Moved databuffer and compresssion to vespalib

10 files changed, 3 insertions, 934 deletions

diff --git a/staging_vespalib/CMakeLists.txt b/staging_vespalib/CMakeLists.txt
index 5a169416775..d59529df828 100644
--- a/staging_vespalib/CMakeLists.txt
+++ b/staging_vespalib/CMakeLists.txt
@@ -13,7 +13,6 @@ vespa_define_module(
     src/tests/bits
     src/tests/clock
     src/tests/crc
-    src/tests/databuffer
     src/tests/directio
     src/tests/encoding/base64
     src/tests/fileheader
diff --git a/staging_vespalib/src/tests/databuffer/.gitignore b/staging_vespalib/src/tests/databuffer/.gitignore
deleted file mode 100644
index e7b0e69c372..00000000000
--- a/staging_vespalib/src/tests/databuffer/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-staging_vespalib_databuffer_test_app
diff --git a/staging_vespalib/src/tests/databuffer/CMakeLists.txt b/staging_vespalib/src/tests/databuffer/CMakeLists.txt
deleted file mode 100644
index 0c96a8cdf3e..00000000000
--- a/staging_vespalib/src/tests/databuffer/CMakeLists.txt
+++ /dev/null
@@ -1,8 +0,0 @@
-# Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-vespa_add_executable(staging_vespalib_databuffer_test_app TEST
-    SOURCES
-    databuffer_test.cpp
-    DEPENDS
-    staging_vespalib
-)
-vespa_add_test(NAME staging_vespalib_databuffer_test_app COMMAND staging_vespalib_databuffer_test_app)
diff --git a/staging_vespalib/src/tests/databuffer/databuffer_test.cpp b/staging_vespalib/src/tests/databuffer/databuffer_test.cpp
deleted file mode 100644
index f440ca1e15c..00000000000
--- a/staging_vespalib/src/tests/databuffer/databuffer_test.cpp
+++ /dev/null
@@ -1,142 +0,0 @@
-// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-
-#include <vespa/vespalib/testkit/testapp.h>
-#include <vespa/vespalib/data/databuffer.h>
-#include <iostream>
-
-using namespace vespalib;
-
-class Test : public vespalib::TestApp {
-private:
-    void testBasic();
-public:
-    int Main() override {
-        TEST_INIT("databuffer_test");
-
-        testBasic();           TEST_FLUSH();
-
-        TEST_DONE();
-    }
-};
-
-TEST_APPHOOK(Test);
-
-void
-Test::testBasic()
-{
-    DataBuffer a(50);
-    EXPECT_EQUAL(256u, a.getBufSize());
-    EXPECT_EQUAL(a.getFreeLen(), a.getBufSize());
-    a.ensureFree(1000);
-    EXPECT_EQUAL(1024u, a.getBufSize());
-    EXPECT_EQUAL(a.getFreeLen(), a.getBufSize());
-    EXPECT_EQUAL(0u, a.getDeadLen());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    EXPECT_EQUAL(a.getData(), a.getDead());
-    EXPECT_EQUAL(a.getData(), a.getFree());
-    EXPECT_EQUAL(a.getBufSize(), a.getFreeLen());
-    a.assertValid();
-
-    a.writeInt16(7);
-    EXPECT_EQUAL(0u, a.getDeadLen());
-    EXPECT_EQUAL(2u, a.getDataLen());
-    EXPECT_EQUAL(a.getBufSize()-2, a.getFreeLen());
-    EXPECT_EQUAL(a.getData(), a.getDead());
-    EXPECT_EQUAL(a.getData()+2, a.getFree());
-    a.clear();
-    EXPECT_EQUAL(0u, a.getDeadLen());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    EXPECT_EQUAL(a.getBufSize(), a.getFreeLen());
