Simtel MSDOS 1992 December

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/ Simtel MSDOS 1992 December / simtel1292_SIMTEL_1292_Walnut_Creek.iso / msdos / pcmag / vol6n02.arc / DIRCOMP.ASM next >

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Assembly Source File | 1987-12-13 | 13KB | 427 lines

; DIRCOMP.ASM -- Lists two directories side by side ; ================================================= CSEG Segment Assume CS:CSEG, DS:CSEG, ES:CSEG, SS:CSEG Org 0080h Parameter Label Byte ; Parameter is here Org 0100h Entry: Jmp Begin ; Entry Point ; Most Data (some more at end of program) ; --------------------------------------- db "Copyright 1986 Ziff-Davis Publishing Co.",1Ah db " Programmed by Charles Petzold ",1Ah SyntaxMsg db "Syntax: DIRCOMP filespec filespec$" DosVersMsg db "DIRCOMP: Needs DOS 2.0 +$" FileSpecMsg db "DIRCOMP: Bad file name$" TooManyMsg db "DIRCOMP: Too many files$" MemAllocMsg db "DIRCOMP: Not enough memory$" Delimiters db 9,' ,;=' FileList1 dd 0, ? ; Storage of found files FileList2 dd 0, ? FileCount1 dw 0 ; Count of found files FileCount2 dw 0 Append db '\*.*', 0 ; Check DOS Version ; ----------------- Begin: Mov AH, 30h ; Check for DOS Version Int 21h ; through DOS call Cmp AL, 2 ; See if it's 2.0 or above Jae DosVersOK ; If so, continue Mov DX, Offset DosVersMsg ; Error message ErrorExit: Mov AH, 9 ; Print String function call Int 21h ; Do it Int 20h ; And exit prematurely ; Parse Command Line to get file specifications ; --------------------------------------------- DosVersOK: Cld ; Directions forward Mov SI, Offset Parameter ; Parameter string Lodsb ; Length of Parameter Mov BL, AL ; Make BX the length Sub BH, BH Mov Word Ptr [SI + BX], 0D20h ; Put blank at end Mov DI, Offset FileSpec1 ; Destination of first spec Call GetFileSpec ; Transfer it and fix it up Mov DI, Offset FileSpec2 ; Destination of second spec Call GetFileSpec ; Transfer it and fix it up ; De-Allocate rest of memory ; -------------------------- Mov DX, Offset MemAllocMsg ; Possible error message Mov SP, Offset StackTop ; Bring in stack pointer Mov BX, SP ; Also end of needed memory Add BX, 15 ; Add 15 for truncation Mov CL, 4 ; Shift 4 bits right Shr BX, CL Mov AH, 4Ah ; Change memory size Int 21h ; through DOS Jc ErrorExit ; If problem, terminate ; Find Files from file specification ; ---------------------------------- Mov DX, Offset DTABuffer ; Set File Find buffer Mov AH, 1Ah ; by calling DOS Int 21h Mov DX, Offset FileSpec1 ; First file specification Call GetFilesAndSort ; Do as it says Mov Word Ptr [FileList1 + 2], AX ; Segment of file list Mov [FileCount1], CX ; Number of files Mov DX, Offset FileSpec2 ; Second file specification Call GetFilesAndSort ; Do it again Mov Word Ptr [FileList2 + 2], AX ; Segment of file list Mov [FileCount2], CX ; Number of files ; Now Display List on Screen ; -------------------------- DoAnother: Lea DI, DisplayString ; Destination of display line Mov AL, ' ' Cmp [FileCount1],0 ; See if any more left Jz FirstColDone ; If so, first column is blank Cmp [FileCount2],0 ; See if second is done Jz ListOnly1 ; If so, 2nd column is blank Push SI Push DI Push DS Push ES Les DI, [FileList2] ; Address of second list Lds SI, [FileList1] ; Address of first list Mov CX, 12 ; Number of bytes to compare Repz Cmpsb ; Compare them Pop ES ; Get back registers Pop DS Pop DI Pop SI Jb ListOnly1 ; If file 1 < file 2, list 1 Ja ListOnly2 ; If file 1 > file 2, list 2 Call ListFile1 ; Put first in display string Stosb ; Put a blank after it Jmp Short DoSecond ; Now do second file FirstColDone: Cmp [FileCount2], 0 ; See if second done also Jz AllDone ; If so, we're done ListOnly2: Mov CX, 40 ; If not, store 40 blanks Rep Stosb DoSecond: Call ListFile2 ; Put 2nd file in display str Jmp Short WriteCRLF ; And append a CR/Lf ListOnly1: Call ListFile1 ; Put 1st file in display str Mov CX, 40 ; Blank out second half Rep Stosb WriteCRLF: Mov AX, 