Delete ParcelableString, add StringParceledListSlice

Both inherit from package private BaseParceledListSlice.

This is still bad, but it's not as bad. The existing code that uses
this can just do Foo.bar().getList() now instead of having to marshal
to and from an oddball type at either end as well.

In the longer term ParceledListSlice<> should be eliminated, but it's
not clear how far into the future that is going to happen.

Test: runtest -x services/tests/servicestests/src/com/android/server/devicepolicy/DevicePolicyManagerTest.java
Test: runtest -x core/tests/coretests/src/android/content/pm/ParceledListSliceTest.java
Change-Id: Ie69b96b5215d6e04990f6d31345772cdfee21d78
This commit is contained in:
Robin Lee
2017-02-20 20:54:22 +00:00
parent c98c16ded8
commit abaa0695c5
10 changed files with 360 additions and 233 deletions

View File

@@ -0,0 +1,201 @@
/*
* Copyright (C) 2011 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.
*/
package android.content.pm;
import android.os.Binder;
import android.os.IBinder;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.RemoteException;
import android.util.Log;
import java.util.ArrayList;
import java.util.List;
/**
* Transfer a large list of Parcelable objects across an IPC. Splits into
* multiple transactions if needed.
*
* Caveat: for efficiency and security, all elements must be the same concrete type.
* In order to avoid writing the class name of each object, we must ensure that
* each object is the same type, or else unparceling then reparceling the data may yield
* a different result if the class name encoded in the Parcelable is a Base type.
* See b/17671747.
*
* @hide
*/
abstract class BaseParceledListSlice<T> implements Parcelable {
private static String TAG = "ParceledListSlice";
private static boolean DEBUG = false;
/*
* TODO get this number from somewhere else. For now set it to a quarter of
* the 1MB limit.
*/
private static final int MAX_IPC_SIZE = IBinder.MAX_IPC_SIZE;
private final List<T> mList;
public BaseParceledListSlice(List<T> list) {
mList = list;
}
@SuppressWarnings("unchecked")
BaseParceledListSlice(Parcel p, ClassLoader loader) {
final int N = p.readInt();
mList = new ArrayList<T>(N);
if (DEBUG) Log.d(TAG, "Retrieving " + N + " items");
if (N <= 0) {
return;
}
Parcelable.Creator<?> creator = readParcelableCreator(p, loader);
Class<?> listElementClass = null;
int i = 0;
while (i < N) {
if (p.readInt() == 0) {
break;
}
final T parcelable = readCreator(creator, p, loader);
if (listElementClass == null) {
listElementClass = parcelable.getClass();
} else {
verifySameType(listElementClass, parcelable.getClass());
}
mList.add(parcelable);
if (DEBUG) Log.d(TAG, "Read inline #" + i + ": " + mList.get(mList.size()-1));
i++;
}
if (i >= N) {
return;
}
final IBinder retriever = p.readStrongBinder();
while (i < N) {
if (DEBUG) Log.d(TAG, "Reading more @" + i + " of " + N + ": retriever=" + retriever);
Parcel data = Parcel.obtain();
Parcel reply = Parcel.obtain();
data.writeInt(i);
try {
