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+/* areadlink.c -- readlink wrapper to return the link name in malloc'd storage
+ Unlike xreadlink and xreadlink_with_size, don't ever call exit.
+
+ Copyright (C) 2001, 2003-2007, 2009-2020 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 Jim Meyering <jim@meyering.net>
+ and Bruno Haible <bruno@clisp.org>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "areadlink.h"
+
+#include "careadlinkat.h"
+
+#include <stdlib.h>
+#include <unistd.h>
+
+/* Get the symbolic link value of FILENAME and put it into BUFFER, with
+ size BUFFER_SIZE. This function acts like readlink but has
+ readlinkat's signature. */
+static ssize_t
+careadlinkatcwd (int fd, char const *filename, char *buffer,
+ size_t buffer_size)
+{
+ /* FD must be AT_FDCWD here, otherwise the caller is using this
+ function in contexts it was not meant for. */
+ if (fd != AT_FDCWD)
+ abort ();
+ return readlink (filename, buffer, buffer_size);
+}
+
+/* Call readlink to get the symbolic link value of FILENAME.
+ Return a pointer to that NUL-terminated string in malloc'd storage.
+ If readlink fails, return NULL and set errno.
+ If allocation fails, or if the link value is longer than SIZE_MAX :-),
+ return NULL and set errno to ENOMEM. */
+
+char *
+areadlink (char const *filename)
+{
+ return careadlinkat (AT_FDCWD, filename, NULL, 0, NULL, careadlinkatcwd);
+}