xref: /openbsd-src/usr.bin/diff/diffdir.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: diffdir.c,v 1.32 2007/06/09 05:16:21 ray 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 1.32 2007/06/09 05:16:21 ray 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 #include "xmalloc.h"
43 
44 static int dircompare(const void *, const void *);
45 static int excluded(const char *);
46 static struct dirent **slurpdir(char *, char **, int);
47 static void diffit(struct dirent *, char *, size_t, char *, size_t);
48 
49 #define d_status	d_type		/* we need to store status for -l */
50 
51 /*
52  * Diff directory traversal. Will be called recursively if -r was specified.
53  */
54 void
55 diffdir(char *p1, char *p2)
56 {
57 	struct dirent **dirp1, **dirp2, **dp1, **dp2;
58 	struct dirent *dent1, *dent2;
59 	size_t dirlen1, dirlen2;
60 	char path1[MAXPATHLEN], path2[MAXPATHLEN];
61 	char *dirbuf1, *dirbuf2;
62 	int pos;
63 
64 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
65 	if (dirlen1 >= sizeof(path1) - 1) {
66 		warnx("%s: %s", p1, strerror(ENAMETOOLONG));
67 		status = 2;
68 		return;
69 	}
70 	if (path1[dirlen1 - 1] != '/') {
71 		path1[dirlen1++] = '/';
72 		path1[dirlen1] = '\0';
73 	}
74 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
75 	if (dirlen2 >= sizeof(path2) - 1) {
76 		warnx("%s: %s", p2, strerror(ENAMETOOLONG));
77 		status = 2;
78 		return;
79 	}
80 	if (path2[dirlen2 - 1] != '/') {
81 		path2[dirlen2++] = '/';
82 		path2[dirlen2] = '\0';
83 	}
84 
85 	/* get a list of the entries in each directory */
86 	dp1 = dirp1 = slurpdir(path1, &dirbuf1, Nflag + Pflag);
87 	dp2 = dirp2 = slurpdir(path2, &dirbuf2, Nflag);
88 	if (dirp1 == NULL || dirp2 == NULL)
89 		return;
90 
91 	/*
92 	 * If we were given a starting point, find it.
93 	 */
94 	if (start != NULL) {
95 		while (*dp1 != NULL && strcmp((*dp1)->d_name, start) < 0)
96 			dp1++;
97 		while (*dp2 != NULL && strcmp((*dp2)->d_name, start) < 0)
98 			dp2++;
99 	}
100 
101 	/*
102 	 * Iterate through the two directory lists, diffing as we go.
103 	 */
104 	while (*dp1 != NULL || *dp2 != NULL) {
105 		dent1 = *dp1;
106 		dent2 = *dp2;
107 
108 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
109 		    strcmp(dent1->d_name, dent2->d_name);
110 		if (pos == 0) {
111 			/* file exists in both dirs, diff it */
112 			diffit(dent1, path1, dirlen1, path2, dirlen2);
113 			dp1++;
114 			dp2++;
115 		} else if (pos < 0) {
116 			/* file only in first dir, only diff if -N */
117 			if (Nflag)
118 				diffit(dent1, path1, dirlen1, path2, dirlen2);
119 			else if (lflag)
120 				dent1->d_status |= D_ONLY;
121 			else
122 				print_only(path1, dirlen1, dent1->d_name);
123 			dp1++;
124 		} else {
125 			/* file only in second dir, only diff if -N or -P */
126 			if (Nflag || Pflag)
127 				diffit(dent2, path1, dirlen1, path2, dirlen2);
128 			else if (lflag)
129 				dent2->d_status |= D_ONLY;
130 			else
131 				print_only(path2, dirlen2, dent2->d_name);
132 			dp2++;
133 		}
134 	}
135 	if (lflag) {
136 		path1[dirlen1] = '\0';
137 		path2[dirlen2] = '\0';
138 		for (dp1 = dirp1; (dent1 = *dp1) != NULL; dp1++) {
139 			print_status(dent1->d_status, path1, path2,
140 			    dent1->d_name);
141 		}
142 		for (dp2 = dirp2; (dent2 = *dp2) != NULL; dp2++) {
143 			if (dent2->d_status == D_ONLY)
144 				print_status(dent2->d_status, path2, NULL,
145 				    dent2->d_name);
146 		}
147 	}
148 
149 	if (dirbuf1 != NULL) {
150 		xfree(dirp1);
151 		xfree(dirbuf1);
152 	}
153 	if (dirbuf2 != NULL) {
154 		xfree(dirp2);
155 		xfree(dirbuf2);
156 	}
157 }
158 
159 /*
160  * Read in a whole directory's worth of struct dirents, culling
161  * out the "excluded" ones.
162  * Returns an array of struct dirent *'s that point into the buffer
163  * returned via bufp.  Caller is responsible for free()ing both of these.
