path: root/v4.0/src/CMD/TREE/TREE.ASM

	PAGE	90,132			;AN000;A2
	TITLE	TREE.SAL - DISPLAY THE SUBDIRECTORY TREE ;AN000;
LISTPARM =	1			;AN000;0=SUPPRESS LIST; 1=ALLOW LIST
;	.XLIST
;****************** START OF SPECIFICATIONS *****************************
; MODULE NAME: TREE

; DESCRIPTIVE NAME: Tree structure of subdirectories is displayed.

; FUNCTION: Displays to standard output a graphic representation
;	    of the subdirectory tree structure, beginning
;	    with the specified subdirectory, and optionally
;	    displaying all filenames in that tree.

; ENTRY POINT: START

; INPUT: (DOS COMMAND LINE PARAMETERS)

;	      [d:][path] TREE [D:][path] [/F] [/A]

;	 WHERE
;	      [d:][path] - Path where the TREE command resides.

;	      [D:][path] - Display of subdirectories starts with this
;			   specified subdirectory.  If this is not
;			   specified, the default is the drive root directory.

;	      [/F]	 - This requests the files in each subdirectory
;			   in addition to the subdirectories themselves
;			   are to be listed.

;	      [/A]	 - This requests use of alternate graphic chars

; EXIT-NORMAL:	ERRORLEVEL 0 - Normal completion

; EXIT-ERROR:	ERRORLEVEL 1 - I/O error

;		ERRORLEVEL 2 - Incorrect DOS version

;		ERRORLEVEL 3 - Control Break termination

; EFFECTS: The result is a display of the Tree of subdirectories.
;	   No changes are made to the system, to the current subdirectory,
;	   nor to the current DOS default drive.

;		    1. NO FILES, JUST SUBDIRECTORIES

;		 D:\ROOT
;		 ����SUBDIR1
;		 ����SUBDIR2
;		 �   ����SUBDIR21
;		 �   ����SUBDIR22
;		 ����SUBDIR3
;		     ����SUBDIR31
;		     ����SUBDIR32

;		    2. FILES AND SUBDIRECTORIES

;		 D:\ROOT
;		 �   MAINFIL1
;		 �   MAINFIL2
;		 �
;		 ����SUBDIR1
;		 �	 FILE1
;		 �	 FILE2
;		 �
;		 ����SUBDIR2
;		 �   �	 FILE2A
;		 �   �	 FILE2B
;		 �   �
;		 �   ����SUBDIR21
;		 �   �	     FILEA
;		 �   �	     FILEB
;		 �   �
;		 �   ����SUBDIR22
;		 �	     FILEC
;		 �	     FILED
;		 �	     FILEF
;		 �
;		 ����SUBDIR3
;		     ����SUBDIR31
;		     ����SUBDIR32
;			     FILE32A
;			     FILE32B

; INCLUDED FILES: TREEQU.INC - EQUATES
;		  PATHMAC.INC - PATHGEN MACRO

; INTERNAL REFERENCES:
;    ROUTINES:

;     BEGIN - VERSION CHECK, SYSMSG INIT, EXIT TO DOS
;     DEFINE_GRAPHICS - GET GRAPHIC CHARS FROM MSG
;     PARSE - TOKENIZE THE DOS COMMAND LINE PARMS
;     VERIFY_DRIVE - CHECK IF USER DRIVE ID IS OK
;     INIT_CONDITIONS - GET INITIAL SUBDIR, APPEND,CTL_BREAK
;     GET_VOL_LABEL - GET VOLUME LABEL ON SPECIFIED DRIVE
;     VOLSER - DISPLAY VOLUME SERIAL NUMBER, IF ANY AN001
;     LEN_ASCIIZ - GET LENGTH OF ASCIIZ STRING
;     EXECUTE - LOOK THRU DIRECTORY LIST FOR SUBDIRS
;     ANY_MORE_SUBDIR - LOOK AHEAD,SEE IF MORE SUBDIR
;     FIND_TYPE_NORMAL - PROCESS NORMAL, NON-DIR, FILES
;     FIND_TYPE_DIR - PROCESS THE DIRECTORY
;     NEXT_LEVEL - SET UP TO LOOK AT LOWER LEVEL SUBDIR
;     BEGIN_FIND - DO FIND FIRST FILE
;     FIND_NEXT - LOOK FOR NEXT ENTRY IN DIRECTORY
;     SHOW_FN - DISPLAY THE FILENAME FOUND
;     FLN_TO_BUF - MOVE FILENAME TO BUFFER
;     GRAF_TO_BUF - SELECT LEADING GRAPHIC CHAR FOR BUF
;     BLANK_DASH - PUT BLANKS OR DASHES BEFORE FILENAME
;     FIX_GRAF - CHANGE CURRENT GRAPHIC FOR NEXT LINE
;     ANY_SUBDIRS - DISPLAY MSG IF NO SUBDIRS PRINTED
;     DO_WRITE - SEND STRING TO STDOUT
;     IF_NOMOREFILES - ASK EXTENDED ERROR FOR WHY IS ERROR
;     GET_EXTERR - CALL EXTENDED ERROR
;     SENDMSG - PASS IN REGS DATA FROM MSG DESCRIPTOR TO DISP MSG
;     BREAK_HANDLER - CONTROL BREAK VECTOR POINTS HERE
;     RESTORE - RETURN TO INITIAL DOS DEFAULT DRIVE
;     MYERRORHANDLER - SERVICE CRITICAL ERROR HANDLER
;     CHK_DBCS -SEE IF SPECIFIED BYTE IS A DBCS LEAD BYTE

;    DATA AREAS:
;	PSP - Contains the DOS command line parameters.
;	STACK - Dynamic allocation of workareas.

; EXTERNAL REFERENCES:
;    ROUTINES:
;	SYSDISPMSG (FAR)  - MESSAGE DISPLAY ROUTINE
;	SYSLOADMSG (FAR)  - SYSTEM MESSAGE LOADER
;	PARSER	   (NEAR) - INTERROGATE DOS COMMAND LINE PARMS

;    DATA AREAS:
;	DTA - defined by the DOS FINDFIRST function.

; NOTES:
;	 This module should be processed with the SALUT pre-processor
;	 with the re-alignment not requested, as:

;		SALUT TREE,NUL

;	 To assemble these modules, the sequential or alphabetical
;	 ordering of segments may be used.

;	 Sample LINK command:

; LINK @TREE.ARF

; Where the TREE.ARF is defined as:
;	       TREE+
;	       TREEPAR+
;	       TREESYSP+
;	       TREESYSM
;	       TREE

;	 These modules should be linked in this order.	The load module is
;	 a COM file.  It should be converted via EXE2BIN to a .COM file.

; REVISION HISTORY: A000 Version 4.00: add PARSER, System Message Handler,
;		    Display graphically the subdirectories and their files.
;		    A001 DCR 27, display vol serial number, if present.
;		    A002 Add support for /A switch for alternate graphics.
;		    A003 PTM 471 Avoid duplicate switches
;		    A004 PTM 537 Display parm in error
;		    A005 PTM 692 Remove period from vol label field
;		    A006 PTR1044 Append interface change
;		    A007 PTM1082 Critical error handler
;		    A008 PTM1199 DEFAULT DIR OF TARGET ALTERED
;		    A009 PTM1416 INT24 CLOBBERED USER'S RESPONSE
;		    A010 PTM1406 GET MEDIA ID WITH 69H, NOT IOCTL
;		    A011 PTM1821 COPYRIGH.INC moved to within msgserv.asm
;		    A012 PTM2352 DBCS ENABLING, CHECKING FOR "\"
;		    A013 PTM3512 PATHGEN
;		    A014 PTM3560 INVALID PATH DOES NOT DISPLAY PATHNAME
;
;     Label: The following notice is found in the OBJ code generated from
;	     the "TREESYSM.SAL" module:

;	     "Version 4.00 (C) Copyright 1988 Microsoft
;	     "Licensed Material - Program Property of Microsoft

;****************** END OF SPECIFICATIONS *****************************
	IF1				;AN000;
	    %OUT    COMPONENT=TREE, MODULE=TREE.SAL... ;AN000;
	ENDIF				;AN000;
	HEADER	<MACRO DEFINITIONS>	;AN000;
	INCLUDE PATHMAC.INC		;AN013;
; =  =	=  =  =  =  =  =  =  =	=  =
FIXLIST MACRO	LP,DOIT 		;;AN000;
	IF	LP			;;AN000;
	    DOIT			;;AN000;
	ENDIF				;;AN000;
	ENDM				;;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
HEADER	MACRO	TEXT			;;AN000;
	FIXLIST LISTPARM,.XLIST 	;;AN000;
	SUBTTL	TEXT			;;AN000;
	FIXLIST LISTPARM,.LIST		;;AN000;
	PAGE				;;AN000;
	ENDM				;;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
;				   $SALUT (0,36,41,52) ;AN000;
DOSCALL 			   MACRO FN,SF	   ;;AN000;
				   IFNB <FN>	   ;;AN000;ARE THERE ANY PARMS AT ALL?
				   IFNB <SF>	   ;;AN000;
				   MOV	AX,(FN SHL 8)+SF ;;AN000;AH=FN;AH=SF
				   ELSE 	   ;;AN000;SINCE THERE IS NO SUB FUNC
				   MOV	AH,FN	   ;;AN000;
				   ENDIF	   ;;AN000;
				   ENDIF	   ;;AN000;
				   INT	21H	   ;;AN000;
				   ENDM 	   ;;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
;	     $SALUT (0,14,19,36)   ;AN000;
	     HEADER <EQUATES - DOS FUNCTION CALLS> ;AN000;
	     INCLUDE TREEQU.INC    ;AN000;EQUATES, CONTROL BLOCKS
; =  =	=  =  =  =  =  =  =  =	=  =
LISTPARM     =	  1		   ;AN000;PERMIT LISTING
.LIST				   ;AN000;
	     HEADER <STATIC DATA AREA> ;AN000;
CSEG	     SEGMENT PARA PUBLIC 'CODE' ;AN000;
	     ASSUME CS:CSEG,DS:CSEG,ES:CSEG,SS:CSEG ;AN000;AS SET BY DOS LOADER
; $SALUT (4,3,8,36)		   ;AN000;
  EXTRN SUBLIST_PARSE:WORD	   ;AN004;PARSE ERROR XX - %0

  EXTRN MSGNUM_VOL:WORD 	   ;AN000;"Directory PATH listing for Volume %1"
  EXTRN SUBLIST_VOL:WORD	   ;AN000;SUBLIST TO VOL LABEL IN FIX_DTA_FILN

  EXTRN MSGNUM_LIST:WORD	   ;AN000;"Directory PATH listing"

  EXTRN MSGNUM_INVPATH:WORD	   ;AN000;"INVALID PATH"
  EXTRN SUBLIST_INVPATH:WORD	   ;AN014;THE ASCIIZ PATH CONSIDERED INVALID

  EXTRN MSGNUM_EXTERR:WORD	   ;AN000;ALL EXTENDED ERRORS
  EXTRN MSGNUM_NOSUB:WORD	   ;AN000;"No subdirectories exists"

  EXTRN MSGNUM_SERNO:WORD	   ;AN001;"Volume Serial Number is %1-%2"
  EXTRN SUBLIST_6A:WORD 	   ;AN001;FIRST PART OF SERIAL NUMBER
  EXTRN SUBLIST_6B:WORD 	   ;AN001;SECOND PART OF SERIAL NUMBER

  EXTRN CURRENT_PARM:WORD	   ;AN000;POINT TO NEXT PARM TO PARSE
  EXTRN ORDINAL:WORD		   ;AN000;NUMBER OF CURRENT PARM
  EXTRN LAST_BYTE:BYTE		   ;AN000;TAG AT END OF USED MEMORY, BEFORE STACK

  EXTRN SYSDISPMSG:NEAR 	   ;AN000;MESSAGE DISPLAY ROUTINE
  EXTRN SYSLOADMSG:NEAR 	   ;AN000;SYSTEM MESSAGE LOADER
  EXTRN SYSGETMSG:NEAR		   ;AN002;SYSTEM MESSAGE LOCATER ROUTINE
  EXTRN PARSER:NEAR		   ;AN000;INTERROGATE DOS COMMAND LINE PARMS
; =  =	=  =  =  =  =  =  =  =	=  =
;	     $SALUT (0,14,19,36)   ;AN000;
	     ORG  80H		   ;AN000;
	     PUBLIC COMMAND	   ;AN000;
COMMAND      DB   128 DUP (?)	   ;AN000;DOS INPUT COMMAND LINE
; =  =	=  =  =  =  =  =  =  =	=  =
	     ORG  100H		   ;AN000;REQUIRED LOCATION OF ENTRY POINT
START:	     JMP  BEGIN 	   ;AN000;DOS ENTRY POINT
; =  =	=  =  =  =  =  =  =  =	=  =
;THERE ARE TWO SETS OF DEFINITIONS OF THE GRAPHIC CHARACTERS USED IN THE DISPLAY.
;THE FIRST SET LOOKS THE BEST, BUT ON SOME PRINTERS IS A TEDIOUS, SLOW PROCESS.
;THERE ARE SOME CODEPAGES THAT DO NOT HAVE THESE SAME GRAPHIC CHARACTERS IN
;THESE CORRESPONDING CODE POINT POSITIONS.  JAPAN HAS ITS KATAKANA CHARACTER
;SET WHERE THESE GRAPHICS ARE DEFINED, AND WOULD THUS NOT WANT TO USE THIS
;FIRST GRAPHIC CHARACTERS SET.	THE SECOND SET OF EQUATES DEFINE ALTERNATE
;CHARACTERS THAT, ALTHOUGH THE OUTPUT DOES NOT LOOK AS GOOD, AT LEAST WILL
;PRINT NORMALLY, AND DOES USE THE TRADITIONAL ASCII LOWER 128 AS ITS CODE
;POINTS, THUS WOULD BE AVAILABLE FOR THOSE OTHER CODEPAGES, LIKE JAPAN'S.

