From 8f35004a017b8a3a2af7fb0a739723957971e9f5 Mon Sep 17 00:00:00 2001
From: Cory McWilliams <cory@unprompted.com>
Date: Sun, 6 Feb 2022 00:46:34 +0000
Subject: [PATCH] Reduce packetstream allocation frequency.

git-svn-id: https://www.unprompted.com/svn/projects/tildefriends/trunk@3825 ed5197a5-7fde-0310-b194-c3ffbd925b24
---
 src/packetstream.c | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/src/packetstream.c b/src/packetstream.c
index d45ce030..0f15b32d 100644
--- a/src/packetstream.c
+++ b/src/packetstream.c
@@ -12,6 +12,7 @@ typedef struct _tf_packetstream_t {
 	uv_pipe_t stream;
 	char* buffer;
 	size_t buffer_size;
+	size_t buffer_capacity;
 	bool destroyed;
 } tf_packetstream_t;
 
@@ -27,6 +28,11 @@ void tf_packetstream_destroy(tf_packetstream_t* stream)
 	stream->onreceive = NULL;
 	stream->onreceive_user_data = NULL;
 	stream->destroyed = true;
+	if (stream->buffer)
+	{
+		free(stream->buffer);
+		stream->buffer = NULL;
+	}
 	if (stream->stream.data)
 	{
 		tf_packetstream_close(stream);
@@ -61,7 +67,6 @@ static void _packetstream_process_messages(tf_packetstream_t* stream)
 			size_t consumed = sizeof(length) + sizeof(packet_type) + length;
 			memmove(stream->buffer, stream->buffer + consumed, stream->buffer_size - consumed);
 			stream->buffer_size -= consumed;
-			stream->buffer = realloc(stream->buffer, stream->buffer_size);
 		}
 		else
 		{
@@ -77,11 +82,23 @@ static void _packetstream_on_read(uv_stream_t* handle, ssize_t count, const uv_b
 	{
 		if (count > 0)
 		{
-			char* new_buffer = realloc(stream->buffer, stream->buffer_size + count);
-			if (new_buffer)
+			char* write_buffer = stream->buffer;
+			if (stream->buffer_size + count > stream->buffer_capacity)
 			{
-				memcpy(new_buffer + stream->buffer_size, buffer->base, count);
-				stream->buffer = new_buffer;
+				if (!stream->buffer_capacity)
+				{
+					stream->buffer_capacity = 256;
+				}
+				while (stream->buffer_capacity < stream->buffer_size + count)
+				{
+					stream->buffer_capacity *= 2;
+				}
+				write_buffer = realloc(write_buffer, stream->buffer_capacity);
+			}
+			if (write_buffer)
+			{
+				memcpy(write_buffer + stream->buffer_size, buffer->base, count);
+				stream->buffer = write_buffer;
 				stream->buffer_size += count;
 			}
 			_packetstream_process_messages(stream);
@@ -133,6 +150,11 @@ static void _tf_packetstream_handle_closed(uv_handle_t* handle)
 {
 	tf_packetstream_t* packetstream = handle->data;
 	handle->data = NULL;
+	if (packetstream->buffer)
+	{
+		free(packetstream->buffer);
+		packetstream->buffer = NULL;
+	}
 	if (packetstream->destroyed)
 	{
 		free(packetstream);