-
-    a.writeInt8(0xaau);
-    EXPECT_EQUAL(1u, a.getDataLen());    
-    EXPECT_EQUAL(0xaau, a.peekInt8(0));
-    EXPECT_EQUAL(1u, a.getDataLen());    
-    EXPECT_EQUAL(0xaau, a.readInt8());
-    EXPECT_EQUAL(0u, a.getDataLen());
-
-    a.writeInt16(0xaabbu);
-    EXPECT_EQUAL(2u, a.getDataLen());
-    EXPECT_EQUAL(0xaabbu, a.peekInt16(0));
-    EXPECT_EQUAL(2u, a.getDataLen());
-    EXPECT_EQUAL(0xaabbu, a.readInt16());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    a.writeInt16(0xaabbu);
-    EXPECT_EQUAL(2u, a.getDataLen());
-    EXPECT_EQUAL(0xbbaau, a.peekInt16Reverse(0));
-    EXPECT_EQUAL(2u, a.getDataLen());
-    EXPECT_EQUAL(0xbbaau, a.readInt16Reverse());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    
-    a.writeInt32(0xaabbccddu);
-    EXPECT_EQUAL(4u, a.getDataLen());    
-    EXPECT_EQUAL(0xaabbccddu, a.peekInt32(0));
-    EXPECT_EQUAL(4u, a.getDataLen());    
-    EXPECT_EQUAL(0xaabbccddu, a.readInt32());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    a.writeInt32(0xaabbccddu);
-    EXPECT_EQUAL(4u, a.getDataLen());    
-    EXPECT_EQUAL(0xddccbbaau, a.peekInt32Reverse(0));
-    EXPECT_EQUAL(4u, a.getDataLen());    
-    EXPECT_EQUAL(0xddccbbaau, a.readInt32Reverse());
-    EXPECT_EQUAL(0u, a.getDataLen());
-
-    a.writeInt64(0xaabbccddeeff9988ul);
-    EXPECT_EQUAL(8u, a.getDataLen());    
-    EXPECT_EQUAL(0xaabbccddeeff9988ul, a.peekInt64(0));
-    EXPECT_EQUAL(8u, a.getDataLen());    
-    EXPECT_EQUAL(0xaabbccddeeff9988ul, a.readInt64());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    a.writeInt64(0xaabbccddeeff9988ul);
-    EXPECT_EQUAL(8u, a.getDataLen());
-    EXPECT_EQUAL(0x8899ffeeddccbbaaul, a.peekInt64Reverse(0));
-    EXPECT_EQUAL(8u, a.getDataLen());    
-    EXPECT_EQUAL(0x8899ffeeddccbbaaul, a.readInt64Reverse());
-    EXPECT_EQUAL(0u, a.getDataLen());
-
-    a.writeFloat(8.9f);
-    EXPECT_EQUAL(4u, a.getDataLen());    
-    EXPECT_EQUAL(8.9f, a.readFloat());
-    EXPECT_EQUAL(0u, a.getDataLen());
-
-    a.writeDouble(8.9);
-    EXPECT_EQUAL(8u, a.getDataLen());    
-    EXPECT_EQUAL(8.9, a.readDouble());
-    EXPECT_EQUAL(0u, a.getDataLen());
-
-    const char *c = "abc";
-    char b[3];
-    a.writeBytes(c, 3);
-    EXPECT_EQUAL(3u, a.getDataLen());
-    EXPECT_EQUAL(0, memcmp(c, a.getData(), a.getDataLen()));
-    a.peekBytes(b, 3, 0);
-    EXPECT_EQUAL(3u, a.getDataLen());
-    EXPECT_EQUAL(0, memcmp(c, b, sizeof(b)));
-    a.readBytes(b, sizeof(b));
-    EXPECT_EQUAL(0u, a.getDataLen());
-    EXPECT_EQUAL(0, memcmp(c, b, sizeof(b)));
-
-    a.writeInt64(67);
-    EXPECT_EQUAL(8u, a.getDataLen());
-    EXPECT_FALSE(a.shrink(1025));
-    EXPECT_FALSE(a.shrink(7));
-    EXPECT_TRUE(a.shrink(16));
-    EXPECT_EQUAL(8u, a.getDataLen());
-    EXPECT_EQUAL(16u, a.getBufSize());
-
-    a.writeInt64(89);
-    EXPECT_EQUAL(16u, a.getDataLen());
-    EXPECT_EQUAL(16u, a.getBufSize());
-    EXPECT_EQUAL(0u, a.getDeadLen());
-    EXPECT_EQUAL(67u, a.readInt64());
