1 /* Test of fcntl(2).
2 Copyright (C) 2009-2012 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 <http://www.gnu.org/licenses/>. */
16
17 /* Written by Eric Blake <ebb9@byu.net>, 2009. */
18
19 #include <config.h>
20
21 /* Specification. */
22 #include <fcntl.h>
23
24 #include "signature.h"
25 SIGNATURE_CHECK (fcntl, int, (int, int, ...));
26
27 /* Helpers. */
28 #include <errno.h>
29 #include <stdarg.h>
30 #include <stdbool.h>
31 #include <unistd.h>
32
33 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
34 /* Get declarations of the native Windows API functions. */
35 # define WIN32_LEAN_AND_MEAN
36 # include <windows.h>
37 /* Get _get_osfhandle. */
38 # include "msvc-nothrow.h"
39 #endif
40
41 #include "binary-io.h"
42 #include "macros.h"
43
44 #if !O_BINARY
45 # define setmode(f,m) zero ()
zero(void)46 static int zero (void) { return 0; }
47 #endif
48
49 /* Return true if FD is open. */
50 static bool
is_open(int fd)51 is_open (int fd)
52 {
53 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
54 /* On native Windows, the initial state of unassigned standard file
55 descriptors is that they are open but point to an
56 INVALID_HANDLE_VALUE, and there is no fcntl. */
57 return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
58 #else
59 # ifndef F_GETFL
60 # error Please port fcntl to your platform
61 # endif
62 return 0 <= fcntl (fd, F_GETFL);
63 #endif
64 }
65
66 /* Return true if FD is open and inheritable across exec/spawn. */
67 static bool
is_inheritable(int fd)68 is_inheritable (int fd)
69 {
70 #if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
71 /* On native Windows, the initial state of unassigned standard file
72 descriptors is that they are open but point to an
73 INVALID_HANDLE_VALUE, and there is no fcntl. */
74 HANDLE h = (HANDLE) _get_osfhandle (fd);
75 DWORD flags;
76 if (h == INVALID_HANDLE_VALUE || GetHandleInformation (h, &flags) == 0)
77 return false;
78 return (flags & HANDLE_FLAG_INHERIT) != 0;
79 #else
80 # ifndef F_GETFD
81 # error Please port fcntl to your platform
82 # endif
83 int i = fcntl (fd, F_GETFD);
84 return 0 <= i && (i & FD_CLOEXEC) == 0;
85 #endif
86 }
87
88 /* Return non-zero if FD is open in the given MODE, which is either
89 O_TEXT or O_BINARY. */
90 static bool
is_mode(int fd,int mode)91 is_mode (int fd, int mode)
92 {
93 int value = setmode (fd, O_BINARY);
94 setmode (fd, value);
95 return mode == value;
96 }
97
98 /* Since native fcntl can have more supported operations than our
99 replacement is aware of, and since various operations assign
100 different types to the vararg argument, a wrapper around fcntl must
101 be able to pass a vararg of unknown type on through to the original
102 fcntl. Make sure that this works properly: func1 behaves like the
103 original fcntl interpreting the vararg as an int or a pointer to a
104 struct, and func2 behaves like rpl_fcntl that doesn't know what
105 type to forward. */
106 struct dummy_struct
107 {
108 long filler;
109 int value;
110 };
111 static int
func1(int a,...)112 func1 (int a, ...)
113 {
114 va_list arg;
115 int i;
116 va_start (arg, a);
117 if (a < 4)
118 i = va_arg (arg, int);
119 else
120 {
121 struct dummy_struct *s = va_arg (arg, struct dummy_struct *);
122 i = s->value;
123 }
124 va_end (arg);
125 return i;
126 }
127 static int
func2(int a,...)128 func2 (int a, ...)
