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;[SRI-NIC]SRC:<MM-NEW>HSTNAM.MAC.90,  4-Sep-87 15:51:33, Edit by MKL
; merge DHSTNM into new HSTNAM module
;[SRI-NIC]SRC:<MM-NEW>DHSTNM.MAC.6, 11-Aug-87 14:58:14, Edit by MKL
; if temporary GTDOM% failure, return success but host number zeroed
;[SRI-NIC]SRC:<MM-NEW>DHSTNM.MAC.2, 18-Jun-87 00:05:42, Edit by MKL
; change all GTHST% to GTDOM%
;[SRI-NIC]SRC:<MM-NEW>HSTNAM.MAC.87, 31-Aug-87 14:05:29, Edit by MKL
; Remove  Crispins "#Internet" bullshit

	TITLE DHSTNM TOPS-20 host name lookup routines
	SUBTTL Written by Mark Crispin - December 1982

; Copyright (C) 1982, 1983, 1984, 1985, 1986 Mark Crispin
; All rights reserved.
;
;  This software, in source and binary form, is distributed free of charge.
; The binary form of this software may be incorporated into public-domain
; software and the source may be used for reference purposes.  Copies may
; be made of the source provided this copyright notice is included.  Wholesale
; copying of the routines in this software or usage of this software in a
; proprietary product without prior permission is prohibited.

;  This module is an attempt to provide a common and consistant host name/host
; address lookup interface for all network software.  For the most part, these
; modules have been designed like jsi.  They take their arguments in AC's in a
; fairly consistant manner.  Only the documented returned value AC's are
; changed; everything else is unaffected.  Note that in a failure return the
; returned value AC's are undefined; software should not be written to assume
; any side-effects of a failure as this may change from release to release.
;
;  The only real difference from a JSYS is that since these are subroutines
; invoked by CALL and use the stack any stack references (e.g. STKVAR) must be
; made absolute prior to using the routines.  For example, assuming FOOSTR is
; a string in a STKVAR:
;  Wrong:
;	MOVE A,[POINT 7,FOOSTR]
;	CALL $xxxxx
;  Right:
;	HRROI A,FOOSTR
;	CALL $xxxxx
;
;  In addition to the individual routines for each network, there are also
; global routines allowing name/address lookups for multiple networks.  In
; general, software should be written to use the global routines rather than
; a specific network's routine if there is any possibility that software will
; ever be used for more than one network.  The additional generality gained
; costs nothing but a minor bit of discipline on the part of the programmer
; and will save future programmers much grief.
;
;  One firm rule: absolutely NO software should do host lookups without going
; through this module.  In particular, no software should be written to access
; "host tables" (e.g. SYSTEM:HOSTSn.BIN).  Any software which knows about the
; format, or depends upon existance, of host tables is guaranteed to break
; without warning.
;
;  This module tries to be "internet" (not to be confused with Internet).  In
; order to provide a means of specifying an explicit name registry, top-level
; domains prefixed with an "#" are used.  These are relative domains, not to
; be confused with Internet domains which are absolute.  Eventually, absolute
; addressing will come into being, but at present that requires considerably
; more cooperation from the various networks than is presently forthcoming.

; Definitions

	SEARCH MACSYM,MONSYM	; system definitions
	SALL			; suppress macro expansions
	.DIRECTIVE FLBLST	; sane listings for ASCIZ, etc.

IFNDEF FTGTHBUG,<FTGTHBUG==1>	; -1 => compensate for .GTHSN GTHST% bug which
				;  sometimes returns 1200,,0 if no such host
IFNDEF HSTNML,<HSTNML==^D64>	; length of a host name (64 required minimum)
 HSTNMW==<HSTNML/5>+1		; host name length in words

; AC definitions

A=:1				; JSYS, temporary AC's
B=:2
C=:3
D=:4
P=:17				; stack pointer

	.PSECT CODE		; enter pure CODE PSECT

; $GTPRO - Get host address and find protocol supported by host
; Accepts:
;	A/ host name string
;	C/ pointer to protocol list or -1 to try all supported protocols
;	CALL $GTPRO
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B,
;			protocol address in C
;
;  The protocol list is in the form:
;	[ASCIZ/protocol1/],,data1
;	[ASCIZ/protocol2/],,data2
;		...
;	[ASCIZ/protocoln/],,datan
;	0			; end of table

$GTPRO::SAVEAC <D>
	STKVAR <HSTPTR,HSTPRO>
	TXC A,.LHALF		; is source LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; save pointer
	IFL. C			; user want all known protocols?
	  MOVEI C,PROTBX	; yes, use our internal table
	  MOVX D,NPROTS		; number of protocols to try
	ELSE.
	  SETZ D,		; otherwise will scan until empty field
	ENDIF.
	MOVEM C,HSTPRO		; save current protocol pointer
	DO.
	  SKIPN B,@HSTPRO	; get protocol entry
	   RET			; end of list, return failure
	  HLROS B		; make string pointer to name
	  MOVEI A,PRORTS	; our known table
	  TBLUK%		; see if can find entry in table
	   ERJMP R		; strange failure
	  IFXE. B,TL%NOM!TL%AMB	; found this protocol in table?
	    HRRZ B,(A)		; yes, get pointer to routines to call
	    HRRZ B,(B)		; get address/string routine
	    MOVE A,HSTPTR	; get pointer to host name
	    CALL (B)		; see if name known under this protocol
	    IFSKP.
	      MOVE C,HSTPRO	; found it, get protocol pointer in C
	      RETSKP		; return success
	    ENDIF.
	  ENDIF.
	  AOS HSTPRO		; not found here, bump current pointer
	  SOJN D,TOP.		; else try for next
	ENDDO.