;IF IT BECOMES DESIRABLE TO GENERATE YET ANOTHER DEFINITION OF THESE CHARACTERS,
;THE REQUIREMENTS ARE:
;	1. NONE OF THE FOUR CAN BE BLANK
;	2. EACH OF THE FOUR MUST BE UNIQUE
;	3. EACH CHAR MUST BE A SINGLE BYTE (NO DBCS)

;		GRAPHIC CHARACTERS
;THIS SET OF GRAPHIC CHARACTERS ARE ACTUALLY DEFINED BY THE MESSAGE 7,
;WHERE TRANSLATORS HAVE PROVIDED THE CHARACTERS COMPATABLE WITH THEIR
;NATIONAL CHARACTER CODEPAGE SET.
GRAF_TABLE   LABEL BYTE 	   ;AN002;DEFINITION OF FOUR GRAPHIC CHARACTERS
	     PUBLIC GRAF_TABLE	   ;AN002;
GRAF_ELBO    DB   "�"		   ;AN000;192 DECIMAL ASCII VAL
GRAF_DASH    DB   "�"		   ;AN000;196 DECIMAL ASCII VALUE
GRAF_TEE     DB   "�"		   ;AN000;195 DECIMAL ASCII VALUE
GRAF_BAR     DB   "�"		   ;AN000;179 DECIMAL ASCII VALUE


;		ALTERNATE SET OF GRAPHIC CHARACTERS
;IF THE "/A" SWITCH IS SPECIFIED, THIS SET OF FOUR CHARACTERS WILL
;OVERLAY THE ABOVE SET OF GRAPHIC CHARACTERS.

GRAF_TABLE_ALT LABEL BYTE	   ;AN002;ALTERNATE SET OF GRAPHIC CHARACTERS
	     PUBLIC GRAF_TABLE_ALT ;AN002;
A_GRAF_ELBO  DB   "\"		   ;AN000;
A_GRAF_DASH  DB   "-"		   ;AN000;
A_GRAF_TEE   DB   "+"		   ;AN000;
A_GRAF_BAR   DB   "|"		   ;AN000;

; =  =	=  =  =  =  =  =  =  =	=  =
FLAGS	     DB   0		   ;AN000;INITIALIZE ALL FLAGS TO "FALSE"
	     PUBLIC FLAGS,F_SWITCH ;AN000;ADD ENTRIES IN LINK MAP
F_DEF_PAT_TAR EQU 40H		   ;AN008;IF ON, DEFAULT SUBDIR OF TARGET DRIVE IS KNOWN
				   ;IF OFF, DEF SUBDIR OF TARGET NOT KNOWN     ;AN008;
F_SUBDIR     EQU  20H		   ;AN000;IF ON, A SUBDIR HAS BEEN DISPLAYED
				   ;IF OFF, A SUBDIR HAS NOT YET BEED DISPLAYED
F_FAILING    EQU  10H		   ;AN000;IF ON, DO NOT RESTORE SUBDIR ON FAILING DRIVE
				   ;IF OFF, DO RESTORE SUBDIR ON TARGET DRIVE	;AN000;
F_FLN	     EQU  08H		   ;AN000;IF ON, A FILENAME HAS BEEN DISPLAYED
				   ;IF OFF, NO FILNAME FOR THIS SUBDIR YET
F_FIRSTIME   EQU  04H		   ;AN000;IF ON, DISPLAY OF NAME ALREADY DONE
				   ;IF OFF, DISPLAY OF NAME NEVER DONE
F_SWITCH     EQU  02H		   ;AN000;IF ON, THE /F SPECIFIED
				   ;IF OFF, THEN /F NOT SPECIFIED
F_APPEND     EQU  01H		   ;AC006;IF ON, DOS APPEND IS IN THE MULTIPLEXOR
				   ;IF OFF, DOS APPEND IS NOT THE MULTIPLEXOR

APPEND_FLAGS DW   0		   ;AN006;RECORDS ORIGINAL STATE OF APPEND
				   ;8000H = /X:1
				   ;4000H = /E
				   ;2000H = /PATH:1
				   ;1000H = /DRIVE:1
				   ;0001H = ENABLE APPEND

DBCSENV      DD   0		   ;AN000;POINTER TO DBCS RANGES
ORIG_AX      DW   0		   ;AN000;DRIVE VERIFICATION FROM DOS AT ENTRY
CURRENT_COL  DW   1		   ;AN000;IN BUF, WHERE IS ELBO/TEE?
				   ; INITIALLY SET TO START IN COLUMN ONE
MEDIA_ID_BUF A_MEDIA_ID_INFO <>    ;AN001;AREA TO READ VOL SERIAL NUMBER WITH GET_MEDIA_ID
BUF	     DB   ((DASH_NUM+1)*LEVEL_LIMIT) DUP(0) ;AN000;HAS ELBO,TEE,DASH,NUL ENDED
JUSTIN_CASE  DB   64 DUP(0)	   ;AN000;CATCHES THE OVERFLOW
CRLF	     DB   CR,LF,NUL	   ;AN000;LINE TERMINATOR
LEN_CRLF     EQU  2		   ;AN000;LENGTH OF CR, LF FIELDS IN PREVIOUS MSG
EXITFL	     DB   EXOK		   ;AN000;RETURN CODE, INITIALLY "NORMAL"
;	   (SEE INCLUDED FILE OF EQUATES FOR DEFINITIONS OF VALUES)

;		REMEMBER THE DOS DEFAULT DRIVE AND SUBDIRECTORY
DEFAULT_DR   DB   ?		   ;AN000;ALPHA LETTER OF DOS DEFAULT DRIVE
START_DR_NUM DB   ?		   ;AN000;NUMERIC VALUE OF DOS DEFAULT DRIVE
				   ; WHERE 0=A:, 1=B:, ETC...
DEFAULT_PATH DB   BACK_SLASH	   ;AN000;FIRST BYTE OF PATH IS BACKSLASH
	     DB   MAX_PATH DUP(0)  ;AN000;ORIGINAL DEFAULT PATH
JUSTIN_CASE2 DB   64 DUP(0)	   ;AN000;CATCHES THE OVERFLOW
OLDINT23     DD   ?		   ;AN000;ORIGINAL CONTENTS OF CTRL-BREAK VECTOR
OLDINT24     DD   ?		   ;AN000;ORIGINAL CONTENTS OF CRITICAL ERROR VECTOR

FIX_DTA_RES  DB   21 DUP(?)	   ;AN000;RESERVED FOR FIND NEXT CALLS
FIX_DTA_ATTR DB   ?		   ;AN000;ATTRIBUTE
FIX_DTA_TIME DW   ?		   ;AN000;TIME
FIX_DTA_DATE DW   ?		   ;AN000;DATE
FIX_DTA_LSIZ DW   ?		   ;AN000;LOW WORD OF FILE SIZE
FIX_DTA_HSIZ DW   ?		   ;AN000;HIGH WORD OF FILE SIZE
FIX_DTA_FILN DB   13 DUP(?)	   ;AN000;FILENAME, WITH PERIOD, +0 BYTE
	     PUBLIC FIX_DTA_FILN   ;AN000;USED TO DISPLAY VOLUME LABEL
STAR_STAR    DB   "*.*",0	   ;AN000;UNIVERSAL FILENAME, +0
STAR_STAR_L  EQU  $-STAR_STAR	   ;AN000;LENGTH OF UNIVERSAL FILENAME, INCL NUL
SAVEFILN     DB   13 DUP(?)	   ;AN000;COPY OF FIX_DTA_FILN, ABOVE
;	 THIS NEXT SET OF WORKSPACE DEFINES THE PATH BEING PROCESSED.
;	 THESE ITEMS MUST REMAIN TOGETHER, IN THIS ORDER:
START_DRIVE  DB   0,":" 	   ;AN000;DRIVE LETTER NEEDS TO BE FILLED IN HERE
	     PUBLIC START_DRIVE,START_PATH ;AN000;
START_PATH   DB   PERIOD	   ;AN000;AREA TO RECEIVE STARTING PATH ASCIIZ
	     DB   (MAX_PATH+SIZE FIX_DTA_FILN) DUP(0) ;AN000;
JUSTIN_CASE3 DB   64 DUP(0)	   ;AN000;CATCHES THE OVERFLOW
;	END OF CONTIGUOUS WORKSPACE DEFINING PATH
; =  =	=  =  =  =  =  =  =  =	=  =
	     PATHLABL TREE	   ;AN013;
	     HEADER <BEGIN - VERSION CHECK, SYSMSG INIT, EXIT TO DOS> ;AN000;
; $SALUT (4,3,8,36)		   ;AN000;
BEGIN PROC NEAR 		   ;AN000;
  PUBLIC BEGIN			   ;AN000;
;INPUT - DOS COMMAND LINE PARMS, AS DEFINED IN MODULE PROLOG.
;	  CONTROL IS PASSED HERE FROM "START" AT ORG 100H.
;	 AX IS SET BY DOS TO FLAG ANY INVALID DRIVE SPECIFIED ON PARMS.
;OUTPUT - "EXITFL" HAS ERRORLEVEL RETURN CODE
; =  =	=  =  =  =  =  =  =  =	=  =

  MOV  ORIG_AX,AX		   ;AN000;SAVE ORIGINAL VALUE OF AX

;SINCE THIS IS A .COM STYLE UTILITY, THE SEG ID IN THE MSG SUBLIST
;CANNOT BE SET BY THE LOADER, BUT MUST BE SET HERE, AT RUN TIME.

  MOV  SUBLIST_VOL.SUB_VALUE_SEG,CS ;AN000;MAKE SUBLIST VARIABLE ADDRESSABLE
  MOV  SUBLIST_6A.SUB_VALUE_SEG,CS ;AN001;
  MOV  SUBLIST_6B.SUB_VALUE_SEG,CS ;AN001;
  MOV  SUBLIST_PARSE.SUB_VALUE_SEG,CS ;AN004;
  MOV  SUBLIST_INVPATH.SUB_VALUE_SEG,CS ;AN014;

  CALL SYSLOADMSG		   ;AN000; INIT SYSMSG HANDLER

; $IF  C			   ;AN000; IF THERE WAS A PROBLEM
  JNC $$IF1
      CALL SYSDISPMSG		   ;AN000; LET HIM SAY WHY HE HAD A PROBLEM

      MOV  EXITFL,EXVER 	   ;AN000; TELL ERRORLEVEL BAD DOS VERSION
; $ELSE 			   ;AN000; SINCE SYSDISPMSG IS HAPPY
  JMP SHORT $$EN1
$$IF1:
      CLD			   ;AN000;CLEAR DIRECTION FLAG TO AUTO-INCREMENT

;		GET CURRENT DRIVE ID
      DOSCALL CURRDISK		   ;AN000;(19H) SET AL=0 IF A:, 1 IF B:, ETC...

      MOV  START_DR_NUM,AL	   ;AN000;SAVE NUMERIC VALUE OF DOS DEFAULT DRIVE
      ADD  AL,DRIVEA		   ;AN000;CONVERT DRIVE NUMBER TO LETTER
      MOV  DEFAULT_DR,AL	   ;AN000;REMEMBER ALPHA OF DEFAULT DRIVE
				   ; OF FILENAME TO BE SEARCHED FOR
;		    RECORD THE INITIAL SET UP
      CALL INIT_CONDITIONS	   ;AC007;SET DTA,APPEND STATUS,CAPTURE CTL-BREAK VEC


      CALL DEFINE_GRAPHICS	   ;AN002;GET PROPER GRAPHIC CHARS FROM MSG

      CALL PARSE		   ;AN000;LOOK AT DOS COMMAND LINE PARAMETERS,
				   ; AND DISPLAY ERR MSG IF BAD
;     $IF  NC			   ;AN000;PARMS ARE OK?
      JC $$IF3
;	    CURIOUS ODDITY:
;	    "CURRDISK"	  AL=0 DRIVE A:,      AL=1 DRIVE B: ETC...
;	    "GET_CUR_DIR" AL=0 DEFAULT DRIVE, AL=1 DRIVE A: ETC...
;	    "SELECT_DISK" AL=0 DRIVE A:,      AL=1 DRIVE B: ETC...
;	    SO... THE NUMBER WE HAVE HERE AGREES WITH "SELECT_DISK", BUT
;	    WE MUST ADD ONE WHEN WE DO THE "GET_CUR_DIR".

;		GET CURRENT DIRECTORY OF TARGET DRIVE
				   ;DS:SI = POINTER TO 64 BYTE USER AREA
				   ;DL = DRIVE NUM (0=DEF, 1=A, ETC)
				   ;OUTPUT: DS:SI POINTS TO FULL PATH NAME
; "DEFAULT_PATH" WILL HAVE THE DOS DEFAULT SUBDIRECTORY PATH.

