auto import from //depot/cupcake/@135843

1 files changed, 2951 insertions, 0 deletions

diff --git a/vm/Debugger.c b/vm/Debugger.c
new file mode 100644
index 000000000..c667893c3
--- /dev/null
+++ b/vm/Debugger.c
@@ -0,0 +1,2951 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/*
+ * Link between JDWP and the VM.  The code here only runs as a result of
+ * requests from the debugger, so speed is not essential.  Maintaining
+ * isolation of the JDWP code should make it easier to maintain and reuse.
+ *
+ * Collecting all debugger-related pieces here will also allow us to #ifdef
+ * the JDWP code out of release builds.
+ */
+#include "Dalvik.h"
+
+/*
+Notes on garbage collection and object registration
+
+JDWP does not allow the debugger to assume that objects passed to it
+will not be garbage collected.  It specifies explicit commands (e.g.
+ObjectReference.DisableCollection) to allow the debugger to manage
+object lifetime.  It does, however, require that the VM not re-use an
+object ID unless an explicit "dispose" call has been made, and if the
+VM asks for a now-collected object we must return INVALID_OBJECT.
+
+JDWP also requires that, while the VM is suspended, no garbage collection
+occur.  The JDWP docs suggest that this is obvious, because no threads
+can be running.  Unfortunately it's not entirely clear how to deal
+with situations where the debugger itself allocates strings or executes
+code as part of displaying variables.  The easiest way to enforce this,
+short of disabling GC whenever the debugger is connected, is to ensure
+that the debugger thread can't cause a GC: it has to expand the heap or
+fail to allocate.  (Might want to make that "is debugger thread AND all
+other threads are suspended" to avoid unnecessary heap expansion by a
+poorly-timed JDWP request.)
+
+We use an "object registry" so that we can separate our internal
+representation from what we show the debugger.  This allows us to
+return a registry table index instead of a pointer or handle.
+
+There are various approaches we can take to achieve correct behavior:
+
+(1) Disable garbage collection entirely while the debugger is attached.
+This is very easy, but doesn't allow extended debugging sessions on
+small devices.
+
+(2) Keep a list of all object references requested by or sent to the
+debugger, and include the list in the GC root set.  This ensures that
+objects the debugger might care about don't go away.  This is straightforward,
+but it can cause us to hold on to large objects and prevent finalizers from
+being executed.
+
+(3) Keep a list of what amount to weak object references.  This way we
+don't interfere with the GC, and can support JDWP requests like
+"ObjectReference.IsCollected".
+
+The current implementation is #2.  The set should be reasonably small and
+performance isn't critical, so a simple expanding array can be used.
+
+
+Notes on threads:
+
+The VM has a Thread struct associated with every active thread.  The
+ThreadId we pass to the debugger is the ObjectId for the java/lang/Thread
+object, so to retrieve the VM's Thread struct we have to scan through the
+list looking for a match.
+
+When a thread goes away, we lock the list and free the struct.  To
+avoid having the thread list updated or Thread structs freed out from
+under us, we want to acquire and hold the thread list lock while we're
+performing operations on Threads.  Exceptions to this rule are noted in
+a couple of places.
+
+We can speed this up a bit by adding a Thread struct pointer to the
+java/lang/Thread object, and ensuring that both are discarded at the
+same time.
+*/
+
+#define THREAD_GROUP_ALL ((ObjectId) 0x12345)   // magic, internal-only value
+
+#define kSlot0Sub   1000    // Eclipse workaround
+
+/*
+ * System init.  We don't allocate the registry until first use.
+ * Make sure we do this before initializing JDWP.
+ */
+bool dvmDebuggerStartup(void)
+{
+    gDvm.dbgRegistry = dvmHashTableCreate(1000, NULL);
+    return (gDvm.dbgRegistry != NULL);
+}
+
+/*
+ * Free registry storage.
+ */
+void dvmDebuggerShutdown(void)
+{
+    dvmHashTableFree(gDvm.dbgRegistry);
+    gDvm.dbgRegistry = NULL;
+}
+
+
+/*
+ * Pass these through to the VM functions.  Allows extended checking
+ * (e.g. "errorcheck" mutexes).  If nothing else we can assert() success.
+ */
+void dvmDbgInitMutex(pthread_mutex_t* pMutex)
+{
+    dvmInitMutex(pMutex);
+}
+void dvmDbgLockMutex(pthread_mutex_t* pMutex)
+{
+    dvmLockMutex(pMutex);
+}
+void dvmDbgUnlockMutex(pthread_mutex_t* pMutex)
+{
+    dvmUnlockMutex(pMutex);
+}
+void dvmDbgInitCond(pthread_cond_t* pCond)
+{
+    pthread_cond_init(pCond, NULL);
+}
+void dvmDbgCondWait(pthread_cond_t* pCond, pthread_mutex_t* pMutex)
+{
+    int cc = pthread_cond_wait(pCond, pMutex);
+    assert(cc == 0);
+}
+void dvmDbgCondSignal(pthread_cond_t* pCond)
+{
+    int cc = pthread_cond_signal(pCond);
+    assert(cc == 0);
+}
+void dvmDbgCondBroadcast(pthread_cond_t* pCond)
+{
+    int cc = pthread_cond_broadcast(pCond);
+    assert(cc == 0);
+}
+
+
+/* keep track of type, in case we need to distinguish them someday */
+typedef enum RegistryType {
+    kObjectId = 0xc1, kRefTypeId
+} RegistryType;
+
+/*
+ * Hash function for object IDs.  Since objects are at least 8 bytes, and
+ * could someday be allocated on 16-byte boundaries, we don't want to use
+ * the low 4 bits in our hash.
+ */
+static inline u4 registryHash(u4 val)
+{
+    return val >> 4;
+}
+
+/*
+ * (This is a dvmHashTableLookup() callback.)
+ */
+static int registryCompare(const void* obj1, const void* obj2)
+{
+    return (int) obj1 - (int) obj2;
+}
+
+
+/*
+ * Determine if an id is already in the list.
+ *
+ * If the list doesn't yet exist, this creates it.
+ *
+ * Lock the registry before calling here.
+ */
+static bool lookupId(ObjectId id)
+{
+    void* found;
+
+    found = dvmHashTableLookup(gDvm.dbgRegistry, registryHash((u4) id),
+                (void*)(u4) id, registryCompare, false);
+    if (found == NULL)
+        return false;
+    assert(found == (void*)(u4) id);
+    return true;
+}
+
+/*
+ * Register an object, if it hasn't already been.
+ *
+ * This is used for both ObjectId and RefTypeId.  In theory we don't have
+ * to register RefTypeIds unless we're worried about classes unloading.
+ *
+ * Null references must be represented as zero, or the debugger will get
+ * very confused.
+ */
+static ObjectId registerObject(const Object* obj, RegistryType type, bool reg)
+{
+    ObjectId id;
+
+    if (obj == NULL)
+        return 0;
+
+    assert((u4) obj != 0xcccccccc);
+    assert((u4) obj > 0x100);
+
+    id = (ObjectId)(u4)obj | ((u8) type) << 32;
+    if (!reg)
+        return id;
+
+    dvmHashTableLock(gDvm.dbgRegistry);
+    if (!gDvm.debuggerConnected) {
+        /* debugger has detached while we were doing stuff? */
+        LOGI("ignoring registerObject request in thread=%d\n",
+            dvmThreadSelf()->threadId);
+        //dvmAbort();
+        goto bail;
+    }
+
+    (void) dvmHashTableLookup(gDvm.dbgRegistry, registryHash((u4) id),
+                (void*)(u4) id, registryCompare, true);
+
+bail:
+    dvmHashTableUnlock(gDvm.dbgRegistry);
+    return id;
+}
+
+/*
+ * (This is a HashForeachFunc callback.)
+ */
+static int markRef(void* data, void* arg)
+{
+    UNUSED_PARAMETER(arg);
+
+    //LOGI("dbg mark %p\n", data);
+    dvmMarkObjectNonNull(data);
+    return 0;
+}
+
+/* Mark all of the registered debugger references so the
+ * GC doesn't collect them.
+ */
+void dvmGcMarkDebuggerRefs()
+{
+    /* dvmDebuggerStartup() may not have been called before the first GC.
+     */
+    if (gDvm.dbgRegistry != NULL) {
+        dvmHashTableLock(gDvm.dbgRegistry);
+        dvmHashForeach(gDvm.dbgRegistry, markRef, NULL);
+        dvmHashTableUnlock(gDvm.dbgRegistry);
+    }
+}
+
+/*
+ * Verify that an object has been registered.  If it hasn't, the debugger
+ * is asking for something we didn't send it, which means something
+ * somewhere is broken.
+ *
+ * If speed is an issue we can encode the registry index in the high
+ * four bytes.  We could also just hard-wire this to "true".
+ *
+ * Note this actually takes both ObjectId and RefTypeId.
+ */
+static bool objectIsRegistered(ObjectId id, RegistryType type)
+{
+    UNUSED_PARAMETER(type);
+
+    if (id == 0)        // null reference?
+        return true;
+
+    dvmHashTableLock(gDvm.dbgRegistry);
+    bool result = lookupId(id);
+    dvmHashTableUnlock(gDvm.dbgRegistry);
+    return result;
+}
+
+/*
+ * Convert to/from a RefTypeId.
+ *
+ * These are rarely NULL, but can be (e.g. java/lang/Object's superclass).
+ */
+static RefTypeId classObjectToRefTypeId(ClassObject* clazz)
+{
+    return (RefTypeId) registerObject((Object*) clazz, kRefTypeId, true);
+}
+static RefTypeId classObjectToRefTypeIdNoReg(ClassObject* clazz)
+{
+    return (RefTypeId) registerObject((Object*) clazz, kRefTypeId, false);
+}
+static ClassObject* refTypeIdToClassObject(RefTypeId id)
+{
+    assert(objectIsRegistered(id, kRefTypeId) || !gDvm.debuggerConnected);
+    return (ClassObject*)(u4) id;
+}
+
+/*
+ * Convert to/from an ObjectId.
+ */
+static ObjectId objectToObjectId(const Object* obj)
+{
+    return registerObject(obj, kObjectId, true);
+}
+static ObjectId objectToObjectIdNoReg(const Object* obj)
+{
+    return registerObject(obj, kObjectId, false);
+}
+static Object* objectIdToObject(ObjectId id)
+{
+    assert(objectIsRegistered(id, kObjectId) || !gDvm.debuggerConnected);
+    return (Object*)(u4) id;
+}
+
+/*
+ * Convert to/from a MethodId.
+ *
+ * These IDs are only guaranteed unique within a class, so they could be
+ * an enumeration index.  For now we just use the Method*.
+ */
+static MethodId methodToMethodId(const Method* meth)
+{
+    return (MethodId)(u4) meth;
+}
+static Method* methodIdToMethod(RefTypeId refTypeId, MethodId id)
+{
+    // TODO? verify "id" is actually a method in "refTypeId"
+    return (Method*)(u4) id;
+}
+
+/*
+ * Convert to/from a FieldId.
+ *
+ * These IDs are only guaranteed unique within a class, so they could be
+ * an enumeration index.  For now we just use the Field*.
+ */
+static FieldId fieldToFieldId(const Field* field)
+{
+    return (FieldId)(u4) field;
+}
+static Field* fieldIdToField(RefTypeId refTypeId, FieldId id)
+{
+    // TODO? verify "id" is actually a field in "refTypeId"
+    return (Field*)(u4) id;
+}
+
+/*
+ * Convert to/from a FrameId.
+ *
+ * We just return a pointer to the stack frame.
+ */
+static FrameId frameToFrameId(const void* frame)
+{
+    return (FrameId)(u4) frame;
+}
+static void* frameIdToFrame(FrameId id)
+{
+    return (void*)(u4) id;
+}
+
+
+/*
+ * Get the invocation request state.
