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 /* mingw32 needs ffs for compilations without optimization. */
 171 int ffs(int i)
 172 {
 173     /* Use gcc's builtin ffs. */
 174     return __builtin_ffs(i);
 175 }
 176
 177 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 178 #define _W32_FT_OFFSET (116444736000000000ULL)
 179
 180 int qemu_gettimeofday(qemu_timeval *tp)
 181 {
 182   union {
 183     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 184     FILETIME ft;
 185   }  _now;
 186
 187   if(tp)
 188     {
 189       GetSystemTimeAsFileTime (&_now.ft);
 190       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 191       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 192     }
 193   /* Always return 0 as per Open Group Base Specifications Issue 6.
 194      Do not set errno on error.  */
 195   return 0;
 196 }
 197 #endif /* _WIN32 */
 198
 199
 200 #ifdef _WIN32
 201 void socket_set_nonblock(int fd)
 202 {
 203     unsigned long opt = 1;
 204     ioctlsocket(fd, FIONBIO, &opt);
 205 }
 206
 207 int inet_aton(const char *cp, struct in_addr *ia)
 208 {
 209     uint32_t addr = inet_addr(cp);
 210     if (addr == 0xffffffff)
 211         return 0;
 212     ia->s_addr = addr;
 213     return 1;
 214 }
 215
 216 void qemu_set_cloexec(int fd)
 217 {
 218 }
 219
 220 #else
 221
 222 void socket_set_nonblock(int fd)
 223 {
 224     int f;
 225     f = fcntl(fd, F_GETFL);
 226     fcntl(fd, F_SETFL, f | O_NONBLOCK);
 227 }
 228
 229 void qemu_set_cloexec(int fd)
 230 {
 231     int f;
 232     f = fcntl(fd, F_GETFD);
 233     fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 234 }
 235
 236 #endif
 237
 238 /*
 239  * Opens a file with FD_CLOEXEC set
 240  */
 241 int qemu_open(const char *name, int flags, ...)
 242 {
 243     int ret;
 244     int mode = 0;
 245
 246     if (flags & O_CREAT) {
 247         va_list ap;
 248
 249         va_start(ap, flags);
 250         mode = va_arg(ap, int);
 251         va_end(ap);
 252     }
 253
 254 #ifdef O_CLOEXEC
 255     ret = open(name, flags | O_CLOEXEC, mode);
 256 #else
 257     ret = open(name, flags, mode);
 258     if (ret >= 0) {
 259         qemu_set_cloexec(ret);
 260     }
 261 #endif
 262
 263     return ret;
 264 }
 265
 266 /*
 267  * A variant of write(2) which handles partial write.
 268  *
 269  * Return the number of bytes transferred.
 270  * Set errno if fewer than `count' bytes are written.
 271  *
 272  * This function don't work with non-blocking fd's.
 273  * Any of the possibilities with non-bloking fd's is bad:
 274  *   - return a short write (then name is wrong)
 275  *   - busy wait adding (errno == EAGAIN) to the loop
 276  */
 277 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 278 {
 279     ssize_t ret = 0;
 280     ssize_t total = 0;
 281
 282     while (count) {
 283         ret = write(fd, buf, count);
 284         if (ret < 0) {
 285             if (errno == EINTR)
 286                 continue;
 287             break;
 288         }
 289
 290         count -= ret;
 291         buf += ret;
 292         total += ret;
 293     }
 294
 295     return total;
 296 }
 297
 298 #ifndef _WIN32
 299 /*
 300  * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
 301  */
 302 int qemu_eventfd(int fds[2])
 303 {
 304 #ifdef CONFIG_EVENTFD
 305     int ret;
 306
 307     ret = eventfd(0, 0);
 308     if (ret >= 0) {
 309         fds[0] = ret;
 310         qemu_set_cloexec(ret);
 311         if ((fds[1] = dup(ret)) == -1) {
 312             close(ret);
 313             return -1;
 314         }
 315         qemu_set_cloexec(fds[1]);
 316         return 0;
 317     }
 318
 319     if (errno != ENOSYS) {
 320         return -1;
 321     }
 322 #endif
 323
 324     return qemu_pipe(fds);
 325 }
 326
 327 /*
 328  * Creates a pipe with FD_CLOEXEC set on both file descriptors
 329  */
 330 int qemu_pipe(int pipefd[2])
 331 {
 332     int ret;
 333
 334 #ifdef CONFIG_PIPE2
 335     ret = pipe2(pipefd, O_CLOEXEC);
 336     if (ret != -1 || errno != ENOSYS) {
 337         return ret;
 338     }
 339 #endif
 340     ret = pipe(pipefd);
 341     if (ret == 0) {
 342         qemu_set_cloexec(pipefd[0]);
 343         qemu_set_cloexec(pipefd[1]);
 344     }
 345
 346     return ret;
 347 }
 348 #endif
 349
 350 /*
 351  * Opens a socket with FD_CLOEXEC set
 352  */
 353 int qemu_socket(int domain, int type, int protocol)
 354 {
 355     int ret;
 356
 357 #ifdef SOCK_CLOEXEC
 358     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 359     if (ret != -1 || errno != EINVAL) {
 360         return ret;
 361     }
 362 #endif
 363     ret = socket(domain, type, protocol);
 364     if (ret >= 0) {
 365         qemu_set_cloexec(ret);
 366     }
 367
 368     return ret;
 369 }
 370
 371 /*
 372  * Accept a connection and set FD_CLOEXEC
 373  */
 374 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 375 {
 376     int ret;
 377
 378 #ifdef CONFIG_ACCEPT4
 379     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 380     if (ret != -1 || errno != ENOSYS) {
 381         return ret;
 382     }
 383 #endif
 384     ret = accept(s, addr, addrlen);
 385     if (ret >= 0) {
 386         qemu_set_cloexec(ret);
 387     }
 388
 389     return ret;
 390 }