| /* |
| * 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. |
| */ |
| |
| #include "jdwp/jdwp_event.h" |
| |
| #include <stddef.h> /* for offsetof() */ |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include "base/logging.h" |
| #include "base/stringprintf.h" |
| #include "debugger.h" |
| #include "jdwp/jdwp_constants.h" |
| #include "jdwp/jdwp_expand_buf.h" |
| #include "jdwp/jdwp_priv.h" |
| #include "thread-inl.h" |
| |
| /* |
| General notes: |
| |
| The event add/remove stuff usually happens from the debugger thread, |
| in response to requests from the debugger, but can also happen as the |
| result of an event in an arbitrary thread (e.g. an event with a "count" |
| mod expires). It's important to keep the event list locked when processing |
| events. |
| |
| Event posting can happen from any thread. The JDWP thread will not usually |
| post anything but VM start/death, but if a JDWP request causes a class |
| to be loaded, the ClassPrepare event will come from the JDWP thread. |
| |
| |
| We can have serialization issues when we post an event to the debugger. |
| For example, a thread could send an "I hit a breakpoint and am suspending |
| myself" message to the debugger. Before it manages to suspend itself, the |
| debugger's response ("not interested, resume thread") arrives and is |
| processed. We try to resume a thread that hasn't yet suspended. |
| |
| This means that, after posting an event to the debugger, we need to wait |
| for the event thread to suspend itself (and, potentially, all other threads) |
| before processing any additional requests from the debugger. While doing |
| so we need to be aware that multiple threads may be hitting breakpoints |
| or other events simultaneously, so we either need to wait for all of them |
| or serialize the events with each other. |
| |
| The current mechanism works like this: |
| Event thread: |
| - If I'm going to suspend, grab the "I am posting an event" token. Wait |
| for it if it's not currently available. |
| - Post the event to the debugger. |
| - If appropriate, suspend others and then myself. As part of suspending |
| myself, release the "I am posting" token. |
| JDWP thread: |
| - When an event arrives, see if somebody is posting an event. If so, |
| sleep until we can acquire the "I am posting an event" token. Release |
| it immediately and continue processing -- the event we have already |
| received should not interfere with other events that haven't yet |
| been posted. |
| |
| Some care must be taken to avoid deadlock: |
| |
| - thread A and thread B exit near-simultaneously, and post thread-death |
| events with a "suspend all" clause |
| - thread A gets the event token, thread B sits and waits for it |
| - thread A wants to suspend all other threads, but thread B is waiting |
| for the token and can't be suspended |
| |
| So we need to mark thread B in such a way that thread A doesn't wait for it. |
| |
| If we just bracket the "grab event token" call with a change to VMWAIT |
| before sleeping, the switch back to RUNNING state when we get the token |
| will cause thread B to suspend (remember, thread A's global suspend is |
| still in force, even after it releases the token). Suspending while |
| holding the event token is very bad, because it prevents the JDWP thread |
| from processing incoming messages. |
| |
| We need to change to VMWAIT state at the *start* of posting an event, |
| and stay there until we either finish posting the event or decide to |
| put ourselves to sleep. That way we don't interfere with anyone else and |
| don't allow anyone else to interfere with us. |
| */ |
| |
| |
| #define kJdwpEventCommandSet 64 |
| #define kJdwpCompositeCommand 100 |
| |
| namespace art { |
| |
| namespace JDWP { |
| |
| /* |
| * Stuff to compare against when deciding if a mod matches. Only the |
| * values for mods valid for the event being evaluated will be filled in. |
| * The rest will be zeroed. |
| */ |
| struct ModBasket { |
| ModBasket() : pLoc(NULL), threadId(0), classId(0), excepClassId(0), |
| caught(false), fieldTypeID(0), fieldId(0), thisPtr(0) { } |
| |
| const JdwpLocation* pLoc; /* LocationOnly */ |
| std::string className; /* ClassMatch/ClassExclude */ |
| ObjectId threadId; /* ThreadOnly */ |
| RefTypeId classId; /* ClassOnly */ |
| RefTypeId excepClassId; /* ExceptionOnly */ |
| bool caught; /* ExceptionOnly */ |
| RefTypeId fieldTypeID; /* FieldOnly */ |
| FieldId fieldId; /* FieldOnly */ |
| ObjectId thisPtr; /* InstanceOnly */ |
| /* nothing for StepOnly -- handled differently */ |