	  MOV  SI,OFFSET DEFAULT_PATH+1 ;AN000;PASS 64 BYTE AREA
	  MOV  DL,START_DRIVE	   ;AN000;PASS NUMERIC VALUE
	  SUB  DL,DRIVEA	   ;AN000;  OF DRIVE TO BE SCANNED
	  INC  DL		   ;AN000;SEE "CURIOUS ODDITY" ABOVE...
	  DOSCALL GET_CUR_DIR	   ;AN000;(47H) GET THE CURRENT SDIR OF TARGET DRIVE

	  OR   FLAGS,F_DEF_PAT_TAR ;AN008;INDICATE DEFAULT PATH OF TARGET IS KNOWN


;		     DISPLAY FUNCTION HEADER
	  CALL GET_VOL_LABEL	   ;AN000;GET VOLUME LABEL TO FIX_DTA_FILN

;		     DISPLAY VOLUME SERIAL ID
	  CALL EXECUTE		   ;AN000;DISPLAY THE SET OF SUBDIRS

	  CALL ANY_SUBDIRS	   ;AN000;DISPLAY FINAL MSG IN CASE NO SUBDIRS

;     $ELSE			   ;AN000;SINCE PARMS HAD A PROBLEM,
      JMP SHORT $$EN3
$$IF3:
	  MOV  EXITFL,EXERR	   ;AN000;SET ERROR RETURN CODE
;     $ENDIF			   ;AN000;PARMS OK?
$$EN3:
;		     RESTORE SYSTEM TO INITIAL CONDITIONS
      CALL RESTORE		   ;AN007;RETURN TO INITIAL DOS DEFAULT DRIVE,
				   ; THE INITIAL DEFAULT PATH,
				   ; AND THE INITIAL "APPEND" STATE.
; $ENDIF			   ;AN000;OK WITH SYSDISPMSG?
$$EN1:

  MOV  AL,EXITFL		   ;AN000;PASS BACK ERRORLEVEL RET CODE
  DOSCALL RET_CD_EXIT		   ;AN000;(4CH) RETURN TO DOS WITH RET CODE

  INT  20H			   ;AN000; IF ABOVE NOT WORK, EXIT ANYWAY

;FOR CONTROL-BREAK, "TREE" WILL EXIT TO DOS AT "CTL_BREAK" PROC
; IN STEAD OF HERE.
BEGIN ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <DEFINE_GRAPHICS - GET GRAPHIC CHARS FROM MSG> ;AN002;
DEFINE_GRAPHICS PROC NEAR	   ;AN002;
  PUBLIC DEFINE_GRAPHICS	   ;AN002;
;INPUT - MESSAGE 7 HAS THE FOUR GRAPIC CHARS, DEFINED BY THE TRANSLATORS
;	 TO BE ACCEPTABLE TO THIS NATIONAL CODEPAGE.
;OUTPUT- THE "GRAF_TABLE" AREA IS Revised TO HAVE THE 4 GRAPHIC CHARS
;	 AS DEFINED BY THE MESSAGE
; =  =	=  =  =  =  =  =  =  =	=  =
;		DEFINE THE GRAPHIC CHARACTERS
  MOV  AX,GRAPHIC_MSGNUM	   ;AN002;REQUEST THE MESSAGE WITH GRAPHIC CHAR DEFS
  MOV  DH,UTILITY_MSG_CLASS	   ;AN002;
  CALL SYSGETMSG		   ;AN002;ASK WHERE THOSE GRAPHIC CHARS ARE
				   ;IF ANY PROBLEM HERE, JUST LEAVE
				   ; THE GRAPHICS AS DEFINED AT ASSEMBLY TIME.
; $IF  NC			   ;AN002;IF ALL OK, DS:SI POINTS TO MESSAGE
  JC $$IF7
      LEA  DI,GRAF_TABLE	   ;AN002;POINT TO WHERE GRAPHIC CHARS ARE TO GO
      LODSW			   ;AN002;GET FIRST PAIR OF CHARS
      STOSW			   ;AN002;SAVE THEM
      LODSW			   ;AN002;GET SECOND PAIR OF CHARS
      STOSW			   ;AN002;AND SAVE THEM ALSO
; $ENDIF			   ;AN002;
$$IF7:
  RET				   ;AN002;
DEFINE_GRAPHICS ENDP		   ;AN002;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <PARSE - TOKENIZE THE DOS COMMAND LINE PARMS> ;AN000;
PARSE PROC NEAR 		   ;AN000;
  PUBLIC PARSE			   ;AN000;
;INPUT - PSP HAS DOS COMMAND LINE PARAMETERS
;OUTPUT- CARRY IS SET IF THERE IS A PROBLEM
;	 CARRY IS CLEAR IF PARMS ARE OK

;	 IF THERE WERE ANY PARMS, THEY ARE MOVED FROM THE PSP
;	   INTO THE STRING, "COMMAND", WHERE THE PARSER WILL LOOK AT THEM.

;	 IF THE SWITCH "/F" WAS SPECIFIED, "F_SWITCH" IS SET TO "ON"
;	 IF THE SWITCH IS NOT SPECIFIED, "F_SWITCH" IS LEFT "OFF".

;	 IF THERE ARE NO PARMS, THE DEFAULTS OF CURRENT DRIVE AND CURRENT
;	   SUBDIRECTORY ARE SET UP TO BE WHERE THE SUBDIR SEARCH WILL
;	   START, AND THE "/F" SWITCH IS ASSUMED NOT SPECIFIED, SO
;	   THE DEFAULT DISPLAY WILL SHOW SUBDIRS ONLY, NO FILES.

;	 "START_DRIVE" EITHER HAS THE SPECIFIED STARTING DRIVE, OR
;		WILL HAVE THE CURRENT DOS DEFAULT DRIVE.
;	 "START_PATH" EITHER WILL HAVE THE SPECIFIED STARTING PATH, OR
;		WILL HAVE THE CURRENT DEFAULT PATH
; =  =	=  =  =  =  =  =  =  =	=  =

  MOV  CURRENT_PARM,OFFSET COMMAND+1 ;AN000;SET POINT TO BEGINNING OF STRING
  MOV  ORDINAL,ZERO		   ;AN000;START WITH FIRST PARM
  CALL PARSER			   ;AN000;INTERROGATE THE DOS COMMAND LINE PARMS
				   ;OUTPUT: SET CARRY IF PROBLEM
				   ;	    CLEAR CARRY IF ALL OK
; $IF  NC			   ;AN000;IF ALL OK SO FAR WITH PARSER,
  JC $$IF9
      CMP  START_DRIVE,NUL	   ;AN000;SEE IF START_DRIVE FILLED IN YET
;     $IF  E			   ;AN000;NO, NOT FILLED IN YET
      JNE $$IF10
	  MOV  AL,DEFAULT_DR	   ;AN000;GET ALPHA LETTER OF DEFAULT DRIVE
	  MOV  START_DRIVE,AL	   ;AN000;SET WHERE TO SEARCH FOR SUBDIRS
	  CLC			   ;AN000;NO ERROR SO FAR
;     $ELSE			   ;AN000;SINCE START_DRIVE WAS SPECIFIED
      JMP SHORT $$EN10
$$IF10:
	  CALL VERIFY_DRIVE	   ;AN000;SEE IF USER SPECIFIED DRIVE IS OK, AND
				   ; IF SO, CHANGE DOS DEFAULT DRIVE TO IT
				   ;CARRY WILL BE SET IF ERROR

				   ;IF A NEW DRIVE WAS SPECIFIED,
				   ; DEFAULT DRIVE HAS BEEN CHANGED TO
				   ; NEW DEFAULT DRIVE, USER SPECIFIED

;     $ENDIF			   ;AN000;FILLED IN START_DRIVE YET?
$$EN10:
;     $IF  NC			   ;AN000;IF ALL OK SO FAR,
      JC $$IF13
	  CMP  START_PATH,NUL	   ;AN000;SEE IF START_PATH FILLED IN YET
;	  $IF  E		   ;AN000;NO, NOT FILLED IN YET,
	  JNE $$IF14
	      MOV  DI,OFFSET START_PATH ;AN000;SET WHERE TO PUT STARTING PATH
	      MOV  AL,BACK_SLASH   ;AN000;START CURRENT SUBDIR AT ROOT
	      STOSB		   ;AN000;  SO START WITH BACK SLASH

				   ;DI POINTS TO BYTE AFTER BACK SLASH
				   ; JUST ADDED TO "START_PATH"

	      MOV  SI,DI	   ;AN000;DS:SI = POINTER TO 64 BYTE USER AREA
	      MOV  DL,DEFDRIVE	   ;AN000;DL = DRIVE NUM (0=DEF, 1=A, ETC)
	      DOSCALL GET_CUR_DIR  ;AN000;(47H) GET CURRENT DIRECTORY
				   ;OUTPUT: DS:SI POINTS TO FULL PATH NAME
;	  $ENDIF		   ;AN000;START_PATH FILLED IN YET?
$$IF14:
	  CLC			   ;AN000;INDICATE NO PROBLEM WITH PARMS
;     $ENDIF			   ;AN000;ALL OK SO FAR?
$$IF13:
; $ENDIF			   ;AN000;ALL OK WITH PARSER?
$$IF9:
  RET				   ;AN000;RETURN TO CALLER
PARSE ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <VERIFY_DRIVE - CHECK IF USER DRIVE ID IS OK> ;AN000;
VERIFY_DRIVE PROC NEAR		   ;AN000;
  PUBLIC VERIFY_DRIVE		   ;AN000;
;THE USER HAS SPECIFIED A DRIVE LETTER.  VERIFY IT IS A PROPER DRIVE.
;IF THE DRIVE LETTER SPECIFIED IS THE SAME AS THE DEFAULT DRIVE, IT IS OK.
;IF DIFFERENT, ADDITIONAL VERIFICATION TESTS MUST BE MADE.
;THIS TEST IS DONE BY TRYING TO CHANGE THE CURRENT DRIVE TO THE SPECIFIED
; DRIVE, THEN BY ASKING WHAT IS THE CURRENT DRIVE.  IF THE CURRENT DRIVE
; HAS CHANGED FROM WHAT IT WAS ORIGINALLY, THEN THE NEW DRIVE LETTER IS OK.
; IF IT DID NOT CHANGE, THEN IT WAS A BOGUS DRIVE LETTER AND WE QUIT.

;INPUT: "START_DRIVE" - USER SPECIFIED DRIVE LETTER TO BE TESTED
;	"DEFAULT_DR" - ORIGINAL DOS DEFAULT DRIVE
;	"START_DR_NUM" - NUMERIC EQUIVALENT OF THE ORIGINAL DOS DEFAULT DRIVE
;	"ORIG_AX" - HAS FLAGS TO VERIFY DRIVE, SET BY DOS AT LOAD TIME.
;OUTPUT: CARRY SET IF BAD, CARRY CLEAR IF OK
;	IF BAD, ERROR MESSAGE IS DISPLAYED: "INVALID DRIVE SPECIFICATION"
; =  =	=  =  =  =  =  =  =  =	=  =
  MOV  DL,START_DRIVE		   ;AN000;USING THE DRIVE SPECIFIED IN PARMS,
  CMP  DL,DEFAULT_DR		   ;AN000;DID PARMS SPECIFY DRIVE SAME AS DEFAULT?
; $IF  NE			   ;AN000;IF DRIVE SPECIFIED IS DIFFERENT
  JE $$IF18
      MOV  AX,ORIG_AX		   ;AN000;GET DRIVE VERIFICATION FLAGS, SAVED FROM AX
      OR   AL,AH		   ;AN000;COMBINE FLAGS FOR BOTH DRIVE ID'S, IF GIVEN
;     $IF  NZ,OR		   ;AN000;IF THERE IS A PROBLEM, OR...
      JNZ $$LL19

      SUB  DL,DRIVEA		   ;AN000;CONVERT DRIVE LETTER TO DRIVE NUMBER
				   ; DL=DRIVE NUMBER (0=A,1=B)
      DOSCALL SELECT_DISK	   ;AN000;(0EH) SET DEFAULT DRIVE
				   ;OUTPUT: AL=NUM. OF DRIVES (MIN 5) (NOT USED);AN000;
				   ; (NOT INTERESTED...)
      DOSCALL CURRDISK		   ;AN000;(19H) GET CURRENT DEFAULT DRIVE
				   ;OUTPUT: AL = CURRENT DRIVE
				   ;  0=A,1=B,ETC.
      CMP  AL,START_DR_NUM	   ;AN000;HAS THE ORIGINAL DOS DEFAULT DRIVE CHANGED?
      CLC			   ;AN000;NO ERROR
;     $IF  E			   ;AN000;IF NO CHANGE, THEN USER SPECIFIED
      JNE $$IF19
$$LL19:
				   ; INVALID DRIVE
	  MOV  MSGNUM_EXTERR,INVDRSPEC ;AN000;"INVALID DRIVE SPECIFICATION"
	  MOV  DI,OFFSET MSGNUM_EXTERR ;AN000;
	  CALL SENDMSG		   ;AN000;TELL USER HE SAID BAD DRIVE LETTER

	  STC			   ;AN000;RETURN AN ERROR
;     $ENDIF			   ;AN000;NO CHANGE?
$$IF19:
; $ELSE 			   ;AN000;SINCE DRIVE SPECIFIED IS THE SAME
  JMP SHORT $$EN18
$$IF18:
      CLC			   ;AN000;NO ERROR
; $ENDIF			   ;AN000;NEW DRIVE SPECIFIED?
$$EN18:
  RET				   ;AN000;RETURN TO CALLER
VERIFY_DRIVE ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <INIT_CONDITIONS - GET INITIAL SUBDIR, APPEND,CTL_BREAK> ;AN000;
INIT_CONDITIONS PROC NEAR	   ;AN000;
  PUBLIC INIT_CONDITIONS	   ;AN000; MAKE ENTRY IN LINK MAP
;INPUT	- "START_DR_NUM" WILL HAVE THE NUMERIC VALUE OF DOS DEFAULT DRIVE.
;	- "DEFAULT_DR" WILL HAVE THE LETTER DRIVE ID OF DOS DEFAULT DRIVE.
;OUTPUT - "APPEND_FLAGS" RECORDS ORIGINAL STATUS OF /X OF APPEND.
;		APPEND IS COMMANDED TO HALT ITS /X PROCESSING.
;	  CONTROL BREAK VECTOR IS ALTERED TO POINT TO MY HANDLER.
; =  =	=  =  =  =  =  =  =  =	=  =
;		SET UP THE LOCAL DTA
  MOV  DX,OFFSET FIX_DTA_RES	   ;AN000;PASS POINTER TO DTA BUFFER
  DOSCALL SET_DTA		   ;AN000;(1AH) SET DTA FOR FIND FIRST/NEXT
;		GET CURRENT APPEND STATUS
  MOV  AX,APPEND_CHECK		   ;AN006;SEE IF APPEND IS ACTIVE
  INT  2FH			   ;AN006;CALL THE MULTIPLEXOR FUNCTION

  OR   AL,AL			   ;AN006;TEST THE RESULTS
; $IF  NZ,AND			   ;AN006;IF INSTALLED
  JZ $$IF23

  MOV  AX,APPEND_VERSION	   ;AN006;ASK IF DOS VERSION OF APPEND
  INT  2FH			   ;AN006;CALL THE MULTIPLEXOR FUNCTION
  CMP  AX,DOS_APPEND_VER	   ;AN006;IS THIS THE DOS VERSION OF APPEND
; $IF  E			   ;AN006;YES, DEAL WITH THIS VERSION
  JNE $$IF23
      OR   FLAGS,F_APPEND	   ;AN000;FLAG IT AS THE DOS VERSION
      MOV  AX,GET_APPEND	   ;AN000;
      INT  2FH			   ;AN000;READ STATUS OF /X FROM APPEND
				   ;OUTPUT-BX=(SEE "APPEND_FLAGS" FOR DEFINITION
      MOV  APPEND_FLAGS,BX	   ;AC006;REMEMBER APPEND STATUS
; $ENDIF			   ;AN000;APPEND INSTALLED?
$$IF23:


