xref: /openbsd-src/usr.bin/diff/diffdir.c (revision 2821fdb080fdc801ba67bdf2837f5e164f3a2926)
1 /*	$OpenBSD: diffdir.c,v 1.35 2009/10/27 23:59:37 deraadt 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/param.h>
24 #include <sys/stat.h>
25 
26 #include <dirent.h>
27 #include <err.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <fnmatch.h>
31 #include <paths.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <unistd.h>
36 
37 #include "diff.h"
38 #include "xmalloc.h"
39 
40 static int dircompare(const void *, const void *);
41 static int excluded(const char *);
42 static struct dirent **slurpdir(char *, char **, int);
43 static void diffit(struct dirent *, char *, size_t, char *, size_t, int);
44 
45 #define d_status	d_type		/* we need to store status for -l */
46 
47 /*
48  * Diff directory traversal. Will be called recursively if -r was specified.
49  */
50 void
51 diffdir(char *p1, char *p2, int flags)
52 {
53 	struct dirent **dirp1, **dirp2, **dp1, **dp2;
54 	struct dirent *dent1, *dent2;
55 	size_t dirlen1, dirlen2;
56 	char path1[MAXPATHLEN], path2[MAXPATHLEN];
57 	char *dirbuf1, *dirbuf2;
58 	int pos;
59 
60 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
61 	if (dirlen1 >= sizeof(path1) - 1) {
62 		warnx("%s: %s", p1, strerror(ENAMETOOLONG));
63 		status = 2;
64 		return;
65 	}
66 	if (path1[dirlen1 - 1] != '/') {
67 		path1[dirlen1++] = '/';
68 		path1[dirlen1] = '\0';
69 	}
70 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
71 	if (dirlen2 >= sizeof(path2) - 1) {
72 		warnx("%s: %s", p2, strerror(ENAMETOOLONG));
73 		status = 2;
74 		return;
75 	}
76 	if (path2[dirlen2 - 1] != '/') {
77 		path2[dirlen2++] = '/';
78 		path2[dirlen2] = '\0';
79 	}
80 
81 	/* get a list of the entries in each directory */
82 	dp1 = dirp1 = slurpdir(path1, &dirbuf1, Nflag + Pflag);
83 	dp2 = dirp2 = slurpdir(path2, &dirbuf2, Nflag);
84 	if (dirp1 == NULL || dirp2 == NULL)
85 		return;
86 
87 	/*
88 	 * If we were given a starting point, find it.
89 	 */
90 	if (start != NULL) {
91 		while (*dp1 != NULL && strcmp((*dp1)->d_name, start) < 0)
92 			dp1++;
93 		while (*dp2 != NULL && strcmp((*dp2)->d_name, start) < 0)
94 			dp2++;
95 	}
96 
97 	/*
98 	 * Iterate through the two directory lists, diffing as we go.
99 	 */
100 	while (*dp1 != NULL || *dp2 != NULL) {
101 		dent1 = *dp1;
102 		dent2 = *dp2;
103 
104 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
105 		    strcmp(dent1->d_name, dent2->d_name);
106 		if (pos == 0) {
107 			/* file exists in both dirs, diff it */
108 			diffit(dent1, path1, dirlen1, path2, dirlen2, flags);
109 			dp1++;
110 			dp2++;
111 		} else if (pos < 0) {
112 			/* file only in first dir, only diff if -N */
113 			if (Nflag)
114 				diffit(dent1, path1, dirlen1, path2, dirlen2,
115 				    flags);
116 			else if (lflag)
117 				dent1->d_status |= D_ONLY;
118 			else
119 				print_only(path1, dirlen1, dent1->d_name);
120 			dp1++;
121 		} else {
122 			/* file only in second dir, only diff if -N or -P */
123 			if (Nflag || Pflag)
124 				diffit(dent2, path1, dirlen1, path2, dirlen2,
125 				    flags);
126 			else if (lflag)
127 				dent2->d_status |= D_ONLY;
128 			else
129 				print_only(path2, dirlen2, dent2->d_name);
130 			dp2++;
131 		}
132 	}
133 	if (lflag) {
134 		path1[dirlen1] = '\0';
135 		path2[dirlen2] = '\0';
136 		for (dp1 = dirp1; (dent1 = *dp1) != NULL; dp1++) {
137 			print_status(dent1->d_status, path1, path2,
138 			    dent1->d_name);
139 		}
140 		for (dp2 = dirp2; (dent2 = *dp2) != NULL; dp2++) {
141 			if (dent2->d_status == D_ONLY)
142 				print_status(dent2->d_status, path2, NULL,
143 				    dent2->d_name);
144 		}
145 	}
146 
147 	if (dirbuf1 != NULL) {
148 		xfree(dirp1);
149 		xfree(dirbuf1);
150 	}
151 	if (dirbuf2 != NULL) {
152 		xfree(dirp2);
153 		xfree(dirbuf2);
154 	}
155 }
156 
157 /*
158  * Read in a whole directory's worth of struct dirents, culling
159  * out the "excluded" ones.
160  * Returns an array of struct dirent *'s that point into the buffer
161  * returned via bufp.  Caller is responsible for free()ing both of these.
