Initial commit

3 files changed, 51 insertions, 0 deletions

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..5c48466
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,33 @@
+CC = gcc
+AS = as
+LD = ld
+
+CFLAGS = -c -nostdlib -fno-builtin
+ASFLAGS = -c
+
+LDFLAGS = -entry main -z noexecstack
+
+TARGET = helloworld
+OBJS = syscall.o helloworld.o
+
+all: $(TARGET)
+
+$(TARGET): $(OBJS)
+	$(LD) $(OBJS) $(LDFLAGS) -o $@
+
+helloworld.o: helloworld.c
+	$(CC) $(CFLAGS) $< -o $@
+
+syscall.o: syscall.s
+	$(AS) $(ASFLAGS) $< -o $@
+
+clean:
+	rm -f $(OBJS) $(TARGET)
+
+run: $(TARGET)
+	./$(TARGET)
+
+size: $(TARGET)
+	stat -c "%s bytes" $(TARGET)
+
+.PHONY: all clean run size
diff --git a/helloworld.c b/helloworld.c
new file mode 100644
index 0000000..5d89a54
--- /dev/null
+++ b/helloworld.c
@@ -0,0 +1,4 @@
+int main() {
+	write(1, "hello world", 12);
+	exit(0);
+}
diff --git a/syscall.s b/syscall.s
new file mode 100644
index 0000000..cf3cacb
--- /dev/null
+++ b/syscall.s
@@ -0,0 +1,14 @@
+.intel_syntax noprefix
+
+.global write
+.global exit
+
+
+write:
+	mov rax, 1
+	syscall
+	ret
+
+exit:
+    mov rax, 60
+    syscall