/*

 * Copyright 2005-2006 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/*

 * The contents of this file are subject to the Sun Public License

 * Version 1.0 (the "License"); you may not use this file except in

 * compliance with the License. A copy of the License is available at

 * http://www.sun.com/, and in the file LICENSE.html in the

 * doc directory.

 *

 * The Original Code is HAT. The Initial Developer of the

 * Original Code is Bill Foote, with contributions from others

 * at JavaSoft/Sun. Portions created by Bill Foote and others

 * at Javasoft/Sun are Copyright (C) 1997-2004. All Rights Reserved.

 *

 * In addition to the formal license, I ask that you don't

 * change the history or donations files without permission.

 *

 */

package com.sun.tools.hat.internal.parser;

import java.io.*;

import java.util.Date;

import java.util.Hashtable;

import com.sun.tools.hat.internal.model.ArrayTypeCodes;

import com.sun.tools.hat.internal.model.*;

/**

 * Object that's used to read a hprof file.

 *

 * @author      Bill Foote

 */

public class HprofReader extends Reader /* imports */ implements ArrayTypeCodes {

    final static int MAGIC_NUMBER = 0x4a415641;

    // That's "JAVA", the first part of "JAVA PROFILE ..."

    private final static String[] VERSIONS = {

            " PROFILE 1.0\0",

            " PROFILE 1.0.1\0",

            " PROFILE 1.0.2\0",

    };

    private final static int VERSION_JDK12BETA3 = 0;

    private final static int VERSION_JDK12BETA4 = 1;

    private final static int VERSION_JDK6       = 2;

    // These version numbers are indices into VERSIONS.  The instance data

    // member version is set to one of these, and it drives decisions when

    // reading the file.

    //

    // Version 1.0.1 added HPROF_GC_PRIM_ARRAY_DUMP, which requires no

    // version-sensitive parsing.

    //

    // Version 1.0.1 changed the type of a constant pool entry from a signature

    // to a typecode.

    //

    // Version 1.0.2 added HPROF_HEAP_DUMP_SEGMENT and HPROF_HEAP_DUMP_END

    // to allow a large heap to be dumped as a sequence of heap dump segments.

    //

    // The HPROF agent in J2SE 1.2 through to 5.0 generate a version 1.0.1

    // file. In Java SE 6.0 the version is either 1.0.1 or 1.0.2 depending on

    // the size of the heap (normally it will be 1.0.1 but for multi-GB

    // heaps the heap dump will not fit in a HPROF_HEAP_DUMP record so the

    // dump is generated as version 1.0.2).

    //

    // Record types:

    //

    static final int HPROF_UTF8          = 0x01;

    static final int HPROF_LOAD_CLASS    = 0x02;

    static final int HPROF_UNLOAD_CLASS  = 0x03;

    static final int HPROF_FRAME         = 0x04;

    static final int HPROF_TRACE         = 0x05;

    static final int HPROF_ALLOC_SITES   = 0x06;

    static final int HPROF_HEAP_SUMMARY  = 0x07;

    static final int HPROF_START_THREAD  = 0x0a;

    static final int HPROF_END_THREAD    = 0x0b;

    static final int HPROF_HEAP_DUMP     = 0x0c;

    static final int HPROF_CPU_SAMPLES   = 0x0d;

    static final int HPROF_CONTROL_SETTINGS = 0x0e;

    static final int HPROF_LOCKSTATS_WAIT_TIME = 0x10;

    static final int HPROF_LOCKSTATS_HOLD_TIME = 0x11;

    static final int HPROF_GC_ROOT_UNKNOWN       = 0xff;

    static final int HPROF_GC_ROOT_JNI_GLOBAL    = 0x01;

    static final int HPROF_GC_ROOT_JNI_LOCAL     = 0x02;

    static final int HPROF_GC_ROOT_JAVA_FRAME    = 0x03;

    static final int HPROF_GC_ROOT_NATIVE_STACK  = 0x04;

    static final int HPROF_GC_ROOT_STICKY_CLASS  = 0x05;

    static final int HPROF_GC_ROOT_THREAD_BLOCK  = 0x06;

    static final int HPROF_GC_ROOT_MONITOR_USED  = 0x07;

    static final int HPROF_GC_ROOT_THREAD_OBJ    = 0x08;

    static final int HPROF_GC_CLASS_DUMP         = 0x20;

    static final int HPROF_GC_INSTANCE_DUMP      = 0x21;

    static final int HPROF_GC_OBJ_ARRAY_DUMP         = 0x22;

    static final int HPROF_GC_PRIM_ARRAY_DUMP         = 0x23;

    static final int HPROF_HEAP_DUMP_SEGMENT     = 0x1c;

    static final int HPROF_HEAP_DUMP_END         = 0x2c;

    private final static int T_CLASS = 2;

    private int version;        // The version of .hprof being read

    private int debugLevel;

    private int currPos;        // Current position in the file

    private int dumpsToSkip;

    private boolean callStack;  // If true, read the call stack of objects

    private int identifierSize;         // Size, in bytes, of identifiers.

