xref: /openbsd/usr.bin/diff/diffdir.c (revision 5af055cd)
1 /*	$OpenBSD: diffdir.c,v 1.45 2015/10/05 20:15:00 millert 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
136 				print_only(path1, dirlen1, dent1->d_name);
137 			dp1++;
138 		} else {
139 			/* file only in second dir, only diff if -N or -P */
140 			if (Nflag || Pflag)
141 				diffit(dent2, path1, dirlen1, path2, dirlen2,
142 				    flags);
143 			else
144 				print_only(path2, dirlen2, dent2->d_name);
145 			dp2++;
146 		}
147 	}
148 
149 closem:
150 	if (dirp1 != NULL) {
151 		for (dp1 = dirp1; dp1 < edp1; dp1++)
152 			free(*dp1);
153 		free(dirp1);
154 	}
155 	if (dirp2 != NULL) {
156 		for (dp2 = dirp2; dp2 < edp2; dp2++)
157 			free(*dp2);
158 		free(dirp2);
159 	}
160 }
161 
162 /*
163  * Do the actual diff by calling either diffreg() or diffdir().
164  */
165 static void
166 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
167     int flags)
168 {
169 	flags |= D_HEADER;
170 	strlcpy(path1 + plen1, dp->d_name, PATH_MAX - plen1);
171 	if (stat(path1, &stb1) != 0) {
172 		if (!(Nflag || Pflag) || errno != ENOENT) {
173 			warn("%s", path1);
174 			return;
175 		}
176 		flags |= D_EMPTY1;
177 		memset(&stb1, 0, sizeof(stb1));
178 	}
179 
180 	strlcpy(path2 + plen2, dp->d_name, PATH_MAX - plen2);
181 	if (stat(path2, &stb2) != 0) {
182 		if (!Nflag || errno != ENOENT) {
183 			warn("%s", path2);
184 			return;
185 		}
186 		flags |= D_EMPTY2;
187 		memset(&stb2, 0, sizeof(stb2));
188 		stb2.st_mode = stb1.st_mode;
189 	}
190 	if (stb1.st_mode == 0)
191 		stb1.st_mode = stb2.st_mode;
192 
193 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
194 		if (rflag)
195 			diffdir(path1, path2, flags);
196 		else
197 			printf("Common subdirectories: %s and %s\n",
198 			    path1, path2);
199 		return;
200 	}
201 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
202 		dp->d_status = D_SKIPPED1;
203 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
204 		dp->d_status = D_SKIPPED2;
205 	else
206 		dp->d_status = diffreg(path1, path2, flags);
207 	print_status(dp->d_status, path1, path2, "");
208 }
209 
210 /*
211  * Returns 1 if the directory entry should be included in the
212  * diff, else 0.  Checks the excludes list.
213  */
214 static int
215 selectfile(const struct dirent *dp)
216 {
217 	struct excludes *excl;
218 
219 	if (dp->d_fileno == 0)
220 		return (0);
221 
222 	/* always skip "." and ".." */
223 	if (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' ||
224 	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
225 		return (0);
226 
227 	/* check excludes list */
228 	for (excl = excludes_list; excl != NULL; excl = excl->next)
229 		if (fnmatch(excl->pattern, dp->d_name, FNM_PATHNAME) == 0)
230 			return (0);
231 
232 	return (1);
233 }
234