/*
* 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.
*/
#include <binder/Binder.h>
#include <atomic>
#include <utils/misc.h>
#include <binder/BpBinder.h>
#include <binder/IInterface.h>
#include <binder/IResultReceiver.h>
#include <binder/IShellCallback.h>
#include <binder/Parcel.h>
#include <stdio.h>
namespace android {
// ---------------------------------------------------------------------------
IBinder::IBinder()
: RefBase()
{
}
IBinder::~IBinder()
{
}
// ---------------------------------------------------------------------------
sp<IInterface> IBinder::queryLocalInterface(const String16& /*descriptor*/)
{
return nullptr;
}
BBinder* IBinder::localBinder()
{
return nullptr;
}
BpBinder* IBinder::remoteBinder()
{
return nullptr;
}
bool IBinder::checkSubclass(const void* /*subclassID*/) const
{
return false;
}
status_t IBinder::shellCommand(const sp<IBinder>& target, int in, int out, int err,
Vector<String16>& args, const sp<IShellCallback>& callback,
const sp<IResultReceiver>& resultReceiver)
{
Parcel send;
Parcel reply;
send.writeFileDescriptor(in);
send.writeFileDescriptor(out);
send.writeFileDescriptor(err);
const size_t numArgs = args.size();
send.writeInt32(numArgs);
for (size_t i = 0; i < numArgs; i++) {
send.writeString16(args[i]);
}
send.writeStrongBinder(callback != nullptr ? IInterface::asBinder(callback) : nullptr);
send.writeStrongBinder(resultReceiver != nullptr ? IInterface::asBinder(resultReceiver) : nullptr);
return target->transact(SHELL_COMMAND_TRANSACTION, send, &reply);
}
// ---------------------------------------------------------------------------
class BBinder::Extras
{
public:
// unlocked objects
bool mRequestingSid = false;
// for below objects
Mutex mLock;
BpBinder::ObjectManager mObjects;
};
// ---------------------------------------------------------------------------
BBinder::BBinder() : mExtras(nullptr)
{
}
bool BBinder::isBinderAlive() const
{
return true;
}
status_t BBinder::pingBinder()
{
return NO_ERROR;
}
const String16& BBinder::getInterfaceDescriptor() const
{
// This is a local static rather than a global static,
// to avoid static initializer ordering issues.
static String16 sEmptyDescriptor;
ALOGW("reached BBinder::getInterfaceDescriptor (this=%p)", this);
return sEmptyDescriptor;
}
// NOLINTNEXTLINE(google-default-arguments)
status_t BBinder::transact(
uint32_t code, const Parcel& data, Parcel* reply, uint32_t flags)
{
data.setDataPosition(0);
status_t err = NO_ERROR;
switch (code) {
case PING_TRANSACTION:
reply->writeInt32(pingBinder());
break;
default:
err = onTransact(code, data, reply, flags);
break;
}
if (reply != nullptr) {
reply->setDataPosition(0);
}
return err;
}
// NOLINTNEXTLINE(google-default-arguments)
status_t BBinder::linkToDeath(
const sp<DeathRecipient>& /*recipient*/, void* /*cookie*/,
uint32_t /*flags*/)
{
return INVALID_OPERATION;
}
// NOLINTNEXTLINE(google-default-arguments)
status_t BBinder::unlinkToDeath(
const wp<DeathRecipient>& /*recipient*/, void* /*cookie*/,
uint32_t /*flags*/, wp<DeathRecipient>* /*outRecipient*/)
{
return INVALID_OPERATION;
}
status_t BBinder::dump(int /*fd*/, const Vector<String16>& /*args*/)
{
return NO_ERROR;
}
void BBinder::attachObject(
const void* objectID, void* object, void* cleanupCookie,
object_cleanup_func func)
{
Extras* e = getOrCreateExtras();
if (!e) return; // out of memory
AutoMutex _l(e->mLock);
e->mObjects.attach(objectID, object, cleanupCookie, func);
}
void* BBinder::findObject(const void* objectID) const
{
Extras* e = mExtras.load(std::memory_order_acquire);
if (!e) return nullptr;
AutoMutex _l(e->mLock);
return e->mObjects.find(objectID);
}
void BBinder::detachObject(const void* objectID)
{
Extras* e = mExtras.load(std::memory_order_acquire);
if (!e) return;
AutoMutex _l(e->mLock);
e->mObjects.detach(objectID);
}
BBinder* BBinder::localBinder()
{
return this;
}
bool BBinder::isRequestingSid()
{
Extras* e = mExtras.load(std::memory_order_acquire);
return e && e->mRequestingSid;
}
void BBinder::setRequestingSid(bool requestingSid)
{
Extras* e = mExtras.load(std::memory_order_acquire);
if (!e) {
// default is false. Most things don't need sids, so avoiding allocations when possible.