; $GTNAM - Get name of host given its protocol
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	C/ protocol list item pointer
;	CALL $GTNAM
; Returns +1: Failed
;	  +2: Success, updated pointer in A
;
;  For compatibility with the $GTPRO call and the possible convenience of
; applications programs, a negative argument ("try all protocols") is allowed
; in C.  However, this is only valid if B is also negative ("local host")
; since different networks have different addressing conventions.  If this is
; the case, $GTNAM becomes $GTLCL.

$GTNAM::IFL. C			; caller want to try all protocols?
	  JUMPL B,$GTLCL	; yes, use $GTLCL if local host desired
	  RET			; else fail, meaningless call
	ENDIF.
	SAVEAC <C>
	STKVAR <HSTPTR,HSTNUM>
	TXC A,.LHALF		; is destination pointer's LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; save pointer
	MOVEM B,HSTNUM		; save host address
	MOVEI A,PRORTS		; table of known protocols
	HLRO B,(C)		; protocol to look up
	TBLUK%			; see if can find entry in table
	 ERJMP R		; strange failure
	JXN B,TL%NOM!TL%AMB,R	; fail if protocol not found in table?
	HRRZ C,(A)		; get pointer to routines to call
	HLRZ C,(C)		; get string/address routine
	MOVE A,HSTPTR		; get pointer to host name
	MOVE B,HSTNUM
	CALLRET (C)		; see if name known under this protocol

; $GTLCL - Get name of local host
; Accepts:
;	A/ pointer to destination host string
;	CALL $GTLCL
; Returns +1: Failed (shouldn't happen)
;	  +2: Success, with updated pointer in A

$GTLCL::SAVEAC <B,C,D>
	STKVAR <HSTPTR,HSTNUM,<HSTSTR,HSTNMW>,TMPJFN>
	TXC A,.LHALF		; is destination pointer's LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; save pointer
	MOVSI D,-NPROTS
	DO.
	  MOVEI A,PRORTS	; look up protocol
	  HLRO B,PROTAB(D)	; protocol to look up
	  TBLUK%
	   ERJMP R		; strange failure
	  JXN B,TL%NOM!TL%AMB,R	; very strange if protocol not found
	  HRRZ C,(A)		; get pointer to routines to call
	  HLRZ C,(C)		; get address/string routine
	  MOVE A,HSTPTR		; pointer to destination string
	  SETO B,		; translate local host
	  CALL (C)		; see if we're known under this protocol
	  IFSKP.
	    RETSKP		; we are, return success
	  ENDIF.
	  AOBJN D,TOP.		; try next protocol
	ENDDO.
	MOVX A,GJ%SHT!GJ%OLD	; try for the local hostname file
	HRROI B,[ASCIZ/SYSTEM:HOSTNAME.TXT/]
	GTJFN%			; find system file with our name
	IFNJE.
	  MOVEM A,TMPJFN	; save JFN in case OPENF% failure
	  MOVX B,<<FLD 7,OF%BSZ>!OF%RD> ; open in 7-bit ASCII
	  OPENF%
	  IFNJE.
	    HRROI B,HSTSTR	; read in host name
	    MOVX C,HSTNML	; up to this many characters
	    MOVX D,.CHLFD	; terminate on a linefeed
	    SIN%
	     ERJMP .+1
	    CLOSF%		; close off file
	     ERJMP .+1
	    MOVE A,[POINT 7,HSTSTR] ; now process string a bit
	    DO.
	      ILDB B,A		; get byte from string read in
	      CAIE B,.CHLFD	; LF terminates
	       CAIN B,.CHCRT	; CR terminates
		SETZ B,
	      CAIE B,.CHTAB	; TAB terminates
	       CAIN B,.CHSPC	; space terminates
		SETZ B,
	      IDPB B,HSTPTR	; return byte to user
	      JUMPN B,TOP.	; if null, done
	    ENDDO.
	    MOVE A,HSTPTR	; return updated pointer
	    RETSKP
	  ELSE.
	    MOVE A,TMPJFN	; get back JFN we got
	    RLJFN%		; free it
	     ERJMP R		; not interested in errors here
	    RET
	  ENDIF.
	ENDIF.
	MOVE A,HSTPTR		; destination
	HRROI B,[ASCIZ/TOPS-20/] ; default name string
	SETZ C,			; no limit
	SOUT%			; copy the string
	 ERJMP R		; can't fail
	RETSKP

