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| author | Florian Weimer <fweimer@redhat.com> | 2017-11-02 12:14:01 +0100 |
|---|---|---|
| committer | Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com> | 2018-04-06 16:23:56 -0300 |
| commit | d9c54360ca92a92ee8ee587f15a3cfc64fe4cb37 (patch) | |
| tree | 56f8101f41a0861767b72dfd7cab1f84a00fc631 | |
| parent | f87adbcaa47de2109e1c4561a2badf8aa82bc349 (diff) | |
| download | glibc-d9c54360ca92a92ee8ee587f15a3cfc64fe4cb37.tar.gz glibc-d9c54360ca92a92ee8ee587f15a3cfc64fe4cb37.tar.xz glibc-d9c54360ca92a92ee8ee587f15a3cfc64fe4cb37.zip | |
<array_length.h>: New array_length and array_end macros
(cherry picked from commit c94a5688fb1228a862b2d4a3f1239cdc0e3349e5)
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | include/array_length.h | 36 |
2 files changed, 41 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 3c8fd97fe0..59d00dbb4e 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2017-11-02 Florian Weimer <fweimer@redhat.com> + + Add array_length and array_end macros. + * include/array_length.h: New file. + 2017-12-14 Florian Weimer <fweimer@redhat.com> [BZ #22607] diff --git a/include/array_length.h b/include/array_length.h new file mode 100644 index 0000000000..cb4a8b2a56 --- /dev/null +++ b/include/array_length.h @@ -0,0 +1,36 @@ +/* The array_length and array_end macros. + Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _ARRAY_LENGTH_H +#define _ARRAY_LENGTH_H + +/* array_length (VAR) is the number of elements in the array VAR. VAR + must evaluate to an array, not a pointer. */ +#define array_length(var) \ + __extension__ ({ \ + _Static_assert (!__builtin_types_compatible_p \ + (__typeof (var), __typeof (&(var)[0])), \ + "argument must be an array"); \ + sizeof (var) / sizeof ((var)[0]); \ + }) + +/* array_end (VAR) is a pointer one past the end of the array VAR. + VAR must evaluate to an array, not a pointer. */ +#define array_end(var) (&(var)[array_length (var)]) + +#endif /* _ARRAY_LENGTH_H */ |