Added base version of file system infrastructure. This includes a major

overhaul of the RTEMS system call interface.  This base file system is
the "In-Memory File System" aka IMFS.

The design and implementation was done by the following people:

  + Joel Sherrill (joel@OARcorp.com)
  + Jennifer Averett (jennifer@OARcorp.com)
  + Steve "Mr Mount" Salitasc (salitasc@OARcorp.com)
  + Kerwin Wade (wade@OARcorp.com)

PROBLEMS
========
  + It is VERY likely that merging this will break the UNIX port.  This
    can/will be fixed.

  + There is likely some reentrancy/mutual exclusion needed.

  + Eventually, there should be a "mini-IMFS" description table to
    eliminate links, symlinks, etc to save memory.  All you need to
    have "classic RTEMS" functionality is technically directories
    and device IO.  All the rest could be left out to save memory.

c/src/lib/libc/ioman.c

@@ -0,0 +1,83 @@
+/*
+ *  This file emulates the old Classic RTEMS IO manager directives
+ *  which register and lookup names using the in-memory filesystem.
+ *
+ *  COPYRIGHT (c) 1989-1998.
+ *  On-Line Applications Research Corporation (OAR).
+ *  Copyright assigned to U.S. Government, 1994.
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.OARcorp.com/rtems/license.html.
+ *
+ *  $Id$
+ */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <assert.h>
+
+#include <rtems.h>
+#include "libio_.h"
+#include "imfs.h"
+
+/* 
+ *  rtems_io_register_name
+ *
+ *  This assumes that all registered devices are character devices.
+ */
+
+rtems_status_code rtems_io_register_name(
+  char *device_name,
+  rtems_device_major_number major,
+  rtems_device_minor_number minor
+)
+{
+  int    status;
+  dev_t  dev;
+
+  dev = rtems_filesystem_make_dev_t( major, minor );
+  status = mknod( device_name, 0777 | S_IFCHR, dev );
+
+  /* this is the only error returned by the old version */
+  if ( status )
+    return RTEMS_TOO_MANY;
+ 
+  return RTEMS_SUCCESSFUL;
+}
+
+/* 
+ *  rtems_io_lookup_name
+ *
+ *  This version is not reentrant.
+ */
+
+rtems_status_code rtems_io_lookup_name(
+  const char           *name,
+  rtems_driver_name_t **device_info
+)
+{
+  IMFS_jnode_t                      *the_jnode;
+  rtems_filesystem_location_info_t   temp_loc;
+  static rtems_driver_name_t         device;
+  int                                result;
+
+  result = rtems_filesystem_evaluate_path( name, 0x00, &temp_loc, TRUE );
+  the_jnode = temp_loc.node_access;
+
+  if ( (result != 0) || the_jnode->type != IMFS_DEVICE ) {
+    *device_info = 0;
+    return RTEMS_UNSATISFIED;
+  }
+
+  device.device_name        = (char *) name;
+  device.device_name_length = strlen( name );
+  device.major              = the_jnode->info.device.major;
+  device.minor              = the_jnode->info.device.minor;
+  *device_info              = &device;
+  return RTEMS_SUCCESSFUL;
+
+}