+ */
+DebugInvokeReq* dvmDbgGetInvokeReq(void)
+{
+    return &dvmThreadSelf()->invokeReq;
+}
+
+/*
+ * Enable the object registry, but don't enable debugging features yet.
+ *
+ * Only called from the JDWP handler thread.
+ */
+void dvmDbgConnected(void)
+{
+    assert(!gDvm.debuggerConnected);
+
+    LOGV("JDWP has attached\n");
+    assert(dvmHashTableNumEntries(gDvm.dbgRegistry) == 0);
+    gDvm.debuggerConnected = true;
+}
+
+/*
+ * Enable all debugging features, including scans for breakpoints.
+ *
+ * This is a no-op if we're already active.
+ *
+ * Only called from the JDWP handler thread.
+ */
+void dvmDbgActive(void)
+{
+    if (gDvm.debuggerActive)
+        return;
+
+    LOGI("Debugger is active\n");
+    dvmInitBreakpoints();
+    gDvm.debuggerActive = true;
+}
+
+/*
+ * Disable debugging features.
+ *
+ * Set "debuggerConnected" to false, which disables use of the object
+ * registry.
+ *
+ * Only called from the JDWP handler thread.
+ */
+void dvmDbgDisconnected(void)
+{
+    assert(gDvm.debuggerConnected);
+
+    gDvm.debuggerActive = false;
+
+    dvmHashTableLock(gDvm.dbgRegistry);
+    gDvm.debuggerConnected = false;
+
+    LOGI("Debugger has detached; object registry had %d entries\n",
+        dvmHashTableNumEntries(gDvm.dbgRegistry));
+    //int i;
+    //for (i = 0; i < gDvm.dbgRegistryNext; i++)
+    //    LOGVV("%4d: 0x%llx\n", i, gDvm.dbgRegistryTable[i]);
+
+    dvmHashTableClear(gDvm.dbgRegistry);
+    dvmHashTableUnlock(gDvm.dbgRegistry);
+}
+
+/*
+ * Returns "true" if a debugger is connected.
+ *
+ * Does not return "true" if it's just a DDM server.
+ */
+bool dvmDbgIsDebuggerConnected(void)
+{
+    return gDvm.debuggerActive;
+}
+
+/*
+ * Get time since last debugger activity.  Used when figuring out if the
+ * debugger has finished configuring us.
+ */
+s8 dvmDbgLastDebuggerActivity(void)
+{
+    return dvmJdwpLastDebuggerActivity(gDvm.jdwpState);
+}
+
+/*
+ * JDWP thread is running, don't allow GC.
+ */
+int dvmDbgThreadRunning(void)
+{
+    return dvmChangeStatus(NULL, THREAD_RUNNING);
+}
+
+/*
+ * JDWP thread is idle, allow GC.
+ */
+int dvmDbgThreadWaiting(void)
+{
+    return dvmChangeStatus(NULL, THREAD_VMWAIT);
+}
+
+/*
+ * Restore state returned by Running/Waiting calls.
+ */
+int dvmDbgThreadContinuing(int status)
+{
+    return dvmChangeStatus(NULL, status);
+}
+
+/*
+ * The debugger wants us to exit.
+ */
+void dvmDbgExit(int status)
+{
+    // TODO? invoke System.exit() to perform exit processing; ends up
+    // in System.exitInternal(), which can call JNI exit hook
+#ifdef WITH_PROFILER
+    LOGI("GC lifetime allocation: %d bytes\n", gDvm.allocProf.allocCount);
+    if (CALC_CACHE_STATS) {
+        dvmDumpAtomicCacheStats(gDvm.instanceofCache);
+        dvmDumpBootClassPath();
+    }
+#endif
+#ifdef PROFILE_FIELD_ACCESS
+    dvmDumpFieldAccessCounts();
+#endif
+
+    exit(status);
+}
+
+
+/*
+ * ===========================================================================
+ *      Class, Object, Array
+ * ===========================================================================
+ */
+
+/*
+ * Get the class's type descriptor from a reference type ID.
+ */
+const char* dvmDbgGetClassDescriptor(RefTypeId id)
+{
+    ClassObject* clazz;
+
+    clazz = refTypeIdToClassObject(id);
+    return clazz->descriptor;
+}
+
+/*
+ * Return the superclass of a class (will be NULL for java/lang/Object).
+ */
+RefTypeId dvmDbgGetSuperclass(RefTypeId id)
+{
+    ClassObject* clazz = refTypeIdToClassObject(id);
+    return classObjectToRefTypeId(clazz->super);
+}
+
+/*
+ * Return a class's defining class loader.
+ */
+RefTypeId dvmDbgGetClassLoader(RefTypeId id)
+{
+    ClassObject* clazz = refTypeIdToClassObject(id);
+    return objectToObjectId(clazz->classLoader);
+}
+
+/*
+ * Return a class's access flags.
+ */
+u4 dvmDbgGetAccessFlags(RefTypeId id)
+{
+    ClassObject* clazz = refTypeIdToClassObject(id);
+    return clazz->accessFlags & JAVA_FLAGS_MASK;
+}
+
+/*
+ * Is this class an interface?
+ */
+bool dvmDbgIsInterface(RefTypeId id)
+{
+    ClassObject* clazz = refTypeIdToClassObject(id);
+    return dvmIsInterfaceClass(clazz);
+}
+
+/*
+ * dvmHashForeach callback
+ */
+static int copyRefType(void* vclazz, void* varg)
+{
+    RefTypeId** pRefType = (RefTypeId**)varg;
+    **pRefType = classObjectToRefTypeId((ClassObject*) vclazz);
+    (*pRefType)++;
+    return 0;
+}
+
+/*
+ * Get the complete list of reference classes (i.e. all classes except
+ * the primitive types).
+ *
+ * Returns a newly-allocated buffer full of RefTypeId values.
+ */
+void dvmDbgGetClassList(u4* pNumClasses, RefTypeId** pClassRefBuf)
+{
+    RefTypeId* pRefType;
+
+    dvmHashTableLock(gDvm.loadedClasses);
+    *pNumClasses = dvmHashTableNumEntries(gDvm.loadedClasses);
+    pRefType = *pClassRefBuf = malloc(sizeof(RefTypeId) * *pNumClasses);
+
+    if (dvmHashForeach(gDvm.loadedClasses, copyRefType, &pRefType) != 0) {
+        LOGW("Warning: problem getting class list\n");
+        /* not really expecting this to happen */
+    } else {
+        assert(pRefType - *pClassRefBuf == (int) *pNumClasses);
+    }
+
+    dvmHashTableUnlock(gDvm.loadedClasses);
+}
+
+/*
+ * Get the list of reference classes "visible" to the specified class
+ * loader.  A class is visible to a class loader if the ClassLoader object
+ * is the defining loader or is listed as an initiating loader.
+ *
+ * Returns a newly-allocated buffer full of RefTypeId values.
+ */
+void dvmDbgGetVisibleClassList(ObjectId classLoaderId, u4* pNumClasses,
+    RefTypeId** pClassRefBuf)
+{
+    Object* classLoader;
+    int numClasses = 0, maxClasses;
+
+    classLoader = objectIdToObject(classLoaderId);
+    // I don't think classLoader can be NULL, but the spec doesn't say
+
+    LOGVV("GetVisibleList: comparing to %p\n", classLoader);
+
+    dvmHashTableLock(gDvm.loadedClasses);
+
+    /* over-allocate the return buffer */
+    maxClasses = dvmHashTableNumEntries(gDvm.loadedClasses);
+    *pClassRefBuf = malloc(sizeof(RefTypeId) * maxClasses);
+
+    /*
+     * Run through the list, looking for matches.
+     */
+    HashIter iter;
+    for (dvmHashIterBegin(gDvm.loadedClasses, &iter); !dvmHashIterDone(&iter);
+        dvmHashIterNext(&iter))
+    {
+        ClassObject* clazz = (ClassObject*) dvmHashIterData(&iter);
+
+        if (clazz->classLoader == classLoader ||
+            dvmLoaderInInitiatingList(clazz, classLoader))
+        {
+            LOGVV("  match '%s'\n", clazz->descriptor);
+            (*pClassRefBuf)[numClasses++] = classObjectToRefTypeId(clazz);
+        }
+    }
+    *pNumClasses = numClasses;
+
+    dvmHashTableUnlock(gDvm.loadedClasses);
+}
+
+/*
+ * Generate the "JNI signature" for a class, e.g. "Ljava/lang/String;".
+ *
+ * Our class descriptors are in the correct format, so we just copy that.
+ * TODO: figure out if we can avoid the copy now that we're using
+ * descriptors instead of unadorned class names.
+ *
+ * Returns a newly-allocated string.
+ */
+static char* generateJNISignature(ClassObject* clazz)
+{
+    return strdup(clazz->descriptor);
+}
+
+/*
+ * Get information about a class.
+ *
+ * If "pSignature" is not NULL, *pSignature gets the "JNI signature" of
+ * the class.
+ */
+void dvmDbgGetClassInfo(RefTypeId classId, u1* pTypeTag, u4* pStatus,
+    char** pSignature)
+{
+    ClassObject* clazz = refTypeIdToClassObject(classId);
+
+    if (clazz->descriptor[0] == '[') {
+        /* generated array class */
+        *pStatus = CS_VERIFIED | CS_PREPARED;
+        *pTypeTag = TT_ARRAY;
+    } else {
+        if (clazz->status == CLASS_ERROR)
+            *pStatus = CS_ERROR;
+        else
+            *pStatus = CS_VERIFIED | CS_PREPARED | CS_INITIALIZED;
+        if (dvmIsInterfaceClass(clazz))
+            *pTypeTag = TT_INTERFACE;
+        else
+            *pTypeTag = TT_CLASS;
+    }
+    if (pSignature != NULL)
+        *pSignature = generateJNISignature(clazz);
+}
+
+/*
+ * Search the list of loaded classes for a match.
+ */
+bool dvmDbgFindLoadedClassBySignature(const char* classDescriptor,
+        RefTypeId* pRefTypeId)
+{
+    ClassObject* clazz;
+
+    clazz = dvmFindLoadedClass(classDescriptor);
+    if (clazz != NULL) {
+        *pRefTypeId = classObjectToRefTypeId(clazz);
+        return true;
+    } else
+        return false;
+}
+
+
+/*
+ * Get an object's class and "type tag".
+ */
+void dvmDbgGetObjectType(ObjectId objectId, u1* pRefTypeTag,
+    RefTypeId* pRefTypeId)
+{
+    Object* obj = objectIdToObject(objectId);
+
+    if (dvmIsArrayClass(obj->clazz))
+        *pRefTypeTag = TT_ARRAY;
+    else if (dvmIsInterfaceClass(obj->clazz))
+        *pRefTypeTag = TT_INTERFACE;
+    else
+        *pRefTypeTag = TT_CLASS;
+    *pRefTypeId = classObjectToRefTypeId(obj->clazz);
+}
+
+/*
+ * Get a class object's "type tag".
+ */
+u1 dvmDbgGetClassObjectType(RefTypeId refTypeId)
+{
+    ClassObject* clazz = refTypeIdToClassObject(refTypeId);
+
+    if (dvmIsArrayClass(clazz))
+        return TT_ARRAY;
+    else if (dvmIsInterfaceClass(clazz))
+        return TT_INTERFACE;
+    else
+        return TT_CLASS;
+}
+
+/*
+ * Get a class' signature.
+ *
+ * Returns a newly-allocated string.
+ */
+char* dvmDbgGetSignature(RefTypeId refTypeId)
+{
+    ClassObject* clazz;
+
+    clazz = refTypeIdToClassObject(refTypeId);
+    assert(clazz != NULL);
+
+    return generateJNISignature(clazz);
+}
+
+/*
+ * Get class' source file.
