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24#include "qemu/osdep.h"
25#include "qapi/error.h"
26#include "qemu/cutils.h"
27#include "qemu/sockets.h"
28#include "qemu/error-report.h"
29#include "qemu/madvise.h"
30#include "qemu/mprotect.h"
31#include "qemu/hw-version.h"
32#include "monitor/monitor.h"
33
34static const char *hw_version = QEMU_HW_VERSION;
35
36int socket_set_cork(int fd, int v)
37{
38#if defined(SOL_TCP) && defined(TCP_CORK)
39 return setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v));
40#else
41 return 0;
42#endif
43}
44
45int socket_set_nodelay(int fd)
46{
47 int v = 1;
48 return setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &v, sizeof(v));
49}
50
51int qemu_madvise(void *addr, size_t len, int advice)
52{
53 if (advice == QEMU_MADV_INVALID) {
54 errno = EINVAL;
55 return -1;
56 }
57#if defined(CONFIG_MADVISE)
58 return madvise(addr, len, advice);
59#elif defined(CONFIG_POSIX_MADVISE)
60 return posix_madvise(addr, len, advice);
61#else
62 errno = EINVAL;
63 return -1;
64#endif
65}
66
67static int qemu_mprotect__osdep(void *addr, size_t size, int prot)
68{
69 g_assert(!((uintptr_t)addr & ~qemu_real_host_page_mask()));
70 g_assert(!(size & ~qemu_real_host_page_mask()));
71
72#ifdef _WIN32
73 DWORD old_protect;
74
75 if (!VirtualProtect(addr, size, prot, &old_protect)) {
76 g_autofree gchar *emsg = g_win32_error_message(GetLastError());
77 error_report("%s: VirtualProtect failed: %s", __func__, emsg);
78 return -1;
79 }
80 return 0;
81#else
82 if (mprotect(addr, size, prot)) {
83 error_report("%s: mprotect failed: %s", __func__, strerror(errno));
84 return -1;
85 }
86 return 0;
87#endif
88}
89
90int qemu_mprotect_rw(void *addr, size_t size)
91{
92#ifdef _WIN32
93 return qemu_mprotect__osdep(addr, size, PAGE_READWRITE);
94#else
95 return qemu_mprotect__osdep(addr, size, PROT_READ | PROT_WRITE);
96#endif
97}
98
99int 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
108int 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
119static int fcntl_op_setlk = -1;
120static int fcntl_op_getlk = -1;
121
122
123
124
125int 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
147 if (fcntl(ret, F_SETFL, flags) == -1) {
148 goto fail;
149 }
150
151
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
161fail:
162 serrno = errno;
163 if (ret != -1) {
164 close(ret);
165 }
166 errno = serrno;
167 return -1;
168}
169
170int 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
184static int qemu_parse_fdset(const char *param)
185{
186 return qemu_parse_fd(param);
187}
188
189static 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
227bool 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
237static 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
253int 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
258int qemu_unlock_fd(int fd, int64_t start, int64_t len)
259{
260 return qemu_lock_fcntl(fd, start, len, F_UNLCK);
261}
262
263int 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
282static 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
298
299static int
300qemu_open_internal(const char *name, int flags, mode_t mode, Error **errp)
301{
302 int ret;
303
304#ifndef _WIN32
305 const char *fdset_id_str;
306
307
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 error_setg(errp, "Could not parse fdset %s", name);
315 errno = EINVAL;
316 return -1;
317 }
318
319 dupfd = monitor_fdset_dup_fd_add(fdset_id, flags);
320 if (dupfd == -1) {
321 error_setg_errno(errp, errno, "Could not dup FD for %s flags %x",
322 name, flags);
323 return -1;
324 }
325
326 return dupfd;
327 }
328#endif
329
330 ret = qemu_open_cloexec(name, flags, mode);
331
332 if (ret == -1) {
333 const char *action = flags & O_CREAT ? "create" : "open";
334#ifdef O_DIRECT
335
336 if (errno == EINVAL && (flags & O_DIRECT)) {
337 ret = open(name, flags & ~O_DIRECT, mode);
338 if (ret != -1) {
339 close(ret);
340 error_setg(errp, "Could not %s '%s': "
341 "filesystem does not support O_DIRECT",
342 action, name);
343 errno = EINVAL;
344 return -1;
345 }
346 }
347#endif
348 error_setg_errno(errp, errno, "Could not %s '%s'",
349 action, name);
350 }
351
352 return ret;
353}
354
355
356int qemu_open(const char *name, int flags, Error **errp)
357{
358 assert(!(flags & O_CREAT));
359
360 return qemu_open_internal(name, flags, 0, errp);
361}
362
363
364int qemu_create(const char *name, int flags, mode_t mode, Error **errp)
365{
366 assert(!(flags & O_CREAT));
367
368 return qemu_open_internal(name, flags | O_CREAT, mode, errp);
369}
370
371
372int qemu_open_old(const char *name, int flags, ...)
