Name: mf23781 Date: 02/17/98


Agent.c
-------
src/share/native/sun/tools/debug/agent.c

Jlong is not necessarily a scalar type, so the jlong conversion macros are
needed.

Problems with jlong conversions:

#if defined IBM_ALL /*ibm*/
#define TIMEOUT_INFINITY (jint_to_jlong(-1))
#else /*ibm*/
#define TIMEOUT_INFINITY -1L
#endif /*ibm*/

JNIEXPORT jlong JNICALL Java_sun_tools_agent_Agent_getStackLong
  (JNIEnv *env, jobject this, jobject thread, jint frame, jint slot)
{
    jframeID frameID = getFrameID(env,thread,frame);
    jlong value;

    if((*env)->ExceptionOccurred(env))
#if defined IBM_ALL /*ibm*/
        return jlong_zero;
#else /*ibm*/
        return (jlong)0;
#endif /*ibm*/

    checkForError(env, JVMDI_GetLocalLong(env, frameID, slot, &value) );
    return value;
}

JNIEXPORT jlong JNICALL Java_sun_tools_agent_CachedField_getFieldID
  (JNIEnv *env, jclass clazz, jclass targetClass, jstring name, jstring
signature)
{
    jfieldID id;
    char *n,*s;

    n = (char *)JNU_GetStringPlatformChars(env,name,NULL);
    if(n == NULL)
    {
        JNU_ThrowNoSuchFieldError(env,"name is null");
#if defined IBM_ALL /*ibm*/
        return jlong_zero;
#else /*ibm*/
        return 0;
#endif /*ibm*/
    }

    s = (char *)JNU_GetStringPlatformChars(env,signature,NULL);
    if(s == NULL)
    {
        JNU_ReleaseStringPlatformChars(env, name, (const char *)n);
        JNU_ThrowNoSuchFieldError(env,"signature is null");
#if defined IBM_ALL /*ibm*/
        return jlong_zero;
#else /*ibm*/
        return 0;
#endif /*ibm*/
    }

    id = (*env)->GetFieldID(env,targetClass,n,s);
    if (id == NULL) {
        (*env)->ExceptionClear(env);
        id = (*env)->GetStaticFieldID(env,targetClass,n,s);
    }

    JNU_ReleaseStringPlatformChars(env, name, (const char *)n);
    JNU_ReleaseStringPlatformChars(env, signature, (const char *)s);

    return ptr_to_jlong(id);
}

static jlong getMethodID(JNIEnv *env, jclass targetClass, jstring name,
                         jstring signature, jboolean isStatic)
{
    jmethodID id;
    char *nam, *sig;

    nam = (char *)JNU_GetStringPlatformChars(env, name, NULL);
    if(nam == NULL){
        JNU_ThrowNoSuchFieldError(env, "name is null");
#if defined IBM_ALL /*ibm*/
        return jlong_zero;
#else /*ibm*/
        return 0;
#endif /*ibm*/
    }

    sig = (char *)JNU_GetStringPlatformChars(env, signature, NULL);
    if(sig == NULL) {
        JNU_ReleaseStringPlatformChars(env, name, (const char *)nam);
        JNU_ThrowNoSuchFieldError(env, "signature is null");
#if defined IBM_ALL /*ibm*/
        return jlong_zero;
#else /*ibm*/
        return 0;
#endif /*ibm*/
    }

    if (isStatic) {
        id = (*env)->GetStaticMethodID(env, targetClass, nam, sig);
    } else {
        id = (*env)->GetMethodID(env, targetClass, nam, sig);
    }

    JNU_ReleaseStringPlatformChars(env, name, (const char *)nam);
    JNU_ReleaseStringPlatformChars(env, signature, (const char *)sig);

    return ptr_to_jlong(id);
}

See also Javasoft bug 4110529

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