;		CAPTURE THE CRITICAL ERROR VECTOR
  PUSH ES			   ;AN000;SAVE SEGREG
				   ;AL = INTERRUPT NUMBER
  DOSCALL GET_VECTOR,VEC_CRITERR   ;AN000;(3524H) GET INTERRUPT VECTOR
				   ;OUTPUT: ES:BX = CONTENTS OF VECTOR
  MOV  WORD PTR OLDINT24,BX	   ;AN000;SAVE THE ORIGINAL
  MOV  WORD PTR OLDINT24+WORD,ES   ;AN000; CRITICAL ERROR HANDLER VECTOR
  POP  ES			   ;AN000;RESTORE SEGREG

  MOV  DX,OFFSET MYERRORHANDLER    ;AN000;DS:DX = VECTOR TO INT HANDLER
				   ;AL = INTERRUPT NUMBER
  DOSCALL SET_VECTOR,VEC_CRITERR   ;AN000;(25H) SET INTERRUPT VECTOR

;		CAPTURE THE CONTROL BREAK VECTOR
  PUSH ES			   ;AN000;SAVE SEGREG
				   ;AL = INTERRUPT NUMBER
  DOSCALL GET_VECTOR,VEC_CTLBREAK  ;AN000;(3523H) GET INTERRUPT VECTOR
				   ;OUTPUT: ES:BX = CONTENTS OF VECTOR
  MOV  WORD PTR OLDINT23,BX	   ;AN000;SAVE THE ORIGINAL
  MOV  WORD PTR OLDINT23+WORD,ES   ;AN000; CTRL-BREAK VECTOR
  POP  ES			   ;AN000;RESTORE SEGREG

  MOV  DX,OFFSET BREAK_HANDLER	   ;AN000;DS:DX = VECTOR TO INT HANDLER
				   ;AL = INTERRUPT NUMBER
  DOSCALL SET_VECTOR,VEC_CTLBREAK  ;AN000;(25H) SET INTERRUPT VECTOR

;		STOP THE APPEND FUNCTION.
  MOV  AX,SET_APPEND		   ;AN000;CHANGE APPEND /X STATUS
  XOR  BX,BX			   ;AN000;REQUEST TERMINATION OF /X SUPPORT OF APPEND
  INT  2FH			   ;AN000;SET IT

  RET				   ;AN000;RETURN TO CALLER
INIT_CONDITIONS ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <GET_VOL_LABEL - GET VOLUME LABEL ON SPECIFIED DRIVE> ;AN000;
GET_VOL_LABEL PROC NEAR 	   ;AN000;
  PUBLIC GET_VOL_LABEL		   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT - "START_PATH" IS ASCIIZ OF STARTING PATH
;OUTPUT - "FIX_DTA_FILN" WILL HAVE ASCIIZ STRING OF VOLUMN LABEL.
;	  STARTING DRIVE AND PATH TO SPECIFIED SUBDIR IS DISPLAYED.
; =  =	=  =  =  =  =  =  =  =	=  =

  MOV  CX,ATTR_VOLID		   ;AN000;REQUEST THE VOLUME ID
  MOV  DX,OFFSET STAR_STAR	   ;AN000;PASS FILENAME TO BE LOOKED FOR
  DOSCALL FINDFIRST		   ;AN000;LOOK FOR VOLUME LABEL

; $IF  NC			   ;AN000;IF LABEL FOUND OK,
  JC $$IF25

				   ;FIX_DTA_FILN HAS VOLUME LABEL
      MOV  DI,OFFSET MSGNUM_VOL    ;AN000; "Directory PATH listing for Volume %1"
      MOV  AX,WORD PTR FIX_DTA_FILN+9 ;AN005;CONVERT LABELNAME FROM
      MOV  WORD PTR FIX_DTA_FILN+8,AX ;AN005;	12345678.123 FORMAT
      MOV  AX,WORD PTR FIX_DTA_FILN+11 ;AN005;	TO REMOVE PERIOD
      MOV  WORD PTR FIX_DTA_FILN+10,AX ;AN005;	TO BECOME 12345678123 INSTEAD
; $ELSE 			   ;AN000;SINCE LABEL NOT FOUND,
  JMP SHORT $$EN25
$$IF25:
      MOV  DI,OFFSET MSGNUM_LIST   ;AN000; "Directory PATH listing"
; $ENDIF			   ;AN000;LABEL FOUND?
$$EN25:
  CALL SENDMSG			   ;AN000;DISPLAY STARTING MESSAGE

  CALL VOLSER			   ;AN001;DISPLAY VOLUME SERIAL NUMBER, IF ANY


;		DISPLAY THE STARTING DRIVE AND SUBDIRECTORY
  MOV  DX,OFFSET START_DRIVE	   ;AN000;PASS POINTER TO STRING TO BE DISPLAYED
  CALL LEN_ASCIIZ		   ;AN000;SETS CX = NUMBER OF BYTES TO WRITE

				   ;DS:DX = ADDRESS OF DATA TO WRITE
  CALL DO_WRITE 		   ;AN000;DISPLAY STARTING SUBDIR TO STDOUT

  RET				   ;AN000;RETURN TO CALLER
GET_VOL_LABEL ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <VOLSER - DISPLAY VOLUME SERIAL NUMBER, IF ANY> ;AN001;
VOLSER PROC NEAR		   ;AN001;
  PUBLIC VOLSER 		   ;AN001;
;IF THE MEDIA SUPPORTS A VOL SERIAL NUMBER, DISPLAY IT
; =  =	=  =  =  =  =  =  =  =	=  =
;	       ISSUE GET MEDIA ID
  MOV  BH,ZERO			   ;AN001;BH=0, RES
  MOV  BL,START_DRIVE		   ;AN001;GET LETTER OF DRIVE BEING LOOKED AT
  SUB  BL,DRIVEA-1		   ;AN001;(BACK UP 40H) BL=DRIVE NUM (1=A:, 2=B:, ETC)
  MOV  DX,OFFSET MEDIA_ID_BUF	   ;AN001;DS:DX=BUFFER (see A_MEDIA_ID_INFO STRUC)
  DOSCALL GSET_MEDIA_ID,GET_ID	   ;AC010;(6900H) GET MEDIA ID
				   ;CARRY SET ON ERROR (OLD STYLE BOOT RECORD)

; $IF  NC			   ;AN001;IF THE GET MEDIA ID WORKED OK,
  JC $$IF28

; NOTE: IN THE FOLLOWING TWO SUBLISTS, WE ARE GOING TO DISPLAY, IN HEX,
; A CONSECUTIVE SET OF 4 BYTES, THE VOLUME SERIAL NUMBER.  THE ORDER OF
; THESE TWO WORDS OF HEX IS, LEAST SIGNIFICANT WORD FIRST, THEN THE
; MOST SIGNIFICANT WORD.  WHEN DISPLAYED, THE MOST SIGNIFICANT IS TO BE
; DISPLAYED FIRST, SO THE VALUE AT SERIAL+2 GOES TO THE 6A SUBLIST,
; AND THE LEAST SIGNIFICANT VALUE AT SERIAL+0 GOES TO THE SECOND POSITION,
; REPRESENTED BY THE 6B SUBLIST.

      LEA  AX,MEDIA_ID_BUF.MI_SERIAL ;AN001;GET POINTER TO DATA TO BE PRINTED
      MOV  SUBLIST_6B.SUB_VALUE,AX ;AN001; INTO THE SUBLIST FOR %2

      LEA  AX,MEDIA_ID_BUF.MI_SERIAL+WORD ;AN001;GET POINTER TO DATA TO BE PRINTED
      MOV  SUBLIST_6A.SUB_VALUE,AX ;AN001; INTO THE SUBLIST FOR %1

				   ;"Volume Serial Number is %1-%2"
      MOV  DI,OFFSET MSGNUM_SERNO  ;AN001;DISPLAY THE NEW SERIAL NUMBER
      CALL SENDMSG		   ;AN001;DISPLAY THE MESSAGE

; $ENDIF			   ;AN001;IS VOL SERIAL NUM PRESENT?
$$IF28:
  RET				   ;AN001;RETURN TO CALLER
VOLSER ENDP			   ;AN001;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <LEN_ASCIIZ - GET LENGTH OF ASCIIZ STRING> ;AN000;
LEN_ASCIIZ PROC NEAR		   ;AN000;
  PUBLIC LEN_ASCIIZ		   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT - ES:DX = POINTS TO START OF ASCIIZ STRING
;OUTPUT - CX = LENGTH OF CHARACTERS, INCLUDING THE NUL AT THE END
; =  =	=  =  =  =  =  =  =  =	=  =

  PUSH AX			   ;AN000;SAVE THE CALLER'S
  PUSH DI			   ;AN000; REGISTERS
  MOV  CX,FULL_SEG_SIZE 	   ;AN000;BETTER FIND THAT NUL SOMEWHERE...
  MOV  DI,DX			   ;AN000;SET INDEX TO WALK THRU THE STRING
  MOV  AL,NUL			   ;AN000;THIS IS THE CHAR I AM LOOKING FOR
  REPNE SCASB			   ;AN000;LOOK FOR IT

  SUB  DI,DX			   ;AN000;TAKE AWAY WHERE WE STARTED, FROM WHERE WE AT
  MOV  CX,DI			   ;AN000; TO FIND NOW FAR WE MOVED
  POP  DI			   ;AN000;RESTORE THE CALLER'S
  POP  AX			   ;AN000; REGISTERS

  RET				   ;AN000;RETURN TO CALLER
LEN_ASCIIZ ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <EXECUTE - LOOK THRU DIRECTORY LIST FOR SUBDIRS> ;AN000;
EXECUTE PROC NEAR		   ;AN000;
  PUBLIC EXECUTE		   ;AN000;MAKE ENTRY IN LINK MAP
;BECAUSE OF THE RECURSIVE NATURE OF THIS ROUTINE, ALL ITS LOCAL WORKAREA
;MUST BE DYNAMICALLY ALLOCATED BY USING A PORTION OF THE STACK.  AS EACH
;LOWER LEVEL OF STACK IS PROCESSED, A NEW CALL IS MADE TO THIS SUBROUTINE
;WHICH THEN CREATES A NEW WORKAREA FOR THAT SUBDIRECTORY.
;THE CURRENT STACK SIZE IS CHECKED TO SEE IF THERE IS ENOUGH ROOM FOR
;THE NEW STACK WORKAREA.
;INPUT:START_PATH - STRING OF PATHNAME OF PATH TO BE PROCESSED
;OUTPUT: WHEN THIS PROC RETURNS, ALL FILES IN THIS SUBDIR AND LOWER
;	LEVELS OF SUBDIRS HAVE BEEN PROCESSED.
; =  =	=  =  =  =  =  =  =  =	=  =

  PUSH BP			   ;AN000;SAVE CALLER'S BP REG
  SUB  SP,WA_SIZE		   ;AN000;ALLOCATE STACK SPACE AS WORKAREA
  MOV  BP,SP			   ;AN000;SET BASE FOR WORKAREA CALLED "FRAME"

  MOV  AX,BP			   ;AN000;
  SUB  AX,OFFSET LAST_BYTE	   ;AN000;WHERE MY CODE ENDS
  CMP  AX,MIN_STACK		   ;AN000;IS THE MINIMUM STACK REMAINING?
; $IF  AE			   ;AN000;IF ENUF STILL THERE, CONTINUE,
  JNAE $$IF30

      CMP  START_PATH,BACK_SLASH   ;AN000;WAS A BACKSLASH SDIR SPECIFIED,
;     $IF  NE			   ;AN000;NO BACKSLASH USED
      JE $$IF31
	  MOV  DX,OFFSET START_PATH ;AN000;POINT TO SPECIFIED PATH
	  DOSCALL CHDIR 	   ;AN000;(3BH) CHANGE CURRENT DIR

;	  $IF  NC		   ;AN000;IF CHDIR WORKED OK,
	  JC $$IF32
	      MOV  DL,START_DRIVE  ;AN000;GET TARGET DRIVE
	      SUB  DL,DRIVEA-1	;AN000;CONVERT TO NUM (A=1,B=2,ETC.)
	      LEA  SI,[BP].FRAM_CURR_PATH+1 ;AN000;WHERE TO PUT PATH
	      MOV  [BP].FRAM_CURR_PATH,BACK_SLASH ;AN000;
	      DOSCALL GET_CUR_DIR  ;AN000;FIND WHERE WE ARE NOW

	      LEA  SI,[BP].FRAM_CURR_PATH ;AN000;WHERE PATH WENT, WITH BACKSLASH
	      MOV  DI,OFFSET START_PATH ;AN000;WHERE TO PUT IT
	      MOV  CX,MAX_PATH+1 ;AN000;MOVE FULL LENGTH PLUS BACKSLASH
	      REP  MOVSB	   ;AN000; TO START_PATH

;	  $ENDIF		   ;AN000;CHDIR OK?
$$IF32:

;     $ELSE			   ;AN000;SINCE SPECIFIED PATH STARTS WITH BACKSLASH
      JMP SHORT $$EN31
$$IF31:
	  MOV  SI,OFFSET START_PATH ;AN000;USING THE STARTING PATH,
	  LEA  DI,[BP].FRAM_CURR_PATH ;AN000;SAVE IT IN THE STACK WORKAREA
				   ;(at times like this, sure is nice to
				   ; have ES=SS.  .EXE would be a problem..)
	  MOV  CX,MAX_PATH+1	;AN000;MOVE THE ENTIRE STARTING PATH+LEADING "\"
	  REP  MOVSB		   ;AN000;INTO THE WORKAREA

	  MOV  DX,OFFSET START_PATH ;AN000;POINT TO SPECIFIED PATH
	  DOSCALL CHDIR 	   ;AN000;(3BH) CHANGE CURRENT SDIR TO SPECIFIED SDIR

;     $ENDIF			   ;AN000;PERIOD SDIR SPECIFIED?
$$EN31:

