From f86d40241e17600dc9874785cabfc14fbdfd1be5 Mon Sep 17 00:00:00 2001
From: Drath Vader <drathvader@wp.pl>
Date: Thu, 27 Nov 2025 15:23:17 +0100
Subject: [PATCH] i was never checking the return value of write

---
 include/LCDDisplay.hpp |  2 +-
 src/LCDDisplay.cpp     | 20 +++++++++++---------
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/include/LCDDisplay.hpp b/include/LCDDisplay.hpp
index c891793..7c7937d 100644
--- a/include/LCDDisplay.hpp
+++ b/include/LCDDisplay.hpp
@@ -15,7 +15,7 @@ class LCDDisplay {
     char writebuf[LCD_LINES * LCD_COLS + 8];                       // 4x40 chars + 2x4 setcursor commands
     static constexpr bool dualDisp = (LCD_LINES * LCD_COLS > 80);  // is it dual display device or not, evauluated from the size at compile time
 
-    void open();
+    void open(bool reopen = false);
     void write(const uint8_t* cmdbuf, uint8_t len);
     void close();
 
diff --git a/src/LCDDisplay.cpp b/src/LCDDisplay.cpp
index 132fbdb..580f897 100644
--- a/src/LCDDisplay.cpp
+++ b/src/LCDDisplay.cpp
@@ -33,17 +33,15 @@ LCDDisplay::LCDDisplay(std::string dev, uint32_t baud) {
 
     // clear display and set cursor home
     this->clear();
-    this->close();
-    log(LOG::INF, "LCDDisplay", "Opened LCD port at \"{}\"", _dev);
 }
 
 LCDDisplay::~LCDDisplay() {
     this->close();
-    log(LOG::INF, "LCDDisplay", "Closed LCD port");
 }
 
-void LCDDisplay::open() {
-    if (_lcd < 0)
+void LCDDisplay::open(bool reopen) {
+    log(LOG::INF, "LCDDisplay", "Opening serial port at \"{}\"", _dev);
+    if (_lcd < 0 || reopen)
         _lcd = ::open(_dev.c_str(), O_RDWR | O_NOCTTY | O_NONBLOCK); // ::open calls the global open() instead of LCDDisplay::open()
     if (_lcd < 0) {
         log(LOG::ERR, "LCDDisplay", "Error opening serial port \"{}\"", _dev);  // err
@@ -52,15 +50,19 @@ void LCDDisplay::open() {
 }
 
 void LCDDisplay::close() {
-    if (_lcd >= 0)
+    if (_lcd >= 0) {
         ::close(_lcd);
+        log(LOG::INF, "LCDDisplay", "Closed LCD port");
+    }
     _lcd = -1;
 }
 
 void LCDDisplay::write(const uint8_t* cmdbuf, uint8_t len) {
-    this->open();
-    ::write(_lcd, cmdbuf, len);
-    this->close();
+    int rc = ::write(_lcd, cmdbuf, len);
+    if(rc < 0) {
+        log(LOG::ERR, "LCDDisplay::write", "failed to execute ::write, lost access to port?");
+        this->open(true);
+    }
 }
 
 void LCDDisplay::clear() {