text: /*
   * Copyright (c) 2003 Matteo Frigo
   * Copyright (c) 2003 Massachusetts Institute of Technology
   *
   * This program 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.
   *
   * This program 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 "ifftw.h"
  
  /*
    common routines for Rader solvers 
  */
  
  
  /* shared twiddle and omega lists, keyed by two/three integers. */
  struct rader_tls {
       int k1, k2, k3;
       R *W;
       int refcnt;
       rader_tl *cdr; 
  };
  
  void X(rader_tl_insert)(int k1, int k2, int k3, R *W, rader_tl **tl)
  {
       rader_tl *t = (rader_tl *) MALLOC(sizeof(rader_tl), TWIDDLES);
       t->k1 = k1; t->k2 = k2; t->k3 = k3; t->W = W;
       t->refcnt = 1; t->cdr = *tl; *tl = t;
  }
  
  R *X(rader_tl_find)(int k1, int k2, int k3, rader_tl *t)
  {
       while (t && (t->k1 != k1 || t->k2 != k2 || t->k3 != k3))
  	  t = t->cdr;
       if (t) {
  	  ++t->refcnt;
  	  return t->W;
       } else 
  	  return 0;
  }
  
  void X(rader_tl_delete)(R *W, rader_tl **tl)
  {
       if (W) {
  	  rader_tl **tp, *t;
  
  	  for (tp = tl; (t = *tp) && t->W != W; tp = &t->cdr)
  	       ;
  
  	  if (t && --t->refcnt <= 0) {
  	       *tp = t->cdr;
  	       X(ifree)(t->W);
  	       X(ifree)(t);
  	  }
       }
  }
  