From a99833d6c5c1a25eba14985faae062349ac73952 Mon Sep 17 00:00:00 2001
From: Curtis McEnroe <june@causal.agency>
Date: Sat, 10 Aug 2019 20:52:15 -0400
Subject: Respect scroll region in DL and IL

---
 term.c | 54 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 28 insertions(+), 26 deletions(-)

diff --git a/term.c b/term.c
index c71d4dc..8c2ee9f 100644
--- a/term.c
+++ b/term.c
@@ -53,11 +53,11 @@ static void move(struct Cell *dst, struct Cell *src, uint len) {
 	memmove(dst, src, sizeof(*dst) * len);
 }
 
-static void scrollUp(struct Term *t, uint n) {
+static void scrollUp(struct Term *t, uint top, uint n) {
 	move(
-		cell(t, t->scroll.top, 0),
-		cell(t, t->scroll.top + n, 0),
-		t->cols * (1 + t->scroll.bot - t->scroll.top - n)
+		cell(t, top, 0),
+		cell(t, top + n, 0),
+		t->cols * (1 + t->scroll.bot - top - n)
 	);
 	erase(
 		t->style,
@@ -66,16 +66,16 @@ static void scrollUp(struct Term *t, uint n) {
 	);
 }
 
-static void scrollDown(struct Term *t, uint n) {
+static void scrollDown(struct Term *t, uint top, uint n) {
 	move(
-		cell(t, t->scroll.top + n, 0),
-		cell(t, t->scroll.top, 0),
-		t->cols * (1 + t->scroll.bot - t->scroll.top - n)
+		cell(t, top + n, 0),
+		cell(t, top, 0),
+		t->cols * (1 + t->scroll.bot - top - n)
 	);
 	erase(
 		t->style,
-		cell(t, t->scroll.top, 0),
-		cell(t, t->scroll.top + n - 1, t->cols - 1)
+		cell(t, top, 0),
+		cell(t, top + n - 1, t->cols - 1)
 	);
 }
 
@@ -174,43 +174,40 @@ ACTION(ech) {
 	erase(t->style, C(Y, X), C(Y, MIN(X + P(0, 1) - 1, R)));
 }
 
-ACTION(dl) {
-	uint n = MIN(P(0, 1), t->rows - Y);
-	move(C(Y, 0), C(Y + n, 0), t->cols * (t->rows - Y - n));
-	erase(t->style, C(t->rows - n, 0), C(B, R));
-}
 ACTION(dch) {
 	uint n = MIN(P(0, 1), t->cols - X);
 	move(C(Y, X), C(Y, X + n), t->cols - X - n);
 	erase(t->style, C(Y, t->cols - n), C(Y, R));
 }
-ACTION(il) {
-	uint n = MIN(P(0, 1), t->rows - Y);
-	move(C(Y + n, 0), C(Y, 0), t->cols * (t->rows - Y - n));
-	erase(t->style, C(Y, 0), C(Y + n - 1, R));
-}
 ACTION(ich) {
 	uint n = MIN(P(0, 1), t->cols - X);
 	move(C(Y, X + n), C(Y, X), t->cols - X - n);
 	erase(t->style, C(Y, X), C(Y, X + n - 1));
 }
 
+ACTION(dl) { scrollUp(t, Y, MIN(P(0, 1), t->scroll.bot - Y)); }
+ACTION(il) { scrollDown(t, Y, MIN(P(0, 1), t->scroll.bot - Y)); }
+
 ACTION(nl) {
 	if (Y == t->scroll.bot) {
-		scrollUp(t, 1);
+		scrollUp(t, t->scroll.top, 1);
 	} else {
 		Y = MIN(Y + 1, B);
 	}
 }
 ACTION(ri) {
 	if (Y == t->scroll.top) {
-		scrollDown(t, 1);
+		scrollDown(t, t->scroll.top, 1);
 	} else {
 		if (Y) Y--;
 	}
 }
-ACTION(su)  { scrollUp(t, MIN(P(0, 1), t->scroll.bot - t->scroll.top)); }
-ACTION(sd)  { scrollDown(t, MIN(P(0, 1), t->scroll.bot - t->scroll.top)); }
+ACTION(su) {
+	scrollUp(t, t->scroll.top, MIN(P(0, 1), t->scroll.bot - t->scroll.top));
+}
+ACTION(sd) {
+	scrollDown(t, t->scroll.top, MIN(P(0, 1), t->scroll.bot - t->scroll.top));
+}
 ACTION(decstbm) {
 	t->scroll.bot = MIN(P(1, t->rows) - 1, B);
 	t->scroll.top = MIN(P(0, 1) - 1, t->scroll.bot);
@@ -227,10 +224,15 @@ static void mode(struct Term *t, wchar_t ch) {
 	for (uint i = 0; i < t->param.n; ++i) {
 		if (t->param.q) {
 			switch (t->param.s[i]) {
-				break; case 1:  // ignore
+				break; case 1: // DECCKM
 				break; case DECAWM: mode |= Wrap;
+				break; case 12: // "Start Blinking Cursor"
 				break; case DECTCEM: mode |= Cursor;
-				break; default: unhandled("DECSET/DECRST %u", t->param.s[i]);
+				break; default: {
+					if (t->param.s[i] < 1000) {
+						unhandled("DECSET/DECRST %u", t->param.s[i]);
+					}
+				}
 			}
 		} else {
 			switch (t->param.s[i]) {
-- 
cgit 1.4.1