/*
* 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.
*/
/*
* JDWP initialization.
*/
#include "jdwp/JdwpPriv.h"
#include "Dalvik.h"
#include "Atomic.h"
#include <stdlib.h>
#include <unistd.h>
#include <sys/time.h>
#include <time.h>
#include <errno.h>
static void* jdwpThreadStart(void* arg);
/*
* Initialize JDWP.
*
* Does not return until JDWP thread is running, but may return before
* the thread is accepting network connections.
*/
JdwpState* dvmJdwpStartup(const JdwpStartupParams* pParams)
{
JdwpState* state = NULL;
int i, sleepIter;
u8 startWhen;
/* comment this out when debugging JDWP itself */
android_setMinPriority(LOG_TAG, ANDROID_LOG_DEBUG);
state = (JdwpState*) calloc(1, sizeof(JdwpState));
state->params = *pParams;
state->requestSerial = 0x10000000;
state->eventSerial = 0x20000000;
dvmDbgInitMutex(&state->threadStartLock);
dvmDbgInitMutex(&state->attachLock);
dvmDbgInitMutex(&state->serialLock);
dvmDbgInitMutex(&state->eventLock);
state->eventThreadId = 0;
dvmDbgInitMutex(&state->eventThreadLock);
dvmDbgInitCond(&state->threadStartCond);
dvmDbgInitCond(&state->attachCond);
dvmDbgInitCond(&state->eventThreadCond);
switch (pParams->transport) {
case kJdwpTransportSocket:
// LOGD("prepping for JDWP over TCP\n");
state->transport = dvmJdwpSocketTransport();
break;
case kJdwpTransportAndroidAdb:
// LOGD("prepping for JDWP over ADB\n");
state->transport = dvmJdwpAndroidAdbTransport();
/* TODO */
break;
default:
LOGE("Unknown transport %d\n", pParams->transport);
assert(false);
goto fail;
}
if (!dvmJdwpNetStartup(state, pParams))
goto fail;
/*
* Grab a mutex or two before starting the thread. This ensures they
* won't signal the cond var before we're waiting.
*/
dvmDbgLockMutex(&state->threadStartLock);
if (pParams->suspend)
dvmDbgLockMutex(&state->attachLock);
/*
* We have bound to a port, or are trying to connect outbound to a
* debugger. Create the JDWP thread and let it continue the mission.
*/
if (!dvmCreateInternalThread(&state->debugThreadHandle, "JDWP",
jdwpThreadStart, state))
{
/* state is getting tossed, but unlock these anyway for cleanliness */
dvmDbgUnlockMutex(&state->threadStartLock);
if (pParams->suspend)
dvmDbgUnlockMutex(&state->attachLock);
goto fail;
}
/*
* Wait until the thread finishes basic initialization.
* TODO: cond vars should be waited upon in a loop
*/
dvmDbgCondWait(&state->threadStartCond, &state->threadStartLock);
dvmDbgUnlockMutex(&state->threadStartLock);
/*
* For suspend=y, wait for the debugger to connect to us or for us to
* connect to the debugger.
*
* The JDWP thread will signal us when it connects successfully or
* times out (for timeout=xxx), so we have to check to see what happened
* when we wake up.
*/
if (pParams->suspend) {
dvmChangeStatus(NULL, THREAD_VMWAIT);
dvmDbgCondWait(&state->attachCond, &state->attachLock);
dvmDbgUnlockMutex(&state->attachLock);
dvmChangeStatus(NULL, THREAD_RUNNING);
if (!dvmJdwpIsActive(state)) {
LOGE("JDWP connection failed\n");
goto fail;
}
LOGI("JDWP connected\n");
/*
* Ordinarily we would pause briefly to allow the debugger to set
* breakpoints and so on, but for "suspend=y" the VM init code will
* pause the VM when it sends the VM_START message.
*/
}
return state;
fail:
dvmJdwpShutdown(state); // frees state
return NULL;
}
/*
* Reset all session-related state. There should not be an active connection
* to the client at this point. The rest of the VM still thinks there is
* a debugger attached.
*
* This includes freeing up the debugger event list.
*/
void dvmJdwpResetState(JdwpState* state)
{
/* could reset the serial numbers, but no need to */
dvmJdwpUnregisterAll(state);
assert(state->eventList == NULL);
/*
* Should not have one of these in progress. If the debugger went away
* mid-request, though, we could see this.
*/
if (state->eventThreadId != 0) {
LOGW("WARNING: resetting state while event in progress\n");
assert(false);
}
}
/*
* Tell the JDWP thread to shut down. Frees "state".
