util/oslib-win32.c

   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
  29 #include "qemu/osdep.h"
  30 #include <windows.h>
  31 #include "qapi/error.h"
  32 #include "qemu/main-loop.h"
  33 #include "trace.h"
  34 #include "qemu/sockets.h"
  35 #include "qemu/cutils.h"
  36 #include "qemu/error-report.h"
  37 #include <malloc.h>
  38
  39 static int get_allocation_granularity(void)
  40 {
  41     SYSTEM_INFO system_info;
  42
  43     GetSystemInfo(&system_info);
  44     return system_info.dwAllocationGranularity;
  45 }
  46
  47 void *qemu_anon_ram_alloc(size_t size, uint64_t *align, bool shared,
  48                           bool noreserve)
  49 {
  50     void *ptr;
  51
  52     if (noreserve) {
  53         /*
  54          * We need a MEM_COMMIT before accessing any memory in a MEM_RESERVE
  55          * area; we cannot easily mimic POSIX MAP_NORESERVE semantics.
  56          */
  57         error_report("Skipping reservation of swap space is not supported.");
  58         return NULL;
  59     }
  60
  61     ptr = VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE);
  62     trace_qemu_anon_ram_alloc(size, ptr);
  63
  64     if (ptr && align) {
  65         *align = MAX(get_allocation_granularity(), getpagesize());
  66     }
  67     return ptr;
  68 }
  69
  70 void qemu_anon_ram_free(void *ptr, size_t size)
  71 {
  72     trace_qemu_anon_ram_free(ptr, size);
  73     if (ptr) {
  74         VirtualFree(ptr, 0, MEM_RELEASE);
  75     }
  76 }
  77
  78 #ifndef _POSIX_THREAD_SAFE_FUNCTIONS
  79 /* FIXME: add proper locking */
  80 struct tm *gmtime_r(const time_t *timep, struct tm *result)
  81 {
  82     struct tm *p = gmtime(timep);
  83     memset(result, 0, sizeof(*result));
  84     if (p) {
  85         *result = *p;
  86         p = result;
  87     }
  88     return p;
  89 }
  90
  91 /* FIXME: add proper locking */
  92 struct tm *localtime_r(const time_t *timep, struct tm *result)
  93 {
  94     struct tm *p = localtime(timep);
  95     memset(result, 0, sizeof(*result));
  96     if (p) {
  97         *result = *p;
  98         p = result;
  99     }
 100     return p;
 101 }
 102 #endif /* _POSIX_THREAD_SAFE_FUNCTIONS */
 103
 104 static int socket_error(void)
 105 {
 106     switch (WSAGetLastError()) {
 107     case 0:
 108         return 0;
 109     case WSAEINTR:
 110         return EINTR;
 111     case WSAEINVAL:
 112         return EINVAL;
 113     case WSA_INVALID_HANDLE:
 114         return EBADF;
 115     case WSA_NOT_ENOUGH_MEMORY:
 116         return ENOMEM;
 117     case WSA_INVALID_PARAMETER:
 118         return EINVAL;
 119     case WSAENAMETOOLONG:
 120         return ENAMETOOLONG;
 121     case WSAENOTEMPTY:
 122         return ENOTEMPTY;
 123     case WSAEWOULDBLOCK:
 124          /* not using EWOULDBLOCK as we don't want code to have
 125           * to check both EWOULDBLOCK and EAGAIN */
 126         return EAGAIN;
 127     case WSAEINPROGRESS:
 128         return EINPROGRESS;
 129     case WSAEALREADY:
 130         return EALREADY;
 131     case WSAENOTSOCK:
 132         return ENOTSOCK;
 133     case WSAEDESTADDRREQ:
 134         return EDESTADDRREQ;
 135     case WSAEMSGSIZE:
 136         return EMSGSIZE;
