summaryrefslogtreecommitdiffstats
path: root/arch/um/drivers/null.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/um/drivers/null.c')
-rw-r--r--arch/um/drivers/null.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/um/drivers/null.c b/arch/um/drivers/null.c
new file mode 100644
index 0000000..14cc5f7
--- /dev/null
+++ b/arch/um/drivers/null.c
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include "chan_user.h"
+#include "os.h"
+
+static int null_chan;
+
+static void *null_init(char *str, int device, struct chan_opts *opts)
+{
+ return(&null_chan);
+}
+
+static int null_open(int input, int output, int primary, void *d,
+ char **dev_out)
+{
+ *dev_out = NULL;
+ return(os_open_file(DEV_NULL, of_rdwr(OPENFLAGS()), 0));
+}
+
+static int null_read(int fd, char *c_out, void *unused)
+{
+ return(-ENODEV);
+}
+
+static void null_free(void *data)
+{
+}
+
+struct chan_ops null_ops = {
+ .type = "null",
+ .init = null_init,
+ .open = null_open,
+ .close = generic_close,
+ .read = null_read,
+ .write = generic_write,
+ .console_write = generic_console_write,
+ .window_size = generic_window_size,
+ .free = null_free,
+ .winch = 0,
+};
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
OpenPOWER on IntegriCloud