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; UPD ID= 472 on 6/15/82 at 10:44 AM by NIXON                           
TITLE	COBFUN FOR COBOL OTS
SUBTTL	D. M. NIXON/ACK/DZN/DSB

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;THIS SOFTWARE IS FURNISHED UNDER A LICENSE AND MAY ONLY BE USED
;  OR COPIED IN ACCORDANCE WITH THE TERMS OF SUCH LICENSE.

COPYRIGHT (C) 1977, 1983, 1984 BY DIGITAL EQUIPMENT CORPORATION


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TWOSEG	400000
	.COPYRIGHT		;Put standard copyright statement in REL file
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SUBTTL	REVISION HISTORY

;INTERN	COBOL	WHO	WHAT
;001		DMN	Creation
;002		ACK	Modifications to allow overlays in V6.
;003		ACK	Add routines FUNGOT and FUNROT for V10.
;004	400		Changed GCH routineeee to get channel 0 last.
;005		SCC	Added (reserved) 2 entry points for DBMS usage.
;006	472	JM	Use PAGE. UUOs if they exist in FUNCBC.
;007	512	MDL	Prevent MCS page pool from disappearing.
;010	514	DZN	Check OTS list too in FUNCBC.
;011		DMN	Add function to get memory on page boundary
;012		DSB	Change routines to make page bound 'CORE GET'
;			work and to fix other bugs.
;013		DMN	Add function to return memory on page boundary
;			to be compatible with FOROTS for DBMS.
;014	652	DMN	Make CBC routine work with SORT 4C when all buffers have been returned.
;015	1002	DMN/JM	Make CBC work when CORPT. goes 0 but overlays still exist.
;016	1025	JEH	If CORPT. zero, don't try to free core.

SUBTTL	DEFINE SYMBOLS


;ACCUMULATORS
T0=0		;HOLDS STATUS
T1=1
T2=2
T3=3
T4=4
T5=5
P1=6		;POINTER TO ARGS
L=16		;POINTER TO ARG LIST
P=17		;PUSHDOWN POINTER


	DEFINE FUNDIR,<
	FNCTN	ILL		;0; ILLEGAL FUNCTION
	FNCTN	GAD		;1; GET CORE AT ADDRESS
	FNCTN	COR		;2; GET CORE FROM ANY ADDRESS
	FNCTN	RAD		;3; RETURN CORE AT ADDRESS
	FNCTN	GCH		;4; GET A CHANNEL
	FNCTN	RCH		;5; RETURN A CHANNEL
	FNCTN	GOT		;6; GET CORE FROM OTS LIST
	FNCTN	ROT		;7; RETURN CORE TO OTS LIST
	FNCTN	RNT		;10; GET RUNTIME FROM OTS
	FNCTN	IFS		;11; GET DEV:FILE[PPN] FROM OTS
	FNCTN	CBC		;12; CUT BACK CORE
	FNCTN	RRS		;13; READ RETAIN STATUS (MAY EVENTUALLY INVOLVE MORE)
	FNCTN	WRS		;14; WRITE RETAIN STATUS (DITTO)
	FNCTN	PAG		;15; GET CORE ON PAGE BOUNDARY
	FNCTN	RPG		;16; RETURN MEMORY ON A PAGE BOUNDARY
	>

	FUN.ZZ==0
	DEFINE FNCTN(A),<
	JRST	FUN'A		;DEFINE DISPATCH TO PROCESSING ROUTINE
	FUN.ZZ==FUN.ZZ+1	;COUNT NUMBER OF ENTRIES IN TABLE
	>

FUNDSP:	FUNDIR			;DEFINE DISPATCH TABLE

SUBTTL	FUNCTION DISPATCH

	ENTRY	FUNCT.

;CALLS TO FUNCT. CONFORM TO THE DEC STANDARD CALLING SEQUENCE
;
;THE ARG LIST HAS THE GENERAL FORM
;
;		-ARG COUNT,,0
; ARGBLK:	TYPE,,[FUNCTION]
;		TYPE,,[ERROR CODE]
;		TYPE,,[STATUS]
;		TYPE,,[ARG1]
;		TYPE,,[ARG2]
;		TYPE,,[ARG3]
;

		DEFINE FUNBLK,<
		FUNARG	FUN,IND
		FUNARG	ERR,IND
		FUNARG	STS,IND
		FUNARG	RG1,IND
		FUNARG	RG2,IND
		FUNARG	RG3,IND
		>


		FUN.YY==0
		DEFINE FUNARG(A,B)<
		FN.'A==FUN.YY		;SET INDEX INTO ARGBLK
		FUN.YY==FUN.YY+1	;COUNT ENTRIES IN ARGBLK
		>

		FUNBLK			;DEFINE ARGBLK SYMBOLS

	SIXBIT	/FUNCT./	;FOR TRACE
FUNCT.:	PUSHJ	P,.SAVE		;SAVE REGISTERS
	SETZ	P1,0		;LOCATE THE FUNCTION CODE
	PUSHJ	P,FUNADR	;LOCATE THE FUNCTION CODE
	SKIPL	P1,0(P1)	;LOAD THE ARGUMENT
	CAIL	P1,FUN.ZZ	;IS THE FUNCTION DEFINED?
	SETZ	P1,0		;DEFAULT TO ILLEGAL FUNCTION
	PUSHJ	P,@FUNDSP(P1)	;DISPATCH TO FUNCTION ROUTINE
	MOVEI	P1,FN.STS	;LOCATE STATUS ARGUMENT
	PUSHJ	P,FUNADR	;LOCATE STATUS ARGUMENT
	MOVEM	T0,0(P1)	;STORE STATUS ARGUMENT
	POPJ	P,		;RETURN

SUBTTL	FUNCTION ILL - ILLEGAL FUNCTION

;FUNCTION ILL - ILLEGAL FUNCTION
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARGBLK IS IGNORED
;ALWAYS RETURNS STATUS -1

FUNILL:	SETO	T0,		;SET ILLEGAL FUNCTION
	POPJ	P,		;RETURN TO USER

SUBTTL	FUNCTION GAD - GET CORE AT SPECIFIED ADDRESS

;FUNCTION GAD - GET CORE AT ADDRESS
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS TO ALLOCATE CORE AT
;ARG2:	SIZE OF BLOCK TO ALLOCATE
;
;STATUS 0:	CORE ALLOCATED
;STATUS 1:	NOT ENOUGH CORE IN SYSTEM
;STATUS 2:	CANNOT ALLOCATE AT SPECIFIED LOCATION
;STATUS 3:	ILLEGAL ARGUMENTS

FUNGAD:	PUSHJ	P,G2ARGS	;GO GET THE ARGS.
	JUMPN	T0,CPOPJ	;BAD ARGS, LEAVE.

;	(T4) = ADDRESS OF FIRST LOCATION WANTED.
;	(T5) = ADDRESS OF LAST LOCATION WANTED.

	SKIPN	T1,HLOVL.##	;IS THIS THE FIRST TIME?
	PUSHJ	P,SETHLO	;YES, GO SET UP HLOVL.
	HLRZ	T2,T1		;(T2) = HIGHEST POSSIBLE FREE CORE LOC.
	HRRZI	T1,(T1)		;(T1) = LOWEST POSSIBLE FREE CORE LOC.
	CAILE	T1,(T4)		;DOES HE WANT CORE BELOW THE LOWEST?
	JRST	FUNST2		;YES, WELL HE CAN'T HAVE IT - ERROR.
	CAIGE	T2,(T5)		;DOES HE WANT CORE ABOVE THE HIGHEST?
	PUSHJ	P,XPAND		;YES, GO TRY TO GET SOME MORE.
	MOVEI	T1,CORPT.##	;GET THE ADDRESS OF THE POINTER TO THE
				; FIRST BLOCK.
	PUSHJ	P,GADLST	;GO TRY TO GET THE SPACE.
	  JRST	FUNST2		;CAN'T - RETURN A STATUS OF 2.
FUNGAH:	SETZB	T0,(T4)		;CLEAR FIRST WORD AND RETURN A STATUS OF 0.
	POPJ	P,		;RETURN

SUBTTL	ROUTINE TO GET CORE (FROM A FREE CORE LIST) AT A SPECIFIED ADDRESS.

