Fix: Query parameter including query delimiter ('?') not being parsed properly

[davidalo]

When query delimiter ? is contained inside the query parameters, split function is cutting it and query parameters and not being parsed properly.

As an example:

/regex-with-delimiter?key=^(?.*(value))

This PR fixes it by adding m (maximum) parameter to details::split. This parameter indicates the maximum number of parts which will be got when splitting: -1 (infinite, no max), >= 0.

In Server::parse_request_line we use it as m=2 so we only get two parts: url and query parameters. By this way, we avoid splitting query parameters if they contain ?.

[yhirose]

@davidalo thank you very for your pull request. The change looks good to me. Could you make a couple of minor adjustments to make the code more readable?

1. Change int for m to size_t
2. Change -1 to std::numeric_limits<size_t>::max()
3. Make the following helper function to pass std::numeric_limits<size_t>::max()

inline void split(const char *b, const char *e, char d,
                  std::function<void(const char *, const char *)> fn) {
  split(b, e, d, std::numeric_limits<size_t>::max(), fn);
}

4. Change all the callers back to originals
5. Change the line if (b[i] == d && (m < 0 || count < m)) { to if (b[i] == d && count < m) {

[davidalo]

Sure, I will make those changes and notify you when available. Thanks for your reply.

[davidalo]

@yhirose I made those adjustments and I fixed conflicts. PR should be ready now.

[yhirose]

@davidalo thanks a lot for the fine contribution!