; Table of known protocols and their dispatches

DEFINE DN (NAME,ADRNAM,NAMADR) <
 [ASCIZ/'NAME'/],,['ADRNAM',,'NAMADR']
>;DEFINE DN

PRORTS:	NPROTS,,NPROTS
	DN Chaos,$CHSNS,$CHSSN	; Chaosnet
	DN DECnet,$DECNS,$DECSN	; DECnet
	DN Pup,$PUPNS,$PUPSN	; Pup Ethernet
	DN Special,$SPCNS,$SPCSN ; Special external network
	DN TCP,$GTHNS,$GTHSN	; TCP/IP Internet
NPROTS==<.-PRORTS>-1

;  Similar, but in $GTPRO protocol list format in "preferred" order for name
; registration lookup.  Note that this is not necessarily the same as the
; "preferred" order for communications.  In particular, TCP comes first since
; Internet registry is the closest thing to a universal registry there is and
; any non-Internet networks which communicate with Internet are expected to
; comprehend and obey Internet's conventions.
;  *** IMPORTANT: The mailer depends upon Internet being the preferred
; registry in this table.  In particular, it knows that $GTLCL will return
; the Internet registry if the local host is on Internet.

DEFINE DP (NAME) <
 [ASCIZ/'NAME'/],,0
>;DEFINE DP

;  PROTBX is for $GTPRO's list of all hosts.  The Special network always
; overrides any other registries in this case.  This allows use of the
; Special network to do custom delivery to a defined host, and also prevents
; lossage when some random foreign host comes up with the same name.
PROTBX:	DP Special
PROTAB:	DP TCP
	DP Pup
	DP Chaos
	DP DECnet
	DP Special
IFN <.-PROTAB>-NPROTS,<PRINTX ?PROTAB/PRORTS length mismatch
	PASS2
	END
>
	0			; terminate for $GTPRO

; $GTCAN - Get canonical name for host
; Accepts:
;	A/ host name string
;	B/ destination host name string
;	C/ pointer to protocol list or -1 to try all supported protocols
;	CALL $GTCAN
; Returns +1: Failed
;	  +2: Success, updated destination pointer in A, host address in B,
;			protocol address in C

repeat 0,<
$GTCAN::STKVAR <HSTPTR,hstsav,hstspr>
	MOVEM B,HSTPTR		; save destination pointer
	CALL $GTPRO		; get host address per protocol
	 RET			; fails
	MOVE A,HSTPTR		; get destination pointer
	CALL $GTNAM		; translate to canonical name
	 RET			; shouldn't ever fail
	RETSKP			; success
>
;;; Domain support
$GTCAN::SAVEAC <D>
	STKVAR <SRCPTR,HSTPTR>
	MOVEM A,SRCPTR
	MOVEM B,HSTPTR		; save destination pointer
	CALL $GTPRO		; get host address per protocol
	 RET			; fails
	MOVE A,HSTPTR		; get destination pointer
	IFE. B			;was domain name unavailable ?
	 MOVE B,SRCPTR		; yes: assume name was correct as is
	 PUSH P,C
	 SETZB C,D
	 SOUT%
	 SETZ B,
	 POP P,C
	ELSE.
	 CALL $GTNAM		; translate to canonical name
	  RET			; shouldn't ever fail
	ENDIF.
	RETSKP			; success

	ENDSV.

; $GTHNS - Translate Internet host address to host name
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	CALL $GTHNS
; Returns +1: Failed
;	  +2: Success, updated pointer in A

$GTHNS::SAVEAC <C,D>
	STKVAR <HSTPTR,HSTNUM>
	TXC A,.LHALF		; is string pointer LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; save host pointer
	MOVEM B,HSTNUM		; save host address
	CAME B,[-1]		; want local address?
	IFSKP.
	  MOVX A,.GTHSZ		; yes, get local address so can output
	  GTDOM%		;  bracketed if unnamed local host
	   ERJMP R		; not on Internet
	  MOVEM D,HSTNUM	; set new host address
	ENDIF.
	MOVX A,.GTHNS		; number to name conversion
	MOVE B,HSTPTR		; destination pointer
	MOVE C,HSTNUM		; host address
	GTDOM%
	IFNJE.
	  MOVEM C,HSTNUM	; return host address
	  MOVE A,B		; set up byte pointer for $ADDOM
	ELSE.
	  MOVEI A,"["		; start bracketed number
	  IDPB A,HSTPTR
	  MOVE A,HSTPTR		; get pointer back
	  LDB B,[POINT 8,HSTNUM,11] ; get first byte
	  MOVEI C,^D10		; output host parts in decimal
	  NOUT%			; output it
	   ERJMP R
	  MOVEI D,"."		; delimiting dot
	  IDPB D,A		; add delimiting dot
	  LDB B,[POINT 8,HSTNUM,19] ; get next byte
	  NOUT%			; output it
	   ERJMP R
	  IDPB D,A		; add delimiting dot
	  LDB B,[POINT 8,HSTNUM,27] ; get next byte
	  NOUT%			; output it
	   ERJMP R
	  IDPB D,A		; add delimiting dot
	  LDB B,[POINT 8,HSTNUM,35] ; get final byte
	  NOUT%			; output it
	   ERJMP R
	  MOVEI D,"]"		; terminate bracketed number
	  IDPB D,A
	  move b,a
	  setz d,
	  idpb d,b
	ENDIF.
;	HRROI B,[ASCIZ/#Internet/] ; add Internet domain
;	CALL $ADDOM		; add domain, leave pointer in A
	MOVE B,HSTNUM		; and host address
	RETSKP

