From 6a89e22a29865a16818efab5b0927c4550ab3639 Mon Sep 17 00:00:00 2001
From: pythonology <pythonology@gmail.com>
Date: Sat, 15 Jun 2019 23:12:04 -0400
Subject: [PATCH] serialization: Fix incorrect byte alignment when...

...dynamic properties contain object pointers that end with bit-based
properties.
---
 include/ki/util/BitStream.h            |  5 +++++
 src/serialization/BinarySerializer.cpp | 20 ++++++++++++++------
 src/util/BitStream.cpp                 |  5 +++++
 3 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/include/ki/util/BitStream.h b/include/ki/util/BitStream.h
index 8d6ac5a..5deb841 100644
--- a/include/ki/util/BitStream.h
+++ b/include/ki/util/BitStream.h
@@ -278,6 +278,11 @@ namespace ki
 		 */
 		void seek(stream_pos position, bool expand = true);
 
+		/**
+		* Realigns the position of the stream so that it lies directly on a byte.
+		*/
+		void realign();
+
 		/**
 		 * @returns The current size of the internal buffer.
 		 */
diff --git a/src/serialization/BinarySerializer.cpp b/src/serialization/BinarySerializer.cpp
index a3ecd1d..dad2bc7 100644
--- a/src/serialization/BinarySerializer.cpp
+++ b/src/serialization/BinarySerializer.cpp
@@ -163,9 +163,9 @@ namespace serialization
 
 	void BinarySerializer::save_property(const pclass::IProperty &prop, BitStream &stream) const
 	{
-		// Determine if we need to re-align the stream so that our position lies on a byte
-		if (prop.get_type().is_byte_based() || prop.is_dynamic() || m_is_file)
-			stream.seek(BitStream::stream_pos(stream.tell().as_bytes(), 0));
+		// Realign the stream if we're going to write a prefix for this property
+		if (prop.is_dynamic() || m_is_file)
+			stream.realign();
 
 		// Remember where we started writing the property data
 		const auto start_pos = stream.tell();
@@ -196,6 +196,10 @@ namespace serialization
 
 		for (auto i = 0; i < prop.get_element_count(); ++i)
 		{
+			// Realign the stream if this property works in bytes
+			if (prop.get_type().is_byte_based())
+				stream.realign();
+
 			if (prop.is_pointer()
 				&& prop.get_type().get_kind() == pclass::Type::Kind::CLASS)
 			{
@@ -369,9 +373,9 @@ namespace serialization
 
 	void BinarySerializer::load_property(pclass::IProperty &prop, BitStream &stream) const
 	{
-		// Determine if we need to re-align the stream so that our position lies on a byte
-		if (prop.get_type().is_byte_based() || prop.is_dynamic())
-			stream.seek(BitStream::stream_pos(stream.tell().as_bytes(), 0));
+		// Re-align the stream if we're going to read a prefix for this property
+		if (prop.is_dynamic())
+			stream.realign();
 
 		// If the property is dynamic, we need to load the element count
 		if (prop.is_dynamic())
@@ -393,6 +397,10 @@ namespace serialization
 
 		for (auto i = 0; i < prop.get_element_count(); ++i)
 		{
+			// Realign the stream if this property works in bytes
+			if (prop.get_type().is_byte_based())
+				stream.realign();
+
 			if (prop.is_pointer() &&
 				prop.get_type().get_kind() == pclass::Type::Kind::CLASS)
 			{
diff --git a/src/util/BitStream.cpp b/src/util/BitStream.cpp
index 9f8f78e..112b733 100644
--- a/src/util/BitStream.cpp
+++ b/src/util/BitStream.cpp
@@ -386,6 +386,11 @@ namespace ki
 		m_position = position;
 	}
 
+	void realign()
+	{
+		seek(stream_pos(tell().as_bytes(), 0), false);
+	}
+
 	std::size_t BitStream::capacity() const
 	{
 		return m_buffer->size();