Filesystem: Reference counting for locations

 o A new data structure rtems_filesystem_global_location_t was
   introduced to be used for
    o the mount point location in the mount table entry,
    o the file system root location in the mount table entry,
    o the root directory location in the user environment, and
    o the current directory location in the user environment.
   During the path evaluation global start locations are obtained to
   ensure that the current file system instance will be not unmounted in
   the meantime.
 o The user environment uses now reference counting and is protected
   from concurrent access.
 o The path evaluation process was completely rewritten and simplified.
   The IMFS, RFS, NFS, and DOSFS use now a generic path evaluation
   method.  Recursive calls in the path evaluation have been replaced
   with iteration to avoid stack overflows.  Only the evaluation of
   symbolic links is recursive.  No dynamic memory allocations and
   intermediate buffers are used in the high level path evaluation.  No
   global locks are held during the file system instance specific path
   evaluation process.
 o Recursive symbolic link evaluation is now limited by
   RTEMS_FILESYSTEM_SYMLOOP_MAX.  Applications can retrieve this value
   via sysconf().
 o The device file system (devFS) uses now no global variables and
   allocation from the workspace.  Node names are allocated from the
   heap.
 o The upper layer lseek() performs now some parameter checks.
 o The upper layer ftruncate() performs now some parameter checks.
 o unmask() is now restricted to the RWX flags and protected from
   concurrent access.
 o The fchmod_h and rmnod_h file system node handlers are now a file
   system operation.
 o The unlink_h operation has been removed.  All nodes are now destroyed
   with the rmnod_h operation.
 o New lock_h, unlock_h, clonenod_h, and are_nodes_equal_h file system
   operations.
 o The path evaluation and file system operations are now protected by
   per file system instance lock and unlock operations.
 o Fix and test file descriptor duplicate in fcntl().
 o New test fstests/fsnofs01.

1 files changed, 45 insertions, 62 deletions

diff --git a/cpukit/libnetworking/lib/ftpfs.c b/cpukit/libnetworking/lib/ftpfs.c
index e588bc41ad..b50890e4c9 100644
--- a/cpukit/libnetworking/lib/ftpfs.c
+++ b/cpukit/libnetworking/lib/ftpfs.c
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (c) 2009, 2010, 2011
+ * Copyright (c) 2009-2012
  * embedded brains GmbH
  * Obere Lagerstr. 30
  * D-82178 Puchheim
@@ -54,7 +54,7 @@
 #include <rtems.h>
 #include <rtems/ftpfs.h>
 #include <rtems/imfs.h>
-#include <rtems/libio.h>
+#include <rtems/libio_.h>
 #include <rtems/rtems_bsdnet.h>
 #include <rtems/seterr.h>
 
@@ -939,8 +939,8 @@ static int rtems_ftpfs_open_data_connection_passive(
 static int rtems_ftpfs_open(
   rtems_libio_t *iop,
   const char *path,
-  uint32_t flags,
-  uint32_t mode
+  int oflag,
+  mode_t mode
 )
 {
   int eno = 0;
@@ -962,11 +962,6 @@ static int rtems_ftpfs_open(
   /* Invalidate data handle */
   iop->data1 = NULL;
 
-  /* Check location, it was allocated during path evaluation */
-  if (location == NULL) {
-    rtems_set_errno_and_return_minus_one(ENOMEM);
-  }
-
   /* Split location into parts */
   ok = rtems_ftpfs_split_names(
       location,
@@ -976,17 +971,7 @@ static int rtems_ftpfs_open(
       &filename
   );
   if (!ok) {
-    if (strlen(location) == 0) {
-      /*
-       * This is an access to the root node that will be used for file system
-       * option settings.
-       */
-      iop->pathinfo.handlers = &rtems_ftpfs_root_handlers;
-
-      return 0;
-    } else {
-      rtems_set_errno_and_return_minus_one(ENOENT);
-    }
+    rtems_set_errno_and_return_minus_one(ENOENT);
   }
   DEBUG_PRINTF(
     "user = '%s', password = '%s', filename = '%s'\n",
@@ -1154,39 +1139,40 @@ static int rtems_ftpfs_ftruncate(rtems_libio_t *iop, off_t count)
   return 0;
 }
 
