mariadb-columnstore-engine/utils/messageqcpp/inetstreamsocket.h

/* Copyright (C) 2014 InfiniDB, Inc.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; version 2 of
   the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

/***********************************************************************
*   $Id: inetstreamsocket.h 3632 2013-03-13 18:08:46Z pleblanc $
*
*
***********************************************************************/
/** @file */
#ifndef MESSAGEQCPP_INETSTREAMSOCKET_H
#define MESSAGEQCPP_INETSTREAMSOCKET_H

#include <ctime>
#include <unistd.h>
#ifndef _MSC_VER
#include <netinet/in.h>
#endif
#include <cstring>

#include "socket.h"
#include "socketparms.h"
#include "bytestream.h"

#if defined(_MSC_VER) && defined(xxxINETSTREAMSOCKET_DLLEXPORT)
#define EXPORT __declspec(dllexport)
#else
#define EXPORT
#endif

class MessageQTestSuite;

namespace messageqcpp
{
class IOSocket;

/// random # marking the beginning of a ByteStream in the stream
const uint32_t BYTESTREAM_MAGIC = 0x14fbc137;
const uint32_t COMPRESSED_BYTESTREAM_MAGIC = 0x14fbc138;

/** An Inet Stream Socket
 *
 */
class InetStreamSocket : public Socket
{
public:
    /** ctor
     *
     */
    explicit InetStreamSocket(size_t blocksize = ByteStream::BlockSize);

    /** dtor
     *
     */
    virtual ~InetStreamSocket();

    /** copy ctor
     *
     */
    InetStreamSocket(const InetStreamSocket& rhs);

    /** assign op
     *
     */
    virtual InetStreamSocket& operator=(const InetStreamSocket& rhs);

    /** fSocket mutator
     *
     */
    inline virtual void socketParms(const SocketParms& socket);

    /** fSocket accessor
     *
     */
    inline virtual const SocketParms socketParms() const;

    /** sockaddr mutator
     *
     */
    inline virtual void sa(const sockaddr* sa);

    /** call socket() to get a sd
     *
     */
    virtual void open();

    /** close the sd
     *
     */
    virtual void close();

    /** test if this socket is open
     *
     */
    inline virtual const bool isOpen() const;

    /** read a message from the socket
     *
     * wait for and return a message from the socket. The deafult timeout waits forever. Note that
     * eventhough struct timespec has nanosecond resolution, this method only has milisecond resolution.
     * @warning If you specify a timeout, the stream can be corrupted in certain
     * extreme circumstances.  The circumstance: receiving a portion of the message
     * followed by a timeout.  If the rest of the message is ever received, it
     * will be misinterpreted by the following read().  Symptom:  The caller will
     * receive an incomplete ByteStream
     * (do try-catch around all ">>" operations to detect underflow).  Mitigation:
     * the caller should not perform another read().  Caller should close the connection.
     * The behavior will be unpredictable and possibly fatal.
     * @note A fix is being reviewed but this is low-priority.
     */
    virtual const SBS read(const struct timespec* timeout = 0, bool* isTimeOut = NULL, Stats* stats = NULL) const;

    /** write a message to the socket
     *
     * write a message to the socket
     */
    virtual void write(const ByteStream& msg, Stats* stats = NULL);
    virtual void write_raw(const ByteStream& msg, Stats* stats = NULL) const;

    /** this version of write takes ownership of the bytestream
     */
    virtual void write(SBS msg, Stats* stats = NULL);

    /** bind to a port
     *
     */
    virtual void bind(const sockaddr* serv_addr);

    /** listen for connections
     *
     */
    virtual void listen(int backlog = 5);

    /** return an (accepted) IOSocket ready for I/O
     *
     */
    virtual const IOSocket accept(const struct timespec* timeout = 0);

    /** connect to a server socket
     *
     */
    virtual void connect(const sockaddr* serv_addr);

    /** dynamically allocate a copy of this object
     *
     */
    virtual Socket* clone() const;

    /** get a string rep of the object
     *
     */
    virtual const std::string toString() const;

    /** set the connection timeout (in ms)
     *
     */
    virtual void connectionTimeout(const struct ::timespec* timeout)
    {
        if (timeout) fConnectionTimeout = *timeout;
    }

    /** set the connection protocol to be synchronous
     *
     */
    virtual void syncProto(bool use)
    {
        fSyncProto = use;
    }

    const int getConnectionNum() const
    {
        return fSocketParms.sd();
    }

    /* The caller needs to know when/if the remote closes the connection or sends data.
     * Returns 0 on timeout, 1 if there is data to read, 2 if the connection was dropped.
     * On error 3 is returned.
     */
    static int pollConnection(int connectionNum, long msecs);

    /** return the address as a string
     *
     */
    virtual const std::string addr2String() const;

    /** compare 2 addresses
     *
     */
    virtual const bool isSameAddr(const Socket* rhs) const;

    /** ping an ip address
     *
     */
    EXPORT static int ping(const std::string& ipaddr, const struct timespec* timeout = 0);

    // Check if we are still connected
    virtual bool isConnected() const;

    // Check if the socket still has data pending

    virtual bool hasData() const;

    /*
     * allow test suite access to private data for OOB test
     */
    friend class ::MessageQTestSuite;

protected:
    static const int KERR_ERESTARTSYS = 512;

    void logIoError(const char* errMsg, int errNum) const;

    /** Empty the stream up to the beginning of the next ByteStream.
     *
     * Reads until the beginning of the next ByteStream is found.
     * @param msecs An optional timeout value.
     * @param residual Pass in an array of at least 8 bytes, on return it will contain
     * the first bytes of the stream.
     * @param reslen On return, it will contain the # of bytes in residual.
     * @return true if the next byte in the stream is the beginning of a ByteStream,
     * false otherwise.
     */
    virtual bool readToMagic(long msecs, bool* isTimeOut, Stats* stats) const;

    void do_write(const ByteStream& msg, uint32_t magic, Stats* stats = NULL) const;
    ssize_t written(int fd, const uint8_t* ptr, size_t nbytes) const;

    SocketParms fSocketParms;	/// The socket parms
    size_t fBlocksize;
    sockaddr_in fSa;

    // how long to wait for a connect() call to complete (in ms)
    struct ::timespec fConnectionTimeout;

    // use sync proto
    bool fSyncProto;

    /// The buffer used to scan for the ByteStream magic in the stream.
    mutable uint32_t fMagicBuffer;

private:
    void doCopy(const InetStreamSocket& rhs);
};

inline const bool InetStreamSocket::isOpen() const
{
    return (fSocketParms.sd() >= 0);
}
inline const SocketParms InetStreamSocket::socketParms() const
{
    return fSocketParms;
}
inline void InetStreamSocket::socketParms(const SocketParms& socketParms)
{
    fSocketParms = socketParms;
}
inline void InetStreamSocket::sa(const sockaddr* sa)
{
    memcpy(&fSa, sa, sizeof(sockaddr_in));
}

/**
 * stream an InetStreamSocket rep to any ostream
 */
inline std::ostream& operator<<(std::ostream& os, const InetStreamSocket& rhs)
{
    os << rhs.toString();
    return os;
}

} //namespace messageqcpp

#undef EXPORT

#endif //MESSAGEQCPP_INETSTREAMSOCKET_H