/* -*- Mode: C; c-basic-offset:4 ; -*- */
/*
 *
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

#include "mpiimpl.h"

/* -- Begin Profiling Symbol Block for routine MPI_Irecv */
#if defined(HAVE_PRAGMA_WEAK)
#pragma weak MPI_Irecv = PMPI_Irecv
#elif defined(HAVE_PRAGMA_HP_SEC_DEF)
#pragma _HP_SECONDARY_DEF PMPI_Irecv  MPI_Irecv
#elif defined(HAVE_PRAGMA_CRI_DUP)
#pragma _CRI duplicate MPI_Irecv as PMPI_Irecv
#endif
/* -- End Profiling Symbol Block */

/* Define MPICH_MPI_FROM_PMPI if weak symbols are not supported to build
   the MPI routines */
#ifndef MPICH_MPI_FROM_PMPI
#undef MPI_Irecv
#define MPI_Irecv PMPI_Irecv

#endif

#undef FUNCNAME
#define FUNCNAME MPI_Irecv

/*@
    MPI_Irecv - Begins a nonblocking receive

Input Parameters:
+ buf - initial address of receive buffer (choice) 
. count - number of elements in receive buffer (integer) 
. datatype - datatype of each receive buffer element (handle) 
. source - rank of source (integer) 
. tag - message tag (integer) 
- comm - communicator (handle) 

Output Parameter:
. request - communication request (handle) 

.N ThreadSafe

.N Fortran

.N Errors
.N MPI_SUCCESS
.N MPI_ERR_COMM
.N MPI_ERR_COUNT
.N MPI_ERR_TYPE
.N MPI_ERR_TAG
.N MPI_ERR_RANK
.N MPI_ERR_EXHAUSTED
@*/
int MPI_Irecv(void *buf, int count, MPI_Datatype datatype, int source,
	      int tag, MPI_Comm comm, MPI_Request *request)
{
    static const char FCNAME[] = "MPI_Irecv";
    int mpi_errno = MPI_SUCCESS;
    MPID_Comm *comm_ptr = NULL;
    MPID_Request *request_ptr = NULL;
    MPID_MPI_STATE_DECL(MPID_STATE_MPI_IRECV);

    MPIR_ERRTEST_INITIALIZED_ORDIE();
    
    MPIU_THREAD_CS_ENTER(ALLFUNC,);
    MPID_MPI_PT2PT_FUNC_ENTER_BACK(MPID_STATE_MPI_IRECV);

    /* Validate handle parameters needing to be converted */
#   ifdef HAVE_ERROR_CHECKING
    {
        MPID_BEGIN_ERROR_CHECKS;
        {
	    MPIR_ERRTEST_COMM(comm, mpi_errno);
            if (mpi_errno) goto fn_fail;
	}
        MPID_END_ERROR_CHECKS;
    }
#   endif /* HAVE_ERROR_CHECKING */
    
    /* Convert MPI object handles to object pointers */
    MPID_Comm_get_ptr( comm, comm_ptr );

    /* Validate parameters if error checking is enabled */
#   ifdef HAVE_ERROR_CHECKING
    {
        MPID_BEGIN_ERROR_CHECKS;
        {
            MPID_Comm_valid_ptr( comm_ptr, mpi_errno );
            if (mpi_errno) goto fn_fail;
	    
	    MPIR_ERRTEST_COUNT(count, mpi_errno);
	    MPIR_ERRTEST_RECV_RANK(comm_ptr, source, mpi_errno);
	    MPIR_ERRTEST_RECV_TAG(tag, mpi_errno);
	    MPIR_ERRTEST_ARGNULL(request,"request",mpi_errno);
	    if (mpi_errno) goto fn_fail;

	    /* Validate datatype handle */
	    MPIR_ERRTEST_DATATYPE(datatype, "datatype", mpi_errno);
	    
	    /* Validate datatype object */
	    if (HANDLE_GET_KIND(datatype) != HANDLE_KIND_BUILTIN)
	    {
		MPID_Datatype *datatype_ptr = NULL;

		MPID_Datatype_get_ptr(datatype, datatype_ptr);
		MPID_Datatype_valid_ptr(datatype_ptr, mpi_errno);
		MPID_Datatype_committed_ptr(datatype_ptr, mpi_errno);
		if (mpi_errno) goto fn_fail;
	    }
	    
	    /* Validate buffer */
	    MPIR_ERRTEST_USERBUFFER(buf,count,datatype,mpi_errno);
            if (mpi_errno) goto fn_fail;
        }
        MPID_END_ERROR_CHECKS;
    }
#   endif /* HAVE_ERROR_CHECKING */

    /* ... body of routine ...  */
    
    mpi_errno = MPID_Irecv(buf, count, datatype, source, tag, comm_ptr, 
			   MPID_CONTEXT_INTRA_PT2PT, &request_ptr);
    if (mpi_errno != MPI_SUCCESS) goto fn_fail;

    /* return the handle of the request to the user */
    /* MPIU_OBJ_HANDLE_PUBLISH is unnecessary for irecv, lower-level access is
     * responsible for its own consistency, while upper-level field access is
     * controlled by the completion counter */
    *request = request_ptr->handle;

    /* ... end of body of routine ... */
    
  fn_exit:
    MPID_MPI_PT2PT_FUNC_EXIT_BACK(MPID_STATE_MPI_IRECV);
    MPIU_THREAD_CS_EXIT(ALLFUNC,);
    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_irecv",
	    "**mpi_irecv %p %d %D %i %t %C %p", buf, count, datatype, source, tag, comm, request);
    }
#   endif
    mpi_errno = MPIR_Err_return_comm( comm_ptr, FCNAME, mpi_errno );
    goto fn_exit;
    /* --END ERROR HANDLING-- */
}
