xref: /openbmc/qemu/util/oslib-win32.c (revision 500eb6db)
1 /*
2  * os-win32.c
3  *
4  * Copyright (c) 2003-2008 Fabrice Bellard
5  * Copyright (c) 2010-2016 Red Hat, Inc.
6  *
7  * QEMU library functions for win32 which are shared between QEMU and
8  * the QEMU tools.
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining a copy
11  * of this software and associated documentation files (the "Software"), to deal
12  * in the Software without restriction, including without limitation the rights
13  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
14  * copies of the Software, and to permit persons to whom the Software is
15  * furnished to do so, subject to the following conditions:
16  *
17  * The above copyright notice and this permission notice shall be included in
18  * all copies or substantial portions of the Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
21  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
23  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
24  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
25  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
26  * THE SOFTWARE.
27  *
28  * The implementation of g_poll (functions poll_rest, g_poll) at the end of
29  * this file are based on code from GNOME glib-2 and use a different license,
30  * see the license comment there.
31  */
32 
33 #include "qemu/osdep.h"
34 #include <windows.h>
35 #include "qemu-common.h"
36 #include "qapi/error.h"
37 #include "sysemu/sysemu.h"
38 #include "qemu/main-loop.h"
39 #include "trace.h"
40 #include "qemu/sockets.h"
41 #include "qemu/cutils.h"
42 
43 /* this must come after including "trace.h" */
44 #include <shlobj.h>
45 
46 void *qemu_oom_check(void *ptr)
47 {
48     if (ptr == NULL) {
49         fprintf(stderr, "Failed to allocate memory: %lu\n", GetLastError());
50         abort();
51     }
52     return ptr;
53 }
54 
55 void *qemu_try_memalign(size_t alignment, size_t size)
56 {
57     void *ptr;
58 
59     if (!size) {
60         abort();
61     }
62     ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
63     trace_qemu_memalign(alignment, size, ptr);
64     return ptr;
65 }
66 
67 void *qemu_memalign(size_t alignment, size_t size)
68 {
69     return qemu_oom_check(qemu_try_memalign(alignment, size));
70 }
71 
72 static int get_allocation_granularity(void)
73 {
74     SYSTEM_INFO system_info;
75 
76     GetSystemInfo(&system_info);
77     return system_info.dwAllocationGranularity;
78 }
79 
80 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared)
81 {
82     void *ptr;
83 
84     ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
85     trace_qemu_anon_ram_alloc(size, ptr);
86 
87     if (ptr && align) {
88         *align = MAX(get_allocation_granularity(), getpagesize());
89     }
90     return ptr;
91 }
92 
93 void qemu_vfree(void *ptr)
94 {
95     trace_qemu_vfree(ptr);
96     if (ptr) {
97         VirtualFree(ptr, 0, MEM_RELEASE);
98     }
99 }
100 
101 void qemu_anon_ram_free(void *ptr, size_t size)
102 {
103     trace_qemu_anon_ram_free(ptr, size);
104     if (ptr) {
105         VirtualFree(ptr, 0, MEM_RELEASE);
106     }
107 }
108 
109 #ifndef CONFIG_LOCALTIME_R
110 /* FIXME: add proper locking */
111 struct tm *gmtime_r(const time_t *timep, struct tm *result)
112 {
113     struct tm *p = gmtime(timep);
114     memset(result, 0, sizeof(*result));
115     if (p) {
116         *result = *p;
117         p = result;
118     }
119     return p;
120 }
121 
122 /* FIXME: add proper locking */
123 struct tm *localtime_r(const time_t *timep, struct tm *result)
124 {
125     struct tm *p = localtime(timep);
126     memset(result, 0, sizeof(*result));
127     if (p) {
128         *result = *p;
129         p = result;
130     }
131     return p;
132 }
133 #endif /* CONFIG_LOCALTIME_R */
