v4.0/src/CMD/DEBUG/DEBUG.ASM

   1         PAGE    60,132                  ;\ f
   2         TITLE   DEBUG.SAL - DEBUGger for PC DOS
   3
   4 ;======================= START OF SPECIFICATIONS =========================
   5 ;
   6 ; MODULE NAME: DEBUG.SAL
   7 ;
   8 ; DESCRIPTIVE NAME: DEBUGGING TOOL
   9 ;
  10 ; FUNCTION: PROVIDES USERS WITH A TOOL FOR DEBUGGING PROGRAMS.
  11 ;
  12 ; ENTRY POINT: START
  13 ;
  14 ; INPUT: DOS COMMAND LINE
  15 ;        DEBUG COMMANDS
  16 ;
  17 ; EXIT NORMAL: NA
  18 ;
  19 ; EXIT ERROR: NA
  20 ;
  21 ; INTERNAL REFERENCES:
  22 ;
  23 ; EXTERNAL REFERENCES:
  24 ;
  25 ;       ROUTINE: DEBCOM1 - CONTAINS ROUTINES CALLED BY DEBUG
  26 ;                DEBCOM2 - CONTAINS ROUTINES CALLED BY DEBUG
  27 ;                DEBCOM3 - CONTAINS ROUTINES CALLED BY DEBUG
  28 ;                DEBASM  - CONTAINS ROUTINES CALLED BY DEBUG
  29 ;                DEBUASM - CONTAINS ROUTINES CALLED BY DEBUG
  30 ;                DEBMES  - CONTAINS MESSAGE RETRIEVER ROUTINES
  31 ;
  32 ; NOTES: THIS MODULE IS TO BE PREPPED BY SALUT WITH THE "PR" OPTIONS.
  33 ;        LINK DEBUG+DEBCOM1+DEBCOM2+DEBCOM3+DEBASM+DEBUASM+DEBERR+
  34 ;             DEBCONST+DEBDATA+DEBMES
  35 ;
  36 ; REVISION HISTORY:
  37 ;
  38 ;       AN000   VERSION 4.00 - REVISIONS MADE RELATE TO THE FOLLOWING:
  39 ;
  40 ;                               - IMPLEMENT DBCS HANDLING       DMS:6/17/87
  41 ;                               - IMPLEMENT DBCS HANDLING       bgb:5/03/88     ;an001;bgb
  42 ;                               - IMPLEMENT MESSAGE RETRIEVER   DMS:6/17/87
  43 ;                               - > 32 MB SUPPORT               DMS:6/17/87
  44 ;
  45 ; COPYRIGHT: "MS DOS DEBUG UTILITY"
  46 ;            "VERSION 4.00 (C) COPYRIGHT 1988 Microsoft"
  47 ;            "LICENSED MATERIAL - PROPERTY OF Microsoft  "
  48 ;
  49 ;       MICROSOFT REVISION HISTORY:
  50 ;
  51 ; Modified 5/4/82 by AaronR to do all I/O direct to devices
  52 ; Runs on MS-DOS 1.28 and above
  53 ;
  54 ; REV 1.20
  55 ;       Tab expansion
  56 ;       New device interface (1.29 and above)
  57 ; REV 2.0
  58 ;       line by line assembler added by C. P.
  59 ; REV 2.1
  60 ;       Uses EXEC system call
  61 ; REV 2.2
  62 ;       Ztrace mode by zibo.
  63 ;       Fix dump display to indent properly
  64 ;       Parity nonsense by zibo
  65 ;
  66 ; REV 2.3 NP
  67 ;       Use Printf for all standard output.
  68 ;       Change to EXE file
  69 ; REV 2.4 ARR
  70 ;       Bug fixes. TEST, XCHG instructions reg order reversed.
  71 ;       Single step, break point interrupts saved and restored.
  72 ;       Access denied given on W to read only file.
  73 ;======================= END OF SPECIFICATIONS ===========================
  74
  75         IF1
  76             %OUT    COMPONENT=DEBUG, MODULE=DEBUG
  77         ENDIF
  78 .XLIST
  79 .XCREF
  80         INCLUDE DOSSYM.INC              ; ALSO VERSION NUMBER
  81 .CREF
  82 .LIST
  83         INCLUDE DEBEQU.ASM
  84         IF      SYSVER
  85 ; Structure for system call 72
  86 SYSINITVAR  STRUC
  87 DPBHEAD     DD      ?                   ; Pointer to head of DPB-FAT list
  88 SFT_ADDR    DD      ?                   ; Pointer to first FCB table
  89 ; The following address points to the CLOCK device
  90 BCLOCK      DD      ?
  91 ; The following address is used by DISKSTATCHK it is always
  92 ; points to the console input device header
  93 BCON        DD      ?                   ; Console device entry points
  94 MAXSEC      DW      0                   ; Maximum allowed sector size
  95 BUFFHEAD    DD      ?
  96 CDS         DD      ?
  97 SFTFCB      DD      ?
  98 KEEP        DW      ?
  99 NUMIO       DB      0                   ; Number of disk tables
 100 NCDS        DB      ?
 101 DEVHEAD     DD      ?
 102 SYSINITVAR  ENDS
 103
 104         ENDIF
 105
 106
 107 ;======================= macro equates ===================================
 108
 109 dbcs_delim equ  81h                     ;an000;delimits dbcs char
 110 asian_blk equ   40h                     ;an000;asian blank
 111 amer_blk equ    20h                     ;an000;american blank
 112 quote_char equ  22h                     ;an000;quote delim "
 113
 114 ;======================= end macro equates ===============================
 115
 116
 117 ;This segment must be the first loaded since we are using it to make
 118 ;a CREATE_PROCESS_DATA_BLOCK system call a la 1.0 and .COM files.
 119 ;For this system call CS must point to the Program Prefix Header, so
 120 ;by setting up a seperate segment just after the header we can issue
 121 ;an INT 21H via a long call.  So don't move this guy around!
 122
 123 A_CREATE_BLOCK SEGMENT
 124
 125         PUBLIC  CREATE_CALL
 126
 127 ;The other arguements to this system call have been set up
 128 ;by the caller.
