m4/qsort_r.m4

   1 # qsort_r.m4
   2 # serial 1
   3 dnl Copyright 2014-2024 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 Reentrant sort function.
   9
  10 dnl Written by Paul Eggert.
  11
  12 AC_DEFUN([gl_FUNC_QSORT_R],
  13 [
  14   dnl Persuade glibc to declare qsort_r.
  15   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
  16
  17   AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
  18
  19   AC_CHECK_FUNCS_ONCE([qsort_r])
  20   if test $ac_cv_func_qsort_r = yes; then
  21     AC_CACHE_CHECK([for qsort_r signature], [gl_cv_qsort_r_signature],
  22       [AC_LINK_IFELSE(
  23          [AC_LANG_PROGRAM([[#include <stdlib.h>
  24                             void qsort_r (void *, size_t, size_t,
  25                                           int (*) (void const *, void const *,
  26                                                    void *),
  27                                           void *);
  28                             void (*p) (void *, size_t, size_t,
  29                                        int (*) (void const *, void const *,
  30                                                 void *),
  31                                        void *) = qsort_r;
  32                           ]])],
  33          [gl_cv_qsort_r_signature=GNU],
  34          [AC_LINK_IFELSE(
  35             [AC_LANG_PROGRAM([[#include <stdlib.h>
  36                                void qsort_r (void *, size_t, size_t, void *,
  37                                              int (*) (void *,
  38                                                       void const *,
  39                                                       void const *));
  40                                void (*p) (void *, size_t, size_t, void *,
  41                                           int (*) (void *, void const *,
  42                                                    void const *)) = qsort_r;
  43                              ]])],
  44             [gl_cv_qsort_r_signature=BSD],
  45             [gl_cv_qsort_r_signature=unknown])])])
  46     case $gl_cv_qsort_r_signature in
  47       GNU)     ;;
  48       BSD)     REPLACE_QSORT_R=1 ;;
  49       unknown) HAVE_QSORT_R=0 REPLACE_QSORT_R=1 ;;
  50     esac
  51   else
  52     HAVE_QSORT_R=0
  53   fi
  54 ])