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