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.

1 files changed, 158 insertions, 0 deletions

diff --git a/c/src/exec/libfs/src/imfs/imfs_initsupp.c b/c/src/exec/libfs/src/imfs/imfs_initsupp.c
new file mode 100644
index 0000000000..bb3a0f9aea
--- /dev/null
+++ b/c/src/exec/libfs/src/imfs/imfs_initsupp.c
@@ -0,0 +1,158 @@
+/*
+ *  IMFS Initialization
+ *
+ *  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>         /* for mkdir */
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+#include <assert.h>
+
+#include "imfs.h"
+#include "libio_.h"
+
+#if defined(IMFS_DEBUG)
+#include <stdio.h>
+#endif
+
+/*
+ *  IMFS file system operations table
+ */
+
+rtems_filesystem_operations_table  IMFS_ops = {
+  IMFS_eval_path,
+  IMFS_evaluate_for_make,
+  IMFS_link,
+  IMFS_unlink,
+  IMFS_node_type,
+  IMFS_mknod,
+  IMFS_rmnod,
+  IMFS_chown,
+  IMFS_freenodinfo,
+  IMFS_mount,
+  IMFS_initialize,
+  IMFS_unmount,
+  IMFS_fsunmount,
+  IMFS_utime, 
+  IMFS_evaluate_link,
+  IMFS_symlink,
+  IMFS_readlink
+};
+
+/*
+ *  IMFS_initialize
+ */
+
+int IMFS_initialize(
+  rtems_filesystem_mount_table_entry_t *temp_mt_entry
+)
+{
+  IMFS_fs_info_t                        *fs_info;
+  IMFS_jnode_t                          *jnode;
+
+  /*
+   *  Create the root node
+   */
+
+  temp_mt_entry->mt_fs_root.node_access = IMFS_create_node(
+    NULL,
+    IMFS_DIRECTORY,
+    "",
+    ( S_IRWXO | S_IRWXG| S_IRWXU ),
+    NULL
+  );
+
+  temp_mt_entry->mt_fs_root.handlers    = &dir_handlers;
+  temp_mt_entry->mt_fs_root.ops         = &IMFS_ops;
+  temp_mt_entry->pathconf_limits_and_options = IMFS_LIMITS_AND_OPTIONS;
+
+  /*
+   * Create custom file system data.
+   */
+  fs_info = calloc( 1, sizeof( IMFS_fs_info_t ) );
+  if ( !fs_info ){
+    free(temp_mt_entry->mt_fs_root.node_access);
+    return 1;
+  }
+  temp_mt_entry->fs_info = fs_info;
+
+  /*
+   * Set st_ino for the root to 1.
+   */
+
+  fs_info->ino_count   = 1;
+
+  jnode = temp_mt_entry->mt_fs_root.node_access;
+  jnode->st_ino = fs_info->ino_count;
+
+  return 0;
+}
+
+#define jnode_get_control( jnode ) \
+  (&jnode->info.directory.Entries)
+
+#define jnode_has_no_children( jnode )  \
+  Chain_Is_empty( jnode_get_control( jnode ) )
+
+#define jnode_has_children( jnode ) \
+  ( ! jnode_has_no_children( jnode ) )
+
+#define jnode_get_first_child( jnode ) \
+    ((IMFS_jnode_t *)( Chain_Head( jnode_get_control( jnode ) )->next))
+
+
+int IMFS_fsunmount(
+  rtems_filesystem_mount_table_entry_t *temp_mt_entry
+)
+{
+   IMFS_jnode_t                     *jnode;
+   IMFS_jnode_t                     *next;
+   rtems_filesystem_location_info_t loc;       
+   int                              result = 0;
+
+   /* 
+    * Traverse tree that starts at the mt_fs_root and deallocate memory 
+    * associated memory space
+    */
+    
+   jnode = (IMFS_jnode_t *)temp_mt_entry->mt_fs_root.node_access;
+
+   do {
+     next = jnode->Parent;
+     loc.node_access = (void *)jnode;
+
+     if ( jnode->type != IMFS_DIRECTORY ) {
+        result = IMFS_unlink( &loc );
+        if (result != 0)
+          return -1;
+        jnode = next;
+     } else if ( jnode_has_no_children( jnode ) ) {
+        result = IMFS_unlink( &loc );
+        if (result != 0)
+          return -1;
+        jnode = next;
+     }
+     if ( jnode != NULL ) {
+       if ( jnode->type == IMFS_DIRECTORY ) {
+         if ( jnode_has_children( jnode ) )
+           jnode = jnode_get_first_child( jnode );
+       }
+     }
+   } while (jnode != NULL);
+
+   return 0;
+}
+
+
+