retriever.transact(IBinder.FIRST_CALL_TRANSACTION, data, reply, 0);
} catch (RemoteException e) {
Log.w(TAG, "Failure retrieving array; only received " + i + " of " + N, e);
return;
}
while (i < N && reply.readInt() != 0) {
final T parcelable = reply.readCreator(creator, loader);
verifySameType(listElementClass, parcelable.getClass());
mList.add(parcelable);
if (DEBUG) Log.d(TAG, "Read extra #" + i + ": " + mList.get(mList.size()-1));
i++;
}
reply.recycle();
data.recycle();
}
}
private T readCreator(Parcelable.Creator<?> creator, Parcel p, ClassLoader loader) {
if (creator instanceof Parcelable.ClassLoaderCreator<?>) {
Parcelable.ClassLoaderCreator<?> classLoaderCreator =
(Parcelable.ClassLoaderCreator<?>) creator;
return (T) classLoaderCreator.createFromParcel(p, loader);
}
return (T) creator.createFromParcel(p);
}
private static void verifySameType(final Class<?> expected, final Class<?> actual) {
if (!actual.equals(expected)) {
throw new IllegalArgumentException("Can't unparcel type "
+ actual.getName() + " in list of type "
+ expected.getName());
}
}
public List<T> getList() {
return mList;
}
/**
* Write this to another Parcel. Note that this discards the internal Parcel
* and should not be used anymore. This is so we can pass this to a Binder
* where we won't have a chance to call recycle on this.
*/
@Override
public void writeToParcel(Parcel dest, int flags) {
final int N = mList.size();
final int callFlags = flags;
dest.writeInt(N);
if (DEBUG) Log.d(TAG, "Writing " + N + " items");
if (N > 0) {
final Class<?> listElementClass = mList.get(0).getClass();
writeParcelableCreator(mList.get(0), dest);
int i = 0;
while (i < N && dest.dataSize() < MAX_IPC_SIZE) {
dest.writeInt(1);
final T parcelable = mList.get(i);
verifySameType(listElementClass, parcelable.getClass());
writeElement(parcelable, dest, callFlags);
if (DEBUG) Log.d(TAG, "Wrote inline #" + i + ": " + mList.get(i));
i++;
}
if (i < N) {
dest.writeInt(0);
Binder retriever = new Binder() {
@Override
protected boolean onTransact(int code, Parcel data, Parcel reply, int flags)
throws RemoteException {
if (code != FIRST_CALL_TRANSACTION) {
return super.onTransact(code, data, reply, flags);
}
int i = data.readInt();
if (DEBUG) Log.d(TAG, "Writing more @" + i + " of " + N);
while (i < N && reply.dataSize() < MAX_IPC_SIZE) {
reply.writeInt(1);
final T parcelable = mList.get(i);
verifySameType(listElementClass, parcelable.getClass());
writeElement(parcelable, reply, callFlags);
if (DEBUG) Log.d(TAG, "Wrote extra #" + i + ": " + mList.get(i));
i++;
}
if (i < N) {
if (DEBUG) Log.d(TAG, "Breaking @" + i + " of " + N);
reply.writeInt(0);
}
return true;
}
};
if (DEBUG) Log.d(TAG, "Breaking @" + i + " of " + N + ": retriever=" + retriever);
dest.writeStrongBinder(retriever);
}
}
}
protected abstract void writeElement(T parcelable, Parcel reply, int callFlags);
protected abstract void writeParcelableCreator(T parcelable, Parcel dest);
protected abstract Parcelable.Creator<?> readParcelableCreator(Parcel from, ClassLoader loader);
}