129 {
130 va_list arg;
131 void *p;
132 va_start (arg, a);
133 p = va_arg (arg, void *);
134 va_end (arg);
135 return func1 (a, p);
136 }
137
138 /* Ensure that all supported fcntl actions are distinct, and
139 usable in preprocessor expressions. */
140 static void
check_flags(void)141 check_flags (void)
142 {
143 switch (0)
144 {
145 case F_DUPFD:
146 #if F_DUPFD
147 #endif
148
149 case F_DUPFD_CLOEXEC:
150 #if F_DUPFD_CLOEXEC
151 #endif
152
153 case F_GETFD:
154 #if F_GETFD
155 #endif
156
157 #ifdef F_SETFD
158 case F_SETFD:
159 # if F_SETFD
160 # endif
161 #endif
162
163 #ifdef F_GETFL
164 case F_GETFL:
165 # if F_GETFL
166 # endif
167 #endif
168
169 #ifdef F_SETFL
170 case F_SETFL:
171 # if F_SETFL
172 # endif
173 #endif
174
175 #ifdef F_GETOWN
176 case F_GETOWN:
177 # if F_GETOWN
178 # endif
179 #endif
180
181 #ifdef F_SETOWN
182 case F_SETOWN:
183 # if F_SETOWN
184 # endif
185 #endif
186
187 #ifdef F_GETLK
188 case F_GETLK:
189 # if F_GETLK
190 # endif
191 #endif
192
193 #ifdef F_SETLK
194 case F_SETLK:
195 # if F_SETLK
196 # endif
197 #endif
198
199 #ifdef F_SETLKW
200 case F_SETLKW:
201 # if F_SETLKW
202 # endif
203 #endif
204
205 ;
206 }
207 }
208
209 int
main(void)210 main (void)
211 {
212 const char *file = "test-fcntl.tmp";
213 int fd;
214
215 /* Sanity check that rpl_fcntl is likely to work. */
216 ASSERT (func2 (1, 2) == 2);
217 ASSERT (func2 (2, -2) == -2);
218 ASSERT (func2 (3, 0x80000000) == 0x80000000);
219 {
220 struct dummy_struct s = { 0L, 4 };
221 ASSERT (func2 (4, &s) == 4);
222 }
223 check_flags ();
224
225 /* Assume std descriptors were provided by invoker, and ignore fds
226 that might have been inherited. */
227 fd = creat (file, 0600);
228 ASSERT (STDERR_FILENO < fd);
229 close (fd + 1);
230 close (fd + 2);
231
232 /* For F_DUPFD*, the source must be valid. */
233 errno = 0;
234 ASSERT (fcntl (-1, F_DUPFD, 0) == -1);
235 ASSERT (errno == EBADF);
236 errno = 0;
237 ASSERT (fcntl (fd + 1, F_DUPFD, 0) == -1);
238 ASSERT (errno == EBADF);
239 errno = 0;
240 ASSERT (fcntl (10000000, F_DUPFD, 0) == -1);
241 ASSERT (errno == EBADF);
242 errno = 0;
243 ASSERT (fcntl (-1, F_DUPFD_CLOEXEC, 0) == -1);
244 ASSERT (errno == EBADF);
245 errno = 0;
246 ASSERT (fcntl (fd + 1, F_DUPFD_CLOEXEC, 0) == -1);
247 ASSERT (errno == EBADF);
248 errno = 0;
249 ASSERT (fcntl (10000000, F_DUPFD_CLOEXEC, 0) == -1);
250 ASSERT (errno == EBADF);
251
252 /* For F_DUPFD*, the destination must be valid. */
253 ASSERT (getdtablesize () < 10000000);
254 errno = 0;
255 ASSERT (fcntl (fd, F_DUPFD, -1) == -1);
256 ASSERT (errno == EINVAL);
257 errno = 0;
258 ASSERT (fcntl (fd, F_DUPFD, 10000000) == -1);
259 ASSERT (errno == EINVAL);
260 ASSERT (getdtablesize () < 10000000);
261 errno = 0;
262 ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, -1) == -1);
263 ASSERT (errno == EINVAL);
264 errno = 0;
265 ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, 10000000) == -1);
266 ASSERT (errno == EINVAL);
267
268 /* For F_DUPFD*, check for correct inheritance, as well as
269 preservation of text vs. binary. */
270 setmode (fd, O_BINARY);
271 ASSERT (is_open (fd));
272 ASSERT (!is_open (fd + 1));
273 ASSERT (!is_open (fd + 2));
274 ASSERT (is_inheritable (fd));
275 ASSERT (is_mode (fd, O_BINARY));
276
277 ASSERT (fcntl (fd, F_DUPFD, fd) == fd + 1);
278 ASSERT (is_open (fd));
279 ASSERT (is_open (fd + 1));
280 ASSERT (!is_open (fd + 2));
281 ASSERT (is_inheritable (fd + 1));
282 ASSERT (is_mode (fd, O_BINARY));
283 ASSERT (is_mode (fd + 1, O_BINARY));
284 ASSERT (close (fd + 1) == 0);
285
