From 2953531913ff48f7574305f9a6942953f225a061 Mon Sep 17 00:00:00 2001
From: Renaud Fivet <renaud.fivet@gmail.com>
Date: Fri, 13 Feb 2015 15:33:21 +0800
Subject: [PATCH] Insure that mlwrite( "") as same effect as mlerase().

---
 Makefile  | 6 +++---
 buffer.c  | 6 +++---
 display.c | 4 ++--
 mlout.c   | 2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/Makefile b/Makefile
index d555f94..ea5408a 100644
--- a/Makefile
+++ b/Makefile
@@ -135,7 +135,7 @@ bindable.o: bindable.c bindable.h defines.h buffer.h crypt.h line.h \
  retcode.h utf8.h display.h estruct.h file.h input.h bind.h lock.h \
  mlout.h terminal.h
 buffer.o: buffer.c buffer.h crypt.h line.h retcode.h utf8.h defines.h \
- display.h estruct.h file.h input.h bind.h window.h
+ estruct.h file.h input.h bind.h mlout.h window.h
 crypt.o: crypt.c crypt.h
 display.o: display.c display.h estruct.h buffer.h crypt.h line.h \
  retcode.h utf8.h input.h bind.h termio.h terminal.h defines.h version.h \
@@ -164,8 +164,8 @@ line.o: line.c line.h retcode.h utf8.h buffer.h crypt.h estruct.h mlout.h \
  window.h defines.h
 lock.o: lock.c estruct.h lock.h
 main.o: main.c estruct.h basic.h bind.h bindable.h buffer.h crypt.h \
- line.h retcode.h utf8.h display.h eval.h execute.h file.h input.h \
- mlout.h lock.h random.h search.h terminal.h defines.h termio.h version.h \
+ line.h retcode.h utf8.h display.h eval.h execute.h file.h input.h lock.h \
+ mlout.h random.h search.h terminal.h defines.h termio.h version.h \
  window.h
 mingw32.o: mingw32.c
 mlout.o: mlout.c mlout.h
diff --git a/buffer.c b/buffer.c
index 625e1b7..341e6d4 100644
--- a/buffer.c
+++ b/buffer.c
@@ -17,10 +17,10 @@
 #include <string.h>
 
 #include "defines.h"
-#include "display.h"
 #include "estruct.h"
 #include "file.h"
 #include "input.h"
+#include "mlout.h"
 #include "window.h"
 
 
@@ -189,7 +189,7 @@ int zotbuf(struct buffer *bp)
 	int s;
 
 	if (bp->b_nwnd != 0) {	/* Error if on screen.  */
-		mlwrite("Buffer is being displayed");
+		mloutstr("Buffer is being displayed");
 		return FALSE;
 	}
 	if ((s = bclear(bp)) != TRUE)	/* Blow text away.      */
@@ -238,7 +238,7 @@ int namebuffer(int f, int n)
 
 	strcpy(curbp->b_bname, bufn);	/* copy buffer name to structure */
 	curwp->w_flag |= WFMODE;	/* make mode line replot */
-	mlerase();
+	mloutstr( "") ; /* erase message line */
 	return TRUE;
 }
 
diff --git a/display.c b/display.c
index 69e0e13..18bc062 100644
--- a/display.c
+++ b/display.c
@@ -1370,6 +1370,7 @@ void mlwrite(const char *fmt, ...)
 	else
 		movecursor( term.t_nrow, 0) ;
 
+	mpresf = *fmt ? TRUE : FALSE ;	/* flag if line has content or not */
 	va_start(ap, fmt);
 	while ((c = *fmt++) != 0) {
 		if (c != '%')
@@ -1417,7 +1418,6 @@ void mlwrite(const char *fmt, ...)
 		TTeeol() ;
 
 	TTflush();
-	mpresf = TRUE;
 }
 
 /*
@@ -1432,7 +1432,7 @@ void mlforce( char *s) {
 
 	oldcmd = discmd;	/* save the discmd value */
 	discmd = TRUE;		/* and turn display on */
-	mlwrite( "%s", s) ;	/* write the string out */
+	mlwrite( (*s) ? "%s" : "", s) ;	/* write the string out or erase line */
 	discmd = oldcmd;	/* and restore the original setting */
 }
 
diff --git a/mlout.c b/mlout.c
index 73f6eb2..3c7ebd0 100644
--- a/mlout.c
+++ b/mlout.c
@@ -9,7 +9,7 @@ static void mloutdump( const char *buf, ...) {
 void (*mloutfmt)( const char *, ...) = mloutdump ;
 
 void mloutstr( const char *str) {
-	mloutfmt( "%s", str) ;
+	mloutfmt( (*str) ? "%s" : "", str) ;
 }
 
 /* end of mlout.c */