+ *
+ * Returns a newly-allocated string.
+ */
+const char* dvmDbgGetSourceFile(RefTypeId refTypeId)
+{
+    ClassObject* clazz;
+
+    clazz = refTypeIdToClassObject(refTypeId);
+    assert(clazz != NULL);
+
+    return clazz->sourceFile;
+}
+
+/*
+ * Get an object's type name.  Converted to a "JNI signature".
+ *
+ * Returns a newly-allocated string.
+ */
+char* dvmDbgGetObjectTypeName(ObjectId objectId)
+{
+    Object* obj = objectIdToObject(objectId);
+
+    assert(obj != NULL);
+
+    return generateJNISignature(obj->clazz);
+}
+
+/*
+ * Given a type signature (e.g. "Ljava/lang/String;"), return the JDWP
+ * "type tag".
+ *
+ * In many cases this is necessary but not sufficient.  For example, if
+ * we have a NULL String object, we want to return JT_STRING.  If we have
+ * a java/lang/Object that holds a String reference, we also want to
+ * return JT_STRING.  See dvmDbgGetObjectTag().
+ */
+int dvmDbgGetSignatureTag(const char* type)
+{
+    /*
+     * We're not checking the class loader here (to guarantee that JT_STRING
+     * is truly the one and only String), but it probably doesn't matter
+     * for our purposes.
+     */
+    if (strcmp(type, "Ljava/lang/String;") == 0)
+        return JT_STRING;
+    else if (strcmp(type, "Ljava/lang/Class;") == 0)
+        return JT_CLASS_OBJECT; 
+    else if (strcmp(type, "Ljava/lang/Thread;") == 0)
+        return JT_THREAD;
+    else if (strcmp(type, "Ljava/lang/ThreadGroup;") == 0)
+        return JT_THREAD_GROUP;
+    else if (strcmp(type, "Ljava/lang/ClassLoader;") == 0)
+        return JT_CLASS_LOADER;
+
+    switch (type[0]) {
+    case '[':       return JT_ARRAY;
+    case 'B':       return JT_BYTE;
+    case 'C':       return JT_CHAR;
+    case 'L':       return JT_OBJECT;
+    case 'F':       return JT_FLOAT;
+    case 'D':       return JT_DOUBLE;
+    case 'I':       return JT_INT;
+    case 'J':       return JT_LONG;
+    case 'S':       return JT_SHORT;
+    case 'V':       return JT_VOID;
+    case 'Z':       return JT_BOOLEAN;
+    default:
+        LOGE("ERROR: unhandled type '%s'\n", type);
+        assert(false);
+        return -1;
+    }
+}
+
+/*
+ * Methods declared to return Object might actually be returning one
+ * of the "refined types".  We need to check the object explicitly.
+ */
+static u1 resultTagFromObject(Object* obj)
+{
+    ClassObject* clazz;
+
+    if (obj == NULL)
+        return JT_OBJECT;
+
+    clazz = obj->clazz;
+
+    /*
+     * Comparing against the known classes is faster than string
+     * comparisons.  It ensures that we only find the classes in the
+     * bootstrap class loader, which may or may not be what we want.
+     */
+    if (clazz == gDvm.classJavaLangString)
+        return JT_STRING;
+    else if (clazz == gDvm.classJavaLangClass)
+        return JT_CLASS_OBJECT;
+    else if (clazz == gDvm.classJavaLangThread)
+        return JT_THREAD;
+    else if (clazz == gDvm.classJavaLangThreadGroup)
+        return JT_THREAD_GROUP;
+    else if (strcmp(clazz->descriptor, "Ljava/lang/ClassLoader;") == 0)
+        return JT_CLASS_LOADER;
+    else if (clazz->descriptor[0] == '[')
+        return JT_ARRAY;
+    else
+        return JT_OBJECT;
+}
+
+/*
+ * Determine the tag for an object with a known type.
+ */
+int dvmDbgGetObjectTag(ObjectId objectId, const char* type)
+{
+    u1 tag;
+
+    tag = dvmDbgGetSignatureTag(type);
+    if (tag == JT_OBJECT && objectId != 0)
+        tag = resultTagFromObject(objectIdToObject(objectId));
+
+    return tag;
+}
+
+/*
+ * Get the widths of the specified JDWP.Tag value.
+ */
+int dvmDbgGetTagWidth(int tag)
+{
+    switch (tag) {
+    case JT_VOID:
+        return 0;
+    case JT_BYTE:
+    case JT_BOOLEAN:
+        return 1;
+    case JT_CHAR:
+    case JT_SHORT:
+        return 2;
+    case JT_FLOAT:
+    case JT_INT:
+        return 4;
+    case JT_ARRAY:
+    case JT_OBJECT:
+    case JT_STRING:
+    case JT_THREAD:
+    case JT_THREAD_GROUP:
+    case JT_CLASS_LOADER:
+    case JT_CLASS_OBJECT:
+        return sizeof(ObjectId);
+    case JT_DOUBLE:
+    case JT_LONG:
+        return 8;
+    default:
+        LOGE("ERROR: unhandled tag '%c'\n", tag);
+        assert(false);
+        return -1;
+    }
+}
+
+/*
+ * Determine whether or not a tag represents a primitive type.
+ */
+static bool isTagPrimitive(u1 tag)
+{
+    switch (tag) {
+    case JT_BYTE:
+    case JT_CHAR:
+    case JT_FLOAT:
+    case JT_DOUBLE:
+    case JT_INT:
+    case JT_LONG:
+    case JT_SHORT:
+    case JT_VOID:
+    case JT_BOOLEAN:
+        return true;
+    case JT_ARRAY:
+    case JT_OBJECT:
+    case JT_STRING:
+    case JT_CLASS_OBJECT:
+    case JT_THREAD:
+    case JT_THREAD_GROUP:
+    case JT_CLASS_LOADER:
+        return false;
+    default:
+        LOGE("ERROR: unhandled tag '%c'\n", tag);
+        assert(false);
+        return false;
+    }
+}
+
+
+/*
+ * Return the length of the specified array.
+ */
+int dvmDbgGetArrayLength(ObjectId arrayId)
+{
+    ArrayObject* arrayObj = (ArrayObject*) objectIdToObject(arrayId);
+    assert(dvmIsArray(arrayObj));
+    return arrayObj->length;
+}
+
+/*
+ * Return a tag indicating the general type of elements in the array.
+ */
+int dvmDbgGetArrayElementTag(ObjectId arrayId)
+{
+    ArrayObject* arrayObj = (ArrayObject*) objectIdToObject(arrayId);
+
+    assert(dvmIsArray(arrayObj));
+
+    return dvmDbgGetSignatureTag(arrayObj->obj.clazz->descriptor + 1);
+}
+
+/*
+ * Copy a series of values with the specified width, changing the byte
+ * ordering to big-endian.
+ */
+static void copyValuesToBE(u1* out, const u1* in, int count, int width)
+{
+    int i;
+
+    switch (width) {
+    case 1:
+        memcpy(out, in, count);
+        break;
+    case 2:
+        for (i = 0; i < count; i++)
+            *(((u2*) out)+i) = get2BE(in + i*2);
+        break;
+    case 4:
+        for (i = 0; i < count; i++)
+            *(((u4*) out)+i) = get4BE(in + i*4);
+        break;
+    case 8:
+        for (i = 0; i < count; i++)
+            *(((u8*) out)+i) = get8BE(in + i*8);
+        break;
+    default:
+        assert(false);
+    }
+}
+
+/*
+ * Copy a series of values with the specified with, changing the
+ * byte order from big-endian.
+ */
+static void copyValuesFromBE(u1* out, const u1* in, int count, int width)
+{
+    int i;
+
+    switch (width) {
+    case 1:
+        memcpy(out, in, count);
+        break;
+    case 2:
+        for (i = 0; i < count; i++)
+            set2BE(out + i*2, *((u2*)in + i));
+        break;
+    case 4:
+        for (i = 0; i < count; i++)
+            set4BE(out + i*4, *((u4*)in + i));
+        break;
+    case 8:
+        for (i = 0; i < count; i++)
+            set8BE(out + i*8, *((u8*)in + i));
+        break;
+    default:
+        assert(false);
+    }
+}
+
+/*
+ * Output a piece of an array to the reply buffer.
+ *
+ * Returns "false" if something looks fishy.
+ */
+bool dvmDbgOutputArray(ObjectId arrayId, int firstIndex, int count,
+    ExpandBuf* pReply)
+{
+    ArrayObject* arrayObj = (ArrayObject*) objectIdToObject(arrayId);
+    const u1* data = (const u1*)arrayObj->contents;
+    u1 tag;
+
+    assert(dvmIsArray(arrayObj));
+
+    if (firstIndex + count > (int)arrayObj->length) {
+        LOGW("Request for index=%d + count=%d excceds length=%d\n",
+            firstIndex, count, arrayObj->length);
+        return false;
+    }
+
+    tag = dvmDbgGetSignatureTag(arrayObj->obj.clazz->descriptor + 1);
+
+    if (isTagPrimitive(tag)) {
+        int width = dvmDbgGetTagWidth(tag);
+        u1* outBuf;
+
+        outBuf = expandBufAddSpace(pReply, count * width);
+
+        copyValuesToBE(outBuf, data + firstIndex*width, count, width);
+    } else {
+        Object** pObjects;
+        int i;
+
+        pObjects = (Object**) data;
+        pObjects += firstIndex;
+
+        LOGV("    --> copying %d object IDs\n", count);
+        //assert(tag == JT_OBJECT);     // could be object or "refined" type
+
+        for (i = 0; i < count; i++, pObjects++) {
+            u1 thisTag;
+            if (*pObjects != NULL)
+                thisTag = resultTagFromObject(*pObjects);
+            else
+                thisTag = tag;
+            expandBufAdd1(pReply, thisTag);
+            expandBufAddObjectId(pReply, objectToObjectId(*pObjects));
+        }
+    }
+
+    return true;
+}
+
+/*
+ * Set a range of elements in an array from the data in "buf".
+ */
+bool dvmDbgSetArrayElements(ObjectId arrayId, int firstIndex, int count,
+    const u1* buf)
+{
+    ArrayObject* arrayObj = (ArrayObject*) objectIdToObject(arrayId);
+    u1* data = (u1*)arrayObj->contents;
+    u1 tag;
+
+    assert(dvmIsArray(arrayObj));
+
+    if (firstIndex + count > (int)arrayObj->length) {
+        LOGW("Attempt to set index=%d + count=%d excceds length=%d\n",
+            firstIndex, count, arrayObj->length);
+        return false;
+    }
+
+    tag = dvmDbgGetSignatureTag(arrayObj->obj.clazz->descriptor + 1);
+
+    if (isTagPrimitive(tag)) {
+        int width = dvmDbgGetTagWidth(tag);
+
+        LOGV("    --> setting %d '%c' width=%d\n", count, tag, width);
+
+        copyValuesFromBE(data + firstIndex*width, buf, count, width);
+    } else {
+        Object** pObjects;
+        int i;
+
+        pObjects = (Object**) data;
+        pObjects += firstIndex;
+
+        LOGV("    --> setting %d objects", count);
+
+        /* should do array type check here */
+        for (i = 0; i < count; i++) {
+            ObjectId id = dvmReadObjectId(&buf);
+            *pObjects++ = objectIdToObject(id);
+        }
+    }
+
+    return true;
+}
+
+/*
+ * Create a new string.
+ *
+ * The only place the reference will be held in the VM is in our registry.
+ */
+ObjectId dvmDbgCreateString(const char* str)
+{
+    StringObject* strObj;
+
+    strObj = dvmCreateStringFromCstr(str, ALLOC_DEFAULT);
+    dvmReleaseTrackedAlloc((Object*) strObj, NULL);
+    return objectToObjectId((Object*) strObj);
+}
+
+/*
+ * Determine if "instClassId" is an instance of "classId".
