usbloadergx/source/SoundOperations/SoundDecoder.cpp

/***************************************************************************
 * Copyright (C) 2010
 * by Dimok
 *
 * 3Band resampling thanks to libmad
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any
 * damages arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any
 * purpose, including commercial applications, and to alter it and
 * redistribute it freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you
 * must not claim that you wrote the original software. If you use
 * this software in a product, an acknowledgment in the product
 * documentation would be appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and
 * must not be misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source
 * distribution.
 *
 * for WiiXplorer 2010
 ***************************************************************************/
#include <gccore.h>
#include <malloc.h>
#include <string.h>
#include <unistd.h>
#include "SoundDecoder.hpp"
#include "main.h"

SoundDecoder::SoundDecoder()
{
    file_fd = NULL;
    Init();
}

SoundDecoder::SoundDecoder(const char * filepath)
{
    file_fd = new CFile(filepath, "rb");
    Init();
}

SoundDecoder::SoundDecoder(const u8 * buffer, int size)
{
    file_fd = new CFile(buffer, size);
    Init();
}

SoundDecoder::~SoundDecoder()
{
    ExitRequested = true;
    while(Decoding)
        usleep(100);

    if(file_fd)
        delete file_fd;
    file_fd = NULL;
}

void SoundDecoder::Init()
{
    SoundType = SOUND_RAW;
    SoundBlocks = 8;
    SoundBlockSize = 8192;
    CurPos = 0;
    Loop = false;
    EndOfFile = false;
    Decoding = false;
    ExitRequested = false;
    SoundBuffer.SetBufferBlockSize(SoundBlockSize);
    SoundBuffer.Resize(SoundBlocks);
}

int SoundDecoder::Rewind()
{
    CurPos = 0;
    EndOfFile = false;
    file_fd->rewind();

    return 0;
}

int SoundDecoder::Read(u8 * buffer, int buffer_size, int pos)
{
    int ret = file_fd->read(buffer, buffer_size);
    CurPos += ret;

    return ret;
}

void SoundDecoder::Decode()
{
    if(!file_fd || ExitRequested || EndOfFile)
        return;

    u16 newWhich = SoundBuffer.Which();
    u16 i = 0;
    for (i = 0; i < SoundBuffer.Size()-2; i++)
    {
        if(!SoundBuffer.IsBufferReady(newWhich))
            break;

        newWhich = (newWhich+1) % SoundBuffer.Size();
    }

    if(i == SoundBuffer.Size()-2)
        return;

    Decoding = true;

    int done  = 0;
    u8 * write_buf = SoundBuffer.GetBuffer(newWhich);
    if(!write_buf)
    {
        ExitRequested = true;
        Decoding = false;
        return;
    }

    while(done < SoundBlockSize)
    {
        int ret = Read(&write_buf[done], SoundBlockSize-done, Tell());

        if(ret <= 0)
        {
            if(Loop)
            {
                Rewind();
                continue;
            }
            else
            {
                EndOfFile = true;
                break;
            }
        }

        done += ret;
    }

    if(done > 0)
    {
        SoundBuffer.SetBufferSize(newWhich, done);
        SoundBuffer.SetBufferReady(newWhich, true);
    }

	if(!SoundBuffer.IsBufferReady((newWhich+1) % SoundBuffer.Size()))
        Decode();

    Decoding = false;
}