/* mpiutil.ac  -  Utility functions for MPI
   * Copyright (C) 1998, 1999 Free Software Foundation, Inc.
   *
   * This file is part of GnuPG.
   *
   * GnuPG 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; either version 2 of the License, or
   * (at your option) any later version.
   *
   * GnuPG 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
   */
  
  #include "mpi-internal.h"
  
  /****************
   * Note:  It was a bad idea to use the number of limbs to allocate
   *	  because on a alpha the limbs are large but we normally need
   *	  integers of n bits - So we should chnage this to bits (or bytes).
   *
   *	  But mpi_alloc is used in a lot of places :-)
   */
  MPI mpi_alloc(unsigned nlimbs)
  {
  	MPI a;
  
  	a = kmalloc(sizeof *a, GFP_KERNEL);
  	if (!a)
  		return a;
  
  	if (nlimbs) {
  		a->d = mpi_alloc_limb_space(nlimbs);
  		if (!a->d) {
  			kfree(a);
  			return NULL;
  		}
  	} else {
  		a->d = NULL;
  	}
  
  	a->alloced = nlimbs;
  	a->nlimbs = 0;
  	a->sign = 0;
  	a->flags = 0;
  	a->nbits = 0;
  	return a;
  }
  EXPORT_SYMBOL_GPL(mpi_alloc);
  
  mpi_ptr_t mpi_alloc_limb_space(unsigned nlimbs)
  {
  	size_t len = nlimbs * sizeof(mpi_limb_t);
  
  	if (!len)
  		return NULL;
  
  	return kmalloc(len, GFP_KERNEL);
  }
  
  void mpi_free_limb_space(mpi_ptr_t a)
  {
  	if (!a)
  		return;
  
  	kfree(a);
  }
  
  void mpi_assign_limb_space(MPI a, mpi_ptr_t ap, unsigned nlimbs)
  {
  	mpi_free_limb_space(a->d);
  	a->d = ap;
  	a->alloced = nlimbs;
  }
  
  /****************
   * Resize the array of A to NLIMBS. the additional space is cleared
   * (set to 0) [done by m_realloc()]
   */
  int mpi_resize(MPI a, unsigned nlimbs)
  {
  	void *p;
  
  	if (nlimbs <= a->alloced)
  		return 0;	/* no need to do it */
  
  	if (a->d) {
  		p = kmalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL);
  		if (!p)
  			return -ENOMEM;
  		memcpy(p, a->d, a->alloced * sizeof(mpi_limb_t));
  		kfree(a->d);
  		a->d = p;
  	} else {
  		a->d = kzalloc(nlimbs * sizeof(mpi_limb_t), GFP_KERNEL);
  		if (!a->d)
  			return -ENOMEM;
  	}
  	a->alloced = nlimbs;
  	return 0;
  }
  
  void mpi_free(MPI a)
  {
  	if (!a)
  		return;
  
  	if (a->flags & 4)
  		kfree(a->d);
  	else
  		mpi_free_limb_space(a->d);
  
  	if (a->flags & ~7)
  		pr_info("invalid flag value in mpi
  ");
  	kfree(a);
  }
  EXPORT_SYMBOL_GPL(mpi_free);
  
  MODULE_DESCRIPTION("Multiprecision maths library");
  MODULE_LICENSE("GPL");