+ */
+bool dvmDbgMatchType(RefTypeId instClassId, RefTypeId classId)
+{
+    ClassObject* instClazz = refTypeIdToClassObject(instClassId);
+    ClassObject* clazz = refTypeIdToClassObject(classId);
+
+    return dvmInstanceof(instClazz, clazz);
+}
+
+
+/*
+ * ===========================================================================
+ *      Method and Field
+ * ===========================================================================
+ */
+
+/*
+ * Get the method name from a MethodId.
+ */
+const char* dvmDbgGetMethodName(RefTypeId refTypeId, MethodId id)
+{
+    Method* meth;
+
+    meth = methodIdToMethod(refTypeId, id);
+    return meth->name;
+}
+
+/*
+ * For ReferenceType.Fields and ReferenceType.FieldsWithGeneric:
+ * output all fields declared by the class.  Inerhited fields are
+ * not included.
+ */
+void dvmDbgOutputAllFields(RefTypeId refTypeId, bool withGeneric,
+    ExpandBuf* pReply)
+{
+    static const u1 genericSignature[1] = "";
+    ClassObject* clazz;
+    Field* field;
+    u4 declared;
+    int i;
+
+    clazz = refTypeIdToClassObject(refTypeId);
+    assert(clazz != NULL);
+
+    declared = clazz->sfieldCount + clazz->ifieldCount;
+    expandBufAdd4BE(pReply, declared);
+
+    for (i = 0; i < clazz->sfieldCount; i++) {
+        field = (Field*) &clazz->sfields[i];
+
+        expandBufAddFieldId(pReply, fieldToFieldId(field));
+        expandBufAddUtf8String(pReply, (const u1*) field->name);
+        expandBufAddUtf8String(pReply, (const u1*) field->signature);
+        if (withGeneric)
+            expandBufAddUtf8String(pReply, genericSignature);
+        expandBufAdd4BE(pReply, field->accessFlags);
+    }
+    for (i = 0; i < clazz->ifieldCount; i++) {
+        field = (Field*) &clazz->ifields[i];
+
+        expandBufAddFieldId(pReply, fieldToFieldId(field));
+        expandBufAddUtf8String(pReply, (const u1*) field->name);
+        expandBufAddUtf8String(pReply, (const u1*) field->signature);
+        if (withGeneric)
+            expandBufAddUtf8String(pReply, genericSignature);
+        expandBufAdd4BE(pReply, field->accessFlags);
+    }
+}
+
+/*
+ * For ReferenceType.Methods and ReferenceType.MethodsWithGeneric:
+ * output all methods declared by the class.  Inherited methods are
+ * not included.
+ */
+void dvmDbgOutputAllMethods(RefTypeId refTypeId, bool withGeneric,
+    ExpandBuf* pReply)
+{
+    DexStringCache stringCache;
+    static const u1 genericSignature[1] = "";
+    ClassObject* clazz;
+    Method* meth;
+    u4 declared;
+    int i;
+
+    dexStringCacheInit(&stringCache);
+    
+    clazz = refTypeIdToClassObject(refTypeId);
+    assert(clazz != NULL);
+
+    declared = clazz->directMethodCount + clazz->virtualMethodCount;
+    expandBufAdd4BE(pReply, declared);
+
+    for (i = 0; i < clazz->directMethodCount; i++) {
+        meth = &clazz->directMethods[i];
+
+        expandBufAddMethodId(pReply, methodToMethodId(meth));
+        expandBufAddUtf8String(pReply, (const u1*) meth->name);
+
+        expandBufAddUtf8String(pReply,
+            (const u1*) dexProtoGetMethodDescriptor(&meth->prototype,
+                    &stringCache));
+
+        if (withGeneric)
+            expandBufAddUtf8String(pReply, genericSignature);
+        expandBufAdd4BE(pReply, meth->accessFlags);
+    }
+    for (i = 0; i < clazz->virtualMethodCount; i++) {
+        meth = &clazz->virtualMethods[i];
+
+        expandBufAddMethodId(pReply, methodToMethodId(meth));
+        expandBufAddUtf8String(pReply, (const u1*) meth->name);
+
+        expandBufAddUtf8String(pReply,
+            (const u1*) dexProtoGetMethodDescriptor(&meth->prototype,
+                    &stringCache));
+
+        if (withGeneric)
+            expandBufAddUtf8String(pReply, genericSignature);
+        expandBufAdd4BE(pReply, meth->accessFlags);
+    }
+
+    dexStringCacheRelease(&stringCache);
+}
+
+/*
+ * Output all interfaces directly implemented by the class.
+ */
+void dvmDbgOutputAllInterfaces(RefTypeId refTypeId, ExpandBuf* pReply)
+{
+    ClassObject* clazz;
+    int i, start, count;
+
+    clazz = refTypeIdToClassObject(refTypeId);
+    assert(clazz != NULL);
+
+    if (clazz->super == NULL)
+        start = 0;
+    else
+        start = clazz->super->iftableCount;
+
+    count = clazz->iftableCount - start;
+    expandBufAdd4BE(pReply, count);
+    for (i = start; i < clazz->iftableCount; i++) {
+        ClassObject* iface = clazz->iftable[i].clazz;
+        expandBufAddRefTypeId(pReply, classObjectToRefTypeId(iface));
+    }
+}
+
+typedef struct DebugCallbackContext {
+    int numItems;
+    ExpandBuf* pReply;
+    // used by locals table
+    bool withGeneric;
+} DebugCallbackContext;
+
+static int lineTablePositionsCb(void *cnxt, u4 address, u4 lineNum) 
+{
+    DebugCallbackContext *pContext = (DebugCallbackContext *)cnxt;
+
+    expandBufAdd8BE(pContext->pReply, address);
+    expandBufAdd4BE(pContext->pReply, lineNum);
+    pContext->numItems++;
+
+    return 0;
+}
+
+/*
+ * For Method.LineTable: output the line table.
+ *
+ * Note we operate in Dalvik's 16-bit units rather than bytes.
+ */
+void dvmDbgOutputLineTable(RefTypeId refTypeId, MethodId methodId,
+    ExpandBuf* pReply)
+{
+    Method* method;
+    u8 start, end;
+    int i;
+    DebugCallbackContext context;
+
+    memset (&context, 0, sizeof(DebugCallbackContext));
+
+    method = methodIdToMethod(refTypeId, methodId);
+    if (dvmIsNativeMethod(method)) {
+        start = (u8) -1;
+        end = (u8) -1;
+    } else {
+        start = 0;
+        end = dvmGetMethodInsnsSize(method);
+    }
+
+    expandBufAdd8BE(pReply, start);
+    expandBufAdd8BE(pReply, end);
+
+    // Add numLines later
+    size_t numLinesOffset = expandBufGetLength(pReply);
+    expandBufAdd4BE(pReply, 0);
+
+    context.pReply = pReply;
+
+    dexDecodeDebugInfo(method->clazz->pDvmDex->pDexFile,
+        dvmGetMethodCode(method),
+        method->clazz->descriptor,
+        method->prototype.protoIdx,
+        method->accessFlags,
+        lineTablePositionsCb, NULL, &context);
+
+    set4BE(expandBufGetBuffer(pReply) + numLinesOffset, context.numItems);
+}
+
+/*
+ * Eclipse appears to expect that the "this" reference is in slot zero.
+ * If it's not, the "variables" display will show two copies of "this",
+ * possibly because it gets "this" from SF.ThisObject and then displays
+ * all locals with nonzero slot numbers.
+ *
+ * So, we remap the item in slot 0 to 1000, and remap "this" to zero.  On
+ * SF.GetValues / SF.SetValues we map them back.
+ */
+static int tweakSlot(int slot, const char* name)
+{
+    int newSlot = slot;
+
+    if (strcmp(name, "this") == 0)      // only remap "this" ptr
+        newSlot = 0;
+    else if (slot == 0)                 // always remap slot 0
+        newSlot = kSlot0Sub;
+
+    LOGV("untweak: %d to %d\n", slot, newSlot);
+    return newSlot;
+}
+
+/*
+ * Reverse Eclipse hack.
+ */
+static int untweakSlot(int slot, const void* framePtr)
+{
+    int newSlot = slot;
+
+    if (slot == kSlot0Sub) {
+        newSlot = 0;
+    } else if (slot == 0) {
+        const StackSaveArea* saveArea = SAVEAREA_FROM_FP(framePtr);
+        const Method* method = saveArea->method;
+        newSlot = method->registersSize - method->insSize;
+    }
+
+    LOGV("untweak: %d to %d\n", slot, newSlot);
+    return newSlot;
+}
+
+static void variableTableCb (void *cnxt, u2 reg, u4 startAddress,
+        u4 endAddress, const char *name, const char *descriptor,
+        const char *signature)
+{
+    DebugCallbackContext *pContext = (DebugCallbackContext *)cnxt;
+
+    reg = (u2) tweakSlot(reg, name);
+
+    LOGV("    %2d: %d(%d) '%s' '%s' slot=%d\n",
+        pContext->numItems, startAddress, endAddress - startAddress,
+        name, descriptor, reg);
+
+    expandBufAdd8BE(pContext->pReply, startAddress);
+    expandBufAddUtf8String(pContext->pReply, (const u1*)name);
+    expandBufAddUtf8String(pContext->pReply, (const u1*)descriptor);
+    if (pContext->withGeneric) {
+        expandBufAddUtf8String(pContext->pReply, (const u1*) signature);
+    }
+    expandBufAdd4BE(pContext->pReply, endAddress - startAddress);
+    expandBufAdd4BE(pContext->pReply, reg);
+
+    pContext->numItems++;
+}
+
+/*
+ * For Method.VariableTable[WithGeneric]: output information about local
+ * variables for the specified method.
+ */
+void dvmDbgOutputVariableTable(RefTypeId refTypeId, MethodId methodId,
+    bool withGeneric, ExpandBuf* pReply)
+{
+    Method* method;
+    DebugCallbackContext context;
+
+    memset (&context, 0, sizeof(DebugCallbackContext));
+    
+    method = methodIdToMethod(refTypeId, methodId);
+
+    expandBufAdd4BE(pReply, method->insSize);
+
+    // Add numLocals later
+    size_t numLocalsOffset = expandBufGetLength(pReply);
+    expandBufAdd4BE(pReply, 0);
+
+    context.pReply = pReply;
+    context.withGeneric = withGeneric;
+    dexDecodeDebugInfo(method->clazz->pDvmDex->pDexFile,
+        dvmGetMethodCode(method),
+        method->clazz->descriptor,
+        method->prototype.protoIdx,
+        method->accessFlags,
+        NULL, variableTableCb, &context);
+
+    set4BE(expandBufGetBuffer(pReply) + numLocalsOffset, context.numItems);
+}
+
+/*
+ * Get the type tag for the field's type.
+ */
+int dvmDbgGetFieldTag(ObjectId objId, FieldId fieldId)
+{
+    Object* obj = objectIdToObject(objId);
+    RefTypeId classId = classObjectToRefTypeId(obj->clazz);
+    Field* field = fieldIdToField(classId, fieldId);
+
+    return dvmDbgGetSignatureTag(field->signature);
+}
+
+/*
+ * Get the type tag for the static field's type.
+ */
+int dvmDbgGetStaticFieldTag(RefTypeId refTypeId, FieldId fieldId)
+{
+    Field* field = fieldIdToField(refTypeId, fieldId);
+    return dvmDbgGetSignatureTag(field->signature);
+}
+
+/*
+ * Copy the value of a field into the specified buffer.
