static bool initFieldOffset(ClassObject* clazz, int *pOffset,
const char* name, const char* type) {
int offset = dvmFindFieldOffset(clazz, name, type);
if (offset < 0) {
ALOGE("Could not find essential field %s.%s of type %s", clazz->descriptor, name, type);
return false;
}
*pOffset = offset;
return true;
}
/*
* Initialize string globals.
*
* This isn't part of the VM init sequence because it's hard to get the
* timing right -- we need it to happen after java/lang/String has been
* loaded, but before anybody wants to use a string. It's easiest to
* just initialize it on first use.
*
* In some unusual circumstances (e.g. trying to throw an exception because
* String implements java/lang/CharSequence, but CharSequence doesn't exist)
* we can try to create an exception string internally before anything has
* really tried to use String. In that case we basically self-destruct.
*/
static bool stringStartup()
{
if (gDvm.javaLangStringReady < 0) {
LOGE("ERROR: reentrant string initialization\n");
assert(false);
return false;
}
assert(gDvm.javaLangStringReady == 0);
gDvm.javaLangStringReady = -1;
if (gDvm.classJavaLangString == NULL)
gDvm.classJavaLangString =
dvmFindSystemClassNoInit("Ljava/lang/String;");
gDvm.offJavaLangString_value =
dvmFindFieldOffset(gDvm.classJavaLangString, "value", "[C");
gDvm.offJavaLangString_count =
dvmFindFieldOffset(gDvm.classJavaLangString, "count", "I");
gDvm.offJavaLangString_offset =
dvmFindFieldOffset(gDvm.classJavaLangString, "offset", "I");
gDvm.offJavaLangString_hashCode =
dvmFindFieldOffset(gDvm.classJavaLangString, "hashCode", "I");
if (gDvm.offJavaLangString_value < 0 ||
gDvm.offJavaLangString_count < 0 ||
gDvm.offJavaLangString_offset < 0 ||
gDvm.offJavaLangString_hashCode < 0)
{
LOGE("VM-required field missing from java/lang/String\n");
return false;
}
gDvm.javaLangStringReady = 1;
return true;
}
/*
* This is the constructor for a generated proxy object.
*/
static void proxyConstructor(const u4* args, JValue* pResult,
const Method* method, Thread* self)
{
Object* obj = (Object*) args[0];
Object* handler = (Object*) args[1];
ClassObject* clazz = obj->clazz;
int fieldOffset;
fieldOffset = dvmFindFieldOffset(clazz, "h",
"Ljava/lang/reflect/InvocationHandler;");
if (fieldOffset < 0) {
LOGE("Unable to find 'h' in Proxy object\n");
//dvmDumpClass(clazz, kDumpClassFullDetail);
dvmAbort(); // this should never happen
}
dvmSetFieldObject(obj, fieldOffset, handler);
}
/*
* This is the common message body for proxy methods.
*
* The method we're calling looks like:
* public Object invoke(Object proxy, Method method, Object[] args)
*
* This means we have to create a Method object, box our arguments into
* a new Object[] array, make the call, and unbox the return value if
* necessary.
*/
static void proxyInvoker(const u4* args, JValue* pResult,
const Method* method, Thread* self)
{
Object* thisObj = (Object*) args[0];
Object* methodObj = NULL;
ArrayObject* argArray = NULL;
Object* handler;
Method* invoke;
ClassObject* returnType;
int hOffset;
JValue invokeResult;
/*
* Retrieve handler object for this proxy instance.
*/
hOffset = dvmFindFieldOffset(thisObj->clazz, "h",
"Ljava/lang/reflect/InvocationHandler;");
if (hOffset < 0) {
LOGE("Unable to find 'h' in Proxy object\n");
dvmAbort();
}
handler = dvmGetFieldObject(thisObj, hOffset);
/*
* Find the invoke() method, looking in "this"s class. (Because we
* start here we don't have to convert it to a vtable index and then
* index into this' vtable.)
*/
invoke = dvmFindVirtualMethodHierByDescriptor(handler->clazz, "invoke",
"(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;");
if (invoke == NULL) {
LOGE("Unable to find invoke()\n");
dvmAbort();
}
LOGV("invoke: %s.%s, this=%p, handler=%s\n",
method->clazz->descriptor, method->name,
thisObj, handler->clazz->descriptor);
/*
* Create a java.lang.reflect.Method object for this method.
*
* We don't want to use "method", because that's the concrete
* implementation in the proxy class. We want the abstract Method
* from the declaring interface. We have a pointer to it tucked
* away in the "insns" field.
