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author | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-05-16 09:22:21 +0000 |
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committer | Lorry Tar Creator <lorry-tar-importer@lorry> | 2016-05-16 09:22:21 +0000 |
commit | d4fdeab4db0d0e699c8fbbb07f12c4e1f64d0f94 (patch) | |
tree | 72231a38ed1cdd48ac6e02acb8b3917acb9dbcf4 /gnu/careadlinkat.h | |
download | tar-tarball-d4fdeab4db0d0e699c8fbbb07f12c4e1f64d0f94.tar.gz |
Diffstat (limited to 'gnu/careadlinkat.h')
-rw-r--r-- | gnu/careadlinkat.h | 67 |
1 files changed, 67 insertions, 0 deletions
diff --git a/gnu/careadlinkat.h b/gnu/careadlinkat.h new file mode 100644 index 0000000..4eb9fcc --- /dev/null +++ b/gnu/careadlinkat.h @@ -0,0 +1,67 @@ +/* Read symbolic links into a buffer without size limitation, relative to fd. + + Copyright (C) 2011-2015 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 Paul Eggert, Bruno Haible, and Jim Meyering. */ + +#ifndef _GL_CAREADLINKAT_H +#define _GL_CAREADLINKAT_H + +#include <fcntl.h> +#include <unistd.h> + +struct allocator; + +/* Assuming the current directory is FD, get the symbolic link value + of FILENAME as a null-terminated string and put it into a buffer. + If FD is AT_FDCWD, FILENAME is interpreted relative to the current + working directory, as in openat. + + If the link is small enough to fit into BUFFER put it there. + BUFFER's size is BUFFER_SIZE, and BUFFER can be null + if BUFFER_SIZE is zero. + + If the link is not small, put it into a dynamically allocated + buffer managed by ALLOC. It is the caller's responsibility to free + the returned value if it is nonnull and is not BUFFER. + + The PREADLINKAT function specifies how to read links. It operates + like POSIX readlinkat() + <http://pubs.opengroup.org/onlinepubs/9699919799/functions/readlink.html> + but can assume that its first argument is the same as FD. + + If successful, return the buffer address; otherwise return NULL and + set errno. */ + +char *careadlinkat (int fd, char const *filename, + char *buffer, size_t buffer_size, + struct allocator const *alloc, + ssize_t (*preadlinkat) (int, char const *, + char *, size_t)); + +/* Suitable value for careadlinkat's FD argument. */ +#if HAVE_READLINKAT +/* AT_FDCWD is declared in <fcntl.h>. */ +#else +/* Define AT_FDCWD independently, so that the careadlinkat module does + not depend on the fcntl-h module. We might as well use the same value + as fcntl-h. */ +# ifndef AT_FDCWD +# define AT_FDCWD (-3041965) +# endif +#endif + +#endif /* _GL_CAREADLINKAT_H */ |