/*

SDL_mixer: An audio mixer library based on the SDL library

Copyright (C) 1997-2017 Sam Lantinga <slouken@libsdl.org>

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.

*/

#ifdef MUSIC_MP3_MPG123

#include <stdio.h> // For SEEK_SET

#include "SDL_loadso.h"

#include "music_mpg123.h"

#include <mpg123.h>

typedef struct {

int loaded;

void *handle;

int (*mpg123_close)(mpg123_handle *mh);

void (*mpg123_delete)(mpg123_handle *mh);

void (*mpg123_exit)(void);

int (*mpg123_format)( mpg123_handle *mh, long rate, int channels, int encodings );

int (*mpg123_format_none)(mpg123_handle *mh);

int (*mpg123_getformat)( mpg123_handle *mh, long *rate, int *channels, int *encoding );

int (*mpg123_init)(void);

mpg123_handle *(*mpg123_new)(const char* decoder, int *error);

int (*mpg123_open_handle)(mpg123_handle *mh, void *iohandle);

const char* (*mpg123_plain_strerror)(int errcode);

int (*mpg123_read)(mpg123_handle *mh, unsigned char *outmemory, size_t outmemsize, size_t *done );

int (*mpg123_replace_reader_handle)( mpg123_handle *mh, ssize_t (*r_read) (void *, void *, size_t), off_t (*r_lseek)(void *, off_t, int), void (*cleanup)(void*) );

off_t (*mpg123_seek)( mpg123_handle *mh, off_t sampleoff, int whence );

const char* (*mpg123_strerror)(mpg123_handle *mh);

} mpg123_loader;

static mpg123_loader mpg123 = {

0, NULL

};

#ifdef MPG123_DYNAMIC

#define FUNCTION_LOADER(FUNC, SIG) \

mpg123.FUNC = (SIG) SDL_LoadFunction(mpg123.handle, #FUNC); \

if (mpg123.FUNC == NULL) { SDL_UnloadObject(mpg123.handle); return -1; }

#else

#define FUNCTION_LOADER(FUNC, SIG) \

mpg123.FUNC = FUNC;

#endif

{

if (mpg123.loaded == 0) {

#ifdef MPG123_DYNAMIC

mpg123.handle = SDL_LoadObject(MPG123_DYNAMIC);

if (mpg123.handle == NULL) {

return -1;

}

#elif defined(__MACOSX__)

extern int mpg123_init(void) __attribute__((weak_import));

if (mpg123_init == NULL)

{

/* Missing weakly linked framework */

Mix_SetError("Missing mpg123.framework");

return -1;

}

#endif

FUNCTION_LOADER(mpg123_close, int (*)(mpg123_handle *mh))

FUNCTION_LOADER(mpg123_delete, void (*)(mpg123_handle *mh))

FUNCTION_LOADER(mpg123_exit, void (*)(void))

FUNCTION_LOADER(mpg123_format, int (*)( mpg123_handle *mh, long rate, int channels, int encodings ))

FUNCTION_LOADER(mpg123_format_none, int (*)(mpg123_handle *mh))

FUNCTION_LOADER(mpg123_getformat, int (*)( mpg123_handle *mh, long *rate, int *channels, int *encoding ))

FUNCTION_LOADER(mpg123_init, int (*)(void))

FUNCTION_LOADER(mpg123_new, mpg123_handle *(*)(const char* decoder, int *error))

FUNCTION_LOADER(mpg123_open_handle, int (*)(mpg123_handle *mh, void *iohandle))

FUNCTION_LOADER(mpg123_plain_strerror, const char* (*)(int errcode))

FUNCTION_LOADER(mpg123_read, int (*)(mpg123_handle *mh, unsigned char *outmemory, size_t outmemsize, size_t *done ))

FUNCTION_LOADER(mpg123_replace_reader_handle, int (*)( mpg123_handle *mh, ssize_t (*r_read) (void *, void *, size_t), off_t (*r_lseek)(void *, off_t, int), void (*cleanup)(void*) ))