*/
void dvmJdwpShutdown(JdwpState* state)
{
void* threadReturn;
if (state == NULL)
return;
if (dvmJdwpIsTransportDefined(state)) {
if (dvmJdwpIsConnected(state))
dvmJdwpPostVMDeath(state);
/*
* Close down the network to inspire the thread to halt.
*/
if (gDvm.verboseShutdown)
LOGD("JDWP shutting down net...\n");
dvmJdwpNetShutdown(state);
if (state->debugThreadStarted) {
state->run = false;
if (pthread_join(state->debugThreadHandle, &threadReturn) != 0) {
LOGW("JDWP thread join failed\n");
}
}
if (gDvm.verboseShutdown)
LOGD("JDWP freeing netstate...\n");
dvmJdwpNetFree(state);
state->netState = NULL;
}
assert(state->netState == NULL);
dvmJdwpResetState(state);
free(state);
}
/*
* Are we talking to a debugger?
*/
bool dvmJdwpIsActive(JdwpState* state)
{
return dvmJdwpIsConnected(state);
}
/*
* 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;
MEM_BARRIER();
state->debugThreadStarted = true; // touch this last
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;
int cc;
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;
}
/*
* Return the thread handle, or (pthread_t)0 if the debugger isn't running.
*/
pthread_t dvmJdwpGetDebugThread(JdwpState* state)
{
if (state == NULL)
return 0;
return state->debugThreadHandle;
}
#if 0
/*
* Wait until the debugger attaches. Returns immediately if the debugger
* is already attached.
*
* If we return the instant the debugger connects, we run the risk of
* executing code before the debugger has had a chance to configure
* breakpoints or issue suspend calls. It would be nice to just sit in
* the suspended state, but most debuggers don't expect any threads to be
* suspended when they attach.
*
* There's no event we can post to tell the debugger "we've stopped, and
* we like it that way". We could send a fake breakpoint, which should
* cause the debugger to immediately send a resume, but the debugger might
* send the resume immediately or might throw an exception of its own upon
* receiving a breakpoint event that it didn't ask for.
*
* What we really want is a "wait until the debugger is done configuring
* stuff" event. We can get close with a "wait until the debugger has
* been idle for a brief period", and we can do a mild approximation with
* "just sleep for a second after it connects".
*
* We should be in THREAD_VMWAIT here, so we're not allowed to do anything
* with objects because a GC could be in progress.
*
* NOTE: this trips as soon as something connects to the socket. This
* is no longer appropriate -- we don't want to return when DDMS connects.
* We could fix this by polling for the first debugger packet, but we have
* to watch out for disconnects. If we're going to do polling, it's
* probably best to do it at a higher level.
*/
void dvmJdwpWaitForDebugger(JdwpState* state)
{
// no more
}
#endif
/*
* Get a notion of the current time, in milliseconds. We leave it in
* two 32-bit pieces.
*/
void dvmJdwpGetNowMsec(long* pSec, long* pMsec)
{
#ifdef HAVE_POSIX_CLOCKS
struct timespec now;
clock_gettime(CLOCK_MONOTONIC, &now);
*pSec = now.tv_sec;
*pMsec = now.tv_nsec / 1000000;
#else
struct timeval now;
gettimeofday(&now, NULL);
*pSec = now.tv_sec;
*pMsec = now.tv_usec / 1000;
#endif
}
/*
* Return the time, in milliseconds, since the last debugger activity.
*
* Returns -1 if no debugger is attached, or 0 if we're in the middle of
* processing a debugger request.
*/
s8 dvmJdwpLastDebuggerActivity(JdwpState* state)
{
long lastSec, lastMsec;
long nowSec, nowMsec;
/* these are volatile; lastSec becomes 0 during update */
lastSec = state->lastActivitySec;
lastMsec = state->lastActivityMsec;
/* initializing or in the middle of something? */
if (lastSec == 0 || state->lastActivitySec != lastSec) {
//LOGI("+++ last=busy\n");
return 0;
}
/* get the current time *after* latching the "last" time */
dvmJdwpGetNowMsec(&nowSec, &nowMsec);
s8 last = (s8)lastSec * 1000 + lastMsec;
s8 now = (s8)nowSec * 1000 + nowMsec;
//LOGI("last is %ld.%ld --> %lld\n", lastSec, lastMsec, last);
//LOGI("now is %ld.%ld --> %lld\n", nowSec, nowMsec, now);
//LOGI("+++ interval=%lld\n", now - last);
return now - last;
}