LXR qemu/oslib-posix.c

   1/*
   2 * os-posix-lib.c
   3 *
   4 * Copyright (c) 2003-2008 Fabrice Bellard
   5 * Copyright (c) 2010 Red Hat, Inc.
   6 *
   7 * QEMU library functions on POSIX which are shared between QEMU and
   8 * the QEMU tools.
   9 *
  10 * Permission is hereby granted, free of charge, to any person obtaining a copy
  11 * of this software and associated documentation files (the "Software"), to deal
  12 * in the Software without restriction, including without limitation the rights
  13 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  14 * copies of the Software, and to permit persons to whom the Software is
  15 * furnished to do so, subject to the following conditions:
  16 *
  17 * The above copyright notice and this permission notice shall be included in
  18 * all copies or substantial portions of the Software.
  19 *
  20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  21 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  22 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  23 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  24 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  26 * THE SOFTWARE.
  27 */
  28
  29/* The following block of code temporarily renames the daemon() function so the
  30   compiler does not see the warning associated with it in stdlib.h on OSX */
  31#ifdef __APPLE__
  32#define daemon qemu_fake_daemon_function
  33#include <stdlib.h>
  34#undef daemon
  35extern int daemon(int, int);
  36#endif
  37
  38#include "config-host.h"
  39#include "sysemu.h"
  40#include "trace.h"
  41#include "qemu_socket.h"
  42
  43
  44
  45int qemu_daemon(int nochdir, int noclose)
  46{
  47    return daemon(nochdir, noclose);
  48}
  49
  50void *qemu_oom_check(void *ptr)
  51{
  52    if (ptr == NULL) {
  53        fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
  54        abort();
  55    }
  56    return ptr;
  57}
  58
  59void *qemu_memalign(size_t alignment, size_t size)
  60{
  61    void *ptr;
  62#if defined(_POSIX_C_SOURCE) && !defined(__sun__)
  63    int ret;
  64    ret = posix_memalign(&ptr, alignment, size);
  65    if (ret != 0) {
  66        fprintf(stderr, "Failed to allocate %zu B: %s\n",
  67                size, strerror(ret));
  68        abort();
  69    }
  70#elif defined(CONFIG_BSD)
  71    ptr = qemu_oom_check(valloc(size));
  72#else
  73    ptr = qemu_oom_check(memalign(alignment, size));
  74#endif
  75    trace_qemu_memalign(alignment, size, ptr);
  76    return ptr;
  77}
  78
  79/* alloc shared memory pages */
  80void *qemu_vmalloc(size_t size)
  81{
  82    return qemu_memalign(getpagesize(), size);
  83}
  84
  85void qemu_vfree(void *ptr)
  86{
  87    trace_qemu_vfree(ptr);
  88    free(ptr);
  89}
  90
  91void socket_set_nonblock(int fd)
  92{
  93    int f;
  94    f = fcntl(fd, F_GETFL);
  95    fcntl(fd, F_SETFL, f | O_NONBLOCK);
  96}
  97
  98void qemu_set_cloexec(int fd)
  99{
 100    int f;
 101    f = fcntl(fd, F_GETFD);
 102    fcntl(fd, F_SETFD, f | FD_CLOEXEC);
 103}
 104
 105/*
 106 * Creates a pipe with FD_CLOEXEC set on both file descriptors
 107 */
 108int qemu_pipe(int pipefd[2])
 109{
 110    int ret;
 111
 112#ifdef CONFIG_PIPE2
 113    ret = pipe2(pipefd, O_CLOEXEC);
 114    if (ret != -1 || errno != ENOSYS) {
 115        return ret;
 116    }
 117#endif
 118    ret = pipe(pipefd);
 119    if (ret == 0) {
 120        qemu_set_cloexec(pipefd[0]);
 121        qemu_set_cloexec(pipefd[1]);
 122    }
 123
 124    return ret;
 125}
 126
 127int qemu_utimensat(int dirfd, const char *path, const struct timespec *times,
 128                   int flags)
 129{
 130    struct timeval tv[2], tv_now;
 131    struct stat st;
 132    int i;
 133#ifdef CONFIG_UTIMENSAT
 134    int ret;
 135
 136    ret = utimensat(dirfd, path, times, flags);
 137    if (ret != -1 || errno != ENOSYS) {
 138        return ret;
 139    }
 140#endif
 141    /* Fallback: use utimes() instead of utimensat() */
 142
 143    /* happy if special cases */
 144    if (times[0].tv_nsec == UTIME_OMIT && times[1].tv_nsec == UTIME_OMIT) {
 145        return 0;
 146    }
 147    if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW) {
 148        return utimes(path, NULL);
 149    }
 150
 151    /* prepare for hard cases */
 152    if (times[0].tv_nsec == UTIME_NOW || times[1].tv_nsec == UTIME_NOW) {
 153        gettimeofday(&tv_now, NULL);
 154    }
 155    if (times[0].tv_nsec == UTIME_OMIT || times[1].tv_nsec == UTIME_OMIT) {
 156        stat(path, &st);
 157    }
 158
 159    for (i = 0; i < 2; i++) {
 160        if (times[i].tv_nsec == UTIME_NOW) {
 161            tv[i].tv_sec = tv_now.tv_sec;
 162            tv[i].tv_usec = tv_now.tv_usec;
 163        } else if (times[i].tv_nsec == UTIME_OMIT) {
 164            tv[i].tv_sec = (i == 0) ? st.st_atime : st.st_mtime;
 165            tv[i].tv_usec = 0;
 166        } else {
 167            tv[i].tv_sec = times[i].tv_sec;
 168            tv[i].tv_usec = times[i].tv_nsec / 1000;
 169        }
 170    }
 171
 172    return utimes(path, &tv[0]);
 173}
 174