patch 9.1.1122: too many strlen() calls in findfile.c

Problem:  too many strlen() calls in findfile.c
Solution: refactor findfile.c and remove calls to strlen()
          (John Marriott)

closes: #16595

Signed-off-by: John Marriott <basilisk@internode.on.net>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/proto/findfile.pro b/src/proto/findfile.pro
index 1c28221..628042c 100644
--- a/src/proto/findfile.pro
+++ b/src/proto/findfile.pro
@@ -1,5 +1,5 @@
 /* findfile.c */
-void *vim_findfile_init(char_u *path, char_u *filename, char_u *stopdirs, int level, int free_visited, int find_what, void *search_ctx_arg, int tagfile, char_u *rel_fname);
+void *vim_findfile_init(char_u *path, char_u *filename, size_t filenamelen, char_u *stopdirs, int level, int free_visited, int find_what, void *search_ctx_arg, int tagfile, char_u *rel_fname);
 char_u *vim_findfile_stopdir(char_u *buf);
 void vim_findfile_cleanup(void *ctx);
 char_u *vim_findfile(void *search_ctx_arg);
@@ -14,6 +14,6 @@
 int vim_ispathlistsep(int c);
 void uniquefy_paths(garray_T *gap, char_u *pattern, char_u *path_option);
 int expand_in_path(garray_T *gap, char_u *pattern, int flags);
-void simplify_filename(char_u *filename);
+size_t simplify_filename(char_u *filename);
 void f_simplify(typval_T *argvars, typval_T *rettv);
 /* vim: set ft=c : */