134 
135 void qemu_set_block(int fd)
136 {
137     unsigned long opt = 0;
138     WSAEventSelect(fd, NULL, 0);
139     ioctlsocket(fd, FIONBIO, &opt);
140 }
141 
142 void qemu_set_nonblock(int fd)
143 {
144     unsigned long opt = 1;
145     ioctlsocket(fd, FIONBIO, &opt);
146     qemu_fd_register(fd);
147 }
148 
149 int socket_set_fast_reuse(int fd)
150 {
151     /* Enabling the reuse of an endpoint that was used by a socket still in
152      * TIME_WAIT state is usually performed by setting SO_REUSEADDR. On Windows
153      * fast reuse is the default and SO_REUSEADDR does strange things. So we
154      * don't have to do anything here. More info can be found at:
155      * http://msdn.microsoft.com/en-us/library/windows/desktop/ms740621.aspx */
156     return 0;
157 }
158 
159 
160 static int socket_error(void)
161 {
162     switch (WSAGetLastError()) {
163     case 0:
164         return 0;
165     case WSAEINTR:
166         return EINTR;
167     case WSAEINVAL:
168         return EINVAL;
169     case WSA_INVALID_HANDLE:
170         return EBADF;
171     case WSA_NOT_ENOUGH_MEMORY:
172         return ENOMEM;
173     case WSA_INVALID_PARAMETER:
174         return EINVAL;
175     case WSAENAMETOOLONG:
176         return ENAMETOOLONG;
177     case WSAENOTEMPTY:
178         return ENOTEMPTY;
179     case WSAEWOULDBLOCK:
180          /* not using EWOULDBLOCK as we don't want code to have
181           * to check both EWOULDBLOCK and EAGAIN */
182         return EAGAIN;
183     case WSAEINPROGRESS:
184         return EINPROGRESS;
185     case WSAEALREADY:
186         return EALREADY;
187     case WSAENOTSOCK:
188         return ENOTSOCK;
189     case WSAEDESTADDRREQ:
190         return EDESTADDRREQ;
191     case WSAEMSGSIZE:
192         return EMSGSIZE;
193     case WSAEPROTOTYPE:
194         return EPROTOTYPE;
195     case WSAENOPROTOOPT:
196         return ENOPROTOOPT;
197     case WSAEPROTONOSUPPORT:
198         return EPROTONOSUPPORT;
199     case WSAEOPNOTSUPP:
200         return EOPNOTSUPP;
201     case WSAEAFNOSUPPORT:
202         return EAFNOSUPPORT;
203     case WSAEADDRINUSE:
204         return EADDRINUSE;
205     case WSAEADDRNOTAVAIL:
206         return EADDRNOTAVAIL;
207     case WSAENETDOWN:
208         return ENETDOWN;
209     case WSAENETUNREACH:
210         return ENETUNREACH;
211     case WSAENETRESET:
212         return ENETRESET;
213     case WSAECONNABORTED:
214         return ECONNABORTED;
215     case WSAECONNRESET:
216         return ECONNRESET;
217     case WSAENOBUFS:
218         return ENOBUFS;
219     case WSAEISCONN:
220         return EISCONN;
221     case WSAENOTCONN:
222         return ENOTCONN;
223     case WSAETIMEDOUT:
224         return ETIMEDOUT;
225     case WSAECONNREFUSED:
226         return ECONNREFUSED;
227     case WSAELOOP:
228         return ELOOP;
229     case WSAEHOSTUNREACH:
230         return EHOSTUNREACH;
231     default:
232         return EIO;
233     }
234 }
235 
236 int inet_aton(const char *cp, struct in_addr *ia)
237 {
238     uint32_t addr = inet_addr(cp);
239     if (addr == 0xffffffff) {
240         return 0;
241     }
242     ia->s_addr = addr;
243     return 1;
244 }
245 
246 void qemu_set_cloexec(int fd)
247 {
248 }
249 
250 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
251 #define _W32_FT_OFFSET (116444736000000000ULL)
252 
253 int qemu_gettimeofday(qemu_timeval *tp)
254 {
255   union {
256     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
257     FILETIME ft;
258   }  _now;
259 
260   if(tp) {
261       GetSystemTimeAsFileTime (&_now.ft);
262       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
263       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
264   }
265   /* Always return 0 as per Open Group Base Specifications Issue 6.
