| Value | Meaning |
|---|---|
| NONE0 | |
| _AUTHORITY1 | header field seen so far |
| _PATH1 << 1 | |
| _METHOD1 << 2 | |
| _SCHEME1 << 3 | |
| HOST1 << 4 | host is not pseudo header, but we require either host or :authority |
| _STATUS1 << 5 | |
| REQ_HEADERS_METHOD | _PATH | _SCHEME | required header fields for HTTP request except for CONNECT method. |
| PSEUDO_HEADER_DISALLOWED1 << 6 | |
| METH_CONNECT1 << 7 | |
| METH_HEAD1 << 8 | |
| METH_OPTIONS1 << 9 | |
| METH_ALLMETH_CONNECT | METH_HEAD | METH_OPTIONS | |
| PATH_REGULAR1 << 10 | |
| PATH_ASTERISK1 << 11 | |
| SCHEME_HTTP1 << 12 | |
| EXPECT_FINAL_RESPONSE1 << 13 |
HTTP related flags to enforce HTTP semantics