/*
* Three possibilities:
* SP_NONE - do nothing
* SP_EVENT_THREAD - suspend ourselves
* SP_ALL - suspend everybody except JDWP support thread
*/
static void suspendByPolicy(JdwpState* state, JdwpSuspendPolicy suspendPolicy)
{
if (suspendPolicy == SP_NONE)
return;
if (suspendPolicy == SP_ALL) {
dvmDbgSuspendVM(true);
} else {
assert(suspendPolicy == SP_EVENT_THREAD);
}
/* this is rare but possible -- see CLASS_PREPARE handling */
if (dvmDbgGetThreadSelfId() == state->debugThreadId) {
ALOGI("NOTE: suspendByPolicy not suspending JDWP thread");
return;
}
DebugInvokeReq* pReq = dvmDbgGetInvokeReq();
while (true) {
pReq->ready = true;
dvmDbgSuspendSelf();
pReq->ready = false;
/*
* The JDWP thread has told us (and possibly all other threads) to
* resume. See if it has left anything in our DebugInvokeReq mailbox.
*/
if (!pReq->invokeNeeded) {
/*LOGD("suspendByPolicy: no invoke needed");*/
break;
}
/* grab this before posting/suspending again */
dvmJdwpSetWaitForEventThread(state, dvmDbgGetThreadSelfId());
/* leave pReq->invokeNeeded raised so we can check reentrancy */
ALOGV("invoking method...");
dvmDbgExecuteMethod(pReq);
pReq->err = ERR_NONE;
/* clear this before signaling */
pReq->invokeNeeded = false;
ALOGV("invoke complete, signaling and self-suspending");
dvmDbgLockMutex(&pReq->lock);
dvmDbgCondSignal(&pReq->cv);
dvmDbgUnlockMutex(&pReq->lock);
}
}
/*
* Tell the debugger that we have finished initializing. This is always
* sent, even if the debugger hasn't requested it.
*
* This should be sent "before the main thread is started and before
* any application code has been executed". The thread ID in the message
* must be for the main thread.
*/
bool dvmJdwpPostVMStart(JdwpState* state, bool suspend)
{
JdwpSuspendPolicy suspendPolicy;
ObjectId threadId = dvmDbgGetThreadSelfId();
if (suspend)
suspendPolicy = SP_ALL;
else
suspendPolicy = SP_NONE;
/* probably don't need this here */
lockEventMutex(state);
ExpandBuf* pReq = NULL;
if (true) {
ALOGV("EVENT: %s", dvmJdwpEventKindStr(EK_VM_START));
ALOGV(" suspendPolicy=%s", dvmJdwpSuspendPolicyStr(suspendPolicy));
pReq = eventPrep();
expandBufAdd1(pReq, suspendPolicy);
expandBufAdd4BE(pReq, 1);
expandBufAdd1(pReq, EK_VM_START);
expandBufAdd4BE(pReq, 0); /* requestId */
expandBufAdd8BE(pReq, threadId);
}
unlockEventMutex(state);
/* send request and possibly suspend ourselves */
if (pReq != NULL) {
int oldStatus = dvmDbgThreadWaiting();
if (suspendPolicy != SP_NONE)
dvmJdwpSetWaitForEventThread(state, threadId);
eventFinish(state, pReq);
suspendByPolicy(state, suspendPolicy);
dvmDbgThreadContinuing(oldStatus);
}
return true;
}
/*
* A thread is starting or stopping.
*
* Valid mods:
* Count, ThreadOnly
*/
bool dvmJdwpPostThreadChange(JdwpState* state, ObjectId threadId, bool start)
{
JdwpSuspendPolicy suspendPolicy = SP_NONE;
assert(threadId == dvmDbgGetThreadSelfId());
/*
* I don't think this can happen.
