Replace concurrentqueue with ringbuffer

communication/ringbuffer.cpp

@@ -0,0 +1,91 @@
+#include "icsneo/communication/ringbuffer.h"
+#include <stdexcept>
+
+namespace icsneo {
+    
+RingBuffer::RingBuffer(size_t bufferSize) : readCursor(0), writeCursor(0) {
+    // round the buffer size to the nearest power of 2
+    bufferSize = RoundUp(bufferSize);
+    mask = bufferSize - 1;
+    buf = new uint8_t[bufferSize];
+}
+
+RingBuffer::~RingBuffer() {
+    delete[] buf;
+    buf = nullptr;
+}
+
+const uint8_t& RingBuffer::operator[](size_t offset) const { 
+    return get(offset); 
+}
+
+size_t RingBuffer::size() const { 
+    // The values in the cursors are monotonic, i.e. they only ever increment. They can be considered to be the total number of elements ever written or read
+    auto currentWriteCursor = writeCursor.load(std::memory_order_relaxed);
+    auto currentReadCursor = readCursor.load(std::memory_order_relaxed);
+    // Using unmasked values, writeCursor is guaranteed to be >= readCursor. If they are equal that means the buffer is empty
+    return currentWriteCursor - currentReadCursor; 
+}
+
+void RingBuffer::pop_front() {
+    pop(1);
+}
+
+void RingBuffer::pop(size_t count) {
+    if (size() < count) {
+        throw std::runtime_error("RingBuffer: Underflow");
+    }
+    readCursor.fetch_add(count, std::memory_order_release);
+}
+
+const uint8_t& RingBuffer::get(size_t offset) const {
+    if (offset >= size()) {
+        throw std::runtime_error("RingBuffer: Index out of range");
+    }
+    auto currentReadCursor = readCursor.load(std::memory_order_acquire);
+    return *resolve(currentReadCursor, offset);
+}
+
+bool RingBuffer::write(const uint8_t* addr, size_t length) {    
+    const auto freeSpace = (capacity() - size());
+    if (length > freeSpace) {
+        return false;
+    }
+    auto currentWriteCursor = writeCursor.load(std::memory_order_relaxed);
+    auto spaceAtEnd = std::min(freeSpace, capacity() - (currentWriteCursor & mask)); // number of bytes from (masked) writeCursor to the end of the writable space (i.e. we reach the masked read cursor or the end of the buffer)
+    auto firstCopySize = std::min(spaceAtEnd, length);
+    (void)memcpy(resolve(currentWriteCursor, 0), addr, firstCopySize);
+    if (firstCopySize < length)
+    {
+        (void)memcpy(buf, &addr[firstCopySize], length - firstCopySize);
+    }
+
+    writeCursor.store(currentWriteCursor + length, std::memory_order_release);
+    return true;
+}
+
+bool RingBuffer::write(const std::vector<uint8_t>& source) {
+    return write(source.data(), source.size());
+}
+
+bool RingBuffer::read(uint8_t* dest, size_t startIndex, size_t length) const {
+    auto currentSize = size();
+    if ((startIndex >= currentSize) || ((startIndex + length) > size())) {
+        return false;
+    }
+    auto currentReadCursor = readCursor.load(std::memory_order_relaxed);
+    auto bytesAtEnd = std::min<size_t>(capacity() - ((currentReadCursor + startIndex) & mask), length);
+    const auto bytesAtStart = (length - bytesAtEnd);
+
+    (void)memcpy(dest, resolve(currentReadCursor, startIndex), bytesAtEnd);
+    if (bytesAtStart > 0) {
+        (void)memcpy(&dest[bytesAtEnd], buf, bytesAtStart);
+    }
+    return true;
+}
+
+void RingBuffer::clear() {
+    pop(size());
+}
+
+}