Method FileDumper

src/bvar/variable.cpp:569–583

class FileDumper : public Dumper {
public:
    FileDumper(const std::string& filename, butil::StringPiece s/*prefix*/)
        : _filename(filename), _fp(NULL) {
        // setting prefix.
        // remove trailing spaces.
        const char* p = s.data() + s.size();
        for (; p != s.data() && isspace(p[-1]); --p) {}
        s.remove_suffix(s.data() + s.size() - p);
        // normalize it.
        if (!s.empty()) {
            to_underscored_name(&_prefix, s);
            if (butil::back_char(_prefix) != '_') {
                _prefix.push_back('_');
            }
        }
    }

    ~FileDumper() {
        close();