Event/Threading Model

From reSIProcate
Jump to navigation Jump to search

The threading model in the stack requires the application to build an FdSet and call process on the stack. The select call needs a timeout value which the stack can also determine. The application may need to add its own file descriptors and timers as well.

buildFdSet[edit]

  • anything in the stack or the application that uses a file descriptor needs to add itself to the FdSet
  • this should start with an empty FdSet
  • next call SipStack::buildFdSet and this will add the file descriptors for all of the transports, connections and the dns provider
  • next add any application file descriptors

getTimeTillNextProcess[edit]

  • determines the minimum time till any timer in the application or stack will fire
  • if anything in the stack needs to process immediately, short circuit and return 0. (Currently, the dns provider short circuits with a value of 50ms?)

select[edit]

  • call select either in the Application or in a StackThread and pass in the two things constructed above

process[edit]

  • after select returns, pass the now marked up FdSet to SipStack::process
  • process delegates to anything in the SipStack that needs cycles periodically
    • ask the StatisticsManager to generate its stats
    • ask the Transports to send/receive and accept new connections
    • give the dns provider / cache cycles
    • process App and Transaction Timers
    • handle all outstanding events affecting TransactionState
    • handle TU shutdown related events


WARNING!!! Under windows the default FD_SETSIZE is 64 so using TCP/TLS transports is limited