util: rename qemu_open() to qemu_open_old()
[qemu.git] / util / osdep.c
1 /*
2 * QEMU low level functions
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24 #include "qemu/osdep.h"
25
26 /* Needed early for CONFIG_BSD etc. */
27
28 #ifdef CONFIG_SOLARIS
29 #include <sys/statvfs.h>
30 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for
31 discussion about Solaris header problems */
32 extern int madvise(char *, size_t, int);
33 #endif
34
35 #include "qemu-common.h"
36 #include "qemu/cutils.h"
37 #include "qemu/sockets.h"
38 #include "qemu/error-report.h"
39 #include "monitor/monitor.h"
40
41 static bool fips_enabled = false;
42
43 static const char *hw_version = QEMU_HW_VERSION;
44
45 int socket_set_cork(int fd, int v)
46 {
47 #if defined(SOL_TCP) && defined(TCP_CORK)
48 return qemu_setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v));
49 #else
50 return 0;
51 #endif
52 }
53
54 int socket_set_nodelay(int fd)
55 {
56 int v = 1;
57 return qemu_setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &v, sizeof(v));
58 }
59
60 int qemu_madvise(void *addr, size_t len, int advice)
61 {
62 if (advice == QEMU_MADV_INVALID) {
63 errno = EINVAL;
64 return -1;
65 }
66 #if defined(CONFIG_MADVISE)
67 return madvise(addr, len, advice);
68 #elif defined(CONFIG_POSIX_MADVISE)
69 return posix_madvise(addr, len, advice);
70 #else
71 errno = EINVAL;
72 return -1;
73 #endif
74 }
75
76 static int qemu_mprotect__osdep(void *addr, size_t size, int prot)
77 {
78 g_assert(!((uintptr_t)addr & ~qemu_real_host_page_mask));
79 g_assert(!(size & ~qemu_real_host_page_mask));
80
81 #ifdef _WIN32
82 DWORD old_protect;
83
84 if (!VirtualProtect(addr, size, prot, &old_protect)) {
85 g_autofree gchar *emsg = g_win32_error_message(GetLastError());
86 error_report("%s: VirtualProtect failed: %s", __func__, emsg);
87 return -1;
88 }
89 return 0;
90 #else
91 if (mprotect(addr, size, prot)) {
92 error_report("%s: mprotect failed: %s", __func__, strerror(errno));
93 return -1;
94 }
95 return 0;
96 #endif
97 }
98
99 int qemu_mprotect_rwx(void *addr, size_t size)
100 {
101 #ifdef _WIN32
102 return qemu_mprotect__osdep(addr, size, PAGE_EXECUTE_READWRITE);
103 #else
104 return qemu_mprotect__osdep(addr, size, PROT_READ | PROT_WRITE | PROT_EXEC);
105 #endif
106 }
107
108 int qemu_mprotect_none(void *addr, size_t size)
109 {
110 #ifdef _WIN32
111 return qemu_mprotect__osdep(addr, size, PAGE_NOACCESS);
112 #else
113 return qemu_mprotect__osdep(addr, size, PROT_NONE);
114 #endif
115 }
116
117 #ifndef _WIN32
118
119 static int fcntl_op_setlk = -1;
120 static int fcntl_op_getlk = -1;
121
122 /*
123 * Dups an fd and sets the flags
124 */
125 int qemu_dup_flags(int fd, int flags)
126 {
127 int ret;
128 int serrno;
129 int dup_flags;
130
131 ret = qemu_dup(fd);
132 if (ret == -1) {
133 goto fail;
134 }
135
136 dup_flags = fcntl(ret, F_GETFL);
137 if (dup_flags == -1) {
138 goto fail;
139 }
140
141 if ((flags & O_SYNC) != (dup_flags & O_SYNC)) {
142 errno = EINVAL;
143 goto fail;
144 }
145
146 /* Set/unset flags that we can with fcntl */
147 if (fcntl(ret, F_SETFL, flags) == -1) {
148 goto fail;
149 }
150
151 /* Truncate the file in the cases that open() would truncate it */
152 if (flags & O_TRUNC ||
153 ((flags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))) {
154 if (ftruncate(ret, 0) == -1) {
155 goto fail;
156 }
157 }
158
159 return ret;
160
161 fail:
162 serrno = errno;
163 if (ret != -1) {
164 close(ret);
165 }
166 errno = serrno;
167 return -1;
168 }
169
170 int qemu_dup(int fd)
171 {
172 int ret;
173 #ifdef F_DUPFD_CLOEXEC
174 ret = fcntl(fd, F_DUPFD_CLOEXEC, 0);
175 #else
176 ret = dup(fd);
177 if (ret != -1) {
178 qemu_set_cloexec(ret);
179 }
180 #endif
181 return ret;
182 }
183
184 static int qemu_parse_fdset(const char *param)
185 {
186 return qemu_parse_fd(param);
187 }
188
