liblttng-ust/wait.h

   1 #ifndef _UST_WAIT_H
   2 #define _UST_WAIT_H
   3
   4 /*
   5  * Copyright (C) 2011  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; version 2.1 of
  10  * the License.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  20  */
  21
  22 #include <poll.h>
  23
  24 /*
  25  * Wait until "cond" gets true or timeout (in ms).
  26  */
  27 #define wait_cond_interruptible_timeout(_cond, _timeout)        \
  28         ({                                                      \
  29                 int __ret = 0, __pollret;                       \
  30                 int __timeout = _timeout;                       \
  31                                                                 \
  32                 for (;;) {                                      \
  33                         if (_cond)                              \
  34                                 break;                          \
  35                         if (__timeout <= 0) {                   \
  36                                 __ret = -ETIMEDOUT;             \
  37                                 break;                          \
  38                         }                                       \
  39                         __pollret = poll(NULL, 0, 10);  /* wait 10ms */ \
  40                         if (__pollret < 0) {                    \
  41                                 __ret = -errno;                 \
  42                                 break;                          \
  43                         }                                       \
  44                         __timeout -= 10;                        \
  45                 }                                               \
  46                 __ret;                                          \
  47         })
  48
  49
  50 #endif /* _UST_WAIT_H */