From c3ad620ba890cbee3261c4aaf14b9de581f28d74 Mon Sep 17 00:00:00 2001
From: Valentin Lenhart <valentin.lenhart@posteo.de>
Date: Sun, 20 Oct 2019 20:25:48 +0200
Subject: [PATCH] parseArgs: return number of arguments

---
 apps/at28w/main.asm |  3 ++-
 apps/zasm/main.asm  |  3 ++-
 kernel/parse.asm    | 19 +++++++++++++++----
 kernel/shell.asm    |  4 ++--
 4 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/apps/at28w/main.asm b/apps/at28w/main.asm
index 62802e2..ab57c99 100644
--- a/apps/at28w/main.asm
+++ b/apps/at28w/main.asm
@@ -14,7 +14,8 @@ at28wMain:
 	ld	de, .argspecs
 	ld	ix, AT28W_MAXBYTES
 	call	parseArgs
-	jr	z, at28wInner
+	cp	0xff
+	jr	nz, at28wInner
 	; bad args
 	ld	a, SHELL_ERR_BAD_ARGS
 	ret
diff --git a/apps/zasm/main.asm b/apps/zasm/main.asm
index b69422b..e1630f8 100644
--- a/apps/zasm/main.asm
+++ b/apps/zasm/main.asm
@@ -27,7 +27,8 @@ zasmMain:
 	ld	de, .argspecs
 	ld	ix, ZASM_RAMSTART
 	call	parseArgs
-	jr	z, .goodargs
+	cp	0xff
+	jr	nz, .goodargs
 	; bad args
 	ld	hl, 0
 	ld	de, 0
diff --git a/kernel/parse.asm b/kernel/parse.asm
index 8f7397b..1254511 100644
--- a/kernel/parse.asm
+++ b/kernel/parse.asm
@@ -90,12 +90,13 @@ parseArgs:
 	ld	(ix+1), a
 	ld	(ix+2), a
 	ld	b, PARSE_ARG_MAXCOUNT
-.loop:
+
 	ld	a, (hl)
 	; is this the end of the line?
 	or	a		; cp 0
-	jr	z, .endofargs
+	jr	z, .noargs
 
+.loop:
 	; Get the specs
 	ld	a, (de)
 	bit	0, a		; do we have an arg?
@@ -108,6 +109,7 @@ parseArgs:
 	; it a day. Little endian, remember
 	ld	(ix), l
 	ld	(ix+1), h
+	dec b
 	jr	.success	; directly to success: skip endofargs checks
 
 .notAString:
@@ -134,6 +136,12 @@ parseArgs:
 	jr	nz, .error
 	inc	hl
 .nospacecheck:
+
+	ld	a, (hl)
+	; is this the end of the line?
+	or	a		; cp 0
+	jr	z, .endofargs
+
 	djnz	.loop
 	; If we get here, it means that our next char *has* to be a null char
 	ld	a, (hl)
@@ -142,6 +150,8 @@ parseArgs:
 	jr	.error
 
 .endofargs:
+    dec b
+.noargs:
 	; We encountered our null char. Let's verify that we either have no
 	; more args or that they are optional
 	ld	a, (de)
@@ -151,10 +161,11 @@ parseArgs:
 	jr	z, .error	; if unset, arg is not optional. error
 	; success
 .success:
-	xor	a
+	ld	a, PARSE_ARG_MAXCOUNT
+	sbc a, b
 	jr	.end
 .error:
-	inc	a
+	ld	a, 0xff
 .end:
 	pop	ix
 	pop	hl
diff --git a/kernel/shell.asm b/kernel/shell.asm
index 491260b..75f58ee 100644
--- a/kernel/shell.asm
+++ b/kernel/shell.asm
@@ -155,8 +155,8 @@ shellParse:
 	; We're ready to parse args
 	ld	ix, SHELL_CMD_ARGS
 	call	parseArgs
-	or	a		; cp 0
-	jr	nz, .parseerror
+	cp	0xff
+	jr	z, .parseerror
 
 	; Args parsed, now we can load the routine address and call it.
 	; let's have DE point to the jump line