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 #if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)
  36 #include <sys/mman.h>
  37 #endif
  38
  39 #ifdef CONFIG_SOLARIS
  40 #include <sys/types.h>
  41 #include <sys/statvfs.h>
  42 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for
  43    discussion about Solaris header problems */
  44 extern int madvise(caddr_t, size_t, int);
  45 #endif
  46
  47 #ifdef CONFIG_EVENTFD
  48 #include <sys/eventfd.h>
  49 #endif
  50
  51 #ifdef _WIN32
  52 #include <windows.h>
  53 #elif defined(CONFIG_BSD)
  54 #include <stdlib.h>
  55 #else
  56 #include <malloc.h>
  57 #endif
  58
  59 #include "qemu-common.h"
  60 #include "trace.h"
  61 #include "sysemu.h"
  62 #include "qemu_socket.h"
  63
  64 #if !defined(_POSIX_C_SOURCE) || defined(_WIN32) || defined(__sun__)
  65 static void *oom_check(void *ptr)
  66 {
  67     if (ptr == NULL) {
  68 #if defined(_WIN32)
  69         fprintf(stderr, "Failed to allocate memory: %lu\n", GetLastError());
  70 #else
  71         fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
  72 #endif
  73         abort();
  74     }
  75     return ptr;
  76 }
  77 #endif
  78
  79 #if defined(_WIN32)
  80 void *qemu_memalign(size_t alignment, size_t size)
  81 {
  82     void *ptr;
  83
  84     if (!size) {
  85         abort();
  86     }
  87     ptr = oom_check(VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE));
  88     trace_qemu_memalign(alignment, size, ptr);
  89     return ptr;
  90 }
  91
  92 void *qemu_vmalloc(size_t size)
  93 {
  94     void *ptr;
  95
  96     /* FIXME: this is not exactly optimal solution since VirtualAlloc
  97        has 64Kb granularity, but at least it guarantees us that the
  98        memory is page aligned. */
  99     if (!size) {
 100         abort();
 101     }
 102     ptr = oom_check(VirtualAlloc(NULL, size, MEM_COMMIT, PAGE_READWRITE));
 103     trace_qemu_vmalloc(size, ptr);
 104     return ptr;
 105 }
 106
 107 void qemu_vfree(void *ptr)
 108 {
 109     trace_qemu_vfree(ptr);
 110     VirtualFree(ptr, 0, MEM_RELEASE);
 111 }
 112
 113 #else
 114
 115 void *qemu_memalign(size_t alignment, size_t size)
 116 {
 117     void *ptr;
 118 #if defined(_POSIX_C_SOURCE) && !defined(__sun__)
 119     int ret;
 120     ret = posix_memalign(&ptr, alignment, size);
 121     if (ret != 0) {
 122         fprintf(stderr, "Failed to allocate %zu B: %s\n",
 123                 size, strerror(ret));
 124         abort();
 125     }
 126 #elif defined(CONFIG_BSD)
 127     ptr = oom_check(valloc(size));
 128 #else
 129     ptr = oom_check(memalign(alignment, size));
 130 #endif
 131     trace_qemu_memalign(alignment, size, ptr);
 132     return ptr;
 133 }
 134
 135 /* alloc shared memory pages */
 136 void *qemu_vmalloc(size_t size)
 137 {
 138 #ifndef __ia64__
 139     return qemu_memalign(getpagesize(), size);
 140 #else
 141     return qemu_memalign(65536, size);
 142 #endif
 143 }
 144
 145 void qemu_vfree(void *ptr)
 146 {
 147     trace_qemu_vfree(ptr);
 148     free(ptr);
 149 }
 150
 151 #endif
 152
 153 int qemu_madvise(void *addr, size_t len, int advice)
 154 {
 155     if (advice == QEMU_MADV_INVALID) {
 156         errno = EINVAL;
 157         return -1;
 158     }
 159 #if defined(CONFIG_MADVISE)
 160     return madvise(addr, len, advice);
 161 #elif defined(CONFIG_POSIX_MADVISE)
 162     return posix_madvise(addr, len, advice);
 163 #else
 164     errno = EINVAL;
 165     return -1;
 166 #endif
 167 }
 168
 169 int qemu_create_pidfile(const char *filename)
 170 {
 171     char buffer[128];
 172     int len;
 173 #ifndef _WIN32
 174     int fd;
 175
 176     fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
 177     if (fd == -1)
 178         return -1;
 179
 180     if (lockf(fd, F_TLOCK, 0) == -1)
 181         return -1;
 182
 183     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 184     if (write(fd, buffer, len) != len)
 185         return -1;
 186 #else
 187     HANDLE file;
 188     OVERLAPPED overlap;
 189     BOOL ret;
 190     memset(&overlap, 0, sizeof(overlap));
 191
 192     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
 193                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 194
 195     if (file == INVALID_HANDLE_VALUE)
 196       return -1;
 197
 198     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 199     ret = WriteFileEx(file, (LPCVOID)buffer, (DWORD)len,
 200                       &overlap, NULL);
 201     if (ret == 0)
 202       return -1;
 203 #endif
 204     return 0;
 205 }
 206
 207 #ifdef _WIN32
 208
 209 /* mingw32 needs ffs for compilations without optimization. */
 210 int ffs(int i)
 211 {
 212     /* Use gcc's builtin ffs. */
 213     return __builtin_ffs(i);
 214 }
 215
 216 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 217 #define _W32_FT_OFFSET (116444736000000000ULL)
 218
 219 int qemu_gettimeofday(qemu_timeval *tp)
 220 {
 221   union {
 222     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 223     FILETIME ft;
 224   }  _now;
 225
 226   if(tp)
 227     {
 228       GetSystemTimeAsFileTime (&_now.ft);
 229       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 230       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 231     }
 232   /* Always return 0 as per Open Group Base Specifications Issue 6.
