feat(napi): implement NapiBuffer

Author: nechaido

napi/src/lib.rs

@@ -6,8 +6,8 @@ mod value;
 
 pub use env::NapiEnv;
 pub use result::{NapiError, NapiErrorKind, NapiResult};
-pub use value::{AsNapiObject, NapiAny, NapiArray, NapiBoolean, NapiNull,
-                NapiObject, NapiString, NapiUndefined, NapiValue,
+pub use value::{AsNapiObject, NapiAny, NapiArray, NapiBoolean, NapiBuffer,
+                NapiNull, NapiObject, NapiString, NapiUndefined, NapiValue,
                 NapiValueType};
 
 pub mod sys {

napi/src/value/buffer.rs

@@ -0,0 +1,69 @@
+use std::ptr;
+use std::slice;
+
+use env::NapiEnv;
+use result::NapiResult;
+use sys;
+
+use super::{AsNapiObject, NapiValue};
+
+#[derive(Debug)]
+pub struct NapiBuffer<'env, 'buf> {
+    value: sys::napi_value,
+    data: &'buf mut [u8],
+    env: &'env NapiEnv,
+}
+
+impl<'env, 'buf> NapiBuffer<'env, 'buf> {
+    pub fn new(env: &'env NapiEnv, len: usize) -> NapiResult<Self> {
+        let mut value = ptr::null_mut();
+        let mut data = ptr::null_mut();
+
+        env.handle_status(unsafe {
+            sys::napi_create_buffer(
+                env.as_sys_env(),
+                len,
+                &mut data,
+                &mut value,
+            )
+        })?;
+
+        Ok(Self {
+            value,
+            data: unsafe { slice::from_raw_parts_mut(data as *mut u8, len) },
+            env,
+        })
+    }
+
+    pub fn len(&self) -> usize {
+        self.data.len()
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.data.is_empty()
+    }
+}
+
+impl<'env, 'buf> NapiValue<'env> for NapiBuffer<'env, 'buf> {
+    fn as_sys_value(&self) -> sys::napi_value {
+        self.value
+    }
+
+    fn env(&self) -> &'env NapiEnv {
+        self.env
+    }
+}
+
+impl<'env, 'buf> AsNapiObject<'env> for NapiBuffer<'env, 'buf> {}
+
+impl<'env, 'buf> AsRef<[u8]> for NapiBuffer<'env, 'buf> {
+    fn as_ref(&self) -> &[u8] {
+        self.data
+    }
+}
+
+impl<'env, 'buf> AsMut<[u8]> for NapiBuffer<'env, 'buf> {
+    fn as_mut(&mut self) -> &mut [u8] {
+        self.data
+    }
+}

napi/src/value/mod.rs

@@ -7,6 +7,7 @@ use sys;
 mod any;
 mod array;
 mod boolean;
+mod buffer;
 mod null;
 mod number;
 mod object;
@@ -16,6 +17,7 @@ mod undefined;
 pub use self::any::NapiAny;
 pub use self::array::NapiArray;
 pub use self::boolean::NapiBoolean;
+pub use self::buffer::NapiBuffer;
 pub use self::null::NapiNull;
 pub use self::number::NapiNumber;
 pub use self::object::NapiObject;