bytes converters

Author: milyin

prebindgen-ext/src/core/type_registry.rs

@@ -155,6 +155,23 @@ pub fn primitive_builtins() -> TypeRegistry {
     });
     let string_option_input = option_input(string_input.clone());
     let string_option_output = option_output(string_output.clone());
+    let bytes_input = InputFn::new(|input: &syn::Ident| -> TokenStream {
+        quote! {
+            zenoh_flat::jni::decode_byte_array(&mut env, &#input)
+                .map_err(|err| zerror!(err))?
+        }
+    });
+    let bytes_option_input = option_input(bytes_input.clone());
+    let bytes_output = OutputFn::new(|output: Option<&syn::Ident>| -> TokenStream {
+        match output {
+            Some(output) => quote! {
+                zenoh_flat::jni::encode_byte_array(&mut env, #output)
+                    .map_err(|err| zerror!(err))?
+            },
+            None => quote! { zenoh_flat::jni::null_byte_array() },
+        }
+    });
+    let bytes_option_output = option_output(bytes_output.clone());
 
     TypeRegistry::new()
         // Strings
@@ -170,6 +187,18 @@ pub fn primitive_builtins() -> TypeRegistry {
             string_option_input,
             string_option_output,
         )
+        .type_pair(
+            "Vec<u8>",
+            "jni::objects::JByteArray",
+            bytes_input,
+            bytes_output,
+        )
+        .type_pair(
+            "Option<Vec<u8>>",
+            "jni::objects::JByteArray",
+            bytes_option_input,
+            bytes_option_output,
+        )
         // Primitives
         .type_pair(
             "bool",

prebindgen-ext/src/jni/byte_array_helpers.rs

@@ -0,0 +1,24 @@
+//! JNI byte-array conversion helpers for use in type converters and runtime code.
+
+use jni::objects::{JByteArray, JObject};
+use jni::JNIEnv;
+
+/// Converts a JNI `JByteArray` into a Rust `Vec<u8>`.
+pub fn decode_byte_array(env: &mut JNIEnv, payload: &JByteArray) -> Result<Vec<u8>, String> {
+    env.convert_byte_array(payload)
+        .map_err(|err| format!("Error while decoding JByteArray: {}", err))
+}
+
+/// Converts a Rust byte slice into a JNI `JByteArray`.
+pub fn encode_byte_array<'local>(
+    env: &mut JNIEnv<'local>,
+    bytes: &[u8],
+) -> Result<JByteArray<'local>, String> {
+    env.byte_array_from_slice(bytes)
+        .map_err(|err| format!("Error while encoding JByteArray: {}", err))
+}
+
+/// Returns a null JNI byte-array handle.
+pub fn null_byte_array() -> JByteArray<'static> {
+    JByteArray::from(JObject::null())
+}

prebindgen-ext/src/jni/mod.rs

@@ -20,6 +20,7 @@
 //!   whose inner is a JNI-object-shaped wire type.
 
 pub mod body_strategy;
+pub mod byte_array_helpers;
 pub mod inline_fn_helpers;
 pub mod jni_type;
 pub mod jni_type_helper;
@@ -28,5 +29,6 @@ pub mod string_helpers;
 pub mod struct_strategy;
 
 pub use body_strategy::JniTryClosureBody;
+pub use byte_array_helpers::{decode_byte_array, encode_byte_array, null_byte_array};
 pub use string_helpers::{decode_string, encode_string, null_string};
 pub use struct_strategy::JniDecoderStruct;

zenoh-jni/build.rs

@@ -17,14 +17,6 @@ macro_rules! decode_pure {
     };
 }
 
-macro_rules! decode_env_ref {
-    ($path:path) => {
-        InputFn::new(|input: &syn::Ident| -> TokenStream {
-            quote! { $path(&env, &#input)? }
-        })
-    };
-}
-
 macro_rules! decode_env_ref_mut {
     ($path:path) => {
         InputFn::new(|input: &syn::Ident| -> TokenStream {
@@ -33,20 +25,6 @@ macro_rules! decode_env_ref_mut {
     };
 }
 
-macro_rules! decode_option_env_ref {
-    ($path:path) => {
-        InputFn::new(|input: &syn::Ident| -> TokenStream {
-            quote! {
-                if !#input.is_null() {
-                    Some($path(&env, &#input)?)
-                } else {
-                    None
-                }
-            }
-        })
-    };
-}
-
 macro_rules! decode_option_env_ref_mut {
     ($path:path) => {
         InputFn::new(|input: &syn::Ident| -> TokenStream {
@@ -161,19 +139,7 @@ macro_rules! encode_cast {
 /// bindings — into the methods phase and the Kotlin generator.
 fn shared_bindings() -> TypeRegistry {
     primitive_builtins()
-        // Strings & byte arrays (String converters now in primitive_builtins)
-        .type_pair(
-            "Vec<u8>",
-            "jni::objects::JByteArray",
-            decode_env_ref!(crate::utils::decode_byte_array),
-            NO_OUTPUT,
-        )
-        .type_pair(
-            "Option<Vec<u8>>",
-            "jni::objects::JByteArray",
-            decode_option_env_ref!(crate::utils::decode_byte_array),
-            NO_OUTPUT,
-        )
+        // String and byte-array converters are in primitive_builtins.
         // Callbacks.
         .type_pair(
             "impl Fn(Sample) + Send + Sync + 'static",