 233      Do not set errno on error.  */
 234   return 0;
 235 }
 236 #endif /* _WIN32 */
 237
 238
 239 #ifdef _WIN32
 240 void socket_set_nonblock(int fd)
 241 {
 242     unsigned long opt = 1;
 243     ioctlsocket(fd, FIONBIO, &opt);
 244 }
 245
 246 int inet_aton(const char *cp, struct in_addr *ia)
 247 {
 248     uint32_t addr = inet_addr(cp);
 249     if (addr == 0xffffffff)
 250         return 0;
 251     ia->s_addr = addr;
 252     return 1;
 253 }
 254
 255 void qemu_set_cloexec(int fd)
 256 {
 257 }
 258
 259 #else
 260
 261 void socket_set_nonblock(int fd)
 262 {
 263     int f;
 264     f = fcntl(fd, F_GETFL);
 265     fcntl(fd, F_SETFL, f | O_NONBLOCK);
 266 }
 267
 268 void qemu_set_cloexec(int fd)
 269 {
 270     int f;
 271     f = fcntl(fd, F_GETFD);
 272     fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 273 }
 274
 275 #endif
 276
 277 /*
 278  * Opens a file with FD_CLOEXEC set
 279  */
 280 int qemu_open(const char *name, int flags, ...)
 281 {
 282     int ret;
 283     int mode = 0;
 284
 285     if (flags & O_CREAT) {
 286         va_list ap;
 287
 288         va_start(ap, flags);
 289         mode = va_arg(ap, int);
 290         va_end(ap);
 291     }
 292
 293 #ifdef O_CLOEXEC
 294     ret = open(name, flags | O_CLOEXEC, mode);
 295 #else
 296     ret = open(name, flags, mode);
 297     if (ret >= 0) {
 298         qemu_set_cloexec(ret);
 299     }
 300 #endif
 301
 302     return ret;
 303 }
 304
 305 /*
 306  * A variant of write(2) which handles partial write.
 307  *
 308  * Return the number of bytes transferred.
 309  * Set errno if fewer than `count' bytes are written.
 310  *
 311  * This function don't work with non-blocking fd's.
 312  * Any of the possibilities with non-bloking fd's is bad:
 313  *   - return a short write (then name is wrong)
 314  *   - busy wait adding (errno == EAGAIN) to the loop
 315  */
 316 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 317 {
 318     ssize_t ret = 0;
 319     ssize_t total = 0;
 320
 321     while (count) {
 322         ret = write(fd, buf, count);
 323         if (ret < 0) {
 324             if (errno == EINTR)
 325                 continue;
 326             break;
 327         }
 328
 329         count -= ret;
 330         buf += ret;
 331         total += ret;
 332     }
 333
 334     return total;
 335 }
 336
 337 #ifndef _WIN32
 338 /*
 339  * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
 340  */
 341 int qemu_eventfd(int fds[2])
 342 {
 343 #ifdef CONFIG_EVENTFD
 344     int ret;
 345
 346     ret = eventfd(0, 0);
 347     if (ret >= 0) {
 348         fds[0] = ret;
 349         qemu_set_cloexec(ret);
 350         if ((fds[1] = dup(ret)) == -1) {
 351             close(ret);
 352             return -1;
 353         }
 354         qemu_set_cloexec(fds[1]);
 355         return 0;
 356     }
 357
 358     if (errno != ENOSYS) {
 359         return -1;
 360     }
 361 #endif
 362
 363     return qemu_pipe(fds);
 364 }
 365
 366 /*
 367  * Creates a pipe with FD_CLOEXEC set on both file descriptors
 368  */
 369 int qemu_pipe(int pipefd[2])
 370 {
 371     int ret;
 372
 373 #ifdef CONFIG_PIPE2
 374     ret = pipe2(pipefd, O_CLOEXEC);
 375     if (ret != -1 || errno != ENOSYS) {
 376         return ret;
 377     }
 378 #endif
 379     ret = pipe(pipefd);
 380     if (ret == 0) {
 381         qemu_set_cloexec(pipefd[0]);
 382         qemu_set_cloexec(pipefd[1]);
 383     }
 384
 385     return ret;
 386 }
 387 #endif
 388
 389 /*
 390  * Opens a socket with FD_CLOEXEC set
 391  */
 392 int qemu_socket(int domain, int type, int protocol)
 393 {
 394     int ret;
 395
 396 #ifdef SOCK_CLOEXEC
 397     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 398     if (ret != -1 || errno != EINVAL) {
 399         return ret;
 400     }
 401 #endif
 402     ret = socket(domain, type, protocol);
 403     if (ret >= 0) {
 404         qemu_set_cloexec(ret);
 405     }
 406
 407     return ret;
 408 }
 409
 410 /*
 411  * Accept a connection and set FD_CLOEXEC
 412  */
 413 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 414 {
 415     int ret;
 416
 417 #ifdef CONFIG_ACCEPT4
 418     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 419     if (ret != -1 || errno != ENOSYS) {
 420         return ret;
 421     }
 422 #endif
 423     ret = accept(s, addr, addrlen);
 424     if (ret >= 0) {
 425         qemu_set_cloexec(ret);
 426     }
 427
 428     return ret;
 429 }