*
* TODO: this could be cached for performance.
*/
methodObj = dvmCreateReflectMethodObject((Method*) method->insns);
if (methodObj == NULL) {
assert(dvmCheckException(self));
goto bail;
}
/*
* Determine the return type from the signature.
*
* TODO: this could be cached for performance.
*/
returnType = dvmGetBoxedReturnType(method);
if (returnType == NULL) {
char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
LOGE("Could not determine return type for '%s'\n", desc);
free(desc);
assert(dvmCheckException(self));
goto bail;
}
LOGV(" return type will be %s\n", returnType->descriptor);
/*
* Convert "args" array into Object[] array, using the method
* signature to determine types. If the method takes no arguments,
* we must pass null.
*/
argArray = boxMethodArgs(method, args+1);
if (dvmCheckException(self))
goto bail;
/*
* Call h.invoke(proxy, method, args).
*
* We don't need to repackage exceptions, so if one has been thrown
* just jump to the end.
*/
dvmCallMethod(self, invoke, handler, &invokeResult,
thisObj, methodObj, argArray);
if (dvmCheckException(self))
goto bail;
/*
* Unbox the return value. If it's the wrong type, throw a
* ClassCastException. If it's a null pointer and we need a
* primitive type, throw a NullPointerException.
*/
if (returnType->primitiveType == PRIM_VOID) {
LOGVV("+++ ignoring return to void\n");
} else if (invokeResult.l == NULL) {
if (dvmIsPrimitiveClass(returnType)) {
dvmThrowException("Ljava/lang/NullPointerException;",
"null result when primitive expected");
goto bail;
}
pResult->l = NULL;
} else {
if (!dvmUnwrapPrimitive(invokeResult.l, returnType, pResult)) {
dvmThrowExceptionWithClassMessage("Ljava/lang/ClassCastException;",
((Object*)invokeResult.l)->clazz->descriptor);
goto bail;
}
}
bail:
dvmReleaseTrackedAlloc(methodObj, self);
dvmReleaseTrackedAlloc((Object*)argArray, self);
}
/*
* "buf" contains a full JDWP packet, possibly with multiple chunks. We
* need to process each, accumulate the replies, and ship the whole thing
* back.
*
* Returns "true" if we have a reply. The reply buffer is newly allocated,
* and includes the chunk type/length, followed by the data.
*
* TODO: we currently assume that the request and reply include a single
* chunk. If this becomes inconvenient we will need to adapt.
*/
bool dvmDdmHandlePacket(const u1* buf, int dataLen, u1** pReplyBuf,
int* pReplyLen)
{
Thread* self = dvmThreadSelf();
const int kChunkHdrLen = 8;
ArrayObject* dataArray = NULL;
bool result = false;
assert(dataLen >= 0);
/*
* Prep DdmServer. We could throw this in gDvm.
*/
ClassObject* ddmServerClass;
Method* dispatch;
ddmServerClass =
dvmFindClass("Lorg/apache/harmony/dalvik/ddmc/DdmServer;", NULL);
if (ddmServerClass == NULL) {
LOGW("Unable to find org.apache.harmony.dalvik.ddmc.DdmServer\n");
goto bail;
}
dispatch = dvmFindDirectMethodByDescriptor(ddmServerClass, "dispatch",
"(I[BII)Lorg/apache/harmony/dalvik/ddmc/Chunk;");
if (dispatch == NULL) {
LOGW("Unable to find DdmServer.dispatch\n");
goto bail;
}
/*
* Prep Chunk.
*/
int chunkTypeOff, chunkDataOff, chunkOffsetOff, chunkLengthOff;
ClassObject* chunkClass;
chunkClass = dvmFindClass("Lorg/apache/harmony/dalvik/ddmc/Chunk;", NULL);
if (chunkClass == NULL) {
LOGW("Unable to find org.apache.harmony.dalvik.ddmc.Chunk\n");
goto bail;
}
chunkTypeOff = dvmFindFieldOffset(chunkClass, "type", "I");
chunkDataOff = dvmFindFieldOffset(chunkClass, "data", "[B");
chunkOffsetOff = dvmFindFieldOffset(chunkClass, "offset", "I");
chunkLengthOff = dvmFindFieldOffset(chunkClass, "length", "I");
if (chunkTypeOff < 0 || chunkDataOff < 0 ||
chunkOffsetOff < 0 || chunkLengthOff < 0)
{
LOGW("Unable to find all chunk fields\n");
goto bail;
}
/*
* The chunk handlers are written in the Java programming language, so
* we need to convert the buffer to a byte array.
