socket.cpp

Pegasus is an open-source implementationof the DMTF CIM and WBEM standards. It is designed to be por

//%2006////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2000, 2001, 2002 BMC Software; Hewlett-Packard Development
// Company, L.P.; IBM Corp.; The Open Group; Tivoli Systems.
// Copyright (c) 2003 BMC Software; Hewlett-Packard Development Company, L.P.;
// IBM Corp.; EMC Corporation, The Open Group.
// Copyright (c) 2004 BMC Software; Hewlett-Packard Development Company, L.P.;
// IBM Corp.; EMC Corporation; VERITAS Software Corporation; The Open Group.
// Copyright (c) 2005 Hewlett-Packard Development Company, L.P.; IBM Corp.;
// EMC Corporation; VERITAS Software Corporation; The Open Group.
// Copyright (c) 2006 Hewlett-Packard Development Company, L.P.; IBM Corp.;
// EMC Corporation; Symantec Corporation; The Open Group.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN
// ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED
// "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//==============================================================================
//
//%/////////////////////////////////////////////////////////////////////////////

#include "Socket.h"
#include "Network.h"
#include <cctype>
#include <cstring>
#include <Pegasus/Common/Sharable.h>
#include <Pegasus/Common/Logger.h>
#include <Pegasus/Common/System.h>

//------------------------------------------------------------------------------
//
// PEGASUS_RETRY_SYSTEM_CALL()
//
//     This macro repeats the given system call until it returns something
//     other than EINTR.
//
//------------------------------------------------------------------------------

#ifdef PEGASUS_OS_TYPE_WINDOWS
#   define PEGASUS_RETRY_SYSTEM_CALL(EXPR, RESULT) RESULT = EXPR
#else
#   define PEGASUS_RETRY_SYSTEM_CALL(EXPR, RESULT) \
        while (((RESULT = (EXPR)) == -1) && (errno == EINTR))
#endif

PEGASUS_NAMESPACE_BEGIN

static Uint32 _socketInterfaceRefCount = 0;

Sint32 Socket::read(SocketHandle socket, void* ptr, Uint32 size)
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    return ::recv(socket, (char*)ptr, size, 0);
#else
    int status;
    PEGASUS_RETRY_SYSTEM_CALL(::read(socket, (char*)ptr, size), status);
    return status;
#endif
}

Sint32 Socket::write(SocketHandle socket, const void* ptr, Uint32 size)
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    return ::send(socket, (const char*)ptr, size, 0);
#else
    int status;
    PEGASUS_RETRY_SYSTEM_CALL(::write(socket, (char*)ptr, size), status);
    return status;
#endif
}

Sint32 Socket::timedWrite(
    SocketHandle socket,
    const void* ptr,
    Uint32 size,
    Uint32 socketWriteTimeout)
{
    Sint32 bytesWritten = 0;
    Sint32 totalBytesWritten = 0;
    Boolean socketTimedOut = false;
    int selreturn = 0;
    while (1)
    {
#ifdef PEGASUS_OS_TYPE_WINDOWS
        PEGASUS_RETRY_SYSTEM_CALL(
            ::send(socket, (const char*)ptr, size, 0), bytesWritten);
#else
        PEGASUS_RETRY_SYSTEM_CALL(
            ::write(socket, (char*)ptr, size), bytesWritten);
#endif
        // Some data written this cycle ?
        // Add it to the total amount of written data.
        if (bytesWritten > 0)
        {
            totalBytesWritten += bytesWritten;
            socketTimedOut = false;
        }

        // All data written ? return amount of data written
        if ((Uint32)bytesWritten == size)
        {
            return totalBytesWritten;
        }
        // If data has been written partially, we resume writing data
        // this also accounts for the case of a signal interrupt
        // (i.e. errno = EINTR)
        if (bytesWritten > 0)
        {
            size -= bytesWritten;
            ptr = (void *)((char *)ptr + bytesWritten);
            continue;
        }
        // Something went wrong
        if (bytesWritten == PEGASUS_SOCKET_ERROR)
        {
            // if we already waited for the socket to get ready, bail out
            if (socketTimedOut) return bytesWritten;
#ifdef PEGASUS_OS_TYPE_WINDOWS
            if (WSAGetLastError() == WSAEWOULDBLOCK)
#else
            if (errno == EAGAIN || errno == EWOULDBLOCK)
#endif
            {
                fd_set fdwrite;
                 // max. timeout seconds waiting for the socket to get ready
                struct timeval tv = { socketWriteTimeout, 0 };
                FD_ZERO(&fdwrite);
                FD_SET(socket, &fdwrite);
                selreturn = select(FD_SETSIZE, NULL, &fdwrite, NULL, &tv);
                if (selreturn == 0) socketTimedOut = true; // ran out of time
                continue;
            }
            return bytesWritten;
        }
    }
}

