Hm, didn't nginx do something similarly "ugly" for a while? Like inspecting the (completely making it up here) second character to see if it's 'E'?
A quick look now suggests they are using a parser generator now.
A quick look now suggests they are using a parser generator now.
When the length of verb is 4, it checks if the second character is 'O' before trying the full string comparisons, probably because there are 4 possibilities with it (POST, COPY, MOVE, LOCK) vs only one without (HEAD).
It starts at line 180.
That being said, in nginx case, it's a preliminary check, just to avoid doing some full string comparisons in a very specific case. On the other hand, the nodejs directly does a 'parser->method = HTTP_CONNECT' after checking one character. It seems like it actually checks the other characters afterwards in some cases, but this affectation is quite misleading.
[0] http://hg.nginx.org/nginx/file/abf7813b927e/src/http/ngx_htt...
Actually, if you look at the nginx source I linked, the comparisons of the full strings are hidden behind macros because they do the opposite: they group characters 4 by 4, and do 32bit int comparisons as much as possible.