View File

@@ -16,14 +16,9 @@
package android.content.pm;
import android.os.Binder;
import android.os.IBinder;
import android.os.Parcel;
import android.os.Parcelable;
import android.os.RemoteException;
import android.util.Log;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
@@ -31,171 +26,46 @@ import java.util.List;
* Transfer a large list of Parcelable objects across an IPC. Splits into
* multiple transactions if needed.
*
* Caveat: for efficiency and security, all elements must be the same concrete type.
* In order to avoid writing the class name of each object, we must ensure that
* each object is the same type, or else unparceling then reparceling the data may yield
* a different result if the class name encoded in the Parcelable is a Base type.
* See b/17671747.
* @see BaseParceledListSlice
*
* @hide
*/
public class ParceledListSlice<T extends Parcelable> implements Parcelable {
private static String TAG = "ParceledListSlice";
private static boolean DEBUG = false;
public class ParceledListSlice<T extends Parcelable> extends BaseParceledListSlice<T> {
public ParceledListSlice(List<T> list) {
super(list);
}
/*
* TODO get this number from somewhere else. For now set it to a quarter of
* the 1MB limit.
*/
private static final int MAX_IPC_SIZE = IBinder.MAX_IPC_SIZE;
private final List<T> mList;
private ParceledListSlice(Parcel in, ClassLoader loader) {
super(in, loader);
}
public static <T extends Parcelable> ParceledListSlice<T> emptyList() {
return new ParceledListSlice<T>(Collections.<T> emptyList());
}
public ParceledListSlice(List<T> list) {
mList = list;
}
@SuppressWarnings("unchecked")
private ParceledListSlice(Parcel p, ClassLoader loader) {
final int N = p.readInt();
mList = new ArrayList<T>(N);
if (DEBUG) Log.d(TAG, "Retrieving " + N + " items");
if (N <= 0) {
return;
}
Parcelable.Creator<?> creator = p.readParcelableCreator(loader);
Class<?> listElementClass = null;
int i = 0;
while (i < N) {
if (p.readInt() == 0) {
break;
}
final T parcelable = p.readCreator(creator, loader);
if (listElementClass == null) {
listElementClass = parcelable.getClass();
} else {
verifySameType(listElementClass, parcelable.getClass());
}
mList.add(parcelable);
if (DEBUG) Log.d(TAG, "Read inline #" + i + ": " + mList.get(mList.size()-1));
i++;
}
if (i >= N) {
return;
}
final IBinder retriever = p.readStrongBinder();
while (i < N) {
if (DEBUG) Log.d(TAG, "Reading more @" + i + " of " + N + ": retriever=" + retriever);
Parcel data = Parcel.obtain();
Parcel reply = Parcel.obtain();
data.writeInt(i);
try {
retriever.transact(IBinder.FIRST_CALL_TRANSACTION, data, reply, 0);
} catch (RemoteException e) {
Log.w(TAG, "Failure retrieving array; only received " + i + " of " + N, e);
return;
}
while (i < N && reply.readInt() != 0) {
final T parcelable = reply.readCreator(creator, loader);
verifySameType(listElementClass, parcelable.getClass());
mList.add(parcelable);
if (DEBUG) Log.d(TAG, "Read extra #" + i + ": " + mList.get(mList.size()-1));
i++;
}
reply.recycle();
data.recycle();
}
}
private static void verifySameType(final Class<?> expected, final Class<?> actual) {
if (!actual.equals(expected)) {
throw new IllegalArgumentException("Can't unparcel type "
+ actual.getName() + " in list of type "
+ expected.getName());
}
}
public List<T> getList() {
return mList;
}
@Override
public int describeContents() {
int contents = 0;
for (int i=0; i<mList.size(); i++) {
contents |= mList.get(i).describeContents();
final List<T> list = getList();
for (int i=0; i<list.size(); i++) {
contents |= list.get(i).describeContents();
}
return contents;
}
/**
* Write this to another Parcel. Note that this discards the internal Parcel
* and should not be used anymore. This is so we can pass this to a Binder
* where we won't have a chance to call recycle on this.
*/
@Override
public void writeToParcel(Parcel dest, int flags) {
final int N = mList.size();
final int callFlags = flags;
dest.writeInt(N);
if (DEBUG) Log.d(TAG, "Writing " + N + " items");
if (N > 0) {
final Class<?> listElementClass = mList.get(0).getClass();
dest.writeParcelableCreator(mList.get(0));
int i = 0;
while (i < N && dest.dataSize() < MAX_IPC_SIZE) {
dest.writeInt(1);
protected void writeElement(T parcelable, Parcel dest, int callFlags) {
parcelable.writeToParcel(dest, callFlags);
}
final T parcelable = mList.get(i);
verifySameType(listElementClass, parcelable.getClass());
parcelable.writeToParcel(dest, callFlags);
@Override
protected void writeParcelableCreator(T parcelable, Parcel dest) {
dest.writeParcelableCreator((Parcelable) parcelable);
}
if (DEBUG) Log.d(TAG, "Wrote inline #" + i + ": " + mList.get(i));
i++;
}
if (i < N) {
dest.writeInt(0);
Binder retriever = new Binder() {
@Override
protected boolean onTransact(int code, Parcel data, Parcel reply, int flags)
throws RemoteException {
if (code != FIRST_CALL_TRANSACTION) {
return super.onTransact(code, data, reply, flags);
}
int i = data.readInt();
if (DEBUG) Log.d(TAG, "Writing more @" + i + " of " + N);
while (i < N && reply.dataSize() < MAX_IPC_SIZE) {
reply.writeInt(1);
final T parcelable = mList.get(i);
verifySameType(listElementClass, parcelable.getClass());
parcelable.writeToParcel(reply, callFlags);
if (DEBUG) Log.d(TAG, "Wrote extra #" + i + ": " + mList.get(i));
i++;
}
if (i < N) {
if (DEBUG) Log.d(TAG, "Breaking @" + i + " of " + N);
reply.writeInt(0);
}
return true;
}
};
if (DEBUG) Log.d(TAG, "Breaking @" + i + " of " + N + ": retriever=" + retriever);
dest.writeStrongBinder(retriever);
}
}
@Override
protected Parcelable.Creator<?> readParcelableCreator(Parcel from, ClassLoader loader) {
return from.readParcelableCreator(loader);
}
@SuppressWarnings("unchecked")
@@ -210,6 +80,7 @@ public class ParceledListSlice<T extends Parcelable> implements Parcelable {
return new ParceledListSlice(in, loader);
}
@Override
public ParceledListSlice[] newArray(int size) {
return new ParceledListSlice[size];
}