+ */
+void dvmDbgGetFieldValue(ObjectId objectId, FieldId fieldId, u1* buf,
+    int expectedLen)
+{
+    Object* obj = objectIdToObject(objectId);
+    RefTypeId classId = classObjectToRefTypeId(obj->clazz);
+    InstField* field = (InstField*) fieldIdToField(classId, fieldId);
+    Object* objVal;
+    u4 intVal;
+    u8 longVal;
+
+    switch (field->field.signature[0]) {
+    case JT_BOOLEAN:
+        assert(expectedLen == 1);
+        intVal = dvmGetFieldBoolean(obj, field->byteOffset);
+        set1(buf, intVal != 0);
+        break;
+    case JT_BYTE:
+        assert(expectedLen == 1);
+        intVal = dvmGetFieldInt(obj, field->byteOffset);
+        set1(buf, intVal);
+        break;
+    case JT_SHORT:
+    case JT_CHAR:
+        assert(expectedLen == 2);
+        intVal = dvmGetFieldInt(obj, field->byteOffset);
+        set2BE(buf, intVal);
+        break;
+    case JT_INT:
+    case JT_FLOAT:
+        assert(expectedLen == 4);
+        intVal = dvmGetFieldInt(obj, field->byteOffset);
+        set4BE(buf, intVal);
+        break;
+    case JT_ARRAY:
+    case JT_OBJECT:
+        assert(expectedLen == sizeof(ObjectId));
+        objVal = dvmGetFieldObject(obj, field->byteOffset);
+        dvmSetObjectId(buf, objectToObjectId(objVal));
+        break;
+    case JT_DOUBLE:
+    case JT_LONG:
+        assert(expectedLen == 8);
+        longVal = dvmGetFieldLong(obj, field->byteOffset);
+        set8BE(buf, longVal);
+        break;
+    default:
+        LOGE("ERROR: unhandled class type '%s'\n", field->field.signature);
+        assert(false);
+        break;
+    }
+}
+
+/*
+ * Set the value of the specified field.
+ */
+void dvmDbgSetFieldValue(ObjectId objectId, FieldId fieldId, u8 value,
+    int width)
+{
+    Object* obj = objectIdToObject(objectId);
+    RefTypeId classId = classObjectToRefTypeId(obj->clazz);
+    InstField* field = (InstField*) fieldIdToField(classId, fieldId);
+
+    switch (field->field.signature[0]) {
+    case JT_BOOLEAN:
+        assert(width == 1);
+        dvmSetFieldBoolean(obj, field->byteOffset, value != 0);
+        break;
+    case JT_BYTE:
+        assert(width == 1);
+        dvmSetFieldInt(obj, field->byteOffset, value);
+        break;
+    case JT_SHORT:
+    case JT_CHAR:
+        assert(width == 2);
+        dvmSetFieldInt(obj, field->byteOffset, value);
+        break;
+    case JT_INT:
+    case JT_FLOAT:
+        assert(width == 4);
+        dvmSetFieldInt(obj, field->byteOffset, value);
+        break;
+    case JT_ARRAY:
+    case JT_OBJECT:
+        assert(width == sizeof(ObjectId));
+        dvmSetFieldObject(obj, field->byteOffset, objectIdToObject(value));
+        break;
+    case JT_DOUBLE:
+    case JT_LONG:
+        assert(width == 8);
+        dvmSetFieldLong(obj, field->byteOffset, value);
+        break;
+    default:
+        LOGE("ERROR: unhandled class type '%s'\n", field->field.signature);
+        assert(false);
+        break;
+    }
+}
+
+/*
+ * Copy the value of a static field into the specified buffer.
+ */
+void dvmDbgGetStaticFieldValue(RefTypeId refTypeId, FieldId fieldId, u1* buf,
+    int expectedLen)
+{
+    StaticField* sfield = (StaticField*) fieldIdToField(refTypeId, fieldId);
+    Object* objVal;
+    JValue value;
+
+    switch (sfield->field.signature[0]) {
+    case JT_BOOLEAN:
+        assert(expectedLen == 1);
+        set1(buf, dvmGetStaticFieldBoolean(sfield));
+        break;
+    case JT_BYTE:
+        assert(expectedLen == 1);
+        set1(buf, dvmGetStaticFieldByte(sfield));
+        break;
+    case JT_SHORT:
+        assert(expectedLen == 2);
+        set2BE(buf, dvmGetStaticFieldShort(sfield));
+        break;
+    case JT_CHAR:
+        assert(expectedLen == 2);
+        set2BE(buf, dvmGetStaticFieldChar(sfield));
+        break;
+    case JT_INT:
+        assert(expectedLen == 4);
+        set4BE(buf, dvmGetStaticFieldInt(sfield));
+        break;
+    case JT_FLOAT:
+        assert(expectedLen == 4);
+        value.f = dvmGetStaticFieldFloat(sfield);
+        set4BE(buf, value.i);
+        break;
+    case JT_ARRAY:
+    case JT_OBJECT:
+        assert(expectedLen == sizeof(ObjectId));
+        objVal = dvmGetStaticFieldObject(sfield);
+        dvmSetObjectId(buf, objectToObjectId(objVal));
+        break;
+    case JT_LONG:
+        assert(expectedLen == 8);
+        set8BE(buf, dvmGetStaticFieldLong(sfield));
+        break;
+    case JT_DOUBLE:
+        assert(expectedLen == 8);
+        value.d = dvmGetStaticFieldDouble(sfield);
+        set8BE(buf, value.j);
+        break;
+    default:
+        LOGE("ERROR: unhandled class type '%s'\n", sfield->field.signature);
+        assert(false);
+        break;
+    }
+}
+
+/*
+ * Set the value of a static field.
+ */
+void dvmDbgSetStaticFieldValue(RefTypeId refTypeId, FieldId fieldId,
+    u8 rawValue, int width)
+{
+    StaticField* sfield = (StaticField*) fieldIdToField(refTypeId, fieldId);
+    Object* objVal;
+    JValue value;
+    
+    value.j = rawValue;
+
+    switch (sfield->field.signature[0]) {
+    case JT_BOOLEAN:
+        assert(width == 1);
+        dvmSetStaticFieldBoolean(sfield, value.z);
+        break;
+    case JT_BYTE:
+        assert(width == 1);
+        dvmSetStaticFieldByte(sfield, value.b);
+        break;
+    case JT_SHORT:
+        assert(width == 2);
+        dvmSetStaticFieldShort(sfield, value.s);
+        break;
+    case JT_CHAR:
+        assert(width == 2);
+        dvmSetStaticFieldChar(sfield, value.c);
+        break;
+    case JT_INT:
+        assert(width == 4);
+        dvmSetStaticFieldInt(sfield, value.i);
+        break;
+    case JT_FLOAT:
+        assert(width == 4);
+        dvmSetStaticFieldFloat(sfield, value.f);
+        break;
+    case JT_ARRAY:
+    case JT_OBJECT:
+        assert(width == sizeof(ObjectId));
+        objVal = objectIdToObject(rawValue);
+        dvmSetStaticFieldObject(sfield, objVal);
+        break;
+    case JT_LONG:
+        assert(width == 8);
+        dvmSetStaticFieldLong(sfield, value.j);
+        break;
+    case JT_DOUBLE:
+        assert(width == 8);
+        dvmSetStaticFieldDouble(sfield, value.d);
+        break;
+    default:
+        LOGE("ERROR: unhandled class type '%s'\n", sfield->field.signature);
+        assert(false);
+        break;
+    }
+}
+
+/*
+ * Convert a string object to a UTF-8 string.
+ *
+ * Returns a newly-allocated string.
+ */
+char* dvmDbgStringToUtf8(ObjectId strId)
+{
+    StringObject* strObj = (StringObject*) objectIdToObject(strId);
+
+    return dvmCreateCstrFromString(strObj);
+}
+
+
+/*
+ * ===========================================================================
+ *      Thread and ThreadGroup
+ * ===========================================================================
+ */
+
+/*
+ * Convert a thread object to a Thread ptr.
+ *
+ * This currently requires running through the list of threads and finding
+ * a match.
+ *
+ * IMPORTANT: grab gDvm.threadListLock before calling here.
+ */
+static Thread* threadObjToThread(Object* threadObj)
+{
+    Thread* thread;
+
+    for (thread = gDvm.threadList; thread != NULL; thread = thread->next) {
+        if (thread->threadObj == threadObj)
+            break;
+    }
+
+    return thread;
+}
+
+/*
+ * Get the status and suspend state of a thread.
+ */
+bool dvmDbgGetThreadStatus(ObjectId threadId, u4* pThreadStatus,
+    u4* pSuspendStatus)
+{
+    Object* threadObj;
+    Thread* thread;
+    bool result = false;
+    
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    /* lock the thread list, so the thread doesn't vanish while we work */
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        goto bail;
+
+    switch (thread->status) {
+    case THREAD_ZOMBIE:         *pThreadStatus = TS_ZOMBIE;     break;
+    case THREAD_RUNNING:        *pThreadStatus = TS_RUNNING;    break;
+    case THREAD_TIMED_WAIT:     *pThreadStatus = TS_SLEEPING;   break;
+    case THREAD_MONITOR:        *pThreadStatus = TS_MONITOR;    break;
+    case THREAD_WAIT:           *pThreadStatus = TS_WAIT;       break;
+    case THREAD_INITIALIZING:   *pThreadStatus = TS_ZOMBIE;     break;
+    case THREAD_STARTING:       *pThreadStatus = TS_ZOMBIE;     break;
+    case THREAD_NATIVE:         *pThreadStatus = TS_RUNNING;    break;
+    case THREAD_VMWAIT:         *pThreadStatus = TS_WAIT;       break;
+    default:
+        assert(false);
+        *pThreadStatus = THREAD_ZOMBIE;
+        break;
+    }
+
+    if (dvmIsSuspended(thread))
+        *pSuspendStatus = SUSPEND_STATUS_SUSPENDED;
+    else
+        *pSuspendStatus = 0;
+
+    result = true;
+
+bail:
+    dvmUnlockThreadList();
+    return result;
+}
+
+/*
+ * Get the thread's suspend count.
+ */
+u4 dvmDbgGetThreadSuspendCount(ObjectId threadId)
+{
+    Object* threadObj;
+    Thread* thread;
+    u4 result = 0;
+    
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    /* lock the thread list, so the thread doesn't vanish while we work */
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        goto bail;
+
+    result = thread->suspendCount;
+
+bail:
+    dvmUnlockThreadList();
+    return result;
+}
+
+/*
+ * Determine whether or not a thread exists in the VM's thread list.
+ *
+ * Returns "true" if the thread exists.
+ */
+bool dvmDbgThreadExists(ObjectId threadId)
+{
+    Object* threadObj;
+    Thread* thread;
+    bool result;
+    
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    /* lock the thread list, so the thread doesn't vanish while we work */
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        result = false;
+    else
+        result = true;
+
+    dvmUnlockThreadList();
+    return result;
+}
+
+/*
+ * Determine whether or not a thread is suspended.
+ *
+ * Returns "false" if the thread is running or doesn't exist.
+ */
+bool dvmDbgIsSuspended(ObjectId threadId)
+{
+    Object* threadObj;
+    Thread* thread;
+    bool result = false;
+    
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    /* lock the thread list, so the thread doesn't vanish while we work */
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        goto bail;
+
+    result = dvmIsSuspended(thread);
+
+bail:
+    dvmUnlockThreadList();
+    return result;
+}
+
+#if 0
+/*
+ * Wait until a thread suspends.
+ *
+ * We stray from the usual pattern here, and release the thread list lock
+ * before we use the Thread.  This is necessary and should be safe in this
+ * circumstance; see comments in dvmWaitForSuspend().
+ */
+void dvmDbgWaitForSuspend(ObjectId threadId)
+{
+    Object* threadObj;
+    Thread* thread;
+    
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    dvmLockThreadList(NULL);
+    thread = threadObjToThread(threadObj);
+    dvmUnlockThreadList();
+
+    if (thread != NULL)
+        dvmWaitForSuspend(thread);
+}
+#endif
+
+
+/*
+ * Return the ObjectId for the "system" thread group.
