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     return qemu_memalign(getpagesize(), size);
 139 }
 140
 141 void qemu_vfree(void *ptr)
 142 {
 143     trace_qemu_vfree(ptr);
 144     free(ptr);
 145 }
 146
 147 #endif
 148
 149 int qemu_madvise(void *addr, size_t len, int advice)
 150 {
 151     if (advice == QEMU_MADV_INVALID) {
 152         errno = EINVAL;
 153         return -1;
 154     }
 155 #if defined(CONFIG_MADVISE)
 156     return madvise(addr, len, advice);
 157 #elif defined(CONFIG_POSIX_MADVISE)
 158     return posix_madvise(addr, len, advice);
 159 #else
 160     errno = EINVAL;
 161     return -1;
 162 #endif
 163 }
 164
 165 int qemu_create_pidfile(const char *filename)
 166 {
 167     char buffer[128];
 168     int len;
 169 #ifndef _WIN32
 170     int fd;
 171
 172     fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
 173     if (fd == -1)
 174         return -1;
 175
 176     if (lockf(fd, F_TLOCK, 0) == -1)
 177         return -1;
 178
 179     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 180     if (write(fd, buffer, len) != len)
 181         return -1;
 182 #else
 183     HANDLE file;
 184     OVERLAPPED overlap;
 185     BOOL ret;
 186     memset(&overlap, 0, sizeof(overlap));
 187
 188     file = CreateFile(filename, GENERIC_WRITE, FILE_SHARE_READ, NULL,
 189                       OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
 190
 191     if (file == INVALID_HANDLE_VALUE)
 192       return -1;
 193
 194     len = snprintf(buffer, sizeof(buffer), "%ld\n", (long)getpid());
 195     ret = WriteFileEx(file, (LPCVOID)buffer, (DWORD)len,
 196                       &overlap, NULL);
 197     if (ret == 0)
 198       return -1;
 199 #endif
 200     return 0;
 201 }
 202
 203 #ifdef _WIN32
 204
 205 /* mingw32 needs ffs for compilations without optimization. */
 206 int ffs(int i)
 207 {
 208     /* Use gcc's builtin ffs. */
 209     return __builtin_ffs(i);
 210 }
 211
 212 /* Offset between 1/1/1601 and 1/1/1970 in 100 nanosec units */
 213 #define _W32_FT_OFFSET (116444736000000000ULL)
 214
 215 int qemu_gettimeofday(qemu_timeval *tp)
 216 {
 217   union {
 218     unsigned long long ns100; /*time since 1 Jan 1601 in 100ns units */
 219     FILETIME ft;
 220   }  _now;
 221
 222   if(tp)
 223     {
 224       GetSystemTimeAsFileTime (&_now.ft);
 225       tp->tv_usec=(long)((_now.ns100 / 10ULL) % 1000000ULL );
 226       tp->tv_sec= (long)((_now.ns100 - _W32_FT_OFFSET) / 10000000ULL);
 227     }
 228   /* Always return 0 as per Open Group Base Specifications Issue 6.
 229      Do not set errno on error.  */
 230   return 0;
 231 }
 232 #endif /* _WIN32 */
 233
 234
 235 #ifdef _WIN32
 236 void socket_set_nonblock(int fd)
 237 {
 238     unsigned long opt = 1;
 239     ioctlsocket(fd, FIONBIO, &opt);
 240 }
 241
 242 int inet_aton(const char *cp, struct in_addr *ia)
 243 {
 244     uint32_t addr = inet_addr(cp);
 245     if (addr == 0xffffffff)
 246         return 0;
 247     ia->s_addr = addr;
 248     return 1;
 249 }
 250
 251 void qemu_set_cloexec(int fd)
 252 {
 253 }
 254
 255 #else
 256
 257 void socket_set_nonblock(int fd)
 258 {
 259     int f;
 260     f = fcntl(fd, F_GETFL);
 261     fcntl(fd, F_SETFL, f | O_NONBLOCK);
 262 }
 263
 264 void qemu_set_cloexec(int fd)
 265 {
 266     int f;
 267     f = fcntl(fd, F_GETFD);
 268     fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 269 }
 270
 271 #endif
 272
 273 /*
 274  * Opens a file with FD_CLOEXEC set
 275  */
 276 int qemu_open(const char *name, int flags, ...)