 137     case WSAEPROTOTYPE:
 138         return EPROTOTYPE;
 139     case WSAENOPROTOOPT:
 140         return ENOPROTOOPT;
 141     case WSAEPROTONOSUPPORT:
 142         return EPROTONOSUPPORT;
 143     case WSAEOPNOTSUPP:
 144         return EOPNOTSUPP;
 145     case WSAEAFNOSUPPORT:
 146         return EAFNOSUPPORT;
 147     case WSAEADDRINUSE:
 148         return EADDRINUSE;
 149     case WSAEADDRNOTAVAIL:
 150         return EADDRNOTAVAIL;
 151     case WSAENETDOWN:
 152         return ENETDOWN;
 153     case WSAENETUNREACH:
 154         return ENETUNREACH;
 155     case WSAENETRESET:
 156         return ENETRESET;
 157     case WSAECONNABORTED:
 158         return ECONNABORTED;
 159     case WSAECONNRESET:
 160         return ECONNRESET;
 161     case WSAENOBUFS:
 162         return ENOBUFS;
 163     case WSAEISCONN:
 164         return EISCONN;
 165     case WSAENOTCONN:
 166         return ENOTCONN;
 167     case WSAETIMEDOUT:
 168         return ETIMEDOUT;
 169     case WSAECONNREFUSED:
 170         return ECONNREFUSED;
 171     case WSAELOOP:
 172         return ELOOP;
 173     case WSAEHOSTUNREACH:
 174         return EHOSTUNREACH;
 175     default:
 176         return EIO;
 177     }
 178 }
 179
 180 void qemu_socket_set_block(int fd)
 181 {
 182     unsigned long opt = 0;
 183     qemu_socket_unselect(fd, NULL);
 184     ioctlsocket(fd, FIONBIO, &opt);
 185 }
 186
 187 int qemu_socket_try_set_nonblock(int fd)
 188 {
 189     unsigned long opt = 1;
 190     if (ioctlsocket(fd, FIONBIO, &opt) != NO_ERROR) {
 191         return -socket_error();
 192     }
 193     return 0;
 194 }
 195
 196 void qemu_socket_set_nonblock(int fd)
 197 {
 198     (void)qemu_socket_try_set_nonblock(fd);
 199 }
 200
 201 int socket_set_fast_reuse(int fd)
 202 {
 203     /* Enabling the reuse of an endpoint that was used by a socket still in
 204      * TIME_WAIT state is usually performed by setting SO_REUSEADDR. On Windows
 205      * fast reuse is the default and SO_REUSEADDR does strange things. So we
 206      * don't have to do anything here. More info can be found at:
 207      * http://msdn.microsoft.com/en-us/library/windows/desktop/ms740621.aspx */
 208     return 0;
 209 }
 210
 211 int inet_aton(const char *cp, struct in_addr *ia)
 212 {
 213     uint32_t addr = inet_addr(cp);
 214     if (addr == 0xffffffff) {
 215         return 0;
 216     }
 217     ia->s_addr = addr;
 218     return 1;
 219 }
 220
 221 void qemu_set_cloexec(int fd)
 222 {
 223 }
 224
 225 int qemu_get_thread_id(void)
 226 {
 227     return GetCurrentThreadId();
 228 }
 229
 230 char *
 231 qemu_get_local_state_dir(void)
 232 {
 233     const char * const *data_dirs = g_get_system_data_dirs();
 234
 235     g_assert(data_dirs && data_dirs[0]);
 236
 237     return g_strdup(data_dirs[0]);
 238 }
 239
 240 void qemu_set_tty_echo(int fd, bool echo)
 241 {
 242     HANDLE handle = (HANDLE)_get_osfhandle(fd);
 243     DWORD dwMode = 0;
 244
 245     if (handle == INVALID_HANDLE_VALUE) {
 246         return;
 247     }
 248
 249     GetConsoleMode(handle, &dwMode);
 250
 251     if (echo) {
 252         SetConsoleMode(handle, dwMode | ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT);
