-/* basename.c -- return the last element in a path */
+/* basename.c -- return the last element in a file name
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+ Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006 Free
+ Software Foundation, Inc.
-#ifndef FILESYSTEM_PREFIX_LEN
-# define FILESYSTEM_PREFIX_LEN(f) 0
-#endif
+ 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.
-#ifndef ISSLASH
-# define ISSLASH(c) ((c) == '/')
-#endif
+ 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.
-/* In general, we can't use the builtin `basename' function if available,
- since it has different meanings in different environments.
- In some environments the builtin `basename' modifies its argument. */
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
+
+#include <config.h>
+
+#include "dirname.h"
+
+#include <string.h>
+#include "xalloc.h"
+#include "xstrndup.h"
+
+/* Return the address of the last file name component of NAME. If
+ NAME has no relative file name components because it is a file
+ system root, return the empty string. */
char *
-base_name (name)
- char const *name;
+last_component (char const *name)
{
- char const *base = name += FILESYSTEM_PREFIX_LEN (name);
+ char const *base = name + FILE_SYSTEM_PREFIX_LEN (name);
+ char const *p;
+ bool saw_slash = false;
- for (; *name; name++)
- if (ISSLASH (*name))
- base = name + 1;
+ while (ISSLASH (*base))
+ base++;
+
+ for (p = base; *p; p++)
+ {
+ if (ISSLASH (*p))
+ saw_slash = true;
+ else if (saw_slash)
+ {
+ base = p;
+ saw_slash = false;
+ }
+ }
return (char *) base;
}
-#ifdef STDC_HEADERS
-# include <stdlib.h>
-#else
-char *malloc ();
-#endif
+
+/* In general, we can't use the builtin `basename' function if available,
+ since it has different meanings in different environments.
+ In some environments the builtin `basename' modifies its argument.
+
+ Return the last file name component of NAME, allocated with
+ xmalloc. On systems with drive letters, a leading "./"
+ distinguishes relative names that would otherwise look like a drive
+ letter. Unlike POSIX basename(), NAME cannot be NULL,
+ base_name("") returns "", and the first trailing slash is not
+ stripped.
+
+ If lstat (NAME) would succeed, then { chdir (dir_name (NAME));
+ lstat (base_name (NAME)); } will access the same file. Likewise,
+ if the sequence { chdir (dir_name (NAME));
+ rename (base_name (NAME), "foo"); } succeeds, you have renamed NAME
+ to "foo" in the same directory NAME was in. */
char *
-base_name_strip_trailing_slashes (name)
- char const *name;
+base_name (char const *name)
{
- char const *end_p = name += FILESYSTEM_PREFIX_LEN (name);
- char const *first, *p;
- char *base;
- int length;
-
- /* Make END_P point to the byte after the last non-slash character
- in NAME if one exists. */
- for (p = name; *p; p++)
- if (!ISSLASH (*p))
- end_p = p + 1;
-
- if (end_p == name)
- {
- first = end_p;
- }
- else
+ char const *base = last_component (name);
+ size_t length;
+
+ /* If there is no last component, then name is a file system root or the
+ empty string. */
+ if (! *base)
+ return xstrndup (name, base_len (name));
+
+ /* Collapse a sequence of trailing slashes into one. */
+ length = base_len (base);
+ if (ISSLASH (base[length]))
+ length++;
+
+ /* On systems with drive letters, `a/b:c' must return `./b:c' rather
+ than `b:c' to avoid confusion with a drive letter. On systems
+ with pure POSIX semantics, this is not an issue. */
+ if (FILE_SYSTEM_PREFIX_LEN (base))
{
- first = end_p - 1;
- while (first > name && !ISSLASH (*(first - 1)))
- --first;
+ char *p = xmalloc (length + 3);
+ p[0] = '.';
+ p[1] = '/';
+ memcpy (p + 2, base, length);
+ p[length + 2] = '\0';
+ return p;
}
- length = end_p - first;
- base = (char *) malloc (length + 1);
- if (base == 0)
- return 0;
+ /* Finally, copy the basename. */
+ return xstrndup (base, length);
+}
- memcpy (base, first, length);
- base[length] = '\0';
+/* Return the length of the basename NAME. Typically NAME is the
+ value returned by base_name or last_component. Act like strlen
+ (NAME), except omit all trailing slashes. */
- return base;
-}
+size_t
+base_len (char const *name)
+{
+ size_t len;
+ size_t prefix_len = FILE_SYSTEM_PREFIX_LEN (name);
-#ifdef TEST
-# include <assert.h>
-# include <stdlib.h>
+ for (len = strlen (name); 1 < len && ISSLASH (name[len - 1]); len--)
+ continue;
-# define CHECK(a,b) assert (strcmp (base_name_strip_trailing_slashes(a), b) \
- == 0)
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT && len == 1
+ && ISSLASH (name[0]) && ISSLASH (name[1]) && ! name[2])
+ return 2;
-int
-main ()
-{
- CHECK ("a", "a");
- CHECK ("ab", "ab");
- CHECK ("ab/c", "c");
- CHECK ("/ab/c", "c");
- CHECK ("/ab/c/", "c");
- CHECK ("/ab/c////", "c");
- CHECK ("/", "");
- CHECK ("////", "");
- CHECK ("////a", "a");
- CHECK ("//a//", "a");
- CHECK ("/a", "a");
- exit (0);
+ if (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE && prefix_len
+ && len == prefix_len && ISSLASH (name[prefix_len]))
+ return prefix_len + 1;
+
+ return len;
}
-#endif
projects / gnulib.git / blobdiff