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mirror of https://github.com/cc65/cc65.git synced 2024-11-18 15:05:14 +00:00

Merge pull request #102 from greg-king5/main-args

Added command-line argument parsing to the CBM510 and CBM610 targets.
This commit is contained in:
Oliver Schmidt 2014-04-04 09:55:31 +03:00
commit cb2c78a3de
6 changed files with 381 additions and 80 deletions

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@ -4,7 +4,7 @@
; Taken from a kernal disassembly done by myself in 2000/2001.
;
; 2001-09-13, Ullrich von Bassewitz
; 2013-08-26, Greg King
; 2014-04-02, Greg King
;-----------------------------------------------------------------------------
@ -14,6 +14,8 @@ ExecReg := $00 ; Controls execution memory bank
IndReg := $01 ; Controls indirect indexed load-store bank
TXTPTR := $85 ; Far pointer into BASIC source code
FNAM := $90 ; Far pointer to LOAD/SAVE file-name
FNAM_LEN := $9D ; Holds length of file-name
; ---------------------------------------------------------------------------
; Screen size

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@ -4,7 +4,7 @@
; Taken from a kernal disassembly done by myself in 1987.
;
; 1998-09-28, Ullrich von Bassewitz
; 2013-08-26, Greg King
; 2014-04-02, Greg King
; ---------------------------------------------------------------------------
@ -14,6 +14,8 @@ ExecReg := $00 ; Controls execution memory bank
IndReg := $01 ; Controls indirect indexed load-store bank
TXTPTR := $85 ; Far pointer into BASIC source code
FNAM := $90 ; Far pointer to LOAD/SAVE file-name
FNAM_LEN := $9D ; Holds length of file-name
; ---------------------------------------------------------------------------
; Screen size

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@ -6,7 +6,7 @@
<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org"><newline>
Stefan A. Haubenthal, <htmlurl url="mailto:polluks@sdf.lonestar.org" name="polluks@sdf.lonestar.org"><newline>
<url url="mailto:greg.king5@verizon.net" name="Greg King">
<date>2014-03-26
<date>2014-04-02
<abstract>
An overview over the Commodore 510 runtime system as it is implemented for the
@ -38,10 +38,10 @@ machines are supported by this cc65 target.
<sect>Binary format<p>
The standard binary output format generated by the linker for the Commodore
510 target is a machine language program with a one line BASIC stub, which
transfers control to the machine language running in bank 0. This means that a
program can be loaded as BASIC program and started with RUN. It is of course
possible to change this behaviour by using a modified startup file and linker
510 target is a machine language program with a one-line BASIC stub, which
transfers control to the machine language running in bank 0. That means that a
program can be loaded as a BASIC program, and started with RUN. It is, of course,
possible to change that behaviour by using a modified startup file and linker
config.
@ -58,7 +58,7 @@ The default memory configuration for the CBM 510 allocates all memory between
in low memory is lost, because a separate hardware stack is set up in page 1,
and the kernal replacement functions need some more memory locations. A few
more pages are lost in high memory, because the runtime sets up a copy of the
character ROM, a text screen and a CBM compatible jump table at &dollar;FF81.
character ROM, a text screen, and a CBM-compatible jump table at &dollar;FF81.
The main startup code is located at &dollar;0400, so about 54K of the complete
bank are actually usable for applications.
@ -66,10 +66,10 @@ Special locations:
<descrip>
<tag/Stack/
The C runtime stack is located at &dollar;FF81 and growing downwards.
The C runtime stack is located at &dollar;FF81, and grows downwards.
<tag/Heap/
The C heap is located at the end of the program and grows towards the C
The C heap is located at the end of the program, and grows towards the C
runtime stack.
</descrip><p>
@ -79,7 +79,7 @@ Special locations:
Programs containing CBM 510-specific code may use the <tt/cbm510.h/ or
<tt/cbm.h/ header files. Using the later may be an option when writing code
for more than one CBM platform, since it includes <tt/cbm510.h/ and declares
for more than one CBM platform, since it includes <tt/cbm510.h/, and declares
several functions common to all CBM platforms.
