source: FOIAVistA/tag/r/HEALTH_LEVEL_SEVEN-HL/HLOTCP.m@ 628

HLOTCP ;ALB/CJM- TCP/IP I/O - 10/4/94 1pm ;07/10/2007
 ;;1.6;HEALTH LEVEL SEVEN;**126,131,134,137**;Oct 13, 1995;Build 21
 ;Per VHA Directive 2004-038, this routine should not be modified.
 ;
OPEN(HLCSTATE,LOGICAL) ;
 ;This may be called either in the context of a client or a server.
 ;For the server, there are 3 situations:
 ; 1) The server is not concurrent.  In this case the TCP device should be opened.
 ; 2) The server is concurrent, but this process was spawned by the OS
 ;    (via a VMS TCP Service)  In this case, the device should be opened
 ;    via the LOGICAL that was passed in.
 ;  3) The server is concurrent, but this process was spawned by the
 ;     TaskMan multi-listener.  In this case TaskMan already opened the
 ;     device.  This case can be determined by the absence of the LOGICAL
 ;     input parameter.
 ;
 N IP,PORT,DNSFLAG
 ;
 S DNSFLAG=0 ;DNS has not been contacted for IP
 ;
 S:'$G(HLCSTATE("SERVER")) IP=HLCSTATE("LINK","IP")
 S PORT=HLCSTATE("LINK","PORT")
 S HLCSTATE("CONNECTED")=0
 S HLCSTATE("READ HEADER")="READHDR^HLOTCP"
 S HLCSTATE("WRITE HEADER")="WRITEHDR^HLOTCP"
 S HLCSTATE("READ SEGMENT")="READSEG^HLOTCP"
 S HLCSTATE("WRITE SEGMENT")="WRITESEG^HLOTCP"
 S HLCSTATE("END MESSAGE")="ENDMSG^HLOTCP"
 S HLCSTATE("CLOSE")="CLOSE^HLOTCP"
 ;
 ;spawned by TaskMan multi-listener? If so, the device has already been opened
 I $G(HLCSTATE("SERVER")),$G(HLCSTATE("LINK","SERVER"))="1^M",$G(LOGICAL)="" D  Q
 .S HLCSTATE("DEVICE")=IO(0),HLCSTATE("FLUSH")="!",HLCSTATE("TCP BUFFER SIZE")=510
 .S HLCSTATE("CONNECTED")=1
 ;
 ;if no IP, not a server, give DNS a shot
 I '$G(HLCSTATE("SERVER")),IP="" S DNSFLAG=1,IP=$$DNS(HLCSTATE("LINK","DOMAIN")),HLCSTATE("LINK","IP")=IP Q:IP=""
 ;
RETRY I HLCSTATE("SYSTEM","OS")="DSM" D
 .S HLCSTATE("TCP BUFFER SIZE")=512
 .I $G(LOGICAL)]"" S HLCSTATE("DEVICE")=LOGICAL
 .E  S HLCSTATE("DEVICE")=PORT
 .S HLCSTATE("FLUSH")="!"
 .I $G(HLCSTATE("SERVER")) D
 ..O:$G(LOGICAL)]"" HLCSTATE("DEVICE"):(TCPDEV,BLOCKSIZE=512):HLCSTATE("OPEN TIMEOUT")
 ..O:$G(LOGICAL)="" HLCSTATE("DEVICE"):(TCPCHAN,BLOCKSIZE=512):HLCSTATE("OPEN TIMEOUT")
 ..I $T D
 ...S HLCSTATE("CONNECTED")=1
 ...U HLCSTATE("DEVICE"):NOECHO
 .E  D  ;client
 ..O HLCSTATE("DEVICE"):(TCPCHAN,ADDRESS=IP,BLOCKSIZE=512):HLCSTATE("OPEN TIMEOUT")
 ..I $T D
 ...S HLCSTATE("CONNECTED")=1
 ...U HLCSTATE("DEVICE"):NOECHO
 E  I HLCSTATE("SYSTEM","OS")="CACHE" D
 .S HLCSTATE("FLUSH")="!"