| }; |
| |
| static bool NeedsFullDeoptimization(JdwpEventKind eventKind) { |
| switch (eventKind) { |
| case EK_METHOD_ENTRY: |
| case EK_METHOD_EXIT: |
| case EK_METHOD_EXIT_WITH_RETURN_VALUE: |
| case EK_SINGLE_STEP: |
| case EK_FIELD_ACCESS: |
| case EK_FIELD_MODIFICATION: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| /* |
| * Add an event to the list. Ordering is not important. |
| * |
| * If something prevents the event from being registered, e.g. it's a |
| * single-step request on a thread that doesn't exist, the event will |
| * not be added to the list, and an appropriate error will be returned. |
| */ |
| JdwpError JdwpState::RegisterEvent(JdwpEvent* pEvent) { |
| CHECK(pEvent != NULL); |
| CHECK(pEvent->prev == NULL); |
| CHECK(pEvent->next == NULL); |
| |
| /* |
| * If one or more "break"-type mods are used, register them with |
| * the interpreter. |
| */ |
| DeoptimizationRequest req; |
| for (int i = 0; i < pEvent->modCount; i++) { |
| const JdwpEventMod* pMod = &pEvent->mods[i]; |
| if (pMod->modKind == MK_LOCATION_ONLY) { |
| /* should only be for Breakpoint, Step, and Exception */ |
| Dbg::WatchLocation(&pMod->locationOnly.loc, &req); |
| } else if (pMod->modKind == MK_STEP) { |
| /* should only be for EK_SINGLE_STEP; should only be one */ |
| JdwpStepSize size = static_cast<JdwpStepSize>(pMod->step.size); |
| JdwpStepDepth depth = static_cast<JdwpStepDepth>(pMod->step.depth); |
| JdwpError status = Dbg::ConfigureStep(pMod->step.threadId, size, depth); |
| if (status != ERR_NONE) { |
| return status; |
| } |
| } |
| } |
| if (NeedsFullDeoptimization(pEvent->eventKind)) { |
| CHECK_EQ(req.kind, DeoptimizationRequest::kNothing); |
| CHECK(req.method == nullptr); |
| req.kind = DeoptimizationRequest::kFullDeoptimization; |
| } |
| |
| { |
| /* |
| * Add to list. |
| */ |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| if (event_list_ != NULL) { |
| pEvent->next = event_list_; |
| event_list_->prev = pEvent; |
| } |
| event_list_ = pEvent; |
| ++event_list_size_; |
| } |
| |
| // TODO we can do better job here since we should process only one request: the one we just |
| // created. |
| Dbg::RequestDeoptimization(req); |
| Dbg::ManageDeoptimization(); |
| |
| return ERR_NONE; |
| } |
| |
| /* |
| * Remove an event from the list. This will also remove the event from |
| * any optimization tables, e.g. breakpoints. |
| * |
| * Does not free the JdwpEvent. |
| * |
| * Grab the eventLock before calling here. |
| */ |
| void JdwpState::UnregisterEvent(JdwpEvent* pEvent) { |
| if (pEvent->prev == NULL) { |
| /* head of the list */ |
| CHECK(event_list_ == pEvent); |
| |
| event_list_ = pEvent->next; |
| } else { |
| pEvent->prev->next = pEvent->next; |
| } |
| |
| if (pEvent->next != NULL) { |
| pEvent->next->prev = pEvent->prev; |
| pEvent->next = NULL; |
| } |
| pEvent->prev = NULL; |
| |
| /* |
| * Unhook us from the interpreter, if necessary. |
| */ |
| DeoptimizationRequest req; |
| for (int i = 0; i < pEvent->modCount; i++) { |
| JdwpEventMod* pMod = &pEvent->mods[i]; |
| if (pMod->modKind == MK_LOCATION_ONLY) { |
| /* should only be for Breakpoint, Step, and Exception */ |
| Dbg::UnwatchLocation(&pMod->locationOnly.loc, &req); |
| } |
| if (pMod->modKind == MK_STEP) { |
| /* should only be for EK_SINGLE_STEP; should only be one */ |
| Dbg::UnconfigureStep(pMod->step.threadId); |
| } |
| } |
| if (pEvent->eventKind == EK_SINGLE_STEP) { |
| // Special case for single-steps where we want to avoid the slow pattern deoptimize/undeoptimize |
| // loop between each single-step. In a IDE, this would happens each time the user click on the |
| // "single-step" button. Here we delay the full undeoptimization to the next resume |
| // (VM.Resume or ThreadReference.Resume) or the end of the debugging session (VM.Dispose or |
| // runtime shutdown). |
| // Therefore, in a singles-stepping sequence, only the first single-step will trigger a full |
| // deoptimization and only the last single-step will trigger a full undeoptimization. |
| Dbg::DelayFullUndeoptimization(); |
| } else if (NeedsFullDeoptimization(pEvent->eventKind)) { |
| CHECK_EQ(req.kind, DeoptimizationRequest::kNothing); |
| CHECK(req.method == nullptr); |
| req.kind = DeoptimizationRequest::kFullUndeoptimization; |
| } |
| |
| --event_list_size_; |
| CHECK(event_list_size_ != 0 || event_list_ == NULL); |
| |
| Dbg::RequestDeoptimization(req); |
| } |
| |
| /* |
| * Remove the event with the given ID from the list. |
| * |
| * Failure to find the event isn't really an error, but it is a little |