<sect1>CBM 510-specific functions<p>
@ -133,11 +133,11 @@ declaration and usage.
The following pseudo variables declared in the <tt/cbm510.h/ header file do
allow access to hardware located in the address space. Some variables are
structures, accessing the struct fields will access the chip registers.
structures; accessing the struct fields will access the chip registers.
<bf>Note:</bf> All I/O chips are located in the system bank (bank 15) and can
<bf>Note:</bf> All I/O chips are located in the system bank (bank 15); and can
therefore not be accessed like on other platforms. Please use one of the
<tt/peekbsys/, <tt/peekwsys/, <tt/pokebsys/ and <tt/pokewsys/ functions to
<tt/peekbsys/, <tt/peekwsys/, <tt/pokebsys/, and <tt/pokewsys/ functions to
access the I/O chips. Direct reads and writes to the structures named below
will <em>not</em> work!
@ -164,7 +164,7 @@ will <em>not</em> work!
declaration of the structure.
<tag><tt/TPI1, TPI2/</tag>
The two 6525 triport chips may be accessed by using this variable. See the
The two 6525 triport chips may be accessed by using these variables. See the
<tt/_6525.h/ header file located in the include directory for the
declaration of the structure.
@ -196,7 +196,7 @@ No graphics drivers are currently available for the Commodore 510.
<descrip>
<tag><tt/cbm510-std.joy (cbm510_std_joy)/</tag>
Supports up to two standard joysticks connected to the joysticks port of
Supports up to two standard joysticks connected to the joysticks ports of
the Commodore 510.
</descrip><p>
@ -247,17 +247,17 @@ Since the program runs in bank 0, and the kernal and all I/O chips are located
in bank 15, calling ROM routines or accessing hardware needs special code. The
cc65 runtime implements wrappers for all functions in the kernal jump table.
While this simplifies things, it should be noted that the wrappers do have
quite an impact on performance: A cross bank call has an extra 300&micro;s
quite an impact on performance: A cross-bank call has an extra 300&micro;s
penalty added by the wrapper.
<sect1>Interrupts<p>
Compiled programs contain an interrupt handler that runs in the program bank.
This has several advantages, one of them being performance (see cross bank
This has several advantages, one of them being performance (see cross-bank
call overhead mentioned above). However, this introduces one problem:
Interrupts are lost while the CPU executes code in the kernal bank. As a
result, the clock may go wrong and (worse) serial interrupts may get lost.
result, the clock may go wrong; and (worse), serial interrupts may get lost.
Since the cc65 runtime does only call the kernal for disk I/O, this means that
a program should not do file I/O while it depends on interrupts.
@ -269,8 +269,22 @@ a program should not do file I/O while it depends on interrupts.
<sect1>Passing arguments to the program<p>
Command line argument passing is currently not supported for the Commodore
510.
Command-line arguments can be passed to <tt/main()/. Since that is not
supported directly by BASIC, the following syntax was chosen:
<tscreen><verb>
RUN:REM ARG1 " ARG2 IS QUOTED" ARG3 "" ARG5
</verb></tscreen>
<enum>
<item>Arguments are separated by spaces.
<item>Arguments may be quoted.
<item>Leading and trailing spaces around an argument are ignored. Spaces within
a quoted argument are allowed.
<item>The first argument passed to <tt/main()/ is the program name.
<item>A maximum number of 10 arguments (including the program name) are
supported.
</enum>
<sect1>Program return code<p>

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@ -2,9 +2,10 @@
<article>
<title>Commodore 610 specific information for cc65
<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org">
<date>2003-12-16
<title>Commodore 610-specific information for cc65
<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org"><newline>
<url url="mailto:greg.king5@verizon.net" name="Greg King">
<date>2004-04-02
<abstract>
An overview over the Commodore 610 runtime system as it is implemented for the
@ -19,11 +20,11 @@ cc65 C compiler.
