root/examples/mqueue-cpp/mqueue.h

INCLUDED FROM

   1 // -*- mode: C++ -*-
   2 //
   3 // mqueue.h - a simple-mineded message queue with priority
   4 //
   5 //   The mqueue-cpp extension module to show how to embed external C++
   6 //   library in Gauche.
   7 //   This file is a header of a supposed external C++ library, knowing
   8 //   nothing about Gauche.  In typical case, such external library is
   9 //   provided by the third party.
  10 //
  12 #ifndef MQUEUE_H
  13 #define MQUEUE_H
  15 #include <queue>
  16 #include <string>
  17 #include <set>
using namespace std;
class Message {
public:
Message(string body_, int urgency_ = 0)
  24         : body(body_), urgency(urgency_)
  25         {}
bool operator< (const Message& m) const {
  28         return urgency < m.urgency;
  29     }
  31     int getUrgency() const { return urgency;}
string getBody() const { return body; }
private:
string body;
  36     int urgency;
  37 };
class MQueueException {
public:
string reason;
MQueueException(string reason_) : reason(reason_) {}
  43 };
class MQueue {
public:
MQueue(string name_) : name(name_) { registerSelf(); }
  48     ~MQueue() { unregisterSelf(); }
string getName() const { return name; }
  52     // Basic queue operations.  The client doesn't need to know
  53     // about Message.
bool empty() const      { return q.empty(); }
string popMessage() throw (MQueueException);
size_t pushMessage(string body, int urgency = 0);
  58     // One can find a previously created MQueue by its name.
  59     static MQueue *findByName(string name);
bool operator< (const MQueue& m) const { return name < m.name; }
private:
string name;
priority_queue<Message> q;
  67     static set<MQueue*> knownQueues;
  68     void registerSelf();
  69     void unregisterSelf();
  70 };
  73 #endif  // MQUEUE_H