src/ipc/Coordinator.h

   1 /*
   2  * $Id$
   3  *
   4  * DEBUG: section 54    Interprocess Communication
   5  *
   6  */
   7
   8 #ifndef SQUID_IPC_COORDINATOR_H
   9 #define SQUID_IPC_COORDINATOR_H
  10
  11 #include "Array.h"
  12 #include "ipc/Messages.h"
  13 #include "ipc/Port.h"
  14 #include "ipc/SharedListen.h"
  15 #include "ipc/StrandCoords.h"
  16 #include "ipc/StrandSearch.h"
  17 #include "mgr/forward.h"
  18 #if SQUID_SNMP
  19 #include "snmp/forward.h"
  20 #endif
  21 #include <list>
  22 #include <map>
  23
  24 namespace Ipc
  25 {
  26
  27 ///  Coordinates shared activities of Strands (Squid processes or threads)
  28 class Coordinator: public Port
  29 {
  30 public:
  31     static Coordinator* Instance();
  32
  33 public:
  34     Coordinator();
  35
  36     void broadcastSignal(int sig) const; ///< send sig to registered strands
  37
  38     const StrandCoords &strands() const; ///< currently registered strands
  39
  40 protected:
  41     virtual void start(); // Port (AsyncJob) API
  42     virtual void receive(const TypedMsgHdr& message); // Port API
  43
  44     StrandCoord* findStrand(int kidId); ///< registered strand or NULL
  45     void registerStrand(const StrandCoord &); ///< adds or updates existing
  46     void handleRegistrationRequest(const HereIamMessage &); ///< register,ACK
  47
  48     /// answer the waiting search request
  49     void notifySearcher(const StrandSearchRequest &request, const StrandCoord&);
  50     /// answers or queues the request if the answer is not yet known
  51     void handleSearchRequest(const StrandSearchRequest &request);
  52
  53     /// returns cached socket or calls openListenSocket()
  54     void handleSharedListenRequest(const SharedListenRequest& request);
  55     void handleCacheMgrRequest(const Mgr::Request& request);
  56     void handleCacheMgrResponse(const Mgr::Response& response);
  57 #if SQUID_SNMP
  58     void handleSnmpRequest(const Snmp::Request& request);
  59     void handleSnmpResponse(const Snmp::Response& response);
  60 #endif
  61     /// calls comm_open_listener()
  62     Comm::ConnectionPointer openListenSocket(const SharedListenRequest& request, int &errNo);
  63
  64 private:
  65     StrandCoords strands_; ///< registered processes and threads
  66
  67     typedef std::list<StrandSearchRequest> Searchers; ///< search requests
  68     Searchers searchers; ///< yet unanswered search requests in arrival order
  69
  70     typedef std::map<OpenListenerParams, Comm::ConnectionPointer> Listeners; ///< params:connection map
  71     Listeners listeners; ///< cached comm_open_listener() results
  72
  73     static Coordinator* TheInstance; ///< the only class instance in existence
  74
  75 private:
  76     Coordinator(const Coordinator&); // not implemented
  77     Coordinator& operator =(const Coordinator&); // not implemented
  78
  79     CBDATA_CLASS2(Coordinator);
  80 };
  81
  82 } // namespace Ipc
  83
  84 #endif /* SQUID_IPC_COORDINATOR_H */