COMMENT \*************************

CALL:
	PUSHJ	P,GADLST

ENTRY CONDITIONS:

	(T1) = ADDRESS OF POINTER TO A FREE CORE LIST.
	(T4) = STARTING ADDRESS OF BLOCK WANTED
	(T5) = ADDRESS OF LAST WORD IN BLOCK WANTED

EXIT CONDITIONS:

	(T1), (T2), (T3)	DESTROYED
	(T4), (T5)		UNCHANGED

	IF THE CORE HAS BEEN ALLOCATED IT HAS BEEN REMOVED FROM THE
FREE CORE LIST AND THE RETURN IS TO CALL+2.
	IF THE CORE CAN NOT BE ALLOCATED THE FREE CORE LIST IS UNCHANGED
AND THE RETURN IS TO CALL+1.

************************\

GADLST:
GADLS1:	HRRZ	T2,(T1)		;GET ADR OF NEXT BLOCK OF FREE CORE.
	JUMPE	T2,CPOPJ	;IF THERE IS NO MORE RETURN.
	CAIGE	T4,(T2)		;COULD THE BLOCK WE WANT STILL BE ON
				; THE LIST?
	POPJ	P,		;NO WAY, ERROR RETURN.
	HLRZ	T3,(T2)		;GET THE ADR OF THE LAST LOC IN THIS BLOCK.
	CAILE	T5,(T3)		;IS THE LAST LOC WE WANT IN THIS BLOCK?
	SKIPA	T1,T2		;NO, CURRENT BLOCK BECOMES PTR TO NEXT.
	AOSA	(P)		;BUMP RETURN ADDRESS.
	JRST	GADLS1		;GO LOOK AT THE NEXT BLOCK.

;WE COME HERE WHEN WE KNOW THAT THE CORE WE WANT IS IN THE CURRENT BLOCK.
;STATE OF THINGS:
;	(T1) = ADR OF PTR TO CURRENT BLOCK.
;	(T2) = ADR OF CURRENT BLOCK.
;	(T3) = LAST LOCATION OF CURRENT BLOCK.
;	(T4), (T5) HAVE NOT BEEN CHANGED.

	HRL	T1,(T2)		;GET THE PTR TO THE NEXT BLOCK.
	CAIE	T2,(T4)		;START ALLOCATION AT THE FIRST WORD?
	SOJA	T4,GADLS3	;NO, FORM THE ADR OF THE NEW LAST LOC
				; AND GO BREAK UP THE BLOCK.
	HLRM	T1,(T1)		;DELINK THE BLOCK.
GADLS4:	CAIE	T3,(T5)		;END THE ALLOCATION AT THE LAST WORD.
	AOJA	T5,GADLS2	;NO, GO FORM A NEW BLOCK AND LINK IT IN.
	POPJ	P,		;RETURN.

;HERE WE ADD A NEW BLOCK, WHICH IS THE LAST PART OF THE CURRENT BLOCK.

GADLS2:	HRRM	T5,(T1)		;SET THE POINTER TO THE NEW BLOCK.
	HLRM	T1,(T5)		;SET THE PTR TO NEXT IN THE NEW BLOCK.
	HRLM	T3,(T5)		;SET THE LAST LOC IN THE NEW BLOCK.
	SOJA	T5,CPOPJ	;RESTORE T5 AND RETURN.

;HERE WE ALLOCATE PART OF THE CURRENT BLOCK NOT BEGINNING AT THE 
; FIRST LOCATION.

GADLS3:	HRLM	T4,(T2)		;SET THE NEW LAST LOCATION IN THE 
				; CURRENT BLOCK.
	HRRI	T1,(T2)		;SET THE CURRENT BLOCK AS THE POINTER
				; TO THE CURRENT BLOCK.   (HUH?)
	AOJA	T4,GADLS4	;RESTORE THE ADR OF THE FIRST WORD
				; ALLOCATED AND GO SEE IF WE WANT ALL OF
				; THE REMAINDER OF THE BLOCK.

SUBTTL	FUNCTION COR - GET CORE AT ANY ADDRESS

;FUNCTION COR - GET CORE FROM ANY ADDRESS
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS OF BLOCK ALLOCATED
;ARG2:	SIZE OF BLOCK TO ALLOCATE
;
;STATUS 0:	CORE ALLOCATED
;STATUS 1:	NOT ENOUGH CORE IN SYSTEM
;STATUS 3:	ILLEGAL ARGUMENT

FUNCOR:	PUSHJ	P,FUNRG2	;LOCATE SECOND ARGUMENT
	SKIPLE	T5,0(P1)	;LOAD SIZE OF BLOCK
	TLNE	T5,-1		;POSITIVE 18 BIT ADDRESS
	JRST	FUNST3		;ILLEGAL ARGUMENT

;	(T5) = NUMBER OF WORDS TO ALLOCATE.

	SKIPN	HLOVL.##	;IS THE OVERLAY FREE CORE LIST SET UP?
	JRST	FUNST1		;NO, WE CAN'T GET IT THEN.
	MOVEI	T1,CORPT.##	;POINT AT THE OVERLAY FREE CORE LIST.
	PUSHJ	P,CORLST	;TRY TO GET THE CORE.
	  SKIPA	T1,.JBREL##	;CAN'T, GO TRY EXPANDING.
	JRST	FUNCRD		;GOT IT, RETURN.
	MOVEI	T4,(T5)		;SAVE THE NUMBER OF WORDS TO GET.
	ADDI	T5,(T1)		;WHAT THE NEW .JBREL SHOULD BE.
	PUSHJ	P,XPAND		;GO GET MORE CORE.
	MOVEI	T5,(T4)		;RESTORE THE NUMBER OF WORDS TO GET.
	MOVEI	T1,CORPT.##	;POINT AT THE OVERLAY'S FREE CORE LIST.
	PUSHJ	P,CORLST	;TRY TO GET IT NOW.
	  JRST	FUNST1		;IF WE CAN'T GET IT NOW WE NEVER CAN.

FUNCRD:	PUSHJ	P,FUNRG1	;LOCATE THE FIRST ARG.
	MOVEM	T4,(P1)		;TELL CALLER WHERE HIS CORE IS.
	JRST	FUNGAH		;GO CLEAR THE FIRST WORD, AND RETURN
				; A STATUS OF ZERO.

SUBTTL	GET CORE (FROM A FREE CORE LIST) AT ANY ADDRESS.