<sect>Overview<p>
This file contains an overview of the CBM 610 runtime system as it comes with
the cc65 C compiler. It describes the memory layout, CBM 610 specific header
the cc65 C compiler. It describes the memory layout, CBM 610-specific header
files, available drivers, and any pitfalls specific to that platform.
Please note that CBM 610 specific functions are just mentioned here, they are
described in detail in the separate <htmlurl url="funcref.html" name="function
Please note that CBM 610-specific functions are just mentioned here, they are
described in detail in the separate <url url="funcref.html" name="function
reference">. Even functions marked as "platform dependent" may be available on
more than one platform. Please see the function reference for more
information.
@ -31,21 +32,22 @@ information.
In addition to the Commodore 610 (named B40 in the U.S.), several other
machines are supported by this cc65 target, since they have identical
hardware: The Commodore 620 and 630 (more memory, additional coprocessor
card), and the Commodore 710, 720 and 730 (same hardware in another case with
a builtin monitor).
card), and the Commodore 710, 720, and 730 (same hardware in another case with
a built-in monitor).
<sect>Binary format<p>
The standard binary output format generated by the linker for the Commodore
610 target is a machine language program with a one line BASIC stub, which
transfers control to the machine language running in bank 1. This means that a
program can be loaded as BASIC program and started with RUN. It is of course
possible to change this behaviour by using a modified startup file and linker
610 target is a machine language program with a one-line BASIC stub, which
transfers control to the machine language running in bank 1. That means that a
program can be loaded as a BASIC program, and started with RUN. It is, of course,
possible to change that behaviour by using a modified startup file and linker
config.
<sect>Memory layout<p>
cc65 generated programs for the Commodore 610 run in bank 1, the memory bank
@ -57,8 +59,8 @@ The default memory configuration for the CBM 610 allocates all memory between
&dollar;0002 and &dollar;FFF0 in bank 1 for the compiled program. Some space
in low memory is lost, because a separate hardware stack is set up in page 1,
and the kernal replacement functions need some more memory locations. A few
more bytes are lost in high memory, because the runtime sets up a CBM
compatible jump table at &dollar;FF81. The main startup code is located at
more bytes are lost in high memory, because the runtime sets up a CBM-compatible
jump table at &dollar;FF81. The main startup code is located at
&dollar;0400, so about 63K of the complete bank are actually usable for
applications.
@ -66,25 +68,26 @@ Special locations:
<descrip>
<tag/Stack/
The C runtime stack is located at &dollar;FF81 and growing downwards.
The C runtime stack is located at &dollar;FF81, and grows downwards.
<tag/Heap/
The C heap is located at the end of the program and grows towards the C
The C heap is located at the end of the program, and grows towards the C
runtime stack.
</descrip><p>
<sect>Platform specific header files<p>
<sect>Platform-specific header files<p>
Programs containing CBM 610 specific code may use the <tt/cbm610.h/ or
Programs containing CBM 610-specific code may use the <tt/cbm610.h/ or
<tt/cbm.h/ header files. Using the later may be an option when writing code
for more than one CBM platform, since it includes <tt/cbm610.h/ and declares
for more than one CBM platform, since it includes <tt/cbm610.h/, and declares
several functions common to all CBM platforms.
<sect1>CBM 610 specific functions<p>
The functions listed below are special for the CBM 610. See the <htmlurl
<sect1>CBM 610-specific functions<p>
The functions listed below are special for the CBM 610. See the <url
url="funcref.html" name="function reference"> for declaration and usage.
<itemize>
@ -95,10 +98,10 @@ url="funcref.html" name="function reference"> for declaration and usage.
</itemize>
<sect1>CBM specific functions<p>
<sect1>CBM-specific functions<p>
Some functions are available for all (or at least most) of the Commodore
machines. See the <htmlurl url="funcref.html" name="function reference"> for
machines. See the <url url="funcref.html" name="function reference"> for
declaration and usage.
@ -128,16 +131,15 @@ declaration and usage.
</itemize>
<sect1>Hardware access<p>
The following pseudo variables declared in the <tt/cbm610.h/ header file do
allow access to hardware located in the address space. Some variables are
structures, accessing the struct fields will access the chip registers.
structures; accessing the struct fields will access the chip registers.