; $GTHSN - Translate Internet host name to host address
; Accepts:
;	A/ pointer to host string
;	CALL $GTHSN
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B

$GTHSN::SAVEAC <C,D>		; preserve these
	STKVAR <HSTPTR,HSTNUM,<HSTSTR,HSTNMW>>
	MOVE B,A		; copy string so we can muck with it
	HRROI A,HSTSTR		; into HSTSTR
	MOVX C,HSTNML+1		; up to this many characters
	SETZ D,			; terminate on null
	SOUT%
	 ERJMP R		; percolate failure up to caller
	JUMPE C,R		; string too long if exhausted
	MOVEM B,HSTPTR		; save pointer
	SETO B,			; back pointer up by one
	ADJBP B,HSTPTR
	MOVEM B,HSTPTR		; save updated pointer
;	HRROI A,HSTSTR		; now remove Internet domain
;	HRROI B,[ASCIZ/#Internet/]
;	CALL $RMDOM
	LDB A,[POINT 7,HSTSTR,6] ; get opening character
	CAIE A,"#"		; moby number following?
	IFSKP.
	  MOVE A,[POINT 7,HSTSTR,6] ; set up pointer to number
	  MOVEI C,^D10		; in decimal
	  NIN%			; input number
	   ERJMP R		; failed
	  LDB C,A		; get terminating byte
	  JUMPN C,R		; string has non-numeric text in it
	  RETSKP		; return success
	ENDIF.
	CAIE A,"["		; bracketed host following?
	IFSKP.
	  SETZM HSTNUM		; clear out existing crud in number
	  MOVE A,[POINT 7,HSTSTR,6] ; set up pointer to number
	  MOVEI C,^D10		; in decimal
	  NIN%			; input number
	   ERJMP R		; failed
	  JXN B,<<MASKB 0,27>>,R ; disallow if not 8-bit number
	  DPB B,[POINT 8,HSTNUM,11] ; store byte
	  LDB B,A		; get terminating byte
	  CAIE B,"."		; proper terminator?
	   RET			; return failure
	  NIN%			; input number
	   ERJMP R		; failed
	  JXN B,<<MASKB 0,27>>,R ; disallow if not 8-bit number
	  DPB B,[POINT 8,HSTNUM,19] ; store byte
	  LDB B,A		; get terminating byte
	  CAIE B,"."		; proper terminator?
	   RET			; return failure
	  NIN%			; input number
	   ERJMP R		; failed
	  JXN B,<<MASKB 0,27>>,R ; disallow if not 8-bit number
	  DPB B,[POINT 8,HSTNUM,27] ; store byte
	  LDB B,A		; get terminating byte
	  CAIE B,"."		; proper terminator?
	   RET			; return failure
	  NIN%			; input number
	   ERJMP R		; failed
	  JXN B,<<MASKB 0,27>>,R ; disallow if not 8-bit number
	  DPB B,[POINT 8,HSTNUM,35] ; store final byte
	  LDB B,A		; get terminating byte
	  CAIE B,"]"		; proper terminator?
	   RET			; return failure
	  ILDB B,A		; make sure tied off with null
	  JUMPN B,R
	  MOVE B,HSTNUM		; return host address
	  RETSKP		; return success
	ENDIF.
	MOVX A,.GTHSN		; translate name to number
	HRROI B,HSTSTR		; foreign host name
	GTDOM%
	 ERJMP [TLZ A,-1
		CAIE A,GTDX4	;temporary error?
		 RET		;no, die
		SETZ B,		;yes, so return zero host number
	        JRST .+1]	;continue
	ILDB B,B		; be sure it parsed the whole string
	JUMPN B,R		; it didn't, return failure
	MOVE A,HSTPTR		; get back updated pointer
	MOVE B,C		; get host address in proper AC
IFN FTGTHBUG,<
	CAME B,[1200,,0]	; did GTHST% return this silly value?
	IFSKP.
	  SETZ B,		; return 0 for host address
	  RET
	ENDIF.
>;IFN FTGTHBUG
	RETSKP

; $DECNS - Translate DECnet host address to host name
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	CALL $DECNS
; Returns +1: Failed
;	  +2: Success, updated pointer in A

