Function pio_package_validation_json 

#[unsafe(no_mangle)]
pub unsafe extern "C" fn pio_package_validation_json(
    pkg: *const PioPackage,
    errbuf: *mut c_char,
    errlen: usize,
) -> *mut c_char

Return the package validation summary as JSON. The returned string is owned by the library; free it with pio_string_free.