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authorPaul Eggert <eggert@cs.ucla.edu>2005-06-02 04:59:10 +0000
committerPaul Eggert <eggert@cs.ucla.edu>2005-06-02 04:59:10 +0000
commit1885506f1e01d687b3a206eac7f20a8c49f273ee (patch)
treeb91c1312513004b71c02ef832b135b08b4c263ff /lib
parent3a0841772cdad328b7a4e81a4b9ab497e0375c94 (diff)
downloadcoreutils-1885506f1e01d687b3a206eac7f20a8c49f273ee.tar.xz
Renamed from path-concat.c.
(file_name_concat): Renamed from path_concat. All callers changed. [TEST_FILE_NAME_CONCAT]: Renamed from TEST_PATH_CONCAT.
Diffstat (limited to 'lib')
-rw-r--r--lib/filenamecat.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/lib/filenamecat.c b/lib/filenamecat.c
new file mode 100644
index 000000000..f56697a6d
--- /dev/null
+++ b/lib/filenamecat.c
@@ -0,0 +1,126 @@
+/* Concatenate two arbitrary file names.
+
+ Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 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 2, 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, write to the Free Software Foundation,
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+/* Written by Jim Meyering. */
+
+#if HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+/* Specification. */
+#include "filenamecat.h"
+
+#include <string.h>
+
+#include "dirname.h"
+#include "xalloc.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 *
+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.
+
+ Report an error if memory is exhausted. */
+
+char *
+file_name_concat (char const *dir, char const *abase, char **base_in_result)
+{
+ char const *dirbase = base_name (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 = xmalloc (dirlen + needs_separator + baselen + 1);
+ char *p;
+
+ 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;
+}
+
+#ifdef TEST_FILE_NAME_CONCAT
+# include <stdlib.h>
+# include <stdio.h>
+int
+main ()
+{
+ static char const *const tests[][3] =
+ {
+ {"a", "b", "a/b"},
+ {"a/", "b", "a/b"},
+ {"a/", "/b", "a/b"},
+ {"a", "/b", "a/b"},
+
+ {"/", "b", "/b"},
+ {"/", "/b", "/b"},
+ {"/", "/", "/"},
+ {"a", "/", "a/"}, /* this might deserve a diagnostic */
+ {"/a", "/", "/a/"}, /* this might deserve a diagnostic */
+ {"a", "//b", "a/b"},
+ };
+ size_t i;
+ bool fail = false;
+ for (i = 0; i < sizeof tests / sizeof tests[0]; i++)
+ {
+ char *base_in_result;
+ char const *const *t = tests[i];
+ char *res = file_name_concat (t[0], t[1], &base_in_result);
+ if (strcmp (res, t[2]) != 0)
+ {
+ printf ("got %s, expected %s\n", res, t[2]);
+ fail = true;
+ }
+ }
+ exit (fail ? EXIT_FAILURE : EXIT_SUCCESS);
+}
+#endif