fix tab -> 4spaces

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
surpress all warnings (use crash_if_err macro)

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
factor out split()

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
implement factory pattern

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>
add skelton

Signed-off-by: Akira Hayakawa <ruby.wktk@gmail.com>