package org.graalvm.wasm.launcher;
import org.graalvm.launcher.AbstractLanguageLauncher;
import org.graalvm.options.OptionCategory;
import org.graalvm.polyglot.Context;
import org.graalvm.polyglot.PolyglotException;
import org.graalvm.polyglot.Source;
import org.graalvm.polyglot.Value;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.Set;
public class WasmLauncher extends AbstractLanguageLauncher {
private File file = null;
private VersionAction versionAction = VersionAction.None;
private String customEntryPoint = null;
private String[] programArguments = null;
private ArrayList<String> argumentErrors = null;
private static final String USAGE = "Usage: wasm [OPTION...] [FILE] [ARG...]";
public static void main(String[] args) {
new WasmLauncher().launch(args);
}
@Override
protected List<String> preprocessArguments(List<String> arguments, Map<String, String> polyglotOptions) {
final ListIterator<String> argIterator = arguments.listIterator();
final ArrayList<String> unrecognizedArguments = new ArrayList<>();
final List<String> programArgumentsList = new ArrayList<>();
argumentErrors = new ArrayList<>();
polyglotOptions.put("wasm.Builtins", "wasi_snapshot_preview1");
while (argIterator.hasNext()) {
final String argument = argIterator.next();
if (file == null) {
if (argument.startsWith("-")) {
switch (argument) {
case "--show-version":
versionAction = VersionAction.PrintAndContinue;
break;
case "--version":
versionAction = VersionAction.PrintAndExit;
break;
default:
if (argument.startsWith("--entry-point=")) {
String[] parts = argument.split("=", 2);
if (parts[1].isEmpty()) {
argumentErrors.add("Must specify function name after --entry-point.");
} else {
customEntryPoint = parts[1];
}
} else {
unrecognizedArguments.add(argument);
}
break;
}
} else {
file = new File(argument);
programArgumentsList.add(argument);
break;
}
} else {
programArgumentsList.add(argument);
break;
}
}
while (argIterator.hasNext()) {
programArgumentsList.add(argIterator.next());
}
programArguments = programArgumentsList.toArray(new String[0]);
return unrecognizedArguments;
}
@Override
protected void validateArguments(Map<String, String> polyglotOptions) {
for (String error : argumentErrors) {
System.err.println(error);
}
if (versionAction != VersionAction.PrintAndExit) {
if (file == null) {
throw abort("The binary path is missing.\n" + USAGE);
} else if (!file.exists()) {
throw abort(String.format("WebAssembly binary '%s' does not exist.", file));
}
}
}
@Override
protected void launch(Context.Builder contextBuilder) {
System.exit(execute(contextBuilder));
}
private int execute(Context.Builder contextBuilder) {
contextBuilder.arguments(getLanguageId(), programArguments);
try (Context context = contextBuilder.build()) {
runVersionAction(versionAction, context.getEngine());
context.eval(Source.newBuilder(getLanguageId(), file).build());
Value entryPoint = detectEntryPoint(context);
if (entryPoint == null) {
throw abort("No entry-point function found, cannot start program.");
}
entryPoint.execute();
return 0;
} catch (PolyglotException e) {
if (e.isExit()) {
return e.getExitStatus();
}
throw e;
} catch (IOException e) {
throw abort(String.format("Error loading file '%s': %s", file, e.getMessage()));
}
}
private Value detectEntryPoint(Context context) {
if (customEntryPoint != null) {
return context.getBindings(getLanguageId()).getMember("main").getMember(customEntryPoint);
}
Value candidate = context.getBindings(getLanguageId()).getMember("main").getMember("_start");
if (candidate == null) {
candidate = context.getBindings(getLanguageId()).getMember("main").getMember("_main");
}
return candidate;
}
@Override
protected String getLanguageId() {
return "wasm";
}
@Override
protected void printHelp(OptionCategory maxCategory) {
System.out.println();
System.out.println("Usage: wasm [OPTION...] [FILE] [ARG...]");
System.out.println("Run WebAssembly binary files on GraalVM's wasm engine.");
}
@Override
protected void collectArguments(Set<String> options) {
}
}