-    EXPECT_EQUAL(8u, a.getDataLen());
-    EXPECT_EQUAL(8u, a.getDeadLen());
-    EXPECT_EQUAL(16u, a.getBufSize());
-    a.pack(16);
-    EXPECT_EQUAL(8u, a.getDataLen());
-    EXPECT_EQUAL(0u, a.getDeadLen());
-    EXPECT_EQUAL(256u, a.getBufSize());
-    EXPECT_EQUAL(89u, a.readInt64());
-    EXPECT_EQUAL(0u, a.getDataLen());
-    EXPECT_EQUAL(256u, a.getBufSize());
-}
diff --git a/staging_vespalib/src/tests/fileheader/fileheader_test.cpp b/staging_vespalib/src/tests/fileheader/fileheader_test.cpp
index b895b92db4c..f6f9c19b48c 100644
--- a/staging_vespalib/src/tests/fileheader/fileheader_test.cpp
+++ b/staging_vespalib/src/tests/fileheader/fileheader_test.cpp
@@ -2,6 +2,7 @@
 
 #include <vespa/vespalib/testkit/testapp.h>
 #include <vespa/vespalib/data/fileheader.h>
+#include <vespa/vespalib/data/databuffer.h>
 #include <vespa/fastos/file.h>
 #include <iostream>
 
diff --git a/staging_vespalib/src/vespa/vespalib/data/CMakeLists.txt b/staging_vespalib/src/vespa/vespalib/data/CMakeLists.txt
index 3fbece6211d..8ca70d2a63d 100644
--- a/staging_vespalib/src/vespa/vespalib/data/CMakeLists.txt
+++ b/staging_vespalib/src/vespa/vespalib/data/CMakeLists.txt
@@ -1,7 +1,6 @@
 # Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 vespa_add_library(staging_vespalib_vespalib_data OBJECT
     SOURCES
-    databuffer.cpp
     fileheader.cpp
     DEPENDS
 )
diff --git a/staging_vespalib/src/vespa/vespalib/data/databuffer.cpp b/staging_vespalib/src/vespa/vespalib/data/databuffer.cpp
deleted file mode 100644
index 529e475e987..00000000000
--- a/staging_vespalib/src/vespa/vespalib/data/databuffer.cpp
+++ /dev/null
@@ -1,171 +0,0 @@
-// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-#include "databuffer.h"
-
-namespace vespalib {
-
-namespace {
-size_t padbefore(size_t alignment, const char *buf) {
-    return (alignment - (size_t(buf) % alignment)) % alignment;
-}
-}
-
-DataBuffer::DataBuffer(size_t len, size_t alignment, const Alloc & initial)
-    : _alignment(alignment),
-      _externalBuf(NULL),
-      _bufstart(NULL),
-      _bufend(NULL),
-      _datapt(NULL),
-      _freept(NULL),
-      _buffer(initial.create(0))
-{
-    assert(_alignment > 0);
-    if (len > 0) {
-        // avoid very small buffers for performance reasons:
-        size_t bufsize = std::max(256ul, roundUp2inN(len + (_alignment - 1)));
-        Alloc newBuf(initial.create(bufsize));
-        _bufstart = static_cast<char *>(newBuf.get());
-        _buffer.swap(newBuf);
-
-        _datapt = _bufstart + padbefore(alignment, _bufstart);
-        _freept = _datapt;
-        _bufend = _bufstart + bufsize;
-        assert(_bufstart != NULL);
-    }
-}
-
-
-void
-DataBuffer::moveFreeToData(size_t len)
-{
-    assert(getFreeLen() >= len);
-    _freept += len;
-}
-
-
-void
-DataBuffer::moveDeadToData(size_t len)
-{
-    assert(getDeadLen() >= len);
-    _datapt -= len;
-    if (_bufstart != _externalBuf) {
-        assert(getDeadLen() >= padbefore(_alignment, _bufstart));  // Do not move ahead of alignment.
