functions.m4

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#   else /* no EXEC_PAGESIZE */
#    ifdef NBPG
#     define getpagesize() NBPG * CLSIZE
#     ifndef CLSIZE
#      define CLSIZE 1
#     endif /* no CLSIZE */
#    else /* no NBPG */
#     ifdef NBPC
#      define getpagesize() NBPC
#     else /* no NBPC */
#      ifdef PAGESIZE
#       define getpagesize() PAGESIZE
#      endif /* PAGESIZE */
#     endif /* no NBPC */
#    endif /* no NBPG */
#   endif /* no EXEC_PAGESIZE */
#  else /* no HAVE_SYS_PARAM_H */
#   define getpagesize() 8192	/* punt totally */
#  endif /* no HAVE_SYS_PARAM_H */
# endif /* no _SC_PAGESIZE */

#endif /* no HAVE_GETPAGESIZE */

int
main ()
{
  char *data, *data2, *data3;
  int i, pagesize;
  int fd;

  pagesize = getpagesize ();

  /* First, make a file with some known garbage in it. */
  data = (char *) malloc (pagesize);
  if (!data)
    return 1;
  for (i = 0; i < pagesize; ++i)
    *(data + i) = rand ();
  umask (0);
  fd = creat ("conftest.mmap", 0600);
  if (fd < 0)
    return 1;
  if (write (fd, data, pagesize) != pagesize)
    return 1;
  close (fd);

  /* Next, try to mmap the file at a fixed address which already has
     something else allocated at it.  If we can, also make sure that
     we see the same garbage.  */
  fd = open ("conftest.mmap", O_RDWR);
  if (fd < 0)
    return 1;
  data2 = (char *) malloc (2 * pagesize);
  if (!data2)
    return 1;
  data2 += (pagesize - ((long int) data2 & (pagesize - 1))) & (pagesize - 1);
  if (data2 != mmap (data2, pagesize, PROT_READ | PROT_WRITE,
		     MAP_PRIVATE | MAP_FIXED, fd, 0L))
    return 1;
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data2 + i))
      return 1;

  /* Finally, make sure that changes to the mapped area do not
     percolate back to the file as seen by read().  (This is a bug on
     some variants of i386 svr4.0.)  */
  for (i = 0; i < pagesize; ++i)
    *(data2 + i) = *(data2 + i) + 1;
  data3 = (char *) malloc (pagesize);
  if (!data3)
    return 1;
  if (read (fd, data3, pagesize) != pagesize)
    return 1;
  for (i = 0; i < pagesize; ++i)
    if (*(data + i) != *(data3 + i))
      return 1;
  close (fd);
  return 0;
}]])],
	       [ac_cv_func_mmap_fixed_mapped=yes],
	       [ac_cv_func_mmap_fixed_mapped=no],
	       [ac_cv_func_mmap_fixed_mapped=no])])
if test $ac_cv_func_mmap_fixed_mapped = yes; then
  AC_DEFINE(HAVE_MMAP, 1,
	    [Define to 1 if you have a working `mmap' system call.])
fi
rm -f conftest.mmap
])# AC_FUNC_MMAP


# AU::AC_MMAP
# -----------
AU_ALIAS([AC_MMAP], [AC_FUNC_MMAP])


# AC_FUNC_OBSTACK
# ---------------
# Ensure obstack support.  Yeah, this is not exactly a `FUNC' check.
AN_FUNCTION([obstack_init], [AC_FUNC_OBSTACK])
AN_IDENTIFIER([obstack],    [AC_FUNC_OBSTACK])
AC_DEFUN([AC_FUNC_OBSTACK],
[AC_LIBSOURCES([obstack.h, obstack.c])dnl
AC_CACHE_CHECK([for obstacks], ac_cv_func_obstack,
[AC_LINK_IFELSE(
    [AC_LANG_PROGRAM([[@%:@include "obstack.h"]],
		     [[struct obstack *mem; obstack_free(mem,(char *) 0)]])],
		[ac_cv_func_obstack=yes],
		[ac_cv_func_obstack=no])])
if test $ac_cv_func_obstack = yes; then
  AC_DEFINE(HAVE_OBSTACK, 1, [Define to 1 if libc includes obstacks.])
else
  AC_LIBOBJ(obstack)
fi
])# AC_FUNC_OBSTACK