if (!requestingSid) {
return;
}
e = getOrCreateExtras();
if (!e) return; // out of memory
}
e->mRequestingSid = requestingSid;
}
BBinder::~BBinder()
{
Extras* e = mExtras.load(std::memory_order_relaxed);
if (e) delete e;
}
// NOLINTNEXTLINE(google-default-arguments)
status_t BBinder::onTransact(
uint32_t code, const Parcel& data, Parcel* reply, uint32_t /*flags*/)
{
switch (code) {
case INTERFACE_TRANSACTION:
reply->writeString16(getInterfaceDescriptor());
return NO_ERROR;
case DUMP_TRANSACTION: {
int fd = data.readFileDescriptor();
int argc = data.readInt32();
Vector<String16> args;
for (int i = 0; i < argc && data.dataAvail() > 0; i++) {
args.add(data.readString16());
}
return dump(fd, args);
}
case SHELL_COMMAND_TRANSACTION: {
int in = data.readFileDescriptor();
int out = data.readFileDescriptor();
int err = data.readFileDescriptor();
int argc = data.readInt32();
Vector<String16> args;
for (int i = 0; i < argc && data.dataAvail() > 0; i++) {
args.add(data.readString16());
}
sp<IShellCallback> shellCallback = IShellCallback::asInterface(
data.readStrongBinder());
sp<IResultReceiver> resultReceiver = IResultReceiver::asInterface(
data.readStrongBinder());
// XXX can't add virtuals until binaries are updated.
//return shellCommand(in, out, err, args, resultReceiver);
(void)in;
(void)out;
(void)err;
if (resultReceiver != nullptr) {
resultReceiver->send(INVALID_OPERATION);
}
return NO_ERROR;
}
case SYSPROPS_TRANSACTION: {
report_sysprop_change();
return NO_ERROR;
}
default:
return UNKNOWN_TRANSACTION;
}
}
BBinder::Extras* BBinder::getOrCreateExtras()
{
Extras* e = mExtras.load(std::memory_order_acquire);
if (!e) {
e = new Extras;
Extras* expected = nullptr;
if (!mExtras.compare_exchange_strong(expected, e,
std::memory_order_release,
std::memory_order_acquire)) {
delete e;
e = expected; // Filled in by CAS
}
if (e == nullptr) return nullptr; // out of memory
}
return e;
}
// ---------------------------------------------------------------------------
enum {
// This is used to transfer ownership of the remote binder from
// the BpRefBase object holding it (when it is constructed), to the
// owner of the BpRefBase object when it first acquires that BpRefBase.
kRemoteAcquired = 0x00000001
};
BpRefBase::BpRefBase(const sp<IBinder>& o)
: mRemote(o.get()), mRefs(nullptr), mState(0)
{
extendObjectLifetime(OBJECT_LIFETIME_WEAK);
if (mRemote) {
mRemote->incStrong(this); // Removed on first IncStrong().
mRefs = mRemote->createWeak(this); // Held for our entire lifetime.
}
}
BpRefBase::~BpRefBase()
{
if (mRemote) {
if (!(mState.load(std::memory_order_relaxed)&kRemoteAcquired)) {
mRemote->decStrong(this);
}
mRefs->decWeak(this);
}
}
void BpRefBase::onFirstRef()
{
mState.fetch_or(kRemoteAcquired, std::memory_order_relaxed);
}
void BpRefBase::onLastStrongRef(const void* /*id*/)
{
if (mRemote) {
mRemote->decStrong(this);
}
}
bool BpRefBase::onIncStrongAttempted(uint32_t /*flags*/, const void* /*id*/)
{
return mRemote ? mRefs->attemptIncStrong(this) : false;
}
// ---------------------------------------------------------------------------
}; // namespace android