diff --git a/src/proto/charset.pro b/src/proto/charset.pro
index df09710..97aa71e 100644
--- a/src/proto/charset.pro
+++ b/src/proto/charset.pro
@@ -17,7 +17,7 @@
 int chartabsize(char_u *p, colnr_T col);
 int linetabsize(char_u *s);
 int linetabsize_col(int startcol, char_u *s);
-int win_linetabsize(win_T *wp, char_u *line, colnr_T len);
+int win_linetabsize(win_T *wp, linenr_T lnum, char_u *line, colnr_T len);
 int vim_isIDc(int c);
 int vim_isNormalIDc(int c);
 int vim_iswordc(int c);
@@ -28,9 +28,11 @@
 int vim_isfilec_or_wc(int c);
 int vim_isprintc(int c);
 int vim_isprintc_strict(int c);
-int lbr_chartabsize(char_u *line, unsigned char *s, colnr_T col);
-int lbr_chartabsize_adv(char_u *line, char_u **s, colnr_T col);
-int win_lbr_chartabsize(win_T *wp, char_u *line, char_u *s, colnr_T col, int *headp);
+void init_chartabsize_arg(chartabsize_T *cts, win_T *wp, linenr_T lnum, colnr_T col, char_u *line, char_u *ptr);
+void clear_chartabsize_arg(chartabsize_T *cts);
+int lbr_chartabsize(chartabsize_T *cts);
+int lbr_chartabsize_adv(chartabsize_T *cts);
+int win_lbr_chartabsize(chartabsize_T *cts, int *headp);
 void getvcol(win_T *wp, pos_T *pos, colnr_T *start, colnr_T *cursor, colnr_T *end);
 colnr_T getvcol_nolist(pos_T *posp);
 void getvvcol(win_T *wp, pos_T *pos, colnr_T *start, colnr_T *cursor, colnr_T *end);