From 9b74cedb20beccd9b4f270f3c8ce6ba712e385a2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Sat, 24 Aug 2019 11:33:13 +0200
Subject: [PATCH] vt: clear CSI parameters lazily

The CLEAR action is so common, that explicitly clearing the entire
params array, which is kind of big, is too slow.

Clear it lazily instead. Meaning, we only set 'idx' (count) to 0 in
CLEAR. Then whenever we parse a parameter, clear the value and sub
parameters.
---
 vt.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/vt.c b/vt.c
index e227bef8..d83384df 100644
--- a/vt.c
+++ b/vt.c
@@ -858,7 +858,7 @@ action(struct terminal *term, enum action _action, uint8_t c)
         break;
 
     case ACTION_CLEAR:
-        memset(&term->vt.params, 0, sizeof(term->vt.params));
+        term->vt.params.idx = 0;
         term->vt.private[0] = 0;
         term->vt.private[1] = 0;
         term->vt.osc.idx = 0;
@@ -874,13 +874,21 @@ action(struct terminal *term, enum action _action, uint8_t c)
         break;
 
     case ACTION_PARAM:
-        if (term->vt.params.idx == 0)
+        if (term->vt.params.idx == 0) {
             term->vt.params.idx = 1;
+            term->vt.params.v[0].value = 0;
+            term->vt.params.v[0].sub.idx = 0;
+        }
 
         if (c == ';') {
             term->vt.params.idx++;
+            term->vt.params.v[term->vt.params.idx - 1].value = 0;
+            term->vt.params.v[term->vt.params.idx - 1].sub.idx = 0;
+            term->vt.params.v[term->vt.params.idx - 1].sub.value[0] = 0;
         } else if (c == ':') {
-            term->vt.params.v[term->vt.params.idx - 1].sub.idx++;
+            struct vt_param *param = &term->vt.params.v[term->vt.params.idx - 1];
+            param->sub.idx++;
+            param->sub.value[param->sub.idx] = 0;
         } else {
             assert(term->vt.params.idx >= 0);
             struct vt_param *param = &term->vt.params.v[term->vt.params.idx - 1];