text: /*
   *
   * Copyright (c) 2016 Mytchel Hammond <mytchel@openmailbox.org>
   * 
   * Permission is hereby granted, free of charge, to any person
   * obtaining a copy of this software and associated documentation
   * files (the "Software"), to deal in the Software without
   * restriction, including without limitation the rights to use,
   * copy, modify, merge, publish, distribute, sublicense, and/or
   * sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following
   * conditions:
   * 
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   * 
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
   * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
   * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
   * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
   * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   *
   */
  
  #include "head.h"
  
  extern struct chantype devpipe, devfile;
  
  struct chantype *chantypes[CHAN_max] = {
    [CHAN_pipe] = &devpipe,
    [CHAN_file] = &devfile,
  };
  
  struct chan *
  channew(int type, int mode)
  {
    struct chan *c;
  	
    c = malloc(sizeof(struct chan));
    if (c == nil) {
      return nil;
    }
  
    c->refs = 1;
    c->type = type;
    c->mode = mode;
  
    return c;
  }
  
  void
  chanfree(struct chan *c)
  {
    if (atomicdec(&c->refs) > 0) {
      return;
    }
  
    chantypes[c->type]->close(c);
    free(c);
  }
  