/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */

/*

 *

 *  (C) 2001 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpiimpl.h"

/* -- Begin Profiling Symbol Block for routine MPI_Comm_join */

#if defined(HAVE_PRAGMA_WEAK)

#pragma weak MPI_Comm_join = PMPI_Comm_join

#elif defined(HAVE_PRAGMA_HP_SEC_DEF)

#pragma _HP_SECONDARY_DEF PMPI_Comm_join  MPI_Comm_join

#elif defined(HAVE_PRAGMA_CRI_DUP)

#pragma _CRI duplicate MPI_Comm_join as PMPI_Comm_join

#elif defined(HAVE_WEAK_ATTRIBUTE)

int MPI_Comm_join(int fd, MPI_Comm * intercomm) __attribute__ ((weak, alias("PMPI_Comm_join")));

#endif

/* -- End Profiling Symbol Block */

/* Prototypes for local functions */

PMPI_LOCAL int MPIR_fd_send(int, void *, int);

PMPI_LOCAL int MPIR_fd_recv(int, void *, int);

/* Define MPICH_MPI_FROM_PMPI if weak symbols are not supported to build

   the MPI routines */

#ifndef MPICH_MPI_FROM_PMPI

#undef MPI_Comm_join

#define MPI_Comm_join PMPI_Comm_join

#ifdef HAVE_ERRNO_H

#include <errno.h>      /* needed for read/write error codes */

#endif

#ifdef HAVE_WINDOWS_H

#define SOCKET_EINTR        WSAEINTR

#else

#ifdef HAVE_SYS_SOCKET_H

#include <sys/socket.h>

#endif

#define SOCKET_EINTR        EINTR

#endif

PMPI_LOCAL int MPIR_fd_send(int fd, void *buffer, int length)

{

    int result, num_bytes;

    while (length) {

        /* The expectation is that the length of a join message will fit

         * in an int.  For Unixes that define send as returning ssize_t,

         * we can safely cast this to an int. */

        num_bytes = (int) send(fd, buffer, length, 0);

        /* --BEGIN ERROR HANDLING-- */

        if (num_bytes == -1) {

#ifdef HAVE_WINDOWS_H

            result = WSAGetLastError();

#else

            result = errno;

#endif

            if (result == SOCKET_EINTR)

                continue;

            else

                return result;

        }

        /* --END ERROR HANDLING-- */

        else {

            length -= num_bytes;

            buffer = (char *) buffer + num_bytes;

        }

    }

    return 0;

}

PMPI_LOCAL int MPIR_fd_recv(int fd, void *buffer, int length)

{

    int result, num_bytes;

    while (length) {

        /* See discussion on send above for the cast to int. */

        num_bytes = (int) recv(fd, buffer, length, 0);

        /* --BEGIN ERROR HANDLING-- */

        if (num_bytes == -1) {

#ifdef HAVE_WINDOWS_H

            result = WSAGetLastError();

#else

            result = errno;

#endif

            if (result == SOCKET_EINTR)

                continue;

            else

                return result;

        }

        /* --END ERROR HANDLING-- */

        else {

            length -= num_bytes;

            buffer = (char *) buffer + num_bytes;

        }

    }

    return 0;

}

#endif

#undef FUNCNAME

#define FUNCNAME MPI_Comm_join

#undef FCNAME

#define FCNAME MPL_QUOTE(FUNCNAME)

/*@

   MPI_Comm_join - Create a communicator by joining two processes connected by

     a socket.

Input Parameters:

. fd - socket file descriptor

Output Parameters:

. intercomm - new intercommunicator (handle)

 Notes:

  The socket must be quiescent before 'MPI_COMM_JOIN' is called and after

  'MPI_COMM_JOIN' returns. More specifically, on entry to 'MPI_COMM_JOIN', a

  read on the socket will not read any data that was written to the socket

  before the remote process called 'MPI_COMM_JOIN'.