 129
 130 CREATE_CALL PROC FAR
 131         MOV     AH,CREATE_PROCESS_DATA_BLOCK
 132         INT     21H
 133         RET
 134
 135 CREATE_CALL ENDP
 136
 137 A_CREATE_BLOCK ENDS
 138
 139
 140 CODE    SEGMENT PUBLIC
 141 CODE    ENDS
 142
 143 CONST   SEGMENT PUBLIC
 144 CONST   ENDS
 145
 146 CSTACK  SEGMENT STACK
 147 CSTACK  ENDS
 148
 149 DATA    SEGMENT PUBLIC
 150 DATA    ENDS
 151
 152 DG      GROUP   CODE,CONST,CSTACK,DATA
 153
 154 CONST   SEGMENT PUBLIC BYTE
 155         EXTRN   BADVER:BYTE,ENDMES_PTR:BYTE,CRLF_PTR:BYTE
 156         IF      IBMJAPAN
 157             EXTRN   PARITYMES_PTR:BYTE
 158         ENDIF
 159         EXTRN   PROMPT_PTR:BYTE,ADD_PTR:BYTE,HEX_PTR:BYTE
 160         EXTRN   USER_PROC_PDB:WORD,CSSAVE:WORD,DSSAVE:WORD
 161         EXTRN   SPSAVE:WORD,IPSAVE:WORD,LINEBUF:BYTE,QFLAG:BYTE
 162         EXTRN   NEWEXEC:BYTE,HEADSAVE:WORD,LBUFSIZ:BYTE,BACMES_PTR:WORD
 163
 164         IF      IBMVER
 165             EXTRN   DSIZ:BYTE,NOREGL:BYTE,DISPB:WORD
 166         ENDIF
 167
 168         IF      SYSVER
 169             EXTRN   CONFCB:BYTE,POUT:DWORD,COUT:DWORD,CIN:DWORD,IOBUFF:BYTE
 170             EXTRN   IOADDR:DWORD,IOCALL:BYTE,IOCOM:BYTE,IOSTAT:WORD,IOCNT:WORD
 171             EXTRN   IOSEG:WORD,COLPOS:BYTE,BADDEV_PTR:BYTE,BADLSTMES_PTR:BYTE
 172             EXTRN   LBUFFCNT:BYTE,PFLAG:BYTE
 173         ENDIF
 174
 175         EXTRN   NAMESPEC:BYTE
 176
 177 CONST   ENDS
 178
 179 CSTACK  SEGMENT STACK
 180         DB      (362 - 80H) + 80H DUP(?) ; (362 - 80H) == IBM'S ROM REQUIREMENTS
 181                                         ; (NEW - OLD) == SIZE TO GROW STACK
 182 CSTACK  ENDS
 183
 184 DATA    SEGMENT PUBLIC BYTE
 185         EXTRN   ARG_BUF:BYTE,ADD_ARG:WORD,SUB_ARG:WORD,HEX_ARG1:WORD
 186         EXTRN   HEX_ARG2:WORD,STACK:BYTE, PREV24:DWORD, FIN24:BYTE
 187         EXTRN   PARSERR:BYTE,DATAEND:WORD,PARITYFLAG:BYTE,DISADD:BYTE
 188         EXTRN   ASMADD:BYTE,DEFDUMP:BYTE,BYTEBUF:BYTE,BEGSEG:WORD
 189         EXTRN   BPINTSAV:DWORD,SSINTSAV:DWORD ;ARR 2.4
 190         EXTRN   CREATE_LONG:DWORD
 191
 192         extrn   lbtbl:dword             ;an000;lead byte table pointer
 193
 194 DATA    ENDS
 195
 196         EXTRN   PRINTF:NEAR             ;ac000;changed to NEAR call
 197
 198 CODE    SEGMENT PUBLIC
 199         ASSUME  CS:DG,DS:NOTHING,ES:NOTHING,SS:CSTACK
 200
 201         PUBLIC  RESTART
 202         PUBLIC  STD_PRINTF,PRINTF_CRLF
 203         PUBLIC  HEX_ADDRESS_ONLY,HEX_ADDRESS_STR
 204         PUBLIC  RESTART,SET_TERMINATE_VECTOR,DABORT,TERMINATE,COMMAND
 205         PUBLIC  FIND_DEBUG,CRLF,BLANK,TAB,INBUF,SCANB,SCANP
 206         PUBLIC  HEX,OUTSI,OUTDI,DIGIT,BACKUP,RBUFIN
 207         public  test_lead                                                       ;an001;bgb
 208         public  test1                                                           ;an001;bgb
 209
 210         IF      SYSVER
 211 ;           PUBLIC  SETUDEV,DEVIOCALL                           ; kwc 12/10/86
 212             PUBLIC  SETUDEV             ; kwc 12/10/86
 213             EXTRN   DISPREG:NEAR,INPT:NEAR
 214         ENDIF
 215
 216         EXTRN   PERR:NEAR,COMPARE:NEAR,DUMP:NEAR,ENTERDATA:NEAR,FILL:NEAR
 217         EXTRN   GO:NEAR,INPUT:NEAR,LOAD:NEAR,MOVE:NEAR,NAMED:NEAR
 218         EXTRN   REG:NEAR,SEARCH:NEAR,DWRITE:NEAR,UNASSEM:NEAR,ASSEM:NEAR
 219         EXTRN   OUTPUT:NEAR,ZTRACE:NEAR,TRACE:NEAR,GETHEX:NEAR,GETEOL:NEAR
 220         EXTRN   PREPNAME:NEAR,DEFIO:NEAR,SKIP_FILE:NEAR,DEBUG_FOUND:NEAR
 221         EXTRN   TRAPPARITY:NEAR,RELEASEPARITY:NEAR
 222         extrn   pre_load_message:near   ;an000;load messages
 223         extrn   debems:near             ;an000;ems support
 224
 225
 226         DB      100H DUP (?)
 227
 228 START:
 229         JMP     SHORT DSTRT
 230
 231 HEADER  DB      "Vers 2.40"
 232
 233 DSTRT:
 234 ;=========================================================================
 235 ; invoke PRE_LOAD_MESSAGE here.  If the messages were not loaded we will
 236 ; exit with an appropriate error message.
 237 ;
 238 ;       Date       : 6/14/87
 239 ;=========================================================================
 240
 241         push    ds                      ;an000;save regs
 242         push    es                      ;an000;save resg
 243
 244         push    cs                      ;an000;transfer cs
 245         pop     ds                      ;an000;    to ds
 246
 247         push    cs                      ;an000;transfer cs
 248         pop     es                      ;an000;    to es
 249         assume  ds:dg,es:dg             ;an000;assume them
 250         call    PRE_LOAD_MESSAGE        ;an000;invoke SYSLOADMSG
 251 ;       $if     c                       ;an000;if the load was unsuccessful
 252         JNC $$IF1
 253             mov     ax,(exit shl 8)     ;an000;exit EDLIN.  PRE_LOAD_MESSAGE
 254                                         ;      has already said why
 255             int     21h                 ;an000;exit
 256 ;       $endif                          ;an000;
 257 $$IF1:
 258
 259         pop     es                      ;an000;restore regs.
