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-rw-r--r--libs/utils/RefBase.cpp534
1 files changed, 0 insertions, 534 deletions
diff --git a/libs/utils/RefBase.cpp b/libs/utils/RefBase.cpp
deleted file mode 100644
index 0bd1af4..0000000
--- a/libs/utils/RefBase.cpp
+++ /dev/null
@@ -1,534 +0,0 @@
-/*
- * Copyright (C) 2005 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.
- */
-
-#define LOG_TAG "RefBase"
-
-#include <utils/RefBase.h>
-
-#include <utils/Atomic.h>
-#include <utils/CallStack.h>
-#include <utils/KeyedVector.h>
-#include <utils/Log.h>
-#include <utils/threads.h>
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <typeinfo>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <unistd.h>
-
-// compile with refcounting debugging enabled
-#define DEBUG_REFS 0
-#define DEBUG_REFS_ENABLED_BY_DEFAULT 1
-#define DEBUG_REFS_CALLSTACK_ENABLED 1
-
-// log all reference counting operations
-#define PRINT_REFS 0
-
-// ---------------------------------------------------------------------------
-
-namespace android {
-
-#define INITIAL_STRONG_VALUE (1<<28)
-
-// ---------------------------------------------------------------------------
-
-class RefBase::weakref_impl : public RefBase::weakref_type
-{
-public:
- volatile int32_t mStrong;
- volatile int32_t mWeak;
- RefBase* const mBase;
- volatile int32_t mFlags;
-
-
-#if !DEBUG_REFS
-
- weakref_impl(RefBase* base)
- : mStrong(INITIAL_STRONG_VALUE)
- , mWeak(0)
- , mBase(base)
- , mFlags(0)
- {
- }
-
- void addStrongRef(const void* /*id*/) { }
- void removeStrongRef(const void* /*id*/) { }
- void addWeakRef(const void* /*id*/) { }
- void removeWeakRef(const void* /*id*/) { }
- void printRefs() const { }
- void trackMe(bool, bool) { }
-
-#else
-
- weakref_impl(RefBase* base)
- : mStrong(INITIAL_STRONG_VALUE)
- , mWeak(0)
- , mBase(base)
- , mFlags(0)
- , mStrongRefs(NULL)
- , mWeakRefs(NULL)
- , mTrackEnabled(!!DEBUG_REFS_ENABLED_BY_DEFAULT)
- , mRetain(false)
- {
- //LOGI("NEW weakref_impl %p for RefBase %p", this, base);
- }
-
- ~weakref_impl()
- {
- LOG_ALWAYS_FATAL_IF(!mRetain && mStrongRefs != NULL, "Strong references remain!");
- LOG_ALWAYS_FATAL_IF(!mRetain && mWeakRefs != NULL, "Weak references remain!");
- }
-
- void addStrongRef(const void* id)
- {
- addRef(&mStrongRefs, id, mStrong);
- }
-
- void removeStrongRef(const void* id)
- {
- if (!mRetain)
- removeRef(&mStrongRefs, id);
- else
- addRef(&mStrongRefs, id, -mStrong);
- }
-
- void addWeakRef(const void* id)
- {
- addRef(&mWeakRefs, id, mWeak);
- }
-
- void removeWeakRef(const void* id)
- {
- if (!mRetain)
- removeRef(&mWeakRefs, id);
- else
- addRef(&mWeakRefs, id, -mWeak);
- }
-
- void trackMe(bool track, bool retain)
- {
- mTrackEnabled = track;
- mRetain = retain;
- }
-
- void printRefs() const
- {
- String8 text;
-
- {
- AutoMutex _l(const_cast<weakref_impl*>(this)->mMutex);
-
- char buf[128];
- sprintf(buf, "Strong references on RefBase %p (weakref_type %p):\n", mBase, this);
- text.append(buf);
- printRefsLocked(&text, mStrongRefs);
- sprintf(buf, "Weak references on RefBase %p (weakref_type %p):\n", mBase, this);
- text.append(buf);
- printRefsLocked(&text, mWeakRefs);
- }
-
- {
- char name[100];
- snprintf(name, 100, "/data/%p.stack", this);
- int rc = open(name, O_RDWR | O_CREAT | O_APPEND);
- if (rc >= 0) {
- write(rc, text.string(), text.length());
- close(rc);
- LOGD("STACK TRACE for %p saved in %s", this, name);
- }
- else LOGE("FAILED TO PRINT STACK TRACE for %p in %s: %s", this,
- name, strerror(errno));
- }
- }
-
-private:
- struct ref_entry
- {
- ref_entry* next;
- const void* id;
-#if DEBUG_REFS_CALLSTACK_ENABLED
- CallStack stack;
-#endif
- int32_t ref;
- };
-
- void addRef(ref_entry** refs, const void* id, int32_t mRef)
- {
- if (mTrackEnabled) {
- AutoMutex _l(mMutex);
- ref_entry* ref = new ref_entry;
- // Reference count at the time of the snapshot, but before the
- // update. Positive value means we increment, negative--we
- // decrement the reference count.
