Add shared-header bindgen example

examples/bindgen/BUILD.bazel

@@ -14,11 +14,30 @@ rust_bindgen_library(
 
 rust_binary(
     name = "simple_example",
-    srcs = ["main.rs"],
+    srcs = ["simple.rs"],
     deps = [":simple_bindgen"],
 )
 
 rust_test(
     name = "simple_test",
     crate = ":simple_example",
 )
+
+rust_bindgen_library(
+    name = "hello_c_bindgen",
+    bindgen_flags = [
+        "--allowlist-function=hello",
+    ],
+    cc_lib = "//bindgen/shared:hello_c",
+    crate_name = "hello_c",
+    header = "//bindgen/shared:hello.h",
+)
+
+rust_binary(
+    name = "shared_example",
+    srcs = ["shared.rs"],
+    deps = [
+        ":hello_c_bindgen",
+        "//bindgen/shared:hello_rs",
+    ],
+)

examples/bindgen/shared.rs

@@ -0,0 +1,4 @@
+fn main() {
+    hello_rs::hello();
+    unsafe { hello_c::hello() };
+}

examples/bindgen/shared/BUILD.bazel

@@ -0,0 +1,36 @@
+load("@rules_cc//cc:defs.bzl", "cc_library")
+load("@rules_rust//bindgen:defs.bzl", "rust_bindgen")
+load("@rules_rust//rust:defs.bzl", "rust_library")
+
+package(default_visibility = ["//bindgen:__pkg__"])
+
+cc_library(
+    name = "greeting",
+    hdrs = ["greeting.h"],
+)
+
+rust_bindgen(
+    name = "greeting_bindgen",
+    bindgen_flags = [
+        "--allowlist-var=GREETING",
+        "--generate-cstr",
+    ],
+    cc_lib = ":greeting",
+    header = "greeting.h",
+)
+
+rust_library(
+    name = "hello_rs",
+    srcs = [
+        "hello.rs",
+        ":greeting_bindgen",
+    ],
+    crate_root = "hello.rs",
+)
+
+cc_library(
+    name = "hello_c",
+    srcs = ["hello.c"],
+    hdrs = ["hello.h"],
+    deps = [":greeting"],
+)

examples/bindgen/shared/greeting.h

@@ -0,0 +1,6 @@
+#ifndef __FFI_H_INCLUDE__
+#define __FFI_H_INCLUDE__
+
+#define GREETING "Hello"
+
+#endif // __FFI_H_INCLUDE__

examples/bindgen/shared/hello.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+#include "greeting.h"
+
+void hello(void) {
+  printf("%s from C!", GREETING);
+}

examples/bindgen/shared/hello.h

@@ -0,0 +1,6 @@
+#ifndef HELLO_H_INCLUDE__
+#define HELLO_H_INCLUDE__
+
+void hello(void);
+
+#endif // HELLO_H_INCLUDE__

examples/bindgen/shared/hello.rs

@@ -0,0 +1,6 @@
+mod greeting_bindgen;
+
+pub fn hello() {
+    let greeting = greeting_bindgen::GREETING.to_str().unwrap();
+    println!("{greeting} from Rust!");
+}