Split input and output sides of the device model

1 files changed, 53 insertions, 0 deletions

diff --git a/com32/lib/sys/null_read.c b/com32/lib/sys/null_read.c
new file mode 100644
index 00000000..8121faee
--- /dev/null
+++ b/com32/lib/sys/null_read.c
@@ -0,0 +1,53 @@
+#ident "$Id$"
+/* ----------------------------------------------------------------------- *
+ *   
+ *   Copyright 2004 H. Peter Anvin - All Rights Reserved
+ *
+ *   Permission is hereby granted, free of charge, to any person
+ *   obtaining a copy of this software and associated documentation
+ *   files (the "Software"), to deal in the Software without
+ *   restriction, including without limitation the rights to use,
+ *   copy, modify, merge, publish, distribute, sublicense, and/or
+ *   sell copies of the Software, and to permit persons to whom
+ *   the Software is furnished to do so, subject to the following
+ *   conditions:
+ *   
+ *   The above copyright notice and this permission notice shall
+ *   be included in all copies or substantial portions of the Software.
+ *   
+ *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *   OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *   HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *   WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *   FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *   OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * null_read.c
+ *
+ * Reading null device
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <com32.h>
+#include <minmax.h>
+#include "file.h"
+
+static ssize_t __null_read(struct file_info *fp, void *buf, size_t count)
+{
+  (void)fp; (void)buf; (void)count;
+  return 0;
+}
+
+const struct input_dev dev_null_r = {
+  .dev_magic = __DEV_MAGIC,
+  .flags     = __DEV_INPUT | __DEV_NULL,
+  .fileflags = O_RDONLY,
+  .read      = __null_read,
+  .close     = NULL,
+};