xref: /openbsd-src/usr.bin/diff/diffdir.c (revision cf2525843d483a385de106a1361b2b9c18d96583)
1 /*	$OpenBSD: diffdir.c,v 1.30 2005/06/15 18:44:01 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 1.30 2005/06/15 18:44:01 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 #define d_status	d_type		/* we need to store status for -l */
49 
50 /*
51  * Diff directory traversal. Will be called recursively if -r was specified.
52  */
53 void
54 diffdir(char *p1, char *p2)
55 {
56 	struct dirent **dirp1, **dirp2, **dp1, **dp2;
57 	struct dirent *dent1, *dent2;
58 	size_t dirlen1, dirlen2;
59 	char path1[MAXPATHLEN], path2[MAXPATHLEN];
60 	char *dirbuf1, *dirbuf2;
61 	int pos;
62 
63 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
64 	if (dirlen1 >= sizeof(path1) - 1) {
65 		warnx("%s: %s", p1, strerror(ENAMETOOLONG));
66 		status = 2;
67 		return;
68 	}
69 	if (path1[dirlen1 - 1] != '/') {
70 		path1[dirlen1++] = '/';
71 		path1[dirlen1] = '\0';
72 	}
73 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
74 	if (dirlen2 >= sizeof(path2) - 1) {
75 		warnx("%s: %s", p2, strerror(ENAMETOOLONG));
76 		status = 2;
77 		return;
78 	}
79 	if (path2[dirlen2 - 1] != '/') {
80 		path2[dirlen2++] = '/';
81 		path2[dirlen2] = '\0';
82 	}
83 
84 	/* get a list of the entries in each directory */
85 	dp1 = dirp1 = slurpdir(path1, &dirbuf1, Nflag + Pflag);
86 	dp2 = dirp2 = slurpdir(path2, &dirbuf2, Nflag);
87 	if (dirp1 == NULL || dirp2 == NULL)
88 		return;
89 
90 	/*
91 	 * If we were given a starting point, find it.
92 	 */
93 	if (start != NULL) {
94 		while (*dp1 != NULL && strcmp((*dp1)->d_name, start) < 0)
95 			dp1++;
96 		while (*dp2 != NULL && strcmp((*dp2)->d_name, start) < 0)
97 			dp2++;
98 	}
99 
100 	/*
101 	 * Iterate through the two directory lists, diffing as we go.
102 	 */
103 	while (*dp1 != NULL || *dp2 != NULL) {
104 		dent1 = *dp1;
105 		dent2 = *dp2;
106 
107 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
108 		    strcmp(dent1->d_name, dent2->d_name);
109 		if (pos == 0) {
110 			/* file exists in both dirs, diff it */
111 			diffit(dent1, path1, dirlen1, path2, dirlen2);
112 			dp1++;
113 			dp2++;
114 		} else if (pos < 0) {
115 			/* file only in first dir, only diff if -N */
116 			if (Nflag)
117 				diffit(dent1, path1, dirlen1, path2, dirlen2);
118 			else if (lflag)
119 				dent1->d_status |= D_ONLY;
120 			else
121 				print_only(path1, dirlen1, dent1->d_name);
122 			dp1++;
123 		} else {
124 			/* file only in second dir, only diff if -N or -P */
125 			if (Nflag || Pflag)
126 				diffit(dent2, path1, dirlen1, path2, dirlen2);
127 			else if (lflag)
128 				dent2->d_status |= D_ONLY;
129 			else
130 				print_only(path2, dirlen2, dent2->d_name);
131 			dp2++;
132 		}
133 	}
134 	if (lflag) {
135 		path1[dirlen1] = '\0';
136 		path2[dirlen2] = '\0';
137 		for (dp1 = dirp1; (dent1 = *dp1) != NULL; dp1++) {
138 			print_status(dent1->d_status, path1, path2,
139 			    dent1->d_name);
140 		}
141 		for (dp2 = dirp2; (dent2 = *dp2) != NULL; dp2++) {
142 			if (dent2->d_status == D_ONLY)
143 				print_status(dent2->d_status, path2, NULL,
144 				    dent2->d_name);
145 		}
146 	}
147 
148 	if (dirbuf1 != NULL) {
149 		free(dirp1);
150 		free(dirbuf1);
151 	}
152 	if (dirbuf2 != NULL) {
153 		free(dirp2);
154 		free(dirbuf2);
155 	}
156 }
157 
158 /*
159  * Read in a whole directory's worth of struct dirents, culling
160  * out the "excluded" ones.
161  * Returns an array of struct dirent *'s that point into the buffer
162  * returned via bufp.  Caller is responsible for free()ing both of these.
