From c811d5330c224d2d2c6022dc3fbde427fcf61829 Mon Sep 17 00:00:00 2001
From: Virgil Dupras <hsoft@hardcoded.net>
Date: Sat, 13 Jul 2019 22:09:17 -0400
Subject: [PATCH] apps/ed: add support for addr ranges

---
 apps/ed/cmd.asm  | 50 ++++++++++++++++++++++++++++++++++++++++--------
 apps/ed/main.asm | 18 +++++++++++++++--
 2 files changed, 58 insertions(+), 10 deletions(-)

diff --git a/apps/ed/cmd.asm b/apps/ed/cmd.asm
index 0a86045..9d3cc7d 100644
--- a/apps/ed/cmd.asm
+++ b/apps/ed/cmd.asm
@@ -26,9 +26,41 @@ cmdParse:
 	ld	a, (hl)
 	cp	'q'
 	jr	z, .quit
-	ld	(CMD_TYPE), a
 	ld	ix, CMD_ADDR1
-	jp	.readAddr
+	call	.readAddr
+	ret	nz
+	; Before we check for the existence of a second addr, let's set that
+	; second addr to the same value as the first. That's going to be its
+	; value if we have to ",".
+	ld	a, (ix)
+	ld	(CMD_ADDR2), a
+	ld	a, (ix+1)
+	ld	(CMD_ADDR2+1), a
+	ld	a, (ix+2)
+	ld	(CMD_ADDR2+2), a
+	ld	a, (hl)
+	cp	','
+	jr	nz, .noaddr2
+	inc	hl
+	ld	ix, CMD_ADDR2
+	call	.readAddr
+	ret	nz
+.noaddr2:
+	; We expect HL (rest of the cmdline) to be a null char or an accepted
+	; cmd, otherwise it's garbage
+	ld	a, (hl)
+	or	a
+	jr	z, .nullCmd
+	cp	'p'
+	jr	z, .okCmd
+	; unsupported cmd
+	ret			; Z unset
+.nullCmd:
+	ld	a, 'p'
+.okCmd:
+	ld	(CMD_TYPE), a
+	ret			; Z already set
+
 .quit:
 	; Z already set
 	ld	(CMD_TYPE), a
@@ -84,14 +116,10 @@ cmdParse:
 	ex	de, hl
 	pop	hl
 .end:
-	; We expect HL (rest of the cmdline) to be a null char, otherwise it's
-	; garbage
-	ld	a, (hl)
-	or	a
-	ret	nz
 	; we still have to save DE in memory
 	ld	(ix+1), e
 	ld	(ix+2), d
+	cp	a		; ensure Z
 	ret
 
 ; call parseDecimal and set HL to the character following the last digit
@@ -106,7 +134,8 @@ cmdParse:
 	jr	nc, .loop
 	; We're at the first non-digit char. Let's save it because we're going
 	; to temporarily replace it with a null.
-	ld	b, a
+	ld	b, (hl)		; refetch (HL), A has been mucked with in
+				; parseDecimalDigit
 	xor	a
 	ld	(hl), a
 	; Now, let's go back to the beginning of the string and parse it.
@@ -129,6 +158,11 @@ cmdAddr1:
 	ld	ix, CMD_ADDR1
 	ret
 
+; Make (IX) point to addr 2
+cmdAddr2:
+	ld	ix, CMD_ADDR2
+	ret
+
 ; Set A to CMD_TYPE
 cmdType:
 	ld	a, (CMD_TYPE)
diff --git a/apps/ed/main.asm b/apps/ed/main.asm
index 62d92f5..5f3ca6a 100644
--- a/apps/ed/main.asm
+++ b/apps/ed/main.asm
@@ -96,12 +96,25 @@ edMain:
 .doPrint:
 	call	cmdAddr1
 	call	edResolveAddr
+	ex	de, hl		; DE: addr1
+	call	cmdAddr2
+	call	edResolveAddr
 	ld	(ED_CURLINE), hl
+	ex	de, hl		; HL: addr1, DE: addr2
+	call	cpHLDE
+	jr	z, .doPrintLoop	; DE == HL, ok
+	jr	nc, .error	; DE < HL, not good
+.doPrintLoop:
+	push	hl
 	call	bufGetLine
 	jr	nz, .error
 	call	printstr
 	call	printcrlf
-	jr	.mainLoop
+	pop	hl
+	call	cpHLDE
+	jr	nc, .mainLoop
+	inc	hl
+	jr	.doPrintLoop
 .error:
 	ld	a, '?'
 	call	stdioPutC
@@ -116,13 +129,14 @@ edResolveAddr:
 	jr	z, .relative
 	; absolute
 	ld	l, (ix+1)
-	ld	a, l
 	ld	h, (ix+2)
 	ret
 .relative:
 	ld	hl, (ED_CURLINE)
+	push	de
 	ld	e, (ix+1)
 	ld	d, (ix+2)
 	add	hl, de
+	pop	de
 	ret