diff options
author | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-05-16 09:22:21 +0000 |
---|---|---|
committer | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-05-16 09:22:21 +0000 |
commit | d4fdeab4db0d0e699c8fbbb07f12c4e1f64d0f94 (patch) | |
tree | 72231a38ed1cdd48ac6e02acb8b3917acb9dbcf4 /gnu/areadlinkat.c | |
download | tar-tarball-d4fdeab4db0d0e699c8fbbb07f12c4e1f64d0f94.tar.gz |
Diffstat (limited to 'gnu/areadlinkat.c')
-rw-r--r-- | gnu/areadlinkat.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/gnu/areadlinkat.c b/gnu/areadlinkat.c new file mode 100644 index 0000000..b639056 --- /dev/null +++ b/gnu/areadlinkat.c @@ -0,0 +1,65 @@ +/* areadlinkat.c -- readlinkat wrapper to return malloc'd link name + Unlike xreadlinkat, only call exit on failure to change directory. + + Copyright (C) 2001, 2003-2007, 2009-2015 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +/* Written by Jim Meyering <jim@meyering.net>, + and Bruno Haible <bruno@clisp.org>, + and Eric Blake <ebb9@byu.net>. */ + +#include <config.h> + +/* Specification. */ +#include "areadlink.h" + +#include "careadlinkat.h" + +#if HAVE_READLINKAT + +/* Call readlinkat to get the symbolic link value of FILENAME relative to FD. + Return a pointer to that NUL-terminated string in malloc'd storage. + If readlinkat fails, return NULL and set errno (although failure to + change directory will issue a diagnostic and exit). + If allocation fails, or if the link value is longer than SIZE_MAX :-), + return NULL and set errno to ENOMEM. */ + +char * +areadlinkat (int fd, char const *filename) +{ + return careadlinkat (fd, filename, NULL, 0, NULL, readlinkat); +} + +#else /* !HAVE_READLINKAT */ + +/* It is more efficient to change directories only once and call + areadlink, rather than repeatedly call the replacement + readlinkat. */ + +# define AT_FUNC_NAME areadlinkat +# define AT_FUNC_F1 areadlink +# define AT_FUNC_POST_FILE_PARAM_DECLS /* empty */ +# define AT_FUNC_POST_FILE_ARGS /* empty */ +# define AT_FUNC_RESULT char * +# define AT_FUNC_FAIL NULL +# include "at-func.c" +# undef AT_FUNC_NAME +# undef AT_FUNC_F1 +# undef AT_FUNC_POST_FILE_PARAM_DECLS +# undef AT_FUNC_POST_FILE_ARGS +# undef AT_FUNC_RESULT +# undef AT_FUNC_FAIL + +#endif /* !HAVE_READLINKAT */ |