xref: /openbsd/usr.bin/diff/diffdir.c (revision 8529ddd3)
1 /*	$OpenBSD: diffdir.c,v 1.43 2015/01/16 06:40:07 deraadt 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/stat.h>
24 
25 #include <dirent.h>
26 #include <err.h>
27 #include <errno.h>
28 #include <fcntl.h>
29 #include <fnmatch.h>
30 #include <paths.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <unistd.h>
35 #include <limits.h>
36 
37 #include "diff.h"
38 #include "xmalloc.h"
39 
40 static int selectfile(const struct dirent *);
41 static void diffit(struct dirent *, char *, size_t, char *, size_t, int);
42 
43 #define d_status	d_type		/* we need to store status for -l */
44 
45 /*
46  * Diff directory traversal. Will be called recursively if -r was specified.
47  */
48 void
49 diffdir(char *p1, char *p2, int flags)
50 {
51 	struct dirent *dent1, **dp1, **edp1, **dirp1 = NULL;
52 	struct dirent *dent2, **dp2, **edp2, **dirp2 = NULL;
53 	size_t dirlen1, dirlen2;
54 	char path1[PATH_MAX], path2[PATH_MAX];
55 	int pos;
56 
57 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
58 	if (dirlen1 >= sizeof(path1) - 1) {
59 		warnc(ENAMETOOLONG, "%s", p1);
60 		status = 2;
61 		return;
62 	}
63 	if (path1[dirlen1 - 1] != '/') {
64 		path1[dirlen1++] = '/';
65 		path1[dirlen1] = '\0';
66 	}
67 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
68 	if (dirlen2 >= sizeof(path2) - 1) {
69 		warnc(ENAMETOOLONG, "%s", p2);
70 		status = 2;
71 		return;
72 	}
73 	if (path2[dirlen2 - 1] != '/') {
74 		path2[dirlen2++] = '/';
75 		path2[dirlen2] = '\0';
76 	}
77 
78 	/*
79 	 * Get a list of entries in each directory, skipping "excluded" files
80 	 * and sorting alphabetically.
81 	 */
82 	pos = scandir(path1, &dirp1, selectfile, alphasort);
83 	if (pos == -1) {
84 		if (errno == ENOENT && (Nflag || Pflag)) {
85 			pos = 0;
86 		} else {
87 			warn("%s", path1);
88 			goto closem;
89 		}
90 	}
91 	dp1 = dirp1;
92 	edp1 = dirp1 + pos;
93 
94 	pos = scandir(path2, &dirp2, selectfile, alphasort);
95 	if (pos == -1) {
96 		if (errno == ENOENT && Nflag) {
97 			pos = 0;
98 		} else {
99 			warn("%s", path2);
100 			goto closem;
101 		}
102 	}
103 	dp2 = dirp2;
104 	edp2 = dirp2 + pos;
105 
106 	/*
107 	 * If we were given a starting point, find it.
108 	 */
109 	if (start != NULL) {
110 		while (dp1 != edp1 && strcmp((*dp1)->d_name, start) < 0)
111 			dp1++;
112 		while (dp2 != edp2 && strcmp((*dp2)->d_name, start) < 0)
113 			dp2++;
114 	}
115 
116 	/*
117 	 * Iterate through the two directory lists, diffing as we go.
118 	 */
119 	while (dp1 != edp1 || dp2 != edp2) {
120 		dent1 = dp1 != edp1 ? *dp1 : NULL;
121 		dent2 = dp2 != edp2 ? *dp2 : NULL;
122 
123 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
124 		    strcmp(dent1->d_name, dent2->d_name);
125 		if (pos == 0) {
126 			/* file exists in both dirs, diff it */
127 			diffit(dent1, path1, dirlen1, path2, dirlen2, flags);
128 			dp1++;
129 			dp2++;
130 		} else if (pos < 0) {
131 			/* file only in first dir, only diff if -N */
132 			if (Nflag)
133 				diffit(dent1, path1, dirlen1, path2, dirlen2,
134 				    flags);
135 			else if (lflag)
136 				dent1->d_status |= D_ONLY;
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 if (lflag)
146 				dent2->d_status |= D_ONLY;
147 			else
148 				print_only(path2, dirlen2, dent2->d_name);
149 			dp2++;
150 		}
151 	}
152 	if (lflag) {
153 		path1[dirlen1] = '\0';
154 		path2[dirlen2] = '\0';
155 		for (dp1 = dirp1; (dent1 = *dp1) != NULL; dp1++) {
156 			print_status(dent1->d_status, path1, path2,
157 			    dent1->d_name);
158 		}
159 		for (dp2 = dirp2; (dent2 = *dp2) != NULL; dp2++) {
160 			if (dent2->d_status == D_ONLY)
161 				print_status(dent2->d_status, path2, NULL,
162 				    dent2->d_name);
163 		}
164 	}
165 
166 closem:
167 	if (dirp1 != NULL) {
168 		for (dp1 = dirp1; dp1 < edp1; dp1++)
169 			xfree(*dp1);
170 		xfree(dirp1);
171 	}
172 	if (dirp2 != NULL) {
173 		for (dp2 = dirp2; dp2 < edp2; dp2++)
174 			xfree(*dp2);
175 		xfree(dirp2);
176 	}
177 }
178 
179 /*
180  * Do the actual diff by calling either diffreg() or diffdir().
181  */
182 static void
183 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
184     int flags)
185 {
186 	flags |= D_HEADER;
187 	strlcpy(path1 + plen1, dp->d_name, PATH_MAX - plen1);
188 	if (stat(path1, &stb1) != 0) {
189 		if (!(Nflag || Pflag) || errno != ENOENT) {
190 			warn("%s", path1);
191 			return;
192 		}
193 		flags |= D_EMPTY1;
194 		memset(&stb1, 0, sizeof(stb1));
195 	}
196 
197 	strlcpy(path2 + plen2, dp->d_name, PATH_MAX - plen2);
198 	if (stat(path2, &stb2) != 0) {
199 		if (!Nflag || errno != ENOENT) {
200 			warn("%s", path2);
201 			return;
202 		}
203 		flags |= D_EMPTY2;
204 		memset(&stb2, 0, sizeof(stb2));
205 		stb2.st_mode = stb1.st_mode;
206 	}
207 	if (stb1.st_mode == 0)
208 		stb1.st_mode = stb2.st_mode;
209 
210 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
211 		if (rflag)
212 			diffdir(path1, path2, flags);
213 		else if (lflag)
214 			dp->d_status |= D_COMMON;
215 		else
216 			printf("Common subdirectories: %s and %s\n",
217 			    path1, path2);
218 		return;
219 	}
220 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
221 		dp->d_status = D_SKIPPED1;
222 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
223 		dp->d_status = D_SKIPPED2;
224 	else
225 		dp->d_status = diffreg(path1, path2, flags);
226 	if (!lflag)
227 		print_status(dp->d_status, path1, path2, "");
228 }
229 
230 /*
231  * Returns 1 if the directory entry should be included in the
232  * diff, else 0.  Checks the excludes list.
233  */
234 static int
235 selectfile(const struct dirent *dp)
236 {
237 	struct excludes *excl;
238 
239 	if (dp->d_fileno == 0)
240 		return (0);
241 
242 	/* always skip "." and ".." */
243 	if (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' ||
244 	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
245 		return (0);
246 
247 	/* check excludes list */
248 	for (excl = excludes_list; excl != NULL; excl = excl->next)
249 		if (fnmatch(excl->pattern, dp->d_name, FNM_PATHNAME) == 0)
250 			return (0);
251 
252 	return (1);
253 }
254