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 <stdlib.h>
  25 #include <stdio.h>
  26 #include <stdarg.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <unistd.h>
  30 #include <fcntl.h>
  31
  32 /* Needed early for CONFIG_BSD etc. */
  33 #include "config-host.h"
  34
  35 #ifdef CONFIG_SOLARIS
  36 #include <sys/types.h>
  37 #include <sys/statvfs.h>
  38 #endif
  39
  40 #ifdef CONFIG_EVENTFD
  41 #include <sys/eventfd.h>
  42 #endif
  43
  44 #ifdef _WIN32
  45 #include <windows.h>
  46 #elif defined(CONFIG_BSD)
  47 #include <stdlib.h>
  48 #else
  49 #include <malloc.h>
  50 #endif
  51
  52 #include "qemu-common.h"
  53 #include "sysemu.h"
  54 #include "qemu_socket.h"
  55
  56 #if !defined(_POSIX_C_SOURCE) || defined(_WIN32) || defined(__sun__)
  57 static void *oom_check(void *ptr)
  58 {
  59     if (ptr == NULL) {
  60 #if defined(_WIN32)
  61         fprintf(stderr, "Failed to allocate memory: %lu\n", GetLastError());
  62 #else
  63         fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
  64 #endif
  65         abort();
  66     }
  67     return ptr;
  68 }
  69 #endif
  70
  71 #if defined(_WIN32)
  72 void *qemu_memalign(size_t alignment, size_t size)
  73 {
  74     if (!size) {
  75         abort();
  76     }
  77     return oom_check(VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE));
  78 }
  79
  80 void *qemu_vmalloc(size_t size)
  81 {
  82     /* FIXME: this is not exactly optimal solution since VirtualAlloc
  83        has 64Kb granularity, but at least it guarantees us that the
  84        memory is page aligned. */
  85     if (!size) {
  86         abort();
  87     }
  88     return oom_check(VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE));
  89 }
  90
  91 void qemu_vfree(void *ptr)
  92 {
  93     VirtualFree(ptr, 0, MEM_RELEASE);
  94 }
  95
  96 #else
  97
  98 void *qemu_memalign(size_t alignment, size_t size)
  99 {
 100 #if defined(_POSIX_C_SOURCE) && !defined(__sun__)
 101     int ret;
 102     void *ptr;
 103     ret = posix_memalign(&ptr, alignment, size);
 104     if (ret != 0) {
 105         fprintf(stderr, "Failed to allocate %zu B: %s\n",
 106                 size, strerror(ret));
 107         abort();
 108     }
 109     return ptr;
 110 #elif defined(CONFIG_BSD)
 111     return oom_check(valloc(size));
 112 #else
 113     return oom_check(memalign(alignment, size));
 114 #endif
 115 }
 116
 117 /* alloc shared memory pages */
 118 void *qemu_vmalloc(size_t size)
 119 {
 120     return qemu_memalign(getpagesize(), size);
 121 }
 122
 123 void qemu_vfree(void *ptr)
 124 {
 125     free(ptr);
 126 }
 127
 128 #endif
 129
 130 int qemu_create_pidfile(const char *filename)
 131 {
 132     char buffer[128];
 133     int len;
 134 #ifndef _WIN32
 135     int fd;
 136
 137     fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
 138     if (fd == -1)
 139         return -1;
 140
 141     if (lockf(fd, F_TLOCK, 0) == -1)
 142         return -1;
 143
 144     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 145     if (write(fd, buffer, len) != len)
 146         return -1;
 147 #else
 148     HANDLE file;
 149     OVERLAPPED overlap;
 150     BOOL ret;
 151     memset(&overlap, 0, sizeof(overlap));
 152
 153     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
 154                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 155
 156     if (file == INVALID_HANDLE_VALUE)
 157       return -1;
 158
 159     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 160     ret = WriteFileEx(file, (LPCVOID)buffer, (DWORD)len,
 161                       &overlap, NULL);
 162     if (ret == 0)
 163       return -1;
 164 #endif
 165     return 0;
 166 }
 167
 168 #ifdef _WIN32
 169
 170 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 171 #define _W32_FT_OFFSET (116444736000000000ULL)
 172
 173 int qemu_gettimeofday(qemu_timeval *tp)
 174 {
 175   union {
 176     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 177     FILETIME ft;
 178   }  _now;
 179
 180   if(tp)
 181     {
 182       GetSystemTimeAsFileTime (&_now.ft);
 183       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 184       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 185     }
 186   /* Always return 0 as per Open Group Base Specifications Issue 6.