# AU::AM_FUNC_OBSTACK
# -------------------
AU_ALIAS([AM_FUNC_OBSTACK], [AC_FUNC_OBSTACK])



# _AC_FUNC_REALLOC_IF(IF-WORKS, IF-NOT)
# -------------------------------------
# If `realloc (0, 0)' is properly handled, run IF-WORKS, otherwise, IF-NOT.
AC_DEFUN([_AC_FUNC_REALLOC_IF],
[AC_REQUIRE([AC_HEADER_STDC])dnl
AC_CHECK_HEADERS(stdlib.h)
AC_CACHE_CHECK([for GNU libc compatible realloc], ac_cv_func_realloc_0_nonnull,
[AC_RUN_IFELSE(
[AC_LANG_PROGRAM(
[[#if STDC_HEADERS || HAVE_STDLIB_H
# include <stdlib.h>
#else
char *realloc ();
#endif
]],
		 [return ! realloc (0, 0);])],
	       [ac_cv_func_realloc_0_nonnull=yes],
	       [ac_cv_func_realloc_0_nonnull=no],
	       [ac_cv_func_realloc_0_nonnull=no])])
AS_IF([test $ac_cv_func_realloc_0_nonnull = yes], [$1], [$2])
])# AC_FUNC_REALLOC


# AC_FUNC_REALLOC
# ---------------
# Report whether `realloc (0, 0)' is properly handled, and replace realloc if
# needed.
AN_FUNCTION([realloc], [AC_FUNC_REALLOC])
AC_DEFUN([AC_FUNC_REALLOC],
[_AC_FUNC_REALLOC_IF(
  [AC_DEFINE([HAVE_REALLOC], 1,
	     [Define to 1 if your system has a GNU libc compatible `realloc'
	      function, and to 0 otherwise.])],
  [AC_DEFINE([HAVE_REALLOC], 0)
   AC_LIBOBJ([realloc])
   AC_DEFINE([realloc], [rpl_realloc],
      [Define to rpl_realloc if the replacement function should be used.])])
])# AC_FUNC_REALLOC


# AC_FUNC_SELECT_ARGTYPES
# -----------------------
# Determine the correct type to be passed to each of the `select'
# function's arguments, and define those types in `SELECT_TYPE_ARG1',
# `SELECT_TYPE_ARG234', and `SELECT_TYPE_ARG5'.
AN_FUNCTION([select], [AC_FUNC_SELECT_ARGTYPES])
AC_DEFUN([AC_FUNC_SELECT_ARGTYPES],
[AC_CHECK_HEADERS(sys/select.h sys/socket.h)
AC_CACHE_CHECK([types of arguments for select],
[ac_cv_func_select_args],
[for ac_arg234 in 'fd_set *' 'int *' 'void *'; do
 for ac_arg1 in 'int' 'size_t' 'unsigned long int' 'unsigned int'; do
  for ac_arg5 in 'struct timeval *' 'const struct timeval *'; do
   AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM(
[AC_INCLUDES_DEFAULT
#if HAVE_SYS_SELECT_H
# include <sys/select.h>
#endif
#if HAVE_SYS_SOCKET_H
# include <sys/socket.h>
#endif
],
			[extern int select ($ac_arg1,
					    $ac_arg234, $ac_arg234, $ac_arg234,
					    $ac_arg5);])],
	      [ac_cv_func_select_args="$ac_arg1,$ac_arg234,$ac_arg5"; break 3])
  done
 done
done
# Provide a safe default value.
: ${ac_cv_func_select_args='int,int *,struct timeval *'}
])
ac_save_IFS=$IFS; IFS=','
set dummy `echo "$ac_cv_func_select_args" | sed 's/\*/\*/g'`
IFS=$ac_save_IFS
shift
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG1, $[1],
		   [Define to the type of arg 1 for `select'.])
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG234, ($[2]),
		   [Define to the type of args 2, 3 and 4 for `select'.])
AC_DEFINE_UNQUOTED(SELECT_TYPE_ARG5, ($[3]),
		   [Define to the type of arg 5 for `select'.])
rm -f conftest*
])# AC_FUNC_SELECT_ARGTYPES