| * weird. (It looks like Eclipse will try to be extra careful and will |
| * explicitly remove one-off single-step events.) |
| */ |
| void JdwpState::UnregisterEventById(uint32_t requestId) { |
| bool found = false; |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| |
| for (JdwpEvent* pEvent = event_list_; pEvent != nullptr; pEvent = pEvent->next) { |
| if (pEvent->requestId == requestId) { |
| found = true; |
| UnregisterEvent(pEvent); |
| EventFree(pEvent); |
| break; /* there can be only one with a given ID */ |
| } |
| } |
| } |
| |
| if (found) { |
| Dbg::ManageDeoptimization(); |
| } else { |
| LOG(DEBUG) << StringPrintf("Odd: no match when removing event reqId=0x%04x", requestId); |
| } |
| } |
| |
| /* |
| * Remove all entries from the event list. |
| */ |
| void JdwpState::UnregisterAll() { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| |
| JdwpEvent* pEvent = event_list_; |
| while (pEvent != NULL) { |
| JdwpEvent* pNextEvent = pEvent->next; |
| |
| UnregisterEvent(pEvent); |
| EventFree(pEvent); |
| pEvent = pNextEvent; |
| } |
| |
| event_list_ = NULL; |
| } |
| |
| /* |
| * Allocate a JdwpEvent struct with enough space to hold the specified |
| * number of mod records. |
| */ |
| JdwpEvent* EventAlloc(int numMods) { |
| JdwpEvent* newEvent; |
| int allocSize = offsetof(JdwpEvent, mods) + numMods * sizeof(newEvent->mods[0]); |
| newEvent = reinterpret_cast<JdwpEvent*>(malloc(allocSize)); |
| memset(newEvent, 0, allocSize); |
| return newEvent; |
| } |
| |
| /* |
| * Free a JdwpEvent. |
| * |
| * Do not call this until the event has been removed from the list. |
| */ |
| void EventFree(JdwpEvent* pEvent) { |
| if (pEvent == NULL) { |
| return; |
| } |
| |
| /* make sure it was removed from the list */ |
| CHECK(pEvent->prev == NULL); |
| CHECK(pEvent->next == NULL); |
| /* want to check state->event_list_ != pEvent */ |
| |
| /* |
| * Free any hairy bits in the mods. |
| */ |
| for (int i = 0; i < pEvent->modCount; i++) { |
| if (pEvent->mods[i].modKind == MK_CLASS_MATCH) { |
| free(pEvent->mods[i].classMatch.classPattern); |
| pEvent->mods[i].classMatch.classPattern = NULL; |
| } |
| if (pEvent->mods[i].modKind == MK_CLASS_EXCLUDE) { |
| free(pEvent->mods[i].classExclude.classPattern); |
| pEvent->mods[i].classExclude.classPattern = NULL; |
| } |
| } |
| |
| free(pEvent); |
| } |
| |
| /* |
| * Allocate storage for matching events. To keep things simple we |
| * use an array with enough storage for the entire list. |
| * |
| * The state->eventLock should be held before calling. |
| */ |
| static JdwpEvent** AllocMatchList(size_t event_count) { |
| return new JdwpEvent*[event_count]; |
| } |
| |
| /* |
| * Run through the list and remove any entries with an expired "count" mod |
| * from the event list, then free the match list. |
| */ |
| void JdwpState::CleanupMatchList(JdwpEvent** match_list, int match_count) { |
| JdwpEvent** ppEvent = match_list; |
| |
| while (match_count--) { |
| JdwpEvent* pEvent = *ppEvent; |
| |
| for (int i = 0; i < pEvent->modCount; i++) { |
| if (pEvent->mods[i].modKind == MK_COUNT && pEvent->mods[i].count.count == 0) { |
| VLOG(jdwp) << "##### Removing expired event"; |
| UnregisterEvent(pEvent); |
| EventFree(pEvent); |
| break; |
| } |
| } |
| |
| ppEvent++; |
| } |
| |
| delete[] match_list; |
| } |
| |
| /* |
| * Match a string against a "restricted regular expression", which is just |
| * a string that may start or end with '*' (e.g. "*.Foo" or "java.*"). |
| * |
| * ("Restricted name globbing" might have been a better term.) |
| */ |
| static bool PatternMatch(const char* pattern, const std::string& target) { |
| size_t patLen = strlen(pattern); |
| if (pattern[0] == '*') { |
| patLen--; |
| if (target.size() < patLen) { |
| return false; |
| } |
| return strcmp(pattern+1, target.c_str() + (target.size()-patLen)) == 0; |
| } else if (pattern[patLen-1] == '*') { |
| return strncmp(pattern, target.c_str(), patLen-1) == 0; |
| } else { |
| return strcmp(pattern, target.c_str()) == 0; |
| } |
| } |
| |
| /* |
| * See if the event's mods match up with the contents of "basket". |
| * |
| * If we find a Count mod before rejecting an event, we decrement it. We |
| * need to do this even if later mods cause us to ignore the event. |
| */ |
| static bool ModsMatch(JdwpEvent* pEvent, ModBasket* basket) |
| SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) { |
| JdwpEventMod* pMod = pEvent->mods; |
| |
| for (int i = pEvent->modCount; i > 0; i--, pMod++) { |
| switch (pMod->modKind) { |
| case MK_COUNT: |
| CHECK_GT(pMod->count.count, 0); |
