Mercurial > hg > octave-kai > gnulib-hg
annotate tests/zerosize-ptr.h @ 17168:1b3c19ad4b17
math: better 'inline'
* lib/math.c: New file.
* lib/math.in.h (_GL_MATH_INLINE):
New macro. Replace all uses of 'static inline' with it.
Use _GL_INLINE_HEADER_BEGIN, _GL_INLINE_HEADER_END.
* m4/math_h.m4 (gl_MATH_H):
Do not require AC_C_INLINE.
* modules/math (Files, lib_SOURCES):
Add lib/math.c.
(Depends-on): Add extern-inline.
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Tue, 20 Nov 2012 22:25:06 -0800 |
parents | 8250f2777afc |
children | e542fd46ad6f |
rev | line source |
---|---|
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
1 /* Return a pointer to a zero-size object in memory. |
16201
8250f2777afc
maint: update all copyright year number ranges
Jim Meyering <meyering@redhat.com>
parents:
14079
diff
changeset
|
2 Copyright (C) 2009-2012 Free Software Foundation, Inc. |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
3 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
4 This program is free software: you can redistribute it and/or modify |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
5 it under the terms of the GNU General Public License as published by |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
6 the Free Software Foundation; either version 3 of the License, or |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
7 (at your option) any later version. |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
8 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
9 This program is distributed in the hope that it will be useful, |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
10 but WITHOUT ANY WARRANTY; without even the implied warranty of |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
12 GNU General Public License for more details. |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
13 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
14 You should have received a copy of the GNU General Public License |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
16 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
17 /* ISO C 99 does not allow memcmp(), memchr() etc. to be invoked with a NULL |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
18 argument. Therefore this file produces a non-NULL pointer which cannot |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
19 be dereferenced, if possible. */ |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
20 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
21 #include <stdlib.h> |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
22 |
11580
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
23 /* Test whether mmap() and mprotect() are available. |
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
24 We don't use HAVE_MMAP, because AC_FUNC_MMAP would not define it on HP-UX. |
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
25 HAVE_MPROTECT is not enough, because mingw does not have mmap() but has an |
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
26 mprotect() function in libgcc.a. */ |
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
27 #if HAVE_SYS_MMAN_H && HAVE_MPROTECT |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
28 # include <fcntl.h> |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
29 # include <unistd.h> |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
30 # include <sys/types.h> |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
31 # include <sys/mman.h> |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
32 /* Define MAP_FILE when it isn't otherwise. */ |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
33 # ifndef MAP_FILE |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
34 # define MAP_FILE 0 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
35 # endif |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
36 #endif |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
37 |
11598
58b1732d052a
Check that memchr does not read past the first occurrence of the byte.
Bruno Haible <bruno@clisp.org>
parents:
11580
diff
changeset
|
38 /* Return a pointer to a zero-size object in memory (that is, actually, a |
58b1732d052a
Check that memchr does not read past the first occurrence of the byte.
Bruno Haible <bruno@clisp.org>
parents:
11580
diff
changeset
|
39 pointer to a page boundary where the previous page is readable and writable |
58b1732d052a
Check that memchr does not read past the first occurrence of the byte.
Bruno Haible <bruno@clisp.org>
parents:
11580
diff
changeset
|
40 and the next page is neither readable not writable), if possible. |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
41 Return NULL otherwise. */ |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
42 |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
43 static void * |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
44 zerosize_ptr (void) |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
45 { |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
46 /* Use mmap and mprotect when they exist. Don't test HAVE_MMAP, because it is |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
47 not defined on HP-UX 11 (since it does not support MAP_FIXED). */ |
11580
89e9741f299f
Make zeroptr.h work on mingw.
Bruno Haible <bruno@clisp.org>
parents:
11570
diff
changeset
|
48 #if HAVE_SYS_MMAN_H && HAVE_MPROTECT |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
49 # if HAVE_MAP_ANONYMOUS |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
50 const int flags = MAP_ANONYMOUS | MAP_PRIVATE; |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
51 const int fd = -1; |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
52 # else /* !HAVE_MAP_ANONYMOUS */ |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
53 const int flags = MAP_FILE | MAP_PRIVATE; |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
54 int fd = open ("/dev/zero", O_RDONLY, 0666); |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
55 if (fd >= 0) |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
56 # endif |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
57 { |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
58 int pagesize = getpagesize (); |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
59 char *two_pages = |
12421
e8d2c6fc33ad
Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents:
11598
diff
changeset
|
60 (char *) mmap (NULL, 2 * pagesize, PROT_READ | PROT_WRITE, |
e8d2c6fc33ad
Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents:
11598
diff
changeset
|
61 flags, fd, 0); |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
62 if (two_pages != (char *)(-1) |
12421
e8d2c6fc33ad
Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents:
11598
diff
changeset
|
63 && mprotect (two_pages + pagesize, pagesize, PROT_NONE) == 0) |
e8d2c6fc33ad
Use spaces for indentation, not tabs.
Bruno Haible <bruno@clisp.org>
parents:
11598
diff
changeset
|
64 return two_pages + pagesize; |
11570
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
65 } |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
66 #endif |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
67 return NULL; |
1e84e9b3384a
Make some tests ISO C 99 compliant.
Bruno Haible <bruno@clisp.org>
parents:
diff
changeset
|
68 } |