top - download
⟦3e0572107⟧ Wang Wps File
Length: 6545 (0x1991)
Types: Wang Wps File
Notes: Spelunked
Names: »~ORPHAN61.00«
Derivation
└─⟦fa4d101ea⟧ Bits:30005807 8" Wang WCS floppy, CR 0112A
└─ ⟦this⟧ »~ORPHAN61.00«
WangText
…00……00……00……00……00…=…02……00……00…=
= =…07…<…08…<…09…<…0f…<…05…;…0c…;…0d…;…02…;
; ;…05…;…06…;…07…:…0c…:…0d…:…0e…:…0f…:…02…:
:…05…:…06…:…07…9…08…9…0e…9…0f…9
9 9…07…8…08…8…0f…8…00…8
8…07…7…0b…7…0f…7
7…06…6…09…6…0d…6…01……86…1 …02… …02… …02…
…02…CPS/SDS/039
…02…820104…02……02…
USER VDU
DETAILED DESIGN SPECIFICATION…02……02…CAMPS
Fig. 4.1.1.4-2
4.1.2 S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲p̲e̲c̲i̲f̲i̲c̲a̲t̲i̲o̲n̲
In this section the software structure of VUP will
be described. The allocation of functions onto processes
and coroutines will be explained, based o the analysis
performed in section 4.1.1.
Figure 4.1.2-1 shows the mapping of functions onto
processes and coroutines
4.1.2.1. V̲U̲S̲ ̲P̲r̲o̲c̲e̲s̲s̲
The VDU USER PROCESS controls the interaction with
the user VDU, under supervision of TEMCO (SSC softwre).
It thus has the following responsibilities:
- TEMCO command execution
- Control and execution of user transactions
- User transaction accounting
- Maintaining the VDU Header queue status
- Monitoring of FLASH queues.
Fig. 4.1.2-1
Fig. 4.1.2.1-1 VUS Structure
4.1.2.1.1 V̲U̲S̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲s̲
The VDU USER PROCESS consists of four coroutines:
- the VDU Control Coroutine
- the User Function Control Coroutine
- the VDU Dialogue Coroutine
- he Retrieve Coroutine.
In figure 4.1.2.1-1 an overview of VUS is depicted.
4.1.2.1.1.1 V̲D̲U̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲
The VDU Control (VCO) Coroutine is the controlling
coroutine, controlling the start / stop of the processing
of all the other corouines.
VCO is responsible for the execution of commands received
from TEMCO, e.g initialize, close down, restart, start/stop,
for VDU Header queue status update and that no message
is kept longer in a Flash precedence queue than allowed
by the suprvisor.
During the analysis it was found that TEMCO Control
Functions and Queue Status Maintenance functions were
to be executed with higher priority than User Transaction
Control Functions. Thus these two functions have been
allocated their own oroutine named V̲DU C̲O̲NTROL COROUTINE
(VCO).
The VCO coroutine shall be asssigned the highest priority
among the coroutines of VUS, meaning that whenever
VCO and other VUS coroutines are ready to run, VCO
shall be allowed to run first.
4.1.2.1..2 U̲s̲e̲r̲ ̲F̲u̲n̲c̲t̲i̲o̲n̲ ̲C̲o̲n̲t̲r̲o̲l̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲
The User Function Control (UFCO) Coroutine performs
the direct control of the VDU Dialogue Coroutine.…86…1
…02… …02… …02… …02…
UFCO performs the user transaction control, which consists
of:
- user transaction execution
- user requested transaction interruption
- user transaction accounting.
The fnctions of UFCO and VDIA have been assigned separate
coroutines to decrease the complexity of the software.
When a user transaction is in progress, UFCO software
shall only take care of transaction interruption while
all formatting and I/O transferinitiation / awaiting
is performed by VDIA. UFCO is assigned a higher priority
than VDIA.
4.1.2.1.1.3 V̲D̲U̲ ̲D̲i̲a̲l̲o̲g̲u̲e̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲s̲
The VDU dialogue (VDIA) coroutine is responsible for
the VDU format transfromation of input and output and
for validaion of user input.
4.1.2.1.1.4 R̲e̲t̲r̲i̲e̲v̲e̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲
The Retrieve (RETR) Coroutine is responsible for reception
and treatment of retrieval answers from SAR.
The functions of RETR have been assigned to a separate
coroutine, due to the fact thatthe function may be
performed even when the other coroutines have been
stopped after user sign-off. Furthermore, the function
of the RETR may be considered as low priority tasks,
having in mind that during on-line retrieval all the
other coroutinesassociated with user transaction processing
(UFCO, VDIA) will await input from RETR, thereby allowing
RETR to be processing. RETR is assigned the lowest
priority within VUS.
4.1.2.2 U̲M̲A̲M̲ ̲P̲r̲o̲c̲e̲s̲s̲
The UMAM process controls the access to the preparation
database and maintains the Outgoing Message Status,
the Release Status, the Delivery Status and the Srvice
Message Status for each VDU and printer.
In figure 4.1.2.1-2 an overview of the UMAM process
is shown.
The functions of UMAM have been allocated their own
process for the following reasons:
a) To keep security access control as simple ad tight
as possible.
b) To minimize the damage caused by system malfunction.
With reference to the analysis in 4.1.1.4.1 this
means that the solution where the releaser process
queues a request for removing or changing items
is not chosen. Note tat due to security, it is
our aim that a user process should not be trusted,
meaning that access rights possessed by an unassigned
user process (no user has signed on) shall be kept
at a minimum.
c) The close relationship between Preparation Dataase
Access Control and Message / Comment Status Maintenance
has caused both functions to be allocated to the
same process.
d) The allocation of one process to Status Maintenance
gives the disigner the freedom to optimize disk-accesses
and to utilze the fact that identical entries in
different status types exist.
e) The centralization of status maintenance and PDB
access control for all VDU processes in one process,
increases the flexibility of the system.
4.1.2.3 S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲t̲r̲u̲c̲t̲u̲r̲e̲
n the preceding subsections of section 4.1.2, the processes
and coroutines of VUP have been isolated, and the functions
to be performed by these software components identified.
F̲I̲G̲U̲R̲E̲ ̲4̲.̲1̲.̲2̲.̲1̲-̲…86…1 …02… …02… …02… …02…
The software structure for each component (i.e. coroutine)
will be outlined in the following subsections. The
description of the software structure will mainly be
in the form of sftware structure charts and references
should be made to the functional specification given
in section 4.1.1. The denotation used in section 4.1.1
has as far as possible been used in the software structure
charts, with the purpose of highlighting te close relationship.
Thus the identification of programme tasks is given
in narrative English and not as programme or procedure
names.
4.1.2.3.1 V̲C̲O̲ ̲C̲o̲r̲o̲u̲t̲i̲n̲e̲ ̲S̲o̲f̲t̲w̲a̲r̲e̲ ̲S̲t̲r̲u̲c̲t̲u̲r̲e̲
The software structure of the VDU Control Coroutine
(VCO) is out