| pMod->count.count--; |
| if (pMod->count.count > 0) { |
| return false; |
| } |
| break; |
| case MK_CONDITIONAL: |
| CHECK(false); // should not be getting these |
| break; |
| case MK_THREAD_ONLY: |
| if (pMod->threadOnly.threadId != basket->threadId) { |
| return false; |
| } |
| break; |
| case MK_CLASS_ONLY: |
| if (!Dbg::MatchType(basket->classId, pMod->classOnly.refTypeId)) { |
| return false; |
| } |
| break; |
| case MK_CLASS_MATCH: |
| if (!PatternMatch(pMod->classMatch.classPattern, basket->className)) { |
| return false; |
| } |
| break; |
| case MK_CLASS_EXCLUDE: |
| if (PatternMatch(pMod->classMatch.classPattern, basket->className)) { |
| return false; |
| } |
| break; |
| case MK_LOCATION_ONLY: |
| if (pMod->locationOnly.loc != *basket->pLoc) { |
| return false; |
| } |
| break; |
| case MK_EXCEPTION_ONLY: |
| if (pMod->exceptionOnly.refTypeId != 0 && !Dbg::MatchType(basket->excepClassId, pMod->exceptionOnly.refTypeId)) { |
| return false; |
| } |
| if ((basket->caught && !pMod->exceptionOnly.caught) || (!basket->caught && !pMod->exceptionOnly.uncaught)) { |
| return false; |
| } |
| break; |
| case MK_FIELD_ONLY: |
| if (pMod->fieldOnly.fieldId != basket->fieldId) { |
| return false; |
| } |
| if (!Dbg::MatchType(basket->fieldTypeID, pMod->fieldOnly.refTypeId)) { |
| return false; |
| } |
| break; |
| case MK_STEP: |
| if (pMod->step.threadId != basket->threadId) { |
| return false; |
| } |
| break; |
| case MK_INSTANCE_ONLY: |
| if (pMod->instanceOnly.objectId != basket->thisPtr) { |
| return false; |
| } |
| break; |
| default: |
| LOG(FATAL) << "unknown mod kind " << pMod->modKind; |
| break; |
| } |
| } |
| return true; |
| } |
| |
| /* |
| * Find all events of type "eventKind" with mods that match up with the |
| * rest of the arguments. |
| * |
| * Found events are appended to "match_list", and "*pMatchCount" is advanced, |
| * so this may be called multiple times for grouped events. |
| * |
| * DO NOT call this multiple times for the same eventKind, as Count mods are |
| * decremented during the scan. |
| */ |
| void JdwpState::FindMatchingEvents(JdwpEventKind eventKind, ModBasket* basket, |
| JdwpEvent** match_list, int* pMatchCount) { |
| /* start after the existing entries */ |
| match_list += *pMatchCount; |
| |
| JdwpEvent* pEvent = event_list_; |
| while (pEvent != NULL) { |
| if (pEvent->eventKind == eventKind && ModsMatch(pEvent, basket)) { |
| *match_list++ = pEvent; |
| (*pMatchCount)++; |
| } |
| |
| pEvent = pEvent->next; |
| } |
| } |
| |
| /* |
| * Scan through the list of matches and determine the most severe |
| * suspension policy. |
| */ |
| static JdwpSuspendPolicy scanSuspendPolicy(JdwpEvent** match_list, int match_count) { |
| JdwpSuspendPolicy policy = SP_NONE; |
| |
| while (match_count--) { |
| if ((*match_list)->suspend_policy > policy) { |
| policy = (*match_list)->suspend_policy; |
| } |
| match_list++; |
| } |
| |
| return policy; |
| } |
| |
| /* |
| * Three possibilities: |
| * SP_NONE - do nothing |
| * SP_EVENT_THREAD - suspend ourselves |
| * SP_ALL - suspend everybody except JDWP support thread |
| */ |
| void JdwpState::SuspendByPolicy(JdwpSuspendPolicy suspend_policy, JDWP::ObjectId thread_self_id) { |
| VLOG(jdwp) << "SuspendByPolicy(" << suspend_policy << ")"; |
| if (suspend_policy == SP_NONE) { |
| return; |
| } |
| |
| if (suspend_policy == SP_ALL) { |
| Dbg::SuspendVM(); |
| } else { |
| CHECK_EQ(suspend_policy, SP_EVENT_THREAD); |
| } |
| |
| /* this is rare but possible -- see CLASS_PREPARE handling */ |
| if (thread_self_id == debug_thread_id_) { |
| LOG(INFO) << "NOTE: SuspendByPolicy not suspending JDWP thread"; |
| return; |
| } |
| |
| DebugInvokeReq* pReq = Dbg::GetInvokeReq(); |
| while (true) { |
| pReq->ready = true; |
| Dbg::SuspendSelf(); |
| 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->invoke_needed) { |
| /*LOGD("SuspendByPolicy: no invoke needed");*/ |
| break; |
| } |
| |
| /* grab this before posting/suspending again */ |
| SetWaitForEventThread(thread_self_id); |
| |
| /* leave pReq->invoke_needed_ raised so we can check reentrancy */ |
| Dbg::ExecuteMethod(pReq); |
| |
| pReq->error = ERR_NONE; |
| } |
| } |
| |
| void JdwpState::SendRequestAndPossiblySuspend(ExpandBuf* pReq, JdwpSuspendPolicy suspend_policy, |
| ObjectId threadId) { |
| Thread* self = Thread::Current(); |
| self->AssertThreadSuspensionIsAllowable(); |
| /* send request and possibly suspend ourselves */ |
| if (pReq != NULL) { |
| JDWP::ObjectId thread_self_id = Dbg::GetThreadSelfId(); |
| self->TransitionFromRunnableToSuspended(kWaitingForDebuggerSend); |
