Upgrade graalwasm-embed-c-code-guide.

Author: fniephaus

.github/workflows/graalwasm-embed-c-code-guide.yml

@@ -39,4 +39,4 @@ jobs:
           source ./emsdk/emsdk_env.sh
           cd graalwasm/graalwasm-embed-c-code-guide
           ./mvnw --no-transfer-progress package
-          ./mvnw --no-transfer-progress exec:java
+          ./mvnw --no-transfer-progress exec:exec

graalwasm/graalwasm-embed-c-code-guide/README.md

@@ -60,9 +60,8 @@ Put the following C program in _src/main/c/floyd.c_:
 ```c
 #include <stdio.h>
 
-void floyd() {
+void floyd(int rows) {
     int number = 1;
-    int rows = 10;
     for (int i = 1; i <= rows; i++) {
         for (int j = 1; j <= i; j++) {
             printf("%d ", number);
@@ -73,9 +72,10 @@ void floyd() {
 }
 
 int main() {
-    floyd();
+    floyd(10);
     return 0;
 }
+
 ```
 
 Note that `floyd` is defined as a separate function and can be exported.
@@ -154,23 +154,28 @@ import org.graalvm.polyglot.Value;
 
 public class App {
    public static void main(String[] args) throws IOException {
-      // Find the WebAssembly module resource
-      URL wasmFile = App.class.getResource("floyd.wasm");
-
-      // Setup context
-      Context.Builder contextBuilder = Context.newBuilder("wasm").option("wasm.Builtins", "wasi_snapshot_preview1");
-      Source.Builder sourceBuilder = Source.newBuilder("wasm", wasmFile).name("example");
-      Source source = sourceBuilder.build();
-      Context context = contextBuilder.build();
-
-      // Evaluate the WebAssembly module
-      context.eval(source);
-
-      // Execute the floyd function
-      context.getBindings("wasm").getMember("example").getMember("_initialize").executeVoid();
-      Value mainFunction = context.getBindings("wasm").getMember("example").getMember("floyd");
-      mainFunction.execute();
-      context.close();
+       // Find the WebAssembly module resource
+       URL wasmFile = App.class.getResource("floyd.wasm");
+       Source source = Source.newBuilder("wasm", wasmFile).name("example").build();
+
+       // Create Wasm context
+       try (Context context = Context.newBuilder("wasm").option("wasm.Builtins", "wasi_snapshot_preview1").build()) {
+           // Compile and instantiate the module
+           Value module = context.eval(source);
+           Value instance = module.newInstance();
+
+           // Get the exports member from the module instance
+           Value exports = instance.getMember("exports");
+
+           // Invoke an exported functions
+           exports.invokeMember("_initialize");
+           exports.invokeMember("floyd", 10);
+
+           // Or if you need to call a function multiple times
+           Value floyd = exports.getMember("floyd");
+           floyd.execute(4);
+           floyd.execute(8);
+       }
    }
 }
 ```
@@ -181,7 +186,7 @@ Compile and run this Java application with Maven:
 
 ```shell
 mvw package
-mvn exec:java -Dexec.mainClass=com.example.App
+mvn exec:exec
 ```
 
 The expected output should contain the first 10 lines of [Floyd's triangle](https://en.wikipedia.org/wiki/Floyd%27s_triangle), printed using the C function:

graalwasm/graalwasm-embed-c-code-guide/pom.xml

@@ -13,6 +13,8 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <maven.compiler.release>21</maven.compiler.release>
+        <truffle.jvm.arg1>--enable-native-access=ALL-UNNAMED</truffle.jvm.arg1>
+        <truffle.jvm.arg2>--sun-misc-unsafe-memory-access=allow</truffle.jvm.arg2>
     </properties>
 
     <dependencyManagement>
@@ -95,13 +97,23 @@
                     <artifactId>maven-project-info-reports-plugin</artifactId>
                     <version>3.6.1</version>
                 </plugin>
+                <plugin>
+                    <artifactId>exec-maven-plugin</artifactId>
+                    <version>1.2.1</version>
+                </plugin>
             </plugins>
         </pluginManagement>
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <configuration>
+                    <argLine>${truffle.jvm.arg1} ${truffle.jvm.arg2}</argLine>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.codehaus.mojo</groupId>
                 <artifactId>exec-maven-plugin</artifactId>
-                <version>1.2.1</version>
                 <executions>
                     <execution>
                         <id>create-output-directory</id>
@@ -129,7 +141,14 @@
                     </execution>
                 </executions>
                 <configuration>
-                    <mainClass>com.example.App</mainClass>
+                    <executable>java</executable>
+                    <arguments>
+                        <argument>-classpath</argument>
+                        <classpath/>
+                        <argument>${truffle.jvm.arg1}</argument>
+                        <argument>${truffle.jvm.arg2}</argument>
+                        <argument>com.example.App</argument>
+                    </arguments>
                 </configuration>
             </plugin>
         </plugins>

graalwasm/graalwasm-embed-c-code-guide/src/main/c/floyd.c

@@ -1,18 +1,17 @@
- #include <stdio.h>
+#include <stdio.h>
 
- void floyd() {
-     int number = 1;
-     int rows = 10;
-     for (int i = 1; i <= rows; i++) {
-         for (int j = 1; j <= i; j++) {
-             printf("%d ", number);
-             ++number;
-         }
-         printf(".\n");
-     }
- }
+void floyd(int rows) {
+    int number = 1;
+    for (int i = 1; i <= rows; i++) {
+        for (int j = 1; j <= i; j++) {
+            printf("%d ", number);
+            ++number;
+        }
+        printf(".\n");
+    }
+}
 
- int main() {
-     floyd();
-     return 0;
- }
+int main() {
+    floyd(10);
+    return 0;
+}

graalwasm/graalwasm-embed-c-code-guide/src/main/java/com/example/App.java

@@ -17,20 +17,25 @@ public class App {
     public static void main(String[] args) throws IOException {
         // Find the WebAssembly module resource
         URL wasmFile = App.class.getResource("floyd.wasm");
+        Source source = Source.newBuilder("wasm", wasmFile).name("example").build();
 
-        // Setup context
-        Context.Builder contextBuilder = Context.newBuilder("wasm").option("wasm.Builtins", "wasi_snapshot_preview1");
-        Source.Builder sourceBuilder = Source.newBuilder("wasm", wasmFile).name("example");
-        Source source = sourceBuilder.build();
-        Context context = contextBuilder.build();
+        // Create Wasm context
+        try (Context context = Context.newBuilder("wasm").option("wasm.Builtins", "wasi_snapshot_preview1").build()) {
+            // Compile and instantiate the module
+            Value module = context.eval(source);
+            Value instance = module.newInstance();
 
-        // Evaluate the WebAssembly module
-        context.eval(source);
+            // Get the exports member from the module instance
+            Value exports = instance.getMember("exports");
 
-        // Execute the floyd function
-        context.getBindings("wasm").getMember("example").getMember("_initialize").executeVoid();
-        Value mainFunction = context.getBindings("wasm").getMember("example").getMember("floyd");
-        mainFunction.execute();
-        context.close();
+            // Invoke an exported functions
+            exports.invokeMember("_initialize");
+            exports.invokeMember("floyd", 10);
+
+            // Or if you need to call a function multiple times
+            Value floyd = exports.getMember("floyd");
+            floyd.execute(4);
+            floyd.execute(8);
+        }
     }
 }