From 4d59ddc3db6d9382e61bc4492e51c63283174489 Mon Sep 17 00:00:00 2001
From: "Robin.Mueller" <robin.mueller.m@gmail.com>
Date: Thu, 4 Jun 2020 19:50:26 +0200
Subject: [PATCH] some fixes, check for preamble size

---
 serviceinterface/ServiceInterfaceBuffer.cpp | 15 ++++++++-------
 serviceinterface/ServiceInterfaceBuffer.h   |  9 +++++++--
 2 files changed, 15 insertions(+), 9 deletions(-)

diff --git a/serviceinterface/ServiceInterfaceBuffer.cpp b/serviceinterface/ServiceInterfaceBuffer.cpp
index f1332637..5c80862c 100644
--- a/serviceinterface/ServiceInterfaceBuffer.cpp
+++ b/serviceinterface/ServiceInterfaceBuffer.cpp
@@ -17,8 +17,8 @@ ServiceInterfaceBuffer::ServiceInterfaceBuffer(std::string setMessage,
 		// Set pointers if the stream is buffered.
 		setp( buf, buf + BUF_SIZE );
 	}
-	preamble.reserve(96);
-	preamble.resize(96);
+	preamble.reserve(MAX_PREAMBLE_SIZE);
+	preamble.resize(MAX_PREAMBLE_SIZE);
 }
 
 void ServiceInterfaceBuffer::putChars(char const* begin, char const* end) {
@@ -36,7 +36,6 @@ void ServiceInterfaceBuffer::putChars(char const* begin, char const* end) {
 		else {
 			printChar(begin, false);
 		}
-
 	}
 }
 
@@ -80,8 +79,6 @@ int ServiceInterfaceBuffer::sync(void) {
 
 	size_t preambleSize  = 0;
 	auto preamble = getPreamble(&preambleSize);
-	uint8_t debugArray[96];
-	memcpy(debugArray, preamble.data(), preambleSize);
 	// Write logMessage and time
 	this->putChars(preamble.data(), preamble.data() + preambleSize);
 	// Handle output
@@ -98,7 +95,6 @@ bool ServiceInterfaceBuffer::isBuffered() const {
 std::string ServiceInterfaceBuffer::getPreamble(size_t * preambleSize) {
 	Clock::TimeOfDay_t loggerTime;
 	Clock::getDateAndTime(&loggerTime);
-	std::string preamble (96, 0);
 	size_t currentSize = 0;
 	char* parsePosition = &preamble[0];
 	if(addCrToPreamble) {
@@ -113,7 +109,12 @@ std::string ServiceInterfaceBuffer::getPreamble(size_t * preambleSize) {
 					loggerTime.second,
 					loggerTime.usecond /1000);
 	if(charCount < 0) {
-		printf("ServiceInterfaceBuffer: Failure parsing preamble");
+		printf("ServiceInterfaceBuffer: Failure parsing preamble\r\n");
+		return "";
+	}
+	if(charCount > MAX_PREAMBLE_SIZE) {
+		printf("ServiceInterfaceBuffer: Char count too large for maximum "
+				"preamble size");
 		return "";
 	}
 	currentSize += charCount;
diff --git a/serviceinterface/ServiceInterfaceBuffer.h b/serviceinterface/ServiceInterfaceBuffer.h
index 00a8e74a..39ea25c2 100644
--- a/serviceinterface/ServiceInterfaceBuffer.h
+++ b/serviceinterface/ServiceInterfaceBuffer.h
@@ -20,6 +20,8 @@ class ServiceInterfaceBuffer:
         public std::streambuf {
 	friend class ServiceInterfaceStream;
 public:
+	static constexpr uint8_t MAX_PREAMBLE_SIZE = 40;
+
 	ServiceInterfaceBuffer(std::string setMessage, bool addCrToPreamble,
 			bool buffered, bool errStream, uint16_t port);
 
@@ -41,14 +43,17 @@ private:
 	std::string preamble;
 	// For EOF detection
 	typedef std::char_traits<char> Traits;
+
 	//! This is useful for some terminal programs which do not have
 	//! implicit carriage return with newline characters.
 	bool addCrToPreamble;
 
+	//! Specifies whether the stream operates in buffered or unbuffered mode.
+	bool buffered;
 	//! This specifies to print to stderr and work in unbuffered mode.
 	bool errStream;
-	bool buffered;
-	// Work in buffer mode. It is also possible to work without buffer.
+
+	//! Needed for buffered mode.
 	static size_t const BUF_SIZE = 128;
 	char buf[BUF_SIZE];