+ */
+ObjectId dvmDbgGetSystemThreadGroupId(void)
+{
+    Object* groupObj = dvmGetSystemThreadGroup();
+    return objectToObjectId(groupObj);
+}
+
+/*
+ * Return the ObjectId for the "system" thread group.
+ */
+ObjectId dvmDbgGetMainThreadGroupId(void)
+{
+    Object* groupObj = dvmGetMainThreadGroup();
+    return objectToObjectId(groupObj);
+}
+
+/*
+ * Get the name of a thread.
+ *
+ * Returns a newly-allocated string.
+ */
+char* dvmDbgGetThreadName(ObjectId threadId)
+{
+    Object* threadObj;
+    StringObject* nameStr;
+    char* str;
+    char* result;
+
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    nameStr = (StringObject*) dvmGetFieldObject(threadObj,
+                                                gDvm.offJavaLangThread_name);
+    str = dvmCreateCstrFromString(nameStr);
+    result = (char*) malloc(strlen(str) + 20);
+
+    /* lock the thread list, so the thread doesn't vanish while we work */
+    dvmLockThreadList(NULL);
+    Thread* thread = threadObjToThread(threadObj);
+    if (thread != NULL)
+        sprintf(result, "<%d> %s", thread->threadId, str);
+    else
+        sprintf(result, "%s", str);
+    dvmUnlockThreadList();
+
+    free(str);
+    return result;
+}
+
+/*
+ * Get a thread's group.
+ */
+ObjectId dvmDbgGetThreadGroup(ObjectId threadId)
+{
+    Object* threadObj;
+    Object* group;
+
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    group = dvmGetFieldObject(threadObj, gDvm.offJavaLangThread_group);
+    return objectToObjectId(group);
+}
+
+
+/*
+ * Get the name of a thread group.
+ *
+ * Returns a newly-allocated string.
+ */
+char* dvmDbgGetThreadGroupName(ObjectId threadGroupId)
+{
+    Object* threadGroup;
+    InstField* nameField;
+    StringObject* nameStr;
+
+    threadGroup = objectIdToObject(threadGroupId);
+    assert(threadGroup != NULL);
+
+    nameField = dvmFindInstanceField(gDvm.classJavaLangThreadGroup,
+                    "name", "Ljava/lang/String;");
+    if (nameField == NULL) {
+        LOGE("unable to find name field in ThreadGroup\n");
+        return NULL;
+    }
+
+    nameStr = (StringObject*) dvmGetFieldObject(threadGroup,
+                                                nameField->byteOffset);
+    return dvmCreateCstrFromString(nameStr);
+}
+
+/*
+ * Get the parent of a thread group.
+ *
+ * Returns a newly-allocated string.
+ */
+ObjectId dvmDbgGetThreadGroupParent(ObjectId threadGroupId)
+{
+    Object* threadGroup;
+    InstField* parentField;
+    Object* parent;
+
+    threadGroup = objectIdToObject(threadGroupId);
+    assert(threadGroup != NULL);
+
+    parentField = dvmFindInstanceField(gDvm.classJavaLangThreadGroup,
+                    "parent", "Ljava/lang/ThreadGroup;");
+    if (parentField == NULL) {
+        LOGE("unable to find parent field in ThreadGroup\n");
+        parent = NULL;
+    } else {
+        parent = dvmGetFieldObject(threadGroup, parentField->byteOffset);
+    }
+    return objectToObjectId(parent);
+}
+
+/*
+ * Get the list of threads in the thread group.
+ *
+ * We do this by running through the full list of threads and returning
+ * the ones that have the ThreadGroup object as their owner.
+ *
+ * If threadGroupId is set to "kAllThreads", we ignore the group field and
+ * return all threads.
+ *
+ * The caller must free "*ppThreadIds".
+ */
+void dvmDbgGetThreadGroupThreads(ObjectId threadGroupId,
+    ObjectId** ppThreadIds, u4* pThreadCount)
+{
+    Object* targetThreadGroup = NULL;
+    InstField* groupField = NULL;
+    Thread* thread;
+    int count;
+
+    if (threadGroupId != THREAD_GROUP_ALL) {
+        targetThreadGroup = objectIdToObject(threadGroupId);
+        assert(targetThreadGroup != NULL);
+    }
+
+    groupField = dvmFindInstanceField(gDvm.classJavaLangThread,
+        "group", "Ljava/lang/ThreadGroup;");
+
+    dvmLockThreadList(NULL);
+
+    thread = gDvm.threadList;
+    count = 0;
+    for (thread = gDvm.threadList; thread != NULL; thread = thread->next) {
+        Object* group;
+
+        /* Skip over the JDWP support thread.  Some debuggers
+         * get bent out of shape when they can't suspend and
+         * query all threads, so it's easier if we just don't
+         * tell them about us.
+         */
+        if (thread->handle == dvmJdwpGetDebugThread(gDvm.jdwpState))
+            continue;
+
+        /* This thread is currently being created, and isn't ready
+         * to be seen by the debugger yet.
+         */
+        if (thread->threadObj == NULL)
+            continue;
+
+        group = dvmGetFieldObject(thread->threadObj, groupField->byteOffset);
+        if (threadGroupId == THREAD_GROUP_ALL || group == targetThreadGroup)
+            count++;
+    }
+
+    *pThreadCount = count;
+
+    if (count == 0) {
+        *ppThreadIds = NULL;
+    } else {
+        ObjectId* ptr;
+        ptr = *ppThreadIds = (ObjectId*) malloc(sizeof(ObjectId) * count);
+
+        for (thread = gDvm.threadList; thread != NULL; thread = thread->next) {
+            Object* group;
+
+            /* Skip over the JDWP support thread.  Some debuggers
+             * get bent out of shape when they can't suspend and
+             * query all threads, so it's easier if we just don't
+             * tell them about us.
+             */
+            if (thread->handle == dvmJdwpGetDebugThread(gDvm.jdwpState))
+                continue;
+
+            /* This thread is currently being created, and isn't ready
+             * to be seen by the debugger yet.
+             */
+            if (thread->threadObj == NULL)
+                continue;
+
+            group = dvmGetFieldObject(thread->threadObj,groupField->byteOffset);
+            if (threadGroupId == THREAD_GROUP_ALL || group == targetThreadGroup)
+            {
+                *ptr++ = objectToObjectId(thread->threadObj);
+                count--;
+            }
+        }
+
+        assert(count == 0);
+    }
+
+    dvmUnlockThreadList();
+}
+
+/*
+ * Get all threads.
+ *
+ * The caller must free "*ppThreadIds".
+ */
+void dvmDbgGetAllThreads(ObjectId** ppThreadIds, u4* pThreadCount)
+{
+    dvmDbgGetThreadGroupThreads(THREAD_GROUP_ALL, ppThreadIds, pThreadCount);
+}
+
+
+/*
+ * Count up the #of frames on the thread's stack.
+ *
+ * Returns -1 on failure;
+ */
+int dvmDbgGetThreadFrameCount(ObjectId threadId)
+{
+    Object* threadObj;
+    Thread* thread;
+    void* framePtr;
+    u4 count = 0;
+
+    threadObj = objectIdToObject(threadId);
+
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        goto bail;
+
+    framePtr = thread->curFrame;
+    while (framePtr != NULL) {
+        if (!dvmIsBreakFrame(framePtr))
+            count++;
+
+        framePtr = SAVEAREA_FROM_FP(framePtr)->prevFrame;
+    }
+
+bail:
+    dvmUnlockThreadList();
+    return count;
+}
+
+/*
+ * Get info for frame N from the specified thread's stack.
+ */
+bool dvmDbgGetThreadFrame(ObjectId threadId, int num, FrameId* pFrameId,
+    JdwpLocation* pLoc)
+{
+    Object* threadObj;
+    Thread* thread;
+    void* framePtr;
+    int count;
+
+    threadObj = objectIdToObject(threadId);
+
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL)
+        goto bail;
+
+    framePtr = thread->curFrame;
+    count = 0;
+    while (framePtr != NULL) {
+        const StackSaveArea* saveArea = SAVEAREA_FROM_FP(framePtr);
+        const Method* method = saveArea->method;
+
+        if (!dvmIsBreakFrame(framePtr)) {
+            if (count == num) {
+                *pFrameId = frameToFrameId(framePtr);
+                if (dvmIsInterfaceClass(method->clazz))
+                    pLoc->typeTag = TT_INTERFACE;
+                else
+                    pLoc->typeTag = TT_CLASS;
+                pLoc->classId = classObjectToRefTypeId(method->clazz);
+                pLoc->methodId = methodToMethodId(method);
+                if (dvmIsNativeMethod(method))
+                    pLoc->idx = (u8)-1;
+                else
+                    pLoc->idx = saveArea->xtra.currentPc - method->insns;
+                dvmUnlockThreadList();
+                return true;
+            }
+
+            count++;
+        }
+
+        framePtr = saveArea->prevFrame;
+    }
+
+bail:
+    dvmUnlockThreadList();
+    return false;
+}
+
+/*
+ * Get the ThreadId for the current thread.
+ */
+ObjectId dvmDbgGetThreadSelfId(void)
+{
+    Thread* self = dvmThreadSelf();
+    return objectToObjectId(self->threadObj);
+}
+
+/*
+ * Suspend the VM.
+ */
+void dvmDbgSuspendVM(bool isEvent)
+{
+    dvmSuspendAllThreads(isEvent ? SUSPEND_FOR_DEBUG_EVENT : SUSPEND_FOR_DEBUG);
+}
+
+/*
+ * Resume the VM.
+ */
+void dvmDbgResumeVM()
+{
+    dvmResumeAllThreads(SUSPEND_FOR_DEBUG);
+}
+
+/*
+ * Suspend one thread (not ourselves).
+ */
+void dvmDbgSuspendThread(ObjectId threadId)
+{
+    Object* threadObj = objectIdToObject(threadId);
+    Thread* thread;
+
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL) {
+        /* can happen if our ThreadDeath notify crosses in the mail */
+        LOGW("WARNING: threadid=%llx obj=%p no match\n", threadId, threadObj);
+    } else {
+        dvmSuspendThread(thread);
+    }
+
+    dvmUnlockThreadList();
+}
+
+/*
+ * Resume one thread (not ourselves).
+ */
+void dvmDbgResumeThread(ObjectId threadId)
+{
+    Object* threadObj = objectIdToObject(threadId);
+    Thread* thread;
+
+    dvmLockThreadList(NULL);
+
+    thread = threadObjToThread(threadObj);
+    if (thread == NULL) {
+        LOGW("WARNING: threadid=%llx obj=%p no match\n", threadId, threadObj);
+    } else {
+        dvmResumeThread(thread);
+    }
+
+    dvmUnlockThreadList();
+}
+
+/*
+ * Suspend ourselves after sending an event to the debugger.
+ */
+void dvmDbgSuspendSelf(void)
+{
+    dvmSuspendSelf(true);
+}
+
+/*
+ * Get the "this" object for the specified frame.
+ */
+static Object* getThisObject(const u4* framePtr)
+{
+    const StackSaveArea* saveArea = SAVEAREA_FROM_FP(framePtr);
+    const Method* method = saveArea->method;
+    int argOffset = method->registersSize - method->insSize;
+    Object* thisObj;
+
+    if (method == NULL) {
+        /* this is a "break" frame? */
+        assert(false);
+        return NULL;
+    }
+
+    LOGVV("  Pulling this object for frame at %p\n", framePtr);
+    LOGVV("    Method='%s' native=%d static=%d this=%p\n",
+        method->name, dvmIsNativeMethod(method),
+        dvmIsStaticMethod(method), (Object*) framePtr[argOffset]);
+
+    /*
+     * No "this" pointer for statics.  No args on the interp stack for
+     * native methods invoked directly from the VM.