-    }
-}
-
-
-void
-DataBuffer::moveDataToFree(size_t len)
-{
-    assert(getDataLen() >= len);
-    _freept -= len;
-}
-
-
-bool
-DataBuffer::shrink(size_t newsize)
-{
-    if (getBufSize() <= newsize || getDataLen() > newsize) {
-        return false;
-    }
-    char *newbuf = NULL;
-    char *newdata = NULL;
-    newsize += (_alignment - 1);
-    Alloc newBuf(_buffer.create(newsize));
-    if (newsize != 0) {
-        newbuf = static_cast<char *>(newBuf.get());
-        newdata = newbuf + padbefore(_alignment, newbuf);
-        memcpy(newdata, _datapt, getDataLen());
-    }
-    _buffer.swap(newBuf);
-    _bufstart = newbuf;
-    _freept   = newdata + getDataLen();
-    _datapt   = newdata;
-    _bufend   = newbuf + newsize;
-    return true;
-}
-
-
-void
-DataBuffer::pack(size_t needbytes)
-{
-    needbytes += (_alignment - 1);
-    size_t dataLen = getDataLen();
-
-    if ((getDeadLen() + getFreeLen()) < needbytes ||
-        (getDeadLen() + getFreeLen()) * 4 < dataLen)
-    {
-        size_t bufsize = std::max(256ul, roundUp2inN(needbytes+dataLen));
-        Alloc newBuf(_buffer.create(bufsize));
-        char *newbuf = static_cast<char *>(newBuf.get());
-        char *newdata = newbuf + padbefore(_alignment, newbuf);
-        memcpy(newdata, _datapt, dataLen);
-        _bufstart = newbuf;
-        _datapt   = newdata;
-        _freept   = newdata + dataLen;
-        _bufend   = newbuf + bufsize;
-        _buffer.swap(newBuf);
-    } else {
-        char *datapt = _bufstart + padbefore(_alignment, _bufstart);
-        memmove(datapt, _datapt, dataLen);
-        _datapt = datapt;
-        _freept = _datapt + dataLen;
-    }
-}
-
-
-bool
-DataBuffer::equals(DataBuffer *other)
-{
-    if (getDataLen() != other->getDataLen())
-        return false;
-    return memcmp(getData(), other->getData(), getDataLen()) == 0;
-}
-
-
-void
-DataBuffer::hexDump()
-{
-    char *pt = _datapt;
-    printf("*** DataBuffer HexDump BEGIN ***\n");
-    uint32_t i = 0;
-    while (pt < _freept) {
-        printf("%x ", (unsigned char) *pt++);
-        if ((++i % 16) == 0)
-            printf("\n");
-    }
-    if ((i % 16) != 0)
-        printf("\n");
-    printf("*** DataBuffer HexDump END ***\n");
-}
-
-
-void
-DataBuffer::swap(DataBuffer &other)
-{
-    _buffer.swap(other._buffer);
-    std::swap(_alignment, other._alignment);
-    std::swap(_externalBuf, other._externalBuf);
-    std::swap(_bufstart, other._bufstart);
-    std::swap(_bufend, other._bufend);
-    std::swap(_datapt, other._datapt);
-    std::swap(_freept, other._freept);
-}
-
-vespalib::alloc::Alloc
-DataBuffer::stealBuffer()
-{
-    assert( ! referencesExternalData() );
-    _externalBuf = nullptr;
-    _bufstart = nullptr;
-    _bufend = nullptr;
-    _datapt = nullptr;
-    _freept = nullptr;
-    return std::move(_buffer);
-}
-
-bool
-DataBuffer::referencesExternalData() const {
-    return (_externalBuf == _bufstart) && (getBufSize() > 0);
-}
-
-} // namespace vespalib
diff --git a/staging_vespalib/src/vespa/vespalib/data/databuffer.h b/staging_vespalib/src/vespa/vespalib/data/databuffer.h
deleted file mode 100644
index f7707a3ea56..00000000000
--- a/staging_vespalib/src/vespa/vespalib/data/databuffer.h
+++ /dev/null
@@ -1,609 +0,0 @@
-// Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-#pragma once
-
-#include <cstring>
-#include <cassert>
-#include <vespa/vespalib/util/alloc.h>
-
-namespace vespalib {
-
-/**
- * This is a buffer that may hold the stream representation of
- * packets. It has helper methods in order to simplify and standardize
- * packet encoding and decoding. The default byte order for
- * reading/writing integers is internet order (big endian). The
- * methods with a 'Reverse' suffix assume that the data in the buffer
- * is stored in reverse internet order (little endian).
- *
- * A databuffer covers a continuous chunk of memory that is split into
- * 3 parts; 'dead', 'data' and 'free'. 'dead' denotes the space at the
- * beginning of the buffer that may not currently be utilized, 'data'
- * denotes the part that contains the actual data and 'free' denotes
- * the free space at the end of the buffer. Initially, the 'dead' and
- * 'data' parts are empty, and the 'free' part spans the entire
- * buffer. When writing to the buffer, bytes are transfered from the
- * 'free' part to the 'data' part of the buffer. When reading from the
- * buffer, bytes are transferred from the 'data' part to the 'dead'
- * part of the buffer. If the 'free' part of the buffer becomes empty,
- * the data will be relocated within the buffer and/or a bigger buffer
- * will be allocated.
