-/* basename.c -- return the last element in a path
+/* basename.c -- return the last element in a file name
- Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004 Free
+ Copyright (C) 1990, 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006 Free
Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ 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.
+ 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
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. */
+ along with this program. If not, see <http://www.gnu.org/licenses/>. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
#include "dirname.h"
-#include <string.h>
-/* 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.
+#include <string.h>
+#include "xalloc.h"
+#include "xstrndup.h"
- Return the address of the last file name component of NAME. If
- NAME has no file name components because it is all slashes, return
- NAME if it is empty, the address of its last slash otherwise. */
+/* 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 (char const *name)
+last_component (char const *name)
{
char const *base = name + FILE_SYSTEM_PREFIX_LEN (name);
char const *p;
+ bool saw_slash = false;
+
+ while (ISSLASH (*base))
+ base++;
for (p = base; *p; p++)
{
if (ISSLASH (*p))
+ saw_slash = true;
+ else if (saw_slash)
{
- /* Treat multiple adjacent slashes like a single slash. */
- do p++;
- while (ISSLASH (*p));
-
- /* If the file name ends in slash, use the trailing slash as
- the basename if no non-slashes have been found. */
- if (! *p)
- {
- if (ISSLASH (*base))
- base = p - 1;
- break;
- }
-
- /* *P is a non-slash preceded by a slash. */
base = p;
+ saw_slash = false;
}
}
return (char *) base;
}
-/* Return the length of of the basename NAME. Typically NAME is the
- value returned by base_name. Act like strlen (NAME), except omit
- redundant trailing slashes. */
+
+/* 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 (char const *name)
+{
+ 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))
+ {
+ char *p = xmalloc (length + 3);
+ p[0] = '.';
+ p[1] = '/';
+ memcpy (p + 2, base, length);
+ p[length + 2] = '\0';
+ return p;
+ }
+
+ /* Finally, copy the basename. */
+ return xstrndup (base, length);
+}
+
+/* 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. */
size_t
base_len (char const *name)
{
size_t len;
+ size_t prefix_len = FILE_SYSTEM_PREFIX_LEN (name);
for (len = strlen (name); 1 < len && ISSLASH (name[len - 1]); len--)
continue;
+ if (DOUBLE_SLASH_IS_DISTINCT_ROOT && len == 1
+ && ISSLASH (name[0]) && ISSLASH (name[1]) && ! name[2])
+ return 2;
+
+ if (FILE_SYSTEM_DRIVE_PREFIX_CAN_BE_RELATIVE && prefix_len
+ && len == prefix_len && ISSLASH (name[prefix_len]))
+ return prefix_len + 1;
+
return len;
}
projects / gnulib.git / blobdiff