*/
if (invokeInProgress(state)) {
ALOGW("Not posting thread change during invoke");
return false;
}
ModBasket basket;
memset(&basket, 0, sizeof(basket));
basket.threadId = threadId;
/* don't allow the list to be updated while we scan it */
lockEventMutex(state);
JdwpEvent** matchList = allocMatchList(state);
int matchCount = 0;
if (start)
findMatchingEvents(state, EK_THREAD_START, &basket, matchList,
&matchCount);
else
findMatchingEvents(state, EK_THREAD_DEATH, &basket, matchList,
&matchCount);
ExpandBuf* pReq = NULL;
if (matchCount != 0) {
ALOGV("EVENT: %s(%d total) thread=%llx)",
dvmJdwpEventKindStr(matchList[0]->eventKind), matchCount,
basket.threadId);
suspendPolicy = scanSuspendPolicy(matchList, matchCount);
ALOGV(" suspendPolicy=%s",
dvmJdwpSuspendPolicyStr(suspendPolicy));
pReq = eventPrep();
expandBufAdd1(pReq, suspendPolicy);
expandBufAdd4BE(pReq, matchCount);
for (int i = 0; i < matchCount; i++) {
expandBufAdd1(pReq, matchList[i]->eventKind);
expandBufAdd4BE(pReq, matchList[i]->requestId);
expandBufAdd8BE(pReq, basket.threadId);
}
}
cleanupMatchList(state, matchList, matchCount);
unlockEventMutex(state);
/* send request and possibly suspend ourselves */
if (pReq != NULL) {
int oldStatus = dvmDbgThreadWaiting();
if (suspendPolicy != SP_NONE)
dvmJdwpSetWaitForEventThread(state, basket.threadId);
eventFinish(state, pReq);
suspendByPolicy(state, suspendPolicy);
dvmDbgThreadContinuing(oldStatus);
}
return matchCount != 0;
}
/*
* A location of interest has been reached. This handles:
* Breakpoint
* SingleStep
* MethodEntry
* MethodExit
* These four types must be grouped together in a single response. The
* "eventFlags" indicates the type of event(s) that have happened.
*
* Valid mods:
* Count, ThreadOnly, ClassOnly, ClassMatch, ClassExclude, InstanceOnly
* LocationOnly (for breakpoint/step only)
* Step (for step only)
*
* Interesting test cases:
* - Put a breakpoint on a native method. Eclipse creates METHOD_ENTRY
* and METHOD_EXIT events with a ClassOnly mod on the method's class.
* - Use "run to line". Eclipse creates a BREAKPOINT with Count=1.
* - Single-step to a line with a breakpoint. Should get a single
* event message with both events in it.
*/
bool dvmJdwpPostLocationEvent(JdwpState* state, const JdwpLocation* pLoc,
ObjectId thisPtr, int eventFlags)
{
JdwpSuspendPolicy suspendPolicy = SP_NONE;
ModBasket basket;
char* nameAlloc = NULL;
memset(&basket, 0, sizeof(basket));
basket.pLoc = pLoc;
basket.classId = pLoc->classId;
basket.thisPtr = thisPtr;
basket.threadId = dvmDbgGetThreadSelfId();
basket.className = nameAlloc =
dvmDescriptorToName(dvmDbgGetClassDescriptor(pLoc->classId));
/*
* On rare occasions we may need to execute interpreted code in the VM
* while handling a request from the debugger. Don't fire breakpoints
* while doing so. (I don't think we currently do this at all, so
* this is mostly paranoia.)
*/
if (basket.threadId == state->debugThreadId) {
ALOGV("Ignoring location event in JDWP thread");
free(nameAlloc);
return false;
}
/*
* The debugger variable display tab may invoke the interpreter to format
* complex objects. We want to ignore breakpoints and method entry/exit
* traps while working on behalf of the debugger.
*
* If we don't ignore them, the VM will get hung up, because we'll
* suspend on a breakpoint while the debugger is still waiting for its
* method invocation to complete.
