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diff --git a/gnulib/import/filenamecat-lgpl.c b/gnulib/import/filenamecat-lgpl.c
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+/* Concatenate two arbitrary file names.
+
+ Copyright (C) 1996-2007, 2009-2016 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. */
+
+#include <config.h>
+
+/* Specification. */
+#include "filenamecat.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "dirname.h"
+
+#if ! HAVE_MEMPCPY && ! defined mempcpy
+# define mempcpy(D, S, N) ((void *) ((char *) memcpy (D, S, N) + (N)))
+#endif
+
+/* Return the longest suffix of F that is a relative file name.
+ If it has no such suffix, return the empty string. */
+
+static char const * _GL_ATTRIBUTE_PURE
+longest_relative_suffix (char const *f)
+{
+ for (f += FILE_SYSTEM_PREFIX_LEN (f); ISSLASH (*f); f++)
+ continue;
+ return f;
+}
+
+/* Concatenate two file name components, DIR and ABASE, in
+ newly-allocated storage and return the result.
+ The resulting file name F is such that the commands "ls F" and "(cd
+ DIR; ls BASE)" refer to the same file, where BASE is ABASE with any
+ file system prefixes and leading separators removed.
+ Arrange for a directory separator if necessary between DIR and BASE
+ in the result, removing any redundant separators.
+ In any case, if BASE_IN_RESULT is non-NULL, set
+ *BASE_IN_RESULT to point to the copy of ABASE in the returned
+ concatenation. However, if ABASE begins with more than one slash,
+ set *BASE_IN_RESULT to point to the sole corresponding slash that
+ is copied into the result buffer.
+
+ Return NULL if malloc fails. */
+
+char *
+mfile_name_concat (char const *dir, char const *abase, char **base_in_result)
+{
+ char const *dirbase = last_component (dir);
+ size_t dirbaselen = base_len (dirbase);
+ size_t dirlen = dirbase - dir + dirbaselen;
+ size_t needs_separator = (dirbaselen && ! ISSLASH (dirbase[dirbaselen - 1]));
+
+ char const *base = longest_relative_suffix (abase);
+ size_t baselen = strlen (base);
+
+ char *p_concat = malloc (dirlen + needs_separator + baselen + 1);
+ char *p;
+
+ if (p_concat == NULL)
+ return NULL;
+
+ p = mempcpy (p_concat, dir, dirlen);
+ *p = DIRECTORY_SEPARATOR;
+ p += needs_separator;
+
+ if (base_in_result)
+ *base_in_result = p - IS_ABSOLUTE_FILE_NAME (abase);
+
+ p = mempcpy (p, base, baselen);
+ *p = '\0';
+
+ return p_concat;
+}