 260         pop     ds                      ;an000;
 261         assume  ds:nothing,es:nothing   ;an000;back to original
 262
 263         MOV     AX,(GET_INTERRUPT_VECTOR SHL 8) OR VEC_BREAKPOINT ;get original contents
 264         INT     21H                     ;  of the BREAKPOINT vector
 265
 266         MOV     WORD PTR [BPINTSAV],BX  ;  and save that vector for later
 267         MOV     WORD PTR [BPINTSAV+WORD],ES ; restoration
 268
 269         MOV     AX,(GET_INTERRUPT_VECTOR SHL 8) OR VEC_SING_STEP ;get original contents
 270         INT     21H                     ;  of the SINGLE STEP vector
 271
 272         MOV     WORD PTR [SSINTSAV],BX  ;  and save that vector for later
 273         MOV     WORD PTR [SSINTSAV+WORD],ES ; restoration
 274
 275         MOV     BEGSEG,DS               ; save beginning DS
 276         PUSH    CS                      ; repair damaged ES to be
 277         POP     ES                      ;  back to just like CS
 278         XOR     SI,SI                   ; set source and destination
 279         XOR     DI,DI                   ;  indices both to zero
 280         MOV     CX,256                  ; set count to size of PSP
 281         REP     MOVSB                   ; move to es:[di] from ds:[si]
 282         PUSH    CS                      ; set up DS to be just like CS
 283         POP     DS                      ;  to match .COM rules of addressability
 284         ASSUME  DS:DG,ES:DG             ; like CS, also have DS and DS as bases
 285
 286         CALL    TRAPPARITY              ; scarf up those parity guys
 287         MOV     AH,GET_CURRENT_PDB      ;(undocumented function call - 51h)
 288         INT     21H
 289
 290         MOV     [USER_PROC_PDB],BX      ; Initially set to DEBUG
 291
 292         IF      SYSVER
 293             MOV     [IOSEG],CS
 294         ENDIF
 295
 296         MOV     [PARSERR],AL
 297
 298
 299         IF      SYSVER
 300             MOV     AH,GET_IN_VARS      ;(undocumented function call - 52h)
 301             INT     21H
 302
 303             LDS     SI,ES:[BX.BCON]     ; get system console device
 304             ASSUME  DS:NOTHING
 305
 306             MOV     WORD PTR CS:[CIN+WORD],DS ;save vector to console input device
 307             MOV     WORD PTR CS:[CIN],SI
 308             MOV     WORD PTR CS:[COUT+WORD],DS ;save vector to console output device
 309             MOV     WORD PTR CS:[COUT],SI
 310             PUSH    CS                  ; restore DS to be
 311             POP     DS                  ;  just like CS, as before
 312             ASSUME  DS:DG
 313
 314             MOV     DX,OFFSET DG:CONFCB ; get system printer device
 315             MOV     AH,FCB_OPEN         ; open system printer "PRN"
 316             INT     21H
 317
 318             OR      AL,AL               ; open ok?
 319             JZ      GOTLIST             ; yes, it was there
 320
 321             MOV     DX,OFFSET DG:BADLSTMES_ptr ; no list file found...
 322             CALL    STD_PRINTF          ; tell user
 323
 324             CALL    RBUFIN              ; ask for a new one
 325
 326             CALL    CRLF
 327
 328             MOV     CL,[LBUFFCNT]
 329             OR      CL,CL
 330             JZ      NOLIST1             ; User didn't specify one
 331
 332             XOR     CH,CH
 333             MOV     DI,OFFSET DG:(CONFCB + BYTE)
 334             MOV     SI,OFFSET DG:LINEBUF ; get one from input line
 335             REP     MOVSB
 336             MOV     DX,OFFSET DG:CONFCB
 337             MOV     AH,FCB_OPEN         ; try to open it
 338             INT     21H
 339
 340             OR      AL,AL
 341             JZ      GOTLIST             ; yep, use it...
 342
 343             MOV     DX,OFFSET DG:BADDEV_Ptr ; complain again
 344             CALL    STD_PRINTF
 345 NOLIST1:                                ; kwc 12/10/86
 346             MOV     WORD PTR [POUT+WORD],CS ; use null device for printer
 347             MOV     WORD PTR [POUT],OFFSET DG:LONGRET
 348             JMP     NOLIST
 349
 350 XXX         PROC    FAR
 351 LONGRET:
 352             RET
 353 XXX         ENDP
 354         ENDIF
 355
 356 GOTLIST:
 357 ;DX = OFFSET OF 'CONFCB', WHICH HAS JUST BEEN OPENED OK
 358         IF      SYSVER
 359             MOV     SI,DX
 360 ;           LDS     SI,DWORD PTR DS:[SI.FCB_FIRCLUS]            ; KWC 12/10/86
 361             LDS     SI,DWORD PTR DS:[SI.FCB_NSLD_DRVPTR] ; KWC 12/10/86
 362             ASSUME  DS:NOTHING
 363
 364             MOV     WORD PTR CS:[POUT+WORD],DS
 365             MOV     WORD PTR CS:[POUT],SI
 366         ENDIF
 367 NOLIST:
 368         MOV     AX,CS                   ;restore the DS and ES segregs
 369         MOV     DS,AX                   ; to become once again just like CS
 370         MOV     ES,AX
 371         ASSUME  DS:DG,ES:DG
 372
 373 ; Code to print header
 374 ;       MOV     DX,OFFSET DG:HEADER_PTR
 375 ;       CALL    STD_PRINTF
 376
 377         CALL    SET_TERMINATE_VECTOR
 378
 379 ; Save the current INT 24 vector.  We will need this to link to the previous
 380 ; handler for handling of int 24 output.
