CURLM_STATE_WAITRESOLVE
Curl_resolver_getaddrinfo
End
Curl_client_write
CURLM_STATE_WAITPERFORM
CURLM_STATE_DO_DONE
是
CURLM_STATE_WAITCONNECT
Curl_recv_plain
CURLM_STATE_DO
Curl_http_connect
Curl_client_chop_write
CURLM_STATE_PERFORM
解析完成
CURLM_STATE_CONNECT
Curl_http
CURLM_STATE_INIT
Curl_send_plain
否
Curl_http_setup_conn
CURLM_STATE_SENDPROTOCONNECT
是否需要域名解析？
用户回调
