1 files changed, 148 insertions, 0 deletions
diff --git a/include/salticidae/buffer.h b/include/salticidae/buffer.h
new file mode 100644
index 0000000..3f415c9
--- /dev/null
+++ b/include/salticidae/buffer.h
@@ -0,0 +1,148 @@
+#ifndef _SALTICIDAE_BUFFER_H
+#define _SALTICIDAE_BUFFER_H
+
+#include <list>
+
+namespace salticidae {
+
+class SegBuffer {
+    public:
+    struct buffer_entry_t {
+        bytearray_t data;
+        bytearray_t::iterator offset;
+        buffer_entry_t(): offset(data.begin()) {}
+        buffer_entry_t(bytearray_t &&_data):
+            data(std::move(_data)), offset(data.begin()) {}
+
+        buffer_entry_t(buffer_entry_t &&other) {
+            size_t _offset = other.offset - other.data.begin();
+            data = std::move(other.data);
+            offset = data.begin() + _offset;
+        }
+
+        buffer_entry_t &operator=(buffer_entry_t &&other) {
+            size_t _offset = other.offset - other.data.begin();
+            data = std::move(other.data);
+            offset = data.begin() + _offset;
+            return *this;
+        }
+
+        buffer_entry_t(const buffer_entry_t &other): data(other.data) {
+            offset = data.begin() + (other.offset - other.data.begin());
+        }
+
+        size_t length() const { return data.end() - offset; }
+    };
+
+    private:
+    std::list<buffer_entry_t> buffer;
+    size_t _size;
+
+    public:
+    SegBuffer(): _size(0) {}
+    ~SegBuffer() { clear(); }
+
+    void swap(SegBuffer &other) {
+        std::swap(buffer, other.buffer);
+        std::swap(_size, other._size);
+    }
+
+    SegBuffer(const SegBuffer &other):
+        buffer(other.buffer), _size(other._size) {}
+
+    SegBuffer(SegBuffer &&other):
+        buffer(std::move(other.buffer)), _size(other._size) {
+        other._size = 0;
+    }
+
+    SegBuffer &operator=(SegBuffer &&other) {
+        if (this != &other)
+        {
+            SegBuffer tmp(std::move(other));
+            tmp.swap(*this);
+        }
+        return *this;
+    }
+ 
+    SegBuffer &operator=(const SegBuffer &other) {
+        if (this != &other)
+        {
+            SegBuffer tmp(other);
+            tmp.swap(*this);
+        }
+        return *this;
+    }
+
+    void rewind(bytearray_t &&data) {
+        _size += data.size();
+        buffer.push_front(buffer_entry_t(std::move(data)));
+    }
+  
+    void push(bytearray_t &&data) {
+        _size += data.size();
+        buffer.push_back(buffer_entry_t(std::move(data)));
+    }
+
+    bytearray_t move_pop() {
+        auto res = std::move(buffer.front().data);
+        buffer.pop_front();
+        _size -= res.size();
+        return std::move(res);
+    }
+    
+    bytearray_t pop(size_t len) {
+        bytearray_t res;
+        auto i = buffer.begin();
+        while (len && i != buffer.end())
+        {
+            size_t copy_len = std::min(i->length(), len);
+            res.insert(res.end(), i->offset, i->offset + copy_len);
+            i->offset += copy_len;
+            len -= copy_len;
+            if (i->offset == i->data.end())
+                i++;
+        }
+        buffer.erase(buffer.begin(), i);
+        _size -= res.size();
+        return std::move(res);
+    }
+    
+    size_t size() const { return _size; }
+    bool empty() const { return buffer.empty(); }
+    
+    void clear() {
+        buffer.clear();
+        _size = 0;
+    }
+};
+
+struct MPSCWriteBuffer {
+    using buffer_entry_t = SegBuffer::buffer_entry_t;
+    using queue_t = MPSCQueueEventDriven<buffer_entry_t>;
+    queue_t buffer;
+
+    MPSCWriteBuffer() {}
+
+    MPSCWriteBuffer(const SegBuffer &other) = delete;
+    MPSCWriteBuffer(SegBuffer &&other) = delete;
+
+    void rewind(bytearray_t &&data) {
+        buffer.rewind(buffer_entry_t(std::move(data)));
+    }
+  
+    void push(bytearray_t &&data) {
+        buffer.enqueue(buffer_entry_t(std::move(data)));
+    }
+
+    bytearray_t move_pop() {
+        buffer_entry_t res;
+        buffer.try_dequeue(res);
+        return std::move(res.data);
+    }
+    
+    queue_t &get_queue() { return buffer; }
+};
+
+}
+
+#endif