 381         PUSH    ES                      ; save it, about to clobber it...
 382         MOV     AX,(GET_INTERRUPT_VECTOR SHL 8) + VEC_CRIT_ERR ; get original contents
 383         INT     21H                     ; of the int 24h vector
 384
 385         MOV     WORD PTR PREV24,BX      ; remember what int 24h used to
 386         MOV     WORD PTR PREV24+WORD,ES ;  point to
 387         POP     ES                      ; restore ES to be like CS and DS
 388
 389         MOV     AX,(SET_INTERRUPT_VECTOR SHL 8) + VEC_CRIT_ERR ; change int 24h to
 390         MOV     DX,OFFSET DG:MY24       ; point to my own int 24h handler
 391         INT     21H
 392
 393         IF      SETCNTC
 394             MOV     AL,VEC_CTRL_BREAK   ; Set vector 23H
 395             MOV     DX,OFFSET DG:DABORT
 396             INT     21H
 397         ENDIF
 398
 399         MOV     DX,CS                   ;get para of where this pgm starts
 400         MOV     AX,OFFSET DG:DATAEND+15 ;get offset of end of this program
 401         MOV     CL,4                    ; (plus 15 padding for rounding)
 402         SHR     AX,CL                   ; adjusted to number of paragraphs
 403         ADD     DX,AX                   ;get para of where this pgm ends
 404         MOV     AX,CS
 405         SUB     AX,BEGSEG               ; add in size of printf
 406         ADD     DX,AX                   ; create program segment here
 407         CALL    [CREATE_LONG]           ; and call special routine
 408
 409         MOV     AX,DX
 410 ; Initialize the segments
 411         MOV     DI,OFFSET DG:DSSAVE
 412         CLD
 413         STOSW
 414         STOSW
 415         STOSW
 416         STOSW
 417         MOV     WORD PTR [DISADD+WORD],AX
 418         MOV     WORD PTR [ASMADD+WORD],AX
 419         MOV     WORD PTR [DEFDUMP+WORD],AX
 420
 421         MOV     AX,100H
 422         MOV     WORD PTR[DISADD],AX
 423         MOV     WORD PTR[ASMADD],AX
 424         MOV     WORD PTR [DEFDUMP],AX
 425
 426         MOV     DS,DX
 427         MOV     ES,DX
 428         ASSUME  DS:NOTHING,ES:NOTHING
 429
 430         MOV     DX,80H
 431         MOV     AH,SET_DMA
 432         INT     21H                     ; Set default DMA address to 80H
 433 ; Set up initial stack.  We already have a 'good' stack set up already.  DS:6
 434 ; has the number of bytes remaining in the segment.  We should take this
 435 ; value, add 100h and use it as the Stack pointer.
 436         MOV     AX,WORD PTR DS:[6]      ; get bytes remaining
 437         MOV     BX,AX
 438         ADD     AX,100h
 439
 440 ;       MOV     BX,AX
 441 ;       CMP     AX,0FFF0H
 442 ;       PUSH    CS
 443 ;       POP     DS
 444 ;       JAE     SAVSTK
 445 ;       MOV     AX,WORD PTR DS:[6]
 446 ;       PUSH    BX
 447 ;       MOV     BX,OFFSET DG:DATAEND + 15
 448 ;       AND     BX,0FFF0H               ; Size of DEBUG in bytes (rounded up to PARA)
 449 ;       SUB     AX,BX
 450 ;       POP     BX
 451 ;SAVSTK:
 452         PUSH    CS
 453         POP     DS
 454         ASSUME  DS:DG
 455         PUSH    BX                      ; bx is no. bytes remaining from PSP+6
 456         DEC     AX                      ; ax was no. bytes remaining +100h
 457         DEC     AX                      ; back up one word from end of new stack
 458         MOV     BX,AX                   ; set base to point to last word in new stack
 459         MOV     WORD PTR ES:[BX],0      ; set final word in new stack to zero
 460         POP     BX                      ; back to beginning of new stack area
 461         MOV     SPSAVE,AX               ; remember where new stack is
 462         DEC     AH
 463         MOV     ES:WORD PTR [6],AX      ; change PSP to show usage of
 464         SUB     BX,AX                   ; new stack area
 465         MOV     CL,4
 466         SHR     BX,CL
 467         ADD     ES:WORD PTR [8],BX
 468
 469         IF      IBMVER
 470 ; Get screen size and initialize display related variables
 471             MOV     AH,15               ;function = "request current video state"
 472             INT     10H                 ;set al=screen mode
 473                                         ;    ah=no. char cols on screen
 474                                         ;    bh=current active display page
 475             CMP     AH,40               ;is screen in 40 col mode?
 476             JNZ     PARSCHK             ; no, skip
 477                                         ; yes, 40 col, continue
 478                                         ;next fields defined in 'debconst.asm'
 479             MOV     BYTE PTR DSIZ,7     ; originally assembled as 0fh
 480             MOV     BYTE PTR NOREGL,4   ; originally assembled as 8
 481             MOV     DISPB,64            ; originally assembled as 128
 482         ENDIF
 483
 484 PARSCHK:
 485
 486
 487         call    DEBUG_LEAD_BYTE         ;an000;build the dbcs env. table
 488                                         ;      of valid dbcs lead bytes
 489
 490 ;=========================================================================
 491 ; prep_command_line requires the use of ds:si.  ds is left intact for
 492 ; the call.  si is initialized to point to the command line input buffer.
 493 ; ds and si are saved since we stomp all over them in prep_command_line.
 494 ;=========================================================================
 495
 496         push    si                      ;an000;save si
 497
 498         mov     si,81h                  ;an000;point to command line
 499         call    prep_command_line       ;an000;invoke command line conversion
 500
 501         pop     si                      ;an000;restore si
 502
 503 ;=========================================================================
 504 ; we have prepped the command line for dbcs.  we can now enter the old
 505 ; routines.
 506 ;=========================================================================
 507
 508 ; Copy rest of command line to test program's parameter area
 509         MOV     DI,FCB                  ;es[di]=to be filled with unopened FCB
 510         MOV     SI,81H                  ;ds[si]=command line to parse
 511         MOV     AX,(PARSE_FILE_DESCRIPTOR SHL 8) OR SET_DRIVEID_OPTION
 512                                         ;func=29H, option al=1, which
 513                                         ; says, drive id byte in fcb is set
 514                                         ; only if drive specified in command
 515                                         ; line being parsed.
 516         INT     21H                     ;parse filename from command to fcb
 517                                         ; ds:si=points to first char AFTER parsed filename
 518                                         ; es:di=points to first byte of formatted FCB
 519
 520         CALL    SKIP_FILE               ; Make sure si points to delimiter
 521 test1:                                  ;for testing only - u can remove this
 522         CALL    PREPNAME
 523
 524         PUSH    CS                      ;restore ES to point to the
 525         POP     ES                      ;  common group
 526 FILECHK:
 527         MOV     DI,80H                  ;point to byte in PSP defining parm length
 528         CMP     BYTE PTR ES:[DI],0      ; ANY STUFF FOUND?
 529         JZ      COMMAND                 ; no parms, skip
 530                                         ; yes parms, continue
 531 FILOOP:
 532         INC     DI                      ;set index to first/next char in parm text
 533         CMP     BYTE PTR ES:[DI],CR     ; carriage return? (at end of parms)
 534         JZ      COMMAND                 ; yes, at end of parms
 535                                         ; no, not at end of parms yet, continue
