Add original unix v6

source/s1/chgrp.s

@@ -0,0 +1,106 @@
+/ chgrp -- change group
+
+
+	.globl	fopen, getc, mesg
+
+	mov	sp,r5
+	mov	(r5),r4
+	cmp	r4,$3
+	bge	1f
+	jsr	r5,mesg; <chown uid f1 ...\n\0>; .even
+1:
+	add	$4,r5
+	mov	(r5),r3
+	cmpb	(r3),$'0
+	blt	1f
+	cmpb	(r3),$'9
+	bgt	1f
+	jsr	r5,cvnum; geta
+	br	do
+1:
+	mov	$uids,r0
+	jsr	r5,fopen; ubuf
+	bec	1f
+	jsr	r5,mesg; <Can't open /etc/uids\n\0>; .even
+	sys	exit
+1:
+	mov	r3,r2
+2:
+	jsr	r5,getc; ubuf
+	bcc	3f
+who:
+	jsr	r5,mesg; <Who?\n\0>; .even
+	sys	exit
+3:
+	cmp	r0,$':
+	beq	3f
+	cmpb	(r2)+,r0
+	beq	2b
+2:
+	jsr	r5,getc; ubuf
+	bcs	who
+	cmp	r0,$'\n
+	bne	2b
+	br	1b
+3:
+	tstb	(r2)
+	bne	2b
+3:
+	jsr	r5,getc; ubuf
+	cmpb	r0,$':
+	bne	3b
+	jsr	r5,cvnum; getc
+do:
+	sub	$2,r4
+	swab	r1
+	mov	r1,0f+2
+	tst	(r5)+
+1:
+	mov	(r5),0f
+	mov	(r5)+,9f
+	sys	stat; 9:..; statb
+	movb	statb+7,0f+2
+	sys	chown; 0:..; 0
+	bec	2f
+	mov	0b,r0
+	mov	r0,0f
+	clr	0f+2
+3:
+	tstb	(r0)+
+	beq	3f
+	inc	0f+2
+	br	3b
+3:
+	mov	$1,r0
+	sys	write; 0:..; ..
+	jsr	r5,mesg; <?\n\0>; .even
+2:
+	dec	r4
+	bgt	1b
+	sys	exit
+
+cvnum:
+	clr	r1
+1:
+	jsr	r5,*(r5); ubuf
+	bcs	1f
+	sub	$'0,r0
+	cmp	r0,$9.
+	bhi	1f
+	mpy	$10.,r1
+	add	r0,r1
+	br	1b
+1:
+	tst	(r5)+
+	rts	r5
+
+geta:
+	movb	(r3)+,r0
+	tst	(r5)+
+	rts	r5
+
+uids:	</etc/group\0>
+
+	.bss
+statb:	.=.+36.
+ubuf:	.=.+518.