;     $IF  NC			   ;AN000;IF CHDIR WORKED OK,
      JC $$IF36
	  CALL ANY_MORE_SUBDIR	   ;AN000;SEE IF MORE SUBDIRS BELOW THIS ONE
				   ;SETS "FRAM_CHAR" TO:
				   ;  "ELBO" - NO MORE DIR BELOW THIS ONE
				   ;  "TEE" - THERE IS ANOTHER DIR BELOW HERE
	  TEST FLAGS,F_SWITCH	   ;AN000;ARE ALL FILES ASKED FOR?
				   ; (TEST WILL CLEAR CARRY FLAG)
;	  $IF  NZ		   ;AN000;IS /F SET?
	  JZ $$IF37
	      CALL FIND_TYPE_NORMAL ;AN000;DISPLAY ALL THE FILENAMES

;	  $ENDIF		   ;AN000;/F?
$$IF37:
	  CALL FIND_TYPE_DIR	   ;AN000;DISPLAY ALL THE DIRECTORIES

;     $ELSE			   ;AN000;SINCE CHDIR FAILED
      JMP SHORT $$EN36
$$IF36:
	  MOV  DI,OFFSET MSGNUM_INVPATH ;AN000;"INVALID PATH"
	  CALL SENDMSG		   ;AN000;SAY WHY I QUIT

	  MOV  EXITFL,EXERR	   ;AN000;SET ERROR FLAG TO QUIT
;     $ENDIF			   ;AN000;CHDIR OK?
$$EN36:
				   ;FINISHED WITH THIS SUBDIRECTORY, SO
; $ELSE 			   ;AN000;SINCE STACK TOO SMALL
  JMP SHORT $$EN30
$$IF30:
      MOV  DI,OFFSET MSGNUM_EXTERR ;AN000;DESCRIPTOR FOR EXTENDED ERRORS
      MOV  [DI].MSG_NUM,INSUF_MEM  ;AN000;"INSUFFICIENT MEMORY"
      CALL SENDMSG		   ;AN000;

      MOV  EXITFL,EXERR 	   ;AN000;SET ERRORLEVEL RET CODE
; $ENDIF			   ;AN000;
$$EN30:
  ADD  SP,WA_SIZE		   ;AN000;DISCARD WORKAREA
  POP  BP			   ;AN000;RESTORE CALLER'S BP REG
  RET				   ;AN000;RETURN TO CALLER
EXECUTE ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <ANY_MORE_SUBDIR - LOOK AHEAD,SEE IF MORE SUBDIR> ;AN000;
ANY_MORE_SUBDIR PROC		   ;AN000;
;HAVING JUST DONE A FIND FIRST/NEXT FOR A SUBDIRECTORY,LOOK FOR ANOTHER
;INPUT: BP=DYNAMIC WORKAREA
;	"FLAGS" FIRST TIME SWITCH
;	FOR FIRST TIME, "START_DRIVE" AND "START_PATH" SET WITH WHERE TO LOOK.
;	FIX_DTA_FILN MAY HAVE LATEST FILE PROCESSED, OR NOTHING
;OUTPUT:"FRAM_CHAR"="ELBO" = NO MORE SUBDIRS AFTER THIS ONE.
;	"FRAM_CHAR"="TEE"  = ANOTHER SUBDIR AFTER THIS ONE
;	"EXITFL" SET TO NON ZERO IF REAL ERROR OCCURRED.
;	FIX_DTA_FILN IS RESTORED TO WHATEVER IT HAD.
; =  =	=  =  =  =  =  =  =  =	=  =
  MOV  SI,OFFSET FIX_DTA_FILN	   ;AN000;FROM THE DTA, FILENAME AREA
  MOV  DI,OFFSET SAVEFILN	   ;AN000; TO A TEMPORARY LOCATION
  MOV  CX,LENGTH SAVEFILN	   ;AN000; SAVE THE ENTIRE FILENAME FIELD
  REP  MOVSB			   ;AN000; INTO THE TEMPORARY LOCATION

  TEST FLAGS,F_FIRSTIME 	   ;AN000;IS THIS THE FIRST TIME?
; $IF  Z			   ;AN000;IF THE FIRST TIME
  JNZ $$IF43
      MOV  CX,ATTR_DIR		   ;AN000;SET ATTRIBUTE TO SUBDIR
      MOV  DX,OFFSET STAR_STAR	   ;AN000;PASS FILENAME TO BE LOOKED FOR
      DOSCALL FINDFIRST 	   ;AN000;

; $ELSE 			   ;AN000;SINCE NOT FIRST TIME
  JMP SHORT $$EN43
$$IF43:
      DOSCALL FINDNEXT		   ;AN000;LOOK FOR ANOTHER SUBDIR

; $ENDIF			   ;AN000;FIRSTIME?
$$EN43:
; $SEARCH COMPLEX		   ;AN000;
  JMP SHORT $$SS46
$$DO46:
      DOSCALL FINDNEXT		   ;AN000;LOOK FOR ANOTHER SUBDIR
; $STRTSRCH			   ;AN000;
$$SS46:
; $EXITIF C			   ;AN000;IF ERROR WITH FINDNEXT
  JNC $$IF46
      CALL IF_NOMOREFILES	   ;AN000;SEE IF REASON FOR ERROR IS NO MORE FILES
				   ;CY NOT SET = "NO MORE FILES"
				   ;CY IS SET = OTHER PROBLEM, "EXITFL" SET
      MOV  AL,GRAF_ELBO 	   ;AN002;CHANGE TO ELBO
      MOV  [BP].FRAM_CHAR,AL	   ;AC002;SAY NO MORE SUBDIR
; $ORELSE			   ;AN000;SINCE NO ERROR WITH FINDNEXT
  JMP SHORT $$SR46
$$IF46:
      CMP  FIX_DTA_ATTR,ATTR_DIR   ;AN000;DID I FIND A SUBDIR?
; $ENDLOOP E,AND		   ;AN000;FINDNEXT OK?
  JNE $$DO46
      CMP  FIX_DTA_FILN,PERIOD	   ;AN000;IS THIS FILENAME STARTING WITH "PERIOD"?
; $ENDLOOP NE			   ;AN000;IF NOT, FOUND A REAL SUBDIR
  JE $$DO46
      MOV  AL,GRAF_TEE		   ;AN002;CHANGE TO TEE
      MOV  [BP].FRAM_CHAR,AL	   ;AN002;SAY STILL MORE SUBDIR
; $ENDSRCH			   ;AN000;
$$SR46:

  TEST FLAGS,F_FIRSTIME 	   ;AN000;IS THIS THE FIRST TIME?
; $IF  NZ			   ;AN000;IF NOT THE FIRST TIME
  JZ $$IF52
      MOV  DI,OFFSET FIX_DTA_RES   ;AN000;MOVE TO THE FIXED DTA AREA
      LEA  SI,[BP].FRAM_DTA_RES    ;AN000; FROM DYNAMIC AREA IN STACK
      MOV  CX,LENGTH FIX_DTA_RES   ;AN000;SET COUNT TO FIELD SIZE
      REP  MOVSB		   ;AN000;SAVE THIS IN DYNAMIC WORKAREA STACK

; $ENDIF			   ;AN000;
$$IF52:
  MOV  DI,OFFSET FIX_DTA_FILN	   ;AN000;FROM A TEMPORARY LOCATION
  MOV  SI,OFFSET SAVEFILN	   ;AN000; TO THE DTA, FILENAME AREA
  MOV  CX,LENGTH SAVEFILN	   ;AN000; RESTORE THE ENTIRE FILENAME FIELD
  REP  MOVSB			   ;AN000; FROM THE TEMPORARY LOCATION

  RET				   ;AN000;RETURN TO CALLER
ANY_MORE_SUBDIR ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <FIND_TYPE_NORMAL - PROCESS NORMAL, NON-DIR, FILES> ;AN000;
FIND_TYPE_NORMAL PROC NEAR	   ;AN000;
  PUBLIC FIND_TYPE_NORMAL	   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT - PB=BASE OF FRAME, DYNAMIC WORKAREA WITH DTA
;OUTPUT - CY SET IF A PROBLEM, AND "EXITFL" HAS ERROR CODE
;	  CY CLEAR IF NORMAL "NO MORE FILES" FROM FIND FIRST/NEXT.
; =  =	=  =  =  =  =  =  =  =	=  =

  AND  FLAGS,0FFH-F_FLN 	   ;AN000;CLEAR INDICATOR FOR THIS SUBDIR
				   ;  TO SAY NO FILES PRINTED YET FOR THIS SDIR ;AN000;
  MOV  CX,ATTR_NORMAL		   ;AN000;SET TO LOOK FOR ALL FILES
  CALL BEGIN_FIND		   ;AN000;DO FIND FIRST

; $DO				   ;AN000;STEP THRU EACH ENTRY IN THIS SUBDIR
$$DO54:
; $LEAVE C			   ;AN000;QUIT IF ERROR
  JC $$EN54
      OR   FLAGS,F_FLN		   ;AN000;REQUEST THIS PRINTOUT BE DONE
      CALL SHOW_FN		   ;AN000;SHOW THIS FILE JUST FOUND

      CALL FIND_NEXT		   ;AN000;LOOK FOR ANOTHER

; $ENDDO			   ;AN000;LEAVE WILL QUIT IF PROBLEM WITH FINDNEXT
  JMP SHORT $$DO54
$$EN54:
  CALL IF_NOMOREFILES		   ;AN000;SEE IF REASON FOR ERROR IS NO MORE FILES
				   ;CY NOT SET = "NO MORE FILES"
				   ;CY IS SET = OTHER PROBLEM, "EXITFL" SET
; $IF  NC			   ;AN000;IF NO MORE FILES,
  JC $$IF57
      MOV  AL,BLANK		   ;AN000;
      MOV  DI,OFFSET FIX_DTA_FILN  ;AN000;WHERE NAME IS TO GO
      MOV  CX,LENGTH FIX_DTA_FILN  ;AN000;NO. BYTES IN FILENAME FIELD
      REP  STOSB		   ;AN000;FILL FILENAME FIELD WITH BLANKS

      MOV  AL,ATTR_NORMAL	   ;AN000;SAY IT IS JUST A FILENAME
      CALL SHOW_FN		   ;AN000;OUTPUT A BLANK LINE

; $ENDIF			   ;AN000;NO MORE FILES?
$$IF57:

  RET				   ;AN000;RETURN TO CALLER
FIND_TYPE_NORMAL ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <FIND_TYPE_DIR - PROCESS THE DIRECTORY> ;AN000;
FIND_TYPE_DIR PROC NEAR 	   ;AN000;
  PUBLIC FIND_TYPE_DIR		   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT - PB=BASE OF FRAME, DYNAMIC WORKAREA WITH DTA
;OUTPUT - CY SET IF A PROBLEM
;	  CY CLEAR IF NORMAL "NO MORE FILES" FROM FIND FIRST/NEXT.
; =  =	=  =  =  =  =  =  =  =	=  =
  OR   FLAGS,F_FLN		   ;AN000;PERMIT DISPLAY OF BUFFER
  MOV  CX,ATTR_DIR		   ;AN000;LOOK FOR DIRECTORY ATTRIBUTE
  CALL BEGIN_FIND		   ;AN000;DO FIND FIRST

; $SEARCH			   ;AN000;STEP THRU EACH ENTRY IN THIS SUBDIR
$$DO59:
; $LEAVE C			   ;AN000;QUIT IF ERROR
  JC $$EN59
      CMP  FIX_DTA_FILN,PERIOD	   ;AN000;WAS THAT A "PERIOD" FILENAME?
;     $IF  NE			   ;AN000;IF NOT, GO CHECK IT OUT
      JE $$IF61
	  MOV  AL,FIX_DTA_ATTR	   ;AN000;LOOK AT ATTRIB OF THIS FILE
	  CMP  AL,ATTR_DIR	   ;AN000;IS THIS A DIRECTORY?
;	  $IF  E		   ;AN000;IF DIR,
	  JNE $$IF62
	      CALL SHOW_FN	   ;AN000;SHOW THIS FILE JUST FOUND

	      ADD  CURRENT_COL,DASH_NUM+1 ;AN000;LOCATE SDIR NAME IN PRINTOUT LINE
	      MOV  SI,CURRENT_COL  ;AN000;
	      LEA  SI,BUF-1[SI] ;AN000;POINT AT SUBDIR NAME JUST PRINTED
	      MOV  DI,OFFSET FIX_DTA_FILN ;AN000;WHERE "NEXT_LEVEL" EXPECTS IT
	      MOV  CX,LENGTH FIX_DTA_FILN ;AN000;
	      REP  MOVSB	   ;AN000;SET UP SUBDIR NAME TO GO PROCESS

	      CALL NEXT_LEVEL	   ;AN000;SHIFT TO LOWER LEVEL SUBDIRECTORY

	      CALL EXECUTE	   ;AN000;RECURSIVE CALL, PROCESS NEW LEVEL OF SUBDIR

	      SUB  CURRENT_COL,DASH_NUM+1 ;AN000;BACK TO ORIGINAL LEVEL
	      LEA  DX,[BP].FRAM_CURR_PATH ;AN000;DS:DX = POINTER TO ASCIIZ STRING
	      DOSCALL CHDIR	   ;AN000;(3BH) CHANGE CURRENT DIRECTORY
				   ;GO BACK TO THE DIRECTORY THIS LEVEL OF
				   ; STACK WORKAREA HAS BEEN DEALING WITH,
				   ; SINCE "EXECUTE" HAD CHANGED IT TO WORK ON
				   ; A LOWER SUBDIRECTORY.
;	  $ENDIF		   ;AN000;DIR?
$$IF62:
;     $ENDIF			   ;AN000;"PERIOD" FILENAME?
$$IF61:
      CMP  EXITFL,EXOK		   ;AN000;ANY ERRORS SO FAR?
; $EXITIF NE,NUL		   ;AN000;YES, QUIT THIS MESS; OTHERWISE KEEP LOOKING
  JNE $$SR59
      CALL FIND_NEXT		   ;AN000;LOOK FOR ANOTHER