- **/
-class DataBuffer
-{
-private:
-    using Alloc = alloc::Alloc;
-    size_t         _alignment;
-    char          *_externalBuf;
-    char          *_bufstart;
-    char          *_bufend;
-    char          *_datapt;
-    char          *_freept;
-    Alloc          _buffer;
-
-public:
-    typedef std::unique_ptr<DataBuffer> UP;
-    DataBuffer(const DataBuffer &) = delete;
-    DataBuffer &operator=(const DataBuffer &) = delete;
-
-    /**
-     * Construct a databuffer.
-     *
-     * @param len the initial size of the buffer.
-     * @param alignment required memory alignment for data start
-     **/
-    DataBuffer(size_t len = 1024, size_t alignment = 1, const Alloc & initial = Alloc::alloc(0));
-
-    /**
-     * Construct a databuffer using externally allocated memory. Note
-     * that the externally allocated memory will not be freed by the
-     * databuffer.
-     *
-     * @param buf pointer to preallocated memory
-     * @param len length of preallocated memory
-     **/
-    DataBuffer(char *buf, size_t len) :
-        _alignment(1),
-        _externalBuf(buf),
-        _bufstart(buf),
-        _bufend(buf + len),
-        _datapt(_bufstart),
-        _freept(_bufstart),
-        _buffer(Alloc::alloc(0))
-    { }
-
-    DataBuffer(const char *buf, size_t len) :
-        _alignment(1),
-        _externalBuf(const_cast<char *>(buf)),
-        _bufstart(_externalBuf),
-        _bufend(_bufstart + len),
-        _datapt(_bufstart),
-        _freept(_bufend),
-        _buffer(Alloc::alloc(0))
-    { }
-
-    /**
-     * @return a pointer to the dead part of this buffer.
-     **/
-    char     *getDead() const { return _bufstart;           }
-
-    /**
-     * @return a pointer to the data part of this buffer.
-     **/
-    char     *getData() const { return _datapt;             }
-
-    /**
-     * @return a pointer to the free part of this buffer.
-     **/
-    char     *getFree() const { return _freept;             }
-
-    /**
-     * @return the length of the dead part of this buffer.
-     **/
-    size_t    getDeadLen() const { return _datapt - _bufstart; }
-
-    /**
-     * @return the length of the data part of this buffer.
-     **/
-    size_t    getDataLen() const { return _freept - _datapt;   }
-
-    /**
-     * @return the length of the free part of this buffer.
-     **/
-    size_t    getFreeLen() const { return _bufend - _freept;   }
-
-    /**
-     * @return the length of the entire buffer.
-     **/
-    size_t    getBufSize() const { return _bufend - _bufstart; }
-
-
-    /**
-     * 'Move' bytes from the free part to the data part of this buffer.
-     * This will have the same effect as if the data already located in
-     * the free part of this buffer was written to the buffer.
-     *
-     * @param len number of bytes to 'move'.
-     **/
-    void moveFreeToData(size_t len);
-
-    /**
-     * 'Move' bytes from the data part to the dead part of this buffer.
-     * This will have the effect of discarding data without having to
-     * read it.
-     *
-     * @param len number of bytes to 'move'.
-     **/
-    void moveDataToDead(size_t len) { _datapt += len; }
-
-
-    /**
-     * 'Move' bytes from the dead part to the data part of this buffer.
-     * This may be used to undo a read operation (un-discarding
-     * data). Note that writing to the buffer may result in
-     * reorganization making the data part of the buffer disappear.
-     *
-     * @param len number of bytes to 'move'.
-     **/
-    void moveDeadToData(size_t len);
-
-    /**
-     * 'Move' bytes from the data part to the free part of this buffer.
-     * This may be used to undo a write operation; discarding the data
-     * most recently written.
-     *
-     * @param len number of bytes to 'move'.
-     **/
-    void moveDataToFree(size_t len);
-
-
-    /**
-     * Clear this buffer.
