/*
 * -----------------------------------------------------------------
 * $Revision: 4490 $
 * $Date: 2015-04-30 16:55:37 -0700 (Thu, 30 Apr 2015) $
 * ----------------------------------------------------------------- 
 * Programmer(s): Aaron Collier and Radu Serban @ LLNL
 * -----------------------------------------------------------------
 * LLNS Copyright Start
 * Copyright (c) 2014, Lawrence Livermore National Security
 * This work was performed under the auspices of the U.S. Department 
 * of Energy by Lawrence Livermore National Laboratory in part under 
 * Contract W-7405-Eng-48 and in part under Contract DE-AC52-07NA27344.
 * Produced at the Lawrence Livermore National Laboratory.
 * All rights reserved.
 * For details, see the LICENSE file.
 * LLNS Copyright End
 * -----------------------------------------------------------------
 * This is the header file for the CVODES scaled preconditioned 
 * Bi-CGSTAB linear solver, CVSPBCG.
 *
 * Part I contains function prototypes for using CVSPBCG on forward 
 * problems (IVP integration and/or FSA)
 *
 * Part II contains function prototypes for using CVSPBCG on adjoint 
 * (backward) problems
 * -----------------------------------------------------------------
 */

#ifndef _CVSSPBCG_H
#define _CVSSPBCG_H

#include <cvodes/cvodes_spils.h>
#include <sundials/sundials_spbcgs.h>

#ifdef __cplusplus  /* wrapper to enable C++ usage */
extern "C" {
#endif

/* 
 * -----------------------------------------------------------------
 * PART I - forward problems
 * -----------------------------------------------------------------
 */

/*
 * -----------------------------------------------------------------
 * Function : CVSpbcg
 * -----------------------------------------------------------------
 * A call to the CVSpbcg function links the main CVODE integrator
 * with the CVSPBCG linear solver.
 *
 * cvode_mem is the pointer to the integrator memory returned by
 *           CVodeCreate.
 *
 * pretype   is the type of user preconditioning to be done.
 *           This must be one of the four enumeration constants
 *           PREC_NONE, PREC_LEFT, PREC_RIGHT, or PREC_BOTH defined
 *           in iterative.h. These correspond to no preconditioning,
 *           left preconditioning only, right preconditioning
 *           only, and both left and right preconditioning,
 *           respectively.
 *
 * maxl      is the maximum Krylov dimension. This is an
 *           optional input to the CVSPBCG solver. Pass 0 to
 *           use the default value CVSPILS_MAXL=5.
 *
 * The return value of CVSpbcg is one of:
 *    CVSPILS_SUCCESS   if successful
 *    CVSPILS_MEM_NULL  if the cvode memory was NULL
 *    CVSPILS_MEM_FAIL  if there was a memory allocation failure
 *    CVSPILS_ILL_INPUT if a required vector operation is missing
 * The above constants are defined in cvodes_spils.h
 * -----------------------------------------------------------------
 */

SUNDIALS_EXPORT int CVSpbcg(void *cvode_mem, int pretype, int maxl);

/* 
 * -----------------------------------------------------------------
 * PART II - backward problems
 * -----------------------------------------------------------------
 */

/*
 * -----------------------------------------------------------------
 * Function: CVSpbcgB
 * -----------------------------------------------------------------
 * CVSpbcgB links the main CVODES integrator with the CVSpbcg
 * linear solver for the backward integration.
 * The 'which' argument is the int returned by CVodeCreateB.
 * -----------------------------------------------------------------
 */

SUNDIALS_EXPORT int CVSpbcgB(void *cvode_mem, int which,
                             int pretypeB, int maxlB);


#ifdef __cplusplus
}
#endif

#endif
