我在 运行 JNI android app A/libc 时收到错误消息:致命信号 11 (SIGSEGV) 在 0xdeadd00d(代码=1),线程 17729
I receive error message when run JNI android app A/libc﹕ Fatal signal 11 (SIGSEGV) at 0xdeadd00d (code=1), thread 17729
当我在 运行 android 应用程序中使用 JNI 函数和 C++ 代码时出现错误。当它 运行 时,我收到以下消息:
Fatal signal 11 (SIGSEGV) at 0xe480001d (code=1), thread 5465
最后是我的代码:
JNIEXPORT jstring JNICALL Java_ir_bassir_ndktest4_MainActivity_getName
(JNIEnv *env, jobject obj){
jclass cls = (*env)->GetObjectClass(env, obj);
jmethodID mid = (*env)->GetStaticMethodID(env, cls, "testJava", "([Ljava/lang/String)[Ljava/lang/String");
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
jstring result = (*env)->CallStaticObjectMethod(env, cls, mid, plainText);
return (*env)->NewStringUTF(env, plainText);
}
Java 一侧:
public class MainActivity extends ActionBarActivity {
public native String getName();
public static String testJava(String txt){
Log.d("BP","call back to java method");
String result = txt + "its added in JAVA";
return result;
}
static{
System.loadLibrary("HelloJNI");
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String name = getName();
Log.d("BP",name);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
此代码的 JNI 端是 C,而不是 C++,C 对指针双关的较宽松处理是问题的一部分。您的代码在这两行中断:
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
return (*env)->NewStringUTF(env, plainText);
因为NewStringUTF
有签名
jstring NewStringUTF(JNIEnv *env, const char *bytes);
这意味着这个调用中断了:
// vvvvvvvvv--- plainText is not of the right type!
(*env)->NewStringUTF(env, plainText)
C 编译器接受它,因为 jstring
是指针类型(C++ 编译器不会),所以 plainText
将被解释为 char const *
,这会继续做傻事东西。
总之,我怀疑你是想说
return result;
...但是如果你想 return plainText
,就说
return plainText;
不需要复制。
这里有正确的代码:
JNIEXPORT jstring JNICALL Java_ir_bassir_ndktest4_MainActivity_getName (JNIEnv *env, jobject obj) {
jclass cls = (*env)->GetObjectClass(env, obj);
jmethodID mid = (*env)->GetStaticMethodID(env, cls, "testJava", "(Ljava/lang/String;)Ljava/lang/String;");
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
jstring result = (*env)->CallStaticObjectMethod(env, cls, mid, plainText);
return result;
}
当我在 运行 android 应用程序中使用 JNI 函数和 C++ 代码时出现错误。当它 运行 时,我收到以下消息:
Fatal signal 11 (SIGSEGV) at 0xe480001d (code=1), thread 5465
最后是我的代码:
JNIEXPORT jstring JNICALL Java_ir_bassir_ndktest4_MainActivity_getName
(JNIEnv *env, jobject obj){
jclass cls = (*env)->GetObjectClass(env, obj);
jmethodID mid = (*env)->GetStaticMethodID(env, cls, "testJava", "([Ljava/lang/String)[Ljava/lang/String");
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
jstring result = (*env)->CallStaticObjectMethod(env, cls, mid, plainText);
return (*env)->NewStringUTF(env, plainText);
}
Java 一侧:
public class MainActivity extends ActionBarActivity {
public native String getName();
public static String testJava(String txt){
Log.d("BP","call back to java method");
String result = txt + "its added in JAVA";
return result;
}
static{
System.loadLibrary("HelloJNI");
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String name = getName();
Log.d("BP",name);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
此代码的 JNI 端是 C,而不是 C++,C 对指针双关的较宽松处理是问题的一部分。您的代码在这两行中断:
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
return (*env)->NewStringUTF(env, plainText);
因为NewStringUTF
有签名
jstring NewStringUTF(JNIEnv *env, const char *bytes);
这意味着这个调用中断了:
// vvvvvvvvv--- plainText is not of the right type!
(*env)->NewStringUTF(env, plainText)
C 编译器接受它,因为 jstring
是指针类型(C++ 编译器不会),所以 plainText
将被解释为 char const *
,这会继续做傻事东西。
总之,我怀疑你是想说
return result;
...但是如果你想 return plainText
,就说
return plainText;
不需要复制。
这里有正确的代码:
JNIEXPORT jstring JNICALL Java_ir_bassir_ndktest4_MainActivity_getName (JNIEnv *env, jobject obj) {
jclass cls = (*env)->GetObjectClass(env, obj);
jmethodID mid = (*env)->GetStaticMethodID(env, cls, "testJava", "(Ljava/lang/String;)Ljava/lang/String;");
jstring plainText = (*env)->NewStringUTF(env, "Hello from JNI ! Compiled with ABI 2222 ");
jstring result = (*env)->CallStaticObjectMethod(env, cls, mid, plainText);
return result;
}