From cf49ca3d0ae82295664fff720763d87c950c7510 Mon Sep 17 00:00:00 2001
From: cuz <cuz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Sun, 21 Dec 2003 10:56:34 +0000
Subject: [PATCH] New mainargs module from Stefan Haubenthal

git-svn-id: svn://svn.cc65.org/cc65/trunk@2804 b7a2c559-68d2-44c3-8de9-860c34a00d81
---
 libsrc/apple2/mainargs.s | 128 ++++++++++++++++++++++++++++++++++++---
 1 file changed, 120 insertions(+), 8 deletions(-)

diff --git a/libsrc/apple2/mainargs.s b/libsrc/apple2/mainargs.s
index ebe6d0348..f44812149 100644
--- a/libsrc/apple2/mainargs.s
+++ b/libsrc/apple2/mainargs.s
@@ -1,21 +1,133 @@
+; mainargs.s
 ;
 ; Ullrich von Bassewitz, 2003-03-07
+; Based on code from Stefan A. Haubenthal <polluks@web.de>, 2003-11-08
+; Greg King, 2003-05-18
 ;
-; Setup arguments for main
+; Scan a group of arguments that are in BASIC's input-buffer.
+; Build an array that points to the beginning of each argument.
+; Send, to main(), that array and the count of the arguments.
+
+; Command-lines look like these lines:
+;
+; call2048
+; call2048 : rem  no arguments because no comma!
+; call2048:rem,arg1," arg 2" , arg 3 ,, arg5, ...
+;
+; "call" and "rem" are entokenned; the args. are not.  Leading spaces are
+; ignored; trailing spaces are included -- unless the argument was quoted.
+
+; TO-DO:
+; - The "file-name" might be a path-name; don't copy the directory-components.
+; - Add a control-character quoting mechanism.
+
+	.constructor	initmainargs, 24
+	.import		__argc, __argv
+
+	.include	"apple2.inc"
+
+; Maximum number of arguments allowed in the argument table.
+; (An argument contains a comma, at least.)
+;
+BASIC_BUF = $200
+BASIC_BUF_LEN = 239
+FNAM_LEN = $280
+FNAM = $281
+MAXARGS	 = BASIC_BUF_LEN - 2	; (don't count REM and terminating '\0')
+
+REM	 = $b2			; BASIC token-code
+NAME_LEN = 15			; maximum length of command-name
+
+; Get possible command-line arguments.
 ;
+initmainargs:
 
+; Assume that the program was loaded, a moment ago, by the traditional LOAD
+; statement.  Save the "most-recent filename" as argument #0.
+; Because the buffer, that we're copying into, was zeroed out,
+; we don't need to add a NUL character.
+;
+	ldy	FNAM_LEN
+	cpy	#NAME_LEN + 1
+	bcc	L1
+	ldy	#NAME_LEN - 1	; limit the length
+L0:	lda	FNAM,y
+	sta	name,y
+L1:	dey
+	bpl	L0
+	lda	#<name
+	ldx	#>name
+	sta	argv
+	stx	argv + 1
+	inc	__argc		; argc always is equal to, at least, 1
 
-	.constructor    initmainargs, 24
-       	.import         __argc, __argv
+; Find the "rem" token.
+;
+	ldx	#0
+L2:	lda	BASIC_BUF,x
+	beq	done		; no "rem," no args.
+	inx
+	cmp	#REM
+	bne	L2
+	ldy	#1 * 2
 
+; Find the next argument.
+;
+next:	lda	BASIC_BUF,x
+	beq	done
+	inx
+	cmp	#','		; look for argument-list separator
+	bne	next
+	lda	#$00
+	sta	BASIC_BUF-1,x	; make the previous arg. be a legal C string
+	inc	__argc		; found another arg.
 
-;---------------------------------------------------------------------------
-; Setup arguments for main
+L4:	lda	BASIC_BUF,x
+	beq	point		; zero-length argument
+	inx
+	cmp	#' '
+	beq	L4		; skip leading spaces
 
-.proc   initmainargs
+	cmp	#'"'		; is argument quoted?
+	beq	L5
+	dex			; no, don't skip over character
+	clc			; (quotation-mark sets flag)
+L5:	ror	quoted		; save it
 
-        rts
+; BASIC's input-buffer starts at the beginning of a RAM page.
+; So, we don't need to add the offset -- just store it.
+;
+point:	txa
+	sta	argv,y		; argv[y]= &arg
+	iny
+	lda	#>BASIC_BUF
+	sta	argv,y
+	iny
 
-.endproc
+	asl	quoted		; is argument a string-literal?
+	bcc	next		; no, don't look for ending quotation-mark
+L7:	lda	BASIC_BUF,x
+	beq	done
+	inx
+	cmp	#'"'
+	bne	L7
+	lda	#$00
+	sta	BASIC_BUF-1,x	; make this arg. be a legal C string
+	beq	next		;(bra)
 
+; (The last vector in argv[] already is NULL.)
+;
+done:	lda	#<argv
+	ldx	#>argv
+	sta	__argv
+	stx	__argv + 1
+	rts
 
+; These arrays are zeroed before initmainargs is called.
+; char	name[16+1];
+; char* argv[MAXARGS+1]={name};
+;
+	.bss
+quoted:	.res	1, %00000000
+name:	.res	NAME_LEN + 1
+argv:	.res	(MAXARGS + 1) * 2
-- 
2.39.5