- initial import for OCR of section e12 -- init.s

notes/notes.txt

@@ -56,7 +56,7 @@ e11-01 to e11-07 (7) - sh
    reviewed:
 e12-01 to e12-04 (4) - init 
    we have a binary for init already
-   assigned:
+   assigned: tim newsham, complete
    reviewed:
 
 
@@ -272,3 +272,9 @@ e11-04
    - Line 8 has what resembles a "|", not sure if this is a screwup or
      not. Preserved, and assuming it's a "|".
    - line 21/22: I have no idea.
+---------------------
+e12-01
+   - "rko5" in comments left as is (vs "rk05")
+   - acceped overwritten "ttyx" over the obscured original "xxxx"
+
+

pages/e12-01

@@ -0,0 +1,55 @@
+/ init -- process control initialization
+
+mount = 21.
+
+	sys	intr; 0 / turn off interrupts
+	sys 	quit; 0
+	cmp	csw,$73700 / single user?
+	bne	if / no
+help:
+	clr	r0 / yes
+	sys	close / close current read
+	mov	$1,r0 / and write
+	sys	close / files
+	sys	open; ctty; 0 / open control tty
+	sys	open; ctty; 1 / for read and write
+	sys	exec; shell; shellp / execute shell
+	br	help / keep trying
+1:
+	mov	$'0,r1 / prepare to change
+1 :
+	movb	r1,tapx+8 / mode of dec tape drive x, where
+	sys	chmod; tapx; 17 / x=0 to 7, to read/write by owner or
+	inc	r1 / non-owner mode
+	cmp	r1,$'8 / finished?
+	blo	1b / no
+	sys	mount; rk0; usr / yes, root file on mounted rko5
+				/ disk ls /usr
+	sys	creat; utmp; 16 / truncate /tmp/utmp
+	sys	close / close it
+	movb	$'x,zero+8. / put identifier in output buffer
+	jsr	pc.wtmprec / go to write accting info
+	mov	$itab,r1 / address of table to r1
+
+/ create shell processes
+
+1:
+	mov	(r1)+,r0 / 'x, x=0, 1... to r0
+	beq	1f / branch if table end
+	movb	r0,ttyx+8 / put symbol in ttyx
+	jsr	pc,dfork / go to make new init for this ttyx
+	mov	r0,(r1)+ / save child id in word offer '0, '1,...etc.
+	br	1b / set up next child
+
+/ wait for process to die
+
+1:
+	sys	wait / wait for user to terminate process
+	mov	$itab,r1 / initialize for search
+
+/ search for process id
+
+2:
+	tst	(r1)+ / bump r1 to child id location
+	beq	1b / ? something silly
+	cmp	r0,(r1)+ / which process has terminated

pages/e12-02

@@ -0,0 +1,56 @@
+	bne	2b / not this one
+
+/ take name out of utmp
+
+	sub	$4, r1 / process is found, point x' to 'x
+		       / for it
+	mov	r1,-(sp) / save address on stack
+	mov	(r1),r1 / move 'x to r1
+	sub	$'0,r1 / remove zone bits from character
+	asl	r1 / generate proper
+	asl	r1 / offset
+	asl	r1 / for
+	asl	r1 / seek
+	mov	r1,0f / move it to offset loc for seek
+	mov	$zero,r1
+2:
+	clr	(r1)+ / ccear-
+	cmp	r1,$zero+16. / output buffer
+	blo	2b / area
+	sys	open; utmp; 1 / open file for writing
+	bes	2f / if can't open, create user anyway
+	mov	r0,r1 / save file desc
+	sys	seek; 0:..; 0 / move to proper pointer position
+	mov	r1,r0 / not required
+	sys	write; zero; 16. / zero this position in
+	mov	r1,r0 / restore file descriptor
+	sys	close / close file
+
+/ re-create user process
+
+2:
+	mov	(sp)+,r1 / restore 'x to r1
+	mov	(r1)+,r0 / move it to r0
+	movb	r0,ttyx+8 / get correct ttyx
+	movb	r0,zero+8 / move identifier to output buffer
+	jsr	pc,wtmprec / go to write accting into
+	jsr	pc,dfork / fork
+	mov	r0,(r1)+ / save id of child
+	br	1b / go to wait for next process end
+
+dfork:
+	mov	r1,r2
+	sub	$itab+2,r2 / left over
+	asl	r2 / from previous
+	asl	r2 / version of code
+	mov	r2,offset
+	sys	fork
+		br 1f / to new copy of init
+	bes	dfork / try again
+	rts	pc / return
+1 :
+	sys	quit; 0 / new init turns off
+	sys	intr; 0 / interrupts
+	sys	chown; ttyx; 0 / change owner to super user
+	sys	chmod; ttyx; 15 / changemode to read/write owner,
+				/ write non-owner

pages/e12-03

@@ -0,0 +1,55 @@
+	sys	open; ttyx; 0 / open this ttyx for reading
+			      / and wait until someone calls
+	bes	help1 / branch if trouble
+	sys	open; ttyx; 1 / open this ttyx for writing after
+			      / user call
+	bes	help1 / branch if trouble
+	sys	exec; getty; gettyp / getty types <login> and
+				    / executes login which logs user
+				    / in and executes sh-
+	sys	exit / HELP!
+
+help1:
+	jmp	help / trouble
+
+wtmprec:
+	sys	time / get time
+	mov	ac,zero+10. / more to output
+	mov	mq,zero+12. / buffer
+	sys	open; wtmp; 1 / open accounting file
+	bes	2f
+	mov	r0,r2 / save file descriptor
+	sys	seek; 0; 2 / move pointer to end of file
+	mov	r2,r0 / not required
+	sys	write; zero; 16. / write accting info
+	mov	r2,r0 / restore file descriptor
+	sys	close / close file
+2:
+	rts	pc
+
+ctty:	</dev/tty\0>
+shell:	</bin/sh\0>
+shellm:	<-\0>
+tapx:	</dev/tapx\0>
+rk0:	</dev/rk0\0>
+utmp:	</tmp/utmp\0>
+wtmp:	</tmp/wtmp\0>
+ttyx:	</dev/ttyx\0>
+getty:	</etc/qetty\0>
+usr:	</usr\0)
+	.even
+
+shellp:	shellm
+	0
+gettyp:	getty
+	0
+itab:
+	'0; ..
+	'1; ..
+	'2; ..
+	'3; ..
+	'4; ..
+	'5; ..
+	'6; ..
+	'7; ..
+	0

pages/e12-04

@@ -0,0 +1,3 @@
+
+offset:	.=.+2
+zero:	.=.+8; .=.+6; .=.+2

tools/rebuild

@@ -17,8 +17,8 @@ rebuild() {
     r u8 e08
     r u9 e09
     r ux e10
-    #r sh e11
-    #r ini e12
+    r sh e11
+    r init e12
 }
 
 p() { echo ' ' $1; patch -s -p1 <../patches/$1.patch; }