2;
59 	int pos;
60 
61 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
62 	if (dirlen1 >= sizeof(path1) - 1) {
63 		warnx("%s: %s", p1, strerror(ENAMETOOLONG));
64 		status = 2;
65 		return;
66 	}
67 	if (path1[dirlen1 - 1] != '/') {
68 		path1[dirlen1++] = '/';
69 		path1[dirlen1] = '\0';
70 	}
71 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
72 	if (dirlen2 >= sizeof(path2) - 1) {
73 		warnx("%s: %s", p2, strerror(ENAMETOOLONG));
74 		status = 2;
75 		return;
76 	}
77 	if (path2[dirlen2 - 1] != '/') {
78 		path2[dirlen2++] = '/';
79 		path2[dirlen2] = '\0';
80 	}
81 
82 	/* get a list of the entries in each directory */
83 	dp1 = dirp1 = slurpdir(path1, &dirbuf1, Nflag + Pflag);
84 	dp2 = dirp2 = slurpdir(path2, &dirbuf2, Nflag);
85 	if (dirp1 == NULL || dirp2 == NULL)
86 		return;
87 
88 	/*
89 	 * If we were given a starting point, find it.
90 	 */
91 	if (start != NULL) {
92 		while (*dp1 != NULL && strcmp((*dp1)->d_name, start) < 0)
93 			dp1++;
94 		while (*dp2 != NULL && strcmp((*dp2)->d_name, start) < 0)
95 			dp2++;
96 	}
97 
98 	/*
99 	 * Iterate through the two directory lists, diffing as we go.
100 	 */
101 	while (*dp1 != NULL || *dp2 != NULL) {
102 		dent1 = *dp1;
103 		dent2 = *dp2;
104 
105 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
106 		    strcmp(dent1->d_name, dent2->d_name);
107 		if (pos == 0) {
108 			/* file exists in both dirs, diff it */
109 			diffit(dent1, path1, dirlen1, path2, dirlen2);
110 			dp1++;
111 			dp2++;
112 		} else if (pos < 0) {
113 			/* file only in first dir, only diff if -N */
114 			if (Nflag)
115 				diffit(dent1, path1, dirlen1, path2, dirlen2);
116 			else if (format == D_NORMAL || format == D_CONTEXT ||
117 			    format == D_UNIFIED)
118 				/* XXX GNU diff always prints this XXX */
119 				printf("Only in %.*s: %s\n", (int)(dirlen1 - 1),
120 				    path1, dent1->d_name);
121 			dp1++;
122 		} else {
123 			/* file only in second dir, only diff if -N or -P */
124 			if (Nflag || Pflag)
125 				diffit(dent2, path1, dirlen1, path2, dirlen2);
126 			else if (format == D_NORMAL || format == D_CONTEXT ||
127 			    format == D_UNIFIED)
128 				/* XXX GNU diff always prints this XXX */
129 				printf("Only in %.*s: %s\n", (int)(dirlen2 - 1),
130 				    path2, dent2->d_name);
131 			dp2++;
132 		}
133 	}
134 
135 	if (dirbuf1 != NULL) {
136 		free(dirp1);
137 		free(dirbuf1);
138 	}
139 	if (dirbuf2 != NULL) {
140 		free(dirp2);
141 		free(dirbuf2);
142 	}
143 }
144 
145 /*
146  * Read in a whole directory's worth of struct dirents, culling
147  * out the "excluded" ones.
148  * Returns an array of struct dirent *'s that point into the buffer
149  * returned via bufp.  Caller is responsible for free()ing both of these.
150  */
151 static struct dirent **
152 slurpdir(char *path, char **bufp, int enoentok)
153 {
154 	char *buf, *ebuf, *cp;
155 	size_t bufsize;
156 	long base;
157 	int fd, nbytes, entries;
158 	struct stat sb;
159 	struct dirent **dirlist, *dp;
160 
161 	*bufp = NULL;
162 	if ((fd = open(path, O_RDONLY, 0644)) == -1) {
163 		static struct dirent *dummy;
164 
165 		if (!enoentok || errno != ENOENT) {
166 			warn("%s", path);
167 			return (NULL);
168 		}
169 		return (&dummy);
170 	}
171 	fstat(fd, &sb);
172 
173 	bufsize = sb.st_size;
174 	if (bufsize < sb.st_blksize)
175 		bufsize = sb.st_blksize;
176 	buf = emalloc(bufsize);
177 
178 	nbytes = getdirentries(fd, buf, bufsize, &base);
179 	if (nbytes <= 0) {
180 		free(buf);
181 		warn("%s", path);
182 		return (NULL);
183 	}
184 	ebuf = buf + nbytes;
185 	close(fd);
186 
187 	/*
188 	 * We now have all the directory entries in our buffer.