286 ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, fd + 2) == fd + 2);
287 ASSERT (is_open (fd));
288 ASSERT (!is_open (fd + 1));
289 ASSERT (is_open (fd + 2));
290 ASSERT (is_inheritable (fd));
291 ASSERT (!is_inheritable (fd + 2));
292 ASSERT (is_mode (fd, O_BINARY));
293 ASSERT (is_mode (fd + 2, O_BINARY));
294 ASSERT (close (fd) == 0);
295
296 setmode (fd + 2, O_TEXT);
297 ASSERT (fcntl (fd + 2, F_DUPFD, fd + 1) == fd + 1);
298 ASSERT (!is_open (fd));
299 ASSERT (is_open (fd + 1));
300 ASSERT (is_open (fd + 2));
301 ASSERT (is_inheritable (fd + 1));
302 ASSERT (!is_inheritable (fd + 2));
303 ASSERT (is_mode (fd + 1, O_TEXT));
304 ASSERT (is_mode (fd + 2, O_TEXT));
305 ASSERT (close (fd + 1) == 0);
306
307 ASSERT (fcntl (fd + 2, F_DUPFD_CLOEXEC, 0) == fd);
308 ASSERT (is_open (fd));
309 ASSERT (!is_open (fd + 1));
310 ASSERT (is_open (fd + 2));
311 ASSERT (!is_inheritable (fd));
312 ASSERT (!is_inheritable (fd + 2));
313 ASSERT (is_mode (fd, O_TEXT));
314 ASSERT (is_mode (fd + 2, O_TEXT));
315 ASSERT (close (fd + 2) == 0);
316
317 /* Test F_GETFD on invalid file descriptors. */
318 errno = 0;
319 ASSERT (fcntl (-1, F_GETFD) == -1);
320 ASSERT (errno == EBADF);
321 errno = 0;
322 ASSERT (fcntl (fd + 1, F_GETFD) == -1);
323 ASSERT (errno == EBADF);
324 errno = 0;
325 ASSERT (fcntl (10000000, F_GETFD) == -1);
326 ASSERT (errno == EBADF);
327
328 /* Test F_GETFD, the FD_CLOEXEC bit. */
329 {
330 int result = fcntl (fd, F_GETFD);
331 ASSERT (0 <= result);
332 ASSERT ((result & FD_CLOEXEC) == FD_CLOEXEC);
333 ASSERT (dup (fd) == fd + 1);
334 result = fcntl (fd + 1, F_GETFD);
335 ASSERT (0 <= result);
336 ASSERT ((result & FD_CLOEXEC) == 0);
337 ASSERT (close (fd + 1) == 0);
338 }
339
340 #ifdef F_SETFD
341 /* Test F_SETFD on invalid file descriptors. */
342 errno = 0;
343 ASSERT (fcntl (-1, F_SETFD, 0) == -1);
344 ASSERT (errno == EBADF);
345 errno = 0;
346 ASSERT (fcntl (fd + 1, F_SETFD, 0) == -1);
347 ASSERT (errno == EBADF);
348 errno = 0;
349 ASSERT (fcntl (10000000, F_SETFD, 0) == -1);
350 ASSERT (errno == EBADF);
351 #endif
352
353 #ifdef F_GETFL
354 /* Test F_GETFL on invalid file descriptors. */
355 errno = 0;
356 ASSERT (fcntl (-1, F_GETFL) == -1);
357 ASSERT (errno == EBADF);
358 errno = 0;
359 ASSERT (fcntl (fd + 1, F_GETFL) == -1);
360 ASSERT (errno == EBADF);
361 errno = 0;
362 ASSERT (fcntl (10000000, F_GETFL) == -1);
363 ASSERT (errno == EBADF);
364 #endif
365
366 #ifdef F_SETFL
367 /* Test F_SETFL on invalid file descriptors. */
368 errno = 0;
369 ASSERT (fcntl (-1, F_SETFL, 0) == -1);
370 ASSERT (errno == EBADF);
371 errno = 0;
372 ASSERT (fcntl (fd + 1, F_SETFL, 0) == -1);
373 ASSERT (errno == EBADF);
374 errno = 0;
375 ASSERT (fcntl (10000000, F_SETFL, 0) == -1);
376 ASSERT (errno == EBADF);
377 #endif
378
379 #ifdef F_GETOWN
380 /* Test F_GETOWN on invalid file descriptors. */
381 errno = 0;
382 ASSERT (fcntl (-1, F_GETOWN) == -1);
383 ASSERT (errno == EBADF);
384 errno = 0;
385 ASSERT (fcntl (fd + 1, F_GETOWN) == -1);
386 ASSERT (errno == EBADF);
387 errno = 0;
388 ASSERT (fcntl (10000000, F_GETOWN) == -1);
389 ASSERT (errno == EBADF);
390 #endif
391
392 #ifdef F_SETOWN
393 /* Test F_SETFL on invalid file descriptors. */
394 errno = 0;
395 ASSERT (fcntl (-1, F_SETOWN, 0) == -1);
396 ASSERT (errno == EBADF);
397 errno = 0;
398 ASSERT (fcntl (fd + 1, F_SETOWN, 0) == -1);
399 ASSERT (errno == EBADF);
400 errno = 0;
401 ASSERT (fcntl (10000000, F_SETOWN, 0) == -1);
402 ASSERT (errno == EBADF);
403 #endif
404
405 /* Cleanup. */
406 ASSERT (close (fd) == 0);
407 ASSERT (unlink (file) == 0);
408
409 return 0;
410 }
411