Implement Default for CStr and CString and add constructor to CString

src/raw/cstr.rs

@@ -92,6 +92,12 @@ impl CStr {
     }
 }
 
+impl Default for &CStr {
+    fn default() -> Self {
+        cstr!("")
+    }
+}
+
 impl PartialEq for CStr {
     fn eq(&self, other: &CStr) -> bool {
         self.as_str() == other.as_str()
@@ -233,7 +239,7 @@ pub use cstr;
 ///
 /// Like `CStr`, this differs from [`std::ffi::CString`] in that it is required to be valid UTF-8,
 /// and does not include the nul terminator in the buffer.
-#[derive(Clone, Eq)]
+#[derive(Clone, Eq, Default)]
 #[repr(transparent)]
 pub struct CString {
     data: String,
@@ -258,6 +264,11 @@ impl TryFrom<&str> for CString {
 }
 
 impl CString {
+    /// Creates a new empty `CString`.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
     pub(crate) fn from_string_unchecked(data: String) -> Self {
         Self { data }
     }