| if (suspend_policy != SP_NONE) { |
| SetWaitForEventThread(threadId); |
| } |
| EventFinish(pReq); |
| SuspendByPolicy(suspend_policy, thread_self_id); |
| self->TransitionFromSuspendedToRunnable(); |
| } |
| } |
| |
| /* |
| * Determine if there is a method invocation in progress in the current |
| * thread. |
| * |
| * We look at the "invoke_needed" flag in the per-thread DebugInvokeReq |
| * state. If set, we're in the process of invoking a method. |
| */ |
| bool JdwpState::InvokeInProgress() { |
| DebugInvokeReq* pReq = Dbg::GetInvokeReq(); |
| return pReq->invoke_needed; |
| } |
| |
| /* |
| * We need the JDWP thread to hold off on doing stuff while we post an |
| * event and then suspend ourselves. |
| * |
| * Call this with a threadId of zero if you just want to wait for the |
| * current thread operation to complete. |
| * |
| * This could go to sleep waiting for another thread, so it's important |
| * that the thread be marked as VMWAIT before calling here. |
| */ |
| void JdwpState::SetWaitForEventThread(ObjectId threadId) { |
| bool waited = false; |
| |
| /* this is held for very brief periods; contention is unlikely */ |
| Thread* self = Thread::Current(); |
| MutexLock mu(self, event_thread_lock_); |
| |
| /* |
| * If another thread is already doing stuff, wait for it. This can |
| * go to sleep indefinitely. |
| */ |
| while (event_thread_id_ != 0) { |
| VLOG(jdwp) << StringPrintf("event in progress (%#" PRIx64 "), %#" PRIx64 " sleeping", |
| event_thread_id_, threadId); |
| waited = true; |
| event_thread_cond_.Wait(self); |
| } |
| |
| if (waited || threadId != 0) { |
| VLOG(jdwp) << StringPrintf("event token grabbed (%#" PRIx64 ")", threadId); |
| } |
| if (threadId != 0) { |
| event_thread_id_ = threadId; |
| } |
| } |
| |
| /* |
| * Clear the threadId and signal anybody waiting. |
| */ |
| void JdwpState::ClearWaitForEventThread() { |
| /* |
| * Grab the mutex. Don't try to go in/out of VMWAIT mode, as this |
| * function is called by dvmSuspendSelf(), and the transition back |
| * to RUNNING would confuse it. |
| */ |
| Thread* self = Thread::Current(); |
| MutexLock mu(self, event_thread_lock_); |
| |
| CHECK_NE(event_thread_id_, 0U); |
| VLOG(jdwp) << StringPrintf("cleared event token (%#" PRIx64 ")", event_thread_id_); |
| |
| event_thread_id_ = 0; |
| |
| event_thread_cond_.Signal(self); |
| } |
| |
| |
| /* |
| * Prep an event. Allocates storage for the message and leaves space for |
| * the header. |
| */ |
| static ExpandBuf* eventPrep() { |
| ExpandBuf* pReq = expandBufAlloc(); |
| expandBufAddSpace(pReq, kJDWPHeaderLen); |
| return pReq; |
| } |
| |
| /* |
| * Write the header into the buffer and send the packet off to the debugger. |
| * |
| * Takes ownership of "pReq" (currently discards it). |
| */ |
| void JdwpState::EventFinish(ExpandBuf* pReq) { |
| uint8_t* buf = expandBufGetBuffer(pReq); |
| |
| Set4BE(buf, expandBufGetLength(pReq)); |
| Set4BE(buf+4, NextRequestSerial()); |
| Set1(buf+8, 0); /* flags */ |
| Set1(buf+9, kJdwpEventCommandSet); |
| Set1(buf+10, kJdwpCompositeCommand); |
| |
| // Prevents from interleaving commands and events. Otherwise we could end up in sending an event |
| // before sending the reply of the command being processed and would lead to bad synchronization |
| // between the debugger and the debuggee. |
| WaitForProcessingRequest(); |
| |
| SendRequest(pReq); |
| |
| expandBufFree(pReq); |
| } |
| |
| |
| /* |
| * 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 JdwpState::PostVMStart() { |
| JdwpSuspendPolicy suspend_policy; |
| ObjectId threadId = Dbg::GetThreadSelfId(); |
| |
| if (options_->suspend) { |
| suspend_policy = SP_ALL; |
| } else { |
| suspend_policy = SP_NONE; |
| } |
| |
| ExpandBuf* pReq = eventPrep(); |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); // probably don't need this here |
| |
| VLOG(jdwp) << "EVENT: " << EK_VM_START; |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, 1); |
| |
| expandBufAdd1(pReq, EK_VM_START); |
| expandBufAdd4BE(pReq, 0); /* requestId */ |
| expandBufAdd8BE(pReq, threadId); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| /* send request and possibly suspend ourselves */ |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, threadId); |
| |
| return true; |
| } |
| |
| /* |
| * 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 JdwpState::PostLocationEvent(const JdwpLocation* pLoc, ObjectId thisPtr, int eventFlags, |
| const JValue* returnValue) { |
| ModBasket basket; |
| basket.pLoc = pLoc; |
| basket.classId = pLoc->class_id; |
