extern const char *setup_git_directory(void);
extern char *prefix_path(const char *prefix, int len, const char *path);
extern char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
-extern const char *prefix_filename(const char *prefix, int len, const char *path);
+
+/*
+ * Concatenate "prefix" (if len is non-zero) and "path", with no
+ * connecting characters (so "prefix" should end with a "/").
+ * Unlike prefix_path, this should be used if the named file does
+ * not have to interact with index entry; i.e. name of a random file
+ * on the filesystem.
+ *
+ * The return value is always a newly allocated string (even if the
+ * prefix was empty).
+ */
+extern char *prefix_filename(const char *prefix, const char *path);
+
extern int check_filename(const char *prefix, const char *name);
extern void verify_filename(const char *prefix,
const char *name,
*/
extern char *xdg_config_home(const char *filename);
+/**
+ * Return a newly allocated string with the evaluation of
+ * "$XDG_CACHE_HOME/git/$filename" if $XDG_CACHE_HOME is non-empty, otherwise
+ * "$HOME/.cache/git/$filename". Return NULL upon error.
+ */
+extern char *xdg_cache_home(const char *filename);
+
/* object replacement */
#define LOOKUP_REPLACE_OBJECT 1
#define LOOKUP_UNKNOWN_OBJECT 2