; $ENDLOOP			   ;AN000;LEAVE WILL QUIT IF PROBLEM WITH FINDNEXT
  JMP SHORT $$DO59
$$EN59:
      CMP  EXITFL,EXOK		   ;AN000;IF NO ERROR FOUND SO FAR
;     $IF  E			   ;AN000;
      JNE $$IF67
	  CALL IF_NOMOREFILES	   ;AN000;SEE IF REASON FOR ERROR IS NO MORE FILES
				   ;CY NOT SET = "NO MORE FILES"
				   ;CY IS SET = OTHER PROBLEM, "EXITFL" SET
;     $ENDIF			   ;AN000;ANY ERRORS SO FAR?
$$IF67:
; $ENDSRCH			   ;AN000;
$$SR59:
  RET				   ;AN000;RETURN TO CALLER
FIND_TYPE_DIR ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <NEXT_LEVEL - SET UP TO LOOK AT LOWER LEVEL SUBDIR> ;AN000;
NEXT_LEVEL PROC NEAR		   ;AN000;
  PUBLIC NEXT_LEVEL		   ;AN000;
;INPUT: FIX_DTA_FILN - FILE NAME OF LOWER LEVEL SUBDIR
;OUTPUT: START_PATH - HAS COMPLETE PATH TO THE NEW LEVEL SUBDIR
; =  =	=  =  =  =  =  =  =  =	=  =

  MOV  SI,OFFSET START_PATH+1	;AN000;WHERE TO SAVE CURRENT PATH
  MOV  DL,DEFDRIVE		   ;AN000;DL = DRIVE NUM (0=DEF, 1=A, ETC)
  DOSCALL GET_CUR_DIR		   ;AN000;(47H) GET CURRENT DIRECTORY
				   ;OUTPUT: DS:SI POINTS TO FULL PATH NAME
  DEC  SI			   ;AN012;START SCAN AT START_PATH
  CALL SCAN_DBCS		   ;AN012;GET LAST 2 CHARS IN DL,DH
				   ; SI NOW AT END OF STRING
  MOV  DI,SI			   ;AN012;GET POINTER TO NUL
  CMP  DL,BACK_SLASH		   ;AN000;
; $IF  NE			   ;AN012;IF PATH NOT ALREADY TERMINATED WITH A "\"
  JE $$IF70
      MOV  BYTE PTR [DI],BACK_SLASH ;AN000;TERMINATE PREVIOUS PATH
      INC  DI			   ;AN000;DI POINTS TO NEXT NUL AT END OF STRING
; $ENDIF			   ;AN000;END IN "\"?
$$IF70:
  MOV  SI,OFFSET FIX_DTA_FILN	   ;AN000;GET NAME OF NEW SUBDIR
  MOV  CX,LENGTH FIX_DTA_FILN	   ;AN000;
  REP  MOVSB			   ;AN000;ADD THE NEW SUBDIR TO END

  AND  FLAGS,0FFH - F_FIRSTIME	   ;AN000;IN NEW SUBDIR, REQUEST FIND FIRST TO START
  RET				   ;AN000;RETURN TO CALLER
NEXT_LEVEL ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <SCAN_DBCS - FIND LAST 2 SBCS CHARS IN ASCIIZ> ;AN000;
SCAN_DBCS PROC NEAR		   ;AN000;
  PUBLIC SCAN_DBCS		   ;AN000;
;INPUT: DS:SI = ASCIIZ STRING TO BE SCANNED
;OUTPUT: DL=LAST SBCS CHAR BEFORE NUL
;	 DH=NEXT TO LAST SBCS CHAR BEFORE NUL
;	 IF NO SBCS CHAR FOUND, DL OR DH WILL BE NUL
;	 SI=OFFSET TO NUL DELIMITER

  XOR  DX,DX			   ;AN000;CLEAR CHAR ACCUMULATOR
; $DO				   ;AN000;
$$DO72:
      LODSB			   ;AN000;GET NEXT CHAR FROM DS:SI TO AL
      CMP  AL,NUL		   ;AN000;IS THAT THE DELIMITER?
; $LEAVE E			   ;AN000;FOUND THE END, SO QUIT
  JE $$EN72
      CALL CHK_DBCS		   ;AN000;IS THIS THE FIRST OF A DBCS PAIR?

;     $IF  C			   ;AN000;IF SO, FOUND A DBCS PAIR
      JNC $$IF74
	  INC  SI		   ;AN000;SKIP ITS PARTNER
	  MOV  AL,NUL		   ;AN000;PASS BACK A NUL, INSTEAD OF AN SBCS CHAR
;     $ENDIF			   ;AN000;
$$IF74:
      MOV  DH,DL		   ;AN000;SAVE PREVIOUS CHAR
      MOV  DL,AL		   ;AN000;REMEMBER THE CHAR JUST FOUND
; $ENDDO			   ;AN000;
  JMP SHORT $$DO72
$$EN72:
  DEC  SI			   ;AN000;LODSB SET SI ONE BEYOND NUL
				   ; SO SET SI BACK TO POINT TO THE NUL
  RET				   ;AN000;RETURN TO CALLER
SCAN_DBCS ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <BEGIN_FIND - DO FIND FIRST FILE> ;AN000;
BEGIN_FIND PROC NEAR		   ;AN000;
  PUBLIC BEGIN_FIND		   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT- CURRENT DOS DEFAULT DRIVE HAS TARGET DRIVE TO BE RESEARCHED.
;	CURRENT DEFAULT SUBDIRECTORY HAS SUBDIR TO BE RESEARCHED.
;	CX = ATTRIBUTE OF FILE TYPE TO LOOK FOR
;	BP = OFFSET OF DYNAMIC WORKAREA
;OUTPUT - DTA IS SET UP WITH FIRST FILE FOUND, READY TO BE USED BY FIND NEXT.
;	WORKAREA HAS SAVED THE RESULT OF FINDFIRST.
; =  =	=  =  =  =  =  =  =  =	=  =

  MOV  DX,OFFSET STAR_STAR	   ;AN000;PASS FILENAME TO BE LOOKED FOR
  DOSCALL FINDFIRST		   ;AN000;(4EH) LOOK FOR FIRST SUBDIRECTORY

  MOV  SI,OFFSET FIX_DTA_RES	   ;AN000;MOVE FROM THE FIXED DTA AREA
  LEA  DI,[BP].FRAM_DTA_RES	   ;AN000; TO THE DYNAMIC AREA IN STACK
  MOV  CX,LENGTH FIX_DTA_RES	   ;AN000;SET COUNT TO FIELD SIZE
  REP  MOVSB			   ;AN000;SAVE THIS IN DYNAMIC WORKAREA STACK

  RET				   ;AN000;RETURN TO CALLER
BEGIN_FIND ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <FIND_NEXT - LOOK FOR NEXT ENTRY IN DIRECTORY> ;AN000;
FIND_NEXT PROC NEAR		   ;AN000;
  PUBLIC FIND_NEXT		   ;AN000;
;INPUT: RESERVED FIELD, LEFT FROM PREVIOUS FIND FIRST/NEXT, IN [BP].FRAM_DTA_RES
;OUTPUT: [BP].FRAM_DTA_RES UPDATED WITH NEW RESERVED DATA, FROM CURRENT DTA
;	FIX_DTA.? FIELDS ARE SET UP TO DEFINE NEW FILE JUST FOUND.
;	CY SET IF NO MORE FILES FOUND, CY CLEAR IF A NEW FILE FOUND.
; =  =	=  =  =  =  =  =  =  =	=  =
  LEA  SI,[BP].FRAM_DTA_RES	   ;AN000;GET WHAT WAS LEFT FROM LAST FIND
  MOV  DI,OFFSET FIX_DTA_RES	   ;AN000;INTO THE FIXED DTA AREA
  MOV  CX,LENGTH FIX_DTA_RES	   ;AN000;SET COUNT TO FIELD SIZE
  REP  MOVSB			   ;AN000;SET UP DTA FOR FIND

  DOSCALL FINDNEXT		   ;AN000;(4FH) CARRY WILL BE SET TO REFLECT RESULT

  MOV  SI,OFFSET FIX_DTA_RES	   ;AN000;MOVE FROM THE FIXED DTA AREA
  LEA  DI,[BP].FRAM_DTA_RES	   ;AN000; TO THE DYNAMIC AREA IN STACK
  MOV  CX,LENGTH FIX_DTA_RES	   ;AN000;SET COUNT TO FIELD SIZE
  REP  MOVSB			   ;AN000;SAVE THIS IN DYNAMIC WORKAREA STACK

  RET				   ;AN000;RETURN TO CALLER
FIND_NEXT ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <SHOW_FN - DISPLAY THE FILENAME FOUND> ;AN000;
SHOW_FN PROC NEAR		   ;AN000;
  PUBLIC SHOW_FN		   ;AN000;MAKE ENTRY IN LINK MAP
;INPUT - BP=OFFSET TO WORKAREA IN STACK
;	 AL=ATTRIBUTE OF FILENAME AS DEFINED IN DIR ENTRY
;	 FLAGS (F_FLN) INDICATOR OF FLN HAVING BEEN PRINTED
;OUTPUT - "BUF" IS SET UP TO CONTAIN THE DISPLAY LINE, AND IS SENT TO STDOUT.
; =  =	=  =  =  =  =  =  =  =	=  =
;DESCRIPTION OF THE LINE TO BE DISPLAYED, IN "BUF":
;"CURRENT_COL" HAS COL NUMBER WHERE LEADING GRAPHIC IS TO GO.
;"DASH_NUM" IS THE NUM OF DASHES THAT IMMEDIATELY FOLLOWS THE LEADING
;   GRAPHIC.  (FOR SUBDIRECTORIES ONLY - FOR REGULAR FILENAMES, THIS
;   FIELD WOULD HAVE SPACES INSTEAD OF DASHES.)
;"FLN_INDENT" IS THE NUMBER OF SPACES TO BE PUT RIGHT IN FRONT OF A
;   FILENAME.  FOR SUBDIRS, THERE IS NO SUCH FIELD
;EXAMPLE, FOR SUBDIRS
;      ����DIR_FILN
;	  FOR ORDINARY FILES
;      �xxxssssANY_FILN.EXT  (WHERE x AND s ARE SPACES)
; =  =	=  =  =  =  =  =  =  =	=  =

  CMP  FIX_DTA_FILN,PERIOD	   ;AN000;DOES FILENAME START WITH PERIOD?
; $IF  NE			   ;AN000;IF NOT, CONTINUE...
  JE $$IF77
      MOV  BL,AL		   ;AN000;SAVE FILE ATTRIBUTE IN AL INTO BL

      CALL FLN_TO_BUF		   ;AN000; MOVE NAME OF FILE TO OUTPUT BUFFER

      CALL GRAF_TO_BUF		   ;AN000;DETERMINE LEADING GRAPHIC FOR BUFFER

      CALL BLANK_DASH		   ;AN000;PUT BLANKS OR DASHES INTO BUF BEFORE FILENAME

;		BUFFER INITIALIZED, DISPLAY IT

      MOV  DX,OFFSET BUF	   ;AN000;DISPLAY FILENAME OF FILE FOUND
      CALL LEN_ASCIIZ		   ;AN000;SET CX=LEN OF DX@ BUFFER, UP THRU NUL

      DEC  CX			   ;AN000;FORGET THE NUL
      TEST FLAGS,F_FLN		   ;AN000;HAVE ANY FLN BEEN PRINTED YET?
;     $IF  NZ			   ;AN000;IF SO, PRINT THIS
      JZ $$IF78
	  CALL DO_WRITE 	   ;AN000;DISPLAY FILENAME IN DX TO STDOUT

;     $ENDIF			   ;AN000;FILES PRINTED YET?
$$IF78:
;		CLEAN UP BUFFER FOR NEXT TIME

      CALL FIX_GRAF		   ;AN000;SET UP GRAPHIC FOR NEXT LINE

      MOV  AL,[BP].FRAM_CHAR	   ;AN000;GET ALTERED GRAPHIC CHAR
      MOV  DI,CURRENT_COL	   ;AN000;FIND WHERE IN "BUF"
      LEA  DI,BUF-1[DI]    ;AN000; TO PUT ALTERED GRAPHIC
      STOSB			   ;AN000;STORE ALTERED GRAPHIC INTO BUFFER

      CMP  BL,ATTR_DIR		   ;AN000;LOOK AT ATTRIB OF FILENAME
;     $IF  E			   ;AN000;IF IS A SUBDIRECTORY
      JNE $$IF80
	  OR   FLAGS,F_SUBDIR	   ;AN000;SAY, "A SUBDIR HAS BEEN PRINTED"