189 static void qemu_probe_lock_ops(void)
190 {
191 if (fcntl_op_setlk == -1) {
192 #ifdef F_OFD_SETLK
193 int fd;
194 int ret;
195 struct flock fl = {
196 .l_whence = SEEK_SET,
197 .l_start = 0,
198 .l_len = 0,
199 .l_type = F_WRLCK,
200 };
201
202 fd = open("/dev/null", O_RDWR);
203 if (fd < 0) {
204 fprintf(stderr,
205 "Failed to open /dev/null for OFD lock probing: %s\n",
206 strerror(errno));
207 fcntl_op_setlk = F_SETLK;
208 fcntl_op_getlk = F_GETLK;
209 return;
210 }
211 ret = fcntl(fd, F_OFD_GETLK, &fl);
212 close(fd);
213 if (!ret) {
214 fcntl_op_setlk = F_OFD_SETLK;
215 fcntl_op_getlk = F_OFD_GETLK;
216 } else {
217 fcntl_op_setlk = F_SETLK;
218 fcntl_op_getlk = F_GETLK;
219 }
220 #else
221 fcntl_op_setlk = F_SETLK;
222 fcntl_op_getlk = F_GETLK;
223 #endif
224 }
225 }
226
227 bool qemu_has_ofd_lock(void)
228 {
229 qemu_probe_lock_ops();
230 #ifdef F_OFD_SETLK
231 return fcntl_op_setlk == F_OFD_SETLK;
232 #else
233 return false;
234 #endif
235 }
236
237 static int qemu_lock_fcntl(int fd, int64_t start, int64_t len, int fl_type)
238 {
239 int ret;
240 struct flock fl = {
241 .l_whence = SEEK_SET,
242 .l_start = start,
243 .l_len = len,
244 .l_type = fl_type,
245 };
246 qemu_probe_lock_ops();
247 do {
248 ret = fcntl(fd, fcntl_op_setlk, &fl);
249 } while (ret == -1 && errno == EINTR);
250 return ret == -1 ? -errno : 0;
251 }
252
253 int qemu_lock_fd(int fd, int64_t start, int64_t len, bool exclusive)
254 {
255 return qemu_lock_fcntl(fd, start, len, exclusive ? F_WRLCK : F_RDLCK);
256 }
257
258 int qemu_unlock_fd(int fd, int64_t start, int64_t len)
259 {
260 return qemu_lock_fcntl(fd, start, len, F_UNLCK);
261 }
262
263 int qemu_lock_fd_test(int fd, int64_t start, int64_t len, bool exclusive)
264 {
265 int ret;
266 struct flock fl = {
267 .l_whence = SEEK_SET,
268 .l_start = start,
269 .l_len = len,
270 .l_type = exclusive ? F_WRLCK : F_RDLCK,
271 };
272 qemu_probe_lock_ops();
273 ret = fcntl(fd, fcntl_op_getlk, &fl);
274 if (ret == -1) {
275 return -errno;
276 } else {
277 return fl.l_type == F_UNLCK ? 0 : -EAGAIN;
278 }
279 }
280 #endif
281
282 static int qemu_open_cloexec(const char *name, int flags, mode_t mode)
283 {
284 int ret;
285 #ifdef O_CLOEXEC
286 ret = open(name, flags | O_CLOEXEC, mode);
287 #else
288 ret = open(name, flags, mode);
289 if (ret >= 0) {
290 qemu_set_cloexec(ret);
291 }
292 #endif
293 return ret;
294 }
295
296 /*
297 * Opens a file with FD_CLOEXEC set
298 */
299 int qemu_open_old(const char *name, int flags, ...)
300 {
301 int ret;
302 int mode = 0;
303
304 #ifndef _WIN32
305 const char *fdset_id_str;
306
307 /* Attempt dup of fd from fd set */
308 if (strstart(name, "/dev/fdset/", &fdset_id_str)) {
309 int64_t fdset_id;
310 int dupfd;
311
312 fdset_id = qemu_parse_fdset(fdset_id_str);
313 if (fdset_id == -1) {
314 errno = EINVAL;
315 return -1;
316 }
317
318 dupfd = monitor_fdset_dup_fd_add(fdset_id, flags);
319 if (dupfd == -1) {
320 return -1;
321 }
322
323 return dupfd;
324 }
325 #endif
326
327 if (flags & O_CREAT) {
328 va_list ap;
329
330 va_start(ap, flags);
331 mode = va_arg(ap, int);
332 va_end(ap);
333 }
334
335 ret = qemu_open_cloexec(name, flags, mode);
336
337 #ifdef O_DIRECT
338 if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) {
339 error_report("file system may not support O_DIRECT");
340 errno = EINVAL; /* in case it was clobbered */
341 }
342 #endif /* O_DIRECT */
343
344 return ret;
345 }
346
347 int qemu_close(int fd)
348 {
349 int64_t fdset_id;
350
351 /* Close fd that was dup'd from an fdset */
352 fdset_id = monitor_fdset_dup_fd_find(fd);
353 if (fdset_id != -1) {
354 int ret;
355
356 ret = close(fd);
357 if (ret == 0) {
358 monitor_fdset_dup_fd_remove(fd);
359 }
360
361 return ret;
362 }
363
364 return close(fd);
365 }
366
367 /*
368 * Delete a file from the filesystem, unless the filename is /dev/fdset/...
