From 8eef348ecabe1b3604b25288e5f96bb65cfe6e3f Mon Sep 17 00:00:00 2001
From: Nathan Cannon <neviynhd@gmail.com>
Date: Thu, 16 Nov 2017 17:07:52 +0000
Subject: [PATCH] Implemented memcpy and memset. Allows larger local variables.

---
 kernel/arch/i386/tty.nim |  4 ++--
 kernel/kernel.nim        | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/kernel/arch/i386/tty.nim b/kernel/arch/i386/tty.nim
index c7d3baf..5817093 100644
--- a/kernel/arch/i386/tty.nim
+++ b/kernel/arch/i386/tty.nim
@@ -65,9 +65,8 @@ proc terminalWrite*(data: string) =
 proc terminalWrite*(data: char) =
   terminalWriteChar(data)
 
-var parsedData: array[0..9, char]
-
 proc terminalWrite*(data: SomeSignedInt) =
+  var parsedData: array[0..9, char]
   if(data == 0):
     terminalWrite('0')
     return
@@ -86,6 +85,7 @@ proc terminalWrite*(data: SomeSignedInt) =
     terminalWrite(parsedData[i])
 
 proc terminalWrite*(data: SomeUnsignedInt) =
+  var parsedData: array[0..9, char]
   if(data == 0):
     terminalWrite('0')
     return
diff --git a/kernel/kernel.nim b/kernel/kernel.nim
index b4da3a8..d2c186e 100644
--- a/kernel/kernel.nim
+++ b/kernel/kernel.nim
@@ -3,6 +3,20 @@
 
 import tty, gdt, irq, serial
 
+type
+  MemoryPointer{.unchecked.} = ptr array[0, char]
+
+proc memcpy*(dest: ByteAddress, src: ByteAddress, count: int){.exportc.} =
+  var destMem = cast[MemoryPointer](dest)
+  var srcMem = cast[MemoryPointer](src)
+  for i in 0..count-1:
+    destMem[i] = srcMem[i]
+
+proc memset*(dest: ByteAddress, value: char, count: int){.exportc.} =
+  var destMem = cast[MemoryPointer](dest)
+  for i in 0..count-1:
+    destMem[i] = value
+
 proc kernelMain() {.exportc: "kernel_main"}=
   serial.init()
   serial.write("Booting OS\L")