Type ASSEMBLE
Source Lines : 1,744
Fixes Applied : 22
Most Recent Version : Tuesday, December 12, 1978
Last Fix ID : [R14488DS]
Module
DMSSOP (SOOPCL)
Function
TO PROCESS OS OPEN AND CLOSE MACROS.
Attributes
REENTRANT, NUCLEUS RESIDENT.
Operation
INITIALIZATION
IOTYPE IS SET TO INDICATE OPEN OR OPENJ, UPON ENTRY TO
SOOPCL, AND THE ADDRESS OF THE CURRENT DCB IS OBTAINED
FROM THE LIST POINTED TO BY REGISTER 1.
VSAM
IF ANY OR ALL OF THE CONTROL BLOCKS POINTED TO BY
THE ADDRESSES IN THE PLIST ARE ACB'S, A BALR IS
MADE TO THE OS VSAM INTERFACE AFTER COMPLETION OF
DCB PROCESSING. THE ADDRESS OF THE INTERFACE IS
OBTAINED FROM CVT+256( PRIOR TO THE FIRST CALL,
THIS CELL CONTAINS THE ADDRESS OF THE INTERFACE
BOOTSTRAP).
A PARAMETER LIST IS CONSTRUCTED IN THE USER SAVE
AREA AS FOLLOWS:
DC CL1'O' OPTION BYTE (C'O'-OPEN,
C'C'-CLOSE, C'T'-TCLOSE)
DC CL3'SOP' SOP IDENTIFIER
UPON RETURN FROM DMSVIP, REGISTER 15 CONTAINS THE
RETURN CODE FROM THE DOS VSAM OPEN ROUTINE.
DETERMINATION OF ACCESS METHOD
THE DATA SET ORGANIZATION (DCBDSORG) SWITCH IS
CHECKED TO BE SURE IT IS EITHER PHYSICAL
SEQUENTIAL, PARTITIONED, OR DIRECT ACCESS
(EFFECTIVELY ELIMINATING ONLY ISAM). IF NONE OF
THE ABOVE, THE DCB WILL NOT BE OPENED.
NEXT THE MACRO FORMAT FIELD (DCBMACRF) IS CHECKED
TO SEE WHICH ACCESS METHOD IS REQUESTED, AND THE
ACCESS METHOD INDICATOR (DCBCIND2) IS SET TO
SIGNAL QSAM OR BSAM.
QSAM
IF THE ACCESS METHOD IS QSAM, DCBMACRF IS TESTED
FOR A GET, UPDATE OR PUT REQUEST, AND THE RELEVANT ROUTINE
ADDRESS IS PLACED IN THE CORRESPONDING DCB ACCESS
FIELD (NOTE THAT GET, UPDATE AND PUT ARE IN THE CMS
ROUTINE DMSSQS)
BSAM
IF THE ACCESS METHOD IS BSAM, THE ADDRESS OF
DMSSBS IS PLACED IN DCB ACCESS FIELD; THE CHECK
ADDRESS IS PLACED IN THE DCB CHECK FIELD; AND IF
POINT IS REQUESTED, THE DMSSCT ADDRESS IS PLACED
IN THE DCBNOTE FIELD.
SETTING UP DCB FIELDS
AFTER THE RELEVANT QSAM OR BSAM PROCESSING,
THE CMSCB(FCB) CHAIN IS TESTED TO
SEE IF THERE IS A CMSCB FOR THIS DCB. THAT IS, IF
A FILEDEF COMMAND FOR THE RESPECTIVE DATA SET HAS
BEEN ISSUED. IF ONE DOES NOT EXIST, THE ASSUMPTION
IS MADE THAT THE USER HAS SET UP THE REQUIRED DCB
FIELDS, AND FILEDEF IS CALLED TO CREATE A CMSCB
WITH A FILENAME OBTAINABLE FROM LOCATION CMSNAME
(INITIALIZED AS 'FILE'),
A FILEMODE OF A1, AND A FILETYPE EQUAL TO THE DCB
DDNAME. AFTER A MATCHING CMSCB IS FOUND OR CREATED,
IT IS USED TO FILL IN VACANT ENTRIES IN THE
DCB. IF THE MACLIB CONCAT OPTION IS ON IN THE CMSCB,
OPEN CHECKS THE MACLIB NAMES IN THE GLOBAL LIST AND
FILLS IN THE ADDRESSES OF OS FSTS FOR ANY MACLIBS THAT
ARE ON OS DISKS. THE CMSCB OF THE 1ST MACLIB IN THE
GLOBAL LIST IS USED FOR CMSCB MERGING AND INITIAL-
IZATION.
