Publish Comprehensive Rust 🦀

src/android/build-rules/binary.md

@@ -0,0 +1,23 @@
+# Rust Binaries
+
+Let us start with a simple application. At the root of an AOSP checkout, create
+the following files:
+
+_hello_rust/Android.bp_:
+
+```javascript
+{{#include binary/Android.bp}}
+```
+
+_hello_rust/src/main.rs_:
+
+```rust
+{{#include binary/src/main.rs:main}}
+```
+
+You can now build, push, and run the binary:
+
+```shell
+{{#include ../build_all.sh:hello_rust}}
+Hello from Rust!
+```

src/android/build-rules/binary/Android.bp

@@ -0,0 +1,5 @@
+rust_binary {
+    name: "hello_rust",
+    crate_name: "hello_rust",
+    srcs: ["src/main.rs"],
+}

src/android/build-rules/binary/src/main.rs

@@ -0,0 +1,21 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// ANCHOR: main
+//! Rust demo.
+
+/// Prints a greeting to standard output.
+fn main() {
+    println!("Hello from Rust!");
+}

src/android/build-rules/library.md

@@ -0,0 +1,37 @@
+# Rust Libraries
+
+You use `rust_library` to create a new Rust library for Android.
+
+Here we declare a dependency on two libraries:
+
+* `libgreeting`, which we define below,
+* `libtextwrap`, which is a crate already vendored in
+  [`external/rust/crates/`][crates].
+
+[crates]: https://cs.android.com/android/platform/superproject/+/master:external/rust/crates/
+
+_hello_rust/Android.bp_:
+
+```javascript
+{{#include library/Android.bp}}
+```
+
+_hello_rust/src/main.rs_:
+
+```rust,ignore
+{{#include library/src/main.rs:main}}
+```
+
+_hello_rust/src/lib.rs_:
+
+```rust,ignore
+{{#include library/src/lib.rs:greeting}}
+```
+
+You build, push, and run the binary like before:
+
+```shell
+{{#include ../build_all.sh:hello_rust_with_dep}}
+Hello Bob, it is very
+nice to meet you!
+```

src/android/build-rules/library/Android.bp

@@ -0,0 +1,16 @@
+rust_binary {
+    name: "hello_rust_with_dep",
+    crate_name: "hello_rust_with_dep",
+    srcs: ["src/main.rs"],
+    rustlibs: [
+        "libgreetings",
+        "libtextwrap",
+    ],
+    prefer_rlib: true,
+}
+
+rust_library {
+    name: "libgreetings",
+    crate_name: "greetings",
+    srcs: ["src/lib.rs"],
+}

src/android/build-rules/library/src/lib.rs

@@ -0,0 +1,21 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// ANCHOR: greeting
+//! Greeting library.
+
+/// Greet `name`.
+pub fn greeting(name: &str) -> String {
+    format!("Hello {name}, it is very nice to meet you!")
+}

src/android/build-rules/library/src/main.rs

@@ -0,0 +1,24 @@
+// Copyright 2022 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// ANCHOR: main
+//! Rust demo.
+
+use greetings::greeting;
+use textwrap::fill;
+
+/// Prints a greeting to standard output.
+fn main() {
+    println!("{}", fill(&greeting("Bob"), 24));
+}