view decoders/skeleton.c @ 562:7e08477b0fc1

MP3 decoder upgrade work. Ripped out SMPEG and mpglib support, replaced it with "mpg123.c" and libmpg123. libmpg123 is a much better version of mpglib, so it should solve all the problems about MP3's not seeking, or most modern MP3's not playing at all, etc. Since you no longer have to make a tradeoff with SMPEG for features, and SMPEG is basically rotting, I removed it from the project. There is still work to be done with libmpg123...there are MMX, 3DNow, SSE, Altivec, etc decoders which we don't have enabled at the moment, and the build system could use some work to make this compile more cleanly, etc. Still: huge win.
author Ryan C. Gordon <icculus@icculus.org>
date Fri, 30 Jan 2009 02:44:47 -0500
parents 2e8907ff98e9
children
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/*
 * SDL_sound -- An abstract sound format decoding API.
 * Copyright (C) 2001  Ryan C. Gordon.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

/*
 * FMT decoder for SDL_sound.
 *
 * This driver handles FMT audio data. Blahblahblah... The author should
 *  have done a search and replace on "fmt" and "FMT" and changed this
 *  comment. This is the default comment in the skeleton decoder file...
 *
 * None of this code, even the parts that LOOK right, have been compiled,
 *  so you cut-and-paste at your own risk.
 *
 * Please see the file LICENSE.txt in the source's root directory.
 *
 *  This file written by Ryan C. Gordon. (icculus@icculus.org)
 */

#error DO NOT COMPILE THIS.
#error  This is an example decoder skeleton.
#error  You should base your code on this file, and remove these error lines
#error  from your version.

#if HAVE_CONFIG_H
#  include <config.h>
#endif

#ifdef SOUND_SUPPORTS_FMT

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "SDL_sound.h"

#define __SDL_SOUND_INTERNAL__
#include "SDL_sound_internal.h"

static int FMT_init(void);
static void FMT_quit(void);
static int FMT_open(Sound_Sample *sample, const char *ext);
static void FMT_close(Sound_Sample *sample);
static Uint32 FMT_read(Sound_Sample *sample);
static int FMT_rewind(Sound_Sample *sample);
static int FMT_seek(Sound_Sample *sample, Uint32 ms);

static const char *extensions_fmt[] = { "FMT", NULL };
const Sound_DecoderFunctions __Sound_DecoderFunctions_FMT =
{
    {
        extensions_fmt,
        "FMT audio format description",
        "Ryan C. Gordon <icculus@icculus.org>",
        "http://www.icculus.org/SDL_sound/"
    },

    FMT_init,       /*   init() method */
    FMT_quit,       /*   quit() method */
    FMT_open,       /*   open() method */
    FMT_close,      /*  close() method */
    FMT_read,       /*   read() method */
    FMT_rewind,     /* rewind() method */
    FMT_seek        /*   seek() method */
};


static int FMT_init(void)
{
    /* do any global decoder/library initialization you need here. */

    return(1);  /* initialization successful. */
} /* FMT_init */


static void FMT_quit(void)
{
    /* do any global decoder/library cleanup you need here. */
} /* FMT_quit */


static int FMT_open(Sound_Sample *sample, const char *ext)
{
    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
    SDL_RWops *rw = internal->rw;

    if (can NOT accept the data)
        BAIL_MACRO("FMT: expected X, got Y.", 0);

    SNDDBG(("FMT: Accepting data stream.\n"));
    set up sample->actual;
    sample->flags = SOUND_SAMPLEFLAG_NONE;
    return(1); /* we'll handle this data. */
} /* FMT_open */


static void FMT_close(Sound_Sample *sample)
{
    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;
    clean up anything you put into internal->decoder_private;
} /* FMT_close */


static Uint32 FMT_read(Sound_Sample *sample)
{
    Uint32 retval;
    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

        /*
         * We don't actually do any decoding, so we read the fmt data
         *  directly into the internal buffer...
         */
    retval = SDL_RWread(internal->rw, internal->buffer,
                        1, internal->buffer_size);

    (or whatever. Do some decoding here...)

        /* Make sure the read went smoothly... */
    if (retval == 0)
        sample->flags |= SOUND_SAMPLEFLAG_EOF;

    else if (retval == -1)
        sample->flags |= SOUND_SAMPLEFLAG_ERROR;

        /* (next call this EAGAIN may turn into an EOF or error.) */
    else if (retval < internal->buffer_size)
        sample->flags |= SOUND_SAMPLEFLAG_EAGAIN;

    (or whatever. retval == number of bytes you put in internal->buffer).

    return(retval);
} /* FMT_read */


static int FMT_rewind(Sound_Sample *sample)
{
    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

        /* seek to the appropriate place... */
    BAIL_IF_MACRO(SDL_RWseek(internal->rw, 0, SEEK_SET) != 0, ERR_IO_ERROR, 0);

    (reset state as necessary.)

    return(1);  /* success. */
} /* FMT_rewind */


static int FMT_seek(Sound_Sample *sample, Uint32 ms)
{
    Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

        /* seek to the appropriate place... */
    BAIL_IF_MACRO(SDL_RWseek(internal->rw, 0, SEEK_SET) != 0, ERR_IO_ERROR, 0);

    (set state as necessary.)

    return(1);  /* success. */
} /* FMT_seek */


#endif /* SOUND_SUPPORTS_FMT */


/* end of fmt.c ... */