- ref->ref = mRef;
- ref->id = id;
-#if DEBUG_REFS_CALLSTACK_ENABLED
- ref->stack.update(2);
-#endif
-
- ref->next = *refs;
- *refs = ref;
- }
- }
-
- void removeRef(ref_entry** refs, const void* id)
- {
- if (mTrackEnabled) {
- AutoMutex _l(mMutex);
-
- ref_entry* ref = *refs;
- while (ref != NULL) {
- if (ref->id == id) {
- *refs = ref->next;
- delete ref;
- return;
- }
-
- refs = &ref->next;
- ref = *refs;
- }
-
- LOG_ALWAYS_FATAL("RefBase: removing id %p on RefBase %p (weakref_type %p) that doesn't exist!",
- id, mBase, this);
- }
- }
-
- void printRefsLocked(String8* out, const ref_entry* refs) const
- {
- char buf[128];
- while (refs) {
- char inc = refs->ref >= 0 ? '+' : '-';
- sprintf(buf, "\t%c ID %p (ref %d):\n",
- inc, refs->id, refs->ref);
- out->append(buf);
-#if DEBUG_REFS_CALLSTACK_ENABLED
- out->append(refs->stack.toString("\t\t"));
-#else
- out->append("\t\t(call stacks disabled)");
-#endif
- refs = refs->next;
- }
- }
-
- Mutex mMutex;
- ref_entry* mStrongRefs;
- ref_entry* mWeakRefs;
-
- bool mTrackEnabled;
- // Collect stack traces on addref and removeref, instead of deleting the stack references
- // on removeref that match the address ones.
- bool mRetain;
-
-#if 0
- void addRef(KeyedVector<const void*, int32_t>* refs, const void* id)
- {
- AutoMutex _l(mMutex);
- ssize_t i = refs->indexOfKey(id);
- if (i >= 0) {
- ++(refs->editValueAt(i));
- } else {
- i = refs->add(id, 1);
- }
- }
-
- void removeRef(KeyedVector<const void*, int32_t>* refs, const void* id)
- {
- AutoMutex _l(mMutex);
- ssize_t i = refs->indexOfKey(id);
- LOG_ALWAYS_FATAL_IF(i < 0, "RefBase: removing id %p that doesn't exist!", id);
- if (i >= 0) {
- int32_t val = --(refs->editValueAt(i));
- if (val == 0) {
- refs->removeItemsAt(i);
- }
- }
- }
-
- void printRefs(const KeyedVector<const void*, int32_t>& refs)
- {
- const size_t N=refs.size();
- for (size_t i=0; i<N; i++) {
- printf("\tID %p: %d remain\n", refs.keyAt(i), refs.valueAt(i));
- }
- }
-
- mutable Mutex mMutex;
- KeyedVector<const void*, int32_t> mStrongRefs;
- KeyedVector<const void*, int32_t> mWeakRefs;
-#endif
-
-#endif
-};
-
-// ---------------------------------------------------------------------------
-
-void RefBase::incStrong(const void* id) const
-{
- weakref_impl* const refs = mRefs;
- refs->addWeakRef(id);
- refs->incWeak(id);
-
- refs->addStrongRef(id);
- const int32_t c = android_atomic_inc(&refs->mStrong);
- LOG_ASSERT(c > 0, "incStrong() called on %p after last strong ref", refs);
-#if PRINT_REFS
- LOGD("incStrong of %p from %p: cnt=%d\n", this, id, c);
-#endif
- if (c != INITIAL_STRONG_VALUE) {
- return;
- }
-
- android_atomic_add(-INITIAL_STRONG_VALUE, &refs->mStrong);
- const_cast<RefBase*>(this)->onFirstRef();
-}
-
-void RefBase::decStrong(const void* id) const
-{
- weakref_impl* const refs = mRefs;
- refs->removeStrongRef(id);
- const int32_t c = android_atomic_dec(&refs->mStrong);
