offer hardlinking of files instead of full copy

copy.go

@@ -37,21 +37,33 @@ import (
 
 // Copy copies src to dest, doesn't matter if src is a directory or a file
 func Copy(src, dest string) error {
+	return run(src, dest, false)
+}
+
+func CopyDirsLinkFiles(src, dest string) error {
+	return run(src, dest, true)
+}
+
+func run(src, dest string, linkFiles bool) error {
 	info, err := os.Lstat(src)
 	if err != nil {
 		return err
 	}
-	return copy(src, dest, info)
+	return copy(src, dest, info, linkFiles)
 }
 
-func copy(src, dest string, info os.FileInfo) error {
+func copy(src, dest string, info os.FileInfo, linkFiles bool) error {
 	if info.Mode()&os.ModeSymlink != 0 {
 		return linkcopy(src, dest, info)
 	}
 	if info.IsDir() {
-		return dircopy(src, dest, info)
+		return dircopy(src, dest, info, linkFiles)
+	}
+	if !linkFiles {
+		return filecopy(src, dest, info)
+	} else {
+		return os.Link(src, dest)
 	}
-	return filecopy(src, dest, info)
 }
 
 func filecopy(src, dest string, info os.FileInfo) error {
@@ -78,7 +90,7 @@ func filecopy(src, dest string, info os.FileInfo) error {
 	return err
 }
 
-func dircopy(srcdir, destdir string, info os.FileInfo) error {
+func dircopy(srcdir, destdir string, info os.FileInfo, linkFiles bool) error {
 	if err := os.MkdirAll(destdir, info.Mode()); err != nil {
 		return err
 	}
@@ -88,7 +100,7 @@ func dircopy(srcdir, destdir string, info os.FileInfo) error {
 	}
 	for _, content := range contents {
 		cs, cd := filepath.Join(srcdir, content.Name()), filepath.Join(destdir, content.Name())
-		if err := copy(cs, cd, content); err != nil {
+		if err := copy(cs, cd, content, linkFiles); err != nil {
 			return err
 		}
 	}