fix 100 response with headers

[catbro666]

The 100 reponse is not processed correctly. After receiving the 100 status line, it only reads a line here and assumes there’s no headers. Then it directly tries to receive the status line of the next response here. If there are headers after 100 statue line, it will fail there.

I checked the RFC (section 5.2.1 and 6.2.1). Unfortunately, the specification does not explicitly require or prohibit the inclusion of headers in the 100 response. I tested many sites (httpbin.org, mockbin.org, hurl.it, webhook.site, codepunker.com, typicode.com), all of them don’t include any headers. But the squid proxy includes a header of Connection: keep-alive. So it’s better to be compatible with both cases.

[pintsized]

Amazing, thank you for this! This issue was first reported eight years ago :) #32

PR looks good to me at first glance, just an unused variable which is failing the luacheck test. Please fix this, and I'll do a proper review later today.

[catbro666]

@pintsized Could you help bump the version?

[pintsized]

v0.17.1 just released, to both luarocks and opm.