.N ThreadSafe

.N Fortran

.N Errors

.N MPI_SUCCESS

.N MPI_ERR_ARG

@*/

int MPI_Comm_join(int fd, MPI_Comm * intercomm)

{

    int mpi_errno = MPI_SUCCESS, err;

    MPIR_Comm *intercomm_ptr;

    char *local_port, *remote_port;

    MPIR_CHKLMEM_DECL(2);

    MPIR_FUNC_TERSE_STATE_DECL(MPID_STATE_MPI_COMM_JOIN);

    MPIR_ERRTEST_INITIALIZED_ORDIE();

    MPID_THREAD_CS_ENTER(GLOBAL, MPIR_THREAD_GLOBAL_ALLFUNC_MUTEX);

    MPIR_FUNC_TERSE_ENTER(MPID_STATE_MPI_COMM_JOIN);

    /* ... body of routine ...  */

    MPIR_CHKLMEM_MALLOC(local_port, char *, MPI_MAX_PORT_NAME, mpi_errno, "local port name",

                        MPL_MEM_DYNAMIC);

    MPIR_CHKLMEM_MALLOC(remote_port, char *, MPI_MAX_PORT_NAME, mpi_errno, "remote port name",

                        MPL_MEM_DYNAMIC);

    MPL_VG_MEM_INIT(local_port, MPI_MAX_PORT_NAME * sizeof(char));

    mpi_errno = MPIR_Open_port_impl(NULL, local_port);

    MPIR_ERR_CHKANDJUMP((mpi_errno != MPI_SUCCESS), mpi_errno, MPI_ERR_OTHER, "**openportfailed");

    err = MPIR_fd_send(fd, local_port, MPI_MAX_PORT_NAME);

    MPIR_ERR_CHKANDJUMP1((err != 0), mpi_errno, MPI_ERR_INTERN, "**join_send", "**join_send %d",

                         err);

    err = MPIR_fd_recv(fd, remote_port, MPI_MAX_PORT_NAME);

    MPIR_ERR_CHKANDJUMP1((err != 0), mpi_errno, MPI_ERR_INTERN, "**join_recv", "**join_recv %d",

                         err);

    MPIR_ERR_CHKANDJUMP2((strcmp(local_port, remote_port) == 0), mpi_errno, MPI_ERR_INTERN,

                         "**join_portname", "**join_portname %s %s", local_port, remote_port);

    if (strcmp(local_port, remote_port) < 0) {

        MPIR_Comm *comm_self_ptr;

        MPIR_Comm_get_ptr(MPI_COMM_SELF, comm_self_ptr);

        mpi_errno = MPIR_Comm_accept_impl(local_port, NULL, 0, comm_self_ptr, &intercomm_ptr);

        if (mpi_errno)

            MPIR_ERR_POP(mpi_errno);

    } else {

        MPIR_Comm *comm_self_ptr;

        MPIR_Comm_get_ptr(MPI_COMM_SELF, comm_self_ptr);

        mpi_errno = MPIR_Comm_connect_impl(remote_port, NULL, 0, comm_self_ptr, &intercomm_ptr);

        if (mpi_errno)

            MPIR_ERR_POP(mpi_errno);

    }

    mpi_errno = MPIR_Close_port_impl(local_port);

    if (mpi_errno)

        MPIR_ERR_POP(mpi_errno);

    MPIR_OBJ_PUBLISH_HANDLE(*intercomm, intercomm_ptr->handle);

    /* ... end of body of routine ... */

  fn_exit:

    MPIR_CHKLMEM_FREEALL();

    MPIR_FUNC_TERSE_EXIT(MPID_STATE_MPI_COMM_JOIN);

    MPID_THREAD_CS_EXIT(GLOBAL, MPIR_THREAD_GLOBAL_ALLFUNC_MUTEX);

    return mpi_errno;

  fn_fail:

    /* --BEGIN ERROR HANDLING-- */

#ifdef HAVE_ERROR_CHECKING

    {

        mpi_errno =

            MPIR_Err_create_code(mpi_errno, MPIR_ERR_RECOVERABLE, FCNAME, __LINE__, MPI_ERR_OTHER,

                                 "**mpi_comm_join", "**mpi_comm_join %d %p", fd, intercomm);

    }

#endif

    mpi_errno = MPIR_Err_return_comm(NULL, FCNAME, mpi_errno);

    goto fn_exit;

    /* --END ERROR HANDLING-- */

}