1 /* Test of execution of file name canonicalization.
2 Copyright (C) 2007-2021 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Written by Bruno Haible <bruno@clisp.org>, 2007. */
18
19 /* Don't use __attribute__ __nonnull__ in this compilation unit. Otherwise gcc
20 may "optimize" the null_ptr function, when its result gets passed to a
21 function that has an argument declared as _GL_ARG_NONNULL. */
22 #define _GL_ARG_NONNULL(params)
23
24 #include <config.h>
25
26 #include <stdlib.h>
27
28 #include "signature.h"
29 SIGNATURE_CHECK (realpath, char *, (const char *, char *));
30 SIGNATURE_CHECK (canonicalize_file_name, char *, (const char *));
31
32 #include <errno.h>
33 #include <fcntl.h>
34 #include <stdio.h>
35 #include <string.h>
36 #include <sys/stat.h>
37 #include <unistd.h>
38
39 #include "same-inode.h"
40 #include "ignore-value.h"
41
42 #if GNULIB_defined_canonicalize_file_name
43 # include "null-ptr.h"
44 #endif
45
46 #include "macros.h"
47
48 #define BASE "t-can-lgpl.tmp"
49
50 int
51 main (void)
52 {
53 #if GNULIB_TEST_CANONICALIZE
54 /* No need to test canonicalize-lgpl module if canonicalize is also
55 in use. */
56 return 0;
57 #endif
58
59 /* Setup some hierarchy to be used by this test. Start by removing
60 any leftovers from a previous partial run. */
61 {
62 int fd;
63 ignore_value (system ("rm -rf " BASE " ise"));
64 ASSERT (mkdir (BASE, 0700) == 0);
65 fd = creat (BASE "/tra", 0600);
66 ASSERT (0 <= fd);
67 ASSERT (close (fd) == 0);
68 }
69
70 /* Check // handling (the easy cases, without symlinks).
71 This // handling is not mandated by POSIX. However, many applications
72 expect that canonicalize_file_name "canonicalizes" the file name,
73 that is, that different results of canonicalize_file_name correspond
74 to different files (except for hard links). */
75 {
76 char *result0 = canonicalize_file_name ("/etc/passwd");
77 if (result0 != NULL) /* This file does not exist on native Windows. */
78 {
79 char *result;
80
81 result = canonicalize_file_name ("/etc//passwd");
82 ASSERT (result != NULL && strcmp (result, result0) == 0);
83
84 result = canonicalize_file_name ("/etc///passwd");
85 ASSERT (result != NULL && strcmp (result, result0) == 0);
86
87 /* On Windows, the syntax //host/share/filename denotes a file
88 in a directory named 'share', exported from host 'host'.
89 See also m4/double-slash-root.m4. */
90 #if !(defined _WIN32 || defined __CYGWIN__)
91 result = canonicalize_file_name ("//etc/passwd");
92 ASSERT (result != NULL && strcmp (result, result0) == 0);
93
94 result = canonicalize_file_name ("//etc//passwd");
95 ASSERT (result != NULL && strcmp (result, result0) == 0);
96
97 result = canonicalize_file_name ("//etc///passwd");
98 ASSERT (result != NULL && strcmp (result, result0) == 0);
99 #endif
100
101 result = canonicalize_file_name ("///etc/passwd");
102 ASSERT (result != NULL && strcmp (result, result0) == 0);
103
104 result = canonicalize_file_name ("///etc//passwd");
105 ASSERT (result != NULL && strcmp (result, result0) == 0);
106
107 result = canonicalize_file_name ("///etc///passwd");
108 ASSERT (result != NULL && strcmp (result, result0) == 0);
109 }
110 }
111
112 /* Check for ., .., intermediate // handling, and for error cases. */
113 {
114 char *result = canonicalize_file_name (BASE "//./..//" BASE "/tra");
115 ASSERT (result != NULL);
116 ASSERT (strstr (result, "/" BASE "/tra")
117 == result + strlen (result) - strlen ("/" BASE "/tra"));
118 free (result);
119
120 errno = 0;
121 result = canonicalize_file_name ("");
122 ASSERT (result == NULL);
123 ASSERT (errno == ENOENT);
124
125 /* This test works only if the canonicalize_file_name implementation
126 comes from gnulib. If it comes from libc, we have no way to prevent
127 gcc from "optimizing" the null_ptr function in invalid ways. See
128 <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93156>. */
129 #if GNULIB_defined_canonicalize_file_name
130 errno = 0;
131 result = canonicalize_file_name (null_ptr ());
132 ASSERT (result == NULL);
133 ASSERT (errno == EINVAL);
134 #endif
135 }
136
137 /* Check that a non-directory with trailing slash yields NULL. */
138 {
139 char *result;
140 errno = 0;
141 result = canonicalize_file_name (BASE "/tra/");
142 ASSERT (result == NULL);
143 ASSERT (errno == ENOTDIR);
144 }
145