    private Hashtable<Long, String> names;

    // Hashtable<Integer, ThreadObject>, used to map the thread sequence number

    // (aka "serial number") to the thread object ID for

    // HPROF_GC_ROOT_THREAD_OBJ.  ThreadObject is a trivial inner class,

    // at the end of this file.

    private Hashtable<Integer, ThreadObject> threadObjects;

    // Hashtable<Long, String>, maps class object ID to class name

    // (with / converted to .)

    private Hashtable<Long, String> classNameFromObjectID;

    // Hashtable<Integer, Integer>, maps class serial # to class object ID

    private Hashtable<Integer, String> classNameFromSerialNo;

    // Hashtable<Long, StackFrame> maps stack frame ID to StackFrame.

    // Null if we're not tracking them.

    private Hashtable<Long, StackFrame> stackFrames;

    // Hashtable<Integer, StackTrace> maps stack frame ID to StackTrace

    // Null if we're not tracking them.

    private Hashtable<Integer, StackTrace> stackTraces;

    private Snapshot snapshot;

    public HprofReader(String fileName, PositionDataInputStream in,

                       int dumpNumber, boolean callStack, int debugLevel)

                       throws IOException {

        super(in);

        RandomAccessFile file = new RandomAccessFile(fileName, "r");

        this.snapshot = new Snapshot(MappedReadBuffer.create(file));

        this.dumpsToSkip = dumpNumber - 1;

        this.callStack = callStack;

        this.debugLevel = debugLevel;

        names = new Hashtable<Long, String>();

        threadObjects = new Hashtable<Integer, ThreadObject>(43);

        classNameFromObjectID = new Hashtable<Long, String>();

        if (callStack) {

            stackFrames = new Hashtable<Long, StackFrame>(43);

            stackTraces = new Hashtable<Integer, StackTrace>(43);

            classNameFromSerialNo = new Hashtable<Integer, String>();

        }

    }

    public Snapshot read() throws IOException {

        currPos = 4;    // 4 because of the magic number

        version = readVersionHeader();

        identifierSize = in.readInt();

        snapshot.setIdentifierSize(identifierSize);

        if (version >= VERSION_JDK12BETA4) {

            snapshot.setNewStyleArrayClass(true);

        } else {

            snapshot.setNewStyleArrayClass(false);

        }

        currPos += 4;

        if (identifierSize != 4 && identifierSize != 8) {

            throw new IOException("I'm sorry, but I can't deal with an identifier size of " + identifierSize + ".  I can only deal with 4 or 8.");

        }

        System.out.println("Dump file created " + (new Date(in.readLong())));

        currPos += 8;

        for (;;) {

            int type;

            try {

                type = in.readUnsignedByte();

            } catch (EOFException ignored) {

                break;

            }

            in.readInt();       // Timestamp of this record

            int length = in.readInt();

            if (debugLevel > 0) {

                System.out.println("Read record type " + type

                                   + ", length " + length

                                   + " at position " + toHex(currPos));

            }

            if (length < 0) {

                throw new IOException("Bad record length of " + length

                                      + " at byte " + toHex(currPos+5)

                                      + " of file.");

            }

            currPos += 9 + length;

            switch (type) {

                case HPROF_UTF8: {

                    long id = readID();

                    byte[] chars = new byte[length - identifierSize];

                    in.readFully(chars);

                    names.put(new Long(id), new String(chars));

                    break;

                }

                case HPROF_LOAD_CLASS: {

                    int serialNo = in.readInt();        // Not used

                    long classID = readID();

                    int stackTraceSerialNo = in.readInt();

                    long classNameID = readID();

                    Long classIdI = new Long(classID);

                    String nm = getNameFromID(classNameID).replace('/', '.');

                    classNameFromObjectID.put(classIdI, nm);

                    if (classNameFromSerialNo != null) {

                        classNameFromSerialNo.put(new Integer(serialNo), nm);

                    }

                    break;

                }

                case HPROF_HEAP_DUMP: {

                    if (dumpsToSkip <= 0) {

                        try {

                            readHeapDump(length, currPos);

                        } catch (EOFException exp) {

                            handleEOF(exp, snapshot);

                        }

                        if (debugLevel > 0) {

                            System.out.println("    Finished processing instances in heap dump.");

                        }

                        return snapshot;

                    } else {

                        dumpsToSkip--;

                        skipBytes(length);

                    }

                    break;

