1 files changed, 76 insertions, 0 deletions
diff --git a/libstore/file.c b/libstore/file.c
new file mode 100644
index 00000000..4bf16432
--- /dev/null
+++ b/libstore/file.c
@@ -0,0 +1,76 @@
+/* Mach file store backend
+
+   Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+
+   Written by Miles Bader <miles@gnu.ai.mit.edu>
+
+   This file is part of the GNU Hurd.
+
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU General Public License as
+   published by the Free Software Foundation; either version 2, or (at
+   your option) any later version.
+
+   The GNU Hurd is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+#include <assert.h>
+
+#include "store.h"
+
+static error_t
+file_read (struct store *store, off_t addr, mach_msg_type_number_t amount,
+	  char **buf, mach_msg_type_number_t *len)
+{
+  return io_read (store->port, buf, len, addr * store->block_size, amount);
+}
+
+static error_t
+file_write (struct store *store,
+	   off_t addr, char *buf, mach_msg_type_number_t len,
+	   mach_msg_type_number_t *amount)
+{
+  return io_write (store->port, buf, len, addr * store->block_size, amount);
+}
+
+static struct store_meths
+file_meths = {dev_read, dev_write};
+
+/* Return a new store in STORE referring to the mach file FILE.  Consumes
+   the send right FILE.  */
+error_t
+store_file_create (file_t file, struct store **store)
+{
+  off_t runs[2];
+  size_t sizes[DEV_GET_SIZE_COUNT], block_size;
+  unsigned sizes_len = DEV_GET_SIZE_COUNT;
+  error_t err = file_get_status (file, DEV_GET_SIZE, sizes, &sizes_len);
+
+  if (err)
+    return err;
+
+  assert (sizes_len == DEV_GET_SIZE_COUNT);
+
+  block_size = sizes[DEV_GET_SIZE_RECORD_SIZE];
+  runs[0] = 0;
+  runs[1] = sizes[DEV_GET_SIZE_FILE_SIZE] / block_size;
+
+  return _store_file_create (file, runs, 2, block_size, store);
+}
+
+/* Like store_file_create, but doesn't query the file for information.   */
+error_t
+_store_file_create (file_t file,
+		      off_t *runs, unsigned runs_len, size_t block_size,
+		      struct store **store)
+{
+  *store = _make_store (STORAGE_FILE, &file_meths, file, block_size,
+			runs, runs_len);
+  return *store ? 0 : ENOMEM;
+}