266      Do not set errno on error.  */
267   return 0;
268 }
269 
270 int qemu_get_thread_id(void)
271 {
272     return GetCurrentThreadId();
273 }
274 
275 char *
276 qemu_get_local_state_pathname(const char *relative_pathname)
277 {
278     HRESULT result;
279     char base_path[MAX_PATH+1] = "";
280 
281     result = SHGetFolderPath(NULL, CSIDL_COMMON_APPDATA, NULL,
282                              /* SHGFP_TYPE_CURRENT */ 0, base_path);
283     if (result != S_OK) {
284         /* misconfigured environment */
285         g_critical("CSIDL_COMMON_APPDATA unavailable: %ld", (long)result);
286         abort();
287     }
288     return g_strdup_printf("%s" G_DIR_SEPARATOR_S "%s", base_path,
289                            relative_pathname);
290 }
291 
292 void qemu_set_tty_echo(int fd, bool echo)
293 {
294     HANDLE handle = (HANDLE)_get_osfhandle(fd);
295     DWORD dwMode = 0;
296 
297     if (handle == INVALID_HANDLE_VALUE) {
298         return;
299     }
300 
301     GetConsoleMode(handle, &dwMode);
302 
303     if (echo) {
304         SetConsoleMode(handle, dwMode | ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT);
305     } else {
306         SetConsoleMode(handle,
307                        dwMode & ~(ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT));
308     }
309 }
310 
311 static char exec_dir[PATH_MAX];
312 
313 void qemu_init_exec_dir(const char *argv0)
314 {
315 
316     char *p;
317     char buf[MAX_PATH];
318     DWORD len;
319 
320     len = GetModuleFileName(NULL, buf, sizeof(buf) - 1);
321     if (len == 0) {
322         return;
323     }
324 
325     buf[len] = 0;
326     p = buf + len - 1;
327     while (p != buf && *p != '\\') {
328         p--;
329     }
330     *p = 0;
331     if (access(buf, R_OK) == 0) {
332         pstrcpy(exec_dir, sizeof(exec_dir), buf);
333     }
334 }
335 
336 char *qemu_get_exec_dir(void)
337 {
338     return g_strdup(exec_dir);
339 }
340 
341 #if !GLIB_CHECK_VERSION(2, 50, 0)
342 /*
343  * The original implementation of g_poll from glib has a problem on Windows
344  * when using timeouts < 10 ms.
345  *
346  * Whenever g_poll is called with timeout < 10 ms, it does a quick poll instead
347  * of wait. This causes significant performance degradation of QEMU.
348  *
349  * The following code is a copy of the original code from glib/gpoll.c
350  * (glib commit 20f4d1820b8d4d0fc4447188e33efffd6d4a88d8 from 2014-02-19).
351  * Some debug code was removed and the code was reformatted.
352  * All other code modifications are marked with 'QEMU'.
353  */
354 
355 /*
356  * gpoll.c: poll(2) abstraction
357  * Copyright 1998 Owen Taylor
358  * Copyright 2008 Red Hat, Inc.
359  *
360  * This library is free software; you can redistribute it and/or
361  * modify it under the terms of the GNU Lesser General Public
362  * License as published by the Free Software Foundation; either
363  * version 2 of the License, or (at your option) any later version.
364  *
365  * This library is distributed in the hope that it will be useful,
366  * but WITHOUT ANY WARRANTY; without even the implied warranty of
367  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
368  * Lesser General Public License for more details.
