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