0A0Dh ; Put CR/LF at end of string Stosw SpillOut: Lea DX, DisplayString ; Address of display string Mov CX, 81 ; Number of characters Mov BX, 1 ; Standard output Mov AH, 40h ; Write to screen Int 21h ; through DOS Jmp DoAnother ; And do the next one AllDone: Int 20h ; All done -- terminate ; SUBROUTINE: Get File Spec (uses DI to point to destination) ; ----------------------------------------------------------- GetFileSpec: Mov DX, DI ; Save pointer in DX Search: Call ScanParam ; Check next byte Je Search ; If delimiter, keep searching SearchEnd: Stosb ; Save the character Call ScanParam ; Check the next byte Jne SearchEnd ; If not delimiter, continue Mov Byte Ptr [DI], 0 ; Make it an ASCIIZ string Push SI ; Save parameter pointer Mov SI, 1 + Offset Append ; Set to *.* string Mov CX, 4 ; Possible 4 bytes to move Cmp Byte Ptr [DI - 1], ':' ; Do it if last character is : Jz AppendStuff Cmp Byte Ptr [DI - 1], '\' ; Or if last character is \ Jz AppendStuff Mov AX, 4300h ; Get file attribute Int 21h ; through DOS Jc FixUpDone ; If error, do no more Test CL, 10h ; See if it's directory Jz FixUpDone ; If not, do no more Dec SI ; If so, append \*.* Inc CX ; which has five characters AppendStuff: Rep Movsb ; Append string to file spec FixUpDone: Pop SI ; And done with this stuff Ret ; SUBROUTINE: Scan Parameter ; -------------------------- ScanParam: Push DI ; Save destination pointer Lodsb ; Get byte from parameter Cmp AL, 13 ; See if end of parameter Jne NotAtEnd ; If so, got an error Mov DX, Offset SyntaxMsg ; Load up error message Jmp ErrorExit ; and exit NotAtEnd: Mov DI, Offset Delimiters ; Check if delimiter Mov CX, 5 ; There are 5 of them Repne Scasb ; Scan the string Pop DI ; Get back pointer Ret ; And return ; SUBROUTINE: Get Files and Sort ; ------------------------------ GetFilesAndSort:Push ES Mov BX, 1000h ; Try to allocate 64K memory Mov AH, 48h ; through DOS Int 21h Jnc AllocateOK ; If no error, we've got it Mov AH, 48h ; Otherwise allocate Int 21h ; as much as possible AllocateOK: Mov CL, 4 ; Turn BX into an offset Shl BX, CL Sub BX, 20 ; Take away 20 bytes Mov ES, AX ; Set ES to memory segment Sub DI, DI ; Point to beginning Sub BP, BP ; File Counter Mov CX, 06h ; Normal, hidden, system files Mov AH, 4Eh ; Find first file FindFile: Int 21h ; Call DOS to find file Jnc Continue ; If no error continue Cmp AX, 18 ; If no more files Jz NoMoreFiles ; get out of the loop Mov DX, Offset FileSpecMsg ; Error message otherwise Jmp ErrorExit ; Exit and print message Continue: Cmp DI, BX ; See if end of segment Jb StillOK ; If not, continue TooManyFiles: Mov DX, Offset TooManyMsg ; Otherwise error message Jmp ErrorExit ; And terminate StillOK: Inc BP ; Kick up file counter Mov SI, 30+Offset DTABuffer ; Points to filename Mov CX, 12 ; 12 bytes to transfer TransName: Lodsb ; Get a byte Or AL, AL ; See if it's zero Jz NameDone ; If so, transfer done Cmp AL, '.' ; See if it's period Jnz NotPeriod ; If not keep going Sub CX, 3 ; If period, adjust counter Mov AL, ' ' ; Pad names with blanks Rep Stosb Add CX, 3 ; Re-adjust counter Jmp TransName ; And continue NotPeriod: Stosb ; If not period, just store it Loop TransName ; And keep going NameDone: Mov AL, ' ' ; Pad end of name with blanks Rep Stosb Mov SI, 22+Offset DTABuffer ; Point to time/date/size Mov CX, 4 ; Save that stuff too Rep Movsw Mov AH, 4Fh ; Find next file Jmp FindFile NoMoreFiles: Mov BX, DI ; End of file storage Add BX, 15 ; Convert to paragraph Mov CL, 4 Shr BX, CL Mov AH, 4Ah ; Re-adjust memory Int 21h ; Sort Files ; ---------- Push DS ; Save DS Push ES Pop DS ; Point DS to files Sub DI, DI ; This is the beginning Mov CX, BP ; Number of files to sort Jcxz AllSorted ; If no files, we're done Dec CX ; Loop needs one less than CX Jcxz AllSorted ; But zero means only one file SortLoop1: Push CX ; Save the file counter Mov SI, DI ; Set source to destination SortLoop2: Add SI, 20 ; Set source to next file