From bebee434eecc8e894ce725da842067d800672f0b Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Thu, 14 Jun 2012 16:41:40 +0800
Subject: [PATCH] Kernel - Added /Devices/{zero,one,null}

---
 KernelLand/Kernel/Makefile       |   2 +-
 KernelLand/Kernel/drv/zero-one.c | 101 +++++++++++++++++++++++++++++++
 2 files changed, 102 insertions(+), 1 deletion(-)
 create mode 100644 KernelLand/Kernel/drv/zero-one.c

diff --git a/KernelLand/Kernel/Makefile b/KernelLand/Kernel/Makefile
index 81a29285..a5a5c03f 100644
--- a/KernelLand/Kernel/Makefile
+++ b/KernelLand/Kernel/Makefile
@@ -54,7 +54,7 @@ OBJ := $(addprefix arch/$(ARCHDIR)/,$(A_OBJ))
 OBJ += heap.o drvutil.o logging.o debug.o lib.o adt.o time.o
 OBJ += messages.o modules.o syscalls.o system.o
 OBJ += threads.o mutex.o semaphore.o workqueue.o events.o
-OBJ += drv/proc.o drv/fifo.o drv/iocache.o drv/pci.o
+OBJ += drv/zero-one.o drv/proc.o drv/fifo.o drv/iocache.o drv/pci.o
 OBJ += drv/vterm.o drv/vterm_font.o drv/vterm_vt100.o drv/vterm_output.o drv/vterm_input.o drv/vterm_termbuf.o
 OBJ += binary.o bin/elf.o bin/pe.o
 OBJ += vfs/main.o vfs/open.o vfs/acls.o vfs/dir.o vfs/io.o vfs/mount.o
diff --git a/KernelLand/Kernel/drv/zero-one.c b/KernelLand/Kernel/drv/zero-one.c
new file mode 100644
index 00000000..824f9276
--- /dev/null
+++ b/KernelLand/Kernel/drv/zero-one.c
@@ -0,0 +1,101 @@
+/*
+ * Acess2 Kernel
+ * - By John Hodge (thePowersGang)
+ *
+ * drv/zero-one.c
+ * - /Devices/{null,zero,one}
+ */
+#define DEBUG	0
+#include <acess.h>
+#include <modules.h>
+#include <fs_devfs.h>
+
+// === PROTOTYPES ===
+ int	CoreDevs_Install(char **Arguments);
+size_t	CoreDevs_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void *Buffer);
+size_t	CoreDevs_Read_Zero(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer);
+size_t	CoreDevs_Read_One (tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer);
+size_t	CoreDevs_Read_Null(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer);
+
+// === GLOBALS ===
+MODULE_DEFINE(0, 0x0100, CoreDevs, CoreDevs_Install, NULL, NULL);
+tVFS_NodeType	gCoreDevs_NT_Null = {
+	.TypeName = "CoreDevs-null",
+	.Read  = CoreDevs_Read_Null,
+	.Write = CoreDevs_Write
+};
+tVFS_NodeType	gCoreDevs_NT_Zero = {
+	.TypeName = "CoreDevs-zero",
+	.Read  = CoreDevs_Read_Zero,
+	.Write = CoreDevs_Write
+};
+tVFS_NodeType	gCoreDevs_NT_One = {
+	.TypeName = "CoreDevs-one",
+	.Read  = CoreDevs_Read_One,
+	.Write = CoreDevs_Write
+};
+tDevFS_Driver	gCoreDevs_Null = {
+	NULL, "null",
+	{
+	.Size = 0,
+	.NumACLs = 1,
+	.ACLs = &gVFS_ACL_EveryoneRW,
+	.Type = &gCoreDevs_NT_Null
+	}
+};
+tDevFS_Driver	gCoreDevs_Zero = {
+	NULL, "zero",
+	{
+	.Size = 0,
+	.NumACLs = 1,
+	.ACLs = &gVFS_ACL_EveryoneRW,
+	.Type = &gCoreDevs_NT_Zero
+	}
+};
+tDevFS_Driver	gCoreDevs_One = {
+	NULL, "one",
+	{
+	.Size = 0,
+	.NumACLs = 1,
+	.ACLs = &gVFS_ACL_EveryoneRW,
+	.Type = &gCoreDevs_NT_One
+	}
+};
+
+// === CODE ===
+/**
+ * \brief Installs the CoreDevs driver
+ */
+int CoreDevs_Install(char **Options)
+{
+	DevFS_AddDevice( &gCoreDevs_Null );
+	DevFS_AddDevice( &gCoreDevs_Zero );
+	DevFS_AddDevice( &gCoreDevs_One  );
+	return MODULE_ERR_OK;
+}
+
+size_t CoreDevs_Write(tVFS_Node *Node, off_t Offset, size_t Length, const void *Buffer)
+{
+	return Length;	// Ignore
+}
+
+size_t CoreDevs_Read_Zero(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
+{
+	memset(Buffer, 0, Length);
+	return Length;
+}
+
+size_t CoreDevs_Read_One (tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
+{
+	Uint8	*ptr = Buffer;
+	size_t	rem;
+	for( rem = Length; rem --; ptr ++ )
+		*ptr = 0xFF;
+	return Length;
+}
+
+size_t CoreDevs_Read_Null(tVFS_Node *Node, off_t Offset, size_t Length, void *Buffer)
+{
+	return 0;
+}
+
-- 
2.20.1