164  */
165 static struct dirent **
166 slurpdir(char *path, char **bufp, int enoentok)
167 {
168 	char *buf, *ebuf, *cp;
169 	size_t bufsize, have, need;
170 	long base;
171 	int fd, nbytes, entries;
172 	struct stat sb;
173 	struct dirent **dirlist, *dp;
174 
175 	*bufp = NULL;
176 	if ((fd = open(path, O_RDONLY, 0644)) == -1) {
177 		static struct dirent *dummy;
178 
179 		if (!enoentok || errno != ENOENT) {
180 			warn("%s", path);
181 			return (NULL);
182 		}
183 		return (&dummy);
184 	}
185 	if (fstat(fd, &sb) == -1) {
186 		warn("%s", path);
187 		close(fd);
188 		return (NULL);
189 	}
190 
191 	need = roundup(sb.st_blksize, sizeof(struct dirent));
192 	have = bufsize = roundup(MAX(sb.st_size, sb.st_blksize),
193 	    sizeof(struct dirent)) + need;
194 	ebuf = buf = xmalloc(bufsize);
195 
196 	do {
197 		if (have < need) {
198 		    bufsize += need;
199 		    have += need;
200 		    cp = xrealloc(buf, 1, bufsize);
201 		    ebuf = cp + (ebuf - buf);
202 		    buf = cp;
203 		}
204 		nbytes = getdirentries(fd, ebuf, have, &base);
205 		if (nbytes == -1) {
206 			warn("%s", path);
207 			xfree(buf);
208 			close(fd);
209 			return (NULL);
210 		}
211 		ebuf += nbytes;
212 		have -= nbytes;
213 	} while (nbytes != 0);
214 	close(fd);
215 
216 	/*
217 	 * We now have all the directory entries in our buffer.
218 	 * However, in order to easily sort them we need to convert
219 	 * the buffer into an array.
220 	 */
221 	for (entries = 0, cp = buf; cp < ebuf; ) {
222 		dp = (struct dirent *)cp;
223 		if (dp->d_fileno != 0)
224 			entries++;
225 		if (dp->d_reclen <= 0)
226 			break;
227 		cp += dp->d_reclen;
228 	}
229 	dirlist = xmalloc(sizeof(*dirlist) * (entries + 1));
230 	for (entries = 0, cp = buf; cp < ebuf; ) {
231 		dp = (struct dirent *)cp;
232 		if (dp->d_fileno != 0 && !excluded(dp->d_name)) {
233 			dp->d_status = 0;
234 			dirlist[entries++] = dp;
235 		}
236 		if (dp->d_reclen <= 0)
237 			break;
238 		cp += dp->d_reclen;
239 	}
240 	dirlist[entries] = NULL;
241 
242 	qsort(dirlist, entries, sizeof(struct dirent *), dircompare);
243 
244 	*bufp = buf;
245 	return (dirlist);
246 }
247 
248 /*
249  * Compare d_name in two dirent structures; for qsort(3).
250  */
251 static int
252 dircompare(const void *vp1, const void *vp2)
253 {
254 	struct dirent *dp1 = *((struct dirent **) vp1);
255 	struct dirent *dp2 = *((struct dirent **) vp2);
256 
257 	return (strcmp(dp1->d_name, dp2->d_name));
258 }
259 
260 /*
261  * Do the actual diff by calling either diffreg() or diffdir().
262  */
263 static void
264 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2)
265 {
266 	int flags = D_HEADER;
267 
268 	strlcpy(path1 + plen1, dp->d_name, MAXPATHLEN - plen1);
269 	if (stat(path1, &stb1) != 0) {
270 		if (!(Nflag || Pflag) || errno != ENOENT) {
271 			warn("%s", path1);
272 			return;
273 		}
274 		flags |= D_EMPTY1;
275 		memset(&stb1, 0, sizeof(stb1));
276 	}
277 
278 	strlcpy(path2 + plen2, dp->d_name, MAXPATHLEN - plen2);
279 	if (stat(path2, &stb2) != 0) {
280 		if (!Nflag || errno != ENOENT) {
281 			warn("%s", path2);
282 			return;
283 		}
284 		flags |= D_EMPTY2;
285 		memset(&stb2, 0, sizeof(stb2));
286 		stb2.st_mode = stb1.st_mode;
287 	}
288 	if (stb1.st_mode == 0)
289 		stb1.st_mode = stb2.st_mode;
290 
291 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
292 		if (rflag)
293 			diffdir(path1, path2);
294 		else if (lflag)
295 			dp->d_status |= D_COMMON;
296 		else
297 			printf("Common subdirectories: %s and %s\n",
298 			    path1, path2);
299 		return;
300 	}
301 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
302 		dp->d_status = D_SKIPPED1;
303 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
304 		dp->d_status = D_SKIPPED2;
305 	else
306 		dp->d_status = diffreg(path1, path2, flags);
307 	if (!lflag)
308 		print_status(dp->d_status, path1, path2, NULL);
309 }
310 
311 /*
312  * Exclude the given directory entry?
313  */
314 static int
315 excluded(const char *entry)
316 {
317 	struct excludes *excl;
318 
319 	/* always skip "." and ".." */
320 	if (entry[0] == '.' &&
321 	    (entry[1] == '\0' || (entry[1] == '.' && entry[2] == '\0')))
322 		return (1);
323 
324 	/* check excludes list */
325 	for (excl = excludes_list; excl != NULL; excl = excl->next)
326 		if (fnmatch(excl->pattern, entry, FNM_PATHNAME) == 0)
327 			return (1);
328 
329 	return (0);
330 }
331