 536         CMP     BYTE PTR ES:[DI],CHAR_BLANK ; is this parm text char a blank?
 537         JZ      FILOOP                  ; yes, a blank, skip
 538                                         ; no, not a blank, continue
 539         CMP     BYTE PTR ES:[DI],CHAR_TAB ; is this parm text char a tab?
 540         JZ      FILOOP                  ; yes, a tab, skip
 541                                         ; no, not a tab, continue
 542         OR      [NAMESPEC],1            ; set flag to indicate
 543                                         ;  we have a specified file
 544                                         ; (this could be set by "N" command also)
 545         CALL    DEFIO                   ; READ in the specified file
 546
 547         PUSH    CS                      ;restore DS to point to the
 548         POP     DS                      ; common group
 549
 550                                         ;perform self-relocation on some internal vectors:
 551         MOV     AX,CSSAVE               ; pick up the seg id to go to vectors
 552         MOV     WORD PTR DISADD+WORD,AX ;  shove it into the segid portion
 553         MOV     WORD PTR ASMADD+WORD,AX ;  of these two vectors
 554         MOV     AX,IPSAVE               ; pick up the offset to go to vectors
 555         MOV     WORD PTR DISADD,AX      ;  shove it into the offset portion
 556         MOV     WORD PTR ASMADD,AX      ;  of these two vectors
 557 COMMAND:
 558         CLD
 559         MOV     AX,CS
 560         MOV     DS,AX
 561         MOV     ES,AX
 562         cli                             ;disable before setting up the stack - EMK
 563         MOV     SS,AX                   ;now everything points to the same group
 564         ASSUME  SS:DG
 565
 566         MOV     SP,OFFSET DG:STACK
 567         STI                             ;re-enable
 568         CMP     [PARITYFLAG],0          ; did we detect a parity error?
 569         JZ      GOPROMPT                ; no, go prompt
 570                                         ; yes, parity error, continue
 571         MOV     [PARITYFLAG],0          ; reset flag
 572         IF      IBMJAPAN
 573             MOV     DX,OFFSET DG:PARITYMES_PTR
 574             CALL    STD_PRINTF          ;display msg about parity error
 575         ENDIF
 576 GOPROMPT:
 577         MOV     DX,OFFSET DG:PROMPT_PTR ;display the user prompt request
 578         CALL    STD_PRINTF
 579
 580         CALL    INBUF                   ; Get command line
 581 ; From now and throughout command line processing, DI points
 582 ; to next character in command line to be processed.
 583         CALL    SCANB                   ; Scan off leading blanks
 584
 585         JZ      COMMAND                 ; if zero, Null command, go get another
 586                                         ; nonzero, got something in response
 587         LODSB                           ; AL=first non-blank character
 588 ; Prepare command letter for table lookup
 589 ; converts the first non-blank (assumed to be the command letter)
 590 ; to in index in the "comtab" array.
 591         SUB     AL,UPPER_A              ; Low end range check
 592         JB      ERR1
 593
 594         CMP     AL,UPPER_Z - UPPER_A    ; Upper end range check
 595         JA      ERR1
 596
 597         SHL     AL,1                    ; Times two
 598         CBW                             ; Now a 16-bit quantity
 599         XCHG    BX,AX                   ; In BX we can address with it
 600         CALL    CS:[BX+COMTAB]          ; Execute command
 601
 602         JMP     SHORT COMMAND           ; Get next command
 603 ERR1:
 604         JMP     PERR
 605
 606 SET_TERMINATE_VECTOR:
 607         PUSH    DS
 608         PUSH    CS
 609         POP     DS
 610         MOV     AX,(SET_INTERRUPT_VECTOR SHL 8) OR VEC_TERM_ADDR ; Set vector 22H
 611         MOV     DX,OFFSET DG:TERMINATE
 612         INT     21H
 613
 614         POP     DS
 615         RET
 616
 617 RESTORE_DEB_VECT:
 618         PUSH    DS
 619         PUSH    DX
 620         PUSH    AX
 621         LDS     DX,CS:[BPINTSAV]
 622         MOV     AX,(SET_INTERRUPT_VECTOR SHL 8) OR VEC_BREAKPOINT ;Vector 3
 623         INT     21H
 624
 625         LDS     DX,CS:[SSINTSAV]
 626         MOV     AX,(SET_INTERRUPT_VECTOR SHL 8) OR VEC_SING_STEP ;Vector 1
 627         INT     21H
 628
 629         POP     AX
 630         POP     DX
 631         POP     DS
 632         RET
 633
 634 ; Internal INT 24 handler.  We allow our parent's handler to decide what to do
 635 ; and how to prompt.  When our parent returns, we note the return in AL.  If
 636 ; he said ABORT, we need to see if we are aborting ourselves.  If so, we
 637 ; cannot turn it into fail; we may get a cascade of errors due to the original
 638 ; cause.  Instead, we do the ol' disk-reset hack to clean up.  This involves
 639 ; issuing a disk-reset, ignoring all errors, and then returning to the caller.
 640 MY24:
 641         ASSUME  DS:NOTHING,ES:NOTHING,SS:NOTHING
 642
 643 ; If we are already inside an INT 24, just ignore this error
 644         TEST    FIN24,-1
 645         JZ      DO24
 646
 647         MOV     AL,0                    ; signal ignore
 648         IRET
 649
 650 ; Let the user decide what to do
 651 DO24:
 652         PUSHF
 653         CALL    PREV24                  ; simulate INT 24 to him
 654
 655         CMP     AL,2                    ; was it ABORT?
 656         JNZ     DOIRET                  ; no, let it happen
 657
 658         PUSH    AX
 659         PUSH    BX
 660         MOV     AH,GET_CURRENT_PDB      ; find out who's terminating
 661         INT     21H
 662
 663         CMP     BX,BEGSEG               ; is it us?
 664         POP     BX
 665         POP     AX
 666         JZ      DORESET                 ; no, let it happen
 667
 668 DOIRET:
 669         IRET
 670
 671 ; We have been instructed to abort ourselves.  Since we can't do this, we will
 672 ; perform a disk reset to flush out all buffers and then ignore the errors we
 673 ; get.
