File:  [Qemu by Fabrice Bellard] / qemu / oslib-posix.c
Revision 1.1.1.2 (vendor branch): download - view: text, annotated - select for diffs
Tue Apr 24 18:56:33 2018 UTC (3 years, 1 month ago) by root
Branches: qemu, MAIN
CVS tags: qemu1000, qemu0151, HEAD
qemu 0.15.1

    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
   35: extern 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: 
   45: int qemu_daemon(int nochdir, int noclose)
   46: {
   47:     return daemon(nochdir, noclose);
   48: }
   49: 
   50: void *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: 
   59: void *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 */
   80: void *qemu_vmalloc(size_t size)
   81: {
   82:     return qemu_memalign(getpagesize(), size);
   83: }
   84: 
   85: void qemu_vfree(void *ptr)
   86: {
   87:     trace_qemu_vfree(ptr);
   88:     free(ptr);
   89: }
   90: 
   91: void 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: 
   98: void 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:  */
  108: int 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: 
  127: int 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: }

unix.superglobalmegacorp.com