COMMENT \***********************
CALL:
	PUSHJ	P,CORLST

ENTRY CONDITIONS:

	(T1) = ADDRESS OF POINTER TO A FREE CORE LIST.
	(T5) = NUMBER OF WORDS WANTED

EXIT CONDITIONS:

	(T1), (T2), (T3)	DESTROYED
	(T4)			ADDRESS OF WHERE WE GOT THE CORE.
	(T5)			UNCHANGED

	IF THE CORE WAS ALLOCATED, THE RETURN IS TO CALL+2 AND THE
FREE CORE LIST HAS BEEN UPDATED.
	IF THE CORE CAN NOT BE ALLOCATED THE RETURN IS TO CALL+1 AND
THE FREE CORE LIST IS UNCHANGED.
************************\

CORLST:
CORLS1:	HRRZ	T2,(T1)		;GET ADR OF THIS BLOCK OF FREE CORE.
	JUMPE	T2,CPOPJ	;IF THER ARE NO MORE, LEAVE.
	HLRZ	T3,(T2)		;GET LAST LOC OF THIS BLOCK OF FREE CORE.
	SUBI	T3,-1(T2)	;FORM THE LENGTH OF THE BLOCK.
	CAIGE	T3,(T5)		;IS THIS BLOCK BIG ENOUGH?
	SKIPA	T1,T2		;NO, GET PTR TO NEXT.
	AOSA	(P)		;YES, SET RETURN ADR.
	JRST	CORLS1		;GO LOOK AT THE NEXT BLOCK.

;WE FOUND A BLOCK BIG ENOUGH.
;STATE OF THINGS:
;	(T1) = ADR OF PTR TO THIS BLOCK
;	(T2) = ADR OF THIS BLOCK
;	(T3) = SIZE OF THIS BLOCK
;	(T4), (T5) HAVE NOT BEEN CHANGED.

	HRRZI	T4,(T2)		;SET RETURN PARAMETER.
	HRL	T1,(T2)		;GET ADR OF NEXT BLOCK.
	HLRM	T1,(T1)		;DELINK THE BLOCK.
	CAIN	T3,(T5)		;DOES HE WANT THE WHOLE BLOCK?
	POPJ	P,		;YES, RETURN.
;WE HAVE TO PUT PART OF THE BLOCK BACK ON THE LIST.

	ADDI	T3,-1(T2)	;FORM ADR OF THE LAST LOC OF THE NEW BLOCK.
	ADDI	T2,(T5)		;FORM ADR OF THE FIRST LOC OF THE NEW BLOCK.
	HRRM	T2,(T1)		;LINK THE NEW BLOCK IN THE LIST.
	HRLM	T3,(T2)		;PUT THE LAST LOC OF THE NEW BLOCK IN IT.
	HLRM	T1,(T2)		;SET THE LINK TO NEXT.
	POPJ	P,		;RETURN.

SUBTTL	ROUTINE TO INITIALIZE HLOVL.

SETHLO:	CAMGE	T4,.JBFF##	;DO WE WANT CORE BELOW .JBFF?
	JRST	SETHL1		;YES, CAN'T HAVE IT.
	HRRI	T1,(T4)		;HIGHEST LOCATION IN OVERLAY AREA.
	HRLI	T1,-1(T4)	;LOWEST LOCATION IN OVERLAY AREA.
	MOVEM	T1,HLOVL.##	;SET UP HLOVL.
	POPJ	P,		;RETURN.

SETHL1:	POP	P,0		;POP OFF THE RETURN.
	JRST	FUNST3		;GIVE AN ILLEGAL ARGUMENT STATUS.

SUBTTL	FUNCTION RAD - RETURN CORE AT ADDRESS

;FUNCTION RAD - RETURN CORE AT ADDRESS
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS OF BLOCK TO BE RETURNED
;ARG2:	SIZE OF BLOCK TO BE RETURNED
;
;STATUS 0:	CORE DEALLOCATED
;STATUS 1:	CORE NOT DEALLOCATABLE
;STATUS 3:	ILLEGAL ARGUMENT

FUNRAD:	MOVE	T1,HLOVL.##	;HIGH,,LOW LIMITS.
	PUSHJ	P,R2ARGS	;GO GET THE ARGS AND CHECK THEM.
	JUMPE	T0,FUNRAH	;OK, GO TRY TO RETURN THE CORE.

	TLNN	T4,-1		;IF THE VALUES AREN'T
	TLNE	T5,-1		; REASONABLE,
	JRST	FUNST1		;ERROR

;THE CORE ISN'T IN THE OVERLAY AREA, SEE IF IN THE OTS AREA.

	MOVE	T1,HLOTC.##	;HIGH,,LOW LIMITS.
	HLRZ	T2,T1

	CAIL	T4,(T1)		;IF THE START ADDRESS IS BELOW THE
	CAILE	T5,(T2)		; LOWEST ADDRESS OR THE END ADDRESS IS
	JRST	FUNST1		; ABOVE THE HIGHEST ADDRESS, THE ARGS
				; ARE BAD, RETURN.
	SETZ	T0,		;CLEAR THE STATUS.
	JRST	FUNRTB		;GO TRY TO RETURN THE CORE TO THE OTS LIST.

FUNRAH:	MOVEI	T1,CORPT.##	;GET THE ADDR OF THE PTR TO THE
				; FIRST BLOCK.
	PUSHJ	P,RADLST	;GO RETURN THE CORE.
	  JRST	FUNST1		;CAN'T EVEN GIVE IT AWAY - ERROR.
	JRST	FUNST0		;ALL IS WELL

SUBTTL	RETURN CORE TO A FREE CORE LIST.

COMMENT \***********************

CALL:
	PUSHJ	P,RADLST

ENTRY CONDITIONS:

	(T1) = ADDRESS OF POINTER TO A FREE CORE LIST.
	(T4) = ADDRESS OF FIRST LOCATION TO BE RETURNED
	(T5) = ADDRESS OF LAST LOCATION TO BE RETURNED

EXIT CONDITIONS:

	(T1), (T2), (T3)	DESTROYED
	(T4), (T5)		UNCHANGED

	IF THE CORE WAS DEALLOCATED THE RETURN IS TO CALL+2 AND THE
FREE CORE LIST IS UPDATED.
	IF THE CORE WAS NOT DEALLOCATED BECAUSE IT (OR PART OF IT
WAS ALREADY ON THE FREE CORE LIST) THE RETURN IS TO CALL+1 AND THE
FREE CORE LIST IS UNCHANGED.

***********************\

RADLST:	CAILE	T4,(T5)		;IF THE LAST LOCATION IS LOWER
	POPJ	P,		; THE FIRST LOCATION, RETURN.

RADLS1:	HRRZ	T2,(T1)		;GET THE ADR OF THIS BLOCK.
	JUMPE	T2,RADLS5	;IF ZERO ADD IT AT THE END OF THE LIST.
	CAIL	T2,(T4)		;DOES IT GO AFTER THE CURRENT BLOCK?
	JRST	RADLS2		;NO, GO SEE IF IT GOES AFTER THE
				; PRECEEDING BLOCK.
	HRRZI	T1,(T2)		;MAKE THIS THE PTR TO NEXT.
	JRST	RADLS1		;AND LOOP.

;THE BLOCK TO BE ADDED GOES BEFORE THE CURRENT BLOCK.

RADLS2:	HLRZ	T3,(T1)		;GET THE LAST ADR OF THE PREVIOUS BLOCK.
	CAILE	T4,(T3)		;IF THE FIRST ADDRESS OF THEBLOCK
	CAIL	T5,(T2)		; TO BE ADDED IS LESS THAN THE LAST
				; ADR OF THE PREVIOUS BLOCK OR
				; THE LAST ADDRESS IS GREATER THAN
				; THE FIRST ADDRESS OF THE NEXT BLOCK
	POPJ	P,		; IT IS AN ERROR.

;  ..

;  ..

;ALL IS WELL. LINK THIS BLOCK IN.

	HRRM	T4,(T1)		;PREVIOUS POINTS TO THIS.
	HRLM	T5,(T4)		;SET LAST ADR IN THIS BLOCK.
	HRRM	T2,(T4)		;SET PTR TO NEXT.

