gnulib/import/m4/open.m4

   1 # open.m4 serial 14
   2 dnl Copyright (C) 2007-2016 Free Software Foundation, Inc.
   3 dnl This file is free software; the Free Software Foundation
   4 dnl gives unlimited permission to copy and/or distribute it,
   5 dnl with or without modifications, as long as this notice is preserved.
   6
   7 AC_DEFUN([gl_FUNC_OPEN],
   8 [
   9   AC_REQUIRE([AC_CANONICAL_HOST])
  10   case "$host_os" in
  11     mingw* | pw*)
  12       REPLACE_OPEN=1
  13       ;;
  14     *)
  15       dnl open("foo/") should not create a file when the file name has a
  16       dnl trailing slash.  FreeBSD only has the problem on symlinks.
  17       AC_CHECK_FUNCS_ONCE([lstat])
  18       AC_CACHE_CHECK([whether open recognizes a trailing slash],
  19         [gl_cv_func_open_slash],
  20         [# Assume that if we have lstat, we can also check symlinks.
  21           if test $ac_cv_func_lstat = yes; then
  22             touch conftest.tmp
  23             ln -s conftest.tmp conftest.lnk
  24           fi
  25           AC_RUN_IFELSE(
  26             [AC_LANG_SOURCE([[
  27 #include <fcntl.h>
  28 #if HAVE_UNISTD_H
  29 # include <unistd.h>
  30 #endif
  31 int main ()
  32 {
  33   int result = 0;
  34 #if HAVE_LSTAT
  35   if (open ("conftest.lnk/", O_RDONLY) != -1)
  36     result |= 1;
  37 #endif
  38   if (open ("conftest.sl/", O_CREAT, 0600) >= 0)
  39     result |= 2;
  40   return result;
  41 }]])],
  42             [gl_cv_func_open_slash=yes],
  43             [gl_cv_func_open_slash=no],
  44             [
  45 changequote(,)dnl
  46              case "$host_os" in
  47                freebsd* | aix* | hpux* | solaris2.[0-9] | solaris2.[0-9].*)
  48                  gl_cv_func_open_slash="guessing no" ;;
  49                *)
  50                  gl_cv_func_open_slash="guessing yes" ;;
  51              esac
  52 changequote([,])dnl
  53             ])
  54           rm -f conftest.sl conftest.tmp conftest.lnk
  55         ])
  56       case "$gl_cv_func_open_slash" in
  57         *no)
  58           AC_DEFINE([OPEN_TRAILING_SLASH_BUG], [1],
  59             [Define to 1 if open() fails to recognize a trailing slash.])
  60           REPLACE_OPEN=1
  61           ;;
  62       esac
  63       ;;
  64   esac
  65   dnl Replace open() for supporting the gnulib-defined fchdir() function,
  66   dnl to keep fchdir's bookkeeping up-to-date.
  67   m4_ifdef([gl_FUNC_FCHDIR], [
  68     if test $REPLACE_OPEN = 0; then
  69       gl_TEST_FCHDIR
  70       if test $HAVE_FCHDIR = 0; then
  71         REPLACE_OPEN=1
  72       fi
  73     fi
  74   ])
  75   dnl Replace open() for supporting the gnulib-defined O_NONBLOCK flag.
  76   m4_ifdef([gl_NONBLOCKING_IO], [
  77     if test $REPLACE_OPEN = 0; then
  78       gl_NONBLOCKING_IO
  79       if test $gl_cv_have_open_O_NONBLOCK != yes; then
  80         REPLACE_OPEN=1
  81       fi
  82     fi
  83   ])
  84 ])
  85
  86 # Prerequisites of lib/open.c.
  87 AC_DEFUN([gl_PREREQ_OPEN],
  88 [
  89   AC_REQUIRE([gl_PROMOTED_TYPE_MODE_T])
  90   :
  91 ])