 253     } else {
 254         SetConsoleMode(handle,
 255                        dwMode & ~(ENABLE_ECHO_INPUT | ENABLE_LINE_INPUT));
 256     }
 257 }
 258
 259 int getpagesize(void)
 260 {
 261     SYSTEM_INFO system_info;
 262
 263     GetSystemInfo(&system_info);
 264     return system_info.dwPageSize;
 265 }
 266
 267 void qemu_prealloc_mem(int fd, char *area, size_t sz, int max_threads,
 268                        ThreadContext *tc, Error **errp)
 269 {
 270     int i;
 271     size_t pagesize = qemu_real_host_page_size();
 272
 273     sz = (sz + pagesize - 1) & -pagesize;
 274     for (i = 0; i < sz / pagesize; i++) {
 275         memset(area + pagesize * i, 0, 1);
 276     }
 277 }
 278
 279 char *qemu_get_pid_name(pid_t pid)
 280 {
 281     /* XXX Implement me */
 282     abort();
 283 }
 284
 285
 286 bool qemu_socket_select(int sockfd, WSAEVENT hEventObject,
 287                         long lNetworkEvents, Error **errp)
 288 {
 289     SOCKET s = _get_osfhandle(sockfd);
 290
 291     if (errp == NULL) {
 292         errp = &error_warn;
 293     }
 294
 295     if (s == INVALID_SOCKET) {
 296         error_setg(errp, "invalid socket fd=%d", sockfd);
 297         return false;
 298     }
 299
 300     if (WSAEventSelect(s, hEventObject, lNetworkEvents) != 0) {
 301         error_setg_win32(errp, WSAGetLastError(), "failed to WSAEventSelect()");
 302         return false;
 303     }
 304
 305     return true;
 306 }
 307
 308 bool qemu_socket_unselect(int sockfd, Error **errp)
 309 {
 310     return qemu_socket_select(sockfd, NULL, 0, errp);
 311 }
 312
 313 int qemu_socketpair(int domain, int type, int protocol, int sv[2])
 314 {
 315     struct sockaddr_un addr = {
 316         0,
 317     };
 318     socklen_t socklen;
 319     int listener = -1;
 320     int client = -1;
 321     int server = -1;
 322     g_autofree char *path = NULL;
 323     int tmpfd;
 324     u_long arg;
 325     int ret = -1;
 326
 327     g_return_val_if_fail(sv != NULL, -1);
 328
 329     addr.sun_family = AF_UNIX;
 330     socklen = sizeof(addr);
 331
 332     tmpfd = g_file_open_tmp(NULL, &path, NULL);
 333     if (tmpfd == -1 || !path) {
 334         errno = EACCES;
 335         goto out;
 336     }
 337
 338     close(tmpfd);
 339
 340     if (strlen(path) >= sizeof(addr.sun_path)) {
 341         errno = EINVAL;
 342         goto out;
 343     }
 344
 345     strncpy(addr.sun_path, path, sizeof(addr.sun_path) - 1);
 346
 347     listener = socket(domain, type, protocol);
 348     if (listener == -1) {
 349         goto out;
 350     }
 351
 352     if (DeleteFile(path) == 0 && GetLastError() != ERROR_FILE_NOT_FOUND) {
 353         errno = EACCES;
 354         goto out;
 355     }
 356     g_clear_pointer(&path, g_free);
 357
 358     if (bind(listener, (struct sockaddr *)&addr, socklen) == -1) {
 359         goto out;
 360     }
 361
 362     if (listen(listener, 1) == -1) {
 363         goto out;
 364     }
 365
 366     client = socket(domain, type, protocol);
 367     if (client == -1) {
 368         goto out;
 369     }
 370
 371     arg = 1;
 372     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
 373         goto out;
 374     }
 375