369 *
370 * Returns: On success, zero is returned. On error, -1 is returned,
371 * and errno is set appropriately.
372 */
373 int qemu_unlink(const char *name)
374 {
375 if (g_str_has_prefix(name, "/dev/fdset/")) {
376 return 0;
377 }
378
379 return unlink(name);
380 }
381
382 /*
383 * A variant of write(2) which handles partial write.
384 *
385 * Return the number of bytes transferred.
386 * Set errno if fewer than `count' bytes are written.
387 *
388 * This function don't work with non-blocking fd's.
389 * Any of the possibilities with non-bloking fd's is bad:
390 * - return a short write (then name is wrong)
391 * - busy wait adding (errno == EAGAIN) to the loop
392 */
393 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
394 {
395 ssize_t ret = 0;
396 ssize_t total = 0;
397
398 while (count) {
399 ret = write(fd, buf, count);
400 if (ret < 0) {
401 if (errno == EINTR)
402 continue;
403 break;
404 }
405
406 count -= ret;
407 buf += ret;
408 total += ret;
409 }
410
411 return total;
412 }
413
414 /*
415 * Opens a socket with FD_CLOEXEC set
416 */
417 int qemu_socket(int domain, int type, int protocol)
418 {
419 int ret;
420
421 #ifdef SOCK_CLOEXEC
422 ret = socket(domain, type | SOCK_CLOEXEC, protocol);
423 if (ret != -1 || errno != EINVAL) {
424 return ret;
425 }
426 #endif
427 ret = socket(domain, type, protocol);
428 if (ret >= 0) {
429 qemu_set_cloexec(ret);
430 }
431
432 return ret;
433 }
434
435 /*
436 * Accept a connection and set FD_CLOEXEC
437 */
438 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
439 {
440 int ret;
441
442 #ifdef CONFIG_ACCEPT4
443 ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
444 if (ret != -1 || errno != ENOSYS) {
445 return ret;
446 }
447 #endif
448 ret = accept(s, addr, addrlen);
449 if (ret >= 0) {
450 qemu_set_cloexec(ret);
451 }
452
453 return ret;
454 }
455
456 void qemu_set_hw_version(const char *version)
457 {
458 hw_version = version;
459 }
460
461 const char *qemu_hw_version(void)
462 {
463 return hw_version;
464 }
465
466 void fips_set_state(bool requested)
467 {
468 #ifdef __linux__
469 if (requested) {
470 FILE *fds = fopen("/proc/sys/crypto/fips_enabled", "r");
471 if (fds != NULL) {
472 fips_enabled = (fgetc(fds) == '1');
473 fclose(fds);
474 }
475 }
476 #else
477 fips_enabled = false;
478 #endif /* __linux__ */
479
480 #ifdef _FIPS_DEBUG
481 fprintf(stderr, "FIPS mode %s (requested %s)\n",
482 (fips_enabled ? "enabled" : "disabled"),
483 (requested ? "enabled" : "disabled"));
484 #endif
485 }
486
487 bool fips_get_state(void)
488 {
489 return fips_enabled;
490 }
491
492 #ifdef _WIN32
493 static void socket_cleanup(void)
494 {
495 WSACleanup();
496 }
497 #endif
498
499 int socket_init(void)
500 {
501 #ifdef _WIN32
502 WSADATA Data;
503 int ret, err;
504
505 ret = WSAStartup(MAKEWORD(2, 2), &Data);
506 if (ret != 0) {
507 err = WSAGetLastError();
508 fprintf(stderr, "WSAStartup: %d\n", err);
509 return -1;
510 }
511 atexit(socket_cleanup);
512 #endif
513 return 0;
514 }
515
516
517 #ifndef CONFIG_IOVEC
518 /* helper function for iov_send_recv() */
519 static ssize_t
520 readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)
521 {
522 unsigned i = 0;
523 ssize_t ret = 0;
524 while (i < iov_cnt) {
525 ssize_t r = do_write
526 ? write(fd, iov[i].iov_base, iov[i].iov_len)
527 : read(fd, iov[i].iov_base, iov[i].iov_len);
528 if (r > 0) {
529 ret += r;
530 } else if (!r) {
531 break;
532 } else if (errno == EINTR) {
533 continue;
534 } else {
535 /* else it is some "other" error,
536 * only return if there was no data processed. */
537 if (ret == 0) {
538 ret = -1;
539 }
540 break;
541 }
542 i++;
543 }
544 return ret;
545 }
546
547 ssize_t
548 readv(int fd, const struct iovec *iov, int iov_cnt)
549 {
550 return readv_writev(fd, iov, iov_cnt, false);
551 }
552
553 ssize_t
554 writev(int fd, const struct iovec *iov, int iov_cnt)
555 {
556 return readv_writev(fd, iov, iov_cnt, true);
557 }
558 #endif