FUNCTION_LOADER(mpg123_seek, off_t (*)( mpg123_handle *mh, off_t sampleoff, int whence ))

FUNCTION_LOADER(mpg123_strerror, const char* (*)(mpg123_handle *mh))

}

++mpg123.loaded;

return 0;

}

{

if (mpg123.loaded == 0) {

return;

}

if (mpg123.loaded == 1) {

#ifdef MPG123_DYNAMIC

SDL_UnloadObject(mpg123.handle);

#endif

}

--mpg123.loaded;

}

typedef struct

{

SDL_RWops* src;

int freesrc;

int volume;

mpg123_handle* handle;

SDL_AudioStream *stream;

unsigned char *buffer;

size_t buffer_size;

} MPG123_Music;

static int MPG123_Seek(void *context, double secs);

static void MPG123_Delete(void *context);

{

switch (fmt)

{

case MPG123_ENC_SIGNED_8: return AUDIO_S8;

case MPG123_ENC_UNSIGNED_8: return AUDIO_U8;

case MPG123_ENC_SIGNED_16: return AUDIO_S16SYS;

case MPG123_ENC_UNSIGNED_16: return AUDIO_U16SYS;

case MPG123_ENC_SIGNED_32: return AUDIO_S32SYS;

case MPG123_ENC_FLOAT_32: return AUDIO_F32SYS;

default: return -1;

}

}

/*

static const char *mpg123_format_str(int fmt)

{

switch (fmt)

{

#define f(x) case x: return #x;

f(MPG123_ENC_UNSIGNED_8)

f(MPG123_ENC_UNSIGNED_16)

f(MPG123_ENC_SIGNED_8)

f(MPG123_ENC_SIGNED_16)

f(MPG123_ENC_SIGNED_32)

#undef f

}

return "unknown";

}

{

char const* err = "unknown error";

}

return err;

}

/* we're gonna override mpg123's I/O with these wrappers for RWops */

static ssize_t rwops_read(void* p, void* dst, size_t n)

{

return (ssize_t)SDL_RWread((SDL_RWops*)p, dst, 1, n);

}

static off_t rwops_seek(void* p, off_t offset, int whence)

{

return (off_t)SDL_RWseek((SDL_RWops*)p, (Sint64)offset, whence);

}

static void rwops_cleanup(void* p)

{

(void)p;

/* do nothing, we will free the file later */

}

static int MPG123_Open(const SDL_AudioSpec *spec)

{

Mix_SetError("mpg123_init() failed");

return -1;

}

return 0;

}

static void *MPG123_CreateFromRW(SDL_RWops *src, int freesrc)

const long *rates;

size_t i, num_rates;

music = (MPG123_Music*)SDL_calloc(1, sizeof(*music));

if (!music) {

return NULL;

}

music->src = src;

music->volume = MIX_MAX_VOLUME;

/* Just assume 16-bit 2 channel audio for now */

music->buffer_size = music_spec.samples * sizeof(Sint16) * 2;

music->buffer = (unsigned char *)SDL_malloc(music->buffer_size);

if (!music->buffer) {

MPG123_Delete(music);

SDL_OutOfMemory();

return NULL;

}

MPG123_Delete(music);

Mix_SetError("mpg123_new failed");

return NULL;

}

MPG123_Delete(music);

Mix_SetError("mpg123_replace_reader_handle: %s", mpg_err(music->handle, result));

return NULL;

}

MPG123_Delete(music);

Mix_SetError("mpg123_format_none: %s", mpg_err(music->handle, result));

return NULL;

}

mpg123.mpg123_rates(&rates, &num_rates);

for (i = 0; i < num_rates; ++i) {

const int channels = (MPG123_MONO|MPG123_STEREO);

const int formats = (MPG123_ENC_SIGNED_8 |

MPG123_ENC_UNSIGNED_8 |

MPG123_ENC_SIGNED_16 |

MPG123_ENC_UNSIGNED_16 |

MPG123_ENC_SIGNED_32 |

MPG123_ENC_FLOAT_32);

mpg123.mpg123_format(music->handle, rates[i], channels, formats);

