m4/qsort_r.m4

   1 dnl Reentrant sort function.
   2
   3 dnl Copyright 2014-2017 Free Software Foundation, Inc.
   4 dnl This file is free software; the Free Software Foundation
   5 dnl gives unlimited permission to copy and/or distribute it,
   6 dnl with or without modifications, as long as this notice is preserved.
   7
   8 dnl Written by Paul Eggert.
   9
  10 AC_DEFUN([gl_FUNC_QSORT_R],
  11 [
  12   dnl Persuade glibc to declare qsort_r.
  13   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
  14
  15   AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
  16
  17   AC_CHECK_FUNCS_ONCE([qsort_r])
  18   if test $ac_cv_func_qsort_r = yes; then
  19     AC_CACHE_CHECK([for qsort_r signature], [gl_cv_qsort_r_signature],
  20       [AC_LINK_IFELSE(
  21          [AC_LANG_PROGRAM([[#include <stdlib.h>
  22                             void qsort_r (void *, size_t, size_t,
  23                                           int (*) (void const *, void const *,
  24                                                    void *),
  25                                           void *);
  26                             void (*p) (void *, size_t, size_t,
  27                                        int (*) (void const *, void const *,
  28                                                 void *),
  29                                        void *) = qsort_r;
  30                           ]])],
  31          [gl_cv_qsort_r_signature=GNU],
  32          [AC_LINK_IFELSE(
  33             [AC_LANG_PROGRAM([[#include <stdlib.h>
  34                                void qsort_r (void *, size_t, size_t, void *,
  35                                              int (*) (void *,
  36                                                       void const *,
  37                                                       void const *));
  38                                void (*p) (void *, size_t, size_t, void *,
  39                                           int (*) (void *, void const *,
  40                                                    void const *)) = qsort_r;
  41                              ]])],
  42             [gl_cv_qsort_r_signature=BSD],
  43             [gl_cv_qsort_r_signature=unknown])])])
  44     case $gl_cv_qsort_r_signature in
  45       GNU)     ;;
  46       BSD)     REPLACE_QSORT_R=1 ;;
  47       unknown) HAVE_QSORT_R=0 REPLACE_QSORT_R=1 ;;
  48     esac
  49   else
  50     HAVE_QSORT_R=0
  51   fi
  52 ])