 376     if (connect(client, (struct sockaddr *)&addr, socklen) == -1 &&
 377         WSAGetLastError() != WSAEWOULDBLOCK) {
 378         goto out;
 379     }
 380
 381     server = accept(listener, NULL, NULL);
 382     if (server == -1) {
 383         goto out;
 384     }
 385
 386     arg = 0;
 387     if (ioctlsocket(client, FIONBIO, &arg) != NO_ERROR) {
 388         goto out;
 389     }
 390
 391     arg = 0;
 392     if (ioctlsocket(client, SIO_AF_UNIX_GETPEERPID, &arg) != NO_ERROR) {
 393         goto out;
 394     }
 395
 396     if (arg != GetCurrentProcessId()) {
 397         errno = EPERM;
 398         goto out;
 399     }
 400
 401     sv[0] = server;
 402     server = -1;
 403     sv[1] = client;
 404     client = -1;
 405     ret = 0;
 406
 407 out:
 408     if (listener != -1) {
 409         close(listener);
 410     }
 411     if (client != -1) {
 412         close(client);
 413     }
 414     if (server != -1) {
 415         close(server);
 416     }
 417     if (path) {
 418         DeleteFile(path);
 419     }
 420     return ret;
 421 }
 422
 423 #undef connect
 424 int qemu_connect_wrap(int sockfd, const struct sockaddr *addr,
 425                       socklen_t addrlen)
 426 {
 427     int ret;
 428     SOCKET s = _get_osfhandle(sockfd);
 429
 430     if (s == INVALID_SOCKET) {
 431         return -1;
 432     }
 433
 434     ret = connect(s, addr, addrlen);
 435     if (ret < 0) {
 436         if (WSAGetLastError() == WSAEWOULDBLOCK) {
 437             errno = EINPROGRESS;
 438         } else {
 439             errno = socket_error();
 440         }
 441     }
 442     return ret;
 443 }
 444
 445
 446 #undef listen
 447 int qemu_listen_wrap(int sockfd, int backlog)
 448 {
 449     int ret;
 450     SOCKET s = _get_osfhandle(sockfd);
 451
 452     if (s == INVALID_SOCKET) {
 453         return -1;
 454     }
 455
 456     ret = listen(s, backlog);
 457     if (ret < 0) {
 458         errno = socket_error();
 459     }
 460     return ret;
 461 }
 462
 463
 464 #undef bind
 465 int qemu_bind_wrap(int sockfd, const struct sockaddr *addr,
 466                    socklen_t addrlen)
 467 {
 468     int ret;
 469     SOCKET s = _get_osfhandle(sockfd);
 470
 471     if (s == INVALID_SOCKET) {
 472         return -1;
 473     }
 474
 475     ret = bind(s, addr, addrlen);
 476     if (ret < 0) {
 477         errno = socket_error();
 478     }
 479     return ret;
 480 }
 481
 482
 483 #undef close
 484 int qemu_close_wrap(int fd)
 485 {
 486     int ret;
 487     DWORD flags = 0;
 488     SOCKET s = INVALID_SOCKET;
 489
 490     if (fd_is_socket(fd)) {
 491         s = _get_osfhandle(fd);
 492
 493         /*
 494          * If we were to just call _close on the descriptor, it would close the
 495          * HANDLE, but it wouldn't free any of the resources associated to the
 496          * SOCKET, and we can't call _close after calling closesocket, because
 497          * closesocket has already closed the HANDLE, and _close would attempt to
 498          * close the HANDLE again, resulting in a double free. We can however
 499          * protect the HANDLE from actually being closed long enough to close the
 500          * file descriptor, then close the socket itself.