;SEE IF WE CAN COMBINE BLOCKS.
;STATE OF THINGS:
;	(T1) = ADR OF PREVIOUS
;	(T2) = ADR OF NEXT
;	(T4) = ADR OF CURRENT

	CAIE	T2,1(T5)	;CAN WE MERGE THIS WITH THE NEXT?
	JRST	RADLS3		;NO, GO SEE ABOUT THE PREVIOUS.
	MOVE	T3,(T2)		;LAST LOC,,PTR TO NEXT
	MOVEM	T3,(T4)		;THEY ARE MERGED.
	SETZM	(T2)		;KEEP THE CORE CLEAN.

RADLS3:	CAIE	T4,(T5)		;CLEAN UP THE CORE.
	SETZM	1(T4)
	CAIG	T5,1(T4)
	JRST	RADLS4
	HRLI	T3,1(T4)
	HRRI	T3,2(T4)
	BLT	T3,(T5)
RADLS4:	HLRZ	T3,(T1)		;GET ADR OF PREVIOUS BLOCK.
	AOS	(P)		;UPDATE THE RETURN ADR.
	CAIE	T4,1(T3)	;CAN WE MERGE WITH THE PREVIOUS BLOCK?
	POPJ	P,		;NO, RETURN.
	MOVE	T3,(T4)		;LAST LOC,,PTR TO NEXT
	MOVEM	T3,(T1)		;THEY ARE MERGED.
	SETZM	(T4)		;KEEP OUR CORE CLEAN.
	POPJ	P,		;RETURN.

;COME HERE TO ADD THE BLOCK AT THE END OF THE LIST.

RADLS5:	HRLZM	T5,(T4)		;LAST ADR OF BLOC,,0
	HRRM	T4,(T1)		;SET PTR TO THIS BLOCK.
	JRST	RADLS3		;GO SEE IF WE CAN MERGE WITH PREVIOUS.

SUBTTL	FUNCTION GCH - GET AN I/O CHANNEL

;FUNCTION GCH - GET AN I/O CHANNEL
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	CHANNEL # ALLOCATED
;ARG2:	IGNORED
;
;STATUS 0:	CHANNEL ALLOCATED
;STATUS 1:	NO CHANNELS AVAILABLE

FUNGCH:	PUSHJ	P,FUNRG1	;LOCATE ARG1
       	SKIPN	T1,OPNCH.##	;[400] ANY CHANNELS LEFT?
	JRST	FUNST1		;NO CHANNELS AVAILABLE
	TLZ 	T1,400000	;[400] SAVE CHANNEL 0 FOR LAST
	JFFO	T1,.+1		;[400] GET CHANNEL NUMBER
	MOVSI	T1,400000	;[400] SET BIT TO SHIFT
	MOVN	T3,T2		;[400] SET TO SHIFT RIGHT
	LSH	T1,(T3)		;[400] POSITION BIT
	ANDCAM	T1,OPNCH.##	;[400] SET CHANNEL AS UNAVAILABLE
	HRRZM	T2,0(P1)	;[400] STORE CHANNEL #
	JRST	FUNST0		;[400] SET RETURN STATUS, SUCCESSFUL AND RETURN

SUBTTL	FUNCTION RCH - RETURN AN I/O CHANNEL
;FUNCTION RCH - RETURN AN I/O CHANNEL
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	CHANNEL # TO BE RETURNED
;ARG2:	IGNORED
;
;STATUS 0:	CHANNEL RETURNED
;STATUS 1:	INVALID OR NON-USER CHANNEL

FUNRCH:	PUSHJ	P,FUNRG1	;LOCATE ARG1
	SKIPL 	T1,(P1)		;[400] LOAD CHANNEL #
	CAILE	T1,17		;MUST BE BETWEEN 0 AND 20
	JRST	FUNST1		;CANNOT RETURN
	MOVN	T1,T1		;SHIFT TO THE RIGHT
	MOVSI	T0,(1B0)	;MASK BIT
	LSH	T0,(T1)		;POSITION THE MASK
	ORM	T0,OPNCH.##	;MAKES THE CHANNEL AVAILABLE
	TDZA	T0,T0		;SET STATUS TO 0
FUNST1:	MOVEI	T0,1		;SET STATUS TO 1
	POPJ	P,

SUBTTL	FUNCTION GOT - GET CORE FROM OTS LIST

;FUNCTION GOT - GET CORE FROM OTS LIST
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS OF BLOCK ALLOCATED
;ARG2:	SIZE OF BLOCK TO ALLOCATE
;
;STATUS 0:	CORE ALLOCATED
;STATUS 1:	NOT ENOUGH CORE IN SYSTEM
;STATUS 2:	CAN NOT ALLOCATE AT SPECIFIED ADDRESS
;STATUS 3:	ILLEGAL ARGUMENT

FUNGOT:	PUSHJ	P,FUNRG2	;PICK UP THE SECOND ARG.
	SKIPLE	T5,(P1)		;IF IT IS LESS THAN 1 OR IT IS
	TLNE	T5,-1		; TOO BIG,
	JRST	FUNST3		; COMPLAIN.

	HRRZI	T1,OTCPT.##	;POINT AT THE OTS FREE CORE LIST.
	PUSHJ	P,CORLST	;GO TRY TO GET THE CORE.
	  CAIA			;CAN'T, TRY EXPANDING.
	JRST	FUNCRD		;GOT IT, GO RETURN ITS ADDR AND RETURN.
	PUSHJ	P,MORMEM	;FIT REQUEST INTO AVAILABLE MEMORY
	  JRST	FUNST1		;  NO MORE ROOM
	  JRST	FUNST2		;  NO ROOM UNDER OVERLAY AREA
	JRST	FUNGOT		; GOT IT--RESTART THE PROCESS

;FUNCTION PAG - GET CORE FROM OTS LIST ON A PAGE BOUNDARY
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS OF BLOCK ALLOCATED
;ARG2:	SIZE OF BLOCK TO ALLOCATE
;
;STATUS 0:	CORE ALLOCATED
;STATUS 1:	NOT ENOUGH CORE IN SYSTEM
;STATUS 3:	ILLEGAL ARGUMENT

FUNPAG:	PUSHJ	P,FUNRG2	;LOCATE SECOND ARGUMENT
	SKIPG	T5,0(P1)	;LOAD SIZE OF BLOCK.
	JRST	FUNST3		;0 LENGTH.
	ADDI	T5,777		;[DSB-4]GET MORE AND THEN PAGE ALIGN
	TLNE	T5,-1		;[DSB-4] TOO BIG.
	JRST	FUNST3		;ILLEGAL ARGUMENT

;	(T5) = NUMBER OF WORDS TO ALLOCATE.

	HRRZI	T1,OTCPT.	;POINT AT THE OTS FREE CORE LIST.
	PUSHJ	P,CORLST	;GO TRY TO GET THE CORE.
	  SKIPA			;[DSB-4]CAN'T, TRY EXPANDING.
	JRST	FUNP50		;GOT THE MEMORY--MAKE IT PAGE ALIGNED.
	PUSHJ	P,MORMEM	;[DSB-4]NOT ENOUGH MEMORY--GET SOME MORE
	  JRST	FUNST1		;  NOT ENOUGH
	  JRST	FUNST2		;  NOT ENOUGH ON OTS LIST BEFORE OVERLAY
	JRST	FUNPAG		;GOT IT--RESTART.