<bf>Note:</bf> All I/O chips are located in the system bank (bank 15) and can
<bf>Note:</bf> All I/O chips are located in the system bank (bank 15); and can
therefore not be accessed like on other platforms. Please use one of the
<tt/peekbsys/, <tt/peekwsys/, <tt/pokebsys/ and <tt/pokewsys/ functions to
<tt/peekbsys/, <tt/peekwsys/, <tt/pokebsys/, and <tt/pokewsys/ functions to
access the I/O chips. Direct reads and writes to the structures named below
will <em>not</em> work!
@ -163,7 +165,7 @@ will <em>not</em> work!
declaration of the structure.
<tag><tt/TPI1, TPI2/</tag>
The two 6525 triport chips may be accessed by using this variable. See the
The two 6525 triport chips may be accessed by using these variables. See the
<tt/_6525.h/ header file located in the include directory for the
declaration of the structure.
@ -180,7 +182,7 @@ The names in the parentheses denote the symbols to be used for static linking of
No graphics drivers are currently available for the Commodore 610 (and since
the machine has no graphics capabilities, chances for a graphics driver aren't
really good:-).
really good :-).
<sect1>Extended memory drivers<p>
@ -194,9 +196,8 @@ really good:-).
<sect1>Joystick drivers<p>
The Commodore 610 is a business machine and doesn't have joystick ports. There
are no drivers for the non existing ports available.
The Commodore 610 is a business machine, and doesn't have joystick ports. There
are no drivers for the non-existing ports available.
<sect1>Mouse drivers<p>
@ -210,14 +211,15 @@ No mouse drivers are currently available for the Commodore 610.
<tag><tt/cbm610-std.ser (cbm610_std_ser)/</tag>
Driver for the 6551 ACIA chip built into the Commodore 610. Supports up to
19200 baud, hardware flow control (RTS/CTS) and interrupt driven receives.
Note that because of the peculiarities of the 6551 chip transmits are not
interrupt driven, and the transceiver blocks if the receiver asserts flow
19200 BPS, hardware flow control (RTS/CTS), and interrupt-driven receives.
Note that, because of the peculiarities of the 6551 chip, transmits are not
interrupt driven; and, the transceiver blocks if the receiver asserts flow
control because of a full buffer.
</descrip><p>
<sect>Limitations<label id="limitations"><p>
@ -227,27 +229,44 @@ Since the program runs in bank 1, and the kernal and all I/O chips are located
in bank 15, calling ROM routines or accessing hardware needs special code. The
cc65 runtime implements wrappers for all functions in the kernal jump table.
While this simplifies things, it should be noted that the wrappers do have
quite an impact on performance: A cross bank call has an extra 300&micro;s
quite an impact on performance: A cross-bank call has an extra 300&micro;s
penalty added by the wrapper.
<sect1>Interrupts<p>
Compiled programs contain an interrupt handler that runs in the program bank.
This has several advantages, one of them being performance (see cross bank
This has several advantages, one of them being performance (see cross-bank
call overhead mentioned above). However, this introduces one problem:
Interrupts are lost while the CPU executes code in the kernal bank. As a
result, the clock may go wrong and (worse) serial interrupts may get lost.
result, the clock may go wrong; and (worse), serial interrupts may get lost.
Since the cc65 runtime does only call the kernal for disk I/O, this means that
a program should not do file I/O while it depends on interrupts.
<sect>Other hints<p>
<sect1>Passing arguments to the program<p>
Command line argument passing is currently not supported for the Commodore
610.
Command-line arguments can be passed to <tt/main()/. Since that is not
supported directly by BASIC, the following syntax was chosen:
<tscreen><verb>
RUN:REM ARG1 " ARG2 IS QUOTED" ARG3 "" ARG5
</verb></tscreen>
<enum>
<item>Arguments are separated by spaces.
<item>Arguments may be quoted.
<item>Leading and trailing spaces around an argument are ignored. Spaces within
a quoted argument are allowed.