# AC_FUNC_SETPGRP
# ---------------
AN_FUNCTION([setpgrp], [AC_FUNC_SETPGRP])
AC_DEFUN([AC_FUNC_SETPGRP],
[AC_CACHE_CHECK(whether setpgrp takes no argument, ac_cv_func_setpgrp_void,
[AC_RUN_IFELSE(
[AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
[/* If this system has a BSD-style setpgrp which takes arguments,
  setpgrp(1, 1) will fail with ESRCH and return -1, in that case
  exit successfully. */
  return setpgrp (1,1) != -1;])],
	       [ac_cv_func_setpgrp_void=no],
	       [ac_cv_func_setpgrp_void=yes],
	       [AC_MSG_ERROR([cannot check setpgrp when cross compiling])])])
if test $ac_cv_func_setpgrp_void = yes; then
  AC_DEFINE(SETPGRP_VOID, 1,
	    [Define to 1 if the `setpgrp' function takes no argument.])
fi
])# AC_FUNC_SETPGRP


# _AC_FUNC_STAT(STAT | LSTAT)
# ---------------------------
# Determine whether stat or lstat have the bug that it succeeds when
# given the zero-length file name argument.  The stat and lstat from
# SunOS4.1.4 and the Hurd (as of 1998-11-01) do this.
#
# If it does, then define HAVE_STAT_EMPTY_STRING_BUG (or
# HAVE_LSTAT_EMPTY_STRING_BUG) and arrange to compile the wrapper
# function.
m4_define([_AC_FUNC_STAT],
[AC_REQUIRE([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])dnl
AC_CACHE_CHECK([whether $1 accepts an empty string],
	       [ac_cv_func_$1_empty_string_bug],
[AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
[[struct stat sbuf;
  return $1 ("", &sbuf) == 0;]])],
	    [ac_cv_func_$1_empty_string_bug=no],
	    [ac_cv_func_$1_empty_string_bug=yes],
	    [ac_cv_func_$1_empty_string_bug=yes])])
if test $ac_cv_func_$1_empty_string_bug = yes; then
  AC_LIBOBJ([$1])
  AC_DEFINE_UNQUOTED(AS_TR_CPP([HAVE_$1_EMPTY_STRING_BUG]), 1,
		     [Define to 1 if `$1' has the bug that it succeeds when
		      given the zero-length file name argument.])
fi
])# _AC_FUNC_STAT


# AC_FUNC_STAT & AC_FUNC_LSTAT
# ----------------------------
AN_FUNCTION([stat], [AC_FUNC_STAT])
AC_DEFUN([AC_FUNC_STAT],  [_AC_FUNC_STAT(stat)])
AN_FUNCTION([lstat], [AC_FUNC_LSTAT])
AC_DEFUN([AC_FUNC_LSTAT], [_AC_FUNC_STAT(lstat)])


# _AC_LIBOBJ_STRTOD
# -----------------
m4_define([_AC_LIBOBJ_STRTOD],
[AC_LIBOBJ(strtod)
AC_CHECK_FUNC(pow)
if test $ac_cv_func_pow = no; then
  AC_CHECK_LIB(m, pow,
	       [POW_LIB=-lm],
	       [AC_MSG_WARN([cannot find library containing definition of pow])])
fi
])# _AC_LIBOBJ_STRTOD