 .I $G(LOGICAL)]"" S HLCSTATE("DEVICE")=LOGICAL
 .E  S HLCSTATE("DEVICE")="|TCP|"_PORT
 .S HLCSTATE("TCP BUFFER SIZE")=510
 .I $G(HLCSTATE("SERVER")) D
 ..I HLCSTATE("SERVER")="1^S" D  Q
 ...;single server (no concurrent connections)
 ...O HLCSTATE("DEVICE"):(:PORT:"+A-S":::):HLCSTATE("OPEN TIMEOUT")
 ...I $T D
 ....N A
 ....S HLCSTATE("CONNECTED")=1
 ....U HLCSTATE("DEVICE")
 ....F  R *A:HLCSTATE("READ TIMEOUT") Q:$T  I $$CHKSTOP^HLOPROC S HLCSTATE("CONNECTED")=0 D CLOSE(.HLCSTATE) Q
 ..;
 ..;multi-server spawned by OS - VMS TCP Services
 ..O HLCSTATE("DEVICE")::HLCSTATE("OPEN TIMEOUT") I '$T S HLCSTATE("CONNECTED")=0 Q
 ..S HLCSTATE("CONNECTED")=1
 ..U HLCSTATE("DEVICE"):(::"-S")
 ..;
 .E  D  ;client
 ..S HLCSTATE("TCP BUFFER SIZE")=510
 ..O HLCSTATE("DEVICE"):(IP:PORT:"-S":::):HLCSTATE("OPEN TIMEOUT")
 ..I $T D
 ...S HLCSTATE("CONNECTED")=1
 E  D  ;any other system but Cache or DSM
 .S HLCSTATE("TCP BUFFER SIZE")=256
 .D CALL^%ZISTCP(IP,PORT,HLCSTATE("OPEN TIMEOUT"))
 .S HLCSTATE("CONNECTED")='POP
 .I HLCSTATE("CONNECTED") S HLCSTATE("DEVICE")=IO
 ;
 ;if not connected, not the server, give DNS a shot if not tried already
 I '$G(HLCSTATE("SERVER")),'HLCSTATE("CONNECTED"),'DNSFLAG S DNSFLAG=1,IP=$$DNS(HLCSTATE("LINK","DOMAIN")) I IP]"",IP'=HLCSTATE("LINK","IP") S HLCSTATE("LINK","IP")=IP G RETRY
 I HLCSTATE("CONNECTED"),DNSFLAG S $P(^HLCS(870,HLCSTATE("LINK","IEN"),400),"^")=IP
 Q
 ;
DNS(DOMAIN) ;
 Q $P($$ADDRESS^XLFNSLK(DOMAIN),",")
 ;
WRITEHDR(HLCSTATE,HDR) ;
 ;
 ;insure that package buffer is empty
 K HLCSTATE("BUFFER")
 S HLCSTATE("BUFFER","BYTE COUNT")=0
 S HLCSTATE("BUFFER","SEGMENT COUNT")=0
 S HLCSTATE("FIRST WRITE")=1 ;so that FLUSH knows $X should be 0
 ;
 ;Start the message with <SB>, then write the header
 N SEG
 S SEG(1)=$C(11)_HDR(1)
 S SEG(2)=HDR(2)
 Q $$WRITESEG(.HLCSTATE,.SEG)
 ;
WRITESEG(HLCSTATE,SEG) ;
 N I,LAST
 S HLCSTATE("BUFFER","SEGMENT COUNT")=HLCSTATE("BUFFER","SEGMENT COUNT")+1
 S I=0,LAST=$O(SEG(99999),-1)
 F  S I=$O(SEG(I)) Q:'I  D
 .I HLCSTATE("BUFFER","BYTE COUNT")>HLCSTATE("SYSTEM","BUFFER") D FLUSH
 .I I=LAST S SEG(I)=SEG(I)_$C(13)
 .S HLCSTATE("BUFFER",HLCSTATE("BUFFER","SEGMENT COUNT"),I)=SEG(I),HLCSTATE("BUFFER","BYTE COUNT")=HLCSTATE("BUFFER","BYTE COUNT")+$L(SEG(I))+20
 Q HLCSTATE("CONNECTED")
 ;
FLUSH ;flushes the HL7 package buffer, and the system TCP buffer when full
 N SEGMENT,MAX
 S SEGMENT=0
 S MAX=HLCSTATE("TCP BUFFER SIZE")
 U HLCSTATE("DEVICE") I (HLCSTATE("SYSTEM","OS")="CACHE") S HLCSTATE("CONNECTED")=($ZA\8192#2) I 'HLCSTATE("CONNECTED") D CLOSE(.HLCSTATE)