*/
if (invokeInProgress(state)) {
ALOGV("Not checking breakpoints during invoke (%s)", basket.className);
free(nameAlloc);
return false;
}
/* don't allow the list to be updated while we scan it */
lockEventMutex(state);
JdwpEvent** matchList = allocMatchList(state);
int matchCount = 0;
if ((eventFlags & DBG_BREAKPOINT) != 0)
findMatchingEvents(state, EK_BREAKPOINT, &basket, matchList,
&matchCount);
if ((eventFlags & DBG_SINGLE_STEP) != 0)
findMatchingEvents(state, EK_SINGLE_STEP, &basket, matchList,
&matchCount);
if ((eventFlags & DBG_METHOD_ENTRY) != 0)
findMatchingEvents(state, EK_METHOD_ENTRY, &basket, matchList,
&matchCount);
if ((eventFlags & DBG_METHOD_EXIT) != 0)
findMatchingEvents(state, EK_METHOD_EXIT, &basket, matchList,
&matchCount);
ExpandBuf* pReq = NULL;
if (matchCount != 0) {
ALOGV("EVENT: %s(%d total) %s.%s thread=%llx code=%llx)",
dvmJdwpEventKindStr(matchList[0]->eventKind), matchCount,
basket.className,
dvmDbgGetMethodName(pLoc->classId, pLoc->methodId),
basket.threadId, pLoc->idx);
suspendPolicy = scanSuspendPolicy(matchList, matchCount);
ALOGV(" suspendPolicy=%s",
dvmJdwpSuspendPolicyStr(suspendPolicy));
pReq = eventPrep();
expandBufAdd1(pReq, suspendPolicy);
expandBufAdd4BE(pReq, matchCount);
for (int i = 0; i < matchCount; i++) {
expandBufAdd1(pReq, matchList[i]->eventKind);
expandBufAdd4BE(pReq, matchList[i]->requestId);
expandBufAdd8BE(pReq, basket.threadId);
dvmJdwpAddLocation(pReq, pLoc);
}
}
cleanupMatchList(state, matchList, matchCount);
unlockEventMutex(state);
/* send request and possibly suspend ourselves */
if (pReq != NULL) {
int oldStatus = dvmDbgThreadWaiting();
if (suspendPolicy != SP_NONE)
dvmJdwpSetWaitForEventThread(state, basket.threadId);
eventFinish(state, pReq);
suspendByPolicy(state, suspendPolicy);
dvmDbgThreadContinuing(oldStatus);
}
free(nameAlloc);
return matchCount != 0;
}
/*
* Announce that a class has been loaded.
*
* Valid mods:
* Count, ThreadOnly, ClassOnly, ClassMatch, ClassExclude
*/
bool dvmJdwpPostClassPrepare(JdwpState* state, int tag, RefTypeId refTypeId,
const char* signature, int status)
{
JdwpSuspendPolicy suspendPolicy = SP_NONE;
ModBasket basket;
char* nameAlloc = NULL;
memset(&basket, 0, sizeof(basket));
basket.classId = refTypeId;
basket.threadId = dvmDbgGetThreadSelfId();
basket.className = nameAlloc =
dvmDescriptorToName(dvmDbgGetClassDescriptor(basket.classId));
/* suppress class prep caused by debugger */
if (invokeInProgress(state)) {
ALOGV("Not posting class prep caused by invoke (%s)",basket.className);
free(nameAlloc);
return false;
}
/* don't allow the list to be updated while we scan it */
lockEventMutex(state);
JdwpEvent** matchList = allocMatchList(state);
int matchCount = 0;
findMatchingEvents(state, EK_CLASS_PREPARE, &basket, matchList,
&matchCount);
ExpandBuf* pReq = NULL;
if (matchCount != 0) {
ALOGV("EVENT: %s(%d total) thread=%llx)",
dvmJdwpEventKindStr(matchList[0]->eventKind), matchCount,
basket.threadId);
suspendPolicy = scanSuspendPolicy(matchList, matchCount);
ALOGV(" suspendPolicy=%s",
dvmJdwpSuspendPolicyStr(suspendPolicy));
if (basket.threadId == state->debugThreadId) {
/*
* JDWP says that, for a class prep in the debugger thread, we
* should set threadId to null and if any threads were supposed
* to be suspended then we suspend all other threads.
