;*; Updated on 06-Dec-91 at 9:16 AM by Michele Tonti; edit time: 0:00:12
;*************************** AMUS Program Label ******************************
; Filename: DSKFRE.M68 Date: 12/6/91
; Category: SBR Hash Code: 561-445-106-040 Version:
; Initials: KUNI/AM Name: RENE S. HOLLAN
; Company: UDISCO LTD. Telephone #: 5144818107
; Related Files: DSKFRE.SBR,DSKFRE.DOC,DSKFRE.BAS,DSKFRE.RUN,DSKFRE.LIT
; Min. Op. Sys.: Expertise Level:
; Special:
; Description: Returns the largest contiguous block free and the total number
; of blocks free on a specified device.
;
;*****************************************************************************
;************************************************************************
; *
; DSKFRE BASIC SUBROUTINE *
; *
;************************************************************************
;
; NOTICE
;
;All rights reserved. This software is the property of UDISCO LTD. and
;the material contained herein is the proprietary property and trade
;secrets of UDISCO LTD., embodying substantial creative efforts and
;confidential information, ideas and expressions, no part of which may be
;reproduced or transmitted in any form or by any means, electronic,
;mechanical, or otherwise, including photocopying or input into any
;information storage or retrieval system without the express written
;permission of UDISCO LTD.
;
;Permission to copy and use is granted to AMUS members for non commercial
;purposes only.
;
; Author: Rene S. Hollan
; Date Written: June 3, 1989
;
; COPYRIGHT (C) 1989 - UDISCO LTD.
;
;Edit History
;
;[100] 3 July 89
; Coding starts. /RSH
;
; Usage: XCALL DSKFRE,<device spec.>,<contig>,<total>
;
; Where <device spec.> is device specification (i.e. DSK0:),
;
; <contig> receives size of largest contigous block,
;
; <total> receives total number of blocks free.
;
; <contig> and <total> must be mapped as floating point
; variables, i.e.:
;
; MAP1 contig,F,6
; MAP1 total,F,6
;
; If an error occurs (bad device spec., etc.) contig is set to
; 0 and the file system error code is returned in total.
;
; Note that the device driver for the specified device must be loaded
; into memory and that there must be sufficient memory available in the
; BASIC impure area to hold a 24 byte result table (from DSKFRE), a DDB,
; and a 512 byte disk buffer.
;
SEARCH SYS
SEARCH SYSSYM
OBJNAM 0,0,[SBR]
VMAJOR = 1 ; major version
VMINOR = 0 ; minor version
VSUB = 0 ; sub version
VEDIT = 100. ; edit level
VWHO = 0 ; patch level
; On entry A3 points to the following parameter block
OFINI ; BASIC calling parameter area
OFDEF Bas.No,2 ; number of parameters (3)
OFDEF Bas.T1,2 ; type code (string)
OFDEF Bas.A1,4 ; variable address
OFDEF Bas.L1,4 ; variable length
OFDEF Bas.T2,2 ; type code (string)
OFDEF Bas.A2,4 ; variable address
OFDEF Bas.L2,4 ; variable length
OFDEF Bas.T3,2 ; type code (string)
OFDEF Bas.A3,4 ; variable address
OFDEF Bas.L3,4 ; variable length
OFSIZ Bas.Sz ; parameter area size
DSKFRE: PHDR -1,PV$RSM,PH$REU!PH$REE ; program header
MOV Bas.A1(A3),A2 ; A2 -> device name
MOV A4,A5 ; A5 -> device table
LEA A4,DF.SIZ(A4) ; adjust for device table size
ORB #D$BYP+D$ERC,D.FLG(A4) ; bypass error messages
FSPEC @A4 ; FSPEC the device name into imp. area
BNE ERR ; error
MOV A4,D.BUF(A4) ; D.BUF --> base of DDB
ADD #D.DDB,D.BUF(A4) ; D.BUF --> buffer area
MOV #512.,D.SIZ(A4) ; set buffer size
CLR D.DVR(A4) ; no driver
ORB #D$INI,D.FLG(A4) ; set buffer inited flag
; WARNING!!! - DEVICE DRIVER MUST BE IN MEMORY OR ALL THIS WILL BLOW UP IN
; YOUR FACE!
DSKFRE @A4,@A5 ; get free space on device
BEQ OK ; no error
ERR: CLR D1 ; clear contiguous blocks
MOV D1,DF.HOL(A5) ; ...
MOVB D.ERR(A4),D1 ; set error code in total blocks
MOV D1,DF.FRE(A5) ; ...
OK:
MOV Bas.A2(A3),A1 ; A1 -> contiguous space result
FLTOF DF.HOL(A5),@A1 ; return contiguous space
MOV Bas.A3(A3),A1 ; A1 -> total space result
FLTOF DF.FRE(A5),@A1 ; return total space
