eekkey: Moved state to KeyState

src/util.rs

@@ -0,0 +1,49 @@
+pub mod c {
+    use std::ffi::{ CStr, CString };
+    use std::os::raw::c_char;
+    use std::str::Utf8Error;
+    
+    pub fn as_str(s: &*const c_char) -> Result<Option<&str>, Utf8Error> {
+        if s.is_null() {
+            Ok(None)
+        } else {
+            unsafe {CStr::from_ptr(*s)}
+                .to_str()
+                .map(Some)
+        }
+    }
+    
+    pub fn as_cstr(s: &*const c_char) -> Option<&CStr> {
+        if s.is_null() {
+            None
+        } else {
+            Some(unsafe {CStr::from_ptr(*s)})
+        }
+    }
+
+    pub fn into_cstring(s: *const c_char) -> Result<Option<CString>, std::ffi::NulError> {
+        if s.is_null() {
+            Ok(None)
+        } else {
+            CString::new(
+                unsafe {CStr::from_ptr(s)}.to_bytes()
+            ).map(Some)
+        }
+    }
+    
+    #[cfg(test)]
+    mod tests {
+        use super::*;
+        use std::ptr;
+        
+        #[test]
+        fn test_null_cstring() {
+            assert_eq!(into_cstring(ptr::null()), Ok(None))
+        }
+        
+        #[test]
+        fn test_null_str() {
+            assert_eq!(as_str(&ptr::null()), Ok(None))
+        }
+    }
+}