146 /* Check that a missing directory yields NULL. */
147 {
148 char *result;
149 errno = 0;
150 result = canonicalize_file_name (BASE "/zzz/..");
151 ASSERT (result == NULL);
152 ASSERT (errno == ENOENT);
153 }
154
155 /* From here on out, tests involve symlinks. */
156 if (symlink (BASE "/ket", "ise") != 0)
157 {
158 ASSERT (remove (BASE "/tra") == 0);
159 ASSERT (rmdir (BASE) == 0);
160 fputs ("skipping test: symlinks not supported on this file system\n",
161 stderr);
162 return 77;
163 }
164 ASSERT (symlink ("bef", BASE "/plo") == 0);
165 ASSERT (symlink ("tra", BASE "/huk") == 0);
166 ASSERT (symlink ("lum", BASE "/bef") == 0);
167 ASSERT (symlink ("wum", BASE "/ouk") == 0);
168 ASSERT (symlink ("../ise", BASE "/ket") == 0);
169 ASSERT (mkdir (BASE "/lum", 0700) == 0);
170 ASSERT (symlink ("//.//../..", BASE "/droot") == 0);
171
172 /* Check that the symbolic link to a file can be resolved. */
173 {
174 char *result1 = canonicalize_file_name (BASE "/huk");
175 char *result2 = canonicalize_file_name (BASE "/tra");
176 ASSERT (result1 != NULL);
177 ASSERT (result2 != NULL);
178 ASSERT (strcmp (result1, result2) == 0);
179 ASSERT (strcmp (result1 + strlen (result1) - strlen ("/" BASE "/tra"),
180 "/" BASE "/tra") == 0);
181 free (result1);
182 free (result2);
183 }
184
185 /* Check that the symbolic link to a directory can be resolved. */
186 {
187 char *result1 = canonicalize_file_name (BASE "/plo");
188 char *result2 = canonicalize_file_name (BASE "/bef");
189 char *result3 = canonicalize_file_name (BASE "/lum");
190 ASSERT (result1 != NULL);
191 ASSERT (result2 != NULL);
192 ASSERT (result3 != NULL);
193 ASSERT (strcmp (result1, result2) == 0);
194 ASSERT (strcmp (result2, result3) == 0);
195 ASSERT (strcmp (result1 + strlen (result1) - strlen ("/" BASE "/lum"),
196 "/" BASE "/lum") == 0);
197 free (result1);
198 free (result2);
199 free (result3);
200 }
201
202 /* Check that a symbolic link to a nonexistent file yields NULL. */
203 {
204 char *result;
205 errno = 0;
206 result = canonicalize_file_name (BASE "/ouk");
207 ASSERT (result == NULL);
208 ASSERT (errno == ENOENT);
209 }
210
211 /* Check that a non-directory symlink with trailing slash yields NULL,
212 and likewise for other troublesome suffixes. */
213 {
214 char const *const file_name[]
215 = {
216 BASE "/huk/",
217 BASE "/huk/.",
218 BASE "/huk/./",
219 BASE "/huk/./.",
220 BASE "/huk/x",
221 BASE "/huk/..",
222 BASE "/huk/../",
223 BASE "/huk/../.",
224 BASE "/huk/../x",
225 BASE "/huk/./..",
226 BASE "/huk/././../x",
227 };
228 for (int i = 0; i < sizeof file_name / sizeof *file_name; i++)
229 {
230 errno = 0;
231 ASSERT (!canonicalize_file_name (file_name[i]));
232 ASSERT (errno == ENOTDIR);
233 }
234 }
235
236 /* Check that a missing directory via symlink yields NULL. */
237 {
238 char *result;
239 errno = 0;
240 result = canonicalize_file_name (BASE "/ouk/..");
241 ASSERT (result == NULL);
242 ASSERT (errno == ENOENT);
243 }
244
245 /* Check that a loop of symbolic links is detected. */
246 {
247 char *result;
248 errno = 0;
249 result = canonicalize_file_name ("ise");
250 ASSERT (result == NULL);
251 ASSERT (errno == ELOOP);
252 }
253
254 /* Check that leading // within symlinks is honored correctly. */
255 {
256 struct stat st1;
257 struct stat st2;
258 char *result1 = canonicalize_file_name ("//.");
259 char *result2 = canonicalize_file_name (BASE "/droot");
260 ASSERT (result1);
261 ASSERT (result2);
262 ASSERT (stat ("/", &st1) == 0);
263 ASSERT (stat ("//", &st2) == 0);
264 /* On IBM z/OS, "/" and "//" are distinct, yet they both have
265 st_dev == st_ino == 1. */
266 #ifndef __MVS__
267 if (SAME_INODE (st1, st2))
268 {
269 ASSERT (strcmp (result1, "/") == 0);
270 ASSERT (strcmp (result2, "/") == 0);
271 }
272 else
273 #endif
274 {
275 ASSERT (strcmp (result1, "//") == 0);
276 ASSERT (strcmp (result2, "//") == 0);
277 }
278 free (result1);
279 free (result2);
280 }
281
282
283 /* Cleanup. */
284 ASSERT (remove (BASE "/droot") == 0);
285 ASSERT (remove (BASE "/plo") == 0);
286 ASSERT (remove (BASE "/huk") == 0);
287 ASSERT (remove (BASE "/bef") == 0);
288 ASSERT (remove (BASE "/ouk") == 0);
289 ASSERT (remove (BASE "/ket") == 0);
290 ASSERT (remove (BASE "/lum") == 0);
291 ASSERT (remove (BASE "/tra") == 0);
292 ASSERT (remove (BASE) == 0);
293 ASSERT (remove ("ise") == 0);
294
295 return 0;
296 }