-     **/
-    void clear() { _datapt = _freept = _bufstart; }
-
-
-    /**
-     * Shrink this buffer. The given value is the new wanted size of
-     * this buffer. If the buffer is already smaller or equal in size
-     * compared to the given value, no resizing is performed and false
-     * is returned (Use the @ref ensureFree method to ensure free
-     * space). If the buffer currently contains more data than can be
-     * held in a buffer of the wanted size, no resizing is performed and
-     * false is returned.
-     *
-     * @param newsize the wanted new size of this buffer (in bytes).
-     * @return true if the buffer was shrunk, false otherwise.
-     **/
-    bool shrink(size_t newsize);
-
-    /**
-     * Reorganize this buffer such that the dead part becomes empty and
-     * the free part contains at least the given number of
-     * bytes. Allocate a bigger buffer if needed.
-     *
-     * @param needbytes required size of free part.
-     **/
-    void pack(size_t needbytes);
-
-    /**
-     * Ensure that the free part contains at least the given number of
-     * bytes. This method invokes the @ref Pack method if the free part
-     * of the buffer is too small.
-     *
-     * @param needbytes required size of free part.
-     **/
-    void ensureFree(size_t needbytes)
-    {
-        if (needbytes > getFreeLen())
-            pack(needbytes);
-    }
-
-
-    /**
-     * Write an 8-bit unsigned integer to this buffer.
-     *
-     * @param n the integer to write.
-     **/
-    void writeInt8(uint8_t n)
-    {
-        ensureFree(1);
-        *_freept++ = (char)n;
-    }
-
-    /**
-     * Write a 16-bit unsigned integer to this buffer.
-     *
-     * @param n the integer to write.
-     **/
-    void writeInt16(uint16_t n)
-    {
-        ensureFree(2);
-        _freept[1] = (char)n;
-        n >>= 8;
-        _freept[0] = (char)n;
-        _freept += 2;
-    }
-
-    /**
-     * Write a 32-bit unsigned integer to this buffer.
-     *
-     * @param n the integer to write.
-     **/
-    void writeInt32(uint32_t n)
-    {
-        ensureFree(4);
-        _freept[3] = (char)n;
-        n >>= 8;
-        _freept[2] = (char)n;
-        n >>= 8;
-        _freept[1] = (char)n;
-        n >>= 8;
-        _freept[0] = (char)n;
-        _freept += 4;
-    }
-
-    /**
-     * Write a 64-bit unsigned integer to this buffer.
-     *
-     * @param n the integer to write.
-     **/
-    void writeInt64(uint64_t n)
-    {
-        ensureFree(8);
-        _freept[7] = (char)n;
-        n >>= 8;
-        _freept[6] = (char)n;
-        n >>= 8;
-        _freept[5] = (char)n;
-        n >>= 8;
-        _freept[4] = (char)n;
-        n >>= 8;
-        _freept[3] = (char)n;
-        n >>= 8;
-        _freept[2] = (char)n;
-        n >>= 8;
-        _freept[1] = (char)n;
-        n >>= 8;
-        _freept[0] = (char)n;
-        _freept += 8;
-    }
-
-
-
-    /**
-     * Read an 8-bit unsigned integer from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint8_t readInt8()
-    {
-        return (unsigned char)(*_datapt++);
-    }
-
-    /**
-     * Read a 16-bit unsigned integer from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint16_t readInt16()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 2;
-        return ((*tmp << 8) + *(tmp + 1));
-    }
-
-    /**
-     * Read a 16-bit unsigned integer stored in reverse internet order
-     * from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint16_t readInt16Reverse()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 2;
-        return ((*(tmp + 1) << 8) + *tmp);
-    }
-
-    /**
-     * Read a 32-bit unsigned integer from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint32_t readInt32()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 4;
-        return
-            ((((((uint32_t)(*tmp << 8) + *(tmp + 1)) << 8)
-               + *(tmp + 2)) << 8) + *(tmp + 3));
-    }
-
-    /**
-     * Read a 32-bit unsigned integer stored in reverse internet order
-     * from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint32_t readInt32Reverse()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 4;
-        return
-            ((((((uint32_t)(*(tmp + 3) << 8) + *(tmp + 2)) << 8)
-               + *(tmp + 1)) << 8) + *tmp);
-    }
-
-    /**
-     * Read a 64-bit unsigned integer from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint64_t readInt64()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 8;
-        return
-            ((((((((((((((uint64_t)(*tmp << 8) + *(tmp + 1)) << 8)
-                       + *(tmp + 2)) << 8) + *(tmp + 3)) << 8)
-                   + *(tmp + 4)) << 8) + *(tmp + 5)) << 8)
-               + *(tmp + 6)) << 8) + *(tmp + 7));
-    }
-
-    /**
-     * Read a 64-bit unsigned integer stored in reverse internet order
-     * from this buffer.