                }

                case HPROF_HEAP_DUMP_END: {

                    if (version >= VERSION_JDK6) {

                        if (dumpsToSkip <= 0) {

                            skipBytes(length);  // should be no-op

                            return snapshot;

                        } else {

                            // skip this dump (of the end record for a sequence of dump segments)

                            dumpsToSkip--;

                        }

                    } else {

                        // HPROF_HEAP_DUMP_END only recognized in >= 1.0.2

                        warn("Ignoring unrecognized record type " + type);

                    }

                    skipBytes(length);  // should be no-op

                    break;

                }

                case HPROF_HEAP_DUMP_SEGMENT: {

                    if (version >= VERSION_JDK6) {

                        if (dumpsToSkip <= 0) {

                            try {

                                // read the dump segment

                                readHeapDump(length, currPos);

                            } catch (EOFException exp) {

                                handleEOF(exp, snapshot);

                            }

                        } else {

                            // all segments comprising the heap dump will be skipped

                            skipBytes(length);

                        }

                    } else {

                        // HPROF_HEAP_DUMP_SEGMENT only recognized in >= 1.0.2

                        warn("Ignoring unrecognized record type " + type);

                        skipBytes(length);

                    }

                    break;

                }

                case HPROF_FRAME: {

                    if (stackFrames == null) {

                        skipBytes(length);

                    } else {

                        long id = readID();

                        String methodName = getNameFromID(readID());

                        String methodSig = getNameFromID(readID());

                        String sourceFile = getNameFromID(readID());

                        int classSer = in.readInt();

                        String className = classNameFromSerialNo.get(new Integer(classSer));

                        int lineNumber = in.readInt();

                        if (lineNumber < StackFrame.LINE_NUMBER_NATIVE) {

                            warn("Weird stack frame line number:  " + lineNumber);

                            lineNumber = StackFrame.LINE_NUMBER_UNKNOWN;

                        }

                        stackFrames.put(new Long(id),

                                        new StackFrame(methodName, methodSig,

                                                       className, sourceFile,

                                                       lineNumber));

                    }

                    break;

                }

                case HPROF_TRACE: {

                    if (stackTraces == null) {

                        skipBytes(length);

                    } else {

                        int serialNo = in.readInt();

                        int threadSeq = in.readInt();   // Not used

                        StackFrame[] frames = new StackFrame[in.readInt()];

                        for (int i = 0; i < frames.length; i++) {

                            long fid = readID();

                            frames[i] = stackFrames.get(new Long(fid));

                            if (frames[i] == null) {

                                throw new IOException("Stack frame " + toHex(fid) + " not found");

                            }

                        }

                        stackTraces.put(new Integer(serialNo),

                                        new StackTrace(frames));

                    }

                    break;

                }

                case HPROF_UNLOAD_CLASS:

                case HPROF_ALLOC_SITES:

                case HPROF_START_THREAD:

                case HPROF_END_THREAD:

                case HPROF_HEAP_SUMMARY:

                case HPROF_CPU_SAMPLES:

                case HPROF_CONTROL_SETTINGS:

                case HPROF_LOCKSTATS_WAIT_TIME:

                case HPROF_LOCKSTATS_HOLD_TIME:

                {

                    // Ignore these record types

                    skipBytes(length);

                    break;

                }

                default: {

                    skipBytes(length);

                    warn("Ignoring unrecognized record type " + type);

                }

            }

        }

        return snapshot;

    }

    private void skipBytes(int length) throws IOException {

        in.skipBytes(length);

    }

    private int readVersionHeader() throws IOException {

        int candidatesLeft = VERSIONS.length;

        boolean[] matched = new boolean[VERSIONS.length];

        for (int i = 0; i < candidatesLeft; i++) {

            matched[i] = true;

        }

        int pos = 0;

        while (candidatesLeft > 0) {

            char c = (char) in.readByte();

            currPos++;

            for (int i = 0; i < VERSIONS.length; i++) {

                if (matched[i]) {

                    if (c != VERSIONS[i].charAt(pos)) {   // Not matched

                        matched[i] = false;

                        --candidatesLeft;

                    } else if (pos == VERSIONS[i].length() - 1) {  // Full match

                        return i;

                    }

                }

            }

            ++pos;

        }

        throw new IOException("Version string not recognized at byte " + (pos+3));

    }

    private void readHeapDump(int bytesLeft, int posAtEnd) throws IOException {

        while (bytesLeft > 0) {

            int type = in.readUnsignedByte();

            if (debugLevel > 0) {

                System.out.println("    Read heap sub-record type " + type

                                   + " at position "

                                   + toHex(posAtEnd - bytesLeft));

            }

            bytesLeft--;

            switch(type) {

                case HPROF_GC_ROOT_UNKNOWN: {

                    long id = readID();

                    bytesLeft -= identifierSize;

                    snapshot.addRoot(new Root(id, 0, Root.UNKNOWN, ""));

                    break;

