57 lines
2.0 KiB
C
57 lines
2.0 KiB
C
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/* areadlink.c -- readlink wrapper to return the link name in malloc'd storage
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Unlike xreadlink and xreadlink_with_size, don't ever call exit.
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Copyright (C) 2001, 2003-2007, 2009-2022 Free Software Foundation, Inc.
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This file is free software: you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as
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published by the Free Software Foundation; either version 2.1 of the
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License, or (at your option) any later version.
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This file is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with this program. If not, see <https://www.gnu.org/licenses/>. */
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/* Written by Jim Meyering <jim@meyering.net>
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and Bruno Haible <bruno@clisp.org>. */
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#include <config.h>
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/* Specification. */
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#include "areadlink.h"
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#include "careadlinkat.h"
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#include <stdlib.h>
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#include <unistd.h>
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/* Get the symbolic link value of FILENAME and put it into BUFFER, with
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size BUFFER_SIZE. This function acts like readlink but has
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readlinkat's signature. */
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static ssize_t
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careadlinkatcwd (int fd, char const *filename, char *buffer,
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size_t buffer_size)
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{
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/* FD must be AT_FDCWD here, otherwise the caller is using this
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function in contexts it was not meant for. */
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if (fd != AT_FDCWD)
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abort ();
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return readlink (filename, buffer, buffer_size);
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}
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/* Call readlink to get the symbolic link value of FILENAME.
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Return a pointer to that NUL-terminated string in malloc'd storage.
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If readlink fails, return NULL and set errno.
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If allocation fails, or if the link value is longer than SIZE_MAX :-),
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return NULL and set errno to ENOMEM. */
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char *
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areadlink (char const *filename)
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{
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return careadlinkat (AT_FDCWD, filename, NULL, 0, NULL, careadlinkatcwd);
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}
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