-     *
-     * @return the integer that has been read.
-     **/
-    uint64_t readInt64Reverse()
-    {
-        unsigned char *tmp = (unsigned char *)(_datapt);
-        _datapt += 8;
-        return
-            ((((((((((((((uint64_t)(*(tmp + 7) << 8) + *(tmp + 6)) << 8)
-                       + *(tmp + 5)) << 8) + *(tmp + 4)) << 8)
-                   + *(tmp + 3)) << 8) + *(tmp + 2)) << 8)
-               + *(tmp + 1)) << 8) + *tmp);
-    }
-
-    float readFloat()
-    {
-        float f;
-        uint32_t i = readInt32();
-        memcpy(&f, &i, sizeof(f));
-        return f;
-    }
-
-    double readDouble()
-    {
-        double f;
-        uint64_t i = readInt64();
-        memcpy(&f, &i, sizeof(f));
-        return f;
-    }
-
-    void writeFloat(float f)
-    {
-        uint32_t i;
-        memcpy(&i, &f, sizeof(f));
-        writeInt32(i);
-    }
-
-    void writeDouble(double f)
-    {
-        uint64_t i;
-        memcpy(&i, &f, sizeof(f));
-        writeInt64(i);
-    }
-
-
-    /**
-     * Peek at an 8-bit unsigned integer in this buffer. Unlike a read
-     * operation, this will not modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint8_t peekInt8(size_t offset)
-    {
-        assert(getDataLen() >= offset + 1);
-        return (uint8_t) *(_datapt + offset);
-    }
-
-    /**
-     * Peek at a 16-bit unsigned integer in this buffer. Unlike a read
-     * operation, this will not modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint16_t peekInt16(size_t offset)
-    {
-        assert(getDataLen() >= offset + 2);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return (uint16_t) ((*tmp << 8) + *(tmp + 1));
-    }
-
-    /**
-     * Peek at a 16-bit unsigned integer stored in reverse internet
-     * order in this buffer. Unlike a read operation, this will not
-     * modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint16_t peekInt16Reverse(size_t offset)
-    {
-        assert(getDataLen() >= offset + 2);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return (uint16_t) ((*(tmp + 1) << 8) + *tmp);
-    }
-
-    /**
-     * Peek at a 32-bit unsigned integer in this buffer. Unlike a read
-     * operation, this will not modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint32_t peekInt32(size_t offset)
-    {
-        assert(getDataLen() >= offset + 4);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return
-            ((((((uint32_t)(*tmp << 8) + *(tmp + 1)) << 8)
-               + *(tmp + 2)) << 8) + *(tmp + 3));
-    }
-
-    /**
-     * Peek at a 32-bit unsigned integer stored in reverse internet
-     * order in this buffer. Unlike a read operation, this will not
-     * modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint32_t peekInt32Reverse(size_t offset)
-    {
-        assert(getDataLen() >= offset + 4);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return
-            ((((((uint32_t)(*(tmp + 3) << 8) + *(tmp + 2)) << 8)
-               + *(tmp + 1)) << 8) + *tmp);
-    }
-
-    /**
-     * Peek at a 64-bit unsigned integer in this buffer. Unlike a read
-     * operation, this will not modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint64_t peekInt64(size_t offset)
-    {
-        assert(getDataLen() >= offset + 8);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return
-            ((((((((((((((uint64_t)(*tmp << 8) + *(tmp + 1)) << 8)
-                       + *(tmp + 2)) << 8) + *(tmp + 3)) << 8)
-                   + *(tmp + 4)) << 8) + *(tmp + 5)) << 8)
-               + *(tmp + 6)) << 8) + *(tmp + 7));
-    }
-
-    /**
-     * Peek at a 64-bit unsigned integer stored in reverse internet
-     * order in this buffer. Unlike a read operation, this will not
-     * modify the buffer.
-     *
-     * @param offset offset of the integer to access.
-     * @return value of the accessed integer.
