Method parse

dependencies/httplib/httplib.h:3776–3901

  bool is_valid() const { return is_valid_; }

  bool parse(const char *buf, size_t n, const ContentReceiver &content_callback,
             const MultipartContentHeader &header_callback) {

    // TODO: support 'filename*'
    static const std::regex re_content_disposition(
        R"~(^Content-Disposition:\s*form-data;\s*name="(.*?)"(?:;\s*filename="(.*?)")?(?:;\s*filename\*=\S+)?\s*$)~",
        std::regex_constants::icase);

    static const std::string dash_ = "--";
    static const std::string crlf_ = "\r\n";

    buf_append(buf, n);

    while (buf_size() > 0) {
      switch (state_) {
      case 0: { // Initial boundary
        auto pattern = dash_ + boundary_ + crlf_;
        if (pattern.size() > buf_size()) { return true; }
        if (!buf_start_with(pattern)) { return false; }
        buf_erase(pattern.size());
        state_ = 1;
        break;
      }
      case 1: { // New entry
        clear_file_info();
        state_ = 2;
        break;
      }
      case 2: { // Headers
        auto pos = buf_find(crlf_);
        if (pos > CPPHTTPLIB_HEADER_MAX_LENGTH) { return false; }
        while (pos < buf_size()) {
          // Empty line
          if (pos == 0) {
            if (!header_callback(file_)) {
              is_valid_ = false;
              return false;
            }
            buf_erase(crlf_.size());
            state_ = 3;
            break;
          }

          static const std::string header_name = "content-type:";
          const auto header = buf_head(pos);
          if (start_with_case_ignore(header, header_name)) {
            file_.content_type = trim_copy(header.substr(header_name.size()));
          } else {
            std::smatch m;
            if (std::regex_match(header, m, re_content_disposition)) {
              file_.name = m[1];
              file_.filename = m[2];
            }
          }

          buf_erase(pos + crlf_.size());
          pos = buf_find(crlf_);
        }