Implemented ELF header

build/Build.go

@@ -1,6 +1,12 @@
 package build
 
-import "path/filepath"
+import (
+	"bufio"
+	"os"
+	"path/filepath"
+
+	"git.akyoto.dev/cli/q/build/elf"
+)
 
 // Build describes a compiler build.
 type Build struct {
@@ -30,5 +36,37 @@ func New(directory string) (*Build, error) {
 
 // Run parses the input files and generates an executable file.
 func (build *Build) Run() error {
+	if build.WriteExecutable {
+		sampleCode := []byte{
+			0xb8, 0x3c, 0x00, 0x00, 0x00, // mov rax, 60
+			0xbf, 0x00, 0x00, 0x00, 0x00, // mov rdi, 0
+			0x0f, 0x05, // syscall
+		}
+
+		return writeToDisk(build.ExecutablePath, sampleCode, nil)
+	}
+
 	return nil
 }
+
+// writeToDisk writes the executable file to disk.
+func writeToDisk(filePath string, code []byte, data []byte) error {
+	file, err := os.Create(filePath)
+
+	if err != nil {
+		return err
+	}
+
+	buffer := bufio.NewWriter(file)
+	executable := elf.New()
+	executable.Write(buffer)
+	buffer.Flush()
+
+	err = file.Close()
+
+	if err != nil {
+		return err
+	}
+
+	return os.Chmod(filePath, 0755)
+}