THE FOLLOWING TABLE SHOWS THE CMSCB FIELDS THAT
ARE USED TO COMPLETE DCB FILEDS NOT INITIALIZED BY
THE USER PRIOR TO ISSUING THE OPEN CALL. IT ALSO
SHOWS THE JFCBMASK BIT SETTING WHICH IS ON IF THE
ASSOCIATED CMSCB FIELD MUST BE USED. IF THE CMSCB
FIELDS ARE NOT SPECIFIED BY A FILEDEF
COMMAND, NO DEFAULTS WILL BE USED TO FILL IN THE
RESPECTIVE FIELDS OF THE CMSCB.
_______________________________________
| DCB || FCB | JFCBMASK |
|___________||____________|___________|
|-----------||------------|-----------|
| || | |
| DCBBLKSI || JFCBLKSI |+2 X'10' |
| DCBDSORG || JFCDSORG |+3 X'01' |
| DCBLRECL || JFCLRECL |+3 X'02' |
| DCBRECFM || JFCRECFM |+2 X'04' |
| DCBKEYLE || JFCKEYLE |+3 X'20' |
| DCBOPTCD || JFCOPTCD |+2 X'80' |
| DCBLIMCT || JFCLIMCT |+2 X'40' |
|___________||____________|___________|
SETTING UP A NEW CMSCB
THIS ROUTINE IS ENTERED IF IT IS NECESSARY TO SET
UP AND INITIALIZE A NEW CMSCB FOR THE DCB
CURRENTLY BEING OPENED. IT ISSUES A FILEDEF
WITH THE FOLLOWING FIELDS FILLED IN:
________________________________________________________
| FIELD || CONTENT | DESCRIPTION |
|____________||_____________|__________________________|
|------------||-------------|--------------------------|
| FCBSECT || X'08' | INDICATES OPEN ACQUIRED |
| || | THIS CMSCB. |
| FCBDEV || X'14' | DISK DEFAULT |
| FCBDSNAM || FILENAME | CMS FILENAME ('FILE') |
| FCBDD || DCBDDNAM | CMS FILETYPE |
| FCBDSTYP || DCBDDNAM | CMS FILETYPE |
| FCBDSMD || FILEMODE | CMS FILEMODE ('A1') |
|____________||_____________|__________________________|
SETTING UP CONTROL BLOCK POINTERS
AFTER THE CMSCB IS INITIALIZED, THE ADDRESS
POINTERS ARE SET TO LINK THE VARIOUS SIMULATED
CONTROL BLOCKS.
___________________________________________________________
| CONTROL | || |
| BLOCK | FIELD || CONTENTS AFTER COMPLETION |
|___________|___________||________________________________|
| | || |
| DCB | DCBDEBAD || DEB ADDRESS |
| DCB | DCBIOBAD || IOB ADDRESS |
| DCB | DCBIOBA || IOB ADDRESS |
| DCB | DCBIOBL || LENGTH IN DOUBLE WORDS OF IOB |
|___________|___________||________________________________|
| IOB | IOBDCBPT || DCB POINTER |
|___________|___________||________________________________|
| DEB | DEBDCBAD || DCB POINTER |
| DEB | DEBDEBID || X'0F' FLAG TO SHOW BLOCK IS DEB|
| DEB | DEBOPATB || OPEN OPTION BYTE |
|___________|___________||________________________________|
Calls to Other Routines
DMSFLD, DMSSTT, DMSERS, DMSERR, DMSCPF, DMSTIO, DMSFNS,
GETMAIN, OPEN EXIT ROUTINE, PDSSAVE AND KEYSAVE IN DMSSVT,
GETPOOL, FIND, DMSSCTCE, DMSVIB, DMSVIP.