369  *
370  * You should have received a copy of the GNU Lesser General Public
371  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
372  */
373 
374 static int poll_rest(gboolean poll_msgs, HANDLE *handles, gint nhandles,
375                      GPollFD *fds, guint nfds, gint timeout)
376 {
377     DWORD ready;
378     GPollFD *f;
379     int recursed_result;
380 
381     if (poll_msgs) {
382         /* Wait for either messages or handles
383          * -> Use MsgWaitForMultipleObjectsEx
384          */
385         ready = MsgWaitForMultipleObjectsEx(nhandles, handles, timeout,
386                                             QS_ALLINPUT, MWMO_ALERTABLE);
387 
388         if (ready == WAIT_FAILED) {
389             gchar *emsg = g_win32_error_message(GetLastError());
390             g_warning("MsgWaitForMultipleObjectsEx failed: %s", emsg);
391             g_free(emsg);
392         }
393     } else if (nhandles == 0) {
394         /* No handles to wait for, just the timeout */
395         if (timeout == INFINITE) {
396             ready = WAIT_FAILED;
397         } else {
398             SleepEx(timeout, TRUE);
399             ready = WAIT_TIMEOUT;
400         }
401     } else {
402         /* Wait for just handles
403          * -> Use WaitForMultipleObjectsEx
404          */
405         ready =
406             WaitForMultipleObjectsEx(nhandles, handles, FALSE, timeout, TRUE);
407         if (ready == WAIT_FAILED) {
408             gchar *emsg = g_win32_error_message(GetLastError());
409             g_warning("WaitForMultipleObjectsEx failed: %s", emsg);
410             g_free(emsg);
411         }
412     }
413 
414     if (ready == WAIT_FAILED) {
415         return -1;
416     } else if (ready == WAIT_TIMEOUT || ready == WAIT_IO_COMPLETION) {
417         return 0;
418     } else if (poll_msgs && ready == WAIT_OBJECT_0 + nhandles) {
419         for (f = fds; f < &fds[nfds]; ++f) {
420             if (f->fd == G_WIN32_MSG_HANDLE && f->events & G_IO_IN) {
421                 f->revents |= G_IO_IN;
422             }
423         }
424 
425         /* If we have a timeout, or no handles to poll, be satisfied
426          * with just noticing we have messages waiting.
427          */
428         if (timeout != 0 || nhandles == 0) {
429             return 1;
430         }
431 
432         /* If no timeout and handles to poll, recurse to poll them,
433          * too.
434          */
435         recursed_result = poll_rest(FALSE, handles, nhandles, fds, nfds, 0);
436         return (recursed_result == -1) ? -1 : 1 + recursed_result;
437     } else if (/* QEMU: removed the following unneeded statement which causes
438                 * a compiler warning: ready >= WAIT_OBJECT_0 && */
439                ready < WAIT_OBJECT_0 + nhandles) {
440         for (f = fds; f < &fds[nfds]; ++f) {
441             if ((HANDLE) f->fd == handles[ready - WAIT_OBJECT_0]) {
442                 f->revents = f->events;
443             }
444         }
445 
446         /* If no timeout and polling several handles, recurse to poll
447          * the rest of them.
448          */
449         if (timeout == 0 && nhandles > 1) {
450             /* Remove the handle that fired */
451             int i;
452             for (i = ready - WAIT_OBJECT_0 + 1; i < nhandles; i++) {
453                 handles[i-1] = handles[i];
454             }
455             nhandles--;
456             recursed_result = poll_rest(FALSE, handles, nhandles, fds, nfds, 0);
457             return (recursed_result == -1) ? -1 : 1 + recursed_result;
458         }
459         return 1;
460     }
461 
462     return 0;
463 }
464 
465 gint g_poll(GPollFD *fds, guint nfds, gint timeout)
466 {
467     HANDLE handles[MAXIMUM_WAIT_OBJECTS];
468     gboolean poll_msgs = FALSE;
469     GPollFD *f;
470     gint nhandles = 0;
471     int retval;
472 
473     for (f = fds; f < &fds[nfds]; ++f) {
474         if (f->fd == G_WIN32_MSG_HANDLE && (f->events & G_IO_IN)) {
475             poll_msgs = TRUE;
476         } else if (f->fd > 0) {
477             /* Don't add the same handle several times into the array, as
478              * docs say that is not allowed, even if it actually does seem
479              * to work.
480              */
481             gint i;
482 
483             for (i = 0; i < nhandles; i++) {
484                 if (handles[i] == (HANDLE) f->fd) {
485                     break;
486                 }
487             }
488 
489             if (i == nhandles) {
490                 if (nhandles == MAXIMUM_WAIT_OBJECTS) {
491                     g_warning("Too many handles to wait for!\n");
492                     break;
493                 } else {
494                     handles[nhandles++] = (HANDLE) f->fd;
495                 }
496             }
497         }
498     }
499 
500     for (f = fds; f < &fds[nfds]; ++f) {
501         f->revents = 0;
502     }
503 
504     if (timeout == -1) {
505         timeout = INFINITE;
506     }
507 
508     /* Polling for several things? */
509     if (nhandles > 1 || (nhandles > 0 && poll_msgs)) {
510         /* First check if one or several of them are immediately
511          * available
512          */
513         retval = poll_rest(poll_msgs, handles, nhandles, fds, nfds, 0);
514 
515         /* If not, and we have a significant timeout, poll again with
516          * timeout then. Note that this will return indication for only
517          * one event, or only for messages. We ignore timeouts less than
518          * ten milliseconds as they are mostly pointless on Windows, the
519          * MsgWaitForMultipleObjectsEx() call will timeout right away
520          * anyway.
