Add DHCP option to set PXELINUX reset timeout.syslinux-1.62-pre1

2 files changed, 31 insertions, 3 deletions

diff --git a/pxelinux.asm b/pxelinux.asm
index c7f6d1c4..74ca65f7 100644
--- a/pxelinux.asm
+++ b/pxelinux.asm
@@ -349,6 +349,7 @@ KernelSize	resd 1			; Size of kernel (bytes)
 Stack		resd 1			; Pointer to reset stack
 PXEEntry	resd 1			; !PXE API entry point
 SavedSSSP	resd 1			; Our SS:SP while running a COMBOOT image
+RebootTime	resd 1			; Reboot timeout, if set by option
 FBytes		equ $			; Used by open/getc
 FBytes1		resw 1
 FBytes2		resw 1
@@ -2604,15 +2605,22 @@ kaboom:
 		call getchar
 		jmp short .drain
 .drained:
+		mov edi,[RebootTime]
+		mov al,[DHCPMagic]
+		and al,09h		; Magic+Timeout
+		cmp al,09h
+		jne .not_set
+		mov edi,REBOOT_TIME
+.not_set:
 		mov cx,18
 .wait1:		push cx
-		mov cx,REBOOT_TIME
+		mov ecx,edi
 .wait2:		mov dx,[BIOS_timer]
 .wait3:		call pollchar
 		jnz .keypress
 		cmp dx,[BIOS_timer]
 		je .wait3
-		loop .wait2
+		a32 loop .wait2		; a32 means use ecx as counter
 		mov al,'.'
 		call writechr
 		pop cx
@@ -4270,6 +4278,19 @@ parse_dhcp_options:
 		jmp short .copyoption
 	
 .not_pl_prefix:
+		cmp dl,179	; PXELINUX REBOOTTIME option
+		jne .not_pl_timeout
+		cmp al,4
+		jne .opt_done
+		mov edx,[si]
+		xchg dl,dh	; Convert to host byte order
+		rol edx,16
+		xchg dl,dh
+		mov [RebootTime],edx
+		or byte [DHCPMagic], byte 8	; Got RebootTime
+		; jmp short .opt_done
+
+.not_pl_timeout
 		; Unknown option.  Skip to the next one.
 .opt_done:
 		add si,ax
diff --git a/pxelinux.doc b/pxelinux.doc
index 9e1a7d26..96e95cbf 100644
--- a/pxelinux.doc
+++ b/pxelinux.doc
@@ -248,14 +248,20 @@ Option 178	pxelinux.pathprefix
 	  needs to end in whatever character the TFTP server OS uses
 	  as a pathname separator, e.g. slash (/) for Unix.
 
+Option 179	pxelinux.reboottime
+	- Specifies, in seconds, the time to wait before reboot in the
+	  event of TFTP failure.  0 means wait "forever" (in reality,
+	  it waits approximately 136 years.)
+
 ISC dhcp 3.0 supports a rather nice syntax for specifying custom
 options; you can use the following syntax in dhcpd.conf if you are
 running this version of dhcpd:
 
 	option space pxelinux;
-	option pxelinux.magic code 176 = string;
+	option pxelinux.magic      code 176 = string;
 	option pxelinux.configfile code 177 = text;
 	option pxelinux.pathprefix code 178 = text;
+	option pxelinux.reboottime code 179 = unsigned integer 32;
 
 Then, inside your PXELINUX-booting group or class (whereever you have
 the PXELINUX-related options, such as the filename option), you can
@@ -265,6 +271,7 @@ add, for example:
 	option pxelinux.magic f1:00:74:7e;
 	option pxelinux.configfile "configs/common";
 	option pxelinux.pathprefix "/tftpboot/pxelinux/files/";
+	option pxelinux.reboottime 30;
 	filename "/tftpboot/pxelinux/pxelinux.bin";
 
 Note that the configfile is relative to the pathprefix: this will look