+     */
+    if (dvmIsNativeMethod(method) || dvmIsStaticMethod(method))
+        thisObj = NULL;
+    else
+        thisObj = (Object*) framePtr[argOffset];
+
+    if (thisObj != NULL && !dvmIsValidObject(thisObj)) {
+        LOGW("Debugger: invalid 'this' pointer %p in %s.%s; returning NULL\n",
+            framePtr, method->clazz->descriptor, method->name);
+        thisObj = NULL;
+    }
+
+    return thisObj;
+}
+
+/*
+ * Return the "this" object for the specified frame.  The thread must be
+ * suspended.
+ */
+bool dvmDbgGetThisObject(ObjectId threadId, FrameId frameId, ObjectId* pThisId)
+{
+    const u4* framePtr = frameIdToFrame(frameId);
+    Object* thisObj;
+
+    UNUSED_PARAMETER(threadId);
+
+    thisObj = getThisObject(framePtr);
+
+    *pThisId = objectToObjectId(thisObj);
+    return true;
+}
+
+/*
+ * Copy the value of a method argument or local variable into the
+ * specified buffer.  The value will be preceeded with the tag.
+ */
+void dvmDbgGetLocalValue(ObjectId threadId, FrameId frameId, int slot,
+    u1 tag, u1* buf, int expectedLen)
+{
+    const u4* framePtr = frameIdToFrame(frameId);
+    Object* objVal;
+    u4 intVal;
+    u8 longVal;
+
+    UNUSED_PARAMETER(threadId);
+
+    slot = untweakSlot(slot, framePtr);     // Eclipse workaround
+
+    switch (tag) {
+    case JT_BOOLEAN:
+        assert(expectedLen == 1);
+        intVal = framePtr[slot];
+        set1(buf+1, intVal != 0);
+        break;
+    case JT_BYTE:
+        assert(expectedLen == 1);
+        intVal = framePtr[slot];
+        set1(buf+1, intVal);
+        break;
+    case JT_SHORT:
+    case JT_CHAR:
+        assert(expectedLen == 2);
+        intVal = framePtr[slot];
+        set2BE(buf+1, intVal);
+        break;
+    case JT_INT:
+    case JT_FLOAT:
+        assert(expectedLen == 4);
+        intVal = framePtr[slot];
+        set4BE(buf+1, intVal);
+        break;
+    case JT_ARRAY:
+        assert(expectedLen == 8);
+        {
+            /* convert to "ObjectId" */
+            objVal = (Object*)framePtr[slot];
+            if (objVal != NULL && !dvmIsValidObject(objVal)) {
+                LOGW("JDWP: slot %d expected to hold array, %p invalid\n",
+                    slot, objVal);
+                dvmAbort();         // DEBUG: make it obvious
+                objVal = NULL;
+                tag = JT_OBJECT;    // JT_ARRAY not expected for NULL ref
+            }
+            dvmSetObjectId(buf+1, objectToObjectId(objVal));
+        }
+        break;
+    case JT_OBJECT:
+        assert(expectedLen == 8);
+        {
+            /* convert to "ObjectId" */
+            objVal = (Object*)framePtr[slot];
+            //char* name;
+
+            if (objVal != NULL) {
+                if (!dvmIsValidObject(objVal)) {
+                    LOGW("JDWP: slot %d expected to hold object, %p invalid\n",
+                        slot, objVal);
+                    dvmAbort();         // DEBUG: make it obvious
+                    objVal = NULL;
+                }
+                //name = generateJNISignature(objVal->clazz);
+                tag = resultTagFromObject(objVal);
+                //free(name);
+            } else {
+                tag = JT_OBJECT;
+            }
+            dvmSetObjectId(buf+1, objectToObjectId(objVal));
+        }
+        break;
+    case JT_DOUBLE:
+    case JT_LONG:
+        assert(expectedLen == 8);
+        longVal = *(u8*)(&framePtr[slot]);
+        set8BE(buf+1, longVal);
+        break;
+    default:
+        LOGE("ERROR: unhandled tag '%c'\n", tag);
+        assert(false);
+        break;
+    }
+
+    set1(buf, tag);
+}
+
+/*
+ * Copy a new value into an argument or local variable.
+ */
+void dvmDbgSetLocalValue(ObjectId threadId, FrameId frameId, int slot, u1 tag,
+    u8 value, int width)
+{
+    u4* framePtr = frameIdToFrame(frameId);
+
+    UNUSED_PARAMETER(threadId);
+
+    slot = untweakSlot(slot, framePtr);     // Eclipse workaround
+
+    switch (tag) {
+    case JT_BOOLEAN:
+        assert(width == 1);
+        framePtr[slot] = (u4)value;
+        break;
+    case JT_BYTE:
+        assert(width == 1);
+        framePtr[slot] = (u4)value;
+        break;
+    case JT_SHORT:
+    case JT_CHAR:
+        assert(width == 2);
+        framePtr[slot] = (u4)value;
+        break;
+    case JT_INT:
+    case JT_FLOAT:
+        assert(width == 4);
+        framePtr[slot] = (u4)value;
+        break;
+    case JT_STRING:
+        /* The debugger calls VirtualMachine.CreateString to create a new
+         * string, then uses this to set the object reference, when you
+         * edit a String object */
+    case JT_ARRAY:
+    case JT_OBJECT:
+        assert(width == sizeof(ObjectId));
+        framePtr[slot] = (u4) objectIdToObject(value);
+        break;
+    case JT_DOUBLE:
+    case JT_LONG:
+        assert(width == 8);
+        *(u8*)(&framePtr[slot]) = value;
+        break;
+    case JT_VOID:
+    case JT_CLASS_OBJECT:
+    case JT_THREAD:
+    case JT_THREAD_GROUP:
+    case JT_CLASS_LOADER:
+    default:
+        LOGE("ERROR: unhandled tag '%c'\n", tag);
+        assert(false);
+        break;
+    }
+}
+
+
+/*
+ * ===========================================================================
+ *      Debugger notification
+ * ===========================================================================
+ */
+
+/*
+ * Tell JDWP that a breakpoint address has been reached.
+ *
+ * "pcOffset" will be -1 for native methods.
+ * "thisPtr" will be NULL for static methods.
+ */
+void dvmDbgPostLocationEvent(const Method* method, int pcOffset,
+    Object* thisPtr, int eventFlags)
+{
+    JdwpLocation loc;
+
+    if (dvmIsInterfaceClass(method->clazz))
+        loc.typeTag = TT_INTERFACE;
+    else
+        loc.typeTag = TT_CLASS;
+    loc.classId = classObjectToRefTypeId(method->clazz);
+    loc.methodId = methodToMethodId(method);
+    loc.idx = pcOffset;
+
+    /*
+     * Note we use "NoReg" so we don't keep track of references that are
+     * never actually sent to the debugger.  The "thisPtr" is used to
+     * compare against registered events.
+     */
+
+    if (dvmJdwpPostLocationEvent(gDvm.jdwpState, &loc,
+            objectToObjectIdNoReg(thisPtr), eventFlags))
+    {
+        classObjectToRefTypeId(method->clazz);
+        objectToObjectId(thisPtr);
+    }
+}
+
+/*
+ * Tell JDWP that an exception has occurred.
+ */
+void dvmDbgPostException(void* throwFp, int throwRelPc, void* catchFp,
+    int catchRelPc, Object* exception)
+{
+    JdwpLocation throwLoc, catchLoc;
+    const Method* throwMeth;
+    const Method* catchMeth;
+
+    throwMeth = SAVEAREA_FROM_FP(throwFp)->method;
+    if (dvmIsInterfaceClass(throwMeth->clazz))
+        throwLoc.typeTag = TT_INTERFACE;
+    else
+        throwLoc.typeTag = TT_CLASS;
+    throwLoc.classId = classObjectToRefTypeId(throwMeth->clazz);
+    throwLoc.methodId = methodToMethodId(throwMeth);
+    throwLoc.idx = throwRelPc;
+
+    if (catchRelPc < 0) {
+        memset(&catchLoc, 0, sizeof(catchLoc));
+    } else {
+        catchMeth = SAVEAREA_FROM_FP(catchFp)->method;
+        if (dvmIsInterfaceClass(catchMeth->clazz))
+            catchLoc.typeTag = TT_INTERFACE;
+        else
+            catchLoc.typeTag = TT_CLASS;
+        catchLoc.classId = classObjectToRefTypeId(catchMeth->clazz);
+        catchLoc.methodId = methodToMethodId(catchMeth);
+        catchLoc.idx = catchRelPc;
+    }
+
+    /* need this for InstanceOnly filters */
+    Object* thisObj = getThisObject(throwFp);
+
+    dvmJdwpPostException(gDvm.jdwpState, &throwLoc, objectToObjectId(exception),
+        classObjectToRefTypeId(exception->clazz), &catchLoc,
+        objectToObjectId(thisObj));
+}
+
+/*
+ * Tell JDWP and/or DDMS that a thread has started.
+ */
+void dvmDbgPostThreadStart(Thread* thread)
+{
+    if (gDvm.debuggerActive) {
+        dvmJdwpPostThreadChange(gDvm.jdwpState,
+            objectToObjectId(thread->threadObj), true);
+    }
+    if (gDvm.ddmThreadNotification)
+        dvmDdmSendThreadNotification(thread, true);
+}
+
+/*
+ * Tell JDWP and/or DDMS that a thread has gone away.
+ */
+void dvmDbgPostThreadDeath(Thread* thread)
+{
+    if (gDvm.debuggerActive) {
+        dvmJdwpPostThreadChange(gDvm.jdwpState,
+            objectToObjectId(thread->threadObj), false);
+    }
+    if (gDvm.ddmThreadNotification)
+        dvmDdmSendThreadNotification(thread, false);
+}
+
+/*
+ * Tell JDWP that a new class has been prepared.
+ */
+void dvmDbgPostClassPrepare(ClassObject* clazz)
+{
+    int tag;
+    char* signature;
+
+    if (dvmIsInterfaceClass(clazz))
+        tag = TT_INTERFACE;
+    else
+        tag = TT_CLASS;
+
+    // TODO - we currently always send both "verified" and "prepared" since
+    // debuggers seem to like that.  There might be some advantage to honesty,
+    // since the class may not yet be verified.
+    signature = generateJNISignature(clazz);
+    dvmJdwpPostClassPrepare(gDvm.jdwpState, tag, classObjectToRefTypeId(clazz),
+        signature, CS_VERIFIED | CS_PREPARED);
+    free(signature);
+}
+
+/*
+ * The JDWP event mechanism has registered an event with a LocationOnly
+ * mod.  Tell the interpreter to call us if we hit the specified
+ * address.
+ */
+bool dvmDbgWatchLocation(const JdwpLocation* pLoc)
+{
+    Method* method = methodIdToMethod(pLoc->classId, pLoc->methodId);
+    assert(!dvmIsNativeMethod(method));
+    dvmAddBreakAddr(method, pLoc->idx);
+    return true;        /* assume success */
+}
+
+/*
+ * An event with a LocationOnly mod has been removed.
+ */
+void dvmDbgUnwatchLocation(const JdwpLocation* pLoc)
+{
+    Method* method = methodIdToMethod(pLoc->classId, pLoc->methodId);
+    assert(!dvmIsNativeMethod(method));
+    dvmClearBreakAddr(method, pLoc->idx);
+}
+
+/*
+ * The JDWP event mechanism has registered a single-step event.  Tell
+ * the interpreter about it.
+ */
+bool dvmDbgConfigureStep(ObjectId threadId, enum JdwpStepSize size,
+    enum JdwpStepDepth depth)
+{
+    Object* threadObj;
+    Thread* thread;
+    bool result = false;
+
+    threadObj = objectIdToObject(threadId);
+    assert(threadObj != NULL);
+
+    /*
+     * Get a pointer to the Thread struct for this ID.  The pointer will
+     * be used strictly for comparisons against the current thread pointer
+     * after the setup is complete, so we can safely release the lock.