| basket.thisPtr = thisPtr; |
| basket.threadId = Dbg::GetThreadSelfId(); |
| basket.className = Dbg::GetClassName(pLoc->class_id); |
| |
| /* |
| * 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 == debug_thread_id_) { |
| VLOG(jdwp) << "Ignoring location event in JDWP thread"; |
| 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()) { |
| VLOG(jdwp) << "Not checking breakpoints during invoke (" << basket.className << ")"; |
| return false; |
| } |
| |
| int match_count = 0; |
| ExpandBuf* pReq = NULL; |
| JdwpSuspendPolicy suspend_policy = SP_NONE; |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| JdwpEvent** match_list = AllocMatchList(event_list_size_); |
| if ((eventFlags & Dbg::kBreakpoint) != 0) { |
| FindMatchingEvents(EK_BREAKPOINT, &basket, match_list, &match_count); |
| } |
| if ((eventFlags & Dbg::kSingleStep) != 0) { |
| FindMatchingEvents(EK_SINGLE_STEP, &basket, match_list, &match_count); |
| } |
| if ((eventFlags & Dbg::kMethodEntry) != 0) { |
| FindMatchingEvents(EK_METHOD_ENTRY, &basket, match_list, &match_count); |
| } |
| if ((eventFlags & Dbg::kMethodExit) != 0) { |
| FindMatchingEvents(EK_METHOD_EXIT, &basket, match_list, &match_count); |
| FindMatchingEvents(EK_METHOD_EXIT_WITH_RETURN_VALUE, &basket, match_list, &match_count); |
| } |
| if (match_count != 0) { |
| VLOG(jdwp) << "EVENT: " << match_list[0]->eventKind << "(" << match_count << " total) " |
| << basket.className << "." << Dbg::GetMethodName(pLoc->method_id) |
| << StringPrintf(" thread=%#" PRIx64 " dex_pc=%#" PRIx64 ")", |
| basket.threadId, pLoc->dex_pc); |
| |
| suspend_policy = scanSuspendPolicy(match_list, match_count); |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| pReq = eventPrep(); |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, match_count); |
| |
| for (int i = 0; i < match_count; i++) { |
| expandBufAdd1(pReq, match_list[i]->eventKind); |
| expandBufAdd4BE(pReq, match_list[i]->requestId); |
| expandBufAdd8BE(pReq, basket.threadId); |
| expandBufAddLocation(pReq, *pLoc); |
| if (match_list[i]->eventKind == EK_METHOD_EXIT_WITH_RETURN_VALUE) { |
| Dbg::OutputMethodReturnValue(pLoc->method_id, returnValue, pReq); |
| } |
| } |
| } |
| |
| CleanupMatchList(match_list, match_count); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, basket.threadId); |
| return match_count != 0; |
| } |
| |
| bool JdwpState::PostFieldEvent(const JdwpLocation* pLoc, RefTypeId typeId, FieldId fieldId, |
| ObjectId thisPtr, const JValue* fieldValue, bool is_modification) { |
| ModBasket basket; |
| basket.pLoc = pLoc; |
| basket.classId = pLoc->class_id; |
| basket.thisPtr = thisPtr; |
| basket.threadId = Dbg::GetThreadSelfId(); |
| basket.className = Dbg::GetClassName(pLoc->class_id); |
| basket.fieldTypeID = typeId; |
| basket.fieldId = fieldId; |
| |
| if (InvokeInProgress()) { |
| VLOG(jdwp) << "Not posting field event during invoke"; |
| return false; |
| } |
| |
| // Get field's reference type tag. |
| JDWP::JdwpTypeTag type_tag; |
| uint32_t class_status; // unused here. |
| JdwpError error = Dbg::GetClassInfo(typeId, &type_tag, &class_status, NULL); |
| if (error != ERR_NONE) { |
| return false; |
| } |
| |
| // Get instance type tag. |
| uint8_t tag; |
| error = Dbg::GetObjectTag(thisPtr, tag); |
| if (error != ERR_NONE) { |
| return false; |
| } |
| |
| int match_count = 0; |
| ExpandBuf* pReq = NULL; |
| JdwpSuspendPolicy suspend_policy = SP_NONE; |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| JdwpEvent** match_list = AllocMatchList(event_list_size_); |
| |
| if (is_modification) { |
| FindMatchingEvents(EK_FIELD_MODIFICATION, &basket, match_list, &match_count); |
| } else { |
| FindMatchingEvents(EK_FIELD_ACCESS, &basket, match_list, &match_count); |
| } |
| if (match_count != 0) { |
| VLOG(jdwp) << "EVENT: " << match_list[0]->eventKind << "(" << match_count << " total) " |
| << basket.className << "." << Dbg::GetMethodName(pLoc->method_id) |
| << StringPrintf(" thread=%#" PRIx64 " dex_pc=%#" PRIx64 ")", |
| basket.threadId, pLoc->dex_pc); |
| |
| suspend_policy = scanSuspendPolicy(match_list, match_count); |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| pReq = eventPrep(); |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, match_count); |
| |
| for (int i = 0; i < match_count; i++) { |
| expandBufAdd1(pReq, match_list[i]->eventKind); |
| expandBufAdd4BE(pReq, match_list[i]->requestId); |
| expandBufAdd8BE(pReq, basket.threadId); |
| expandBufAddLocation(pReq, *pLoc); |
| expandBufAdd1(pReq, type_tag); |
| expandBufAddRefTypeId(pReq, typeId); |
