2 files changed, 49 insertions, 0 deletions
diff --git a/crates/common/Cargo.toml b/crates/common/Cargo.toml
new file mode 100644
index 0000000..e020b17
--- /dev/null
+++ b/crates/common/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "common"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/crates/common/src/lib.rs b/crates/common/src/lib.rs
new file mode 100644
index 0000000..bb9e778
--- /dev/null
+++ b/crates/common/src/lib.rs
@@ -0,0 +1,43 @@
+use std::io;
+
+/// Resource payload that can be either borrowed from mapped bytes or owned.
+#[derive(Clone, Debug)]
+pub enum ResourceData<'a> {
+    Borrowed(&'a [u8]),
+    Owned(Vec<u8>),
+}
+
+impl<'a> ResourceData<'a> {
+    pub fn as_slice(&self) -> &[u8] {
+        match self {
+            Self::Borrowed(slice) => slice,
+            Self::Owned(buf) => buf.as_slice(),
+        }
+    }
+
+    pub fn into_owned(self) -> Vec<u8> {
+        match self {
+            Self::Borrowed(slice) => slice.to_vec(),
+            Self::Owned(buf) => buf,
+        }
+    }
+}
+
+impl AsRef<[u8]> for ResourceData<'_> {
+    fn as_ref(&self) -> &[u8] {
+        self.as_slice()
+    }
+}
+
+/// Output sink used by `read_into`/`load_into` APIs.
+pub trait OutputBuffer {
+    fn write_exact(&mut self, data: &[u8]) -> io::Result<()>;
+}
+
+impl OutputBuffer for Vec<u8> {
+    fn write_exact(&mut self, data: &[u8]) -> io::Result<()> {
+        self.clear();
+        self.extend_from_slice(data);
+        Ok(())
+    }
+}