blob: 347cdf73fca45d013a02c875d7580b6baf9e322c [file] [log] [blame]
// Copyright 2011 Google Inc. All Rights Reserved.
#include <signal.h>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <string>
#include "ScopedLocalRef.h"
#include "UniquePtr.h"
#include "jni.h"
#include "logging.h"
#include "toStringArray.h"
#include "object.h"
namespace art {
// Determine whether or not the specified method is public.
static bool IsMethodPublic(JNIEnv* env, jclass clazz, jmethodID method_id) {
ScopedLocalRef<jobject> reflected(env, env->ToReflectedMethod(clazz, method_id, JNI_FALSE));
if (reflected.get() == NULL) {
fprintf(stderr, "Failed to get reflected method\n");
return false;
// We now have a Method instance. We need to call its
// getModifiers() method.
ScopedLocalRef<jclass> method(env, env->FindClass("java/lang/reflect/Method"));
if (method.get() == NULL) {
fprintf(stderr, "Failed to find class Method\n");
return false;
jmethodID get_modifiers = env->GetMethodID(method.get(), "getModifiers", "()I");
if (get_modifiers == NULL) {
fprintf(stderr, "Failed to find reflect.Method.getModifiers\n");
return false;
int modifiers = env->CallIntMethod(reflected.get(), get_modifiers);
if ((modifiers & kAccPublic) == 0) {
return false;
return true;
static int InvokeMain(JNIEnv* env, int argc, char** argv) {
// We want to call main() with a String array with our arguments in
// it. Create an array and populate it. Note argv[0] is not
// included.
ScopedLocalRef<jobjectArray> args(env, toStringArray(env, argv + 1));
if (args.get() == NULL) {
// Find [class].main(String[]).
// Convert "" to "com/android/Blah".
std::string class_name(argv[0]);
std::replace(class_name.begin(), class_name.end(), '.', '/');
ScopedLocalRef<jclass> klass(env, env->FindClass(class_name.c_str()));
if (klass.get() == NULL) {
fprintf(stderr, "Unable to locate class '%s'\n", class_name.c_str());
jmethodID method = env->GetStaticMethodID(klass.get(), "main", "([Ljava/lang/String;)V");
if (method == NULL) {
fprintf(stderr, "Unable to find static main(String[]) in '%s'\n", class_name.c_str());
// Make sure the method is public. JNI doesn't prevent us from
// calling a private method, so we have to check it explicitly.
if (!IsMethodPublic(env, klass.get(), method)) {
fprintf(stderr, "Sorry, main() is not public in '%s'\n", class_name.c_str());
// Invoke main().
env->CallStaticVoidMethod(klass.get(), method, args.get());
// Check whether there was an uncaught exception. We don't log any uncaught exception here;
// detaching this thread will do that for us, but it will clear the exception (and invalidate
// our JNIEnv), so we need to check here.
return env->ExceptionCheck() ? EXIT_FAILURE : EXIT_SUCCESS;
// Parse arguments. Most of it just gets passed through to the VM.
// The JNI spec defines a handful of standard arguments.
int oatexec(int argc, char** argv) {
setvbuf(stdout, NULL, _IONBF, 0);
// Skip over argv[0].
// If we're adding any additional stuff, e.g. function hook specifiers,
// add them to the count here.
// We're over-allocating, because this includes the options to the VM
// plus the options to the program.
int option_count = argc;
UniquePtr<JavaVMOption[]> options(new JavaVMOption[option_count]());
// Copy options over. Everything up to the name of the class starts
// with a '-' (the function hook stuff is strictly internal).
// [Do we need to catch & handle "-jar" here?]
bool need_extra = false;
int curr_opt, arg_idx;
for (curr_opt = arg_idx = 0; arg_idx < argc; arg_idx++) {
if (argv[arg_idx][0] != '-' && !need_extra) {
options[curr_opt++].optionString = argv[arg_idx];
// Some options require an additional argument.
need_extra = false;
if (strcmp(argv[arg_idx], "-classpath") == 0 || strcmp(argv[arg_idx], "-cp") == 0) {
// others?
need_extra = true;
if (need_extra) {
fprintf(stderr, "VM requires value after last option flag\n");
// Make sure they provided a class name. We do this after VM init
// so that things like "-Xrunjdwp:help" have the opportunity to emit
// a usage statement.
if (arg_idx == argc) {
fprintf(stderr, "Class name required\n");
// insert additional internal options here
DCHECK_LE(curr_opt, option_count);
JavaVMInitArgs init_args;
init_args.version = JNI_VERSION_1_6;
init_args.options = options.get();
init_args.nOptions = curr_opt;
init_args.ignoreUnrecognized = JNI_FALSE;
// Start VM. The current thread becomes the main thread of the VM.
JavaVM* vm = NULL;
JNIEnv* env = NULL;
if (JNI_CreateJavaVM(&vm, &env, &init_args) != JNI_OK) {
fprintf(stderr, "VM init failed (check log file)\n");
int rc = InvokeMain(env, argc - arg_idx, &argv[arg_idx]);
if (vm->DetachCurrentThread() != JNI_OK) {
fprintf(stderr, "Warning: unable to detach main thread\n");
if (vm->DestroyJavaVM() != 0) {
fprintf(stderr, "Warning: VM did not shut down cleanly\n");
return rc;
} // namespace art
int main(int argc, char** argv) {
return art::oatexec(argc, argv);