From 215d0d32b41c7f2d7eb9ca7faa1f75a4b0d24b78 Mon Sep 17 00:00:00 2001
From: gengshenghong <gengshenghong2007@126.com>
Date: Wed, 1 Jun 2022 16:18:22 +0800
Subject: [PATCH] allow to set rts/dtr/brk/cts/dsr seperately for windows

---
 src/serialport.cpp     | 36 +++++++++++++++++++++++++++++++-----
 src/serialport.h       |  6 ++++++
 src/serialport_win.cpp | 34 ++++++++++++++++++++++------------
 3 files changed, 59 insertions(+), 17 deletions(-)

diff --git a/src/serialport.cpp b/src/serialport.cpp
index c03f38f1..d2d4481f 100644
--- a/src/serialport.cpp
+++ b/src/serialport.cpp
@@ -32,6 +32,17 @@ double getDoubleFromObject(Napi::Object options, std::string key) {
   return getValueFromObject(options, key).ToNumber().DoubleValue();
 }
 
+bool hasKeyWithDefinedValue(Napi::Object options, std::string key) {
+  if ((options).Has(key)) {
+    Napi::Value val = getValueFromObject(options, key);
+    if (val.IsUndefined() || val.IsNull()) {
+      return false;
+    }
+    return true;
+  }
+  return false;
+}
+
 Napi::Value Open(const Napi::CallbackInfo& info) {
   Napi::Env env = info.Env();
   // path
@@ -184,11 +195,26 @@ Napi::Value Set(const Napi::CallbackInfo& info) {
 
   SetBaton* baton = new SetBaton(callback);
   baton->fd = fd;
-  baton->brk = getBoolFromObject(options, "brk");
-  baton->rts = getBoolFromObject(options, "rts");
-  baton->cts = getBoolFromObject(options, "cts");
-  baton->dtr = getBoolFromObject(options, "dtr");
-  baton->dsr = getBoolFromObject(options, "dsr");
+  if (hasKeyWithDefinedValue(options, "brk")) {
+    baton->brkToSet = true;
+    baton->brk = getBoolFromObject(options, "brk");
+  }
+  if (hasKeyWithDefinedValue(options, "rts")) {
+    baton->rtsToSet = true;
+    baton->rts = getBoolFromObject(options, "rts");
+  }
+  if (hasKeyWithDefinedValue(options, "cts")) {
+    baton->ctsToSet = true;
+    baton->cts = getBoolFromObject(options, "cts");
+  }
+  if (hasKeyWithDefinedValue(options, "dtr")) {
+    baton->dtrToSet = true;
+    baton->dtr = getBoolFromObject(options, "dtr");
+  }
+  if (hasKeyWithDefinedValue(options, "dsr")) {
+    baton->rtsToSet = true;
+    baton->dsr = getBoolFromObject(options, "dsr");
+  }
   baton->lowLatency = getBoolFromObject(options, "lowLatency");
 
   baton->Queue();
diff --git a/src/serialport.h b/src/serialport.h
index 6489b417..134385c5 100644
--- a/src/serialport.h
+++ b/src/serialport.h
@@ -118,6 +118,12 @@ struct SetBaton : public Napi::AsyncWorker {
   bool brk = false;
   bool lowLatency = false;
 
+  bool rtsToSet = false;
+  bool dtrToSet = false;
+  bool brkToSet = false;
+  bool ctsToSet = false;
+  bool dsrToSet = false;
+
   void Execute() override;
 
   void OnOK() override {
diff --git a/src/serialport_win.cpp b/src/serialport_win.cpp
index b11c07fc..d314167f 100644
--- a/src/serialport_win.cpp
+++ b/src/serialport_win.cpp
@@ -223,22 +223,32 @@ void ConnectionOptionsBaton::Execute() {
 }
 
 void SetBaton::Execute() {
-  if (rts) {
-    EscapeCommFunction(int2handle(fd), SETRTS);
-  } else {
-    EscapeCommFunction(int2handle(fd), CLRRTS);
+  if (rtsToSet) {
+    if (rts) {
+      EscapeCommFunction(int2handle(fd), SETRTS);
+    } else {
+      EscapeCommFunction(int2handle(fd), CLRRTS);
+    }
   }
 
-  if (dtr) {
-    EscapeCommFunction(int2handle(fd), SETDTR);
-  } else {
-    EscapeCommFunction(int2handle(fd), CLRDTR);
+  if (dtrToSet) {
+    if (dtr) {
+      EscapeCommFunction(int2handle(fd), SETDTR);
+    } else {
+      EscapeCommFunction(int2handle(fd), CLRDTR);
+    }
   }
 
-  if (brk) {
-    EscapeCommFunction(int2handle(fd), SETBREAK);
-  } else {
-    EscapeCommFunction(int2handle(fd), CLRBREAK);
+  if (brkToSet) {
+    if (brk) {
+      EscapeCommFunction(int2handle(fd), SETBREAK);
+    } else {
+      EscapeCommFunction(int2handle(fd), CLRBREAK);
+    }
+  }
+
+  if (!ctsToSet && !dsrToSet) {
+    return;
   }
 
   DWORD bits = 0;