COMMENT * SIMULA specification;
OPTIONS(/E:QUICK,search);
INTEGER PROCEDURE search(master,config);
TEXT master,config;

COMMENT Starting at master.Pos, search looks for a subtext of master = config.
If such a subtext is found, SEARCH gives Pos of the first character, i e
master.Sub(search(master,config)-1,config.Length) is the subtext sought,
otherwise SEARCH returns master.Length+1.
;

!*;! MACRO-10 code !*;!

	TITLE search
	ENTRY search
	SUBTTL	SIMULA utility, Lars Enderin Nov 1975

;!*** Copyright 1975 by the Swedish Defence Research Institute. ***
;!*** Copying is allowed.					***

;! Last Edit: [125], 1976-06-21/LE

	sall
	search	simmac,simmcr,simrpa
	macinit

;! Local definitions ;!

	master==XWAC1
	s==master		;! Local copy
	config==XWAC3
	cfp==config
	c1==cfp+1	;! To hold first character of config
	ls==s+1		;! (Remaining) length of master
	lc==XIAC	;! Length of config
	xa==XWAC6	;! Work ac, usually word address in master
	sp==xa
	xb==XWAC7	;! Work ac
	sp1==xb
	ls1==XWAC10	;! Work ac, remaining characters at start of initial
			;! match in master
	cfp1==XWAC11

search:	PROC
	IF	;! Top ac is not XWAC1
		CAIN	XTAC,XWAC1
		GOTO	FALSE
	THEN	;! Save ac's
		nn==0
		repeat	4,<
		EXCH XWAC1+nn,nn(XTAC)
		nn==nn+1
		>
	FI
	SAVE	<cfp1,c1,sp,sp1,ls1,ls,lc>
	STACK	XTAC
	LF	lc,ZTVLNG(,config)

	STACK	XWAC1		;! Place text descr in stack
	HRRZ	s,XPDP
	STACK	XWAC2
	LF	ls,ZTVLNG(s)	;! s.Length
	JUMPE	lc,L8		;! config.Length=0
	LF	X1,ZTVCP(s)
	SUBI	ls,(X1)		;! rest(s).Length
	SETO	ls1,		;! remaining length-1 at match:=-1
	CAIGE	ls,(lc)
	GOTO	nomatch		;! if config too long to fit

	;! Compute byte pointers for CONFIG and MASTER
	LF	sp,ZTVSP(,config)
	IF	;! config starts at beginning of config.Main
		JUMPN	sp,FALSE
	THEN	;! Convert directly to byte pointer
		ADD	cfp,ptab+1
	ELSE	;! Compute via word and byte offsets
		IDIVI	sp,5
		ADDI	cfp,2(sp)
		HLL	cfp,ptab+1(sp+1)
	FI

	LF	sp,ZTVSP(s)	;! startpos(s)-1
	SETZ	sp1,
	ADDI	sp,(X1)		;! + s.Pos-1
	IF	;! Non-zero effective offset
		JUMPE	sp,FALSE
	THEN
		IDIVI	sp,5	;! sp1:=offset in first word
	FI
	ADD	sp,(s)		;! Address of first word to consider
	ADDI	sp,2
	HLL	sp,ptab(sp1)	;! Create byte pointer for master
	LDB	c1,cfp		;! c1:=config.Getchar

L1():!	SUBI	ls,-1(lc)
	LOOP	;! Through initial characters of master
		SOJL	ls,nomatch
		ILDB	sp
	AS
		CAIE	(c1)
		GOTO	TRUE
	SA

	;! c1 matched a character of master here
	;! Now check following characters if any

	ADDI	ls,-1(lc)
	LI	ls1,(ls)		;! Remember 1st match
	L	sp1,sp
	LI	x2,(lc)
	L	cfp1,cfp
	LOOP	;! Matching characters from config and master
		SOJLE	X2,fullmatch
		ILDB	X1,cfp1
		SOJL	ls,nomatch
		ILDB	sp
	AS
		CAIN	(X1)
		GOTO	TRUE
	SA
	LI	ls,(ls1)
	L	sp,sp1
	SETZ	ls1,
	GOTO	L1

nomatch:SETO	ls1,
fullmatch:
	LF	,ZTVLNG(s)
	SUBI	1(ls1)
	SF	,ZTVCP(s)
L8():!	LF	XWAC1,ZTVCP(s)
	SUB	XPDP,[2,,2]	;! Remove text descr from stack
	ADDI	XWAC1,1
	UNSTK	XTAC
	RESTORE
	IF	;! Xtop is not XWAC1
		CAIN	XTAC,XWAC1
		GOTO	FALSE
	THEN	;! Restore ac's
		nn==4
		repeat	4,<
		nn==nn-1
		EXCH	XWAC1+nn,nn(XTAC)
		>
	FI
	POPJ	XPDP,
	EPROC
ptab:	POINT	7,2,-1
	POINT	7,2,6
	POINT	7,2,13
	POINT	7,2,20
	POINT	7,2,27
	POINT	7,2,34	;! [125]
	END;