From cdade1790575d33a14a4d5a18743797b7e7da57a Mon Sep 17 00:00:00 2001
From: Hayodea Hekol <hayodea@protonmail.com>
Date: Sat, 1 Nov 2025 00:06:42 -0400
Subject: [PATCH] Add SpMcRingBuffer to base class StimulusBuffer

This will hopefully genericise the interface for Stimbuffs.
---
 include/user/sequenceLock.h                     |  8 ++++++++
 include/user/spMcRingBuffer.h                   | 11 +++++++----
 include/user/stimulusBuffer.h                   |  5 +++++
 stimBuffApis/livoxGen1/pcloudStimulusBuffer.cpp | 10 +++++++++-
 4 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/include/user/sequenceLock.h b/include/user/sequenceLock.h
index b8808ef..118e541 100644
--- a/include/user/sequenceLock.h
+++ b/include/user/sequenceLock.h
@@ -20,6 +20,14 @@ public:
 	: sequenceNo(0)
 	{}
 
+	~SequenceLock() = default;
+
+	// Non-copyable, non-movable (std::atomic is neither copyable nor movable)
+	SequenceLock(const SequenceLock&) = delete;
+	SequenceLock& operator=(const SequenceLock&) = delete;
+	SequenceLock(SequenceLock&&) = delete;
+	SequenceLock& operator=(SequenceLock&&) = delete;
+
 	/* Atomically increments sequenceNo and issues a release barrier.
 	 * Makes the sequence number odd, indicating a write is in progress.
 	 */
diff --git a/include/user/spMcRingBuffer.h b/include/user/spMcRingBuffer.h
index 34f6a2a..e37fcc2 100644
--- a/include/user/spMcRingBuffer.h
+++ b/include/user/spMcRingBuffer.h
@@ -2,6 +2,7 @@
 #define _SP_MC_RING_BUFFER_H
 
 #include <vector>
+#include <memory>
 #include <cstddef>
 #include <stdexcept>
 #include <algorithm>
@@ -44,8 +45,8 @@ public:
 	 * locks array.
 	 */
 	explicit SpMcRingBuffer(
-		const InputEngineConstraints& constraints_,
-		size_t nSlots_)
+		size_t nSlots_,
+		const InputEngineConstraints& constraints_)
 	: nSlots(nSlots_), strideNBytes(0), bufferNBytes(0),
 	  constraints(constraints_)
 	{
@@ -59,7 +60,8 @@ public:
 		// Allocate data buffer: bufferNBytes (aligned up to alignment)
 		data.resize(bufferNBytes);
 		// Initialize sequence locks array: one lock per slot
-		sequenceLocks.resize(nSlots);
+		// Use unique_ptr array since SequenceLock is not copyable or movable
+		sequenceLocks = std::make_unique<SequenceLock[]>(nSlots);
 	}
 
 	~SpMcRingBuffer() = default;
@@ -121,7 +123,8 @@ private:
 	std::vector<uint8_t> data;
 
 	// Sequence locks array: one lock per slot
-	std::vector<SequenceLock> sequenceLocks;
+	// Use unique_ptr array since SequenceLock is not copyable or movable
+	std::unique_ptr<SequenceLock[]> sequenceLocks;
 
 public:
 	// Layout/invariants
diff --git a/include/user/stimulusBuffer.h b/include/user/stimulusBuffer.h
index 286a381..f648b97 100644
--- a/include/user/stimulusBuffer.h
+++ b/include/user/stimulusBuffer.h
@@ -13,6 +13,7 @@
 #include <boost/asio/deadline_timer.hpp>
 #include <spinLock.h>
 #include <asynchronousBridge.h>
+#include <user/spMcRingBuffer.h>
 #include "stimFrame.h"
 #include "deviceAttachmentSpec.h"
 
@@ -48,8 +49,11 @@ public:
 public:
 	explicit StimulusBuffer(
 		const device::DeviceAttachmentSpec& deviceAttachmentSpec,
+		size_t nSlots,
+		const SpMcRingBuffer::InputEngineConstraints& ringBufferConstraints,
 		boost::asio::io_service& ioService)
 	: deviceAttachmentSpec(deviceAttachmentSpec),
+	ringBuffer(nSlots, ringBufferConstraints),
 	ioService(ioService),
 	shouldContinue(false), timer(ioService)
 	{}
@@ -89,6 +93,7 @@ public:
 
 protected:
 	SpinLock frameAssemblyRateLimiter;
+	SpMcRingBuffer ringBuffer;
 
 private:
 	boost::asio::io_service& ioService;
diff --git a/stimBuffApis/livoxGen1/pcloudStimulusBuffer.cpp b/stimBuffApis/livoxGen1/pcloudStimulusBuffer.cpp
index 2a16e17..9b9199d 100644
--- a/stimBuffApis/livoxGen1/pcloudStimulusBuffer.cpp
+++ b/stimBuffApis/livoxGen1/pcloudStimulusBuffer.cpp
@@ -1,5 +1,8 @@
+#include <config.h>
 #include <opts.h>
 #include <algorithm>
+#include <unistd.h>
+#include <user/spMcRingBuffer.h>
 #include <componentThread.h>
 #include "pcloudStimulusBuffer.h"
 
@@ -11,7 +14,12 @@ PcloudStimulusBuffer::PcloudStimulusBuffer(
 	std::shared_ptr<livoxProto1::Device> &device,
 	const PcloudFormatDesc& formatDesc,
 	size_t nDgramsPerStagingBufferFrame)
-:	StimulusBuffer(deviceAttachmentSpec, device->componentThread->getIoService()),
+:	StimulusBuffer(
+		deviceAttachmentSpec,
+		static_cast<size_t>((1000 * 30) / CONFIG_STIMBUFF_FRAME_PERIOD_MS),
+		SpMcRingBuffer::InputEngineConstraints(
+			static_cast<size_t>(sysconf(_SC_PAGE_SIZE)), 4),
+		device->componentThread->getIoService()),
 deviceAttachmentSpec(deviceAttachmentSpec), device(device),
 formatDesc(formatDesc), stagingBuffer(
 	StagingBuffer::InputEngineConstraints::ioUringConstraints,