*/
dataArray = dvmAllocPrimitiveArray('B', dataLen, ALLOC_DEFAULT);
if (dataArray == NULL) {
LOGW("array alloc failed (%d)\n", dataLen);
dvmClearException(self);
goto bail;
}
memcpy(dataArray->contents, buf, dataLen);
/*
* Run through and find all chunks. [Currently just find the first.]
*/
unsigned int offset, length, type;
type = get4BE((u1*)dataArray->contents + 0);
length = get4BE((u1*)dataArray->contents + 4);
offset = kChunkHdrLen;
if (offset+length > (unsigned int) dataLen) {
LOGW("WARNING: bad chunk found (len=%u pktLen=%d)\n", length, dataLen);
goto bail;
}
/*
* Call the handler.
*/
JValue callRes;
dvmCallMethod(self, dispatch, NULL, &callRes, type, dataArray, offset,
length);
if (dvmCheckException(self)) {
LOGI("Exception thrown by dispatcher for 0x%08x\n", type);
dvmLogExceptionStackTrace();
dvmClearException(self);
goto bail;
}
Object* chunk;
ArrayObject* replyData;
chunk = (Object*) callRes.l;
if (chunk == NULL)
goto bail;
/*
* Pull the pieces out of the chunk. We copy the results into a
* newly-allocated buffer that the caller can free. We don't want to
* continue using the Chunk object because nothing has a reference to it.
* (If we do an alloc in here, we need to dvmAddTrackedAlloc it.)
*
* We could avoid this by returning type/data/offset/length and having
* the caller be aware of the object lifetime issues, but that
* integrates the JDWP code more tightly into the VM, and doesn't work
* if we have responses for multiple chunks.
*
* So we're pretty much stuck with copying data around multiple times.
*/
type = dvmGetFieldInt(chunk, chunkTypeOff);
replyData = (ArrayObject*) dvmGetFieldObject(chunk, chunkDataOff);
offset = dvmGetFieldInt(chunk, chunkOffsetOff);
length = dvmGetFieldInt(chunk, chunkLengthOff);
LOGV("DDM reply: type=0x%08x data=%p offset=%d length=%d\n",
type, replyData, offset, length);
if (length == 0 || replyData == NULL)
goto bail;
if (offset + length > replyData->length) {
LOGW("WARNING: chunk off=%d len=%d exceeds reply array len %d\n",
offset, length, replyData->length);
goto bail;
}
u1* reply;
reply = (u1*) malloc(length + kChunkHdrLen);
if (reply == NULL) {
LOGW("malloc %d failed\n", length+kChunkHdrLen);
goto bail;
}
set4BE(reply + 0, type);
set4BE(reply + 4, length);
memcpy(reply+kChunkHdrLen, (const u1*)replyData->contents + offset, length);
*pReplyBuf = reply;
*pReplyLen = length + kChunkHdrLen;
result = true;
LOGV("dvmHandleDdm returning type=%.4s buf=%p len=%d\n",
(char*) reply, reply, length);
bail:
dvmReleaseTrackedAlloc((Object*) dataArray, NULL);
return result;
}
/*
* Cache pointers to some of the exception classes we use locally.
*
* Note this is NOT called during dexopt optimization. Some of the fields
* are initialized by the verifier (dvmVerifyCodeFlow).
*/
bool dvmExceptionStartup(void)
{
gDvm.classJavaLangThrowable =
dvmFindSystemClassNoInit("Ljava/lang/Throwable;");
gDvm.classJavaLangRuntimeException =
dvmFindSystemClassNoInit("Ljava/lang/RuntimeException;");
gDvm.classJavaLangStackOverflowError =
dvmFindSystemClassNoInit("Ljava/lang/StackOverflowError;");
gDvm.classJavaLangError =
dvmFindSystemClassNoInit("Ljava/lang/Error;");
gDvm.classJavaLangStackTraceElement =
dvmFindSystemClassNoInit("Ljava/lang/StackTraceElement;");
gDvm.classJavaLangStackTraceElementArray =
dvmFindArrayClass("[Ljava/lang/StackTraceElement;", NULL);
if (gDvm.classJavaLangThrowable == NULL ||
gDvm.classJavaLangStackTraceElement == NULL ||
gDvm.classJavaLangStackTraceElementArray == NULL)
{
LOGE("Could not find one or more essential exception classes\n");
return false;
}
/*
* Find the constructor. Note that, unlike other saved method lookups,
* we're using a Method* instead of a vtable offset. This is because
* constructors don't have vtable offsets. (Also, since we're creating
* the object in question, it's impossible for anyone to sub-class it.)