 187      Do not set errno on error.  */
 188   return 0;
 189 }
 190 #endif /* _WIN32 */
 191
 192
 193 #ifdef _WIN32
 194 void socket_set_nonblock(int fd)
 195 {
 196     unsigned long opt = 1;
 197     ioctlsocket(fd, FIONBIO, &opt);
 198 }
 199
 200 int inet_aton(const char *cp, struct in_addr *ia)
 201 {
 202     uint32_t addr = inet_addr(cp);
 203     if (addr == 0xffffffff)
 204         return 0;
 205     ia->s_addr = addr;
 206     return 1;
 207 }
 208
 209 void qemu_set_cloexec(int fd)
 210 {
 211 }
 212
 213 #else
 214
 215 void socket_set_nonblock(int fd)
 216 {
 217     int f;
 218     f = fcntl(fd, F_GETFL);
 219     fcntl(fd, F_SETFL, f | O_NONBLOCK);
 220 }
 221
 222 void qemu_set_cloexec(int fd)
 223 {
 224     int f;
 225     f = fcntl(fd, F_GETFD);
 226     fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 227 }
 228
 229 #endif
 230
 231 /*
 232  * Opens a file with FD_CLOEXEC set
 233  */
 234 int qemu_open(const char *name, int flags, ...)
 235 {
 236     int ret;
 237     int mode = 0;
 238
 239     if (flags & O_CREAT) {
 240         va_list ap;
 241
 242         va_start(ap, flags);
 243         mode = va_arg(ap, int);
 244         va_end(ap);
 245     }
 246
 247 #ifdef O_CLOEXEC
 248     ret = open(name, flags | O_CLOEXEC, mode);
 249 #else
 250     ret = open(name, flags, mode);
 251     if (ret >= 0) {
 252         qemu_set_cloexec(ret);
 253     }
 254 #endif
 255
 256     return ret;
 257 }
 258
 259 /*
 260  * A variant of write(2) which handles partial write.
 261  *
 262  * Return the number of bytes transferred.
 263  * Set errno if fewer than `count' bytes are written.
 264  *
 265  * This function don't work with non-blocking fd's.
 266  * Any of the possibilities with non-bloking fd's is bad:
 267  *   - return a short write (then name is wrong)
 268  *   - busy wait adding (errno == EAGAIN) to the loop
 269  */
 270 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 271 {
 272     ssize_t ret = 0;
 273     ssize_t total = 0;
 274
 275     while (count) {
 276         ret = write(fd, buf, count);
 277         if (ret < 0) {
 278             if (errno == EINTR)
 279                 continue;
 280             break;
 281         }
 282
 283         count -= ret;
 284         buf += ret;
 285         total += ret;
 286     }
 287
 288     return total;
 289 }
 290
 291 #ifndef _WIN32
 292 /*
 293  * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
 294  */
 295 int qemu_eventfd(int fds[2])
 296 {
 297 #ifdef CONFIG_EVENTFD
 298     int ret;
 299
 300     ret = eventfd(0, 0);
 301     if (ret >= 0) {
 302         fds[0] = ret;
 303         qemu_set_cloexec(ret);
 304         if ((fds[1] = dup(ret)) == -1) {
 305             close(ret);
 306             return -1;
 307         }
 308         qemu_set_cloexec(fds[1]);
 309         return 0;
 310     }
 311
 312     if (errno != ENOSYS) {
 313         return -1;
 314     }
 315 #endif
 316
 317     return qemu_pipe(fds);
 318 }
 319
 320 /*
 321  * Creates a pipe with FD_CLOEXEC set on both file descriptors
 322  */
 323 int qemu_pipe(int pipefd[2])
 324 {
 325     int ret;
 326
 327 #ifdef CONFIG_PIPE2
 328     ret = pipe2(pipefd, O_CLOEXEC);
 329     if (ret != -1 || errno != ENOSYS) {
 330         return ret;
 331     }
 332 #endif
 333     ret = pipe(pipefd);
 334     if (ret == 0) {
 335         qemu_set_cloexec(pipefd[0]);
 336         qemu_set_cloexec(pipefd[1]);
 337     }
 338
 339     return ret;
 340 }
 341 #endif
 342
 343 /*
 344  * Opens a socket with FD_CLOEXEC set
 345  */
 346 int qemu_socket(int domain, int type, int protocol)
 347 {
 348     int ret;
 349
 350 #ifdef SOCK_CLOEXEC
 351     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 352     if (ret != -1 || errno != EINVAL) {
 353         return ret;
 354     }
 355 #endif
 356     ret = socket(domain, type, protocol);
 357     if (ret >= 0) {
 358         qemu_set_cloexec(ret);
 359     }
 360
 361     return ret;
 362 }
 363
 364 /*
 365  * Accept a connection and set FD_CLOEXEC
 366  */
 367 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 368 {
 369     int ret;
 370
 371 #ifdef CONFIG_ACCEPT4
 372     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 373     if (ret != -1 || errno != ENOSYS) {
 374         return ret;
 375     }
 376 #endif
 377     ret = accept(s, addr, addrlen);
 378     if (ret >= 0) {
 379         qemu_set_cloexec(ret);
 380     }
 381
 382     return ret;
 383 }