comparison m4/mmap-anon.m4 @ 398:7987ee447833 3.0-beta1

Added generated files for release
author lost@l-w.ca
date Fri, 23 Jul 2010 17:18:52 -0600
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397:09fe7c40a082 398:7987ee447833
1 # mmap-anon.m4 serial 8
2 dnl Copyright (C) 2005, 2007, 2009-2010 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 # Detect how mmap can be used to create anonymous (not file-backed) memory
8 # mappings.
9 # - On Linux, AIX, OSF/1, Solaris, Cygwin, Interix, Haiku, both MAP_ANONYMOUS
10 # and MAP_ANON exist and have the same value.
11 # - On HP-UX, only MAP_ANONYMOUS exists.
12 # - On MacOS X, FreeBSD, NetBSD, OpenBSD, only MAP_ANON exists.
13 # - On IRIX, neither exists, and a file descriptor opened to /dev/zero must be
14 # used.
15
16 AC_DEFUN([gl_FUNC_MMAP_ANON],
17 [
18 dnl Work around a bug of AC_EGREP_CPP in autoconf-2.57.
19 AC_REQUIRE([AC_PROG_CPP])
20 AC_REQUIRE([AC_PROG_EGREP])
21
22 dnl Persuade glibc <sys/mman.h> to define MAP_ANONYMOUS.
23 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
24
25 # Check for mmap(). Don't use AC_FUNC_MMAP, because it checks too much: it
26 # fails on HP-UX 11, because MAP_FIXED mappings do not work. But this is
27 # irrelevant for anonymous mappings.
28 AC_CHECK_FUNC([mmap], [gl_have_mmap=yes], [gl_have_mmap=no])
29
30 # Try to allow MAP_ANONYMOUS.
31 gl_have_mmap_anonymous=no
32 if test $gl_have_mmap = yes; then
33 AC_MSG_CHECKING([for MAP_ANONYMOUS])
34 AC_EGREP_CPP([I cant identify this map.], [
35 #include <sys/mman.h>
36 #ifdef MAP_ANONYMOUS
37 I cant identify this map.
38 #endif
39 ],
40 [gl_have_mmap_anonymous=yes])
41 if test $gl_have_mmap_anonymous != yes; then
42 AC_EGREP_CPP([I cant identify this map.], [
43 #include <sys/mman.h>
44 #ifdef MAP_ANON
45 I cant identify this map.
46 #endif
47 ],
48 [AC_DEFINE([MAP_ANONYMOUS], [MAP_ANON],
49 [Define to a substitute value for mmap()'s MAP_ANONYMOUS flag.])
50 gl_have_mmap_anonymous=yes])
51 fi
52 AC_MSG_RESULT([$gl_have_mmap_anonymous])
53 if test $gl_have_mmap_anonymous = yes; then
54 AC_DEFINE([HAVE_MAP_ANONYMOUS], [1],
55 [Define to 1 if mmap()'s MAP_ANONYMOUS flag is available after including
56 config.h and <sys/mman.h>.])
57 fi
58 fi
59 ])