| expandBufAddFieldId(pReq, fieldId); |
| expandBufAdd1(pReq, tag); |
| expandBufAddObjectId(pReq, thisPtr); |
| if (is_modification) { |
| Dbg::OutputFieldValue(fieldId, fieldValue, pReq); |
| } |
| } |
| } |
| |
| CleanupMatchList(match_list, match_count); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, basket.threadId); |
| return match_count != 0; |
| } |
| |
| /* |
| * A thread is starting or stopping. |
| * |
| * Valid mods: |
| * Count, ThreadOnly |
| */ |
| bool JdwpState::PostThreadChange(ObjectId threadId, bool start) { |
| CHECK_EQ(threadId, Dbg::GetThreadSelfId()); |
| |
| /* |
| * I don't think this can happen. |
| */ |
| if (InvokeInProgress()) { |
| LOG(WARNING) << "Not posting thread change during invoke"; |
| return false; |
| } |
| |
| ModBasket basket; |
| basket.threadId = threadId; |
| |
| ExpandBuf* pReq = NULL; |
| JdwpSuspendPolicy suspend_policy = SP_NONE; |
| int match_count = 0; |
| { |
| // Don't allow the list to be updated while we scan it. |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| JdwpEvent** match_list = AllocMatchList(event_list_size_); |
| |
| if (start) { |
| FindMatchingEvents(EK_THREAD_START, &basket, match_list, &match_count); |
| } else { |
| FindMatchingEvents(EK_THREAD_DEATH, &basket, match_list, &match_count); |
| } |
| |
| if (match_count != 0) { |
| VLOG(jdwp) << "EVENT: " << match_list[0]->eventKind << "(" << match_count << " total) " |
| << StringPrintf("thread=%#" PRIx64, basket.threadId) << ")"; |
| |
| suspend_policy = scanSuspendPolicy(match_list, match_count); |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| pReq = eventPrep(); |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, match_count); |
| |
| for (int i = 0; i < match_count; i++) { |
| expandBufAdd1(pReq, match_list[i]->eventKind); |
| expandBufAdd4BE(pReq, match_list[i]->requestId); |
| expandBufAdd8BE(pReq, basket.threadId); |
| } |
| } |
| |
| CleanupMatchList(match_list, match_count); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, basket.threadId); |
| |
| return match_count != 0; |
| } |
| |
| /* |
| * Send a polite "VM is dying" message to the debugger. |
| * |
| * Skips the usual "event token" stuff. |
| */ |
| bool JdwpState::PostVMDeath() { |
| VLOG(jdwp) << "EVENT: " << EK_VM_DEATH; |
| |
| ExpandBuf* pReq = eventPrep(); |
| expandBufAdd1(pReq, SP_NONE); |
| expandBufAdd4BE(pReq, 1); |
| |
| expandBufAdd1(pReq, EK_VM_DEATH); |
| expandBufAdd4BE(pReq, 0); |
| EventFinish(pReq); |
| return true; |
| } |
| |
| /* |
| * 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 JdwpState::PostException(const JdwpLocation* pThrowLoc, |
| ObjectId exceptionId, RefTypeId exceptionClassId, |
| const JdwpLocation* pCatchLoc, ObjectId thisPtr) { |
| ModBasket basket; |
| |
| basket.pLoc = pThrowLoc; |
| basket.classId = pThrowLoc->class_id; |
| basket.threadId = Dbg::GetThreadSelfId(); |
| basket.className = Dbg::GetClassName(basket.classId); |
| basket.excepClassId = exceptionClassId; |
| basket.caught = (pCatchLoc->class_id != 0); |
| basket.thisPtr = thisPtr; |
| |
| /* don't try to post an exception caused by the debugger */ |
| if (InvokeInProgress()) { |
| VLOG(jdwp) << "Not posting exception hit during invoke (" << basket.className << ")"; |
| return false; |
| } |
| |
| int match_count = 0; |
| ExpandBuf* pReq = NULL; |
| JdwpSuspendPolicy suspend_policy = SP_NONE; |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| JdwpEvent** match_list = AllocMatchList(event_list_size_); |
| FindMatchingEvents(EK_EXCEPTION, &basket, match_list, &match_count); |
| if (match_count != 0) { |
| VLOG(jdwp) << "EVENT: " << match_list[0]->eventKind << "(" << match_count << " total)" |
| << StringPrintf(" thread=%#" PRIx64, basket.threadId) |
| << StringPrintf(" exceptId=%#" PRIx64, exceptionId) |
| << " caught=" << basket.caught << ")" |
| << " throw: " << *pThrowLoc; |
| if (pCatchLoc->class_id == 0) { |
| VLOG(jdwp) << " catch: (not caught)"; |
| } else { |
| VLOG(jdwp) << " catch: " << *pCatchLoc; |
| } |
| |
| suspend_policy = scanSuspendPolicy(match_list, match_count); |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| pReq = eventPrep(); |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, match_count); |
| |
| for (int i = 0; i < match_count; i++) { |
| expandBufAdd1(pReq, match_list[i]->eventKind); |
| expandBufAdd4BE(pReq, match_list[i]->requestId); |
| expandBufAdd8BE(pReq, basket.threadId); |
| |
| expandBufAddLocation(pReq, *pThrowLoc); |
| expandBufAdd1(pReq, JT_OBJECT); |
| expandBufAdd8BE(pReq, exceptionId); |
| expandBufAddLocation(pReq, *pCatchLoc); |
