From: H. Peter Anvin <hpa@zytor.com>
Date: Mon, 14 Jul 2008 19:44:21 +0000 (-0700)
Subject: keymap, font: use readc, so we can handle indeterminate file sizes
X-Git-Tag: syslinux-3.71-pre10^0
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b2bc8563baff2b7364f3aa49803319c5b5f77348;p=platform%2Fupstream%2Fsyslinux.git

keymap, font: use readc, so we can handle indeterminate file sizes

The keymap and font commands still assumed that we knew the file size,
which is no longer true.  Fix that by instead using "readc" and
checking the CF.
---

diff --git a/core/conio.inc b/core/conio.inc
index 6513f31..aa3fd0e 100644
--- a/core/conio.inc
+++ b/core/conio.inc
@@ -20,24 +20,30 @@
 ;;
 
 ;
-; loadkeys:	Load a LILO-style keymap; SI and EAX set by searchdir
+; loadkeys:	Load a LILO-style keymap; file is open on the top of the
+;		getc stack.
 ;
 		section .text
 
 loadkeys:
-		cmp eax,256			; Should be 256 bytes exactly
-		jne loadkeys_ret
-
-		mov bx,trackbuf
-		mov cx,1			; 1 cluster should be >= 256 bytes
-		call getfssec
+		mov cx,256
+		mov di,trackbuf
+		call readc
+		jc .done				; EOF already?
 
+		; Make sure we are at EOF now...
+		call getc
+		jnc .done			; We should be at EOF now!
+		
+		; It was okay, we can now move it into the KbdMap
 		mov si,trackbuf
 		mov di,KbdMap
 		mov cx,256 >> 2
 		rep movsd
 
-loadkeys_ret:	ret
+.done:
+		call close
+		ret
 
 ;
 ; get_msg_file: Load a text file and write its contents to the screen,
diff --git a/core/font.inc b/core/font.inc
index be9a365..a553f04 100644
--- a/core/font.inc
+++ b/core/font.inc
@@ -20,41 +20,49 @@
 
 ;
 ; loadfont:	Load a .psf font file and install it onto the VGA console
-;		(if we're not on a VGA screen then ignore.)  It is called with
-;		SI and EAX set by routine searchdir
+;		(if we're not on a VGA screen then ignore.)
+;		The font is on top of the getc stack.
 ;
+loadfont.err:	jmp close			; Tailcall the close routine
+
 loadfont:
-		; XXX: This can be 8K+4 bytes and the trackbuf is only
-		; guaranteed to be 8K in size...
-		mov bx,trackbuf
-		mov cx,[BufSafe]
-		call getfssec
+		mov di,trackbuf
+		mov cx,4
+		call readc			; Read header
+		jc .err
 
 		mov ax,[trackbuf]		; Magic number
 		cmp ax,0436h
-		jne lf_ret
+		jne .err
 
 		mov al,[trackbuf+2]		; File mode
 		cmp al,5			; Font modes 0-5 supported
-		ja lf_ret
+		ja .err
 
-		mov bh,byte [trackbuf+3]	; Height of font
+		xor bx,bx
+		mov bh,[trackbuf+3]		; Height of font
 		cmp bh,2			; VGA minimum
-		jb lf_ret
+		jb .err
 		cmp bh,32			; VGA maximum
-		ja lf_ret
+		ja .err
+
+		; Load the actual font
+		mov di,trackbuf
+		mov cx,bx			; Bytes = font height * 256
+		call readc
+		jc .err
+
+		call close
 
 		; Copy to font buffer
-		mov si,trackbuf+4		; Start of font data
+		mov si,trackbuf			; Start of font data
 		mov [VGAFontSize],bh
 		mov di,vgafontbuf
-		mov cx,(32*256) >> 2		; Maximum size
-		rep movsd
+		mov cx,bx
+		rep movsb
 
 		mov [UserFont], byte 1		; Set font flag
 
-		; Fall through to use_font
-
 ;
 ; use_font:
 ;	This routine activates whatever font happens to be in the
@@ -92,7 +100,7 @@ use_font:
 		shr ax,3			; 8 pixels/character
 		dec ax
 		mov [VidCols],al
-.lf_ret:	ret				; No need to call adjust_screen
+		ret				; No need to call adjust_screen
 
 .text:
 		mov cx,256
@@ -104,8 +112,6 @@ use_font:
 		mov ax,1103h			; Select page 0
 		int 10h
 
-lf_ret		equ use_font.lf_ret
-
 ;
 ; adjust_screen: Set the internal variables associated with the screen size.
 ;		This is a subroutine in case we're loading a custom font.
diff --git a/core/keywords.inc b/core/keywords.inc
index 65b657c..973d15b 100644
--- a/core/keywords.inc
+++ b/core/keywords.inc
@@ -52,9 +52,9 @@ keywd_table:
 		keyword initrd,		pc_filename,	InitRD
 		keyword default,	pc_default
 		keyword display,	pc_opencmd,	get_msg_file
-		keyword font,		pc_filecmd,	loadfont
+		keyword font,		pc_opencmd,	loadfont
 		keyword implicit,	pc_setint16,	AllowImplicit
-		keyword kbdmap,		pc_filecmd,	loadkeys
+		keyword kbdmap,		pc_opencmd,	loadkeys
 		keyword kernel,		pc_kernel,	VK_KERNEL
 		keyword linux,		pc_kernel,	VK_LINUX
 		keyword boot,		pc_kernel,	VK_BOOT