FUNP50:		;HAVE THE MEMORY--TRIM TO PAGE BOUNDRY
	SUBI	T5,777		;SIZE AFTER TRIMMING
	PUSH	P,T5		;   THIS IS THE PROPER ALLOCATION AMOUNT..
	PUSH	P,T4		;SAVE ADDRESS OF ALLOCATED MEMORY.
	PUSH	P,[0]		;SAVE AMOUNT OF ANTERIOR TRIM.
	TRZN	T4,777		;IF ON A PAGE BOUNDRY
	JRST	FUNP60		;  THEN NO NEED TO TRIM LOWER BOUND
	MOVEI	T3,1000(T4)	;GET PAGE BOUNDRY WITHIN ALLOCATED RANGE
	POP	P,T2		;RESTORE GUESSED AMOUNT OF FRONTAL TRIM
	POP	P,T4		;  AND THE ALLOCATED MEMORY ADDRESS.
	PUSH	P,T3		;SAVE INSTEAD THE PAGE ALIGNED ADDRESS.
	MOVEI	T5,-1(T3)	;LAST ADDRESS TO TRIM.
	SUBI	T3,(T4)		;DETERMINE HOW MUCH TO TRIM OFF FRONTAL.
	PUSH	P,T3		;AND SAVE TRIM AMOUNT.
	PUSHJ	P,RADLST	;RESTORE THIS AREA (T4)-(T5) TO FREE LIST.
	  JRST	[POP P,0	;IF WE CAN'T--TROUBLE
		 POP P,0
		 POP P,0
		 JRST FUNST1]
	;  ..

	;  ..
FUNP60:
	POP	P,T3		;RESTORE AMOUNT TRIMED OFF.
	MOVEI	T2,777		;GREATEST AMOUNT OF TRIM
	SUBI	T2,(T3)		;AMOUNT LEFT TO TRIM OFF POSTERIOR.
	JUMPE	T2,FUNP70	;NONE TO TRIM.
	MOVE	T4,(P)		;ADDRESS OF REGION ALLOCATED.
	MOVE	T5,-1(P)	;ACTUAL AMOUNT ALLOCATED.
	ADDI	T4,(T5)		;ADDRESS TO START TRIM.
	MOVEI	T5,(T4)
	ADDI	T5,-1(T2)	;LAST ADDRESS TO TRIM.
	PUSHJ	P,RADLST	;FREE THIS MEMORY
	  JRST	[POP P,0	;IF FAILS--THEN TROUBLE
		 POP P,0
		 JRST FUNST1]
FUNP70:
	POP	P,T4		;ADDRESS OF PAGE ALIGNED MEMORY
	POP	P,T5		;SIZE OF MEMORY
	JRST	FUNCRD		;WE ARE DONE

SUBTTL	FUNCTIONS ROT & RPG  - RETURN CORE TO OTS LIST

;FUNCTION ROT - RETURN CORE TO OTS LIST
;FUNCTION RPG - RETURN CORE TO OTS LIST ON PAGE BOUNDARY
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	ADDRESS OF BLOCK TO BE RETURNED
;ARG2:	SIZE OF BLOCK TO BE RETURNED
;
;STATUS 0:	CORE DEALLOCATED
;STATUS 1:	CORE NOT DEALLOCATABLE
;STATUS 3:	ILLEGAL ARGUMENT

FUNRPG:
FUNROT:	MOVE	T1,HLOTC.##	;HIGH,,LOW LIMITS.
	PUSHJ	P,R2ARGS	;GO GET THE ARGS AND CHECK THEM.
	JUMPN	T0,FUNRAD	;IT ISN'T IN THE OTS LIST, GO SEE IF
				; IT'S IN THE OVERLAY LIST.

;	(T4) = ADDRESS OF FIRST LOCATION TO RETURN.
;	(T5) = ADDRESS OF LAST LOCATION TO RETURN.

FUNRTB:	MOVEI	T1,OTCPT.##	;POINT AT THE LIST.
	PUSHJ	P,RADLST	;RETURN THE CORE.
	  JRST	FUNST1		;CAN'T, COMPLAIN.

;DETERMINE IF WE CAN RESET .JBFF (MAY BE IMPORTANT FOR OVERLAYS)

	MOVEI	T1,OTCPT.##	;ADDRESS OF FREE CORE LIST
	HRRZ	T2,(T1)		;ADDRESS OF FIRST FREE BLOCK.
	JUMPE	T2,FUNRTL	;JUMP IF NO FREE MEMORY.

FUNRTD:	HRRZ	T3,(T2)		;GET ADDR OF FOLLOWING BLOCK.
	JUMPE	T3,FUNRTH	;THIS IS THE ONE TO RETURN.
	MOVEI	T1,(T2)		;(T1)=PTR TO BLOCK N.
	MOVEI	T2,(T3)		;(T2)=PTR TO BLOCK N+1.
	JRST	FUNRTD		;GO LOOK FOR BLOCK N+2.

FUNRTH:		;T1 POINTS TO PREVIOUS BLOCK.
		;T2 POINTS TO CURRENT BLOCK.
	HLRZ	T5,(T2)		;GET LAST ADDRESS IN CURRENT BLOCK.
	HRRZ	T3,.JBFF	;  AND ADDRESS OF FIRST FREE LOCATION.
	CAIE	T3,1(T5)	;IF THESE ARE NOT CONSECUTIVE
	 POPJ	P,		;  THEN WE CANNOT CUT BACK .JBFF.
	MOVEI	T4,-1(T2)	;GET HIGHEST MEMORY ADDRESS ALLOCATED.
	HRRM	T2,.JBFF##	;THE NEW .JBFF
	HRLM	T4,HLOTC.##	;THE NEW UPPER LIMIT.
	HLLZS	(T1)		;ZERO THE LINK.

FUNRTL:	MOVE	T1,HLOTC.##	;GET THE HIGH AND LOW LIMITS.
	HLRZ	T2,T1
	CAIL	T2,(T1)		;IF THE HIGH LIMIT IS ABOVE
	POPJ	P,		; THE LOW LIMIT, RETURN.
	SETZM	HLOTC.##	;CLEAR THE LIMITS AND THE
	SETZM	OTCPT.##	; POINTER.
	POPJ	P,		;RETURN

SUBTTL	FUNCTION RNT - RETURN INITIAL RUNTIME FROM OTS

;FUNCTION RNT - RETURN INITIAL RUNTIME FROM OTS
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	RUNTIME FROM OTS
;ARG2:	IGNORED
;
;STATUS 0:	RUNTIME RETURNED
;STATUS 1:	RUNTIME NOT AVAILABLE

FUNRNT:	PUSHJ	P,FUNRG1	;LOCATE FIRST ARG
	MOVE	T1,RUN.TM##	;GET RUNTIME FROM OTS
	MOVEM	T1,(P1)		;STORE
	JRST	FUNST0		;RETURN OK

SUBTTL	FUNCTION IFS - RETURN INITIAL DEV:FILE[PPN] FROM OTS

;FUNCTION IFS - RETURN INITIAL DEV:FILE[PPN] FROM OTS
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	DEV:
;ARG2:	FILE NAME
;ARG3:	[PPN] OR <0,,PATH POINTER>
;
;STATUS 0:	INITIAL FILE SPEC RETURNED
;STATUS 1:	INITIAL FILE SPEC NOT AVAILABLE