<item>The first argument passed to <tt/main()/ is the program name.
<item>A maximum number of 10 arguments (including the program name) are
supported.
</enum>
<sect1>Program return code<p>
@ -262,7 +281,7 @@ The runtime for the Commodore 610 uses routines marked as <tt/.INTERRUPTOR/
for interrupt handlers. Such routines must be written as simple machine
language subroutines and will be called automatically by the interrupt handler
code when they are linked into a program. See the discussion of the
<tt/.CONDES/ feature in the <htmlurl url="ca65.html" name="assembler manual">.
<tt/.CONDES/ feature in the <url url="ca65.html" name="assembler manual">.

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@ -1,24 +1,156 @@
; mainargs.s
;
; Ullrich von Bassewitz, 2003-03-07
; 2003-03-07, Ullrich von Bassewitz,
; based on code from Stefan A. Haubenthal, <polluks@web.de>
; 2005-02-26, Ullrich von Bassewitz
; 2014-04-02, Greg King
;
; 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:
;
; run
; run : rem
; run:rem arg1 " arg 2 is quoted " arg3 "" arg5
;
; "run" and "rem" are entokenned; the args. are not. Leading and trailing
; spaces outside of quotes are ignored.
;
; 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
.import sys_bank, restore_bank
.import sysp0:zp, ptr1:zp
.include "cbm510.inc"
.macpack generic
;---------------------------------------------------------------------------
MAXARGS = 10 ; Maximum number of arguments allowed
REM = $8f ; BASIC token-code
NAME_LEN = 16 ; maximum length of command-name
; Get possible command-line arguments. Goes into the special INIT segment,
; which may be reused after the startup code is run
; which may be reused after the startup code is run.
;
.segment "INIT"
.proc initmainargs
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.
;
jsr sys_bank
ldy #FNAM
lda (sysp0),y ; Get file-name pointer from system bank
sta ptr1
iny
lda (sysp0),y
sta ptr1+1
iny ; FNAM_BANK
lda (sysp0),y
tax
ldy #FNAM_LEN
lda (sysp0),y
tay
stx IndReg ; Look for name in correct bank
cpy #NAME_LEN + 1
blt L1
ldy #NAME_LEN - 1 ; limit the length
L0: lda (ptr1),y
sta name,y
L1: dey
bpl L0
jsr restore_bank
inc __argc ; argc always is equal to at least 1
; Find a "rem" token.
;
ldx #0
L2: lda BASIC_BUF,x
bze done ; no "rem," no args.
inx
cmp #REM
bne L2
ldy #1 * 2
; Find the next argument.
;
next: lda BASIC_BUF,x
bze done ; End of line reached
inx
cmp #' ' ; Skip leading spaces
beq next ;
; Found start of next argument. We've incremented the pointer in X already, so
; it points to the second character of the argument. That is useful because we
; will check now for a quoted argument; in which case, we will have to skip that
; first character.
;
found: cmp #'"' ; Is the argument quoted?
beq setterm ; Jump if so
dex ; Reset pointer to first argument character
lda #' ' ; A space ends the argument
setterm:sta term ; Set end-of-argument marker
; Now, store a pointer to the argument into the next slot.
;
txa ; Get low byte
add #<BASIC_BUF
sta argv,y ; argv[y]= &arg
lda #>0
adc #>BASIC_BUF
sta argv+1,y
iny
iny
inc __argc ; Found another arg
; Search for the end of the argument.
;
argloop:lda BASIC_BUF,x
bze done
inx
cmp term
bne argloop
; We've found the end of the argument. X points one character behind it, and
; A contains the terminating character. To make the argument a valid C string,
; replace the terminating character by a zero.
;
lda #0
sta BASIC_BUF-1,x
; Check if the maximum number of command-line arguments is reached. If not,
; parse the next one.
;
lda __argc ; Get low byte of argument count
cmp #MAXARGS ; Maximum number of arguments reached?
blt next ; Parse next one if not
; (The last vector in argv[] already is NULL.)
