Type ASSEMBLE
Source Lines : 459
Fixes Applied : 4
Most Recent Version : Tuesday, December 12, 1978
Last Fix ID : [HRC105DS]

Module

       DMSSTT

Function

       TO LOCATE  THE FILE  STATUS TABLE  ENTRY FOR  A GIVEN
       FILE, AND IF FOUND TO PROVIDE  THE CALLER WITH A COPY
       THEREOF.

Attributes

       NUCLEUS RESIDENT, REENTRANT

Operation

       DMSSTT CHECKS THE FILE NAME AND FILE TYPE
       FOR ILLEGAL CHARACTERS AND RETURNS IF ONE IS
       FOUND. THEN CHECK FOR VALID MODE SPECIFICATION
       IF INVALID RETURN. IF A MODE LETTER WAS GIVEN
       CALL DMSLAD TO FIND ADT. RETURN IF DISK IS NOT
       ACCESSED.

       DMSSTTE CALLS DMSLAF  TO SEE IF THE GIVEN  FILE IS IN
       THE ACTIVE FILE TABLE.
       IF FOUND, THE ACTIVE 40-BYTE  FST ENTRY IS MOVED FROM
       AFTFST IN THE AFT BLOCK TO THE COPY AT STATEFST TO BE
       PROVIDED TO THE  CALLER, AND THE STATER0  AND STATER1
       WORDS FOLLOWING STATEFST ARE SET  TO THE ADDRESSES OF
       THE ADT  BLOCK AND THE  FST ENTRY  RESPECTIVELY; THEN
       V(STATEFST)  IS STORED  IN  THE  CALLER'S P-LIST  (IF
       NECESSARY) AS DESCRIBED BELOW.

       IF THE  FILE WAS  NOT FOUND  BY DMSLAF,  DMSSTTE THEN
       CALLS DMSLFS TO FIND THE GIVEN  FILE. IF NOT FOUND BY
       DMSLFS, THE ERROR CODE FROM DMSLFS (28 FOR FILE NOT
       FOUND) IS RETURNED TO THE CALLER AS SHOWN IN THE EXIT
       CONDITIONS.

       IF THE  FILE WAS  FOUND BY  DMSLFS, THEN  THE 40-BYTE
       ENTRY IS MOVED TO STATEFST, AND
       THE R0 AND R1 VALUES  OBTAINED FROM DMSLFS ARE STORED
       AT THE STATER0 AND STATER1
       WORDS FOLLOWING  STATEFST.  (THESE WORDS ARE  USED BY
       RDBUF TO AVOID AN EXTRA
       SEARCH  OF THE  FST  TABLES  UNDER THE  CIRCUMSTANCES
       GIVEN IN THE DMSBRD DESCRIPTION).
       WHERE THE FILE  WAS FOUND BY FSTLKP,  THE MODE LETTER
       IS STORED IN THE STATEFST COPY
       USING THE SAME ALGORITHM AS DMSLAFFE, BEING CAREFULLY
       CHOSEN FROM THAT OF THE CALLER'S
       PARAMETER LIST,  OR THE ADTM  OR ADTMX MODE  GIVEN BY
       THE ACTIVE DISK TABLE.

       THE RESULT  OF THE CHOICE OF  MODE-LETTER FACILITATES
       THE FEATURE OF A READ-ONLY EXTENSION OF A GIVEN DISK.
       FOR EXAMPLE, IF A B-DISK  IS A READ-ONLY EXTENSION OF
       A A-DISK,  IF THE  CALLER'S PARAMETER  LIST SPECIFIED
       THE B-MODE,  THE MODE STORED  IN STATEFST WILL  BE B;
       BUT IF THE CALLER SPECIFIED A OR '*', THE MODE STORED
       IN STATEFST WILL BE A.

       AFTER  SETTING UP  STATEFST AND  THE  TWO WORDS  THAT
       FOLLOW,  AS DESCRIBED  DMSSTT STORES  THE ADDRESS  OF
       STATEFST IN THE CALLER'S P-LIST (UNLESS IT IS ALREADY
       THERE), AND  RETURNS TO  THE CALLER  AS SHOWN  IN THE
       EXIT CONDITIONS.

       Also fill in various members in an extended STATEFST. HRC105DS
       This is done for compatibility with later software    HRC105DS
       which targets VM/SP, however, it is not possible to   HRC105DS
       use the greater capacity of some of these counters    HRC105DS
       with 800 byte disk blocks which are limited to 40     HRC105DS
       byte FSTs and cannot accomodate the larger values.    HRC105DS

Calls to Other Routines

       DMSLAF,DMSLFS,DMSLAD,DMSERR