diff options
Diffstat (limited to 'eclipse/plugins/com.android.ide.eclipse.gldebugger/src/com/android/ide/eclipse/gltrace/TraceFileReader.java')
-rw-r--r-- | eclipse/plugins/com.android.ide.eclipse.gldebugger/src/com/android/ide/eclipse/gltrace/TraceFileReader.java | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/eclipse/plugins/com.android.ide.eclipse.gldebugger/src/com/android/ide/eclipse/gltrace/TraceFileReader.java b/eclipse/plugins/com.android.ide.eclipse.gldebugger/src/com/android/ide/eclipse/gltrace/TraceFileReader.java new file mode 100644 index 000000000..76b32b099 --- /dev/null +++ b/eclipse/plugins/com.android.ide.eclipse.gldebugger/src/com/android/ide/eclipse/gltrace/TraceFileReader.java @@ -0,0 +1,66 @@ +/* + * 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 com.android.ide.eclipse.gltrace; + +import com.android.ide.eclipse.gltrace.GLProtoBuf.GLMessage; +import com.google.protobuf.InvalidProtocolBufferException; + +import java.io.EOFException; +import java.io.IOException; +import java.io.RandomAccessFile; + +public class TraceFileReader { + /** Maximum size for a protocol buffer message. + * The message size is dominated by the size of the compressed framebuffer. + * Currently, we assume that the maximum is for a 1080p display. Since the buffers compress + * well, we should probably never get close to this. + */ + private static final int MAX_PROTOBUF_SIZE = 1920 * 1080 * 100; + + /** + * Obtain the next protobuf message in this file. + * @param file file to read from + * @param offset offset to start reading from + * @return protobuf message at given offset + * @throws IOException in case of file I/O errors + * @throws InvalidProtocolBufferException if protobuf is not well formed + */ + public GLMessage getMessageAtOffset(RandomAccessFile file, long offset) throws IOException { + int len; + byte[] b; + try { + if (offset != -1) { + file.seek(offset); + } + + len = file.readInt(); + if (len > MAX_PROTOBUF_SIZE) { + String msg = String.format( + "Unexpectedly large (%d bytes) protocol buffer message encountered.", + len); + throw new InvalidProtocolBufferException(msg); + } + + b = new byte[len]; + file.readFully(b); + } catch (EOFException e) { + return null; + } + + return GLMessage.parseFrom(b); + } +} |