/*
  This file is part of the Astrometry.net suite.
  Copyright 2008, 2010 Dustin Lang.

  The Astrometry.net suite is free software; you can redistribute
  it and/or modify it under the terms of the GNU General Public License
  as published by the Free Software Foundation, version 2.

  The Astrometry.net suite is distributed in the hope that it will be
  useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with the Astrometry.net suite ; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
*/
#ifndef OS_FEATURES_H
#define OS_FEATURES_H

#include "os-features-config.h"

// Features we use that aren't standard across all supported platforms

char* canonicalize_file_name(const char* fn);

// This is actually in POSIX1b but may or may not be available.
int fdatasync(int fd);

/**
   The qsort_r story:

   -qsort_r appears in BSD (including Mac OSX)
   -qsort_r appears in glibc 2.8, but with a different argument order.

   We check a few things:
   -is qsort_r declared?
   -does qsort_r exist?
   -do we need to swap the arguments?

   Those using qsort_r in Astrometry.net should instead use the macro QSORT_R()
   to take advantage of these tests.

   QSORT_R(void* base, size_t nmembers, size_t member_size, void* token,
           comparison_function);

   You should define the "comparison" function like this:

   static int QSORT_COMPARISON_FUNCTION(my_comparison, void* token, const void* v1, const void* v2) {
     ...
   }


   Distributions including glibc 2.8 include:
   -Mandriva 2009
   -Ubuntu 8.10
*/

#if NEED_DECLARE_QSORT_R
//// NOTE: this declaration must match os-features-test.c .
void qsort_r(void *base, size_t nmemb, size_t sz,
             void *userdata,
             int (*compar)(void *, const void *, const void *));
#endif

#if NEED_SWAP_QSORT_R
#define QSORT_R(a,b,c,d,e) qsort_r(a,b,c,e,d)
#define QSORT_COMPARISON_FUNCTION(func, thunk, v1, v2) func(v1, v2, thunk)

#else
#define QSORT_R qsort_r
#define QSORT_COMPARISON_FUNCTION(func, thunk, v1, v2) func(thunk, v1, v2)

#endif

// As suggested in http://gcc.gnu.org/onlinedocs/gcc-4.3.0/gcc/Function-Names.html
#if __STDC_VERSION__ < 199901L
# if __GNUC__ >= 2
#  define __func__ __FUNCTION__
# else
#  define __func__ "<unknown>"
# endif
#endif

#endif