View File

@@ -0,0 +1,19 @@
/*
* Copyright 2017, 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.
*/
package android.content.pm;
parcelable StringParceledListSlice;

View File

@@ -0,0 +1,83 @@
/*
* Copyright (C) 2017 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.
*/
package android.content.pm;
import android.os.Parcel;
import android.os.Parcelable;
import java.util.Collections;
import java.util.List;
/**
* Transfer a large list of Parcelable objects across an IPC. Splits into
* multiple transactions if needed.
*
* @see BaseParceledListSlice
*
* @hide
*/
public class StringParceledListSlice extends BaseParceledListSlice<String> {
public StringParceledListSlice(List<String> list) {
super(list);
}
private StringParceledListSlice(Parcel in, ClassLoader loader) {
super(in, loader);
}
public static StringParceledListSlice emptyList() {
return new StringParceledListSlice(Collections.<String> emptyList());
}
@Override
public int describeContents() {
return 0;
}
@Override
protected void writeElement(String parcelable, Parcel reply, int callFlags) {
reply.writeString(parcelable);
}
@Override
protected void writeParcelableCreator(String parcelable, Parcel dest) {
return;
}
@Override
protected Parcelable.Creator<?> readParcelableCreator(Parcel from, ClassLoader loader) {
return Parcel.STRING_CREATOR;
}
@SuppressWarnings("unchecked")
public static final Parcelable.ClassLoaderCreator<StringParceledListSlice> CREATOR =
new Parcelable.ClassLoaderCreator<StringParceledListSlice>() {
public StringParceledListSlice createFromParcel(Parcel in) {
return new StringParceledListSlice(in, null);
}
@Override
public StringParceledListSlice createFromParcel(Parcel in, ClassLoader loader) {
return new StringParceledListSlice(in, loader);
}
@Override
public StringParceledListSlice[] newArray(int size) {
return new StringParceledListSlice[size];
}
};
}

View File

@@ -1,52 +0,0 @@
/*
* Copyright 2014, 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.
*/
package com.android.internal.util;
import android.os.Parcel;
import android.os.Parcelable;
/**
* Helper class to adapt a simple String to cases where a Parcelable is expected.
* @hide
*/
public class ParcelableString implements Parcelable {
public String string;
@Override
public int describeContents() {
return 0;
}
@Override
public void writeToParcel(Parcel out, int flags) {
out.writeString(string);
}
public static final Parcelable.Creator<ParcelableString> CREATOR =
new Parcelable.Creator<ParcelableString>() {
@Override
public ParcelableString createFromParcel(Parcel in) {
ParcelableString ret = new ParcelableString();
ret.string = in.readString();
return ret;
}
@Override
public ParcelableString[] newArray(int size) {
return new ParcelableString[size];
}
};
}