521          *
522          * Modification for QEMU: replaced timeout >= 10 by timeout > 0.
523          */
524         if (retval == 0 && (timeout == INFINITE || timeout > 0)) {
525             retval = poll_rest(poll_msgs, handles, nhandles,
526                                fds, nfds, timeout);
527         }
528     } else {
529         /* Just polling for one thing, so no need to check first if
530          * available immediately
531          */
532         retval = poll_rest(poll_msgs, handles, nhandles, fds, nfds, timeout);
533     }
534 
535     if (retval == -1) {
536         for (f = fds; f < &fds[nfds]; ++f) {
537             f->revents = 0;
538         }
539     }
540 
541     return retval;
542 }
543 #endif
544 
545 int getpagesize(void)
546 {
547     SYSTEM_INFO system_info;
548 
549     GetSystemInfo(&system_info);
550     return system_info.dwPageSize;
551 }
552 
553 void os_mem_prealloc(int fd, char *area, size_t memory, int smp_cpus,
554                      Error **errp)
555 {
556     int i;
557     size_t pagesize = getpagesize();
558 
559     memory = (memory + pagesize - 1) & -pagesize;
560     for (i = 0; i < memory / pagesize; i++) {
561         memset(area + pagesize * i, 0, 1);
562     }
563 }
564 
565 uint64_t qemu_get_pmem_size(const char *filename, Error **errp)
566 {
567     error_setg(errp, "pmem support not available");
568     return 0;
569 }
570 
571 char *qemu_get_pid_name(pid_t pid)
572 {
573     /* XXX Implement me */
574     abort();
575 }
576 
577 
578 pid_t qemu_fork(Error **errp)
579 {
580     errno = ENOSYS;
581     error_setg_errno(errp, errno,
582                      "cannot fork child process");
583     return -1;
584 }
585 
586 
587 #undef connect
588 int qemu_connect_wrap(int sockfd, const struct sockaddr *addr,
589                       socklen_t addrlen)
590 {
591     int ret;
592     ret = connect(sockfd, addr, addrlen);
593     if (ret < 0) {
594         errno = socket_error();
595     }
596     return ret;
597 }
598 
599 
600 #undef listen
601 int qemu_listen_wrap(int sockfd, int backlog)
602 {
603     int ret;
604     ret = listen(sockfd, backlog);
605     if (ret < 0) {
606         errno = socket_error();
607     }
608     return ret;
609 }
610 
611 
612 #undef bind
613 int qemu_bind_wrap(int sockfd, const struct sockaddr *addr,
614                    socklen_t addrlen)
615 {
616     int ret;
617     ret = bind(sockfd, addr, addrlen);
618     if (ret < 0) {
619         errno = socket_error();
620     }
621     return ret;
622 }
623 
624 
625 #undef socket
626 int qemu_socket_wrap(int domain, int type, int protocol)
627 {
628     int ret;
629     ret = socket(domain, type, protocol);
630     if (ret < 0) {
631         errno = socket_error();
632     }
633     return ret;
634 }
635 
636 
637 #undef accept
638 int qemu_accept_wrap(int sockfd, struct sockaddr *addr,
639                      socklen_t *addrlen)
640 {
641     int ret;
642     ret = accept(sockfd, addr, addrlen);
643     if (ret < 0) {
644         errno = socket_error();
645     }
646     return ret;
647 }
648 
649 
650 #undef shutdown
651 int qemu_shutdown_wrap(int sockfd, int how)
652 {
653     int ret;
654     ret = shutdown(sockfd, how);
655     if (ret < 0) {
656         errno = socket_error();
657     }
658     return ret;
659 }
660 
661 
662 #undef ioctlsocket
663 int qemu_ioctlsocket_wrap(int fd, int req, void *val)
664 {
665     int ret;
666     ret = ioctlsocket(fd, req, val);
667     if (ret < 0) {
668         errno = socket_error();
669     }
670     return ret;
671 }
672 
673 
674 #undef closesocket
675 int qemu_closesocket_wrap(int fd)