$DECNS::SAVEAC <C>
	STKVAR <HSTPTR,HSTNUM,<NODBLK,2>>
	TXC A,.LHALF		; is string pointer LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; save destination pointer
	MOVEM B,HSTNUM		; save host "number"
	CAME B,[-1]		; want local address?
	IFSKP.
	  MOVEM A,.NDNOD+NODBLK	; set up string pointer in NODE% block
	  MOVX A,.NDGLN		; get local node name function
	  MOVEI B,NODBLK	; pointer to destination name string
	  NODE%			; get local name
	   ERJMP R		; failed
	  MOVE A,HSTPTR		; now build host "number"
	  CALL $DECSN
	   RET			; NODE%, but no DECnet apparently
	  MOVEM A,HSTPTR	; set as updated host pointer
	  MOVEM B,HSTNUM	; save host "number"
	ELSE.
	  MOVE A,HSTPTR		; get destination string pointer
	  DO.
	    SETZ C,		; prepare for byte
	    ROTC B,6		; get a SIXBIT byte
	    JUMPE C,R		; imbedded space invalid
	    ADDI C,"A"-'A'	; convert to ASCII
	    IDPB C,A		; store in returned string
	    JUMPN B,TOP.	; get next byte
	  ENDDO.
	  MOVE C,A		; tie off string
	  IDPB B,C
	  EXCH A,HSTPTR		; update pointer
	  CALL DCNVFY		; try to verify
	   RET
	ENDIF.
	MOVE A,HSTPTR		; return updated pointer
	HRROI B,[ASCIZ/#DECnet/] ; add DECnet domain
	CALL $ADDOM
	MOVE B,HSTNUM		; and updated "number"
	RETSKP

; $DECSN - Translate DECnet host name to host address
; Accepts:
;	A/ pointer to host string
;	CALL $DECSN
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B

$DECSN::SAVEAC <C,D>
	STKVAR <HSTPTR,HSTNUM,<HSTSTR,HSTNMW>>
	MOVEM A,HSTPTR		; save host pointer
	HRROI A,HSTSTR		; copy string so we can muck with it
	MOVE B,HSTPTR		; get back host pointer
	MOVX C,HSTNML+1		; up to this many characters
	SETZ D,			; terminate on null
	SOUT%
	 ERJMP R		; percolate failure up to caller
	JUMPE C,R		; string too long if exhausted
	MOVEM B,HSTPTR		; save pointer
	SETO B,			; back pointer up by one
	ADJBP B,HSTPTR
	MOVEM B,HSTPTR		; save updated pointer
	HRROI A,HSTSTR		; now remove DECnet domain
	HRROI B,[ASCIZ/#DECnet/]
	CALL $RMDOM
	CALL DCNVFY		; try to verify
	 RET
	SETZM HSTNUM		; now build host "number"
	MOVE B,[POINT 6,HSTNUM]
	DO.
	  ILDB C,A		; get byte of name
	  CAIG C," "		; has a sixbit representation?
	   EXIT.		; no, done
	  CAIL C,"`"		; lowercase?
	   SUBI C,"a"-"A"	; yes, convert to upper case
	  SUBI C,"A"-'A'	; convert to SIXBIT
	  IDPB C,B		; stash in string
	  TLNE B,770000		; at last byte?
	   LOOP.
	ENDDO.
	MOVE A,HSTPTR		; return updated pointer
	MOVE B,HSTNUM		; and updated "number"
	RETSKP

; DCNVFY - Verify DECnet node name (internal routine only)
; Accepts:
;	A/ pointer to node name string
; Returns +1: Failed
;	  +2: Success, name validated

DCNVFY:	SAVEAC <A,B>
	STKVAR <<DCNFIL,40>,DCNJFN,NODPTR,<NODBLK,2>>
	MOVEM A,NODPTR		; save pointer for later
	MOVEM A,.NDNOD+NODBLK	; and in NODE% block
	MOVX A,.NDVFY		; validate node name
	MOVEI B,NODBLK
	NODE%
	 ERJMP R		; syntax invalid
	JN ND%EXM,.NDFLG+NODBLK,RSKP ; validated name
	HRROI A,DCNFIL		; syntax valid, but name not, do extra test
	HRROI B,[ASCIZ/DCN:/]
	SETZ C,
	SOUT%
	MOVE B,NODPTR
	SOUT%
	HRROI B,[ASCIZ/-TASK-DCNVFY-TEST/] ; random task name
	SOUT%
	IDPB C,A		; tie off string with null
	MOVX A,GJ%SHT		; see if we can get that name
	HRROI B,DCNFIL
	GTJFN%
	 ERJMP R		; can't get name, no DECnet or something
	MOVEM A,DCNJFN		; save JFN for later
	MOVX B,OF%RD		; open for read
	OPENF%
	IFNJE.
	  CLOSF%		; won, flush the connection
	   ERJMP .+1
	ELSE.
	  EXCH A,DCNJFN		; get back the JFN, save error code
	  RLJFN%		; free it
	   ERJMP .+1		; ignore error here
	  MOVE A,DCNJFN		; get back error code
	  CAIE A,NSPX18		; was it "No path to node"?
	   RET			; no, no such node then
	ENDIF.
	RETSKP			; return success

	ENDSV.