-     **/
-    uint64_t peekInt64Reverse(size_t offset)
-    {
-        assert(getDataLen() >= offset + 8);
-        unsigned char *tmp = (unsigned char *)(_datapt + offset);
-        return
-            ((((((((((((((uint64_t)(*(tmp + 7) << 8) + *(tmp + 6)) << 8)
-                       + *(tmp + 5)) << 8) + *(tmp + 4)) << 8)
-                   + *(tmp + 3)) << 8) + *(tmp + 2)) << 8)
-               + *(tmp + 1)) << 8) + *tmp);
-    }
-
-
-    /**
-     * Write bytes to this buffer.
-     *
-     * @param src source byte buffer.
-     * @param len number of bytes to write.
-     **/
-    void writeBytes(const void *src, size_t len)
-    {
-        ensureFree(len);
-        memcpy(_freept, src, len);
-        _freept += len;
-    }
-
-    /**
-     * Fill buffer with zero-bytes.
-     *
-     * @param len number of zero-bytes to write.
-     **/
-    void zeroFill(size_t len)
-    {
-        ensureFree(len);
-        memset(_freept, 0, len);
-        _freept += len;
-    }
-
-    /**
-     * Read bytes from this buffer.
-     *
-     * @param dst destination byte buffer.
-     * @param len number of bytes to read.
-     **/
-    void readBytes(void *dst, size_t len)
-    {
-        memcpy(dst, _datapt, len);
-        _datapt += len;
-    }
-
-    /**
-     * Peek at bytes in this buffer. Unlike a read operation, this will
-     * not modify the buffer.
-     *
-     * @param dst destination byte buffer.
-     * @param len number of bytes to extract.
-     * @param offset byte offset into the buffer.
-     **/
-    void peekBytes(void *dst, size_t len, size_t offset)
-    {
-        assert(_freept >= _datapt + offset + len);
-        memcpy(dst, _datapt + offset, len);
-    }
-
-    /**
-     * Check if the data stored in this buffer equals the data stored in
-     * another buffer.
-     *
-     * @return true(equal)/false(not equal)
-     * @param other the other buffer.
-     **/
-    bool equals(DataBuffer *other);
-
-    /**
-     * Print a human-readable representation of this buffer to
-     * stdout. This method may be used for debugging purposes.
-     **/
-    void hexDump();
-
-    /**
-     * Run some asserts to verify that this databuffer is in a legal
-     * state.
-     **/
-    void assertValid()
-    {
-        assert(_bufstart <= _datapt);
-        assert(_datapt <= _freept);
-        assert(_freept <= _bufend);
-    }
-
-    /**
-     * @return true if this buffer is referencing external data.
-     **/
-    bool referencesExternalData() const;
-
-    /**
-     * Swap the data stored in this buffer with the data stored in
-     * another buffer. Neither buffer may use externally allocated
-     * memory when swap is called.
-     *
-     * @param other the other buffer.
-     **/
-    void swap(DataBuffer &other);
-
-    Alloc stealBuffer();
-};
-
-} // namespace vespalib
-
diff --git a/staging_vespalib/src/vespa/vespalib/data/fileheader.cpp b/staging_vespalib/src/vespa/vespalib/data/fileheader.cpp
index 3cd8190d894..a9e131b0c63 100644
--- a/staging_vespalib/src/vespa/vespalib/data/fileheader.cpp
+++ b/staging_vespalib/src/vespa/vespalib/data/fileheader.cpp
@@ -1,6 +1,7 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #include "fileheader.h"
 #include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/vespalib/data/databuffer.h>
 #include <vespa/fastos/file.h>
 
 #include <vespa/log/log.h>
diff --git a/staging_vespalib/src/vespa/vespalib/data/fileheader.h b/staging_vespalib/src/vespa/vespalib/data/fileheader.h
index 157703ef0a8..e4449a0c36a 100644
--- a/staging_vespalib/src/vespa/vespalib/data/fileheader.h
+++ b/staging_vespalib/src/vespa/vespalib/data/fileheader.h
@@ -1,7 +1,6 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 #pragma once
 
-#include "databuffer.h"
 #include <vespa/vespalib/util/exception.h>
 #include <map>
 
@@ -9,6 +8,7 @@ class FastOS_FileInterface;
 
 namespace vespalib {
 
+class DataBuffer;
 class asciistream;
 
 /**