xref: /freebsd/usr.bin/diff/diffdir.c (revision 74c9a5910cdd44f15bdad639141ebb2b007a027d)
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/cdefs.h>
24 __FBSDID("$FreeBSD$");
25 
26 #include <sys/stat.h>
27 
28 #include <dirent.h>
29 #include <err.h>
30 #include <errno.h>
31 #include <fnmatch.h>
32 #include <stdio.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <limits.h>
36 
37 #include "diff.h"
38 
39 static int selectfile(const struct dirent *);
40 static void diffit(struct dirent *, char *, size_t, char *, size_t, int);
41 
42 #define d_status	d_type		/* we need to store status for -l */
43 
44 /*
45  * Diff directory traversal. Will be called recursively if -r was specified.
46  */
47 void
48 diffdir(char *p1, char *p2, int flags)
49 {
50 	struct dirent *dent1, **dp1, **edp1, **dirp1 = NULL;
51 	struct dirent *dent2, **dp2, **edp2, **dirp2 = NULL;
52 	size_t dirlen1, dirlen2;
53 	char path1[PATH_MAX], path2[PATH_MAX];
54 	int pos;
55 
56 	edp1 = edp2 = NULL;
57 
58 	dirlen1 = strlcpy(path1, *p1 ? p1 : ".", sizeof(path1));
59 	if (dirlen1 >= sizeof(path1) - 1) {
60 		warnc(ENAMETOOLONG, "%s", p1);
61 		status = 2;
62 		return;
63 	}
64 	if (path1[dirlen1 - 1] != '/') {
65 		path1[dirlen1++] = '/';
66 		path1[dirlen1] = '\0';
67 	}
68 	dirlen2 = strlcpy(path2, *p2 ? p2 : ".", sizeof(path2));
69 	if (dirlen2 >= sizeof(path2) - 1) {
70 		warnc(ENAMETOOLONG, "%s", p2);
71 		status = 2;
72 		return;
73 	}
74 	if (path2[dirlen2 - 1] != '/') {
75 		path2[dirlen2++] = '/';
76 		path2[dirlen2] = '\0';
77 	}
78 
79 	/*
80 	 * Get a list of entries in each directory, skipping "excluded" files
81 	 * and sorting alphabetically.
82 	 */
83 	pos = scandir(path1, &dirp1, selectfile, alphasort);
84 	if (pos == -1) {
85 		if (errno == ENOENT && (Nflag || Pflag)) {
86 			pos = 0;
87 		} else {
88 			warn("%s", path1);
89 			goto closem;
90 		}
91 	}
92 	dp1 = dirp1;
93 	edp1 = dirp1 + pos;
94 
95 	pos = scandir(path2, &dirp2, selectfile, alphasort);
96 	if (pos == -1) {
97 		if (errno == ENOENT && Nflag) {
98 			pos = 0;
99 		} else {
100 			warn("%s", path2);
101 			goto closem;
102 		}
103 	}
104 	dp2 = dirp2;
105 	edp2 = dirp2 + pos;
106 
107 	/*
108 	 * If we were given a starting point, find it.
109 	 */
110 	if (start != NULL) {
111 		while (dp1 != edp1 && strcmp((*dp1)->d_name, start) < 0)
112 			dp1++;
113 		while (dp2 != edp2 && strcmp((*dp2)->d_name, start) < 0)
114 			dp2++;
115 	}
116 
117 	/*
118 	 * Iterate through the two directory lists, diffing as we go.
119 	 */
120 	while (dp1 != edp1 || dp2 != edp2) {
121 		dent1 = dp1 != edp1 ? *dp1 : NULL;
122 		dent2 = dp2 != edp2 ? *dp2 : NULL;
123 
124 		pos = dent1 == NULL ? 1 : dent2 == NULL ? -1 :
125 		    ignore_file_case ? strcasecmp(dent1->d_name, dent2->d_name) :
126 		    strcmp(dent1->d_name, dent2->d_name) ;
127 		if (pos == 0) {
128 			/* file exists in both dirs, diff it */
129 			diffit(dent1, path1, dirlen1, path2, dirlen2, flags);
130 			dp1++;
131 			dp2++;
132 		} else if (pos < 0) {
133 			/* file only in first dir, only diff if -N */
134 			if (Nflag)
135 				diffit(dent1, path1, dirlen1, path2, dirlen2,
136 				    flags);
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
146 				print_only(path2, dirlen2, dent2->d_name);
147 			dp2++;
148 		}
149 	}
150 
151 closem:
152 	if (dirp1 != NULL) {
153 		for (dp1 = dirp1; dp1 < edp1; dp1++)
154 			free(*dp1);
155 		free(dirp1);
156 	}
157 	if (dirp2 != NULL) {
158 		for (dp2 = dirp2; dp2 < edp2; dp2++)
159 			free(*dp2);
160 		free(dirp2);
161 	}
162 }
163 
164 /*
165  * Do the actual diff by calling either diffreg() or diffdir().
166  */
167 static void
168 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
169     int flags)
170 {
171 	flags |= D_HEADER;
172 	strlcpy(path1 + plen1, dp->d_name, PATH_MAX - plen1);
173 	if (stat(path1, &stb1) != 0) {
174 		if (!(Nflag || Pflag) || errno != ENOENT) {
175 			warn("%s", path1);
176 			return;
177 		}
178 		flags |= D_EMPTY1;
179 		memset(&stb1, 0, sizeof(stb1));
180 	}
181 
182 	strlcpy(path2 + plen2, dp->d_name, PATH_MAX - plen2);
183 	if (stat(path2, &stb2) != 0) {
184 		if (!Nflag || errno != ENOENT) {
185 			warn("%s", path2);
186 			return;
187 		}
188 		flags |= D_EMPTY2;
189 		memset(&stb2, 0, sizeof(stb2));
190 		stb2.st_mode = stb1.st_mode;
191 	}
192 	if (stb1.st_mode == 0)
193 		stb1.st_mode = stb2.st_mode;
194 
195 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
196 		if (rflag)
197 			diffdir(path1, path2, flags);
198 		else
199 			printf("Common subdirectories: %s and %s\n",
200 			    path1, path2);
201 		return;
202 	}
203 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
204 		dp->d_status = D_SKIPPED1;
205 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
206 		dp->d_status = D_SKIPPED2;
207 	else
208 		dp->d_status = diffreg(path1, path2, flags, 0);
209 	print_status(dp->d_status, path1, path2, "");
210 }
211 
212 /*
213  * Returns 1 if the directory entry should be included in the
214  * diff, else 0.  Checks the excludes list.
215  */
216 static int
217 selectfile(const struct dirent *dp)
218 {
219 	struct excludes *excl;
220 
221 	if (dp->d_fileno == 0)
222 		return (0);
223 
224 	/* always skip "." and ".." */
225 	if (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' ||
226 	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
227 		return (0);
228 
229 	/* check excludes list */
230 	for (excl = excludes_list; excl != NULL; excl = excl->next)
231 		if (fnmatch(excl->pattern, dp->d_name, FNM_PATHNAME) == 0)
232 			return (0);
233 
234 	return (1);
235 }
236