; $PUPNS - Translate Pup Ethernet host address to host name
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	CALL $PUPNS
; Returns +1: Failed
;	  +2: Success, updated pointer in A

IFNDEF PUPNM%,<
	OPDEF PUPNM% [JSYS 443]

PN%NAM==:1B0
PN%FLD==:1B1
PN%OCT==:1B2
>;IFNDEF PUPNM%

$PUPNS::SAVEAC <C,D>
	STKVAR <HSTPTR,<PUPHSN,2>>
	MOVEM A,HSTPTR		; save host pointer
	CAME B,[-1]		; want local address?
	IFSKP.
	  MOVX A,SIXBIT/PUPROU/	; get GETAB% index of PUPROU table
	  SYSGT%		; B/ -items,,table number
	   ERJMP R		; shouldn't happen
	  JUMPE B,R		; fail if no such table
	  HLLZ C,B		; C/ AOBJN pointer through PUPROU
	  DO.
	    HRR A,B		; table number
	    HRL A,C		; index in table
	    GETAB%		; get table entry
	     ERJMP R		; shouldn't happen
	    IFXE. A,1B0		; network inaccessible?
	      JXN A,.RHALF,ENDLP. ; no, done if have local addr on this network
	    ENDIF.
	    AOBJN C,TOP.	; try next entry
	    RET			; unable to find our host address
	  ENDDO.
	  HRLI B,1(C)		; network # is 1+<PUPROU index>
	  HRR B,A		; host # is in RH of PUPROU entry
	ENDIF.
	MOVEM B,PUPHSN		; save host address argument
	SETZM 1+PUPHSN		; don't want port info
	MOVE A,HSTPTR		; destination string
	MOVX B,PN%FLD!PN%OCT!<FLD 1,.LHALF> ; no defaults, use octal if have to
	HRRI B,PUPHSN		; pointer to host address
	PUPNM%			; call incredibly hairy Pup JSYS
	 ERJMP R		; failed
	HRROI B,[ASCIZ/#Pup/]	; add Pup domain
	CALL $ADDOM
	MOVE B,PUPHSN		; return host number too in case argument -1
	RETSKP

; $PUPSN - Translate Pup Ethernet host name to host address
; Accepts:
;	A/ pointer to host string
;	CALL $PUPSN
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B

$PUPSN::SAVEAC <C,D>
	STKVAR <HSTPTR,<HSTSTR,HSTNMW>,<PUPHSN,2>>
	MOVE B,A		; copy string so we can muck with it
	HRROI A,HSTSTR		; into HSTSTR
	MOVX C,HSTNML+1		; up to this many characters
	SETZ D,			; terminate on null
	SOUT%
	 ERJMP R		; percolate failure up to caller
	JUMPE C,R		; string too long if exhausted
	MOVEM B,HSTPTR		; save pointer
	SETO B,			; back pointer up by one
	ADJBP B,HSTPTR
	MOVEM B,HSTPTR		; save updated pointer
	HRROI A,HSTSTR		; now remove Pup domain
	HRROI B,[ASCIZ/#Pup/]
	CALL $RMDOM
	MOVX B,PN%NAM!<FLD 1,.LHALF> ; lookup name, return one word
	HRRI B,PUPHSN		; pointer to host address
	PUPNM%			; call incredibly hairy Pup JSYS
	 ERJMP R		; failed
	MOVE A,HSTPTR		; return updated pointer
	MOVE B,PUPHSN		; get host address
	RETSKP

; $CHSNS - Translate Chaosnet host address to host name
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	CALL $CHSNS
; Returns +1: Failed
;	  +2: Success, updated pointer in A

IFNDEF CHANM%,<
	OPDEF CHANM% [JSYS 460]

.CHNPH==:0			; return local site primary name and number
.CHNSN==:1			; Chaosnet name to number
.CHNNS==:2			; Chaosnet number to primary name
>;IFNDEF CHANM%

$CHSNS::SAVEAC <C>
	STKVAR <HSTPTR,HSTNUM>
	MOVEM A,HSTPTR		; save host pointer
	MOVEM B,HSTNUM		; save host number
	CAME B,[-1]		; want local address?
	IFSKP.
	  MOVX A,.CHNPH		; return primary name/address
	  MOVE B,HSTPTR		; pointer to string
	  CHANM%
	   ERJMP R		; failed
	  MOVEM A,HSTNUM	; set returned address
	ELSE.
	  MOVX A,.CHNNS		; return name for this address
	  MOVE B,HSTPTR
	  MOVE C,HSTNUM
	  CHANM%
	   ERJMP R		; failed
	ENDIF.
	MOVE A,B		; updated pointer from CHANM% returned in B
	HRROI B,[ASCIZ/#Chaos/]	; add Chaos domain
	CALL $ADDOM
	MOVE B,HSTNUM		; return host number too in case argument -1
	RETSKP

; $CHSSN - Translate Chaosnet host name to host address
; Accepts:
;	A/ pointer to host string
;	CALL $CHSSN
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B

