msg.h

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* to you under the Apache License, Version 2.0 (the
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#ifndef SINGA_COMMUNICATION_MSG_H_
#define SINGA_COMMUNICATION_MSG_H_

// TODO(wangwei): make it a compiler argument
#define USE_ZMQ

#include <utility>
#ifdef USE_ZMQ
#include <czmq.h>
#endif

namespace singa {
inline int Addr(int grp, int id_or_proc, int type) {
  return (grp << 16) | (id_or_proc << 8) | type;
}

inline int AddrGrp(int addr) {
  return addr >> 16;
}

inline int AddrID(int addr) {
  static const int mask = (1 << 8) - 1;
  return (addr >> 8) & mask;
}

inline int AddrProc(int addr) {
  return AddrID(addr);
}

inline int AddrType(int addr) {
  static const int mask = (1 << 8) -1;
  return addr & mask;
}

class Msg {
 public:
  ~Msg();
  Msg();
  Msg(int src, int dst);
  Msg(const Msg& msg);
  void SwapAddr();
  void AddFrame(const void* addr, int nBytes);
  int FrameSize();
  void* FrameData();
  char* FrameStr();
  void FirstFrame();
  void LastFrame();
  bool NextFrame();
  int AddFormatFrame(const char *format, ...);
  int ParseFormatFrame(const char* format, ...);

#ifdef USE_ZMQ
  void ParseFromZmsg(zmsg_t* msg);
  zmsg_t* DumpToZmsg();
#endif

  int size() const;
  inline void set_src(int addr) { src_ = addr; }
  inline int src() const { return src_; }
  inline void set_dst(int addr) { dst_ = addr; }
  inline int dst() const { return dst_; }
  inline void set_type(int type) { type_ = type; }
  inline int type() const { return type_; }
  inline void set_trgt(int val, int version) {
    trgt_val_ = val;
    trgt_version_ = version;
  }
  inline int trgt_val() const { return trgt_val_; }
  inline int trgt_version() const { return trgt_version_; }

 protected:
  int src_ = 0;
  int dst_ = 0;
  int type_ = 0;
  int trgt_val_ = 0;
  int trgt_version_ = 0;
#ifdef USE_ZMQ
  zmsg_t* msg_ = nullptr;
  zframe_t *frame_ = nullptr;
#endif
};

inline void DeleteMsg(Msg** msg) {
  delete *msg;
  *msg = nullptr;
}

}  // namespace singa

#endif  // SINGA_COMMUNICATION_MSG_H_