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 #ifndef __ia64__
 121     return qemu_memalign(getpagesize(), size);
 122 #else
 123     return qemu_memalign(65536, size);
 124 #endif
 125 }
 126
 127 void qemu_vfree(void *ptr)
 128 {
 129     free(ptr);
 130 }
 131
 132 #endif
 133
 134 int qemu_create_pidfile(const char *filename)
 135 {
 136     char buffer[128];
 137     int len;
 138 #ifndef _WIN32
 139     int fd;
 140
 141     fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
 142     if (fd == -1)
 143         return -1;
 144
 145     if (lockf(fd, F_TLOCK, 0) == -1)
 146         return -1;
 147
 148     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 149     if (write(fd, buffer, len) != len)
 150         return -1;
 151 #else
 152     HANDLE file;
 153     OVERLAPPED overlap;
 154     BOOL ret;
 155     memset(&overlap, 0, sizeof(overlap));
 156
 157     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
 158                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 159
 160     if (file == INVALID_HANDLE_VALUE)
 161       return -1;
 162
 163     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 164     ret = WriteFileEx(file, (LPCVOID)buffer, (DWORD)len,
 165                       &overlap, NULL);
 166     if (ret == 0)
 167       return -1;
 168 #endif
 169     return 0;
 170 }
 171
 172 #ifdef _WIN32
 173
 174 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 175 #define _W32_FT_OFFSET (116444736000000000ULL)
 176
 177 int qemu_gettimeofday(qemu_timeval *tp)
 178 {
 179   union {
 180     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 181     FILETIME ft;
 182   }  _now;
 183
 184   if(tp)
 185     {
 186       GetSystemTimeAsFileTime (&_now.ft);
 187       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 188       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 189     }
 190   /* Always return 0 as per Open Group Base Specifications Issue 6.
 191      Do not set errno on error.  */
 192   return 0;
 193 }
 194 #endif /* _WIN32 */
 195
 196
 197 #ifdef _WIN32
 198 void socket_set_nonblock(int fd)
 199 {
 200     unsigned long opt = 1;
 201     ioctlsocket(fd, FIONBIO, &opt);
 202 }
 203
 204 int inet_aton(const char *cp, struct in_addr *ia)
 205 {
 206     uint32_t addr = inet_addr(cp);
 207     if (addr == 0xffffffff)
 208         return 0;
 209     ia->s_addr = addr;
 210     return 1;
 211 }
 212
 213 void qemu_set_cloexec(int fd)
 214 {
 215 }
 216
 217 #else
 218
 219 void socket_set_nonblock(int fd)
 220 {
 221     int f;
 222     f = fcntl(fd, F_GETFL);
 223     fcntl(fd, F_SETFL, f | O_NONBLOCK);
 224 }
 225
 226 void qemu_set_cloexec(int fd)
 227 {
 228     int f;
 229     f = fcntl(fd, F_GETFD);
 230     fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 231 }
 232
 233 #endif
 234
 235 /*
 236  * Opens a file with FD_CLOEXEC set
 237  */
 238 int qemu_open(const char *name, int flags, ...)
 239 {
 240     int ret;
 241     int mode = 0;
 242
 243     if (flags & O_CREAT) {
 244         va_list ap;
 245
 246         va_start(ap, flags);
 247         mode = va_arg(ap, int);
 248         va_end(ap);
 249     }
 250
 251 #ifdef O_CLOEXEC
 252     ret = open(name, flags | O_CLOEXEC, mode);
 253 #else
 254     ret = open(name, flags, mode);
 255     if (ret >= 0) {
 256         qemu_set_cloexec(ret);
 257     }
 258 #endif
 259
 260     return ret;
 261 }
 262
 263 /*
 264  * A variant of write(2) which handles partial write.
 265  *
 266  * Return the number of bytes transferred.
 267  * Set errno if fewer than `count' bytes are written.
 268  *
 269  * This function don't work with non-blocking fd's.
 270  * Any of the possibilities with non-bloking fd's is bad:
 271  *   - return a short write (then name is wrong)
 272  *   - busy wait adding (errno == EAGAIN) to the loop
 273  */
 274 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 275 {
 276     ssize_t ret = 0;
 277     ssize_t total = 0;
 278
 279     while (count) {
 280         ret = write(fd, buf, count);
 281         if (ret < 0) {
 282             if (errno == EINTR)
 283                 continue;
 284             break;
 285         }
 286
 287         count -= ret;
 288         buf += ret;
 289         total += ret;
 290     }
 291
 292     return total;
 293 }
 294
 295 #ifndef _WIN32
 296 /*
 297  * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
 298  */
 299 int qemu_eventfd(int fds[2])
 300 {
 301 #ifdef CONFIG_EVENTFD
 302     int ret;
 303
 304     ret = eventfd(0, 0);
 305     if (ret >= 0) {
 306         fds[0] = ret;
 307         qemu_set_cloexec(ret);
 308         if ((fds[1] = dup(ret)) == -1) {
 309             close(ret);
 310             return -1;
 311         }
 312         qemu_set_cloexec(fds[1]);
 313         return 0;
 314     }
 315
 316     if (errno != ENOSYS) {
 317         return -1;
 318     }
 319 #endif
 320
 321     return qemu_pipe(fds);
 322 }
 323
 324 /*
 325  * Creates a pipe with FD_CLOEXEC set on both file descriptors
 326  */
 327 int qemu_pipe(int pipefd[2])
 328 {
 329     int ret;
 330
 331 #ifdef CONFIG_PIPE2
 332     ret = pipe2(pipefd, O_CLOEXEC);
 333     if (ret != -1 || errno != ENOSYS) {
 334         return ret;
 335     }
 336 #endif
 337     ret = pipe(pipefd);
 338     if (ret == 0) {
 339         qemu_set_cloexec(pipefd[0]);
 340         qemu_set_cloexec(pipefd[1]);
 341     }
 342
 343     return ret;
 344 }
 345 #endif
 346
 347 /*
 348  * Opens a socket with FD_CLOEXEC set
 349  */
 350 int qemu_socket(int domain, int type, int protocol)
 351 {
 352     int ret;
 353
 354 #ifdef SOCK_CLOEXEC
 355     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 356     if (ret != -1 || errno != EINVAL) {
 357         return ret;
 358     }
 359 #endif
 360     ret = socket(domain, type, protocol);
 361     if (ret >= 0) {
 362         qemu_set_cloexec(ret);
 363     }
 364
 365     return ret;
 366 }
 367
 368 /*
 369  * Accept a connection and set FD_CLOEXEC
 370  */
 371 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 372 {
 373     int ret;
 374
 375 #ifdef CONFIG_ACCEPT4
 376     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 377     if (ret != -1 || errno != ENOSYS) {
 378         return ret;
 379     }
 380 #endif
 381     ret = accept(s, addr, addrlen);
 382     if (ret >= 0) {
 383         qemu_set_cloexec(ret);
 384     }
 385
 386     return ret;
 387 }