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#include "config-host.h"
  30#include "sysemu.h"
  31#include "trace.h"
  32#include "qemu_socket.h"
  33
  34void *qemu_oom_check(void *ptr)
  35{
  36    if (ptr == NULL) {
  37        fprintf(stderr, "Failed to allocate memory: %s\n", strerror(errno));
  38        abort();
  39    }
  40    return ptr;
  41}
  42
  43void *qemu_memalign(size_t alignment, size_t size)
  44{
  45    void *ptr;
  46#if defined(_POSIX_C_SOURCE) && !defined(__sun__)
  47    int ret;
  48    ret = posix_memalign(&ptr, alignment, size);
  49    if (ret != 0) {
  50        fprintf(stderr, "Failed to allocate %zu B: %s\n",
  51                size, strerror(ret));
  52        abort();
  53    }
  54#elif defined(CONFIG_BSD)
  55    ptr = qemu_oom_check(valloc(size));
  56#else
  57    ptr = qemu_oom_check(memalign(alignment, size));
  58#endif
  59    trace_qemu_memalign(alignment, size, ptr);
  60    return ptr;
  61}
  62
  63/* alloc shared memory pages */
  64void *qemu_vmalloc(size_t size)
  65{
  66    return qemu_memalign(getpagesize(), size);
  67}
  68
  69void qemu_vfree(void *ptr)
  70{
  71    trace_qemu_vfree(ptr);
  72    free(ptr);
  73}
  74
  75void socket_set_nonblock(int fd)
  76{
  77    int f;
  78    f = fcntl(fd, F_GETFL);
  79    fcntl(fd, F_SETFL, f | O_NONBLOCK);
  80}
  81
  82void qemu_set_cloexec(int fd)
  83{
  84    int f;
  85    f = fcntl(fd, F_GETFD);
  86    fcntl(fd, F_SETFD, f | FD_CLOEXEC);
  87}
  88
  89/*
  90 * Creates a pipe with FD_CLOEXEC set on both file descriptors
  91 */
  92int qemu_pipe(int pipefd[2])
  93{
  94    int ret;
  95
  96#ifdef CONFIG_PIPE2
  97    ret = pipe2(pipefd, O_CLOEXEC);
  98    if (ret != -1 || errno != ENOSYS) {
  99        return ret;
 100    }
 101#endif
 102    ret = pipe(pipefd);
 103    if (ret == 0) {
 104        qemu_set_cloexec(pipefd[0]);
 105        qemu_set_cloexec(pipefd[1]);
 106    }
 107
 108    return ret;
 109}
 110
 111int qemu_utimensat(int dirfd, const char *path, const struct timespec *times,
 112                   int flags)
 113{
 114    struct timeval tv[2], tv_now;
 115    struct stat st;
 116    int i;
 117#ifdef CONFIG_UTIMENSAT
 118    int ret;
 119
 120    ret = utimensat(dirfd, path, times, flags);
 121    if (ret != -1 || errno != ENOSYS) {
 122        return ret;
 123    }
 124#endif
 125    /* Fallback: use utimes() instead of utimensat() */
 126
 127    /* happy if special cases */
 128    if (times[0].tv_nsec == UTIME_OMIT && times[1].tv_nsec == UTIME_OMIT) {
 129        return 0;
 130    }
 131    if (times[0].tv_nsec == UTIME_NOW && times[1].tv_nsec == UTIME_NOW) {
 132        return utimes(path, NULL);
 133    }
 134
 135    /* prepare for hard cases */
 136    if (times[0].tv_nsec == UTIME_NOW || times[1].tv_nsec == UTIME_NOW) {
 137        gettimeofday(&tv_now, NULL);
 138    }
 139    if (times[0].tv_nsec == UTIME_OMIT || times[1].tv_nsec == UTIME_OMIT) {
 140        stat(path, &st);
 141    }
 142
 143    for (i = 0; i < 2; i++) {
 144        if (times[i].tv_nsec == UTIME_NOW) {
 145            tv[i].tv_sec = tv_now.tv_sec;
 146            tv[i].tv_usec = tv_now.tv_usec;
 147        } else if (times[i].tv_nsec == UTIME_OMIT) {
 148            tv[i].tv_sec = (i == 0) ? st.st_atime : st.st_mtime;
 149            tv[i].tv_usec = 0;
 150        } else {
 151            tv[i].tv_sec = times[i].tv_sec;
 152            tv[i].tv_usec = times[i].tv_nsec / 1000;
 153        }
 154    }
 155
 156    return utimes(path, &tv[0]);
 157}
 158