-static int rtems_ftpfs_eval_path(
-  const char *pathname,
-  size_t pathnamelen,
-  int flags,
-  rtems_filesystem_location_info_t *pathloc
+static void rtems_ftpfs_eval_path(
+  rtems_filesystem_eval_path_context_t *self
 )
 {
-  /*
-   * The caller of this routine has striped off the mount prefix from the path.
-   * We need to store this path here or otherwise we would have to do this job
-   * again.  The path is used in rtems_ftpfs_open() via iop->pathinfo.node_access.
-   */
-  char *pathname_dup = malloc(pathnamelen + 1);
+  rtems_filesystem_eval_path_eat_delimiter(self);
 
-  if (pathname_dup != NULL) {
-    memcpy(pathname_dup, pathname, pathnamelen);
-    pathname_dup [pathnamelen] = '\0';
-  }
+  if (rtems_filesystem_eval_path_has_path(self)) {
+    const char *path = rtems_filesystem_eval_path_get_path(self);
+    size_t pathlen = rtems_filesystem_eval_path_get_pathlen(self);
+    char *pathdup = malloc(pathlen + 1);
 
-  pathloc->node_access = pathname_dup;
+    rtems_filesystem_eval_path_clear_path(self);
 
-  return 0;
+    if (pathdup != NULL) {
+      rtems_filesystem_location_info_t *currentloc =
+        rtems_filesystem_eval_path_get_currentloc(self);
+
+      memcpy(pathdup, path, pathlen);
+      pathdup [pathlen] = '\0';
+      currentloc->node_access = pathdup;
+      currentloc->handlers = &rtems_ftpfs_handlers;
+    } else {
+      rtems_filesystem_eval_path_error(self, ENOMEM);
+    }
+  }
 }
 
-static int rtems_ftpfs_free_node(rtems_filesystem_location_info_t *pathloc)
+static void rtems_ftpfs_free_node(const rtems_filesystem_location_info_t *loc)
 {
-  free(pathloc->node_access);
-
-  return 0;
+  free(loc->node_access);
 }
 
 static rtems_filesystem_node_types_t rtems_ftpfs_node_type(
-  rtems_filesystem_location_info_t *pathloc
+  const rtems_filesystem_location_info_t *loc
 )
 {
   return RTEMS_FILESYSTEM_MEMORY_FILE;
@@ -1209,11 +1195,11 @@ int rtems_ftpfs_initialize(
   me->timeout.tv_usec = 0;
 
   /* Set handler and oparations table */
-  e->mt_fs_root.handlers = &rtems_ftpfs_handlers;
-  e->mt_fs_root.ops = &rtems_ftpfs_ops;
+  e->mt_fs_root->location.handlers = &rtems_ftpfs_root_handlers;
+  e->mt_fs_root->location.ops = &rtems_ftpfs_ops;
 
   /* We maintain no real file system nodes, so there is no real root */
-  e->mt_fs_root.node_access = NULL;
+  e->mt_fs_root->location.node_access = NULL;
 
   /* Just use the limits from IMFS */
   e->pathconf_limits_and_options = IMFS_LIMITS_AND_OPTIONS;
@@ -1221,13 +1207,11 @@ int rtems_ftpfs_initialize(
   return 0;
 }
 
-static int rtems_ftpfs_unmount_me(
+static void rtems_ftpfs_unmount_me(
   rtems_filesystem_mount_table_entry_t *e
 )
 {
   free(e->fs_info);
-
-  return 0;
 }
 
 static int rtems_ftpfs_ioctl(
@@ -1271,14 +1255,12 @@ static int rtems_ftpfs_ioctl(
  * a remote to remote copy.  This is not a very sophisticated method.
  */
 static int rtems_ftpfs_fstat(
-  rtems_filesystem_location_info_t *loc,
+  const rtems_filesystem_location_info_t *loc,
   struct stat *st
 )
 {
   static unsigned ino = 0;
 