FUNIFS:	PUSHJ	P,FUNRG1	;LOCATE FIRST ARG
	SKIPN	T1,RN.DEV##	;GET DEVICE
	MOVSI	T1,'DSK'	;ASSUME DSK
	MOVEM	T1,(P1)		;STORE
	PUSHJ	P,FUNRG2	;LOCATE SECOND ARG
	MOVE	T1,RN.NAM##	;GET NAME
	JUMPN	T1,.+4		;OK
	HRROI	T1,3		;TRY GETTAB
	GETTAB	T1,		;IF NOT IN ACCS
	  JRST	FUNST1		;GIVE ERROR RETURN
	MOVEM	T1,(P1)		;STORE
	MOVEI	P1,FN.RG3	;LOCATE THIRD ARG
	PUSHJ	P,FUNADR
	MOVE	T1,RN.PPN##	;GET PPN
	MOVEM	T1,(P1)		;STORE
	JRST	FUNST0		;RETURN OK

SUBTTL	FUNCTION CBC - CUT BACK CORE

;FUNCTION CBC - CUT BACK CORE
;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1:	IGNORED
;ARG2:	IGNORED
;
;STATUS 0:	ALWAYS

FUNCBC:	SKIPN	HLOVL.##	;[1002] ARE OVERLAYS IN USE?
	JRST	TRYOTS		;[514] NO--TRY IN THE OTS LIST THEN
	SKIPN	CORPT.		;[1025] IS THERE ANY FREE CORE?
	JRST	FUNST0		;[1025] NO
	MOVEI	T1,CORPT.##	;[514] YES--GET OVERLAY LIST HEAD ADDR,
	MOVEI	T4,HLOVL.##	;[514]   LIMITS OF OVERLAY AREA
	JRST	FUNCB1		;[514]   AND GO FIND LAST BLOCK IN LIST

TRYOTS:	MOVE	T1,.JBFF	;[652] LOAD HIGHEST ADDRESS IN USE INCASE NO LIST
	MOVEI	T4,HLOTC.##	;[514] GET LIMITS OF OTS AREA POINTER
	SKIPN	OTCPT.##	;[514] ANY CORE IN THE OTS LIST?
	JRST	FUNCB5		;[652] [514] NO, DELETE ANY PAGES ABOVE .JBFF
	MOVEI	T1,OTCPT.##	;[514] YES--GET OTS LIST HEAD ADDR,
;	JRST	FUNCB1		;[514]   AND GO FIND LAST BLOCK IN LIST

FUNCB1:	HRRZ	T2,(T1)		;[514] GET ADDR OF FIRST BLOCK IN LIST
	HRRZ	T3,(T2)		;[514] GET ADDR OF FOLLOWING BLOCK (IF ANY)
	JUMPE	T3,FUNCB2	;[514] NO MORE--T2 HAS ADDR OF LAST BLOCK
	MOVEI	T1,(T2)		;[514] (T1) = POINTER TO BLOCK N
	MOVEI	T2,(T3)		;[514] (T2) = POINTER TO BLOCK N+1
	JRST	.-4		;[514] LOOP 'TIL WE FIND LAST BLOCK

;HERE WHEN WE FIND THE LAST BLOCK. ACS:
;	(T1) = ADDR OF POINTER TO LAST BLOCK. POINTER GETS ZEROED LATER.
;	(T2) = ADDR OF LAST BLOCK. UNLINK IT AND TRY TO GIVE ITS CORE BACK TO MONITOR.
;	(T4) = ADDR OF HL???. WORD.

FUNCB2:	HLRZ	T3,(T2)		;[514] GET ADDR OF LAST WORD IN BLOCK
	HLRZ	T5,(T4)		;[514] GET HIGHEST ADDR WE'RE MANAGING
	CAIE	T3,(T5)		;[514] IF NOT THE SAME THEN
	JRST	FUNST0		;[514]   SOMEONE'S ABOVE US, SO CAN'T SHRINK
	MOVEI	T3,-1(T2)	;[514] SAME--GET ADDR OF LAST WORD TO KEEP
	HRLM	T3,(T4)		;[514] MAKE THAT THE HIGHEST ADDR WE'RE MANAGING
	HLLZS	(T1)		;[514] UNLINK LAST BLOCK AS PRELUDE TO SHRINKING
;	JRST	FUNCB3		;[514] NOW GO TRY TO SHRINK

;HERE WHEN WE'RE READY TO TRY TO SHRINK. IF ENTIRE MANAGED AREA WENT AWAY, WE
;MIGHT BE ABLE TO SQUEEZE OUT SOME MORE CORE. BUT IF A SORT IS IN PROGRESS, JUST
;UPDATE ALL RELEVENT POINTERS AND DON'T RETURN THE CORE. ACS:
;	(T4) = ADDR OF HL???. BLOCK.

FUNCB3:	HLRZ	T1,(T4)		;[514] GET HIGHEST ADDR WE'RE MANAGING
	HRRZ	T2,(T4)		;[514] GET LOWEST ADDR WE'RE MANAGING
	CAIL	T1,(T2)		;[514] HIGHEST .LT. LOWEST?
	JRST	FUNCB4		;[514] NO--JUST FREE TO ADDR IN T1
	SETZM	(T4)		;[514] YES--WE JUST EMPTIED AN ENTIRE AREA
	CAIE	T4,HLOVL.##	;[514] ARE WE WORKING IN THE OVERLAY AREA?
	JRST	FUNCB4		;[514] NO--JUST FREE TO ADDR IN T1
	HRRZ	T1,.JBFF##	;[514] YES--FREE ONLY TO C(.JBFF)-1
	SUBI	T1,1		;[514]   ..
FUNCB4:	CAIE	T4,HLOTC.##	;[514] ARE WE WORKING IN THE OTS AREA?
	JRST	FUNCB5		;[514] NO--WE ARE ALL SET TO SHRINK
	HRRZM	T1,.JBFF##	;[514] YES--FIX UP NEW .JBFF
	AOS	.JBFF##		;[514]   BUT MAKE SURE IT'S FIRST-FREE STYLE
				;[514] GO FREE SOME CORE
FUNCB5:
IFE TOPS20,<
;HERE AT LAST TO RETURN SOME CORE TO THE MONITOR. IF PAGING EXISTS (PAGE. UUO),
;THEN KILL THE PAGES OFF MANUALLY TO PRESERVE ANY 'FLOATING' LOW SEGMENT PAGES.
;OTHERWISE JUST USE A GOOD OLD CORE UUO. ACS:
;	(T1) = ADDR OF LAST WORD WE WANT TO KEEP. C(.JBREL) IS END OF AREA WE WILL RETURN.

	HRLZI	T2,.PAGCA	;[514] SIMPLE FUNCTION TO TEST WHETHER
	PAGE.	T2,		;[514]   PAGE. UUO EXISTS HERE
	  JRST	FUNCB8		;[514] DOESN'T--GO USE CORE UUO
	LSH	T1,-^D9		;[514] DOES--TURN ADDR INTO ITS PAGE NUMBER
	ADD	T1,[PA.GAF!1]	;[514] SET DESTROY FUNC AND DON'T KILL THIS PAGE
	HRRZ	T2,.JBREL##	;[514] GET LAST PAGE TO KILL
	LSH	T2,-^D9		;[514]   ..
FUNCB9:	MOVSI	T3,-17		;[514] -<<LENGTH OF PAGTBL>-1>
FUNCB6:	CAIGE	T2,(T1)		;[514] SCANNED ALL PAGES YET?
	JRST	FUNCB7		;[514] YES--GO PROCESS LAST PARTIAL BLOCK
	MOVEM	T1,PAGTBL##+1(T3) ;[514] NO--STORE NEXT PAGE NUMBER IN BLOCK
	ADDI	T1,1		;[514] ADVANCE TO NEXT PAGE
	AOBJN	T3,FUNCB6	;[514] LOOP 'TIL BLOCK FILLS UP
	HRRZM	T3,PAGTBL##	;[514] BLOCK FULL--PROCESS IT
	MOVE	T4,[.PAGCD,,PAGTBL##] ;[514]   ..
	PAGE.	T4,		;[514]   ..
	  TRN			;[514] WE TRIED
	JRST	FUNCB9		;[514] GO FILL BLOCK AGAIN

;WE MAY HAVE A PARTIAL BLOCK OF PAGE-DESTROY REQUESTS TO FINISH.