 501          */
 502         if (!GetHandleInformation((HANDLE)s, &flags)) {
 503             errno = EACCES;
 504             return -1;
 505         }
 506
 507         if (!SetHandleInformation((HANDLE)s, HANDLE_FLAG_PROTECT_FROM_CLOSE, HANDLE_FLAG_PROTECT_FROM_CLOSE)) {
 508             errno = EACCES;
 509             return -1;
 510         }
 511     }
 512
 513     ret = close(fd);
 514
 515     if (s != INVALID_SOCKET && !SetHandleInformation((HANDLE)s, flags, flags)) {
 516         errno = EACCES;
 517         return -1;
 518     }
 519
 520     /*
 521      * close() returns EBADF since we PROTECT_FROM_CLOSE the underlying handle,
 522      * but the FD is actually freed
 523      */
 524     if (ret < 0 && (s == INVALID_SOCKET || errno != EBADF)) {
 525         return ret;
 526     }
 527
 528     if (s != INVALID_SOCKET) {
 529         ret = closesocket(s);
 530         if (ret < 0) {
 531             errno = socket_error();
 532         }
 533     }
 534
 535     return ret;
 536 }
 537
 538
 539 #undef socket
 540 int qemu_socket_wrap(int domain, int type, int protocol)
 541 {
 542     SOCKET s;
 543     int fd;
 544
 545     s = socket(domain, type, protocol);
 546     if (s == -1) {
 547         errno = socket_error();
 548         return -1;
 549     }
 550
 551     fd = _open_osfhandle(s, _O_BINARY);
 552     if (fd < 0) {
 553         closesocket(s);
 554         /* _open_osfhandle may not set errno, and closesocket() may override it */
 555         errno = ENOMEM;
 556     }
 557
 558     return fd;
 559 }
 560
 561
 562 #undef accept
 563 int qemu_accept_wrap(int sockfd, struct sockaddr *addr,
 564                      socklen_t *addrlen)
 565 {
 566     int fd;
 567     SOCKET s = _get_osfhandle(sockfd);
 568
 569     if (s == INVALID_SOCKET) {
 570         return -1;
 571     }
 572
 573     s = accept(s, addr, addrlen);
 574     if (s == -1) {
 575         errno = socket_error();
 576         return -1;
 577     }
 578
 579     fd = _open_osfhandle(s, _O_BINARY);
 580     if (fd < 0) {
 581         closesocket(s);
 582         /* _open_osfhandle may not set errno, and closesocket() may override it */
 583         errno = ENOMEM;
 584     }
 585
 586     return fd;
 587 }
 588
 589
 590 #undef shutdown
 591 int qemu_shutdown_wrap(int sockfd, int how)
 592 {
 593     int ret;
 594     SOCKET s = _get_osfhandle(sockfd);
 595
 596     if (s == INVALID_SOCKET) {
 597         return -1;
 598     }
 599
 600     ret = shutdown(s, how);
 601     if (ret < 0) {
 602         errno = socket_error();
 603     }
 604     return ret;
 605 }
 606
 607
 608 #undef ioctlsocket
 609 int qemu_ioctlsocket_wrap(int fd, int req, void *val)
 610 {
 611     int ret;
 612     SOCKET s = _get_osfhandle(fd);
 613
 614     if (s == INVALID_SOCKET) {
 615         return -1;
 616     }
 617
 618     ret = ioctlsocket(s, req, val);
 619     if (ret < 0) {
 620         errno = socket_error();
 621     }
 622     return ret;
 623 }
 624
 625
 626 #undef getsockopt
 627 int qemu_getsockopt_wrap(int sockfd, int level, int optname,
 628                          void *optval, socklen_t *optlen)
 629 {
 630     int ret;
 631     SOCKET s = _get_osfhandle(sockfd);
 632
 633     if (s == INVALID_SOCKET) {
 634         return -1;
 635     }
 636
 637     ret = getsockopt(s, level, optname, optval, optlen);
 638     if (ret < 0) {
 639         errno = socket_error();
 640     }
 641     return ret;
 642 }
 643
 644
 645 #undef setsockopt
 646 int qemu_setsockopt_wrap(int sockfd, int level, int optname,
 647                          const void *optval, socklen_t optlen)
 648 {
 649     int ret;
 650     SOCKET s = _get_osfhandle(sockfd);
 651
 652     if (s == INVALID_SOCKET) {
 653         return -1;
 654     }
 655
 656     ret = setsockopt(s, level, optname, optval, optlen);
 657     if (ret < 0) {
 658         errno = socket_error();
 659     }
 660     return ret;
 661 }
 662
 663
 664 #undef getpeername
 665 int qemu_getpeername_wrap(int sockfd, struct sockaddr *addr,