373{
374 va_list ap;
375 mode_t mode = 0;
376 int ret;
377
378 va_start(ap, flags);
379 if (flags & O_CREAT) {
380 mode = va_arg(ap, int);
381 }
382 va_end(ap);
383
384 ret = qemu_open_internal(name, flags, mode, NULL);
385
386#ifdef O_DIRECT
387 if (ret == -1 && errno == EINVAL && (flags & O_DIRECT)) {
388 error_report("file system may not support O_DIRECT");
389 errno = EINVAL;
390 }
391#endif
392
393 return ret;
394}
395
396int qemu_close(int fd)
397{
398 int64_t fdset_id;
399
400
401 fdset_id = monitor_fdset_dup_fd_find(fd);
402 if (fdset_id != -1) {
403 int ret;
404
405 ret = close(fd);
406 if (ret == 0) {
407 monitor_fdset_dup_fd_remove(fd);
408 }
409
410 return ret;
411 }
412
413 return close(fd);
414}
415
416
417
418
419
420
421
422int qemu_unlink(const char *name)
423{
424 if (g_str_has_prefix(name, "/dev/fdset/")) {
425 return 0;
426 }
427
428 return unlink(name);
429}
430
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440
441
442ssize_t qemu_write_full(int fd, const void *buf, size_t count)
443{
444 ssize_t ret = 0;
445 ssize_t total = 0;
446
447 while (count) {
448 ret = write(fd, buf, count);
449 if (ret < 0) {
450 if (errno == EINTR)
451 continue;
452 break;
453 }
454
455 count -= ret;
456 buf += ret;
457 total += ret;
458 }
459
460 return total;
461}
462
463
464
465
466int qemu_socket(int domain, int type, int protocol)
467{
468 int ret;
469
470#ifdef SOCK_CLOEXEC
471 ret = socket(domain, type | SOCK_CLOEXEC, protocol);
472 if (ret != -1 || errno != EINVAL) {
473 return ret;
474 }
475#endif
476 ret = socket(domain, type, protocol);
477 if (ret >= 0) {
478 qemu_set_cloexec(ret);
479 }
480
481 return ret;
482}
483
484
485
486
487int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
488{
489 int ret;
490
491#ifdef CONFIG_ACCEPT4
492 ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
493 if (ret != -1 || errno != ENOSYS) {
494 return ret;
495 }
496#endif
497 ret = accept(s, addr, addrlen);
498 if (ret >= 0) {
499 qemu_set_cloexec(ret);
500 }
501
502 return ret;
503}
504
505void qemu_set_hw_version(const char *version)
506{
507 hw_version = version;
508}
509
510const char *qemu_hw_version(void)
511{
512 return hw_version;
513}
514
515#ifdef _WIN32
516static void socket_cleanup(void)
517{
518 WSACleanup();
519}
520#endif
521
522int socket_init(void)
523{
524#ifdef _WIN32
525 WSADATA Data;
526 int ret, err;
527
528 ret = WSAStartup(MAKEWORD(2, 2), &Data);
529 if (ret != 0) {
530 err = WSAGetLastError();
531 fprintf(stderr, "WSAStartup: %d\n", err);
532 return -1;
533 }
534 atexit(socket_cleanup);
535#endif
536 return 0;
537}
538
539
540#ifndef CONFIG_IOVEC
541
542static ssize_t
543readv_writev(int fd, const struct iovec *iov, int iov_cnt, bool do_write)
544{
545 unsigned i = 0;
546 ssize_t ret = 0;
547 while (i < iov_cnt) {
548 ssize_t r = do_write
549 ? write(fd, iov[i].iov_base, iov[i].iov_len)
550 : read(fd, iov[i].iov_base, iov[i].iov_len);
551 if (r > 0) {
552 ret += r;
553 } else if (!r) {
554 break;
555 } else if (errno == EINTR) {
556 continue;
557 } else {
558
559
560 if (ret == 0) {
561 ret = -1;
562 }
563 break;
564 }
565 i++;
566 }
567 return ret;
568}
569
570ssize_t
571readv(int fd, const struct iovec *iov, int iov_cnt)
572{
573 return readv_writev(fd, iov, iov_cnt, false);
574}
575
576ssize_t
577writev(int fd, const struct iovec *iov, int iov_cnt)
578{
579 return readv_writev(fd, iov, iov_cnt, true);
580}
581#endif
582
583
584
585
586
587
588
589
590int qemu_fdatasync(int fd)
591{
592#ifdef CONFIG_FDATASYNC
593 return fdatasync(fd);
594#else
595 return fsync(fd);
596#endif
597}
598