Push CX ; Save the counter, Push SI ; compare source, Push DI ; and compare destination Mov CX, 20 ; 20 characters to compare Repz Cmpsb ; Do the compare Jae NoSwitch ; Jump if already in order Pop DI ; Get back these registers Pop SI Push SI ; And push them again for move Push DI Mov CX, 20 ; 20 characters SwitchLoop: Mov AL, ES:[DI] ; Character from destination Movsb ; Source to destination Mov DS:[SI - 1], AL ; Character to source Loop SwitchLoop ; For the rest of the line NoSwitch: Pop DI ; Get back the registers Pop SI Pop CX Loop SortLoop2 ; And loop for next file Pop CX ; Get back file counter Add DI, 20 ; Compare with next file Loop SortLoop1 ; And loop again AllSorted: Pop DS ; Get back to normal Mov AX, ES ; File segment in AX Pop ES Mov CX, BP ; File count in CX Ret ; SUBROUTINES for listing files on screen ; --------------------------------------- ListFile1: Push DS Lds SI, [FileList1] ; Set to address of list Call ListFile ; Put it into DisplayString Pop DS Mov Word Ptr [FileList1], SI ; Save new pointer Dec [FileCount1] ; Decrement count Ret ListFile2: Push DS Lds SI, [FileList2] ; Set to address of list Call ListFile ; Put it into DisplayString Pop DS Mov Word Ptr [FileList2], SI ; Save new pointer Dec [FileCount2] ; Decrement count Ret ListFile: Push AX Push SI Push DI Mov CX, 12 ; 12 characters in file name Rep Movsb ; Transfer them Mov AL, ' ' ; Blank out the rest Mov CX, 27 Rep Stosb Sub DI, 6 ; Point to time destination Lodsw ; Get the coded time Mov BL, 01Fh ; AND mask for hours Mov BH, '0' ; Zero-blank indicator Mov CL, 11 ; Shift value for hours Sub DL, DL ; Offset for hours Mov DH, ':' ; Following character Call DateTime ; Do the transfer routine Mov BX, 3Fh ; Zero OK / AND Mask for minutes Mov CL, 5 ; Shift value of minutes Mov DH, ' ' ; Following character Call DateTime ; Do the transfer routine Sub DI, 16 ; Point to date destination Lodsw ; Get the coded date Mov BL, 0Fh ; AND mask for month Mov BH, '0' ; Zero-blank indicator Mov CL, 5 ; Shift value for month Mov DH, '-' ; Following character Call DateTime ; Do the transfer routine Mov BX, 1Fh ; Zero OK / AND mask for day Mov CL, 0 ; Shift value for day Call DateTime ; Do the transfer routine Mov BL, 7Fh ; AND mask for year Mov CL, 9 ; Shift value for year Mov DL, 80 ; Offset for year Mov DH, ' ' ; Following character Call DateTime ; Do the transfer routine Sub DI, 12 ; Point to end of file size space Lodsw ; Get low word Mov DX, AX ; Save it in DX Lodsw ; AX is high word, DX low word Mov BX, 10 ; Will divide by 10 for ASCII Std ; Direction backward AsciiLoop: Mov CX, DX ; Save low word in CX Sub DX, DX ; Zero out DX for division Div BX ; AX = quotient, DX = remainder Xchg AX, CX ; Now AX = low word, CX = quotient1 Div BX ; AX = quotient2, DX = remainder Xchg AX, DX ; AX = remainder, DX = quotient2 Add AL, '0' ; Adjust for ASCII Stosb ; Store it Mov AX, CX ; See if zero is left Or CX, DX Jnz AsciiLoop ; If not, continue Cld ; Get back to normal Pop DI Pop SI Pop AX Add SI, 20 ; Next file in list Add DI, 39 ; Next byte in destination Ret ; SUBROUTINE: Date and Time Display ; --------------------------------- DateTime: Push AX Push BX Push CX Push DX Shr AX, CL ; Shift word left by CL bits And AL, BL ; AND it with BL mask Add AL, DL ; Offset it by DL Sub AH, AH ; Zero out high byte Mov BL, 10 ; Divide by 10 Div BL Add AX, '00' ; Convert to ASCII Cmp AL, BH ; Check Zero-Blank Jnz LeadingNonZero Mov AL, ' ' ; Put in blank instead of zero LeadingNonZero: Stosw ; Store the two bytes Mov AL, DH ; Get following character Stosb ; Store that also Pop DX Pop CX Pop BX Pop AX Ret ; Variable length data stored at end ; ---------------------------------- Even FileSpec1 Label Byte FileSpec2 equ FileSpec1 + 80 DTABuffer equ FileSpec2 + 80 DisplayString equ DTABuffer + 43 EndOfData equ DisplayString + 81 StackTop equ EndOfData + 200h CSEG EndS ; End of the segment End Entry ; Denotes entry point