More splits from "tuxpaint.c":

+ "debug.h": Defines whether debugging printf() calls should be enabled.
  + "dirwalk.c/h": Callback functions for recursive directory traversal.
  + "fonts.c/h": Font loading/grouping/discarding variables and functions.
  + "get_fname.c/h": Functions for constructing preferred file paths.

src/dirwalk.h

@@ -0,0 +1,33 @@
+/*
+  dirwalk.h
+*/
+
+#ifndef DIRWALK_H
+#define DIRWALK_H
+
+#include "SDL.h"
+
+#include "compiler.h"
+
+/////////////////////////////// directory tree walking /////////////////////
+
+#define TP_FTW_UNKNOWN 1
+#define TP_FTW_DIRECTORY 2
+#define TP_FTW_NORMAL 0
+
+#define TP_FTW_PATHSIZE 400
+
+typedef struct tp_ftw_str {
+  char *str;
+  unsigned char len;
+//  unsigned char is_rsrc;
+} tp_ftw_str;
+
+
+void loadfont_callback(SDL_Surface * screen, const char *restrict const dir, unsigned dirlen, tp_ftw_str *files, unsigned i);
+int compare_ftw_str(const void *v1, const void *v2);
+void tp_ftw(SDL_Surface * screen, char *restrict const dir, unsigned dirlen, int rsrc,
+  void (*fn)(SDL_Surface * screen, const char *restrict const dir, unsigned dirlen, tp_ftw_str *files, unsigned count));
+
+#endif
+