-#if PRINT_REFS
- LOGD("decStrong of %p from %p: cnt=%d\n", this, id, c);
-#endif
- LOG_ASSERT(c >= 1, "decStrong() called on %p too many times", refs);
- if (c == 1) {
- const_cast<RefBase*>(this)->onLastStrongRef(id);
- if ((refs->mFlags&OBJECT_LIFETIME_WEAK) != OBJECT_LIFETIME_WEAK) {
- delete this;
- }
- }
- refs->removeWeakRef(id);
- refs->decWeak(id);
-}
-
-void RefBase::forceIncStrong(const void* id) const
-{
- weakref_impl* const refs = mRefs;
- refs->addWeakRef(id);
- refs->incWeak(id);
-
- refs->addStrongRef(id);
- const int32_t c = android_atomic_inc(&refs->mStrong);
- LOG_ASSERT(c >= 0, "forceIncStrong called on %p after ref count underflow",
- refs);
-#if PRINT_REFS
- LOGD("forceIncStrong of %p from %p: cnt=%d\n", this, id, c);
-#endif
-
- switch (c) {
- case INITIAL_STRONG_VALUE:
- android_atomic_add(-INITIAL_STRONG_VALUE, &refs->mStrong);
- // fall through...
- case 0:
- const_cast<RefBase*>(this)->onFirstRef();
- }
-}
-
-int32_t RefBase::getStrongCount() const
-{
- return mRefs->mStrong;
-}
-
-
-
-RefBase* RefBase::weakref_type::refBase() const
-{
- return static_cast<const weakref_impl*>(this)->mBase;
-}
-
-void RefBase::weakref_type::incWeak(const void* id)
-{
- weakref_impl* const impl = static_cast<weakref_impl*>(this);
- impl->addWeakRef(id);
- const int32_t c = android_atomic_inc(&impl->mWeak);
- LOG_ASSERT(c >= 0, "incWeak called on %p after last weak ref", this);
-}
-
-void RefBase::weakref_type::decWeak(const void* id)
-{
- weakref_impl* const impl = static_cast<weakref_impl*>(this);
- impl->removeWeakRef(id);
- const int32_t c = android_atomic_dec(&impl->mWeak);
- LOG_ASSERT(c >= 1, "decWeak called on %p too many times", this);
- if (c != 1) return;
-
- if ((impl->mFlags&OBJECT_LIFETIME_WEAK) != OBJECT_LIFETIME_WEAK) {
- if (impl->mStrong == INITIAL_STRONG_VALUE)
- delete impl->mBase;
- else {
-// LOGV("Freeing refs %p of old RefBase %p\n", this, impl->mBase);
- delete impl;
- }
- } else {
- impl->mBase->onLastWeakRef(id);
- if ((impl->mFlags&OBJECT_LIFETIME_FOREVER) != OBJECT_LIFETIME_FOREVER) {
- delete impl->mBase;
- }
- }
-}
-
-bool RefBase::weakref_type::attemptIncStrong(const void* id)
-{
- incWeak(id);
-
- weakref_impl* const impl = static_cast<weakref_impl*>(this);
-
- int32_t curCount = impl->mStrong;
- LOG_ASSERT(curCount >= 0, "attemptIncStrong called on %p after underflow",
- this);
- while (curCount > 0 && curCount != INITIAL_STRONG_VALUE) {
- if (android_atomic_cmpxchg(curCount, curCount+1, &impl->mStrong) == 0) {
- break;
- }
- curCount = impl->mStrong;
- }
-
- if (curCount <= 0 || curCount == INITIAL_STRONG_VALUE) {
- bool allow;
- if (curCount == INITIAL_STRONG_VALUE) {
- // Attempting to acquire first strong reference... this is allowed
- // if the object does NOT have a longer lifetime (meaning the
- // implementation doesn't need to see this), or if the implementation
- // allows it to happen.
