rippled/modules/beast_core/streams/MemoryInputStream.cpp

//------------------------------------------------------------------------------
/*
    This file is part of Beast: https://github.com/vinniefalco/Beast
    Copyright 2013, Vinnie Falco <vinnie.falco@gmail.com>

    Portions of this file are from JUCE.
    Copyright (c) 2013 - Raw Material Software Ltd.
    Please visit http://www.juce.com

    Permission to use, copy, modify, and/or distribute this software for any
    purpose  with  or without fee is hereby granted, provided that the above
    copyright notice and this permission notice appear in all copies.

    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
//==============================================================================

MemoryInputStream::MemoryInputStream (const void* const sourceData,
                                      const size_t sourceDataSize,
                                      const bool keepInternalCopy)
    : data (sourceData),
      dataSize (sourceDataSize),
      position (0)
{
    if (keepInternalCopy)
        createInternalCopy();
}

MemoryInputStream::MemoryInputStream (const MemoryBlock& sourceData,
                                      const bool keepInternalCopy)
    : data (sourceData.getData()),
      dataSize (sourceData.getSize()),
      position (0)
{
    if (keepInternalCopy)
        createInternalCopy();
}

void MemoryInputStream::createInternalCopy()
{
    internalCopy.malloc (dataSize);
    memcpy (internalCopy, data, dataSize);
    data = internalCopy;
}

MemoryInputStream::~MemoryInputStream()
{
}

int64 MemoryInputStream::getTotalLength()
{
    return dataSize;
}

int MemoryInputStream::read (void* const buffer, const int howMany)
{
    bassert (buffer != nullptr && howMany >= 0);

    const int num = bmin (howMany, (int) (dataSize - position));
    if (num <= 0)
        return 0;

    memcpy (buffer, addBytesToPointer (data, position), (size_t) num);
    position += (unsigned int) num;
    return num;
}

bool MemoryInputStream::isExhausted()
{
    return position >= dataSize;
}

bool MemoryInputStream::setPosition (const int64 pos)
{
    position = (size_t) blimit ((int64) 0, (int64) dataSize, pos);
    return true;
}

int64 MemoryInputStream::getPosition()
{
    return position;
}

//==============================================================================

class MemoryStreamTests : public UnitTest
{
public:
    MemoryStreamTests() : UnitTest ("MemoryStream", "beast") { }

    void runTest()
    {
        beginTestCase ("Basics");
        Random r;

        int randomInt = r.nextInt();
        int64 randomInt64 = r.nextInt64();
        double randomDouble = r.nextDouble();
        String randomString (createRandomWideCharString());

        MemoryOutputStream mo;
        mo.writeInt (randomInt);
        mo.writeIntBigEndian (randomInt);
        mo.writeCompressedInt (randomInt);
        mo.writeString (randomString);
        mo.writeInt64 (randomInt64);
        mo.writeInt64BigEndian (randomInt64);
        mo.writeDouble (randomDouble);
        mo.writeDoubleBigEndian (randomDouble);

        MemoryInputStream mi (mo.getData(), mo.getDataSize(), false);
        expect (mi.readInt() == randomInt);
        expect (mi.readIntBigEndian() == randomInt);
        expect (mi.readCompressedInt() == randomInt);
        expectEquals (mi.readString(), randomString);
        expect (mi.readInt64() == randomInt64);
        expect (mi.readInt64BigEndian() == randomInt64);
        expect (mi.readDouble() == randomDouble);
        expect (mi.readDoubleBigEndian() == randomDouble);
    }

    static String createRandomWideCharString()
    {
        beast_wchar buffer [50] = { 0 };
        Random r;

        for (int i = 0; i < numElementsInArray (buffer) - 1; ++i)
        {
            if (r.nextBool())
            {
                do
                {
                    buffer[i] = (beast_wchar) (1 + r.nextInt (0x10ffff - 1));
                }
                while (! CharPointer_UTF16::canRepresent (buffer[i]));
            }
            else
                buffer[i] = (beast_wchar) (1 + r.nextInt (0xff));
        }

        return CharPointer_UTF32 (buffer);
    }
};

static MemoryStreamTests memoryStreamTests;