de2-115-fpga-pong/software/hello_world_bsp/HAL/src/alt_fs_reg.c

/******************************************************************************
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* License Agreement                                                           *
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* Copyright (c) 2004 Altera Corporation, San Jose, California, USA.           *
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#include <errno.h>

#include "sys/alt_dev.h"
#include "priv/alt_file.h"

/*
 * The alt_fs_reg() function is used to register a file system. Once registered 
 * a device can be accessed using the standard posix calls: open(), read(), 
 * write() etc.
 *
 * System behaviour is undefined in the event that a file system is registered 
 * with a name that conflicts with an existing device or file system.
 *
 * alt_fs_reg() is not thread safe in the sense that there should be no other 
 * thread using the file system list at the time that alt_dev_reg() is called. In
 * practice this means that alt_fs_reg() should only be called while operating
 * in a single threaded mode. The expectation is that it will only be called
 * by the file system initilisation functions invoked by alt_sys_init(), which in 
 * turn should only be called by the single threaded C startup code.   
 *
 * A return value of zero indicates success. A negative return value indicates
 * failure. 
 */
 
int alt_fs_reg (alt_dev* dev)
{
  /*
   * check that the device has a name.
   */

  if (!dev->name)
  {
    return -ENODEV;
  }
  
  /*
   * register the file system.
   */

  alt_llist_insert(&alt_fs_list, &dev->llist);

  return 0;
}