New CONSOLE directive to enable/disable the video console.syslinux-3.02-pre3

8 files changed, 30 insertions, 2 deletions

diff --git a/NEWS b/NEWS
index ba23f6f3..bb8180bc 100644
--- a/NEWS
+++ b/NEWS
@@ -13,6 +13,8 @@ Changes in 3.02:
 	* Simple menu system: minor aestetic improvements, and try to
 	  work better over a serial console (speed, and readability on
 	  monochrome terminal emulators.)
+	* New CONSOLE directive to control output on the video console
+	  (useful for dealing with some broken serial-forwarding BIOSes.)
 
 Changes in 3.01:
 	* EXTLINUX, SYSLINUX: Fix compile errors on some systems.
diff --git a/conio.inc b/conio.inc
index b652eb41..7af5ebe1 100644
--- a/conio.inc
+++ b/conio.inc
@@ -1,7 +1,7 @@
 ;; $Id$
 ;; -----------------------------------------------------------------------
 ;;   
-;;   Copyright 1994-2004 H. Peter Anvin - All Rights Reserved
+;;   Copyright 1994-2005 H. Peter Anvin - All Rights Reserved
 ;;
 ;;   This program is free software; you can redistribute it and/or modify
 ;;   it under the terms of the GNU General Public License as published by
@@ -111,6 +111,8 @@ msg_putchar:                                    ; Normal character
 msg_normal:	call write_serial_displaymask	; Write to serial port
 		test [DisplayMask],cl
 		jz msg_ignore			; Not screen
+		test byte [DisplayCon],01h
+		jz msg_ignore
                 mov bl,[TextAttribute]
 		mov bh,[BIOS_page]
                 mov ah,09h                      ; Write character/attribute
@@ -374,6 +376,9 @@ debug_tracer:	pushad
 %endif	; DEBUG_TRACERS
 
 		section .data
+		; This is a word to pc_setint16 can set it
+DisplayCon	dw 01h			; Console display enabled
+
 ScrollAttribute	db 07h			; Grey on white (normal text color)
 
 		section .bss
diff --git a/extlinux.asm b/extlinux.asm
index 9577d310..78496bd5 100644
--- a/extlinux.asm
+++ b/extlinux.asm
@@ -6,7 +6,7 @@
 ;
 ;  A program to boot Linux kernels off an ext2/ext3 filesystem.
 ;
-;   Copyright (C) 1994-2004  H. Peter Anvin
+;   Copyright (C) 1994-2005  H. Peter Anvin
 ;
 ;  This program is free software; you can redistribute it and/or modify
 ;  it under the terms of the GNU General Public License as published by
@@ -1151,12 +1151,15 @@ unmangle_name:	call strcpy
 writechr:
 		call write_serial	; write to serial port if needed
 		pushfd
+		test byte [cs:DisplayCon],01h
+		jz .nothing
 		pushad
 		mov ah,0Eh
 		mov bl,07h		; attribute
 		mov bh,[cs:BIOS_page]	; current page
 		int 10h
 		popad
+.nothing:
 		popfd
 		ret
 
diff --git a/keywords b/keywords
index 046a2f29..155a4e19 100644
--- a/keywords
+++ b/keywords
@@ -13,6 +13,7 @@ localboot
 prompt
 say
 serial
+console
 timeout
 allowoptions
 ontimeout
diff --git a/keywords.inc b/keywords.inc
index a4b665e1..6f68554e 100644
--- a/keywords.inc
+++ b/keywords.inc
@@ -57,6 +57,7 @@ keywd_table:
 		keyword prompt,    pc_setint16, ForcePrompt
 		keyword say,       pc_say
 		keyword serial,    pc_serial
+		keyword console,   pc_setint16,	DisplayCon
 		keyword timeout,   pc_timeout
 		keyword ontimeout, pc_ontimeout
 		keyword onerror,   pc_onerror
diff --git a/ldlinux.asm b/ldlinux.asm
index 71428fb9..ceb079fe 100644
--- a/ldlinux.asm
+++ b/ldlinux.asm
@@ -1055,12 +1055,15 @@ searchdir:
 writechr:
 		call write_serial	; write to serial port if needed
 		pushfd
+		test byte [cs:DisplayCon], 01h
+		jz .nothing
 		pushad
 		mov ah,0Eh
 		mov bl,07h		; attribute
 		mov bh,[cs:BIOS_page]	; current page
 		int 10h
 		popad
+.nothing:
 		popfd
 		ret
 
diff --git a/rawcon.inc b/rawcon.inc
index 87e69fa8..9f02e4f2 100644
--- a/rawcon.inc
+++ b/rawcon.inc
@@ -13,6 +13,9 @@ writechr:
 		pop ds
 		call write_serial	; write to serial port if needed
 		pushfd
+		test byte [DisplayCon],01h	; Write to screen?
+		jz .nothing
+
 		pushad
 		mov bh,[BIOS_page]
 		push ax
@@ -43,6 +46,7 @@ writechr:
 		mov ah,02h		; Set cursor position
 		int 10h			
 .ret:		popad
+.nothing:
 		popfd
 		pop ds
 		ret
diff --git a/syslinux.doc b/syslinux.doc
index 6373d67c..0092f887 100644
--- a/syslinux.doc
+++ b/syslinux.doc
@@ -288,6 +288,15 @@ SERIAL port [[baudrate] flowcontrol]
 	ports detected by the BIOS.  They may or may not correspond to
 	the legacy port values 0x3F8, 0x2F8, 0x3E8, 0x2E8.
 
+CONSOLE flag_val
+	If flag_val is 0, disable output to the normal video console.
+	If flag_val is 1, enable output to the video console (this is
+	the default.)
+
+	Some BIOSes try to forward this to the serial console and
+	sometimes make a total mess thereof, so this option lets you
+	disable the video console on these systems.
+
 FONT filename
 	Load a font in .psf format before displaying any output
 	(except the copyright line, which is output as ldlinux.sys