src/ipc/Coordinator.h

   1 /*
   2  * DEBUG: section 54    Interprocess Communication
   3  *
   4  */
   5
   6 #ifndef SQUID_IPC_COORDINATOR_H
   7 #define SQUID_IPC_COORDINATOR_H
   8
   9 #include "ipc/Messages.h"
  10 #include "ipc/Port.h"
  11 #include "ipc/SharedListen.h"
  12 #include "ipc/StrandCoords.h"
  13 #include "ipc/StrandSearch.h"
  14 #include "mgr/forward.h"
  15 #if SQUID_SNMP
  16 #include "snmp/forward.h"
  17 #endif
  18 #include <list>
  19 #include <map>
  20
  21 namespace Ipc
  22 {
  23
  24 ///  Coordinates shared activities of Strands (Squid processes or threads)
  25 class Coordinator: public Port
  26 {
  27 public:
  28     static Coordinator* Instance();
  29
  30 public:
  31     Coordinator();
  32
  33     void broadcastSignal(int sig) const; ///< send sig to registered strands
  34
  35     const StrandCoords &strands() const; ///< currently registered strands
  36
  37 protected:
  38     virtual void start(); // Port (AsyncJob) API
  39     virtual void receive(const TypedMsgHdr& message); // Port API
  40
  41     StrandCoord* findStrand(int kidId); ///< registered strand or NULL
  42     void registerStrand(const StrandCoord &); ///< adds or updates existing
  43     void handleRegistrationRequest(const HereIamMessage &); ///< register,ACK
  44
  45     /// answer the waiting search request
  46     void notifySearcher(const StrandSearchRequest &request, const StrandCoord&);
  47     /// answers or queues the request if the answer is not yet known
  48     void handleSearchRequest(const StrandSearchRequest &request);
  49
  50     /// returns cached socket or calls openListenSocket()
  51     void handleSharedListenRequest(const SharedListenRequest& request);
  52     void handleCacheMgrRequest(const Mgr::Request& request);
  53     void handleCacheMgrResponse(const Mgr::Response& response);
  54 #if SQUID_SNMP
  55     void handleSnmpRequest(const Snmp::Request& request);
  56     void handleSnmpResponse(const Snmp::Response& response);
  57 #endif
  58     /// calls comm_open_listener()
  59     Comm::ConnectionPointer openListenSocket(const SharedListenRequest& request, int &errNo);
  60
  61 private:
  62     StrandCoords strands_; ///< registered processes and threads
  63
  64     typedef std::list<StrandSearchRequest> Searchers; ///< search requests
  65     Searchers searchers; ///< yet unanswered search requests in arrival order
  66
  67     typedef std::map<OpenListenerParams, Comm::ConnectionPointer> Listeners; ///< params:connection map
  68     Listeners listeners; ///< cached comm_open_listener() results
  69
  70     static Coordinator* TheInstance; ///< the only class instance in existence
  71
  72 private:
  73     Coordinator(const Coordinator&); // not implemented
  74     Coordinator& operator =(const Coordinator&); // not implemented
  75
  76     CBDATA_CLASS2(Coordinator);
  77 };
  78
  79 } // namespace Ipc
  80
  81 #endif /* SQUID_IPC_COORDINATOR_H */