Use NonNull with ParameterStatus

src/pg/protocol/parameter_status.rs

@@ -1,42 +1,52 @@
-use super::Decode;
-use bytes::Bytes;
+use super::decode::{Decode, get_str};
+use std::pin::Pin;
+use std::ptr::NonNull;
 use std::{io, str};
 
 // FIXME: Use &str functions for a custom Debug
 #[derive(Debug)]
 pub struct ParameterStatus {
-    name: Vec<u8>,
-    value: Vec<u8>,
+    #[used]
+    storage: Pin<Vec<u8>>,
+    name: NonNull<str>,
+    value: NonNull<str>,
 }
 
+// SAFE: Raw pointers point to pinned memory inside the struct
+unsafe impl Send for ParameterStatus {}
+unsafe impl Sync for ParameterStatus {}
+
 impl ParameterStatus {
     #[inline]
     pub fn name(&self) -> &str {
-        unsafe { str::from_utf8_unchecked(&self.name) }
+        // SAFE: Memory is pinned
+        unsafe { self.name.as_ref() }
     }
 
     #[inline]
     pub fn value(&self) -> &str {
-        unsafe { str::from_utf8_unchecked(&self.value) }
+        // SAFE: Memory is pinned
+        unsafe { self.value.as_ref() }
     }
 }
 
 impl Decode for ParameterStatus {
     fn decode(src: &[u8]) -> io::Result<Self> {
-        let name_end = memchr::memchr(0, &src).unwrap();
-        let value_end = memchr::memchr(0, &src[(name_end + 1)..]).unwrap();
+        let storage = Pin::new(Vec::from(src));
 
-        let name = src[..name_end].into();
-        let value = src[(name_end + 1)..(name_end + 1 + value_end)].into();
+        let name = get_str(&storage).unwrap();
+        let value = get_str(&storage[name.len() + 1..]).unwrap();
 
-        Ok(Self { name, value })
+        let name = NonNull::from(name);
+        let value = NonNull::from(value);
+
+        Ok(Self { storage, name, value })
     }
 }
 
 #[cfg(test)]
 mod tests {
     use super::{Decode, ParameterStatus};
-    use bytes::Bytes;
     use std::io;
 
     const PARAM_STATUS: &[u8] = b"session_authorization\0postgres\0";