$CHSSN::SAVEAC <C,D>
	STKVAR <HSTPTR,<HSTSTR,HSTNMW>>
	MOVE B,A		; copy string so we can muck with it
	HRROI A,HSTSTR		; into HSTSTR
	MOVX C,HSTNML+1		; up to this many characters
	SETZ D,			; terminate on null
	SOUT%
	 ERJMP R		; percolate failure up to caller
	JUMPE C,R		; string too long if exhausted
	MOVEM B,HSTPTR		; save pointer
	SETO B,			; back pointer up by one
	ADJBP B,HSTPTR
	MOVEM B,HSTPTR		; save updated pointer
	HRROI A,HSTSTR		; now remove Chaos domain
	HRROI B,[ASCIZ/#Chaos/]
	CALL $RMDOM
	MOVX A,.CHNSN		; Chaosnet name to number
	HRROI B,HSTSTR		; foreign host name
	CHANM%
	 ERJMP R
	EXCH A,B		; want pointer in A, address in B
	RETSKP

; $SPCNS - Translate "Special" host address to host name
; Accepts:
;	A/ pointer to destination host string
;	B/ foreign host address
;	CALL $SPCNS
; Returns +1: Failed
;	  +2: Success, updated pointer in A

$SPCNS::SAVEAC <C,D>
	STKVAR <HSTPTR,HSTNUM,<DIRSTR,20>,TOPDIR,NAMPTR>
	MOVEM A,HSTPTR		; save host pointer
	MOVEM B,HSTNUM		; save host number
	MOVX A,.LNSSY		; get root dir name of special hosts
	HRROI B,[ASCIZ/MAILS/]	; it is called MAILS:
	HRROI C,DIRSTR		; into DIRSTR
	LNMST%
	 ERJMP R		; no such name, no specials!
	MOVX A,RC%EMO		; require exact match
	HRROI B,DIRSTR		; of directory name
	RCDIR%			; see if such a directory exists
	 ERJMP R		; bogus name, barf
	JXN A,RC%NOM,R		; if no match, no special hosts
	MOVEM C,TOPDIR		; save directory number
	HRROI A,DIRSTR		; get canonical name string for MAILS:
	MOVE B,TOPDIR
	DIRST%
	 ERJMP R		; failed
	HRROI A,DIRSTR		; get name string for directory number
	MOVE B,HSTNUM		; get back desired address
	CAME B,[-1]		; want local address?
	IFSKP.
	  MOVE B,TOPDIR		; yes, get our address
	  MOVEM B,HSTNUM	; save for value return
	ENDIF.
	DIRST%			; get the name strig
	 ERJMP R		; failed
	LDB D,A			; get terminator for later
	SETZ B,			; flush terminating brocket
	DPB B,A
	DO.
	  SETO B,		; back up pointer one byte
	  ADJBP B,A
	  MOVE A,B		; update pointer to "host name"
	  LDB C,B		; see if found terminator
	  CAIE C,"["
	   CAIN C,"<"		; if at beginning then top level
	  IFSKP.
	    CAIE C,"."		; else try to find the dot
	     LOOP.		; didn't find it
	  ENDIF.
	ENDDO.
	MOVEM B,NAMPTR		; save name pointer
	MOVE A,HSTNUM		; see if local host
	CAMN A,TOPDIR		; if not we must make sure it's a subdir
	IFSKP.
	  DPB D,B		; stuff terminator
	  ILDB D,B		; get first byte of name
	  SETZ C,		; wipe it for test
	  DPB C,B
	  MOVX A,RC%EMO		; require exact match
	  HRROI B,DIRSTR	; of directory name
	  RCDIR%		; parse the name
	   ERJMP R		; bogus name, barf
	  JXN A,RC%NOM,R	; if no match, barf
	  CAME C,TOPDIR		; is superior the MAILS: directory?
	   RET			; no, lose
	  MOVE B,NAMPTR		; put first byte back again
	  IDPB D,B
	ENDIF.
	MOVE A,HSTPTR		; copy string
	MOVE B,NAMPTR
	SETZ C,			; no limit
	SOUT%
	 ERJMP R		; percolate failure up to caller
	HRROI B,[ASCIZ/#Special/] ; add Special domain
	CALL $ADDOM
	MOVE B,HSTNUM		; return host number too in case argument -1
	RETSKP

; $SPCSN - Translate "Special" host name to host address
; Accepts:
;	A/ pointer to host string
;	CALL $SPCSN
; Returns +1: Failed
;	  +2: Success, updated pointer in A, host address in B