 674 DORESET:
 675         MOV     FIN24,-1                ; signal that we ignore errors
 676         MOV     AH,DISK_RESET
 677         INT     21H                     ; clean out cache
 678
 679         MOV     FIN24,0                 ; reset flag
 680         JMP     COMMAND
 681
 682 TERMINATE:
 683         ASSUME  DS:NOTHING,ES:NOTHING,SS:NOTHING
 684
 685         CMP     QFLAG,0
 686         JNZ     QUITING
 687
 688         MOV     AX,BEGSEG
 689         MOV     USER_PROC_PDB,AX
 690         CMP     NEWEXEC,0
 691         JZ      NORMTERM
 692
 693         MOV     AX,CS
 694         MOV     DS,AX
 695         ASSUME  DS:DG
 696                                         ;is CLI/STI needed here ? - emk
 697         CLI
 698         MOV     SS,AX
 699         ASSUME  SS:DG
 700
 701         MOV     SP,OFFSET DG:STACK
 702         STI
 703         MOV     AX,HEADSAVE
 704         JMP     DEBUG_FOUND
 705
 706 NORMTERM:
 707         ASSUME  DS:NOTHING,ES:NOTHING,SS:NOTHING
 708
 709         PUSH    CS
 710         POP     DS
 711         ASSUME  DS:DG
 712
 713         MOV     DX,OFFSET DG:ENDMES_PTR
 714         JMP     SHORT RESTART
 715
 716 QUITING:
 717         ASSUME  DS:NOTHING,ES:NOTHING,SS:NOTHING
 718
 719         CALL    RESTORE_DEB_VECT
 720
 721         MOV     AX,(EXIT SHL 8)
 722         INT     21H
 723
 724 RESTART:
 725         CALL    STD_PRINTF
 726 DABORT:
 727         MOV     AX,CS
 728         MOV     DS,AX
 729         ASSUME  DS:DG
 730
 731                                         ;is CLI\STI needed here? - emk
 732         CLI
 733         MOV     SS,AX
 734         ASSUME  SS:DG
 735
 736         MOV     SP,OFFSET DG:STACK
 737         STI
 738 ;;;;;;  CALL    CRLF
 739
 740         JMP     COMMAND
 741
 742         IF      SYSVER
 743 SETUDEV:
 744             MOV     DI,OFFSET DG:CONFCB
 745             MOV     AX,(PARSE_FILE_DESCRIPTOR SHL 8) OR SET_DRIVEID_OPTION
 746             INT     21H
 747
 748             CALL    USERDEV
 749
 750             JMP     DISPREG
 751
 752 USERDEV:
 753             MOV     DX,OFFSET DG:CONFCB
 754             MOV     AH,FCB_OPEN
 755             INT     21H
 756
 757             OR      AL,AL
 758             JNZ     OPENERR
 759
 760             MOV     SI,DX
 761 ;           TEST    BYTE PTR [SI.FCB_DEVID],080H ; Device?      ; KWC 12/10/86
 762 ;           JZ      OPENERR             ; NO                    ; KWC 12/10/86
 763             MOV     AL,BYTE PTR [SI.FCB_NSL_DRIVE] ; KWC 12/10/86
 764             AND     AL,NOT FCBMASK      ; KWC 12/10/86
 765             CMP     AL,0C0H             ; KWC 12/10/86
 766             JNE     OPENERR             ; KWC 12/10/86
 767             XOR     AL,AL               ; KWC 12/10/86
 768
 769 ;           LDS     SI,DWORD PTR [CONFCB.FCB_FIRCLUS]           ; KWC 12/10/86
 770             LDS     SI,DWORD PTR [CONFCB.FCB_NSLD_DRVPTR] ; KWC 12/10/86
 771             MOV     WORD PTR CS:[CIN],SI
 772             MOV     WORD PTR CS:[CIN+WORD],DS
 773
 774             MOV     WORD PTR CS:[COUT],SI
 775             MOV     WORD PTR CS:[COUT+WORD],DS
 776             PUSH    CS
 777             POP     DS
 778             RET
 779
 780 OPENERR:
 781             MOV     DX,OFFSET DG:BADDEV_PTR
 782             CALL    STD_PRINTF
 783
 784             RET
 785         ENDIF
 786 ; Get input line. Convert all characters NOT in quotes to upper case.
 787 INBUF:
 788         CALL    RBUFIN
 789
 790 ;=========================================================================
 791 ; prep_command_line requires the use of ds:si.  ds is left intact for
 792 ; the call.  si is initialized to point to the command line input buffer.
 793 ; ds and si are saved since we stomp all over them in prep_command_line.
 794 ;=========================================================================
 795
 796         push    si                      ;an000;save si
 797
 798         mov     si,offset dg:linebuf    ;an000;point to command line
 799         call    prep_command_line       ;an000;invoke command line conversion
 800
 801         pop     si                      ;an000;restore si
 802
 803 ;=========================================================================
 804 ; we have prepped the command line for dbcs.  we can now enter the old
 805 ; routines.
 806 ;=========================================================================
 807
 808         MOV     SI,OFFSET DG:LINEBUF
 809         MOV     DI,OFFSET DG:BYTEBUF
 810
 811 CASECHK:
 812
 813         LODSB
 814
 815         call    Test_Lead                       ;DBCS lead byte                 ;an000; dms;
 816 ;       $if     c                               ;yes - ignore 2nd. byte         ;an000; dms;
 817         JNC $$IF3
 818                 stosb                           ;save the byte                  ;an000; dms;
 819                 lodsb                           ;pick up the 2nd. character     ;an000; dms;
 820                 stosb                           ;save it also                   ;an000; dms;
 821                 jmp     CaseChk                 ;read next character            ;an000; dms;
 822 ;       $endif                                  ;                               ;an000; dms;
 823 $$IF3:
 824
 825         CMP     AL,LOWER_A
 826         JB      NOCONV
 827
 828         CMP     AL,LOWER_Z
 829         JA      NOCONV
 830
 831         ADD     AL,UPPER_A - LOWER_A    ; Convert to upper case
 832 NOCONV:
 833         STOSB
 834         CMP     AL,CR
 835         JZ      INDONE
 836
 837         CMP     AL,DOUBLE_QUOTE
 838         JZ      QUOTSCAN
 839
 840         CMP     AL,SINGLE_QUOTE
 841         JNZ     CASECHK
 842
 843 QUOTSCAN:
 844         MOV     AH,AL
 845 KILLSTR:
 846         LODSB
 847         STOSB
 848         CMP     AL,CR                   ;CARRIAGE RETURN?
 849         JZ      INDONE
 850
 851         CMP     AL,AH
 852         JNZ     KILLSTR
 853
 854         JMP     SHORT CASECHK
 855
 856 INDONE:
 857         MOV     SI,OFFSET DG:BYTEBUF
 858         CALL    CRLF
 859
 860         RET
 861
 862 ; Physical backspace - blank, backspace, blank
 863 BACKUP:
 864         PUSH    DX
 865         MOV     DX,OFFSET DG:BACMES_PTR
 866         CALL    STD_PRINTF
 867
 868         POP     DX
 869         RET
 870
 871 ; Scan for parameters of a command
 872 SCANP:
 873         CALL    SCANB                   ; Get first non-blank
 874
 875         CMP     BYTE PTR [SI],CHAR_COMMA ; One comma between params OK
 876         JNE     EOLCHK                  ; If not comma, we found param
 877
 878         INC     SI                      ; Skip over comma
 879 ; Scan command line for next non-blank character
 880 SCANB:
 881         PUSH    AX
 882 SCANNEXT:
 883         LODSB
 884         CMP     AL,CHAR_BLANK           ;is this char a "blank"?
 885         JZ      SCANNEXT
 886
 887         CMP     AL,CHAR_TAB             ;is this char a "tab"?
 888         JZ      SCANNEXT
 889
 890         DEC     SI                      ; Back to first non-blank
 891         POP     AX
 892 EOLCHK:
 893         CMP     BYTE PTR [SI],CR        ;CARRIAGE RETURN
 894         RET
 895
 896 ; Hex addition and subtraction
 897 HEXADD:
 898         MOV     CX,4
 899         CALL    GETHEX
 900
 901         MOV     DI,DX
 902         MOV     CX,4
 903         CALL    GETHEX
 904
 905         CALL    GETEOL
 906
 907         PUSH    DX
 908         ADD     DX,DI
 909         MOV     [ADD_ARG],DX
 910         POP     DX
 911         SUB     DI,DX
 912         MOV     [SUB_ARG],DI
 913         MOV     DX,OFFSET DG:ADD_PTR
 914         CALL    PRINTF_CRLF
 915
 916         RET
 917
 918 ; Put the hex address in DS:SI in the argument list for a call to printf
 919 OUTSI:
 920         MOV     CS:[HEX_ARG1],DS
 921         MOV     CS:[HEX_ARG2],SI
 922         RET
 923
 924 ;Put the hex address in ES:DI in the argument list for a call to printf
 925 OUTDI:
 926         MOV     [HEX_ARG1],ES
 927         MOV     [HEX_ARG2],DI
 928         RET
 929
 930 HEX_ADDRESS_ONLY:
 931         MOV     BYTE PTR [ARG_BUF],0
 932 HEX_ADDRESS_STR:
 933         MOV     DX,OFFSET DG:HEX_PTR
 934 STD_PRINTF:
 935         PUSH    DX
 936         CALL    PRINTF
 937         POP     DX                      ;ac000;restore dx
 938
 939         RET
 940
 941 PRINTF_CRLF:
 942         PUSH    DX
 943         CALL    PRINTF
 944         POP     DX                      ;ac000;restore dx
 945 CRLF:
 946         MOV     DX,OFFSET DG:CRLF_PTR
 947         PUSH    DX
 948         CALL    PRINTF
 949         POP     DX                      ;ac000;restore dx
 950
 951         RET
 952
 953 HEX:
 954         MOV     AH,AL                   ; Save for second digit
 955         PUSH    CX
 956         MOV     CL,4
 957         SHR     AL,CL
 958         POP     CX
 959
 960         CALL    DIGIT                   ; First digit
 961
 962         MOV     AL,AH                   ; Now do digit saved in AH
 963 DIGIT:
 964         AND     AL,0FH                  ; Mask to 4 bits
 965         ADD     AL,90H
 966         DAA
 967         ADC     AL,40H
 968         DAA
 969         AND     AL,7FH
 970         STOSB
 971         RET
 972
 973 RBUFIN:
 974         PUSH    AX
 975         PUSH    DX
 976         MOV     AH,STD_CON_STRING_INPUT
 977         MOV     DX,OFFSET DG:LBUFSIZ
 978         INT     21H
 979
 980         POP     DX
 981         POP     AX
 982         RET
 983
 984 ; Put one space in the printf output uffer
 985 BLANK:
 986         MOV     AL,CHAR_BLANK
 987         STOSB
 988         RET
 989
 990 ; Put CX spaces in the printf output buffer
 991 TAB:
 992         JCXZ    TAB_RET
 993
 994         CALL    BLANK
 995
 996         LOOP    TAB
 997 TAB_RET:
 998         RET
 999
1000 ; Command Table. Command letter indexes into table to get
1001 ; address of command. PERR prints error for no such command.
1002
1003 COMTAB  DW      ASSEM                   ; A
1004         DW      PERR                    ; B
1005         DW      COMPARE                 ; C
1006         DW      DUMP                    ; D
1007         DW      ENTERDATA               ; E
1008         DW      FILL                    ; F
1009         DW      GO                      ; G
1010         DW      HEXADD                  ; H
1011         DW      INPUT                   ; I
1012         DW      PERR                    ; J
1013         DW      PERR                    ; K
1014         DW      LOAD                    ; L
1015         DW      MOVE                    ; M
1016         DW      NAMED                   ; N
1017         DW      OUTPUT                  ; O
1018         DW      ZTRACE                  ; P
1019         DW      QUIT                    ; Q (QUIT)
1020         DW      REG                     ; R
1021         DW      SEARCH                  ; S
1022         DW      TRACE                   ; T
1023         DW      UNASSEM                 ; U
1024         DW      PERR                    ; V
1025         DW      DWRITE                  ; W
1026         IF      SYSVER
1027             DW      SETUDEV             ; X
1028         ELSE
1029             DW      DEBEMS
1030         ENDIF
1031         DW      PERR                    ; Y
1032         DW      PERR                    ; Z
1033
1034 QUIT:
1035         INC     BYTE PTR [QFLAG]
1036         MOV     BX,[USER_PROC_PDB]
1037 FIND_DEBUG:
1038         IF      NOT SYSVER
1039             MOV     AH,SET_CURRENT_PDB
1040             INT     21H
1041         ENDIF
1042         CALL    RELEASEPARITY           ; let system do normal parity stuff
1043
1044         CALL    RESTORE_DEB_VECT
1045
1046         MOV     AX,(EXIT SHL 8)
1047         INT     21H
1048
1049 ;======================= proc  prep_command_line =========================
1050 ; prep_command_line: This proc converts a Asian DBCS space delimiter (8140h)
1051 ;                    into 2 20h values.  In this way we can pass command
1052 ;                    lines throughout DEBUG without major modification
1053 ;                    to the source code.  This proc is invoked anywhere
1054 ;                    a command line is initially accessed.  In the case
1055 ;                    of DEBUG it is used in PARSCHK and INBUF.
1056 ;                    Any quoted string, a string delimited by ("), will
1057 ;                    be ignored.
1058 ;
1059 ;       input: ds - segment of command line
1060 ;              si - offset of command line
1061 ;
1062 ;       output: command line with Asian blanks (8140h) converted to
1063 ;               2020h.
1064 ;
1065 ;=========================================================================
1066
1067 prep_command_line proc near             ;command line conversion
1068     push    ax                          ;save affected regs.