void Socket::close(SocketHandle socket)
{
    if (socket != -1)
    {
#ifdef PEGASUS_OS_TYPE_WINDOWS
        if (!closesocket(socket))
            socket = -1;
#else
        int status;
        PEGASUS_RETRY_SYSTEM_CALL(::close(socket), status);

        if (status == 0)
            socket = -1;
#endif
    }
}

void Socket::enableBlocking(SocketHandle socket)
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    unsigned long flag = 0;
    ioctlsocket(socket, FIONBIO, &flag);
#else
    int flags = fcntl(socket, F_GETFL, 0);
    flags &= ~O_NONBLOCK;
    fcntl(socket, F_SETFL, flags);
#endif
}

void Socket::disableBlocking(SocketHandle socket)
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    unsigned long flag = 1;
    ioctlsocket(socket, FIONBIO, &flag);
#else
    int flags = fcntl(socket, F_GETFL, 0);
    flags |= O_NONBLOCK;
    fcntl(socket, F_SETFL, flags);
#endif
}

void Socket::initializeInterface()
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    if (_socketInterfaceRefCount == 0)
    {
        WSADATA tmp;

        if (WSAStartup(0x202, &tmp) == SOCKET_ERROR)
            WSACleanup();
    }

    _socketInterfaceRefCount++;
#endif
}

void Socket::uninitializeInterface()
{
#ifdef PEGASUS_OS_TYPE_WINDOWS
    _socketInterfaceRefCount--;

    if (_socketInterfaceRefCount == 0)
        WSACleanup();
#endif
}

//------------------------------------------------------------------------------
//
// _setTCPNoDelay()
//
//------------------------------------------------------------------------------

inline void _setTCPNoDelay(SocketHandle socket)
{
    // This function disables "Nagle's Algorithm" also known as "the TCP delay
    // algorithm", which causes read operations to obtain whatever data is
    // already in the input queue and then wait a little longer to see if
    // more data arrives. This algorithm optimizes the case in which data is
    // sent in only one direction but severely impairs performance of round
    // trip servers. Disabling TCP delay is a standard technique for round
    // trip servers.

   int opt = 1;
   setsockopt(socket, IPPROTO_TCP, TCP_NODELAY, (char*)&opt, sizeof(opt));
}
//------------------------------------------------------------------------------
//
// _setInformIfNewTCPIP()
//
//------------------------------------------------------------------------------
inline void _setInformIfNewTCPIP(SocketHandle socket)
{
#ifdef PEGASUS_OS_ZOS
   // This function enables the notification of the CIM Server that a new
   // TCPIP transport layer is active. This is needed to be aware of a
   // restart of the transport layer. When this option is in effect,
   // the accetp(), select(), and read() request will receive an errno=EIO.
   // Once this happens, the socket should be closed and create a new.

   int NewTcpipOn = 1;
   setibmsockopt(
       socket,
       SOL_SOCKET,
       SO_EioIfNewTP,
       (char*)&NewTcpipOn,
       sizeof(NewTcpipOn));
#endif
}


SocketHandle Socket::createSocket(int domain, int type, int protocol)
{
    SocketHandle newSocket;

    if (domain == AF_UNIX)
    {
        return socket(domain,type,protocol);
    }

    bool sendTcpipMsg = true;

    while (1)
    {
        newSocket = socket(domain,type,protocol);

        // The program should wait for transport layer to become ready.

        if (newSocket == PEGASUS_INVALID_SOCKET &&
           getSocketError() == PEGASUS_NETWORK_TCPIP_TRYAGAIN )
        {
           if (sendTcpipMsg)
           {
               Logger::put_l(
                   Logger::STANDARD_LOG, System::CIMSERVER, Logger::INFORMATION,
                   "Common.Socket.WAIT_FOR_TCPIP",
                   "TCP/IP temporary unavailable.");
               sendTcpipMsg=false;
           }

           System::sleep(30);
           continue;
        }
        else
        {
           break;
        }
    } // wait for the transport layer become ready.

    // Is the socket in an unrecoverable error ?
    if (newSocket == PEGASUS_INVALID_SOCKET)
    {
        // return immediate
        return PEGASUS_INVALID_SOCKET;
    }
    else
    {
        // set aditional socket options
        _setTCPNoDelay(newSocket);
        _setInformIfNewTCPIP(newSocket);

        return newSocket;
    }
}

PEGASUS_NAMESPACE_END