*/
ALOGV(" NOTE: class prepare in debugger thread!");
basket.threadId = 0;
if (suspendPolicy == SP_EVENT_THREAD)
suspendPolicy = SP_ALL;
}
pReq = eventPrep();
expandBufAdd1(pReq, suspendPolicy);
expandBufAdd4BE(pReq, matchCount);
for (int i = 0; i < matchCount; i++) {
expandBufAdd1(pReq, matchList[i]->eventKind);
expandBufAdd4BE(pReq, matchList[i]->requestId);
expandBufAdd8BE(pReq, basket.threadId);
expandBufAdd1(pReq, tag);
expandBufAdd8BE(pReq, refTypeId);
expandBufAddUtf8String(pReq, (const u1*) signature);
expandBufAdd4BE(pReq, status);
}
}
cleanupMatchList(state, matchList, matchCount);
unlockEventMutex(state);
/* send request and possibly suspend ourselves */
if (pReq != NULL) {
int oldStatus = dvmDbgThreadWaiting();
if (suspendPolicy != SP_NONE)
dvmJdwpSetWaitForEventThread(state, basket.threadId);
eventFinish(state, pReq);
suspendByPolicy(state, suspendPolicy);
dvmDbgThreadContinuing(oldStatus);
}
free(nameAlloc);
return matchCount != 0;
}
/*
* An exception has been thrown. It may or may not have been caught.
*
* Valid mods:
* Count, ThreadOnly, ClassOnly, ClassMatch, ClassExclude, LocationOnly,
* ExceptionOnly, InstanceOnly
*
* The "exceptionId" has not been added to the GC-visible object registry,
* because there's a pretty good chance that we're not going to send it
* up the debugger.
*/
bool dvmJdwpPostException(JdwpState* state, const JdwpLocation* pThrowLoc,
ObjectId exceptionId, RefTypeId exceptionClassId,
const JdwpLocation* pCatchLoc, ObjectId thisPtr)
{
JdwpSuspendPolicy suspendPolicy = SP_NONE;
ModBasket basket;
char* nameAlloc = NULL;
memset(&basket, 0, sizeof(basket));
basket.pLoc = pThrowLoc;
basket.classId = pThrowLoc->classId;
basket.threadId = dvmDbgGetThreadSelfId();
basket.className = nameAlloc =
dvmDescriptorToName(dvmDbgGetClassDescriptor(basket.classId));
basket.excepClassId = exceptionClassId;
basket.caught = (pCatchLoc->classId != 0);
basket.thisPtr = thisPtr;
/* don't try to post an exception caused by the debugger */
if (invokeInProgress(state)) {
ALOGV("Not posting exception hit during invoke (%s)",basket.className);
free(nameAlloc);
return false;
}
/* don't allow the list to be updated while we scan it */
lockEventMutex(state);
JdwpEvent** matchList = allocMatchList(state);
int matchCount = 0;
findMatchingEvents(state, EK_EXCEPTION, &basket, matchList, &matchCount);
ExpandBuf* pReq = NULL;
if (matchCount != 0) {
ALOGV("EVENT: %s(%d total) thread=%llx exceptId=%llx caught=%d)",
dvmJdwpEventKindStr(matchList[0]->eventKind), matchCount,
basket.threadId, exceptionId, basket.caught);
ALOGV(" throw: %d %llx %x %lld (%s.%s)", pThrowLoc->typeTag,
pThrowLoc->classId, pThrowLoc->methodId, pThrowLoc->idx,
dvmDbgGetClassDescriptor(pThrowLoc->classId),
dvmDbgGetMethodName(pThrowLoc->classId, pThrowLoc->methodId));
if (pCatchLoc->classId == 0) {
ALOGV(" catch: (not caught)");
} else {
ALOGV(" catch: %d %llx %x %lld (%s.%s)", pCatchLoc->typeTag,
pCatchLoc->classId, pCatchLoc->methodId, pCatchLoc->idx,
dvmDbgGetClassDescriptor(pCatchLoc->classId),
dvmDbgGetMethodName(pCatchLoc->classId, pCatchLoc->methodId));
}
suspendPolicy = scanSuspendPolicy(matchList, matchCount);
ALOGV(" suspendPolicy=%s",
dvmJdwpSuspendPolicyStr(suspendPolicy));
pReq = eventPrep();
expandBufAdd1(pReq, suspendPolicy);
expandBufAdd4BE(pReq, matchCount);
for (int i = 0; i < matchCount; i++) {
expandBufAdd1(pReq, matchList[i]->eventKind);
expandBufAdd4BE(pReq, matchList[i]->requestId);
expandBufAdd8BE(pReq, basket.threadId);
dvmJdwpAddLocation(pReq, pThrowLoc);
expandBufAdd1(pReq, JT_OBJECT);
expandBufAdd8BE(pReq, exceptionId);
dvmJdwpAddLocation(pReq, pCatchLoc);
}
/* don't let the GC discard it */
dvmDbgRegisterObjectId(exceptionId);
}
cleanupMatchList(state, matchList, matchCount);
unlockEventMutex(state);
/* send request and possibly suspend ourselves */
if (pReq != NULL) {
int oldStatus = dvmDbgThreadWaiting();
if (suspendPolicy != SP_NONE)
dvmJdwpSetWaitForEventThread(state, basket.threadId);
eventFinish(state, pReq);
suspendByPolicy(state, suspendPolicy);
dvmDbgThreadContinuing(oldStatus);
}
free(nameAlloc);
return matchCount != 0;
}
/*
* Entry point for JDWP thread. The thread was created through the VM
* mechanisms, so there is a java/lang/Thread associated with us.
