called with Start() reporting errors on Starting the server

not thread safe

thread safe need to call TryCloseFd to really close it

get the next msg from recv queue, return nullptr if queue is empty the returned address is guaranteed to be 8 byte aligned if caller dont call Pop() l

called by CTL thread client is disconnected

called by CTL thread ptcp or shm files can't be open or are corrupt

called by APP thread

called by CTL thread server and client ptcp sequence number don't match, we need to fix it manually

called by APP thread

precondition: sockfd_ == fd_to_close_ == -1

the next seq_num peer side expect

called by CTL thread confirmation for client logon

called by tcp thread

called within Connect() Login rejected by server

called within Connect() confirmation for login success

called by CTL thread if accept the connection, set user_data in login_rsp and return grpid(start from 0) with respect to tcp or shm else set error_msg

submit the last msg from Alloc() and send out

safe if IsClosed

allocate a msg of specified size in send queue the returned address is guaranteed to be 8 byte aligned return nullptr if no enough space

check if seq_start <= ack_seq <= seq_end, considering uint32_t wrap around

Close this connection

connect and login to server, may block for a short time return true if success

safe if IsClosed

called within Connect() server and client ptcp sequence number don't match, we need to fix it manually

called within Connect() reporting errors on connecting to the server

poll control for handling new connections and keep shm connections alive

poll shm for serving shm connections

only for using shm

poll tcp for serving tcp connections

we need to PollTcp even if using shm

we have consumed the msg we got from Front()

consume the msg we got from Front() or polling function

for shm, same as Push for tcp, don't send out immediately as we have more to push

return false only if no pending data to send

start the server return true if success

stop the connection and close files