189 	 * However, in order to easily sort them we need to convert
190 	 * the buffer into an array.
191 	 */
192 	for (entries = 0, cp = buf; cp < ebuf; ) {
193 		dp = (struct dirent *)cp;
194 		if (dp->d_fileno != 0 && dp->d_type != DT_WHT)
195 			entries++;
196 		if (dp->d_reclen <= 0)
197 			break;
198 		cp += dp->d_reclen;
199 	}
200 	dirlist = emalloc(sizeof(struct dirent *) * (entries + 1));
201 	for (entries = 0, cp = buf; cp < ebuf; ) {
202 		dp = (struct dirent *)cp;
203 		if (dp->d_fileno != 0 && dp->d_type != DT_WHT &&
204 		    !excluded(dp->d_name))
205 			dirlist[entries++] = dp;
206 		if (dp->d_reclen <= 0)
207 			break;
208 		cp += dp->d_reclen;
209 	}
210 	dirlist[entries] = NULL;
211 
212 	qsort(dirlist, entries, sizeof(struct dir *), dircompare);
213 
214 	*bufp = buf;
215 	return (dirlist);
216 }
217 
218 /*
219  * Compare d_name in two dirent structures; for qsort(3).
220  */
221 static int
222 dircompare(const void *vp1, const void *vp2)
223 {
224 	struct dirent *dp1 = *((struct dirent **) vp1);
225 	struct dirent *dp2 = *((struct dirent **) vp2);
226 
227 	return (strcmp(dp1->d_name, dp2->d_name));
228 }
229 
230 /*
231  * Do the actual diff by calling either diffreg() or diffdir().
232  */
233 static void
234 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2)
235 {
236 	int flags = D_HEADER;
237 
238 	strlcpy(path1 + plen1, dp->d_name, MAXPATHLEN - plen1);
239 	if (stat(path1, &stb1) != 0) {
240 		if (!(Nflag || Pflag) || errno != ENOENT) {
241 			warn("%s", path1);
242 			return;
243 		}
244 		flags |= D_EMPTY1;
245 		memset(&stb1, 0, sizeof(stb1));
246 	}
247 
248 	strlcpy(path2 + plen2, dp->d_name, MAXPATHLEN - plen2);
249 	if (stat(path2, &stb2) != 0) {
250 		if (!Nflag || errno != ENOENT) {
251 			warn("%s", path2);
252 			return;
253 		}
254 		flags |= D_EMPTY2;
255 		memset(&stb2, 0, sizeof(stb2));
256 		stb2.st_mode = stb1.st_mode;
257 	}
258 	if (stb1.st_mode == 0)
259 		stb1.st_mode = stb2.st_mode;
260 
261 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
262 		if (rflag)
263 			diffdir(path1, path2);
264 		else if (format != D_EDIT)
265 			/* XXX GNU diff always prints this for dirs XXX */
266 			printf("Common subdirectories: %s and %s\n",
267 			    path1, path2);
268 		return;
269 	}
270 	diffreg(path1, path2, flags);
271 }
272 
273 /*
274  * Exclude the given directory entry?
275  */
276 static int
277 excluded(const char *entry)
278 {
279 	struct excludes *excl;
280 
281 	/* always skip "." and ".." */
282 	if (entry[0] == '.' &&
283 	    (entry[1] == '\0' || (entry[1] == '.' && entry[2] == '\0')))
284 		return (1);
285 
286 	/* check excludes list */
287 	for (excl = excludes_list; excl != NULL; excl = excl->next)
288 		if (fnmatch(excl->pattern, entry, FNM_PATHNAME) == 0)
289 			return (1);
290 
291 	return (0);
292 }
293