*/
static void* jdwpThreadStart(void* arg)
{
JdwpState* state = (JdwpState*) arg;
LOGV("JDWP: thread running\n");
/*
* Finish initializing "state", then notify the creating thread that
* we're running.
*/
state->debugThreadHandle = dvmThreadSelf()->handle;
state->run = true;
android_atomic_release_store(true, &state->debugThreadStarted);
dvmDbgLockMutex(&state->threadStartLock);
dvmDbgCondBroadcast(&state->threadStartCond);
dvmDbgUnlockMutex(&state->threadStartLock);
/* set the thread state to VMWAIT so GCs don't wait for us */
dvmDbgThreadWaiting();
/*
* Loop forever if we're in server mode, processing connections. In
* non-server mode, we bail out of the thread when the debugger drops
* us.
*
* We broadcast a notification when a debugger attaches, after we
* successfully process the handshake.
*/
while (state->run) {
bool first;
if (state->params.server) {
/*
* Block forever, waiting for a connection. To support the
* "timeout=xxx" option we'll need to tweak this.
*/
if (!dvmJdwpAcceptConnection(state))
break;
} else {
/*
* If we're not acting as a server, we need to connect out to the
* debugger. To support the "timeout=xxx" option we need to
* have a timeout if the handshake reply isn't received in a
* reasonable amount of time.
*/
if (!dvmJdwpEstablishConnection(state)) {
/* wake anybody who was waiting for us to succeed */
dvmDbgLockMutex(&state->attachLock);
dvmDbgCondBroadcast(&state->attachCond);
dvmDbgUnlockMutex(&state->attachLock);
break;
}
}
/* prep debug code to handle the new connection */
dvmDbgConnected();
/* process requests until the debugger drops */
first = true;
while (true) {
// sanity check -- shouldn't happen?
if (dvmThreadSelf()->status != THREAD_VMWAIT) {
LOGE("JDWP thread no longer in VMWAIT (now %d); resetting\n",
dvmThreadSelf()->status);
dvmDbgThreadWaiting();
}
if (!dvmJdwpProcessIncoming(state)) /* blocking read */
break;
if (first && !dvmJdwpAwaitingHandshake(state)) {
/* handshake worked, tell the interpreter that we're active */
first = false;
/* set thread ID; requires object registry to be active */
state->debugThreadId = dvmDbgGetThreadSelfId();
/* wake anybody who's waiting for us */
dvmDbgLockMutex(&state->attachLock);
dvmDbgCondBroadcast(&state->attachCond);
dvmDbgUnlockMutex(&state->attachLock);
}
}
dvmJdwpCloseConnection(state);
if (state->ddmActive) {
state->ddmActive = false;
/* broadcast the disconnect; must be in RUNNING state */
dvmDbgThreadRunning();
dvmDbgDdmDisconnected();
dvmDbgThreadWaiting();
}
/* release session state, e.g. remove breakpoint instructions */
dvmJdwpResetState(state);
/* tell the interpreter that the debugger is no longer around */
dvmDbgDisconnected();
/* if we had threads suspended, resume them now */
dvmUndoDebuggerSuspensions();
/* if we connected out, this was a one-shot deal */
if (!state->params.server)
state->run = false;
}
/* back to running, for thread shutdown */
dvmDbgThreadRunning();
LOGV("JDWP: thread exiting\n");
return NULL;
}