+     */
+    dvmLockThreadList(NULL);
+    thread = threadObjToThread(threadObj);
+
+    if (thread == NULL) {
+        LOGE("Thread for single-step not found\n");
+        goto bail;
+    }
+    if (!dvmIsSuspended(thread)) {
+        LOGE("Thread for single-step not suspended\n");
+        assert(!"non-susp step");      // I want to know if this can happen
+        goto bail;
+    }
+
+    assert(dvmIsSuspended(thread));
+    if (!dvmAddSingleStep(thread, size, depth))
+        goto bail;
+
+    result = true;
+
+bail:
+    dvmUnlockThreadList();
+    return result;
+}
+
+/*
+ * A single-step event has been removed.
+ */
+void dvmDbgUnconfigureStep(ObjectId threadId)
+{
+    UNUSED_PARAMETER(threadId);
+
+    /* right now it's global, so don't need to find Thread */
+    dvmClearSingleStep(NULL);
+}
+
+/*
+ * Invoke a method in a thread that has been stopped on a breakpoint or
+ * other debugger event.  (This function is called from the JDWP thread.)
+ *
+ * Note that access control is not enforced, per spec.
+ */
+JdwpError dvmDbgInvokeMethod(ObjectId threadId, ObjectId objectId,
+    RefTypeId classId, MethodId methodId, u4 numArgs, ObjectId* argArray,
+    u4 options, u1* pResultTag, u8* pResultValue, ObjectId* pExceptObj)
+{
+    Object* threadObj = objectIdToObject(threadId);
+    Thread* targetThread;
+    JdwpError err = ERR_NONE;
+
+    dvmLockThreadList(NULL);
+
+    targetThread = threadObjToThread(threadObj);
+    if (targetThread == NULL) {
+        err = ERR_INVALID_THREAD;       /* thread does not exist */
+        dvmUnlockThreadList();
+        goto bail;
+    }
+    if (!targetThread->invokeReq.ready) {
+        err = ERR_INVALID_THREAD;       /* thread not stopped by event */
+        dvmUnlockThreadList();
+        goto bail;
+    }
+
+    /*
+     * TODO: ought to screen the various IDs, and verify that the argument
+     * list is valid.
+     */
+
+    targetThread->invokeReq.obj = objectIdToObject(objectId);
+    targetThread->invokeReq.thread = threadObj;
+    targetThread->invokeReq.clazz = refTypeIdToClassObject(classId);
+    targetThread->invokeReq.method = methodIdToMethod(classId, methodId);
+    targetThread->invokeReq.numArgs = numArgs;
+    targetThread->invokeReq.argArray = argArray;
+    targetThread->invokeReq.options = options;
+    targetThread->invokeReq.invokeNeeded = true;
+
+    /*
+     * This is a bit risky -- if the thread goes away we're sitting high
+     * and dry -- but we must release this before the dvmResumeAllThreads
+     * call, and it's unwise to hold it during dvmWaitForSuspend.
+     */
+    dvmUnlockThreadList();
+
+    /*
+     * We change our thread status (which should be THREAD_RUNNING) so the
+     * VM can suspend for a GC if the invoke request causes us to run out
+     * of memory.  It's also a good idea to change it before locking the
+     * invokeReq mutex, although that should never be held for long.
+     */
+    Thread* self = dvmThreadSelf();
+    int oldStatus = dvmChangeStatus(self, THREAD_VMWAIT);
+
+    LOGV("    Transferring control to event thread\n");
+    dvmLockMutex(&targetThread->invokeReq.lock);
+
+    if ((options & INVOKE_SINGLE_THREADED) == 0) {
+        LOGV("      Resuming all threads\n");
+        dvmResumeAllThreads(SUSPEND_FOR_DEBUG_EVENT);
+    } else {
+        LOGV("      Resuming event thread only\n");
+        dvmResumeThread(targetThread);
+    }
+
+    /*
+     * Wait for the request to finish executing.
+     */
+    while (targetThread->invokeReq.invokeNeeded) {
+        pthread_cond_wait(&targetThread->invokeReq.cv,
+                          &targetThread->invokeReq.lock);
+    }
+    dvmUnlockMutex(&targetThread->invokeReq.lock);
+    LOGV("    Control has returned from event thread\n");
+
+    /* wait for thread to re-suspend itself */
+    dvmWaitForSuspend(targetThread);
+
+    /*
+     * Done waiting, switch back to RUNNING.
+     */
+    dvmChangeStatus(self, oldStatus);
+
+    /*
+     * Suspend the threads.  We waited for the target thread to suspend
+     * itself, so all we need to do is suspend the others.
+     *
+     * The suspendAllThreads() call will double-suspend the event thread,
+     * so we want to resume the target thread once to keep the books straight.
+     */
+    if ((options & INVOKE_SINGLE_THREADED) == 0) {
+        LOGV("      Suspending all threads\n");
+        dvmSuspendAllThreads(SUSPEND_FOR_DEBUG_EVENT);
+        LOGV("      Resuming event thread to balance the count\n");
+        dvmResumeThread(targetThread);
+    }
+
+    /*
+     * Set up the result.
+     */
+    *pResultTag = targetThread->invokeReq.resultTag;
+    if (isTagPrimitive(targetThread->invokeReq.resultTag))
+        *pResultValue = targetThread->invokeReq.resultValue.j;
+    else
+        *pResultValue = objectToObjectId(targetThread->invokeReq.resultValue.l);
+    *pExceptObj = targetThread->invokeReq.exceptObj;
+    err = targetThread->invokeReq.err;
+
+bail:
+    return err;
+}
+
+/*
+ * Determine the tag type for the return value for this method.
+ */
+static u1 resultTagFromSignature(const Method* method)
+{
+    const char* descriptor = dexProtoGetReturnType(&method->prototype);
+    return dvmDbgGetSignatureTag(descriptor);
+}
+
+/*
+ * Execute the method described by "*pReq".
+ */
+void dvmDbgExecuteMethod(DebugInvokeReq* pReq)
+{
+    Thread* self = dvmThreadSelf();
+    const Method* meth;
+    Object* oldExcept;
+
+    /*
+     * We can be called while an exception is pending in the VM.  We need
+     * to preserve that across the method invocation.
+     */
+    oldExcept = dvmGetException(self);
+
+    /*
+     * Translate the method through the vtable, unless we're calling a
+     * static method or the debugger wants to suppress it.
+     */
+    if ((pReq->options & INVOKE_NONVIRTUAL) != 0 || pReq->obj == NULL) {
+        meth = pReq->method;
+    } else {
+        meth = dvmGetVirtualizedMethod(pReq->clazz, pReq->method);
+    }
+    assert(meth != NULL);
+
+    assert(sizeof(jvalue) == sizeof(u8));
+
+    IF_LOGV() {
+        char* desc = dexProtoCopyMethodDescriptor(&meth->prototype);
+        LOGV("JDWP invoking method %s.%s %s\n",
+            meth->clazz->descriptor, meth->name, desc);
+        free(desc);
+    }
+
+    dvmCallMethodA(self, meth, pReq->obj, &pReq->resultValue,
+        (jvalue*)pReq->argArray);
+    pReq->exceptObj = objectToObjectId(dvmGetException(self));
+    pReq->resultTag = resultTagFromSignature(meth);
+    if (pReq->exceptObj != 0) {
+        LOGD("  JDWP invocation returning with exceptObj=%p\n",
+            dvmGetException(self));
+        dvmClearException(self);
+        /*
+         * Nothing should try to use this, but it looks like something is.
+         * Make it null to be safe.
+         */
+        pReq->resultValue.j = 0; /*0xadadadad;*/
+    } else if (pReq->resultTag == JT_OBJECT) {
+        /* if no exception thrown, examine object result more closely */
+        u1 newTag = resultTagFromObject(pReq->resultValue.l);
+        if (newTag != pReq->resultTag) {
+            LOGVV("  JDWP promoted result from %d to %d\n",
+                pReq->resultTag, newTag);
+            pReq->resultTag = newTag;
+        }
+    }
+
+    if (oldExcept != NULL)
+        dvmSetException(self, oldExcept);
+}
+
+// for dvmAddressSetForLine
+typedef struct AddressSetContext {
+    bool lastAddressValid;
+    u4 lastAddress;
+    u4 lineNum;
+    AddressSet *pSet;
+} AddressSetContext;
+
+// for dvmAddressSetForLine
+static int addressSetCb (void *cnxt, u4 address, u4 lineNum)
+{
+    AddressSetContext *pContext = (AddressSetContext *)cnxt;
+
+    if (lineNum == pContext->lineNum) {
+        if (!pContext->lastAddressValid) {
+            // Everything from this address until the next line change is ours
+            pContext->lastAddress = address;
+            pContext->lastAddressValid = true;
+        }
+        // else, If we're already in a valid range for this lineNum,
+        // just keep going (shouldn't really happen)
+    } else if (pContext->lastAddressValid) { // and the line number is new
+        u4 i;
+        // Add everything from the last entry up until here to the set
+        for (i = pContext->lastAddress; i < address; i++) {
+            dvmAddressSetSet(pContext->pSet, i);
+        }
+
+        pContext->lastAddressValid = false;
+    }
+
+    // there may be multiple entries for a line
+    return 0;
+}
+/*
+ * Build up a set of bytecode addresses associated with a line number
+ */
+const AddressSet *dvmAddressSetForLine(const Method* method, int line)
+{
+    AddressSet *result;
+    const DexFile *pDexFile = method->clazz->pDvmDex->pDexFile;
+    u4 insnsSize = dvmGetMethodInsnsSize(method);
+    AddressSetContext context;
+
+    result = calloc(1, sizeof(AddressSet) + (insnsSize/8) + 1);
+    result->setSize = insnsSize;
+
+    memset(&context, 0, sizeof(context));
+    context.pSet = result;
+    context.lineNum = line;
+    context.lastAddressValid = false;
+
+    dexDecodeDebugInfo(pDexFile, dvmGetMethodCode(method),
+        method->clazz->descriptor,
+        method->prototype.protoIdx,
+        method->accessFlags,
+        addressSetCb, NULL, &context);
+
+    // If the line number was the last in the position table...
+    if (context.lastAddressValid) {
+        u4 i;
+        for (i = context.lastAddress; i < insnsSize; i++) {
+            dvmAddressSetSet(result, i);
+        }
+    }
+
+    return result;
+}
+
+
+/*
+ * ===========================================================================
+ *      Dalvik Debug Monitor support
+ * ===========================================================================
+ */
+
+/*
+ * We have received a DDM packet over JDWP.  Hand it off to the VM.
+ */
+bool dvmDbgDdmHandlePacket(const u1* buf, int dataLen, u1** pReplyBuf,
+    int* pReplyLen)
+{
+    return dvmDdmHandlePacket(buf, dataLen, pReplyBuf, pReplyLen);
+}
+
+/*
+ * First DDM packet has arrived over JDWP.  Notify the press.
+ */
+void dvmDbgDdmConnected(void)
+{
+    dvmDdmConnected();
+}
+
+/*
+ * JDWP connection has dropped.
+ */
+void dvmDbgDdmDisconnected(void)
+{
+    dvmDdmDisconnected();
+}
+
+/*
+ * Send up a JDWP event packet with a DDM chunk in it.
+ */
+void dvmDbgDdmSendChunk(int type, int len, const u1* buf)
+{
+    if (gDvm.jdwpState == NULL) {
+        LOGI("Debugger thread not active, ignoring DDM send (t=0x%08x l=%d)\n",
+            type, len);
+        return;
+    }
+
+    dvmJdwpDdmSendChunk(gDvm.jdwpState, type, len, buf);
+}
+