*/
Method* meth;
meth = dvmFindDirectMethodByDescriptor(gDvm.classJavaLangStackTraceElement,
"<init>", "(Ljava/lang/String;Ljava/lang/String;Ljava/lang/String;I)V");
if (meth == NULL) {
LOGE("Unable to find constructor for StackTraceElement\n");
return false;
}
gDvm.methJavaLangStackTraceElement_init = meth;
/* grab an offset for the stackData field */
gDvm.offJavaLangThrowable_stackState =
dvmFindFieldOffset(gDvm.classJavaLangThrowable,
"stackState", "Ljava/lang/Object;");
if (gDvm.offJavaLangThrowable_stackState < 0) {
LOGE("Unable to find Throwable.stackState\n");
return false;
}
/* and one for the message field, in case we want to show it */
gDvm.offJavaLangThrowable_message =
dvmFindFieldOffset(gDvm.classJavaLangThrowable,
"detailMessage", "Ljava/lang/String;");
if (gDvm.offJavaLangThrowable_message < 0) {
LOGE("Unable to find Throwable.detailMessage\n");
return false;
}
/* and one for the cause field, just 'cause */
gDvm.offJavaLangThrowable_cause =
dvmFindFieldOffset(gDvm.classJavaLangThrowable,
"cause", "Ljava/lang/Throwable;");
if (gDvm.offJavaLangThrowable_cause < 0) {
LOGE("Unable to find Throwable.cause\n");
return false;
}
return true;
}
/*
* Initialize string globals.
*
* This isn't part of the VM init sequence because it's hard to get the
* timing right -- we need it to happen after java/lang/String has been
* loaded, but before anybody wants to use a string. It's easiest to
* just initialize it on first use.
*
* In some unusual circumstances (e.g. trying to throw an exception because
* String implements java/lang/CharSequence, but CharSequence doesn't exist)
* we can try to create an exception string internally before anything has
* really tried to use String. In that case we basically self-destruct.
*/
static bool stringStartup()
{
if (gDvm.javaLangStringReady < 0) {
LOGE("ERROR: reentrant string initialization\n");
assert(false);
return false;
}
assert(gDvm.javaLangStringReady == 0);
gDvm.javaLangStringReady = -1;
if (gDvm.classJavaLangString == NULL)
gDvm.classJavaLangString =
dvmFindSystemClassNoInit("Ljava/lang/String;");
gDvm.offJavaLangString_value =
dvmFindFieldOffset(gDvm.classJavaLangString, "value", "[C");
gDvm.offJavaLangString_count =
dvmFindFieldOffset(gDvm.classJavaLangString, "count", "I");
gDvm.offJavaLangString_offset =
dvmFindFieldOffset(gDvm.classJavaLangString, "offset", "I");
gDvm.offJavaLangString_hashCode =
dvmFindFieldOffset(gDvm.classJavaLangString, "hashCode", "I");
if (gDvm.offJavaLangString_value < 0 ||
gDvm.offJavaLangString_count < 0 ||
gDvm.offJavaLangString_offset < 0 ||
gDvm.offJavaLangString_hashCode < 0)
{
LOGE("VM-required field missing from java/lang/String\n");
return false;
}
bool badValue = false;
if (gDvm.offJavaLangString_value != STRING_FIELDOFF_VALUE) {
LOGE("InlineNative: String.value offset = %d, expected %d\n",
gDvm.offJavaLangString_value, STRING_FIELDOFF_VALUE);
badValue = true;
}
if (gDvm.offJavaLangString_count != STRING_FIELDOFF_COUNT) {
LOGE("InlineNative: String.count offset = %d, expected %d\n",
gDvm.offJavaLangString_count, STRING_FIELDOFF_COUNT);
badValue = true;
}
if (gDvm.offJavaLangString_offset != STRING_FIELDOFF_OFFSET) {
LOGE("InlineNative: String.offset offset = %d, expected %d\n",
gDvm.offJavaLangString_offset, STRING_FIELDOFF_OFFSET);
badValue = true;
}
if (gDvm.offJavaLangString_hashCode != STRING_FIELDOFF_HASHCODE) {
LOGE("InlineNative: String.hashCode offset = %d, expected %d\n",
gDvm.offJavaLangString_hashCode, STRING_FIELDOFF_HASHCODE);
badValue = true;
}
if (badValue)
return false;
gDvm.javaLangStringReady = 1;
return true;
}