$SPCSN::SAVEAC <C,D>
	STKVAR <HSTPTR,<HSTSTR,HSTNMW>,<DIRSTR,20>,TOPDIR,NAMPTR>
	MOVE B,A		; copy string so we can muck with it
	HRROI A,HSTSTR		; into HSTSTR
	MOVX C,HSTNML+1		; up to this many characters
	SETZ D,			; terminate on null
	SOUT%
	 ERJMP R		; percolate failure up to caller
	JUMPE C,R		; string too long if exhausted
	MOVEM B,HSTPTR		; save pointer
	SETO B,			; back pointer up by one
	ADJBP B,HSTPTR
	MOVEM B,HSTPTR		; save updated pointer
	HRROI A,HSTSTR		; now remove Special domain
	HRROI B,[ASCIZ/#Special/]
	CALL $RMDOM
	MOVX A,.LNSSY		; get root dir name of special hosts
	HRROI B,[ASCIZ/MAILS/]	; it is called MAILS:
	HRROI C,DIRSTR		; into DIRSTR
	LNMST%
	 ERJMP R		; no such name, no specials!
	MOVX A,RC%EMO		; require exact match
	HRROI B,DIRSTR		; of directory name
	RCDIR%			; see if such a directory exists
	 ERJMP R		; bogus name, barf
	JXN A,RC%NOM,R		; if no match, no special hosts
	MOVEM C,TOPDIR		; save directory number
	HRROI A,DIRSTR		; get canonical name string for MAILS:
	MOVE B,TOPDIR
	DIRST%
	 ERJMP R		; failed
	MOVEM A,NAMPTR		; save pointer for later
	LDB D,NAMPTR		; get terminator for later
	SETZ B,			; flush terminating brocket
	DPB B,NAMPTR
	DO.
	  SETO B,		; back up pointer one byte
	  ADJBP B,A
	  MOVE A,B		; update pointer to "host name"
	  LDB C,B		; see if found terminator
	  CAIE C,"["
	   CAIN C,"<"		; if at beginning then top level
	  IFSKP.
	    CAIE C,"."		; else try to find the dot
	     LOOP.		; didn't find it
	  ENDIF.
	ENDDO.
	HRROI B,HSTSTR		; see if it matches top directory
	STCMP%
	 ERJMP R
	IFE. A
	  MOVE B,TOPDIR		; matched, give top directory number
	ELSE.
	  MOVX B,"."		; it didn't, patch in subdir delimeter
	  DPB B,NAMPTR
	  MOVE A,NAMPTR
	  HRROI B,HSTSTR	; now patch in host name
	  SETZ C,
	  SOUT%
	  IDPB D,A		; add on directory delimiter
	  IDPB C,A		; and tie off with null
	  MOVX A,RC%EMO		; require exact match
	  HRROI B,DIRSTR	; of directory name
	  RCDIR%		; see if such a directory exists
	   ERJMP R		; bogus name, barf
	  JXN A,RC%NOM,R	; if no match, no such special host
	  MOVE B,C		; directory number of the "host"
	ENDIF.
	MOVE A,HSTPTR		; return updated pointer
	RETSKP

; $ADDOM - Add top-level domain name
; Accepts:
;	A/ pointer to host string
;	B/ pointer to domain name string
;	CALL $ADDOM
; Returns +1: Always, updated pointer in A

$ADDOM::SAVEAC <B,C>
	MOVEI C,"."		; add domain delimiter
	IDPB C,A
	SETZ C,			; no limit
	SOUT%
	RET

; $RMDOM - Remove top-level domain name
; Accepts:
;	A/ pointer to host string
;	B/ pointer to domain name string
;	CALL $RMDOM
; Returns +1: Always

$RMDOM::SAVEAC <B>
	STKVAR <HSTPTR,DOMPTR,DOMNAM>
	SETZM DOMPTR		; initially no top-level domain pointer
	MOVEM B,DOMNAM
	TXC A,.LHALF		; is source LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; set up pointer to return
	DO.
	  ILDB B,A		; get a byte from name
	  IFN. B		; if null, scan done
	    CAIN B,"."		; start of a domain segment?
	     MOVEM A,DOMPTR	; yes, remember its pointer
	    LOOP.
	  ENDIF.
	ENDDO.
	SKIPN B,DOMPTR		; get pointer to top-level domain
	IFSKP.
	  MOVE A,DOMNAM		; see if top-level domain is the one we want
	  STCMP%
	  IFE. A		; name match?
	    SETZ A,		; yes, tie off string before top-level domain
	    DPB A,DOMPTR
	  ENDIF.
	ENDIF.
	MOVE A,HSTPTR
	RET

; $RMREL - Remove top-level relative domain names
; Accepts:
;	A/ pointer to host string
;	CALL $RMREL
; Returns +1: Always

$RMREL::SAVEAC <B>
	STKVAR <HSTPTR,DOMPTR>
	TXC A,.LHALF		; is source LH -1?
	TXCN A,.LHALF
	 HRLI A,(<POINT 7,>)	; yes, set up byte pointer
	MOVEM A,HSTPTR		; set up pointer to return
	DO.
	  SETZM DOMPTR		; initially no top-level domain pointer
	  DO.
	    ILDB B,A		; get a byte from name
	    IFN. B		; if null, scan done
	      CAIN B,"."	; start of a domain segment?
	       MOVEM A,DOMPTR	; yes, remember its pointer
	      LOOP.
	    ENDIF.
	  ENDDO.
	  MOVE A,HSTPTR		; get host pointer for return or loopback
	  SKIPN B,DOMPTR	; get pointer to top-level domain
	  IFSKP.
	    ILDB B,B		; get first byte of domain name
	    CAIE B,"#"		; relative domain?
	    IFSKP.
	      SETZ B,		; yes, tie off string before top-level domain
	      DPB B,DOMPTR
	      LOOP.		; re-do to eliminate other relative domains
	    ENDIF.
	  ENDIF.
	ENDDO.
	RET

	END