Add elf and load it into kernel memory

src/elf.h

+/*
+  elf.h
+
+  Structures and symbols used for loading elf files
+*/
+
+#ifndef _ELF_INC
+#define _ELF_INT
+
+#include <stdint.h>
+
+extern uint8_t elf_hello[]  asm("_binary_hello_elf_start");
+
+#endif

src/kern.c

@@ -19,6 +19,7 @@
 #include "pic.h"
 #include "pit.h"
 #include "io.h"
+#include "elf.h"
 
 // The parameters passed here ultimately come through the bootloader
 void kernel_main(multiboot_info* mbt, uint32_t magic)
@@ -68,6 +69,12 @@ void kernel_main(multiboot_info* mbt, uint32_t magic)
     // PCI
     checkAllBuses();
 
+    // Elf testing
+    // This is defined in elf.h
+    serial_writestring("Elf address: 0x");
+    serial_hexstring(elf_hello, 4);
+    serial_writestring("\n");
+
     test_idt();
     while(true)
     {

src/makefile

@@ -5,7 +5,7 @@ all:
 	/usr/bin/nasm -felf32 paging.asm
 	/usr/bin/nasm -felf32 idta.asm
 	$C *.c -std=gnu99 -ffreestanding -O2 -Wall -Wextra -c
-	$C -T linker.ld -o myos.bin -ffreestanding -O2 -nostdlib *.o -lgcc
+	$C -Wl,--format=binary -Wl,hello.elf -Wl,--format=default -T linker.ld -o myos.bin -ffreestanding -O2 -nostdlib *.o -lgcc
 
 clean:
 	rm *.o *.bin