| /* Read symbolic links into a buffer without size limitation, relative to fd. |
| |
| Copyright (C) 2011-2019 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 <https://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() |
| <https://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 */ |