Create a program generating more complex ELF file

Makefile

@@ -14,7 +14,10 @@ bootloader/stage2.bin: force_look
 programs/one/a.out: force_look
 	cd programs/one; ${MAKE} a.out
 
-thor.flp: bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin programs/one/a.out
+programs/hello/a.out: force_look
+	cd programs/hello; ${MAKE} a.out
+
+thor.flp: bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin programs/one/a.out programs/hello/a.out
 	dd if=bootloader/stage1.bin of=hdd.img conv=notrunc
 	dd if=bootloader/stage2.bin of=hdd.img seek=1 conv=notrunc
 	sudo /sbin/losetup -o1048576 /dev/loop0 hdd.img
@@ -22,6 +25,7 @@ thor.flp: bootloader/stage1.bin bootloader/stage2.bin kernel/kernel.bin programs
 	sudo /bin/mount -t vfat /dev/loop0 /mnt/fake_cdrom/
 	sudo /bin/cp kernel/kernel.bin /mnt/fake_cdrom/
 	sudo /bin/cp programs/one/a.out /mnt/fake_cdrom/one
+	sudo /bin/cp programs/hello/a.out /mnt/fake_cdrom/hello
 	sleep 0.1
 	sudo /bin/umount /mnt/fake_cdrom/
 	sudo /sbin/losetup -d /dev/loop0

programs/hello/Makefile

@@ -0,0 +1,15 @@
+.PHONY: default clean
+
+default: a.out
+
+include ../../cpp.mk
+
+%.cpp.o: src/%.cpp
+	$(CC) $(CPP_FLAGS_64) $(WARNING_FLAGS) -c $< -o $@
+
+a.out: main.cpp.o
+	$(CC) $(COMMON_LINK_FLAGS) -e main $(CPP_FLAGS_64) -o a.out main.cpp.o
+
+clean:
+	rm *.cpp.o
+	rm -rf a.out

programs/hello/src/main.cpp

@@ -0,0 +1,38 @@
+//=======================================================================
+// Copyright Baptiste Wicht 2013.
+// Distributed under the Boost Software License, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt)
+//=======================================================================
+
+typedef unsigned int uint8_t __attribute__((__mode__(__QI__)));
+typedef unsigned int uint16_t __attribute__ ((__mode__ (__HI__)));
+typedef unsigned int uint32_t __attribute__ ((__mode__ (__SI__)));
+typedef unsigned int uint64_t __attribute__ ((__mode__ (__DI__)));
+
+const char* source = "Hello world";
+
+uint8_t make_color(uint8_t fg, uint8_t bg){
+    return fg | bg << 4;
+}
+
+uint16_t make_vga_entry(char c, uint8_t color){
+    uint16_t c16 = c;
+    uint16_t color16 = color;
+    return c16 | color16 << 8;
+}
+
+int main(){
+    uint16_t* vga_buffer = reinterpret_cast<uint16_t*>(0x0B8000);
+
+    auto s = source;
+    uint64_t i = 0;
+
+    while(*s){
+        vga_buffer[10 * 80 + 20 + i * 2] = make_vga_entry(*s, make_color(15, 0));
+        ++s;
+        ++i;
+    }
+
+    return 0;
+}