xref: /openbsd/usr.bin/diff/diffdir.c (revision bf198cc6)
1 /*	$OpenBSD: diffdir.c,v 1.47 2019/01/25 00:19:26 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 2003, 2010 Todd C. Miller <millert@openbsd.org>
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
diffdir(char * p1,char * p2,int flags)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 				status |= 1;
138 			}
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 				status |= 1;
148 			}
149 			dp2++;
150 		}
151 	}
152 
153 closem:
154 	if (dirp1 != NULL) {
155 		for (dp1 = dirp1; dp1 < edp1; dp1++)
156 			free(*dp1);
157 		free(dirp1);
158 	}
159 	if (dirp2 != NULL) {
160 		for (dp2 = dirp2; dp2 < edp2; dp2++)
161 			free(*dp2);
162 		free(dirp2);
163 	}
164 }
165 
166 /*
167  * Do the actual diff by calling either diffreg() or diffdir().
168  */
169 static void
diffit(struct dirent * dp,char * path1,size_t plen1,char * path2,size_t plen2,int flags)170 diffit(struct dirent *dp, char *path1, size_t plen1, char *path2, size_t plen2,
171     int flags)
172 {
173 	flags |= D_HEADER;
174 	strlcpy(path1 + plen1, dp->d_name, PATH_MAX - plen1);
175 	if (stat(path1, &stb1) != 0) {
176 		if (!(Nflag || Pflag) || errno != ENOENT) {
177 			warn("%s", path1);
178 			return;
179 		}
180 		flags |= D_EMPTY1;
181 		memset(&stb1, 0, sizeof(stb1));
182 	}
183 
184 	strlcpy(path2 + plen2, dp->d_name, PATH_MAX - plen2);
185 	if (stat(path2, &stb2) != 0) {
186 		if (!Nflag || errno != ENOENT) {
187 			warn("%s", path2);
188 			return;
189 		}
190 		flags |= D_EMPTY2;
191 		memset(&stb2, 0, sizeof(stb2));
192 		stb2.st_mode = stb1.st_mode;
193 	}
194 	if (stb1.st_mode == 0)
195 		stb1.st_mode = stb2.st_mode;
196 
197 	if (S_ISDIR(stb1.st_mode) && S_ISDIR(stb2.st_mode)) {
198 		if (rflag)
199 			diffdir(path1, path2, flags);
200 		else
201 			printf("Common subdirectories: %s and %s\n",
202 			    path1, path2);
203 		return;
204 	}
205 	if (!S_ISREG(stb1.st_mode) && !S_ISDIR(stb1.st_mode))
206 		dp->d_status = D_SKIPPED1;
207 	else if (!S_ISREG(stb2.st_mode) && !S_ISDIR(stb2.st_mode))
208 		dp->d_status = D_SKIPPED2;
209 	else
210 		dp->d_status = diffreg(path1, path2, flags);
211 	print_status(dp->d_status, path1, path2, "");
212 }
213 
214 /*
215  * Returns 1 if the directory entry should be included in the
216  * diff, else 0.  Checks the excludes list.
217  */
218 static int
selectfile(const struct dirent * dp)219 selectfile(const struct dirent *dp)
220 {
221 	struct excludes *excl;
222 
223 	if (dp->d_fileno == 0)
224 		return (0);
225 
226 	/* always skip "." and ".." */
227 	if (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' ||
228 	    (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
229 		return (0);
230 
231 	/* check excludes list */
232 	for (excl = excludes_list; excl != NULL; excl = excl->next)
233 		if (fnmatch(excl->pattern, dp->d_name, FNM_PATHNAME) == 0)
234 			return (0);
235 
236 	return (1);
237 }
238