1069     push    bx                          ;
1070     push    si                          ;
1071
1072     mov     bl,00h                      ;initialize flag
1073                                         ;bl is used to signal
1074                                         ;  a quote delimiter
1075 ;   $DO                                 ;do while not CR
1076 $$DO5:
1077         mov     al,[si]                 ;move char from cmd line for compare
1078         cmp     al,CR                   ;is it a CR ?
1079 ;   $LEAVE  E                           ;if CR exit
1080     JE $$EN5
1081
1082         cmp     al,quote_char           ;is it a quote ?
1083 ;       $IF     Z                       ;if it is a quote
1084         JNZ $$IF7
1085             xor     bl,01h              ;set or reset the flag
1086 ;       $ENDIF
1087 $$IF7:
1088
1089         cmp     bl,01h                  ;is 1st quote set ?
1090 ;       $IF     NZ                      ;if not continue
1091         JZ $$IF9
1092             call    TEST_LEAD           ;test for dbcs lead byte
1093 ;           $IF     C                   ;we have a lead byte
1094             JNC $$IF10
1095                 cmp     al,dbcs_delim   ;is it a dbcs char? 81h
1096 ;               $IF     Z               ;if a dbcs char
1097                 JNZ $$IF11
1098                     mov     al,[si+1]       ;move next char al
1099                     cmp     al,asian_blk    ;is it an Asian blank? 40h
1100 ;                   $IF     Z               ;if an Asian blank
1101                     JNZ $$IF12
1102                         mov     al,amer_blk ;set up moves
1103                         mov     [si],al     ;  to replace
1104                         mov     [si+1],al   ;  Asian blank w/20h
1105                         inc     si          ;point to si+1
1106 ;                   $ELSE               ;if not an asian blank
1107                     JMP SHORT $$EN12
1108 $$IF12:
1109                         inc     si      ;point to dbcs char
1110 ;                   $ENDIF              ;
1111 $$EN12:
1112 ;               $ENDIF                  ;
1113 $$IF11:
1114 ;           $ENDIF                      ;end lead byte test
1115 $$IF10:
1116 ;       $ENDIF                          ;
1117 $$IF9:
1118         inc     si                      ;point to si+1
1119 ;   $ENDDO                              ;end do while
1120     JMP SHORT $$DO5
1121 $$EN5:
1122     pop     si                          ;restore affected regs.
1123     pop     bx                          ;
1124     pop     ax                          ;
1125     ret                                 ;return to caller
1126 prep_command_line endp                  ;end proc
1127
1128
1129 ;=========================================================================
1130 ; DEBUG_LEAD_BYTE - This routine sets the lead-byte-pointers to point
1131 ;                   to the dbcs environmental vector table of lead bytes.
1132 ;                   This table will be used to determine if we have a
1133 ;                   dbcs lead byte.
1134 ;
1135 ;       Inputs - none
1136 ;
1137 ;       Outputs- pointer to dbcs environmental vector table of lead bytes
1138 ;                LBTBL DD ?
1139 ;
1140 ;       Date      : 6/16/87
1141 ;=========================================================================
1142
1143 DEBUG_LEAD_BYTE proc near               ;an000;get lead byte vector
1144
1145         push    ds                      ;an000;save affected regs
1146         push    es                      ;an000;
1147         push    si                      ;an000;
1148
1149         mov     ax,(ECS_call shl 8) or 00h ;an000;get dbcs env. vector
1150         int     21h                     ;an000;invoke function
1151
1152         assume  ds:nothing
1153
1154         mov     word ptr cs:lbtbl[0],si ;an000;move offset of table
1155         mov     word ptr cs:lbtbl[2],ds ;an000;move segment of table
1156
1157         pop     si                      ;an000;restore affected regs
1158         pop     es                      ;an000;
1159         pop     ds                      ;an000;
1160
1161         ret                             ;an000;return to caller
1162
1163 DEBUG_LEAD_BYTE endp                    ;an000;end proc
1164
1165 ;=========================================================================
1166 ; TEST_LEAD - This routine will determine whether or not we have a valid
1167 ;             lead byte for a DBCS character.
1168 ;
1169 ;       Inputs : AL - Holds the byte to compare.  Passed by POP.                ;an001;bgb
1170 ;
1171 ;       Outputs: Carry set if lead byte
1172 ;                No carry if not lead byte
1173 ;
1174 ;       Date      : 6/16/87
1175 ;=========================================================================
1176
1177 TEST_LEAD proc  near                    ;an000;check for dbcs lead byte
1178
1179         push    ds                      ;an000;save affected regs
1180         push    si                      ;an000;
1181         push    ax                      ;an000;
1182
1183         xchg    ah,al                   ;an000;ah used for compare
1184         mov     si,word ptr cs:lbtbl[2] ;an000;get segment of table
1185         mov     ds,si                   ;an000;
1186         mov     si,word ptr cs:lbtbl[0] ;an000;get offset of table
1187
1188 ck_next:
1189
1190         lodsb                           ;an000;load al with byte table
1191         or      al,al                   ;an000;end of table?
1192 ;       $IF     z                       ;an000;yes, end of table
1193         JNZ $$IF19
1194             jmp     lead_exit           ;an000;exit with clear carry
1195 ;       $ELSE                           ;an000;
1196         JMP SHORT $$EN19
1197 $$IF19:
1198             cmp     al,ah               ;an000;start > character?
1199 ;           $IF     a                   ;an000;it is above
1200             JNA $$IF21
1201                 clc                     ;an000;clear carry flag
1202                 jmp     lead_exit       ;an000;exit with clear carry
1203 ;           $ELSE                       ;an000;
1204             JMP SHORT $$EN21
1205 $$IF21:
1206                 lodsb                   ;an000;load al with byte table
1207                 cmp     ah,al           ;an000;character > end range
1208 ;               $IF     a               ;an000;not a lead
1209                 JNA $$IF23
1210                     jmp     ck_next     ;an000;check next range
1211 ;               $ELSE                   ;an000;lead byte found
1212                 JMP SHORT $$EN23
1213 $$IF23:
1214                     stc                 ;an000;set carry flag
1215 ;               $ENDIF                  ;an000;
1216 $$EN23:
1217 ;           $ENDIF                      ;an000;
1218 $$EN21:
1219 ;       $ENDIF                          ;an000;
1220 $$EN19:
1221
1222 lead_exit:                              ;an000;exit from check
1223
1224         pop     ax                      ;an000;
1225         pop     si                      ;an000;restore affected regs.
1226         pop     ds                      ;an000;
1227
1228         ret                             ;an000;return to caller
1229
1230 TEST_LEAD endp                          ;an000;end proc
1231
1232
1233
1234 CODE    ENDS
1235         END     START
1236 \1a