163  */
164 static struct dirent **
165 slurpdir(char *path, char **bufp, int enoentok)
166 {
167 	char *buf, *ebuf, *cp;
168 	size_t bufsize, have, need;
169 	long base;
170 	int fd, nbytes, entries;
171 	struct stat sb;
172 	struct dirent **dirlist, *dp;
173 
174 	*bufp = NULL;
175 	if ((fd = open(path, O_RDONLY, 0644)) == -1) {
176 		static struct dirent *dummy;
177 
178 		if (!enoentok || errno != ENOENT) {
179 			warn("%s", path);
180 			return (NULL);
181 		}
182 		return (&dummy);
183 	}
184 	if (fstat(fd, &sb) == -1) {
185 		warn("%s", path);
186 		close(fd);
187 		return (NULL);
188 	}
189 
190 	need = roundup(sb.st_blksize, sizeof(struct dirent));
191 	have = bufsize = roundup(MAX(sb.st_size, sb.st_blksize),
192 	    sizeof(struct dirent)) + need;
193 	ebuf = buf = emalloc(bufsize);
194 
195 	do {
196 		if (have < need) {
197 		    bufsize += need;
198 		    have += need;
199 		    cp = erealloc(buf, bufsize);
200 		    ebuf = cp + (ebuf - buf);
201 		    buf = cp;
202 		}
203 		nbytes = getdirentries(fd, ebuf, have, &base);
204 		if (nbytes == -1) {
205 			warn("%s", path);
206 			free(buf);
207 			close(fd);
208 			return (NULL);
209 		}
210 		ebuf += nbytes;
211 		have -= nbytes;
212 	} while (nbytes != 0);
213 	close(fd);
214 
215 	/*
216 	 * We now have all the directory entries in our buffer.
217 	 * However, in order to easily sort them we need to convert
218 	 * the buffer into an array.
219 	 */
220 	for (entries = 0, cp = buf; cp < ebuf; ) {
221 		dp = (struct dirent *)cp;
222 		if (dp->d_fileno != 0)
223 			entries++;
224 		if (dp->d_reclen <= 0)
225 			break;
226 		cp += dp->d_reclen;
227 	}
228 	dirlist = emalloc(sizeof(struct dirent *) * (entries + 1));
229 	for (entries = 0, cp = buf; cp < ebuf; ) {
230 		dp = (struct dirent *)cp;
231 		if (dp->d_fileno != 0 && !excluded(dp->d_name)) {
232 			dp->d_status = 0;
233 			dirlist[entries++] = dp;
234 		}
235 		if (dp->d_reclen <= 0)
236 			break;
237 		cp += dp->d_reclen;
238 	}
239 	dirlist[entries] = NULL;
240 
241 	qsort(dirlist, entries, sizeof(struct dirent *), dircompare);
242 
243 	*bufp = buf;
244 	return (dirlist);
245 }
246 
247 /*
248  * Compare d_name in two dirent structures; for qsort(3).
249  */
250 static int
251 dircompare(const void *vp1, const void *vp2)
252 {
253 	struct dirent *dp1 = *((struct dirent **) vp1);
254 	struct dirent *dp2 = *((struct dirent **) vp2);
255 
256 	return (strcmp(dp1->d_name, dp2->d_name));
257 }
258 
259 /*
260  * Do the actual diff by calling either diffreg() or diffdir().
261  */
262 static void
263 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2)
264 {
265 	int flags = D_HEADER;
266 
267 	strlcpy(path1 + plen1, dp->d_name, MAXPATHLEN - plen1);
268 	if (stat(path1, &stb1) != 0) {
269 		if (!(Nflag || Pflag) || errno != ENOENT) {
270 			warn("%s", path1);
271 			return;
272 		}
273 		flags |= D_EMPTY1;
274 		memset(&stb1, 0, sizeof(stb1));
275 	}
276 
277 	strlcpy(path2 + plen2, dp->d_name, MAXPATHLEN - plen2);
278 	if (stat(path2, &stb2) != 0) {
279 		if (!Nflag || errno != ENOENT) {
280 			warn("%s", path2);
281 			return;
282 		}
283 		flags |= D_EMPTY2;
284 		memset(&stb2, 0, sizeof(stb2));
285 		stb2.st_mode = stb1.st_mode;
286 	}
287 	if (stb1.st_mode == 0)
288 		stb1.st_mode = stb2.st_mode;
289 
290 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
291 		if (rflag)
292 			diffdir(path1, path2);
293 		else if (lflag)
294 			dp->d_status |= D_COMMON;
295 		else
296 			printf("Common subdirectories: %s and %s\n",
297 			    path1, path2);
298 		return;
299 	}
300 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
301 		dp->d_status = D_SKIPPED1;
302 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
303 		dp->d_status = D_SKIPPED2;
304 	else
305 		dp->d_status = diffreg(path1, path2, flags);
306 	if (!lflag)
307 		print_status(dp->d_status, path1, path2, NULL);
308 }
309 
310 /*
311  * Exclude the given directory entry?
312  */
313 static int
314 excluded(const char *entry)
315 {
316 	struct excludes *excl;
317 
318 	/* always skip "." and ".." */
319 	if (entry[0] == '.' &&
320 	    (entry[1] == '\0' || (entry[1] == '.' && entry[2] == '\0')))
321 		return (1);
322 
323 	/* check excludes list */
324 	for (excl = excludes_list; excl != NULL; excl = excl->next)
325 		if (fnmatch(excl->pattern, entry, FNM_PATHNAME) == 0)
326 			return (1);
327 
328 	return (0);
329 }
330