From 3e0e546d5a89bca60452703def7ede8c0c8d85ef Mon Sep 17 00:00:00 2001
From: Shuhei Takahashi <nya@google.com>
Date: Sat, 16 Apr 2022 10:17:40 +0900
Subject: [PATCH 1/2] Fix line-oriented callbacks

stdoutcb/stderrcb assume that an input string is a single line, but
in fact it can contain multiple lines, or even be a part of a line.

One of the consequence is that cocopa fails to parse compiler output
when it contains long lines (#1275).

This patch fixes the issue by introducing a buffer to accumulate
received data before passing them to callbacks.

Fixes #1275.
---
 src/arduino/arduino.ts | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/src/arduino/arduino.ts b/src/arduino/arduino.ts
index 3de74779..391f6a51 100644
--- a/src/arduino/arduino.ts
+++ b/src/arduino/arduino.ts
@@ -746,7 +746,25 @@ export class ArduinoApp {
             }
             return ret;
         }
-        const stdoutcb = (line: string) => {
+
+        // Wrap line-oriented callbacks to accept arbitrary chunks of data.
+        const wrapLineCallback = (callback: (line: string) => void) => {
+            let buffer = "";
+            return (data: string) => {
+                buffer += data;
+                for (;;) {
+                    const pos = buffer.indexOf(os.EOL);
+                    if (pos < 0) {
+                        break;
+                    }
+                    const line = buffer.substring(0, pos + os.EOL.length);
+                    buffer = buffer.substring(pos + os.EOL.length);
+                    callback(line);
+                }
+            };
+        }
+
+        const stdoutcb = wrapLineCallback((line: string) => {
             if (cocopa.callback) {
                 cocopa.callback(line);
             }
@@ -758,8 +776,8 @@ export class ArduinoApp {
                     arduinoChannel.channel.append(line);
                 }
             }
-        }
-        const stderrcb = (line: string) => {
+        });
+        const stderrcb = wrapLineCallback((line: string) => {
             if (os.platform() === "win32") {
                 line = line.trim();
                 if (line.length <= 0) {
@@ -784,7 +802,7 @@ export class ArduinoApp {
                 }
             }
             arduinoChannel.channel.append(line);
-        }
+        });
 
         return await util.spawn(
             this._settings.commandPath,

From 81ba0abe09704ec0b75ea913fe3b9bf5182331ef Mon Sep 17 00:00:00 2001
From: Ben McMorran <bemcmorr@microsoft.com>
Date: Fri, 29 Apr 2022 14:18:48 -0700
Subject: [PATCH 2/2] Avoid n^2 runtime on long lines

---
 src/arduino/arduino.ts | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/arduino/arduino.ts b/src/arduino/arduino.ts
index 30f8ee7c..a6135133 100644
--- a/src/arduino/arduino.ts
+++ b/src/arduino/arduino.ts
@@ -756,15 +756,18 @@ export class ArduinoApp {
         // Wrap line-oriented callbacks to accept arbitrary chunks of data.
         const wrapLineCallback = (callback: (line: string) => void) => {
             let buffer = "";
+            let startIndex = 0;
             return (data: string) => {
                 buffer += data;
-                for (;;) {
-                    const pos = buffer.indexOf(os.EOL);
+                while (true) {
+                    const pos = buffer.indexOf(os.EOL, startIndex);
                     if (pos < 0) {
+                        startIndex = buffer.length;
                         break;
                     }
                     const line = buffer.substring(0, pos + os.EOL.length);
                     buffer = buffer.substring(pos + os.EOL.length);
+                    startIndex = 0;
                     callback(line);
                 }
             };