	  MOV  DI,CURRENT_COL	   ;AN000;GET COL NUM OF ELBO/TEE
	  LEA  DI,BUF[DI]	   ;AN000;POINT TO JUST AFTER ELBO/TEE
	  MOV  AL,BLANK 	   ;AN000;BLANK OUT THE HORIZONTAL DASHES
	  MOV  CX,DASH_NUM	   ;AN000;HOW MANY DASHES WERE PUT IT
	  REP  STOSB		   ;AN000;WIPE OUT THOSE DASHES FOR NEXT GUY
;     $ENDIF			   ;AN000;
$$IF80:
; $ENDIF			   ;AN000;PERIOD FILENAME?
$$IF77:
  RET				   ;AN000;RETURN TO CALLER
SHOW_FN ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <FLN_TO_BUF - MOVE FILENAME TO BUFFER> ;AN000;
FLN_TO_BUF PROC NEAR		   ;AN000;
  PUBLIC FLN_TO_BUF		   ;AN000;
;INPUT: CURRENT_COL - INDEX INTO "BUF" WHERE THIS DISPLAY STARTS
;	FIX_DTA_FILN - NAME OF FILE TO BE DISPLAYED
;OUTPUT: "BUF" HAS LEADING GRAPHIC AND FILENAME READY FOR DISPLAY.
; =  =	=  =  =  =  =  =  =  =	=  =
  MOV  DI,CURRENT_COL		   ;AN000;
  CMP  BL,ATTR_DIR		   ;AN000;LOOK AT ATTRIB OF FILENAME
; $IF  NE			   ;AN000;IF NOT A SUBDIRECTORY
  JE $$IF83
      LEA  DI,BUF+DASH_NUM+FLN_INDENT[DI] ;AN000;SET DESTINATION TO "BUF"+
; $ELSE 			   ;AN000;SINCE IT IS SUBDIRECTORY
  JMP SHORT $$EN83
$$IF83:
      LEA  DI,BUF+DASH_NUM[DI]	   ;AN000;SET DESTINATION TO "BUF"+
; $ENDIF			   ;AN000;
$$EN83:
  MOV  CX,LENGTH FIX_DTA_FILN	   ;AN000;SET COUNT TO MOVE ENTIRE FILE NAME
  MOV  SI,OFFSET FIX_DTA_FILN	   ;AN000;FROM DTA OF FIND FIRST
; $DO				   ;AN000;
$$DO86:
      LODSB			   ;AN000;GET FIRST\NEXT CHAR OF FILENAME
      STOSB			   ;AN000;MOVE THAT BYTE TO OUTPUT MSG FIELD
      CMP  AL,NUL		   ;AN000;IS THIS THE NUL CHAR DELIMITER?
; $LEAVE E			   ;AN000;QUIT IF NUL FOUND
  JE $$EN86
; $ENDDO LOOP			   ;AN000;
  LOOP $$DO86
$$EN86:
  RET				   ;AN000;RETURN TO CALLER
FLN_TO_BUF ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <GRAF_TO_BUF - SELECT LEADING GRAPHIC CHAR FOR BUF> ;AN000;
GRAF_TO_BUF PROC NEAR		   ;AN000;
  PUBLIC GRAF_TO_BUF		   ;AN000;
;INPUT: BL = ATTRIBUTE OF FILENAME
;	FLAGS (F_FIRSTIME BIT)
;	FRAM_CHAR = LEADING CHAR, FOR FILENAME DISPLAY
;	CURRENT_COL = WHERE IN BUF TO PUT CHARS
;	BUF = TO RECEIVE LEADING CHAR
;OUTPUT: BUF HAS LEADING CHAR
; =  =	=  =  =  =  =  =  =  =	=  =
  TEST FLAGS,F_SWITCH		   ;AN000;ARE FILENAMES TO BE LISTED
; $IF  Z			   ;AN000;NO, JUST SUBDIRS
  JNZ $$IF89
      OR   FLAGS,F_FIRSTIME	   ;AN000;DO NOT DO FIND FIRST SUBDIR
; $ENDIF			   ;AN000;
$$IF89:
  CMP  BL,ATTR_DIR		   ;AN000;LOOK AT ATTRIB OF FILENAME
; $IF  E			   ;AN000;IF A SUBDIR
  JNE $$IF91
      CALL ANY_MORE_SUBDIR	   ;AN000;SEE IF ANOTHER SUBDIR AFTER THIS ONE

; $ELSE 			   ;AN000;SINCE NOT A SUBDIR
  JMP SHORT $$EN91
$$IF91:
      TEST FLAGS,F_FIRSTIME	   ;AN000;IS THIS THE FIRST TIME HERE?
;     $IF  Z			   ;AN000;IF FIRST TIME,
      JNZ $$IF93
	  CALL FIX_GRAF 	   ;AN000;SET UP GRAPHIC FOR NEXT LINE

;     $ENDIF			   ;AN000;FIRST TIME?
$$IF93:
; $ENDIF			   ;AN000;SUBDIR?
$$EN91:
  OR   FLAGS,F_FIRSTIME 	   ;AN000;FLAG, THIS HAS BEEN DONE
  MOV  AL,[BP].FRAM_CHAR	   ;AN000;START BUF WITH CURRENT GRAPHIC CHAR
  MOV  DI,CURRENT_COL		   ;AN000;
  LEA  DI,BUF-1[DI]	   ;AN000;
  STOSB 			   ;AN000;
  RET				   ;AN000;RETURN TO CALLER
GRAF_TO_BUF ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <BLANK_DASH - PUT BLANKS OR DASHES BEFORE FILENAME> ;AN000;
BLANK_DASH PROC NEAR		   ;AN000;
  PUBLIC BLANK_DASH		   ;AN000;
;INPUT: BL - FILE ATTRIBUTE
;	CURRENT_COL - WHERE THIS DISPLAY STARTS IN "BUF"
;	BUF - PARTLY READY CHARS FOR DISPLAY
;OUTPUT: BUF HAS PROPER CHARS BETWEEN LEADING GRAPHIC AND FILENAME FIELDS.
; =  =	=  =  =  =  =  =  =  =	=  =
  CMP  BL,ATTR_DIR		   ;AN000;LOOK AT ATTRIB OF FILENAME
; $IF  NE			   ;AN000;IF NOT A SUBDIRECTORY
  JE $$IF96
      MOV  AL,BLANK		   ;AN000;PUT IN BLANKS
      MOV  CX,DASH_NUM + FLN_INDENT ;AN000;SPECIFY HOW MANY BLANKS TO PUT IN
; $ELSE 			   ;AN000;SINCE IT IS A SUBDIR
  JMP SHORT $$EN96
$$IF96:
      MOV  AL,GRAF_DASH 	   ;AN000;PUT IN THE DASHES
      MOV  CX,DASH_NUM		   ;AN000;SPECIFY HOW MANY DASHES TO PUT IN
; $ENDIF			   ;AN000;
$$EN96:
  MOV  DI,CURRENT_COL		   ;AN000;GET COL NUM OF ELBO/TEE
  LEA  DI,BUF[DI]		   ;AN000;POINT TO JUST AFTER ELBO/TEE
  REP  STOSB			   ;AN000;ADD DASHES/BLANKS TO PRINT LINE IN "BUF"
  RET				   ;AN000;RETURN TO CALLER
BLANK_DASH ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <FIX_GRAF - CHANGE CURRENT GRAPHIC FOR NEXT LINE> ;AN000;
  PUBLIC FIX_GRAF		   ;AN000;MAKE ENTRY IN LINK MAP
FIX_GRAF PROC NEAR		   ;AN000;
;IN THE WORKAREA, IS A CHAR THAT SHOWS WHAT HAS BEEN FOUND REGARDING ANY
;LOWER LEVELS OF SUBDIRS.
;WHEN DISPLAYING A SUBDIR, THE PRINT LINE STARTS EITHER WITH "ELBO",
;MEANING, NO LOWER LEVELS AFTER THIS ONE, OR WITH "TEE" WHICH MEANS
;THERE IS ANOTHER LEVEL OF SUBDIR BELOW THIS ONE.  AFTER THE DISPLAY,
;THE REST OF THE DISPLAY OF FILENAMES WITHIN THIS SUBDIR, WILL SHOW
;THIS CHARACTER, BUT IN A Revised FORMAT.  THIS SUBROUTINE PERFORMS
;THE MODIFICATION, AS:
;CHANGE "ELBO" TO "BLANK, OR CHANGE "TEE" TO "VERTICAL BAR".
;INPUT: BP=POINTER TO STACK WORKAREA
;	FRAM_CHAR=FIELD IN WORKAREA WITH CHAR TO BE Revised
; =  =	=  =  =  =  =  =  =  =	=  =
  PUSH AX			   ;AN002;SAVE WORK REG
  MOV  AL,GRAF_ELBO		   ;AN002;GET ELBO CHAR
  CMP  [BP].FRAM_CHAR,AL	   ;AN000;FOR NEXT DISPLAY LINE AFTER THIS ONE,
; $IF  E			   ;AN000;IF CURRENT LINE STARTS WITH "ELBO"
  JNE $$IF99
      MOV  [BP].FRAM_CHAR,BLANK    ;AN000;CHANGE IT TO JUST A BLANK
; $ELSE 			   ;AN000;SINCE NOT ELBO
  JMP SHORT $$EN99
$$IF99:
      MOV  AL,GRAF_TEE		   ;AN002;GET THE TEE CHAR
      CMP  [BP].FRAM_CHAR,AL	   ;AC002;CHANGE A "TEE"
;     $IF  E			   ;AN000;
      JNE $$IF101
	  MOV  AL,GRAF_BAR	   ;AN002;GET BAR CHAR
	  MOV  [BP].FRAM_CHAR,AL   ;AC002; TO A VERTICAL "BAR"
;     $ENDIF			   ;AN000;
$$IF101:
; $ENDIF			   ;AN000;ELBO?
$$EN99:
  POP  AX			   ;AN002;RESTORE REG
  RET				   ;AN000;RETURN TO CALLER
FIX_GRAF ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <ANY_SUBDIRS - DISPLAY MSG IF NO SUBDIRS PRINTED> ;AN000;
ANY_SUBDIRS PROC NEAR		   ;AN000;
;INPUT:FLAGS (F_SUBDIR BIT) IS SET IF ANY SUBDIR HAD BEEN DISPLAYED.  IF THIS
;	BIT IS OFF, THEN DISPLAY THE MESSAGE
; =  =	=  =  =  =  =  =  =  =	=  =

  TEST FLAGS,F_SUBDIR		   ;AN000;HAVE ANY SUBDIRS BEEN PRINTED YET?
; $IF  Z			   ;AN000;NO, NONE PRINTED SO FAR
  JNZ $$IF104
      MOV  DI,OFFSET MSGNUM_NOSUB  ;AN000;"No sub-directories exist"
      CALL SENDMSG		   ;AN000;DISPLAY THE MESSAGE

; $ENDIF			   ;AN000;ANY SUBDIRS PRINTED?
$$IF104:
  RET				   ;AN000;RETURN TO CALLER
ANY_SUBDIRS ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <DO_WRITE - SEND STRING TO STDOUT> ;AN000;
DO_WRITE PROC NEAR		   ;AN000;
  PUBLIC DO_WRITE		   ;AN000;
;AFTER THE REQUESTED STRING IS SEND TO STDOUT, IT IS TERMINATED BY CR,LF
;INPUT: DX=OFFSET TO STRING TO BE WRITTEN
;	CX=LENGTH
;OUTPUT: STRING IS SENT TO STDOUT, FOLLOWED BY CR,LF.
;	BX = SAVED AND RESTORED.
; =  =	=  =  =  =  =  =  =  =	=  =

  PUSH BX			   ;AN000;SAVE CALLER'S REG
  MOV  BX,STDOUT		   ;AN000;BX = FILE HANDLE
  DOSCALL WRITE 		   ;AN000;(40H) WRITE FUNCTION

  MOV  DX,OFFSET CRLF		   ;AN000;CLOSE MSG WITH CRLF
  MOV  CX,LEN_CRLF		   ;AN000;
  DOSCALL WRITE 		   ;AN000;(40H) WRITE FUNCTION

  POP  BX			   ;AN000;RESTORE CALLER'S REG
  RET				   ;AN000;RETURN TO CALLER
DO_WRITE ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <IF_NOMOREFILES - ASK EXTENDED ERROR FOR WHY IS ERROR> ;AN000;
IF_NOMOREFILES PROC NEAR	   ;AN000;
  PUBLIC IF_NOMOREFILES 	   ;AN000;
;INPUT - A DOS FUNCTION HAS JUST RETURNED WITH A CARRY INDICATING ERROR
;OUTPUT - AX=EXTENDED ERROR CODE
;	IF THE ERROR IS JUST A NO MORE FILES, CARRY IS CLEAR
;	IF ANY OTHER ERROR, THEN CARRY IS SET, AND "EXITFL" HAS RET CODE
; =  =	=  =  =  =  =  =  =  =	=  =

  CALL GET_EXTERR		   ;AN000;GET THE EXTENDED ERROR TO AX

  CMP  AX,NO_MORE_FILES 	   ;AN000;SEE IF FILE WAS NOT FOUND
; $IF  E			   ;AN000;IF NO MORE FILES,
  JNE $$IF106
      CLC			   ;AN000;INDICATE A NORMAL RETURN
; $ELSE 			   ;AN000;SINCE ERROR IS SOMETHING ELSE
  JMP SHORT $$EN106
$$IF106:
      STC			   ;AN000;INDICATE AN ABNORMAL RETURN
      MOV  EXITFL,EXERR 	   ;AN000;INDICATE A PROBLEM TO RETURN CODE
; $ENDIF			   ;AN000;NO MORE FILES?
$$EN106:

  RET				   ;AN000;RETURN TO CALLER
IF_NOMOREFILES ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <GET_EXTERR - CALL EXTENDED ERROR> ;AN000;
GET_EXTERR PROC NEAR		   ;AN000;
  PUBLIC GET_EXTERR		   ;AN000;
;INPUT - A DOS FUNCTION HAS JUST RETURNED WITH A CARRY INDICATING ERROR
;OUTPUT: AX HAS EXTENDED ERROR CODE
;	NOTE: OTHER REGS, BX, CX, NORMALLY SET BY THE EXTERROR CALL
;	      ARE NOT KEPT.  THESE CONTAIN "LOCUS" AND SECONDARY LEVEL CODES
;	      THAT ARE NOT USED.
; =  =	=  =  =  =  =  =  =  =	=  =
  PUSH BX			   ;AN000;SAVE THE
  PUSH DS			   ;AN000; CALLER'S
  PUSH ES			   ;AN000;  REGISTERS
  PUSH CX			   ;AN000;

  MOV  BX,LEVEL_0		   ;AN000;BX=LEVEL NUMBER
  DOSCALL EXTERROR		   ;AN000;(59H) SET REGS TO SAY WHY PROBLEM

  POP  CX			   ;AN000;RESTORE REGS
  POP  ES			   ;AN000; CLOBBERED BY
  POP  DS			   ;AN000;  THE DOSCALL
  POP  BX			   ;AN000;

  RET				   ;AN000;RETURN TO CALLER
GET_EXTERR ENDP 		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <SENDMSG - PASS IN REGS DATA FROM MSG DESCRIPTOR TO DISP MSG> ;AN000;
SENDMSG PROC NEAR		   ;AN000;
  PUBLIC SENDMSG		   ;AN000;
; INPUT - DI=POINTER TO MSG_DESC STRUC FOR THIS MESSAGE
; OUTPUT - IF CARRY SET, EXTENDED ERROR MSG ATTEMPTED DISPLAYED
;	   IF CARRY CLEAR, ALL OK
;	   IN EITHER CASE, DI AND AX ALTERED, OTHERS OK

;  =  =  =  =  =  =  =	=  =  =  =  =

  PUSH BX			   ;AN000; SAVE CALLER'S REGS
  PUSH CX			   ;AN000;
  PUSH DX			   ;AN000;
  PUSH SI			   ;AN000;

