Add an API call to query the configuration file name

6 files changed, 40 insertions, 14 deletions

diff --git a/NEWS b/NEWS
index 50bc9577..72845ffd 100644
--- a/NEWS
+++ b/NEWS
@@ -2,6 +2,9 @@ Starting with 1.47, changes marked with SYSLINUX/PXELINUX/ISOLINUX
 apply to that specific program only; other changes apply to all of
 them.
 
+Changes in 2.11:
+	* ALL: Add an API call to get the configuration file name.
+
 Changes in 2.10:
 	* MEMDISK: Handle images compressed with zip as well as with
 	  gzip.  Some Windows-based image tools apparently generate
diff --git a/comboot.doc b/comboot.doc
index 48e7f8f3..cab8c936 100644
--- a/comboot.doc
+++ b/comboot.doc
@@ -247,7 +247,7 @@ AX=0003h	Run command
 
 	Input:	AX	0003h
 		ES:BX	null-terminated command string
-	Output:	None
+	Output:	Does not return
 
 	This API call terminates the program and executes the command
 	string as if the user had entered it at the SYSLINUX command
@@ -257,7 +257,7 @@ AX=0003h	Run command
 AX=0004h	Run default command
 
 	Input:	AX	0004h
-	Output:	None
+	Output:	Does not return
 
 	This API call terminates the program and executes the default
 	command string as if the user had pressed Enter alone on the
@@ -424,7 +424,7 @@ AX=000Bh	Get Serial Console Configuration
 AX=000Ch	Perform final cleanup
 	Input:	AX	000Ch
 		DX	derivative-specific flags (0000h = clean up all)
-	Output:	None
+	Output:	Does not return
 
 	This routine performs any "final cleanup" the boot loader
 	would normally perform before loading a kernel, such as
@@ -461,7 +461,7 @@ AX=000Dh	Cleanup and replace bootstrap code
 		EBX(!)	initial value of EDX after bootstrap
 		ESI	initial value of ESI after bootstrap
 		DS	initial value of DS after bootstrap
-	Output:	None
+	Output:	Does not return
 
 	This routine performs final cleanup, then takes a piece of
 	code, copies it over the primary bootstrap at address 7C00h,
@@ -476,3 +476,12 @@ AX=000Dh	Cleanup and replace bootstrap code
 	For PXELINUX, if the PXE stack is not unloaded, all registers
 	(except DS, ESI and EDX) and the stack will be set up as they
 	were set up by the PXE ROM.
+
+
+AX=000Eh	Get configuration file name
+	Input:	AX	0000Eh
+	Output:	ES:BX	null-terminated file name string
+
+	Returns the name of the configuration file.  Note that it is
+	possible that the configuration file doesn't actually exist.
+
diff --git a/comboot.inc b/comboot.inc
index 3318a311..3a8f377b 100644
--- a/comboot.inc
+++ b/comboot.inc
@@ -551,6 +551,16 @@ comapi_chainboot:
 		push P_ECX
 		jmp replace_bootstrap
 
+
+;
+; INT 22h AX=000Eh	Get configuration file name
+;
+comapi_configfile:
+		mov P_ES,cs
+		mov P_BX,ConfigName
+		clc
+		ret
+
 ;
 ; This stuff should really be in the data section...
 ;
@@ -588,6 +598,7 @@ int22_table:
 		dw comapi_serialcfg		; 000B get serial port config
 		dw comapi_cleanup		; 000C perform final cleanup
 		dw comapi_chainboot		; 000D clean up then bootstrap
+		dw comapi_configfile		; 000E get name of config file
 int22_count	equ ($-int22_table)/2
 
 APIKeyWait	db 0
diff --git a/isolinux.asm b/isolinux.asm
index 04d829ce..d1d250b2 100644
--- a/isolinux.asm
+++ b/isolinux.asm
@@ -1680,6 +1680,7 @@ default_str	db 'default', 0
 default_len	equ ($-default_str)
 boot_dir	db '/boot'			; /boot/isolinux
 isolinux_dir	db '/isolinux', 0
+ConfigName	equ $
 isolinux_cfg	db 'isolinux.cfg', 0
 err_disk_image	db 'Cannot load disk image (invalid file)?', CR, LF, 0
 
diff --git a/ldlinux.asm b/ldlinux.asm
index ad367100..b58211b0 100644
--- a/ldlinux.asm
+++ b/ldlinux.asm
@@ -1412,7 +1412,8 @@ aborted_msg	db ' aborted.'			; Fall through to crlf_msg!
 crlf_msg	db CR, LF
 null_msg	db 0
 crff_msg	db CR, FF, 0
-syslinux_cfg	db 'SYSLINUXCFG'
+syslinux_cfg	db 'SYSLINUXCFG'		; Mangled form
+ConfigName	db 'syslinux.cfg',0		; Unmangled form
 %if IS_MDSLINUX
 manifest	db 'MANIFEST   '
 %endif
diff --git a/pxelinux.asm b/pxelinux.asm
index 3b8a818f..58ae7e34 100644
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -817,10 +817,7 @@ prefix:		test byte [DHCPMagic], 04h	; Did we get a path prefix option
 ; Load configuration file
 ;
 find_config:
-		mov di,trackbuf
-		mov si,cfgprefix
-		mov cx,cfgprefix_len
-		rep movsb
+
 ;
 ; Begin looking for configuration file
 ;
@@ -829,7 +826,6 @@ config_scan:
 		jz .no_option
 
 		; We got a DHCP option, try it first
-		push di
 		mov si,trying_msg
 		call writestr
 		mov di,ConfigName
@@ -837,18 +833,23 @@ config_scan:
 		call writestr
 		call crlf
 		call open
-		pop di
 		jnz .success
 
-.no_option:	; Have to guess config file name
+.no_option:
+		mov di,ConfigName
+		mov si,cfgprefix
+		mov cx,cfgprefix_len
+		rep movsb
+
 		; Try loading by MAC address
+		; Have to guess config file name
 		push di
 		mov si,MACStr
 		mov cx,(3*17+1)/2
 		rep movsw
 		mov si,trying_msg
 		call writestr
-		mov di,trackbuf
+		mov di,ConfigName
 		mov si,di
 		call writestr
 		call crlf
@@ -887,7 +888,7 @@ config_scan:
 .not_default:	pusha
 		mov si,trying_msg
 		call writestr
-		mov di,trackbuf
+		mov di,ConfigName
 		mov si,di
 		call writestr
 		call crlf