FUNCB7:	TRNN	T3,-1		;[514] ANYTHING LEFT OVER IN BLOCK?
	JRST	FUNST0		;[514] NO--ALL DONE
	HRRZM	T3,PAGTBL##	;[514] PROCESS THE LEFT-OVERS
	MOVE	T4,[.PAGCD,,PAGTBL##] ;[514]   ..
	PAGE.	T4,		;[514]   ..
	  TRN			;[514] WE TRIED
	JRST	FUNST0		;[514] ALL DONE

FUNCB8:
>;END IFE TOPS20

;DON'T HAVE PAGE. UUO--USE CORE UUO.

	CORE T1,		;[514] SHRINK
	  TRN			;[514] WE TRIED
	JRST	FUNST0		;[514] ALL DONE

SUBTTL	FUNCTIONS RRS/WRS -- MANIPULATE RETAIN/FREE STATUS

;CALL:	MOVEI	16,[ARGBLK]
;	PUSHJ	17,FUNCT.
;
;ARG1(RRS):	INPUT IGNORED, OUTPUT=# OF RECS RETAINED BY OTS
;ARG2(RRS):	IGNORED
;
;ARG1(WRS):	# OF RESOURCES RETAINED BY DBMS
;ARG2(WRS):	IGNORED
;
;STATUS:	0 ALWAYS

FUNRRS:
	PUSHJ	P,FUNRG1	;LOCATE 1ST ARG
	MOVE	T1,SU.RR##	;SET BY LSU
	MOVEM	T1,0(P1)	;RETURN IT TO CALLER
	JRST	FUNST0		;ALWAYS RETURN SUCCESS

FUNWRS:
	PUSHJ	P,FUNRG1
	MOVE	T1,0(P1)	;THIS TIME, SET THE LIBOL VAR
	MOVEM	T1,SU.DBR##	;I.E. DATA BASE RETAINS
	JRST	FUNST0

SUBTTL	USEFUL FUNCTIONS
;.SAVE -- SUBROUTINE TO SAVE ALL USED ACCS EXCEPT T0 AND T1
;CALL:	PUSHJ	P,.SAVE
;RETURN POPJ RESTORES ALL ACCS SAVED

.SAVE:	EXCH	T2,(P)		;SAVE T2, GET CALLER PC
	PUSH	P,T3		;SAVE T3
	PUSH	P,T4		;SAVE T4
	PUSH	P,T5		;SAVE T5
	PUSH	P,P1		;SAVE P1
	PUSH	P,.+3		;SAVE RETURN POINT
	HRLI	T2,-4(P)	;GET ADDRESS WHERE T2 IS SAVED
	JRA	T2,(T2)		;RETURN, RESTORING T2
	CAI	.		;JUST RETURN
	POP	P,P1		;RESTORE P1
	POP	P,T5		;RESTORE T5
	POP	P,T4		;RESTORE T4
	POP	P,T3		;RESTORE T3
	POP	P,T2		;RESTORE T2
	POPJ	P,		;RETURN

	SUBTTL MORMEM -- OTS MEMORY EXPANSION ROUTINE

	COMMENT /*************************

	FUNCTION:
		WHEN THERE IS NOT ENOUGH MEMORY ON THE OTS FREE LIST,
		THIS ROUTINE IS CALLED TO ACQUIRE THE MEMORY BY ADJUSTING
		.JBFF AND .JBREL.   ONCE ACQUIRED, THE FREE MEMORY IS
		PUT ONTO THE FREE LIST (VIA A CALL TO RADLST) AND THUS
		A SUCCESSFUL EXECUTION OF THIS ROUTINE SHOULD BE FOLLOWED
		BY SETTING UP THE ARGUMENTS FOR AND CALLING CORLST.

		THIS ROUTINES CHECKS FOR THE OVERLAY BOUNDRY AND WILL
		NOT ALLOW MEMORY TO BE ALLOCATED ABOVE IT.


	CALL:
		PUSHJ  P,MORMEM

	ENTRY CONDITIONS:

		(T5) = SIZE OF AREA WANTED

	EXIT CONDITIONS:

		(T1) (T2) (T3) DESTROYED
		(T4) (T5)      DESTROYED

	RETURNS:
		CALL +1   NOT ENOUGH MEMORY AVAILABLE
		CALL +2   BAD ERROR -- COULD NOT RELEASE NEW MEMORY
		CALL +3   MEMORY ACQUIRED AND PUT ON OTS FREE LIST,
				IT IS APPROPRIATE TO RESTART THE
				ENTIRE PROCESS (CALLING CORLST)

	**********************/

MORMEM:	;  MEMORY NOT AVAILABLE ON CORLIST--ADD MORE TO IT

	HRRZ	T4,.JBFF	;FIRST FREE LOCATION AVAILABLE
	MOVEI	T3,(T4)		;PLACE 'WORKING' VALUE HERE
	ADDI	T3,(T5)		;COMPUTE NEXT FREE STARTING AREA
	SKIPE	T2,HLOVL.##	;IF OVERLAY AREA ESTABLISHED
	 CAIL	T3,(T2)		;  AND THIS TAKES SOME OF SPACE
	  JUMPN	T2,CPOPJ1	;   THEN GIVE ERROR RETURN

	MOVEI	T5,-1(T3)	;COMPUTE LAST LOCATION DESIRED
	CAMG	T5,.JBREL	;IF WE CAN PROVIDE THIS
	 JRST	MORM50		;  THEN DO NOT EXPAND FURTHER
	MOVEI	T1,(T5)		;  ELSE SAVE ENDING VALUE AND
	CORE	T1,		;       TRY A GET SOME MORE MEMORY.
	 POPJ	P,		;COULD NOT GET MEMORY -- ERROR RETURN

MORM50:
	SKIPN	HLOTC.##	;IF CORE TABLE NOT SET UP YET
	 HRRM	T4,HLOTC.##	; THEN LOWER BOUND IS CURRENT (.JBFF)
	HRLM	T5,HLOTC.##	;UPPER BOUND IS NEW VALUE.
	HRRM	T3,.JBFF	;NEW FIRST FREE LOCATION.
	MOVEI	T1,OTCPT.##	;SET UP THE ADDRESS OF THE FREE LIST
	PUSHJ	P,RADLST	; AND FREE THIS MEMORY.
	  JRST	CPOPJ1		;COULD NOT FREE IT --THIS IS REAL TROUBLE.
	AOS	(P)		;DO DOUBLE SKIP WHEN OK.
CPOPJ1: AOS	(P)		;  DO SINGLE SKIP WHEN INTO OVERLAY AREA.
CPOPJ:	POPJ	P,

SUBTTL	XPAND - CORE ROUTINE

COMMENT \*************************

CALL:
	PUSHJ	P,XPAND

ENTRY CONDITIONS:

	(T5) = ADDRESS OF HIGHEST LOCATION WANTED.

EXIT CONDITIONS:

	(T1), (T2), (T3)	DESTROYED
	(T4), (T5)		UNCHANGED

	IF WE GOT THE CORE IT IS NOW LINKED INTO THE FREE CORE LIST
AND WE RETURN TO CALL+1.
	IF WE DIDN'T GET THE CORE WE RETURN TO FUNST1.

***********************\

XPAND:	PUSH	P,T4		;SAVE T4
	PUSH	P,T5		; AND T5.

