From 9e272295491ee91add707566ed5758208f65b7e3 Mon Sep 17 00:00:00 2001
From: Julian Oes <julian@oes.ch>
Date: Wed, 1 Mar 2023 14:35:59 +1300
Subject: [PATCH] unicore: fix reset after one message

Signed-off-by: Julian Oes <julian@oes.ch>
---
 gps-parser-test.cpp | 22 ++++++++++++++++++++++
 src/unicore.cpp     | 16 ++++++++++++----
 src/unicore.h       |  3 +--
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/gps-parser-test.cpp b/gps-parser-test.cpp
index 61723b6..5d94f83 100644
--- a/gps-parser-test.cpp
+++ b/gps-parser-test.cpp
@@ -91,6 +91,27 @@ void test_uniheadinga()
 	assert(false);
 }
 
+void test_uniheadinga_twice()
+{
+	const char str[] =
+		"#UNIHEADINGA,89,GPS,FINE,2251,168052600,0,0,18,11;SOL_COMPUTED,NARROW_INT,0.3718,67.0255,-0.7974,0.0000,0.8065,3.3818,\"999\",31,21,21,18,3,01,3,f3*ece5bb07"
+		"#UNIHEADINGA,88,GPS,FINE,2251,175391000,0,0,18,13;SOL_COMPUTED,NARROW_INT,0.3500,88.4714,-1.5969,0.0000,1.0175,2.8484,\"999\",28,18,18,12,3,01,3,f3*2888f737";
+
+	UnicoreParser unicore_parser;
+
+	unsigned num_parsed = 0;
+
+	for (unsigned i = 0; i < sizeof(str); ++i) {
+		auto result = unicore_parser.parseChar(str[i]);
+
+		if (result == UnicoreParser::Result::GotHeading) {
+			++num_parsed;
+		}
+	}
+
+	assert(num_parsed == 2);
+}
+
 void test_unicore()
 {
 	test_empty();
@@ -98,6 +119,7 @@ void test_unicore()
 	test_too_long();
 	test_uniheadinga_wrong_crc();
 	test_uniheadinga();
+	test_uniheadinga_twice();
 }
 
 int main(int, char **)
diff --git a/src/unicore.cpp b/src/unicore.cpp
index 1e4fa3a..c7da300 100644
--- a/src/unicore.cpp
+++ b/src/unicore.cpp
@@ -43,8 +43,6 @@ UnicoreParser::Result UnicoreParser::parseChar(char c)
 	case State::Uninit:
 		if (c == '#') {
 			_state = State::GotHashtag;
-			_buffer_pos = 0;
-			_buffer_crc_pos = 0;
 		}
 
 		break;
@@ -58,7 +56,7 @@ UnicoreParser::Result UnicoreParser::parseChar(char c)
 
 		} else {
 			if (_buffer_pos >= sizeof(_buffer)) {
-				_state = State::Uninit;
+				reset();
 				return Result::None;
 			}
 
@@ -70,7 +68,7 @@ UnicoreParser::Result UnicoreParser::parseChar(char c)
 	case State::GotStar:
 		_buffer_crc[_buffer_crc_pos++] = c;
 
-		if (_buffer_crc_pos == 8) {
+		if (_buffer_crc_pos >= 8) {
 
 			// Make sure the CRC buffer is zero terminated.
 			_buffer_crc[_buffer_crc_pos] = '\0';
@@ -81,13 +79,16 @@ UnicoreParser::Result UnicoreParser::parseChar(char c)
 
 			if (isHeading()) {
 				if (extractHeading()) {
+					reset();
 					return Result::GotHeading;
 
 				} else {
+					reset();
 					return Result::WrongStructure;
 				}
 
 			} else {
+				reset();
 				return Result::UnknownSentence;
 			}
 		}
@@ -98,6 +99,13 @@ UnicoreParser::Result UnicoreParser::parseChar(char c)
 	return Result::None;
 }
 
+void UnicoreParser::reset()
+{
+	_state = State::Uninit;
+	_buffer_pos = 0;
+	_buffer_crc_pos = 0;
+}
+
 bool UnicoreParser::crcCorrect() const
 {
 	const uint32_t crc_calculated = calculateBlockCRC32(_buffer_pos, (uint8_t *)_buffer, 0);
diff --git a/src/unicore.h b/src/unicore.h
index 187b75d..febefbe 100644
--- a/src/unicore.h
+++ b/src/unicore.h
@@ -61,12 +61,11 @@ class UnicoreParser
 
 
 private:
+	void reset();
 	bool crcCorrect() const;
 	bool isHeading() const;
 	bool extractHeading();
 
-
-
 	// We have seen buffers with 154 bytes.
 	char _buffer[256];
 	unsigned _buffer_pos {0};