 666                           socklen_t *addrlen)
 667 {
 668     int ret;
 669     SOCKET s = _get_osfhandle(sockfd);
 670
 671     if (s == INVALID_SOCKET) {
 672         return -1;
 673     }
 674
 675     ret = getpeername(s, addr, addrlen);
 676     if (ret < 0) {
 677         errno = socket_error();
 678     }
 679     return ret;
 680 }
 681
 682
 683 #undef getsockname
 684 int qemu_getsockname_wrap(int sockfd, struct sockaddr *addr,
 685                           socklen_t *addrlen)
 686 {
 687     int ret;
 688     SOCKET s = _get_osfhandle(sockfd);
 689
 690     if (s == INVALID_SOCKET) {
 691         return -1;
 692     }
 693
 694     ret = getsockname(s, addr, addrlen);
 695     if (ret < 0) {
 696         errno = socket_error();
 697     }
 698     return ret;
 699 }
 700
 701
 702 #undef send
 703 ssize_t qemu_send_wrap(int sockfd, const void *buf, size_t len, int flags)
 704 {
 705     int ret;
 706     SOCKET s = _get_osfhandle(sockfd);
 707
 708     if (s == INVALID_SOCKET) {
 709         return -1;
 710     }
 711
 712     ret = send(s, buf, len, flags);
 713     if (ret < 0) {
 714         errno = socket_error();
 715     }
 716     return ret;
 717 }
 718
 719
 720 #undef sendto
 721 ssize_t qemu_sendto_wrap(int sockfd, const void *buf, size_t len, int flags,
 722                          const struct sockaddr *addr, socklen_t addrlen)
 723 {
 724     int ret;
 725     SOCKET s = _get_osfhandle(sockfd);
 726
 727     if (s == INVALID_SOCKET) {
 728         return -1;
 729     }
 730
 731     ret = sendto(s, buf, len, flags, addr, addrlen);
 732     if (ret < 0) {
 733         errno = socket_error();
 734     }
 735     return ret;
 736 }
 737
 738
 739 #undef recv
 740 ssize_t qemu_recv_wrap(int sockfd, void *buf, size_t len, int flags)
 741 {
 742     int ret;
 743     SOCKET s = _get_osfhandle(sockfd);
 744
 745     if (s == INVALID_SOCKET) {
 746         return -1;
 747     }
 748
 749     ret = recv(s, buf, len, flags);
 750     if (ret < 0) {
 751         errno = socket_error();
 752     }
 753     return ret;
 754 }
 755
 756
 757 #undef recvfrom
 758 ssize_t qemu_recvfrom_wrap(int sockfd, void *buf, size_t len, int flags,
 759                            struct sockaddr *addr, socklen_t *addrlen)
 760 {
 761     int ret;
 762     SOCKET s = _get_osfhandle(sockfd);
 763
 764     if (s == INVALID_SOCKET) {
 765         return -1;
 766     }
 767
 768     ret = recvfrom(s, buf, len, flags, addr, addrlen);
 769     if (ret < 0) {
 770         errno = socket_error();
 771     }
 772     return ret;
 773 }
 774
 775 bool qemu_write_pidfile(const char *filename, Error **errp)
 776 {
 777     char buffer[128];
 778     int len;
 779     HANDLE file;
 780     OVERLAPPED overlap;
 781     BOOL ret;
 782     memset(&overlap, 0, sizeof(overlap));
 783
 784     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
 785                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 786
 787     if (file == INVALID_HANDLE_VALUE) {
 788         error_setg(errp, "Failed to create PID file");
 789         return false;
 790     }
 791     len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", (pid_t)getpid());
 792     ret = WriteFile(file, (LPCVOID)buffer, (DWORD)len,
 793                     NULL, &overlap);
 794     CloseHandle(file);
 795     if (ret == 0) {
 796         error_setg(errp, "Failed to write PID file");
 797         return false;
 798     }
 799     return true;
 800 }
 801
 802 size_t qemu_get_host_physmem(void)
 803 {
 804     MEMORYSTATUSEX statex;
 805     statex.dwLength = sizeof(statex);
 806
 807     if (GlobalMemoryStatusEx(&statex)) {
 808         return statex.ullTotalPhys;
 809     }
 810     return 0;
 811 }
 812
 813 int qemu_msync(void *addr, size_t length, int fd)
 814 {
 815     /**
 816      * Perform the sync based on the file descriptor
 817      * The sync range will most probably be wider than the one
 818      * requested - but it will still get the job done
 819      */
 820     return qemu_fdatasync(fd);
 821 }