 F  S SEGMENT=$O(HLCSTATE("BUFFER",SEGMENT)) Q:'SEGMENT  D
 .N I S I=0
 .F  S I=$O(HLCSTATE("BUFFER",SEGMENT,I)) Q:'I  D
 ..N LINE,J
 ..S J=$S(HLCSTATE("FIRST WRITE"):0,1:$X)
 ..S HLCSTATE("FIRST WRITE")=0
 ..S LINE=HLCSTATE("BUFFER",SEGMENT,I)
 ..F  Q:'(J+$L(LINE)>MAX)  D
 ...W $E(LINE,1,MAX-J),@HLCSTATE("FLUSH") S HLCSTATE("FLUSHED")=1
 ...S LINE=$E(LINE,(MAX-J)+1,99999)
 ...S J=0
 ..I (LINE]"") W LINE S HLCSTATE("FLUSHED")=0
 K HLCSTATE("BUFFER")
 S HLCSTATE("BUFFER","SEGMENT COUNT")=1
 S HLCSTATE("BUFFER","BYTE COUNT")=0
 S HLCSTATE("FIRST WRITE")=0
 Q
 ;
READSEG(HLCSTATE,SEG) ;
 ;
 ;Output:
 ;  SEG - returns the segment (pass by reference)
 ;  Function returns 1 on success, 0 on failure
 ;
 N SUCCESS,COUNT,BUF
 S (COUNT,SUCCESS)=0
 K SEG
 ;
 ;anything left from last read?
 S BUF=HLCSTATE("READ")
 S HLCSTATE("READ")=""
 I BUF]"" D  ;something was left!
 .S COUNT=1
 .I BUF[$C(13) D  Q
 ..S SEG(1)=$P(BUF,$C(13)),BUF=$P(BUF,$C(13),2,9999)
 ..S SUCCESS=1
 .S SEG(1)=BUF,BUF=""
 I 'SUCCESS U HLCSTATE("DEVICE") F  R BUF:HLCSTATE("READ TIMEOUT") Q:'$T  D  Q:SUCCESS
 .I BUF[$C(13) S SUCCESS=1,COUNT=COUNT+1,SEG(COUNT)=$P(BUF,$C(13)),BUF=$P(BUF,$C(13),2,9999) Q
 .S COUNT=COUNT+1,SEG(COUNT)=BUF
 ;
 I SUCCESS D
 .S HLCSTATE("READ")=BUF ;save the leftover
 .I COUNT>1,SEG(COUNT)="" K SEG(COUNT) S COUNT=COUNT-1
 ;Cache can return the connection status
 E  I (HLCSTATE("SYSTEM","OS")="CACHE") S HLCSTATE("CONNECTED")=($ZA\8192#2) I 'HLCSTATE("CONNECTED") D CLOSE(.HLCSTATE)
 ;
 ;if the <EB> character was encountered, then there are no more segments in the message, set the end of message flag
 I SUCCESS,SEG(COUNT)[$C(28) D
 .K SEG
 .S SUCCESS=0
 .S HLCSTATE("MESSAGE ENDED")=1
 Q SUCCESS
 ;
READHDR(HLCSTATE,HDR) ;
 ;reads the next header segment in the message stream, discarding everything that comes before it
 ;
 N SEG,SUCCESS,J,I
 S SUCCESS=0
 K HDR
 F  Q:'$$READSEG(.HLCSTATE,.SEG)  D  Q:SUCCESS
 .S I=0
 .;look for the <SB>
 .;perhaps the <SB> isn't in the first line
 .F  S I=$O(SEG(I)) Q:'I  D  Q:SUCCESS
 ..I (SEG(I)'[$C(11)) K SEG(I) Q
 ..S SEG(I)=$P(SEG(I),$C(11),2)
 ..S SUCCESS=1
 ..K:SEG(I)="" SEG(I)
 I SUCCESS S (I,J)=0 F  S J=$O(SEG(J)) Q:'J  S I=I+1,HDR(I)=SEG(J)
 Q SUCCESS
 ;
CLOSE(HLCSTATE) ;
 CLOSE HLCSTATE("DEVICE")
 Q
 ;
ENDMSG(HLCSTATE)        ;
 N SEG
 S SEG(1)=$C(28)
 I $$WRITESEG(.HLCSTATE,.SEG) D  Q 1
 .D FLUSH
 .U HLCSTATE("DEVICE")
 .I ('$G(HLCSTATE("FLUSHED")))!$X W @HLCSTATE("FLUSH") S HLCSTATE("FLUSHED")=1
 Q 0