 277 {
 278     int ret;
 279     int mode = 0;
 280
 281     if (flags & O_CREAT) {
 282         va_list ap;
 283
 284         va_start(ap, flags);
 285         mode = va_arg(ap, int);
 286         va_end(ap);
 287     }
 288
 289 #ifdef O_CLOEXEC
 290     ret = open(name, flags | O_CLOEXEC, mode);
 291 #else
 292     ret = open(name, flags, mode);
 293     if (ret >= 0) {
 294         qemu_set_cloexec(ret);
 295     }
 296 #endif
 297
 298     return ret;
 299 }
 300
 301 /*
 302  * A variant of write(2) which handles partial write.
 303  *
 304  * Return the number of bytes transferred.
 305  * Set errno if fewer than `count' bytes are written.
 306  *
 307  * This function don't work with non-blocking fd's.
 308  * Any of the possibilities with non-bloking fd's is bad:
 309  *   - return a short write (then name is wrong)
 310  *   - busy wait adding (errno == EAGAIN) to the loop
 311  */
 312 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 313 {
 314     ssize_t ret = 0;
 315     ssize_t total = 0;
 316
 317     while (count) {
 318         ret = write(fd, buf, count);
 319         if (ret < 0) {
 320             if (errno == EINTR)
 321                 continue;
 322             break;
 323         }
 324
 325         count -= ret;
 326         buf += ret;
 327         total += ret;
 328     }
 329
 330     return total;
 331 }
 332
 333 #ifndef _WIN32
 334 /*
 335  * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
 336  */
 337 int qemu_eventfd(int fds[2])
 338 {
 339 #ifdef CONFIG_EVENTFD
 340     int ret;
 341
 342     ret = eventfd(0, 0);
 343     if (ret >= 0) {
 344         fds[0] = ret;
 345         qemu_set_cloexec(ret);
 346         if ((fds[1] = dup(ret)) == -1) {
 347             close(ret);
 348             return -1;
 349         }
 350         qemu_set_cloexec(fds[1]);
 351         return 0;
 352     }
 353
 354     if (errno != ENOSYS) {
 355         return -1;
 356     }
 357 #endif
 358
 359     return qemu_pipe(fds);
 360 }
 361
 362 /*
 363  * Creates a pipe with FD_CLOEXEC set on both file descriptors
 364  */
 365 int qemu_pipe(int pipefd[2])
 366 {
 367     int ret;
 368
 369 #ifdef CONFIG_PIPE2
 370     ret = pipe2(pipefd, O_CLOEXEC);
 371     if (ret != -1 || errno != ENOSYS) {
 372         return ret;
 373     }
 374 #endif
 375     ret = pipe(pipefd);
 376     if (ret == 0) {
 377         qemu_set_cloexec(pipefd[0]);
 378         qemu_set_cloexec(pipefd[1]);
 379     }
 380
 381     return ret;
 382 }
 383 #endif
 384
 385 /*
 386  * Opens a socket with FD_CLOEXEC set
 387  */
 388 int qemu_socket(int domain, int type, int protocol)
 389 {
 390     int ret;
 391
 392 #ifdef SOCK_CLOEXEC
 393     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 394     if (ret != -1 || errno != EINVAL) {
 395         return ret;
 396     }
 397 #endif
 398     ret = socket(domain, type, protocol);
 399     if (ret >= 0) {
 400         qemu_set_cloexec(ret);
 401     }
 402
 403     return ret;
 404 }
 405
 406 /*
 407  * Accept a connection and set FD_CLOEXEC
 408  */
 409 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 410 {
 411     int ret;
 412
 413 #ifdef CONFIG_ACCEPT4
 414     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 415     if (ret != -1 || errno != ENOSYS) {
 416         return ret;
 417     }
 418 #endif
 419     ret = accept(s, addr, addrlen);
 420     if (ret >= 0) {
 421         qemu_set_cloexec(ret);
 422     }
 423
 424     return ret;
 425 }