-  memset(st, 0, sizeof(*st));
-
   /* FIXME */
   st->st_ino = ++ino;
   st->st_dev = rtems_filesystem_make_dev_t(0xcc494cd6U, 0x1d970b4dU);
@@ -1289,22 +1271,27 @@ static int rtems_ftpfs_fstat(
 }
 
 static const rtems_filesystem_operations_table rtems_ftpfs_ops = {
-  .evalpath_h = rtems_ftpfs_eval_path,
-  .evalformake_h = rtems_filesystem_default_evalformake,
+  .lock_h = rtems_filesystem_default_lock,
+  .unlock_h = rtems_filesystem_default_unlock,
+  .eval_path_h = rtems_ftpfs_eval_path,
   .link_h = rtems_filesystem_default_link,
-  .unlink_h = rtems_filesystem_default_unlink,
+  .are_nodes_equal_h = rtems_filesystem_default_are_nodes_equal,
   .node_type_h = rtems_ftpfs_node_type,
   .mknod_h = rtems_filesystem_default_mknod,
+  .rmnod_h = rtems_filesystem_default_rmnod,
+  .fchmod_h = rtems_filesystem_default_fchmod,
   .chown_h = rtems_filesystem_default_chown,
+  .clonenod_h = rtems_filesystem_default_clonenode,
   .freenod_h = rtems_ftpfs_free_node,
   .mount_h = rtems_filesystem_default_mount,
   .fsmount_me_h = rtems_ftpfs_initialize,
   .unmount_h = rtems_filesystem_default_unmount,
   .fsunmount_me_h = rtems_ftpfs_unmount_me,
   .utime_h = rtems_filesystem_default_utime,
-  .eval_link_h = rtems_filesystem_default_evaluate_link,
   .symlink_h = rtems_filesystem_default_symlink,
-  .readlink_h = rtems_filesystem_default_readlink
+  .readlink_h = rtems_filesystem_default_readlink,
+  .rename_h = rtems_filesystem_default_rename,
+  .statvfs_h = rtems_filesystem_default_statvfs
 };
 
 static const rtems_filesystem_file_handlers_r rtems_ftpfs_handlers = {
@@ -1315,12 +1302,10 @@ static const rtems_filesystem_file_handlers_r rtems_ftpfs_handlers = {
   .ioctl_h = rtems_filesystem_default_ioctl,
   .lseek_h = rtems_filesystem_default_lseek,
   .fstat_h = rtems_ftpfs_fstat,
-  .fchmod_h = rtems_filesystem_default_fchmod,
   .ftruncate_h = rtems_ftpfs_ftruncate,
   .fsync_h = rtems_filesystem_default_fsync,
   .fdatasync_h = rtems_filesystem_default_fdatasync,
-  .fcntl_h = rtems_filesystem_default_fcntl,
-  .rmnod_h = rtems_filesystem_default_rmnod
+  .fcntl_h = rtems_filesystem_default_fcntl
 };
 
 static const rtems_filesystem_file_handlers_r rtems_ftpfs_root_handlers = {
@@ -1331,10 +1316,8 @@ static const rtems_filesystem_file_handlers_r rtems_ftpfs_root_handlers = {
   .ioctl_h = rtems_ftpfs_ioctl,
   .lseek_h = rtems_filesystem_default_lseek,
   .fstat_h = rtems_filesystem_default_fstat,
-  .fchmod_h = rtems_filesystem_default_fchmod,
   .ftruncate_h = rtems_filesystem_default_ftruncate,
   .fsync_h = rtems_filesystem_default_fsync,
   .fdatasync_h = rtems_filesystem_default_fdatasync,
-  .fcntl_h = rtems_filesystem_default_fcntl,
-  .rmnod_h = rtems_filesystem_default_rmnod
+  .fcntl_h = rtems_filesystem_default_fcntl
 };