}

MPG123_Delete(music);

Mix_SetError("mpg123_open_handle: %s", mpg_err(music->handle, result));

return NULL;

}

music->freesrc = freesrc;

return music;

}

MPG123_Music *music = (MPG123_Music *)context;

music->volume = volume;

}

MPG123_Music *music = (MPG123_Music *)context;

music->play_count = play_count;

return MPG123_Seek(music, 0.0);

}

/* read some mp3 stream data and convert it for output */

static int MPG123_GetSome(void *context, void *data, int bytes, SDL_bool *done)

MPG123_Music *music = (MPG123_Music *)context;

int filled, result;

size_t amount;

if (music->stream) {

filled = SDL_AudioStreamGet(music->stream, data, bytes);

if (filled != 0) {

return filled;

}

}

if (!music->play_count) {

/* All done */

*done = SDL_TRUE;

return 0;

}

result = mpg123.mpg123_read(music->handle, music->buffer, music->buffer_size, &amount);

switch (result) {

case MPG123_OK:

if (SDL_AudioStreamPut(music->stream, music->buffer, (int)amount) < 0) {

return -1;

case MPG123_NEW_FORMAT:

result = mpg123.mpg123_getformat(music->handle, &rate, &channels, &encoding);

if (result != MPG123_OK) {

Mix_SetError("mpg123_getformat: %s", mpg_err(music->handle, result));

return -1;

format = mpg123_format_to_sdl(encoding);

SDL_assert(format != -1);

music->stream = SDL_NewAudioStream(format, channels, (int)rate,

music_spec.format, music_spec.channels, music_spec.freq);

if (!music->stream) {

return -1;

break;

case MPG123_DONE:

if (music->play_count == 1) {

music->play_count = 0;

SDL_AudioStreamFlush(music->stream);

} else {

int play_count = -1;

if (music->play_count > 0) {

play_count = (music->play_count - 1);

}

if (MPG123_Play(music, play_count) < 0) {

return -1;

}

break;

default:

Mix_SetError("mpg123_read: %s", mpg_err(music->handle, result));

return -1;

return 0;

}

static int MPG123_GetAudio(void *context, void *data, int bytes)

{

MPG123_Music *music = (MPG123_Music *)context;

return music_pcm_getaudio(context, data, bytes, music->volume, MPG123_GetSome);

}

MPG123_Music *music = (MPG123_Music *)context;

off_t offset = (off_t)(music_spec.freq * secs);

if ((offset = mpg123.mpg123_seek(music->handle, offset, SEEK_SET)) < 0) {

return Mix_SetError("mpg123_seek: %s", mpg_err(music->handle, (int)-offset));

}

static void MPG123_Delete(void *context)

{

if (music->handle) {

mpg123.mpg123_close(music->handle);

mpg123.mpg123_delete(music->handle);

if (music->stream) {

SDL_FreeAudioStream(music->stream);

if (music->buffer) {

SDL_free(music->buffer);

}

if (music->freesrc) {

SDL_RWclose(music->src);

}

SDL_free(music);

}

static void MPG123_Close(void)

{

}

Mix_MusicInterface Mix_MusicInterface_MPG123 =

{

"MPG123",

MIX_MUSIC_MPG123,

MUS_MP3,

SDL_FALSE,

SDL_FALSE,

MPG123_Open,

MPG123_CreateFromRW,

NULL, /* CreateFromFile */

MPG123_SetVolume,

MPG123_Play,

MPG123_GetAudio,

MPG123_Seek,

NULL, /* Pause */

NULL, /* Resume */

MPG123_Delete,

MPG123_Close,

};

#endif /* MUSIC_MP3_MPG123 */

/* vi: set ts=4 sw=4 expandtab: */