                }

                case HPROF_GC_ROOT_THREAD_OBJ: {

                    long id = readID();

                    int threadSeq = in.readInt();

                    int stackSeq = in.readInt();

                    bytesLeft -= identifierSize + 8;

                    threadObjects.put(new Integer(threadSeq),

                                      new ThreadObject(id, stackSeq));

                    break;

                }

                case HPROF_GC_ROOT_JNI_GLOBAL: {

                    long id = readID();

                    long globalRefId = readID();        // Ignored, for now

                    bytesLeft -= 2*identifierSize;

                    snapshot.addRoot(new Root(id, 0, Root.NATIVE_STATIC, ""));

                    break;

                }

                case HPROF_GC_ROOT_JNI_LOCAL: {

                    long id = readID();

                    int threadSeq = in.readInt();

                    int depth = in.readInt();

                    bytesLeft -= identifierSize + 8;

                    ThreadObject to = getThreadObjectFromSequence(threadSeq);

                    StackTrace st = getStackTraceFromSerial(to.stackSeq);

                    if (st != null) {

                        st = st.traceForDepth(depth+1);

                    }

                    snapshot.addRoot(new Root(id, to.threadId,

                                              Root.NATIVE_LOCAL, "", st));

                    break;

                }

                case HPROF_GC_ROOT_JAVA_FRAME: {

                    long id = readID();

                    int threadSeq = in.readInt();

                    int depth = in.readInt();

                    bytesLeft -= identifierSize + 8;

                    ThreadObject to = getThreadObjectFromSequence(threadSeq);

                    StackTrace st = getStackTraceFromSerial(to.stackSeq);

                    if (st != null) {

                        st = st.traceForDepth(depth+1);

                    }

                    snapshot.addRoot(new Root(id, to.threadId,

                                              Root.JAVA_LOCAL, "", st));

                    break;

                }

                case HPROF_GC_ROOT_NATIVE_STACK: {

                    long id = readID();

                    int threadSeq = in.readInt();

                    bytesLeft -= identifierSize + 4;

                    ThreadObject to = getThreadObjectFromSequence(threadSeq);

                    StackTrace st = getStackTraceFromSerial(to.stackSeq);

                    snapshot.addRoot(new Root(id, to.threadId,

                                              Root.NATIVE_STACK, "", st));

                    break;

                }

                case HPROF_GC_ROOT_STICKY_CLASS: {

                    long id = readID();

                    bytesLeft -= identifierSize;

                    snapshot.addRoot(new Root(id, 0, Root.SYSTEM_CLASS, ""));

                    break;

                }

                case HPROF_GC_ROOT_THREAD_BLOCK: {

                    long id = readID();

                    int threadSeq = in.readInt();

                    bytesLeft -= identifierSize + 4;

                    ThreadObject to = getThreadObjectFromSequence(threadSeq);

                    StackTrace st = getStackTraceFromSerial(to.stackSeq);

                    snapshot.addRoot(new Root(id, to.threadId,

                                     Root.THREAD_BLOCK, "", st));

                    break;

                }

                case HPROF_GC_ROOT_MONITOR_USED: {

                    long id = readID();

                    bytesLeft -= identifierSize;

                    snapshot.addRoot(new Root(id, 0, Root.BUSY_MONITOR, ""));

                    break;

                }

                case HPROF_GC_CLASS_DUMP: {

                    int bytesRead = readClass();

                    bytesLeft -= bytesRead;

                    break;

                }

                case HPROF_GC_INSTANCE_DUMP: {

                    int bytesRead = readInstance();

                    bytesLeft -= bytesRead;

                    break;

                }

                case HPROF_GC_OBJ_ARRAY_DUMP: {

                    int bytesRead = readArray(false);

                    bytesLeft -= bytesRead;

                    break;

                }

                case HPROF_GC_PRIM_ARRAY_DUMP: {

                    int bytesRead = readArray(true);

                    bytesLeft -= bytesRead;

                    break;

                }

                default: {

                    throw new IOException("Unrecognized heap dump sub-record type:  " + type);

                }

            }

        }

        if (bytesLeft != 0) {

            warn("Error reading heap dump or heap dump segment:  Byte count is " + bytesLeft + " instead of 0");

            skipBytes(bytesLeft);

        }

        if (debugLevel > 0) {

            System.out.println("    Finished heap sub-records.");

        }

    }

    private long readID() throws IOException {

        return (identifierSize == 4)?

            (Snapshot.SMALL_ID_MASK & (long)in.readInt()) : in.readLong();

    }

    //

    // Read a java value.  If result is non-null, it's expected to be an

    // array of one element.  We use it to fake multiple return values.

    // @returns the number of bytes read

    //