libs/pbd/pbd/timersub.h

   1 /* Copyright (C) 1991-1994,1996-2003,2005,2006,2009
   2         Free Software Foundation, Inc.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <sys/time.h>
  20
  21 #ifndef timersub
  22 # define timersub(a, b, result)                                               \
  23   do {                                                                        \
  24     (result)->tv_sec = (a)->tv_sec - (b)->tv_sec;                             \
  25     (result)->tv_usec = (a)->tv_usec - (b)->tv_usec;                          \
  26     if ((result)->tv_usec < 0) {                                              \
  27       --(result)->tv_sec;                                                     \
  28       (result)->tv_usec += 1000000;                                           \
  29     }                                                                         \
  30   } while (0)
  31 #endif
  32