676 {
677     int ret;
678     ret = closesocket(fd);
679     if (ret < 0) {
680         errno = socket_error();
681     }
682     return ret;
683 }
684 
685 
686 #undef getsockopt
687 int qemu_getsockopt_wrap(int sockfd, int level, int optname,
688                          void *optval, socklen_t *optlen)
689 {
690     int ret;
691     ret = getsockopt(sockfd, level, optname, optval, optlen);
692     if (ret < 0) {
693         errno = socket_error();
694     }
695     return ret;
696 }
697 
698 
699 #undef setsockopt
700 int qemu_setsockopt_wrap(int sockfd, int level, int optname,
701                          const void *optval, socklen_t optlen)
702 {
703     int ret;
704     ret = setsockopt(sockfd, level, optname, optval, optlen);
705     if (ret < 0) {
706         errno = socket_error();
707     }
708     return ret;
709 }
710 
711 
712 #undef getpeername
713 int qemu_getpeername_wrap(int sockfd, struct sockaddr *addr,
714                           socklen_t *addrlen)
715 {
716     int ret;
717     ret = getpeername(sockfd, addr, addrlen);
718     if (ret < 0) {
719         errno = socket_error();
720     }
721     return ret;
722 }
723 
724 
725 #undef getsockname
726 int qemu_getsockname_wrap(int sockfd, struct sockaddr *addr,
727                           socklen_t *addrlen)
728 {
729     int ret;
730     ret = getsockname(sockfd, addr, addrlen);
731     if (ret < 0) {
732         errno = socket_error();
733     }
734     return ret;
735 }
736 
737 
738 #undef send
739 ssize_t qemu_send_wrap(int sockfd, const void *buf, size_t len, int flags)
740 {
741     int ret;
742     ret = send(sockfd, buf, len, flags);
743     if (ret < 0) {
744         errno = socket_error();
745     }
746     return ret;
747 }
748 
749 
750 #undef sendto
751 ssize_t qemu_sendto_wrap(int sockfd, const void *buf, size_t len, int flags,
752                          const struct sockaddr *addr, socklen_t addrlen)
753 {
754     int ret;
755     ret = sendto(sockfd, buf, len, flags, addr, addrlen);
756     if (ret < 0) {
757         errno = socket_error();
758     }
759     return ret;
760 }
761 
762 
763 #undef recv
764 ssize_t qemu_recv_wrap(int sockfd, void *buf, size_t len, int flags)
765 {
766     int ret;
767     ret = recv(sockfd, buf, len, flags);
768     if (ret < 0) {
769         errno = socket_error();
770     }
771     return ret;
772 }
773 
774 
775 #undef recvfrom
776 ssize_t qemu_recvfrom_wrap(int sockfd, void *buf, size_t len, int flags,
777                            struct sockaddr *addr, socklen_t *addrlen)
778 {
779     int ret;
780     ret = recvfrom(sockfd, buf, len, flags, addr, addrlen);
781     if (ret < 0) {
782         errno = socket_error();
783     }
784     return ret;
785 }
786 
787 bool qemu_write_pidfile(const char *filename, Error **errp)
788 {
789     char buffer[128];
790     int len;
791     HANDLE file;
792     OVERLAPPED overlap;
793     BOOL ret;
794     memset(&overlap, 0, sizeof(overlap));
795 
796     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
797                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
798 
799     if (file == INVALID_HANDLE_VALUE) {
800         error_setg(errp, "Failed to create PID file");
801         return false;
802     }
803     len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", (pid_t)getpid());
804     ret = WriteFile(file, (LPCVOID)buffer, (DWORD)len,
805                     NULL, &overlap);
806     CloseHandle(file);
807     if (ret == 0) {
808         error_setg(errp, "Failed to write PID file");
809         return false;
810     }
811     return true;
812 }
813