; Copyright (c) 2009-2010, Michael Alyn Miller <malyn@strangeGizmo.com>.
; All rights reserved.
;
; Redistribution and use in source and binary forms, with or without
; modification, are permitted provided that the following conditions are met:
;
; 1. Redistributions of source code must retain the above copyright notice
; unmodified, this list of conditions, and the following disclaimer.
; 2. Redistributions in binary form must reproduce the above copyright notice,
; this list of conditions and the following disclaimer in the documentation
; and/or other materials provided with the distribution.
; 3. Neither the name of Michael Alyn Miller nor the names of the contributors
; to this software may be used to endorse or promote products derived from
; this software without specific prior written permission.
;
; THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND ANY
; EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
; DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
; DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
; (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
; ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
; THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
; ======================================================================
; STRING Words
; ======================================================================
; ----------------------------------------------------------------------
; /STRING [STRING] 17.6.1.0245 "slash-string" ( c-addr1 u1 n -- c-addr2 u2 )
;
; Adjust the character string at c-addr1 by n characters. The resulting
; character string, specified by c-addr2 u2, begins at c-addr1 plus n
; characters and is u1 minus n characters long.
LINKTO(LINK_STRING,0,7,'G',"NIRTS/")
SLASHSTRING:SAVEDE
MOV D,B ; Save BC
MOV E,C ; ..in DE.
POP B ; Pop the adjustment value into BC.
POP H ; Pop the length into HL.
DSUB ; Adjust the length.
XTHL ; Swap the adjusted length with the address.
DAD B ; Adjust the address.
XTHL ; Swap the address and length again.
PUSH H ; Push the length onto the stack.
MOV B,D ; Restore BC
MOV C,E ; ..from DE.
RESTOREDE
NEXT
; ----------------------------------------------------------------------
; CMOVE [STRING] 17.6.1.0910 "c-move" ( c-addr1 c-addr2 u -- )
;
; If u is greater than zero, copy u consecutive characters from the data
; space starting at c-addr1 to that starting at c-addr2, proceeding
; character-by-character from lower addresses to higher addresses.
LINKTO(SLASHSTRING,0,5,'E',"VOMC")
CMOVE: SAVEDE
SAVEBC
POP B ; Pop u into BC.
POP D ; Pop addr2 into DE.
POP H ; Pop addr1 into HL.
_cmove1: MOV A,B ; We're done if B
ORA C ; ..and C
JZ _cmoveDONE ; ..are zero.
MOV A,M ; Copy the next byte from [HL]
STAX D ; ..to [DE]
INX H ; ..and then increment both HL
INX D ; ..and DE.
DCX B ; Decrement BC
JMP _cmove1 ; ..and continue looping.
_cmoveDONE: RESTOREBC
RESTOREDE
NEXT
; ----------------------------------------------------------------------
; CMOVE> [STRING] 17.6.1.0920 "c-move-up" ( c-addr1 c-addr2 u -- )
;
; If u is greater than zero, copy u consecutive characters from the data
; space starting at c-addr1 to that starting at c-addr2, proceeding
; character-by-character from higher addresses to lower addresses.
LINKTO(CMOVE,0,6,'>',"EVOMC")
LAST_STRING:
CMOVEUP: SAVEDE
SAVEBC
POP B ; Pop u into BC.
POP D ; Pop addr2 into DE.
POP H ; Pop addr1 into HL.
DAD B ; Add u to addr1.
XCHG ; Swap addr1 and addr2,
DAD B ; ..add u to addr2,
XCHG ; ..then swap addr2 and addr1 again.
_cmoveup1: MOV A,B ; We're done if B
ORA C ; ..and C
JZ _cmoveupDONE; ..are zero.
DCX H ; Decrement both HL
DCX D ; ..and DE.
MOV A,M ; Copy the next byte from [HL]
STAX D ; ..to [DE].
DCX B ; Decrement BC
JMP _cmoveup1 ; ..and continue looping.
_cmoveupDONE:RESTOREBC
RESTOREDE
NEXT