| } |
| } |
| |
| CleanupMatchList(match_list, match_count); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, basket.threadId); |
| |
| return match_count != 0; |
| } |
| |
| /* |
| * Announce that a class has been loaded. |
| * |
| * Valid mods: |
| * Count, ThreadOnly, ClassOnly, ClassMatch, ClassExclude |
| */ |
| bool JdwpState::PostClassPrepare(JdwpTypeTag tag, RefTypeId refTypeId, const std::string& signature, |
| int status) { |
| ModBasket basket; |
| |
| basket.classId = refTypeId; |
| basket.threadId = Dbg::GetThreadSelfId(); |
| basket.className = Dbg::GetClassName(basket.classId); |
| |
| /* suppress class prep caused by debugger */ |
| if (InvokeInProgress()) { |
| VLOG(jdwp) << "Not posting class prep caused by invoke (" << basket.className << ")"; |
| return false; |
| } |
| |
| ExpandBuf* pReq = NULL; |
| JdwpSuspendPolicy suspend_policy = SP_NONE; |
| int match_count = 0; |
| { |
| MutexLock mu(Thread::Current(), event_list_lock_); |
| JdwpEvent** match_list = AllocMatchList(event_list_size_); |
| FindMatchingEvents(EK_CLASS_PREPARE, &basket, match_list, &match_count); |
| if (match_count != 0) { |
| VLOG(jdwp) << "EVENT: " << match_list[0]->eventKind << "(" << match_count << " total) " |
| << StringPrintf("thread=%#" PRIx64, basket.threadId) << ") " << signature; |
| |
| suspend_policy = scanSuspendPolicy(match_list, match_count); |
| VLOG(jdwp) << " suspend_policy=" << suspend_policy; |
| |
| if (basket.threadId == debug_thread_id_) { |
| /* |
| * 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. |
| */ |
| VLOG(jdwp) << " NOTE: class prepare in debugger thread!"; |
| basket.threadId = 0; |
| if (suspend_policy == SP_EVENT_THREAD) { |
| suspend_policy = SP_ALL; |
| } |
| } |
| |
| pReq = eventPrep(); |
| expandBufAdd1(pReq, suspend_policy); |
| expandBufAdd4BE(pReq, match_count); |
| |
| for (int i = 0; i < match_count; i++) { |
| expandBufAdd1(pReq, match_list[i]->eventKind); |
| expandBufAdd4BE(pReq, match_list[i]->requestId); |
| expandBufAdd8BE(pReq, basket.threadId); |
| |
| expandBufAdd1(pReq, tag); |
| expandBufAdd8BE(pReq, refTypeId); |
| expandBufAddUtf8String(pReq, signature); |
| expandBufAdd4BE(pReq, status); |
| } |
| } |
| CleanupMatchList(match_list, match_count); |
| } |
| |
| Dbg::ManageDeoptimization(); |
| |
| SendRequestAndPossiblySuspend(pReq, suspend_policy, basket.threadId); |
| |
| return match_count != 0; |
| } |
| |
| /* |
| * Send up a chunk of DDM data. |
| * |
| * While this takes the form of a JDWP "event", it doesn't interact with |
| * other debugger traffic, and can't suspend the VM, so we skip all of |
| * the fun event token gymnastics. |
| */ |
| void JdwpState::DdmSendChunkV(uint32_t type, const iovec* iov, int iov_count) { |
| uint8_t header[kJDWPHeaderLen + 8]; |
| size_t dataLen = 0; |
| |
| CHECK(iov != NULL); |
| CHECK_GT(iov_count, 0); |
| CHECK_LT(iov_count, 10); |
| |
| /* |
| * "Wrap" the contents of the iovec with a JDWP/DDMS header. We do |
| * this by creating a new copy of the vector with space for the header. |
| */ |
| std::vector<iovec> wrapiov; |
| wrapiov.push_back(iovec()); |
| for (int i = 0; i < iov_count; i++) { |
| wrapiov.push_back(iov[i]); |
| dataLen += iov[i].iov_len; |
| } |
| |
| /* form the header (JDWP plus DDMS) */ |
| Set4BE(header, sizeof(header) + dataLen); |
| Set4BE(header+4, NextRequestSerial()); |
| Set1(header+8, 0); /* flags */ |
| Set1(header+9, kJDWPDdmCmdSet); |
| Set1(header+10, kJDWPDdmCmd); |
| Set4BE(header+11, type); |
| Set4BE(header+15, dataLen); |
| |
| wrapiov[0].iov_base = header; |
| wrapiov[0].iov_len = sizeof(header); |
| |
| // Try to avoid blocking GC during a send, but only safe when not using mutexes at a lower-level |
| // than mutator for lock ordering reasons. |
| Thread* self = Thread::Current(); |
| bool safe_to_release_mutator_lock_over_send = !Locks::mutator_lock_->IsExclusiveHeld(self); |
| if (safe_to_release_mutator_lock_over_send) { |
| for (size_t i = 0; i < kMutatorLock; ++i) { |
| if (self->GetHeldMutex(static_cast<LockLevel>(i)) != NULL) { |
| safe_to_release_mutator_lock_over_send = false; |
| break; |
| } |
| } |
| } |
| if (safe_to_release_mutator_lock_over_send) { |
| // Change state to waiting to allow GC, ... while we're sending. |
| self->TransitionFromRunnableToSuspended(kWaitingForDebuggerSend); |
| SendBufferedRequest(type, wrapiov); |
| self->TransitionFromSuspendedToRunnable(); |
| } else { |
| // Send and possibly block GC... |
| SendBufferedRequest(type, wrapiov); |
| } |
| } |
| |
| } // namespace JDWP |
| |
| } // namespace art |