inital commit (message v3)

solanaceae/message3/file_w_file.hpp

@@ -0,0 +1,46 @@
+#pragma once
+
+#include "./file.hpp"
+
+#include <string_view>
+#include <fstream>
+
+struct FileWFile : public FileI {
+	std::ofstream _file;
+
+	FileWFile(std::string_view file_path, uint64_t file_size) : _file(static_cast<std::string>(file_path), std::ios::binary) {
+		_file_size = file_size;
+
+		if (!_file.is_open()) {
+			return; // TODO: error
+		}
+	}
+
+	virtual ~FileWFile(void) {}
+
+	bool isGood(void) override {
+		return _file.is_open() && _file.good();
+	}
+
+	// write only
+	std::vector<uint8_t> read(uint64_t, uint32_t) override { return {}; }
+
+	bool write(uint64_t pos, const std::vector<uint8_t>& data) override {
+		if (_file_size > 0 && pos >= _file_size) {
+			return false;
+		}
+
+		// if out-of-order, seek
+		if (_file.tellp() != int64_t(pos)) {
+			// TODO: error check
+			_file.seekp(pos);
+		}
+
+		_file.write(reinterpret_cast<const char*>(data.data()), data.size());
+
+		_bytes_written += data.size();
+
+		return _file.good();
+	}
+};
+