# AC_FUNC_STRTOD
# --------------
AN_FUNCTION([strtod], [AC_FUNC_STRTOD])
AC_DEFUN([AC_FUNC_STRTOD],
[AC_SUBST(POW_LIB)dnl
AC_CACHE_CHECK(for working strtod, ac_cv_func_strtod,
[AC_RUN_IFELSE([AC_LANG_SOURCE([[
]AC_INCLUDES_DEFAULT[
#ifndef strtod
double strtod ();
#endif
int
main()
{
  {
    /* Some versions of Linux strtod mis-parse strings with leading '+'.  */
    char *string = " +69";
    char *term;
    double value;
    value = strtod (string, &term);
    if (value != 69 || term != (string + 4))
      return 1;
  }

  {
    /* Under Solaris 2.4, strtod returns the wrong value for the
       terminating character under some conditions.  */
    char *string = "NaN";
    char *term;
    strtod (string, &term);
    if (term != string && *(term - 1) == 0)
      return 1;
  }
  return 0;
}
]])],
	       ac_cv_func_strtod=yes,
	       ac_cv_func_strtod=no,
	       ac_cv_func_strtod=no)])
if test $ac_cv_func_strtod = no; then
  _AC_LIBOBJ_STRTOD
fi
])


# AC_FUNC_STRTOLD
# ---------------
AC_DEFUN([AC_FUNC_STRTOLD],
[
  AC_CACHE_CHECK([whether strtold conforms to C99],
    [ac_cv_func_strtold],
    [AC_COMPILE_IFELSE(
       [AC_LANG_PROGRAM(
	  [[/* On HP-UX before 11.23, strtold returns a struct instead of
		long double.  Reject implementations like that, by requiring
		compatibility with the C99 prototype.  */
#	     include <stdlib.h>
	     static long double (*p) (char const *, char **) = strtold;
	     static long double
	     test (char const *nptr, char **endptr)
	     {
	       long double r;
	       r = strtold (nptr, endptr);
	       return r;
	     }]],
	   [[return test ("1.0", NULL) != 1 || p ("1.0", NULL) != 1;]])],
       [ac_cv_func_strtold=yes],
       [ac_cv_func_strtold=no])])
  if test $ac_cv_func_strtold = yes; then
    AC_DEFINE([HAVE_STRTOLD], 1,
      [Define to 1 if strtold exists and conforms to C99.])
  fi
])# AC_FUNC_STRTOLD


# AU::AM_FUNC_STRTOD
# ------------------
AU_ALIAS([AM_FUNC_STRTOD], [AC_FUNC_STRTOD])


# AC_FUNC_STRERROR_R
# ------------------
AN_FUNCTION([strerror_r], [AC_FUNC_STRERROR_R])
AC_DEFUN([AC_FUNC_STRERROR_R],
[AC_CHECK_DECLS([strerror_r])
AC_CHECK_FUNCS([strerror_r])
AC_CACHE_CHECK([whether strerror_r returns char *],
	       ac_cv_func_strerror_r_char_p,
   [
    ac_cv_func_strerror_r_char_p=no
    if test $ac_cv_have_decl_strerror_r = yes; then
      AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],
	[[
	  char buf[100];
	  char x = *strerror_r (0, buf, sizeof buf);
	  char *p = strerror_r (0, buf, sizeof buf);
	  return !p || x;
	]])],
			ac_cv_func_strerror_r_char_p=yes)
    else
      # strerror_r is not declared.  Choose between
      # systems that have relatively inaccessible declarations for the
      # function.  BeOS and DEC UNIX 4.0 fall in this category, but the
      # former has a strerror_r that returns char*, while the latter
      # has a strerror_r that returns `int'.
      # This test should segfault on the DEC system.
      AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT
	extern char *strerror_r ();],
	[[char buf[100];
	  char x = *strerror_r (0, buf, sizeof buf);
	  return ! isalpha (x);]])],
		    ac_cv_func_strerror_r_char_p=yes, , :)
    fi
  ])
if test $ac_cv_func_strerror_r_char_p = yes; then
  AC_DEFINE([STRERROR_R_CHAR_P], 1,
	    [Define to 1 if strerror_r returns char *.])
fi
])# AC_FUNC_STRERROR_R


# AC_FUNC_STRFTIME
# ----------------