Merge pull request #1909 from siyopao/guestptr-conversion

wiggle: GuestPtr<[u8]> => GuestPtr<str> conversions

crates/wiggle/src/lib.rs

@@ -259,7 +259,7 @@ impl<'a, T: ?Sized + Pointee> GuestPtr<'a, T> {
     /// Creates a new `GuestPtr` from the given `mem` and `pointer` values.
     ///
     /// Note that for sized types like `u32`, `GuestPtr<T>`, etc, the `pointer`
-    /// vlue is a `u32` offset into guest memory. For slices and strings,
+    /// value is a `u32` offset into guest memory. For slices and strings,
     /// `pointer` is a `(u32, u32)` offset/length pair.
     pub fn new(mem: &'a (dyn GuestMemory + 'a), pointer: T::Pointer) -> GuestPtr<'a, T> {
         GuestPtr {
@@ -488,7 +488,7 @@ impl<'a> GuestPtr<'a, str> {
         self.pointer.0
     }
 
-    /// Returns the length, in bytes, of th estring.
+    /// Returns the length, in bytes, of the string.
     pub fn len(&self) -> u32 {
         self.pointer.1
     }
@@ -499,6 +499,12 @@ impl<'a> GuestPtr<'a, str> {
         GuestPtr::new(self.mem, self.pointer)
     }
 
+    /// Returns a pointer for the underlying slice of bytes that this
+    /// pointer points to.
+    pub fn as_byte_ptr(&self) -> GuestPtr<'a, [u8]> {
+        GuestPtr::new(self.mem, self.pointer)
+    }
+
     /// Attempts to create a [`GuestStr<'_>`] from this pointer, performing
     /// bounds checks and utf-8 checks. The resulting `GuestStr` can be used
     /// as a `&str` or `&mut str` via the `Deref` and `DerefMut` traits. The
@@ -533,6 +539,14 @@ impl<'a> GuestPtr<'a, str> {
     }
 }
 
+impl<'a> GuestPtr<'a, [u8]> {
+    /// Returns a pointer to the string represented by a `[u8]` without
+    /// validating whether each u8 is a utf-8 codepoint.
+    pub fn as_str_ptr(&self) -> GuestPtr<'a, str> {
+        GuestPtr::new(self.mem, self.pointer)
+    }
+}
+
 impl<T: ?Sized + Pointee> Clone for GuestPtr<'_, T> {
     fn clone(&self) -> Self {
         *self