;
done: lda #<argv
ldx #>argv
sta __argv
stx __argv + 1
rts
.endproc
; These arrays are zeroed before initmainargs is called.
; char name[16+1];
; char* argv[MAXARGS+1]={name};
;
.bss
term: .res 1
name: .res NAME_LEN + 1
.data
argv: .addr name
.res MAXARGS * 2, 0

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@ -1,24 +1,156 @@
; mainargs.s
;
; Ullrich von Bassewitz, 2003-03-07
; 2003-03-07, Ullrich von Bassewitz,
; based on code from Stefan A. Haubenthal, <polluks@web.de>
; 2005-02-26, Ullrich von Bassewitz
; 2014-04-02, Greg King
;
; 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:
;
; run
; run : rem
; run:rem arg1 " arg 2 is quoted " arg3 "" arg5
;
; "run" and "rem" are entokenned; the args. are not. Leading and trailing
; spaces outside of quotes are ignored.
;
; 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
.import sys_bank, restore_bank
.import sysp0:zp, ptr1:zp
.include "cbm610.inc"
.macpack generic
;---------------------------------------------------------------------------
MAXARGS = 10 ; Maximum number of arguments allowed
REM = $8f ; BASIC token-code
NAME_LEN = 16 ; maximum length of command-name
; Get possible command-line arguments. Goes into the special INIT segment,
; which may be reused after the startup code is run
; which may be reused after the startup code is run.
;
.segment "INIT"
.proc initmainargs
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.
;
jsr sys_bank
ldy #FNAM
lda (sysp0),y ; Get file-name pointer from system bank
sta ptr1
iny
lda (sysp0),y
sta ptr1+1
iny ; FNAM_BANK
lda (sysp0),y
tax
ldy #FNAM_LEN
lda (sysp0),y
tay
stx IndReg ; Look for name in correct bank
cpy #NAME_LEN + 1
blt L1
ldy #NAME_LEN - 1 ; limit the length
L0: lda (ptr1),y
sta name,y
L1: dey
bpl L0
jsr restore_bank
inc __argc ; argc always is equal to at least 1
; Find a "rem" token.
;
ldx #0
L2: lda BASIC_BUF,x
bze done ; no "rem," no args.
inx
cmp #REM
bne L2
ldy #1 * 2
; Find the next argument.
;
next: lda BASIC_BUF,x
bze done ; End of line reached
inx
cmp #' ' ; Skip leading spaces
beq next ;
; Found start of next argument. We've incremented the pointer in X already, so
; it points to the second character of the argument. That is useful because we
; will check now for a quoted argument; in which case, we will have to skip that
; first character.
;
found: cmp #'"' ; Is the argument quoted?
beq setterm ; Jump if so
dex ; Reset pointer to first argument character
lda #' ' ; A space ends the argument
setterm:sta term ; Set end-of-argument marker
; Now, store a pointer to the argument into the next slot.
;
txa ; Get low byte
add #<BASIC_BUF
sta argv,y ; argv[y]= &arg
lda #>0
adc #>BASIC_BUF
sta argv+1,y
iny
iny
inc __argc ; Found another arg
; Search for the end of the argument.
;
argloop:lda BASIC_BUF,x
bze done
inx
cmp term
bne argloop
; We've found the end of the argument. X points one character behind it, and
; A contains the terminating character. To make the argument a valid C string,
; replace the terminating character by a zero.
;
lda #0
sta BASIC_BUF-1,x
; Check if the maximum number of command-line arguments is reached. If not,
; parse the next one.
;
lda __argc ; Get low byte of argument count
cmp #MAXARGS ; Maximum number of arguments reached?
blt next ; Parse next one if not
; (The last vector in argv[] already is NULL.)
;
done: lda #<argv
ldx #>argv
sta __argv
stx __argv + 1
rts
.endproc
; These arrays are zeroed before initmainargs is called.
; char name[16+1];
; char* argv[MAXARGS+1]={name};
;
.bss
term: .res 1
name: .res NAME_LEN + 1
.data
argv: .addr name
.res MAXARGS * 2, 0