162  */
163 static struct dirent **
164 slurpdir(char *path, char **bufp, int enoentok)
165 {
166 	char *buf, *ebuf, *cp;
167 	size_t bufsize, have, need;
168 	long base;
169 	int fd, nbytes, entries;
170 	struct stat sb;
171 	struct dirent **dirlist, *dp;
172 
173 	*bufp = NULL;
174 	if ((fd = open(path, O_RDONLY, 0644)) == -1) {
175 		static struct dirent *dummy;
176 
177 		if (!enoentok || errno != ENOENT) {
178 			warn("%s", path);
179 			return (NULL);
180 		}
181 		return (&dummy);
182 	}
183 	if (fstat(fd, &sb) == -1) {
184 		warn("%s", path);
185 		close(fd);
186 		return (NULL);
187 	}
188 
189 	need = roundup(sb.st_blksize, sizeof(struct dirent));
190 	have = bufsize = roundup(MAX(sb.st_size, sb.st_blksize),
191 	    sizeof(struct dirent)) + need;
192 	ebuf = buf = xmalloc(bufsize);
193 
194 	do {
195 		if (have < need) {
196 		    bufsize += need;
197 		    have += need;
198 		    cp = xrealloc(buf, 1, bufsize);
199 		    ebuf = cp + (ebuf - buf);
200 		    buf = cp;
201 		}
202 		nbytes = getdirentries(fd, ebuf, have, &base);
203 		if (nbytes == -1) {
204 			warn("%s", path);
205 			xfree(buf);
206 			close(fd);
207 			return (NULL);
208 		}
209 		ebuf += nbytes;
210 		have -= nbytes;
211 	} while (nbytes != 0);
212 	close(fd);
213 
214 	/*
215 	 * We now have all the directory entries in our buffer.
216 	 * However, in order to easily sort them we need to convert
217 	 * the buffer into an array.
218 	 */
219 	for (entries = 0, cp = buf; cp < ebuf; ) {
220 		dp = (struct dirent *)cp;
221 		if (dp->d_fileno != 0)
222 			entries++;
223 		if (dp->d_reclen <= 0)
224 			break;
225 		cp += dp->d_reclen;
226 	}
227 	dirlist = xcalloc(sizeof(*dirlist), entries + 1);
228 	for (entries = 0, cp = buf; cp < ebuf; ) {
229 		dp = (struct dirent *)cp;
230 		if (dp->d_fileno != 0 && !excluded(dp->d_name)) {
231 			dp->d_status = 0;
232 			dirlist[entries++] = dp;
233 		}
234 		if (dp->d_reclen <= 0)
235 			break;
236 		cp += dp->d_reclen;
237 	}
238 	dirlist[entries] = NULL;
239 
240 	qsort(dirlist, entries, sizeof(struct dirent *), dircompare);
241 
242 	*bufp = buf;
243 	return (dirlist);
244 }
245 
246 /*
247  * Compare d_name in two dirent structures; for qsort(3).
248  */
249 static int
250 dircompare(const void *vp1, const void *vp2)
251 {
252 	struct dirent *dp1 = *((struct dirent **) vp1);
253 	struct dirent *dp2 = *((struct dirent **) vp2);
254 
255 	return (strcmp(dp1->d_name, dp2->d_name));
256 }
257 
258 /*
259  * Do the actual diff by calling either diffreg() or diffdir().
260  */
261 static void
262 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
263     int flags)
264 {
265 	flags |= D_HEADER;
266 	strlcpy(path1 + plen1, dp->d_name, MAXPATHLEN - plen1);
267 	if (stat(path1, &stb1) != 0) {
268 		if (!(Nflag || Pflag) || errno != ENOENT) {
269 			warn("%s", path1);
270 			return;
271 		}
272 		flags |= D_EMPTY1;
273 		memset(&stb1, 0, sizeof(stb1));
274 	}
275 
276 	strlcpy(path2 + plen2, dp->d_name, MAXPATHLEN - plen2);
277 	if (stat(path2, &stb2) != 0) {
278 		if (!Nflag || errno != ENOENT) {
279 			warn("%s", path2);
280 			return;
281 		}
282 		flags |= D_EMPTY2;
283 		memset(&stb2, 0, sizeof(stb2));
284 		stb2.st_mode = stb1.st_mode;
285 	}
286 	if (stb1.st_mode == 0)
287 		stb1.st_mode = stb2.st_mode;
288 
289 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
290 		if (rflag)
291 			diffdir(path1, path2, flags);
292 		else if (lflag)
293 			dp->d_status |= D_COMMON;
294 		else
295 			printf("Common subdirectories: %s and %s\n",
296 			    path1, path2);
297 		return;
298 	}
299 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
300 		dp->d_status = D_SKIPPED1;
301 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
302 		dp->d_status = D_SKIPPED2;
303 	else
304 		dp->d_status = diffreg(path1, path2, flags);
305 	if (!lflag)
306 		print_status(dp->d_status, path1, path2, NULL);
307 }
308 
309 /*
310  * Exclude the given directory entry?
311  */
312 static int
313 excluded(const char *entry)
314 {
315 	struct excludes *excl;
316 
317 	/* always skip "." and ".." */
318 	if (entry[0] == '.' &&
319 	    (entry[1] == '\0' || (entry[1] == '.' && entry[2] == '\0')))
320 		return (1);
321 
322 	/* check excludes list */
323 	for (excl = excludes_list; excl != NULL; excl = excl->next)
324 		if (fnmatch(excl->pattern, entry, FNM_PATHNAME) == 0)
325 			return (1);
326 
327 	return (0);
328 }
329