;ASK FOR MORE CORE.
	MOVE	T4,.JBREL##	;GET THE CURRENT END OF CORE.
	CAIL	T4,(T5)		;DO WE REALLY NEED TO ASK?
	JRST	XPAND3		;NO, THEN DON'T.
	CORE	T5,		;ASK FOR IT.
	  JRST	XPAND4		;HE WON'T GIVE IT TO US.

;WE GOT THE CORE.
	HLRZ	T4,HLOVL.##	;END OF WHAT WE HAD.
	MOVEI	T4,1(T4)	;START OF WHAT WE GOT.
	MOVE	T5,(P)		;END OF WHAT WE GOT.
XPAND1:	HRRZI	T1,CORPT.##	;GET THE POINTER TO THE FREE CORE LIST.
	PUSHJ	P,RADLST	;GO LINK IT IN THE FREE CORE LIST.
	JRST	XPAND4		;CAN'T. OH BOY, ARE WE IN TROUBLE.
	HRLM	T5,HLOVL.##	;ADJUST HLOVL. TO POINT AT THE NEW END
				; OF FREE CORE.
	POP	P,T5		;RESTORE T5 AND
	POP	P,T4		; T4.
	POPJ	P,		;RETURN.

;COME HERE IF THE CORE IS ALREADY THERE BUT NOT IN THE OVERLAY AREA.

XPAND3:	MOVEI	T5,(T4)		;LAST LOC.
	HLRZ	T4,HLOVL.##	;FIRST LOC LESS 1.
	AOJA	T4,XPAND1	;GO LINK IT IN.

;COME HERE IF WE CAN'T GET THE CORE.

XPAND4:	POP	P,T5		;RESTORE T5 AND
	POP	P,T4		; T4.
	POP	P,T3		;GET RID OF THE RETURN ADR.
	JRST	FUNST1		;RETURN AN ERROR STATUS.

SUBTTL	ROUTINES TO SET UP AND CHECK ARGS FOR GET AND RETURN CORE ROUTINES.

COMMENT	\************************

CALL:
	PUSHJ	P,G2ARGS

ENTRY CONDITIONS:

	NONE.

EXIT CONDITIONS:

	(T0) = STATUS.
	(T1), (T2), (T3)	UNCHANGED
	(T4) = ADDRESS OF FIRST LOCATION WANTED.
	(T5) = ADDRESS OF LAST LOCATION WANTED.

	RETURN IS ALWAYS TO CALL+1.

***********************\

G2ARGS:	SETZI	T0,		;CLEAR THE STATUS.
	PUSHJ	P,FUNRG1	;LOCATE FIRST ARGUMENT
	SKIPLE	T4,0(P1)	;LOAD ADDRESS WANTED
	TLNE	T4,-1		;POSITIVE 18 BITS ADDRESS
	JRST	FUNST3		;ILLEGAL ARGUMENT
	PUSHJ	P,FUNRG2	;LOCATE SECOND ARGUMENT
	MOVM	T5,0(P1)	;LOAD SIZE WANTED - MAY BE NEGATIVE
				; BECAUSE OF THE FORTRAN HACK.
	MOVEM	T5,0(P1)	;TELL THE CALLER HOW MUCH YOU ARE
				; GOING TO GIVE HIM.
	ADDI	T5,-1(T4)	;COMPUTE LAST BLOCK ADR
	TLNE	T5,-1		;GREATER THAN 256 K
	JRST	FUNST3		;ILLEGAL ARGUMENT
	POPJ	P,		;RETURN.

COMMENT	\************************

CALL:
	PUSHJ	P,R2ARGS

ENTRY CONDITIONS:

	(T1) = UPPER LIMIT,,LOWER LIMIT

EXIT CONDITIONS:

	(T0) = STATUS
	(T1)			DESTROYED
	(T2), (T3)		UNCHANGED
	(T4) = ADDRESS OF FIRST LOCATION TO BE RETURNED.
	(T5) = ADDRESS OF LAST LOCATION TO BE RETURNED.

	RETURN IS ALWAYS TO CALL+1.

***********************\

R2ARGS:	SETZI	T0,		;CLEAR THE STATUS.
	PUSHJ	P,FUNRG1	;LOCATE FIRST ARGUMENT
	SKIPLE	T4,0(P1)	;LOAD CORE ADR
	TLNN	T4,-1		;POSITIVE 18 BIT ADDRESS
	CAIGE	T4,(T1)		;LEAGAL ADDRESS
	MOVEI	T0,3		;ILLEGAL ARGUMENT
	PUSHJ	P,FUNRG2	;LOCATE SECOND ARGUMENT
	SKIPLE	T5,0(P1)	;LOAD CORE SIZE
	TLNE	T5,-1		;POSITIVE 18 BIT ADDRESS
	JRST	FUNST3		;ILLEGAL ARGUMENT
	HLRZ	T1,T1		;LOAD LAST LEGAL ADR
	ADDI	T5,-1(T4)	;COMPUTE LAST ADR IN BLOCK
	TLNN	T5,-1		;POSITIVE 18 BIT ADDRESS
	CAILE	T5,0(T1)	;LEGAL ADDRESS
	JRST	FUNST3		;ILLEGAL ARGUMENT
IFN TOPS20,<			;DELETE THE PAGE IF WHOLE PAGE BEING RETURNED
	TRNE	T4,777		;SKIP IF STARTS AT PAGE BOUNDARY
	 POPJ	P,		;NO, JUST RETURN
	TRC	T5,777		;SEE IF ENDS AT PAGE BOUNDARY
	TRCE	T5,777
	 POPJ	P,		;NO, JUST RETURN
	PUSH	P,1		;SAVE ACS USED BY PMAP
	PUSH	P,2
	PUSH	P,3
	SETO	1,		;-1 TO REMOVE PAGES
	MOVE	2,T4		;GET STARTING ADDRESS
	LSH	2,-^D9		;FIND STARTING PAGE NUMBER
	HRLI	2,.FHSLF	;PROCESS HANDLE
	MOVE	3,0(P1)		;GET SIZE TO RETURN
	LSH	3,-^D9		;CONVERT TO # OF PAGES
	TXO	3,PM%CNT	;SPECIFY REPEAT COUNT
	PMAP%			;REMOVE THE PAGES..
	 ERJMP	.+1		;IGNORE ERRORS
	POP	P,3		;RESTORE ACS USED BY PMAP
	POP	P,2
	POP	P,1
>;END IFN TOPS20
	POPJ	P,		;RETURN.

SUBTTL	ARGBLK MANIPULATION ROUTINES

;FUNADR - RETURN ADR OF ARGUMENT
;CALL:	MOVEI	P1,OFFSET IN ARGBLK
;	PUSHJ	P,FUNADR
;	(RETURN)
;
; RETURN ADR IN P1
;
FUNRG2:	SKIPA	P1,FUNAD1	;LOAD ARG2 OFFSET
FUNRG1:	MOVEI	P1,FN.RG1	;LOAD ARG1 OFFSET
FUNADR:	ADDI	P1,(L)		;OFFSET ARGBLK
	MOVE	P1,@P1		;GET ADDRESS
FUNAD1:	POPJ	P,FN.RG2	;RETURN


SUBTTL	ROUTINES TO SET THE STATUS AND RETURN.

FUNST0:	TDZA	T0,T0		;SET STATUS 0
FUNST2:	MOVEI	T0,2		;SET STATUS 2
	POPJ	P,		;RETURN

FUNST3:	MOVEI	T0,3		;SET STATUS 3
	POPJ	P,		;RETURN

	END