- allow = (impl->mFlags&OBJECT_LIFETIME_WEAK) != OBJECT_LIFETIME_WEAK
- || impl->mBase->onIncStrongAttempted(FIRST_INC_STRONG, id);
- } else {
- // Attempting to revive the object... this is allowed
- // if the object DOES have a longer lifetime (so we can safely
- // call the object with only a weak ref) and the implementation
- // allows it to happen.
- allow = (impl->mFlags&OBJECT_LIFETIME_WEAK) == OBJECT_LIFETIME_WEAK
- && impl->mBase->onIncStrongAttempted(FIRST_INC_STRONG, id);
- }
- if (!allow) {
- decWeak(id);
- return false;
- }
- curCount = android_atomic_inc(&impl->mStrong);
-
- // If the strong reference count has already been incremented by
- // someone else, the implementor of onIncStrongAttempted() is holding
- // an unneeded reference. So call onLastStrongRef() here to remove it.
- // (No, this is not pretty.) Note that we MUST NOT do this if we
- // are in fact acquiring the first reference.
- if (curCount > 0 && curCount < INITIAL_STRONG_VALUE) {
- impl->mBase->onLastStrongRef(id);
- }
- }
-
- impl->addWeakRef(id);
- impl->addStrongRef(id);
-
-#if PRINT_REFS
- LOGD("attemptIncStrong of %p from %p: cnt=%d\n", this, id, curCount);
-#endif
-
- if (curCount == INITIAL_STRONG_VALUE) {
- android_atomic_add(-INITIAL_STRONG_VALUE, &impl->mStrong);
- impl->mBase->onFirstRef();
- }
-
- return true;
-}
-
-bool RefBase::weakref_type::attemptIncWeak(const void* id)
-{
- weakref_impl* const impl = static_cast<weakref_impl*>(this);
-
- int32_t curCount = impl->mWeak;
- LOG_ASSERT(curCount >= 0, "attemptIncWeak called on %p after underflow",
- this);
- while (curCount > 0) {
- if (android_atomic_cmpxchg(curCount, curCount+1, &impl->mWeak) == 0) {
- break;
- }
- curCount = impl->mWeak;
- }
-
- if (curCount > 0) {
- impl->addWeakRef(id);
- }
-
- return curCount > 0;
-}
-
-int32_t RefBase::weakref_type::getWeakCount() const
-{
- return static_cast<const weakref_impl*>(this)->mWeak;
-}
-
-void RefBase::weakref_type::printRefs() const
-{
- static_cast<const weakref_impl*>(this)->printRefs();
-}
-
-void RefBase::weakref_type::trackMe(bool enable, bool retain)
-{
- static_cast<const weakref_impl*>(this)->trackMe(enable, retain);
-}
-
-RefBase::weakref_type* RefBase::createWeak(const void* id) const
-{
- mRefs->incWeak(id);
- return mRefs;
-}
-
-RefBase::weakref_type* RefBase::getWeakRefs() const
-{
- return mRefs;
-}
-
-RefBase::RefBase()
- : mRefs(new weakref_impl(this))
-{
-// LOGV("Creating refs %p with RefBase %p\n", mRefs, this);
-}
-
-RefBase::~RefBase()
-{
-// LOGV("Destroying RefBase %p (refs %p)\n", this, mRefs);
- if (mRefs->mWeak == 0) {
-// LOGV("Freeing refs %p of old RefBase %p\n", mRefs, this);
- delete mRefs;
- }
-}
-
-void RefBase::extendObjectLifetime(int32_t mode)
-{
- android_atomic_or(mode, &mRefs->mFlags);
-}
-
-void RefBase::onFirstRef()
-{
-}
-
-void RefBase::onLastStrongRef(const void* /*id*/)
-{
-}
-
-bool RefBase::onIncStrongAttempted(uint32_t flags, const void* id)
-{
- return (flags&FIRST_INC_STRONG) ? true : false;
-}
-
-void RefBase::onLastWeakRef(const void* /*id*/)
-{
-}
-
-}; // namespace android
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