+ 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)
+ {
+ base = p;
+ saw_slash = false;
+ }
+ }
+
+ return (char *) base;
+}
+
+
+/* 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;