buffer.cpp

// This file is part of Einstein Puzzle

// Einstein Puzzle
// Copyright (C) 2003-2005  Flowix Games

// Einstein Puzzle is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.

// Einstein Puzzle 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 for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.


#include "buffer.h"

#include "exceptions.h"
#include "unicode.h"

#include <cstring>


Buffer::Buffer(int sz, int alloc)
    : size(sz), allocated(alloc), data(nullptr), currentPos(0)
{
    if (size > allocated)
        allocated = size;
    if (allocated < 1024)
        allocated = 1024;
    data = malloc(allocated);
    if (! data)
        throw Exception(L"Error allocating memory for Buffer");
}

Buffer::~Buffer()
{
    free(data);
}

void Buffer::setSize(size_t sz)
{
    if (sz > allocated) {
        int newAl = allocated + sz + 1024;
        void *d = realloc(data, newAl);
        if (! d)
            throw Exception(L"Error expanding buffer memory");
        data = d;
        allocated = newAl;
    }
    
    size = sz;
}

size_t Buffer::getSize()
{
    return size;
}

size_t Buffer::getAllocated()
{
    return allocated;
}

void* Buffer::getData()
{
    return data;
}


void Buffer::gotoPos(int offset)
{
    currentPos = offset;
}


size_t Buffer::putData(const unsigned char *d, size_t length)
{
    if (size < currentPos + length)
        setSize(currentPos + length);
    memcpy((unsigned char*)data + currentPos, d, length);
    currentPos += length;
    return length;
}


size_t Buffer::putInteger(int v)
{
    unsigned char b[4];

    for (unsigned char& i : b)
    {
        const int ib = v & 0xFF;
        v = v >> 8;
        i = ib;
    }

    return putData(b, 4);
}


size_t Buffer::putUtf8(const std::wstring &string)
{
    std::string s(toUtf8(string));
    putInteger(s.length());
    putData((const unsigned char*)s.c_str(), s.length());
    return 4 + s.length();
}


size_t Buffer::putByte(unsigned char value)
{
    if (size < (size_t)currentPos + 1)
        setSize(currentPos + 1);
    ((unsigned char*)data)[currentPos] = value;
    currentPos++;
    return 1;
}