d 	.title	CONTROLC:  generalized CTRL-C interrupt handler
È 	.ident	/02/
,;
;    Roger Hauck
ô;    Smithsonian Institution
X;    Astrophysical Observatory
¼;    Cambridge, Mass. 02138
 ;    (617)495-7151 or (FTS)830-7151
„;    January, 1981
è;
L	.mcall	$iodef,$trnlog,$assign,$qiow_s,$getchn
°	$iodef
	$dcdef
x
Ü	.macro	.errsignal	?p1
@	blbs	r0,p1
¤	pushl	r0
	calls	#1,g^lib$signal
lp1:
Ð	.endm
4
˜	.psect	ABS,abs
ü;----DEFINE DISPLACEMENTS FOR STACK STORAGE
`	maxbuf=63
Ä	.=0
(
devnam:	.blkq				;descriptor for console device
Œ
lognam: .blkq				;descriptor for console log. name
ð
buffer:	.blkb	maxbuf			;buffer
Tstacklen:				;amt. of space to allocate on stack
¸
	.psect	kernel
€
ättname:	.ascic	/SYS$COMMAND/		;terminal name
H
¬	.entry	enable_ctrl_c,^m<r2,r3>
	movl	8(ap),r3		;r3->fixed storage
t	movl	4(ap),4(r3)		;save address of module to get the AST
Ø
<;form descriptors on the stack
 	subl2	#stacklen,sp		;allocate result buffer
	movl	sp,r2			;r2->stack space
h	movab	b^ttname,r1		;r0->counted string
Ì	movzbl	(r1)+,r0		;r0<length of string
0	movq	r0,lognam(r2)		;logical name descriptor
”	movl	#maxbuf,devnam(r2)	;device name descriptor
ø	movab	buffer(r2),devnam+4(r2)
\
À;----translate the name
$	$trnlog_s lognam=lognam(r2),-
ˆ		rsllen=devnam(r2),rslbuf=devnam(r2)
ì	.errsignal
P	cmpb	buffer(r2),#^x1b	;does name begin with escape?
´	bneq	10$			;no, skip
	subw	#4,devnam(r2)		;otherwise, subtract 4 from length
|	addl	#4,devnam+4(r2)		;add 4 to address
à10$:
D
¨;----assign a channel number
	$assign_s devnam=devnam(r2),chan=(r3) ;assign channel
p	.errsignal
Ô	addl2	#4,ap			;adjust ap for p2 of QIO below
8
œCKTERM:
 ;    check that device is a terminal
d;	setup stack for $GETCHN
È	clrq	-(sp)			;allocate 8-byte buffer & clear it
,	movl	sp,r2			;r2->buffer
	movl	sp,-(sp)		;-4(r2)-> buffer
ô	movl	#8,-(sp)		;-8(r2)<length of buffer
X	clrl	-(sp)			;-c(r2)<returned length, clear it
¼	$getchn_s chan=(r3),-
 		prilen=-12(r2),-
„		pribuf=-08(r2)
è					;ignore error condition
L		cmpb	#DC$_TERM,4(r2)	;is it a terminal
°		beql	30$		;yes, enable
		ret			;no, ignore request
x30$:
Ü	$qiow_s	chan=(r3),-
@		func=#io$_setmode!io$m_ctrlcast,-
¤		p1=b^here_on_ctrl_c,p2=4(ap)
 	.errsignal
l 	ret
Ð 
4!here_on_ctrl_c:
˜!	.word	^m<r2,r3>
ü!	movl	4(ap),r3		;3-> comm. block
`"	pushl	r3			;give address of communications block
Ä"	calls	#1,@4(r3)		;call application subroutine
(#	brb	CKTERM			;go re-enable
Œ#
ð#	.entry	disable_ctrl_c,0
T$	$dassgn_s	@4(ap)
¸$	.errsignal
%	ret
€%
ä%	.end