xapian-core/common/safeunistd.h

   1 /** @file safeunistd.h
   2  * @brief <unistd.h>, but with compat. and large file support for MSVC.
   3  */
   4 /* Copyright (C) 2007,2015 Olly Betts
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 2 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301
  19  * USA
  20  */
  21
  22 #ifndef XAPIAN_INCLUDED_SAFEUNISTD_H
  23 #define XAPIAN_INCLUDED_SAFEUNISTD_H
  24
  25 #ifndef _MSC_VER
  26 # include <unistd.h>
  27 #else
  28
  29 // io.h is the nearest equivalent to unistd.h.
  30 # include <io.h>
  31
  32 // process.h is needed for getpid().
  33 # include <process.h>
  34
  35 // direct.h is needed for rmdir().
  36 # include <direct.h>
  37
  38 #endif
  39
  40 // Under mingw we probably don't need to provide our own sleep().
  41 #if defined __WIN32__ && !defined HAVE_SLEEP
  42
  43 inline unsigned int
  44 sleep(unsigned int seconds)
  45 {
  46     // Use our own little helper function to avoid pulling in <windows.h>.
  47     extern void xapian_sleep_milliseconds(unsigned int millisecs);
  48
  49     // Sleep takes a time interval in milliseconds, whereas POSIX sleep takes
  50     // a time interval in seconds, so we need to multiply 'seconds' by 1000.
  51     //
  52     // But make sure the multiplication won't overflow!  4294967 seconds is
  53     // nearly 50 days, so just sleep for that long and return the number of
  54     // seconds left to sleep for.  The common case of sleep(CONSTANT) should
  55     // optimise to just xapian_sleep_milliseconds(CONSTANT).
  56     if (seconds > 4294967u) {
  57         xapian_sleep_milliseconds(4294967000u);
  58         return seconds - 4294967u;
  59     }
  60     xapian_sleep_milliseconds(seconds * 1000u);
  61     return 0;
  62 }
  63
  64 #endif
  65
  66 #endif /* XAPIAN_INCLUDED_SAFEUNISTD_H */