Function read_graph_header

cactus/graph/graph_io.cpp:366–382

    }

    GraphFile::GraphHeader read_graph_header(std::istream& in) {
        GraphFile::GraphHeader header;
        header.magic = read_u32(in);
        header.version = read_u32(in);
        header.node_count = read_u32(in);
        header.flags = read_u32(in);

        if (header.magic != CACTUS_GRAPH_MAGIC) {
            throw std::runtime_error("Invalid graph file: bad magic");
        }
        if (header.version != 1) {
            throw std::runtime_error("Unsupported graph file version: " +
                std::to_string(header.version));
        }

        return header;
    }

    GraphFile::NodeEntry read_node_entry(std::istream& in) {
        GraphFile::NodeEntry node;