;		 PASS PARMS TO MESSAGE HANDLER IN
;		 THE APPROPRIATE REGISTERS IT NEEDS.
  MOV  AX,[DI].MSG_NUM		   ;AN000; MESSAGE NUMBER
  MOV  BX,[DI].MSG_HANDLE	   ;AN000; HANDLE TO DISPLAY TO
  MOV  SI,[DI].MSG_SUBLIST	   ;AN000; OFFSET IN ES: OF SUBLIST, OR 0 IF NONE
  MOV  CX,[DI].MSG_COUNT	   ;AN000; NUMBER OF %PARMS, 0 IF NONE
  MOV  DX,[DI].MSG_CLASS	   ;AN000; CLASS IN HIGH BYTE, INPUT FUNCTION IN LOW
  CALL SYSDISPMSG		   ;AN000; DISPLAY THE MESSAGE

; $IF  C			   ;AN000; IF THERE IS A PROBLEM,
  JNC $$IF109
				   ; AX=EXTENDED ERROR NUMBER
      MOV  DI,OFFSET MSGNUM_EXTERR ;AN000; GET REST OF ERROR DESCRIPTOR
      MOV  BX,[DI].MSG_HANDLE	   ;AN000; HANDLE TO DISPLAY TO
      MOV  SI,[DI].MSG_SUBLIST	   ;AN000; OFFSET IN ES: OF SUBLIST, OR 0 IF NONE
      MOV  CX,[DI].MSG_COUNT	   ;AN000; NUMBER OF %PARMS, 0 IF NONE
      MOV  DX,[DI].MSG_CLASS	   ;AN000; CLASS IN HIGH BYTE, INPUT FUNCTION IN LOW
      CALL SYSDISPMSG		   ;AN000; TRY TO SAY WHAT HAPPENED

      STC			   ;AN000; REPORT PROBLEM
; $ENDIF			   ;AN000; PROBLEM WITH DISPLAY?
$$IF109:

  POP  SI			   ;AN000; RESTORE CALLER'S REGISTERS
  POP  DX			   ;AN000;
  POP  CX			   ;AN000;
  POP  BX			   ;AN000;

  RET				   ;AN000;RETURN TO CALLER
SENDMSG ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=
  HEADER <BREAK_HANDLER - CONTROL BREAK VECTOR POINTS HERE> ;AN000;
BREAK_HANDLER PROC FAR		   ;AN000;"FAR" HERE IS REQUIRED FOR
  PUBLIC BREAK_HANDLER		   ;AN000; BREAK INTERRUPT HANDLERS
;THE INT 23H VECTOR HAS BEEN SET TO POINT HERE.
;THIS ROUTINE GETS CONTROL IF CONTROL-BREAK IS PRESSED.
;OUTPUT: THE "STC" REQUESTS THAT DOS ABORT WHEN I RETURN.
;	THERE IS NO ERRORLEVEL VALUE TO BE PASSED BACK TO DOS AT THIS POINT.

  CALL RESTORE			   ;AN000;PUT THINGS BACK LIKE THEY WERE

  DOSCALL RET_CD_EXIT,EXCTL	   ;AN000;RETURN TO DOS, WITH CTL-BREAK ERROR CODE
  INT  20H			   ;AN000;IN CASE ABOVE FAILS

;NOTE: THIS IS NOT THE MAIN EXIT FROM "TREE".
;      THE USUAL EXIT IS IN "BEGIN" PROC.
BREAK_HANDLER ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <RESTORE - RETURN TO INITIAL DOS DEFAULT DRIVE> ;AN000;
RESTORE PROC NEAR		   ;AN000;
  PUBLIC RESTORE		   ;AN000;
;SET DOS DEFAULT DRIVE BACK TO THE INITIAL VALUE, AND
; RESTORE THE INITIAL DEFAULT PATH,
; AND THE INITIAL "APPEND" STATE,
; AND THE ORIGINAL CONTROL BREAK VECTOR.
;INPUT - "DEFAULT_DR" SET TO ALPHA LETTER OF ORIGINAL DOS DEFAULT DRIVE.
;	 "START_DR_NUM" SET TO NUMERIC VALUE OF ORIGINAL DOS DEFAULT DRIVE
;	 "DEFAULT_PATH" SET TO ORIGINAL CURRENT PATH OF DOS DEFAULT DRIVE
;	 "APPEND_FLAGS" HAS ORIGINAL STATUS OF /X OF APPEND
;	 "OLDINT23" HAS ORIGINAL OWNER OF CONTROL BREAK VECTOR 23H
;	 "OLDINT24" HAS ORIGINAL OWNER OF CRITICAL ERROR VECTOR 24H
; =  =	=  =  =  =  =  =  =  =	=  =

  TEST FLAGS,F_FAILING		   ;AN000;IS RESTORING SUBDIR PERMITTED?
; $IF  Z,AND			   ;AN000;YES, DO IT
  JNZ $$IF111
  TEST FLAGS,F_DEF_PAT_TAR	   ;AN000;HAS ORIGINAL SUBDIR BE FOUND YET?
; $IF  NZ			   ;AN000;YES, DO IT
  JZ $$IF111

;		RESTORE THE CURRENT SUBDIRECTORY TO ITS ORIGINAL PATH

      MOV  DX,OFFSET DEFAULT_PATH  ;AN000;DS:DX = POINTER TO ASCIIZ STRING
      DOSCALL CHDIR		   ;AN000;(3BH) CHANGE CURRENT DIRECTORY

; $ENDIF			   ;AN000;
$$IF111:

;		RESTORE THE DOS DEFAULT DRIVE TO ITS ORIGINAL DRIVE

  MOV  DL,START_DR_NUM		   ;AN000; DL=DRIVE NUMBER (0=A,1=B)
  DOSCALL SELECT_DISK		   ;AN000;(0EH) SETS DEFAULT DRIVE

;		SET APPEND BACK TO ITS ORIGINAL STATUS

  TEST FLAGS,F_APPEND		   ;AN006;IF DOS VERSION OF APPEND IS ACTIVE
; $IF  NZ			   ;AN006;IT NEEDS TO BE FIXED BACK LIKE IT WAS
  JZ $$IF113
      MOV  AX,SET_APPEND	   ;AN000;RESTORE APPEND TO PREVIOUS /X STATUS
      MOV  BX,APPEND_FLAGS	   ;AC006;GET PREVIOUS STATUS
      INT  2FH			   ;AN000;SET IT BACK AS IT WAS

; $ENDIF			   ;AN006;DOS VERSION OF APPEND?
$$IF113:

;		FIXUP THE CONTROL BREAK VECTOR TO ITS ORIGINAL CONTENTS

  PUSH DS			   ;AN000;SAVE THE SEGREG
  LDS  DX,OLDINT23		   ;AN000;USING THE ORIGINAL CONTENTS OF THE VECTOR
				   ;DS:DX = DWORD POINTER TO BE PUT INTO VECTOR
  DOSCALL SET_VECTOR,VEC_CTLBREAK  ;AN000;(25H) RESTORE THE ORIG INT 23 HANDLER

  POP  DS			   ;AN000;RESTORE THE SEGREG

;		FIXUP THE CRITICAL ERROR VECTOR TO ITS ORIGINAL CONTENTS

  PUSH DS			   ;AN000;SAVE THE SEGREG
  LDS  DX,OLDINT24		   ;AN000;USING THE ORIGINAL CONTENTS OF THE VECTOR
				   ;DS:DX = DWORD POINTER TO BE PUT INTO VECTOR
  DOSCALL SET_VECTOR,VEC_CRITERR   ;AN000;(25H) RESTORE THE ORIG INT 24 HANDLER

  POP  DS			   ;AN000;RESTORE THE SEGREG
  RET				   ;AN000;RETURN TO CALLER
RESTORE ENDP			   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <MYERRORHANDLER - SERVICE CRITICAL ERROR HANDLER> ;AN000;
MYERRORHANDLER PROC NEAR	   ;AN000;
;INPUT: DOS HAS CALLED THE CRITICAL ERROR INTERRUPT, VECTOR 24
;	AL=FAILING DRIVE NUMBER (A:=0; B:=1; ETC.)
;OUTPUT: EITHER TREE IS TERMINATED (ON ABORT OR FAIL), OR
;	AL HAS OPERATOR RESPONSE, AND IRET BACK TO DOS TO HANDLE IT.
; =  =	=  =  =  =  =  =  =  =	=  =
  ASSUME CS:CSEG		   ;AN000;ONLY THE CS REG IS WORTH A HOOT
  ASSUME DS:NOTHING		   ;AN000;
  ASSUME ES:NOTHING		   ;AN000;
  ASSUME SS:NOTHING		   ;AN000;

  PUSH AX			   ;AN000;SAVE FAILING DRIVE NUMBER (A:=0, B:=1, ETC)
  PUSHF 			   ;AN000;SAVE THE FLAGS
				   ;(THIS IS NEEDED BECAUSE THE OLD INT 24
				   ;  HANDLER WILL EXIT WITH AN "IRET")
  CALL DWORD PTR OLDINT24	   ;AN000;INVOKE THE DOS ERROR HANDLER
				   ;RESPONSE WILL BE RETURNED IN AL
				   ;AL=0=IGNORE
				   ;AL=1=RETRY
				   ;AL=2=ABORT
				   ;AL=3=FAIL
  CMP  AL,ABORT 		   ;AN000;DID USER SAY ABORT ?
; $IF  GE			   ;AN000;YES, PROCESS "ABORT"
  JNGE $$IF115
      PUSH CS			   ;AN000;SET UP SEGREGS
      PUSH CS			   ;AN000; SO "RESTORE" WILL LIKE THEM
      POP  ES			   ;AN000;
      POP  DS			   ;AN000;
      ASSUME DS:CSEG,ES:CSEG	   ;AN000;TELL THE ASSEMBLER WHAT I JUST DID
      POP  AX			   ;AN007;GET AL=FAILING DRIVE NUMBER
      MOV  AH,START_DRIVE	   ;AN007;GET THE TARGET DRIVE BEING USED
      SUB  AH,DRIVEA		   ;AN007; A:=0, B:=1, ETC
      CMP  AH,AL		   ;AN007;IS START DRIVE SAME AS FAILING DRIVE?
;     $IF  E			   ;AN007;IF SAME DRIVE
      JNE $$IF116
	  OR   FLAGS,F_FAILING	   ;AN007;REQUEST CHDIR ON FAILING DRIVE NOT TO BE DONE
;     $ENDIF			   ;AN007;
$$IF116:

      CALL RESTORE		   ;AN000;RESTORE ORIGINAL CONDITIONS

      DOSCALL RET_CD_EXIT,EXABORT  ;AN000;QUIT, RETURN ERRORLEVEL CODE TO DOS
; = = = = = = = = = = = = = = = = =
; $ENDIF			   ;AN000;
$$IF115:
  ADD  SP,WORD			   ;AC009;UNDO THE PUSH AX ABOVE
  IRET				   ;AN000;
MYERRORHANDLER ENDP		   ;AN000;
; =  =	=  =  =  =  =  =  =  =	=  =
  HEADER <CHK_DBCS -SEE IF SPECIFIED BYTE IS A DBCS LEAD BYTE> ;AN012;
;*****************************************************************************
; Check DBCS environment
;*****************************************************************************

; Function: Check if a specified byte is in ranges of the DBCS lead bytes
; Input:    AL = Code to be examined
; Output:   If CF is on then a lead byte of DBCS
; Register: FL is used for the output, others are unchanged.

  PUBLIC CHK_DBCS		   ;AN012;
Chk_DBCS PROC			   ;AN012;
  PUSH DS			   ;AN012;save these regs, about to be clobbered
  PUSH SI			   ;AN012;
  LDS  SI,DBCSENV		   ;AN012;GET VECTOR OF DBCS RANGES

  ASSUME DS:NOTHING		   ;AN012;that function clobbered old DS

  OR   SI,SI			   ;AN012;IS THIS VECTOR SET YET?
; $IF  Z			   ;AN012;NO, GO GET THE VECTOR
  JNZ $$IF119
      PUSH AX			   ;AN012;
      DOSCALL DBCS_ENV,GET_DBCS_ENV ;AN012;SET DS:SI TO POINT TO DBCS VECTOR

      MOV  WORD PTR DBCSENV,SI	   ;AN012;SAVE THE DBCS VECTOR OFFSET
      MOV  WORD PTR DBCSENV+WORD,DS ;AN012; AND ITS SEGID
      POP  AX			   ;AN012;REGAIN THE CHAR TO BE CHECKED
; $ENDIF			   ;AN000;
$$IF119:
; $SEARCH			   ;AN012;
$$DO121:
      CMP  WORD PTR [SI],NUL	   ;AN012;vector ends with a nul terminator entry
; $LEAVE E			   ;AN012;if that was the terminator entry, quit
  JE $$EN121
      CMP  AL,[SI]		   ;AN012;look at LOW value of vector
; $EXITIF NB,AND		   ;AN012;if this byte is in range with respect to LOW
  JB $$IF121
      CMP  AL,[SI+1]		   ;AN012;look at HIGH value of vector
; $EXITIF NA			   ;AN012;if this byte is still in range
  JA $$IF121
      STC			   ;AN012;set flag to say, found a DBCS char.
; $ORELSE			   ;AN012;since char not in this vector
  JMP SHORT $$SR121
$$IF121:
      ADD  SI,WORD		   ;AN012;go look at next vector in dbcs table
; $ENDLOOP			   ;AN012;go back and check out new vector entry
  JMP SHORT $$DO121
$$EN121:
      CLC			   ;AN012;set flag to say this is not a DBCS character
; $ENDSRCH			   ;AN012;
$$SR121:
  POP  SI			   ;AN012;restore the regs
  POP  DS			   ;AN012;

  ASSUME DS:CSEG		   ;AN012;tell masm, DS back to normal

  RET				   ;AN012;
Chk_DBCS ENDP			   ;AN012;
; =  =	=  =  =  =  =  =  =  =	=  =
  PATHLABL TREE 		   ;AN013;
CSEG ENDS			   ;AN000;
  END  START			   ;AN000;