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#include "audio/nebu_SourceMusic.h"
#include <string.h>
#include <stdlib.h>
namespace Sound {
SourceMusic::SourceMusic(System *system) {
_system = system;
_sample = NULL;
_sample_buffersize = 8192;
_buffersize = 20 * _sample_buffersize;
_buffer = (Uint8*) malloc( _buffersize );
memset(_buffer, 0, _buffersize);
_decoded = 0;
_read = 0;
_filename = NULL;
_rwops = NULL;
}
SourceMusic::~SourceMusic() {
// fprintf(stderr, "nebu_SourceMusic destructor called\n");
#ifndef macintosh
SDL_SemWait(_sem);
#else
SDL_LockAudio();
#endif
free(_buffer);
if(_sample)
Sound_FreeSample( _sample );
_sample = NULL;
if(_filename)
free(_filename);
#ifndef macintosh
SDL_SemPost(_sem);
#else
SDL_UnlockAudio();
#endif
}
/*!
\fn void SourceMusic::CreateSample(void)
call this function only between semaphores
*/
void SourceMusic::CreateSample(void) {
_rwops = SDL_RWFromFile(_filename, "rb");
char *ext = _filename;
for(int i = 0; *(_filename + i); i++)
{
if(*(_filename + i) == '.')
ext = _filename + i + 1;
}
_sample = Sound_NewSample(_rwops, ext,
_system->GetAudioInfo(),
_sample_buffersize );
if(_sample == NULL) {
fprintf(stderr, "[error] failed loading sample type %s, from %s: %s\n", ext,
_filename, Sound_GetError());
return;
}
_read = 0;
_decoded = 0;
// fprintf(stderr, "created sample\n");
}
void SourceMusic::Load(char *filename) {
int n = strlen(filename);
_filename = (char*) malloc(n + 1);
memcpy(_filename, filename, n + 1);
CreateSample();
}
void SourceMusic::CleanUp(void) {
_read = 0;
_decoded = 0;
if(_sample != NULL)
Sound_FreeSample(_sample);
}
int SourceMusic::Mix(Uint8 *data, int len) {
if(_sample == NULL) return 0;
#ifndef macintosh
if( SDL_SemTryWait(_sem) ) {
fprintf(stderr, "semaphore locked, skipping mix\n");
return 0;
}
#endif
// printf("mixing %d bytes\n", len);
int volume = (int)(_volume * SDL_MIX_MAXVOLUME);
// fprintf(stderr, "setting volume to %.3f -> %d\n", _volume, volume);
// fprintf(stderr, "entering mixer\n");
if(len < (_decoded - _read + _buffersize) % _buffersize) {
// enough data to mix
if(_read + len <= _buffersize) {
SDL_MixAudio(data, _buffer + _read, len, volume);
_read = (_read + len) % _buffersize;
} else {
// wrap around in buffer
fprintf(stderr, "wrap around in buffer (%d, %d, %d)\n",
len, _read, _buffersize);
SDL_MixAudio(data, _buffer + _read, _buffersize - _read, volume);
len -= _buffersize - _read;
SDL_MixAudio(data + _buffersize - _read, _buffer, len, volume);
_read = len;
}
} else {
// buffer under-run
fprintf(stderr, "buffer underrun!\n");
// don't do anything
}
#ifndef macintosh
SDL_SemPost(_sem);
#endif
return 1;
}
void SourceMusic::Idle(void) {
if(_sample == NULL)
return;
// printf("idling\n");
while( _read == _decoded ||
(_read - _decoded + _buffersize) % _buffersize >
_sample_buffersize ) {
// if(_read == _decoded) printf("_read == _decoded == %d\n", _read);
// fill the buffer
int count = Sound_Decode(_sample);
// printf("adding %d bytes to buffer\n", count);
if(count <= _buffersize - _decoded) {
memcpy(_buffer + _decoded, _sample->buffer, count);
} else {
// wrapping around end of buffer (usually doesn't happen when
// _buffersize is a multiple of _sample_buffersize)
// printf("wrapping around end of buffer\n");
memcpy(_buffer + _decoded, _sample->buffer, _buffersize - _decoded);
memcpy(_buffer, (Uint8*) _sample->buffer + _buffersize - _decoded,
count - (_buffersize - _decoded));
}
_decoded = (_decoded + count) % _buffersize;
// check for end of sample, loop
if((_sample->flags & SOUND_SAMPLEFLAG_ERROR) ||
(_sample->flags & SOUND_SAMPLEFLAG_EOF)) {
// some error has occured, maybe end of sample reached
#ifndef macintosh
SDL_SemWait(_sem);
#else
SDL_LockAudio();
#endif
// todo: let playback finish, because there's still data
// in the buffer that has to be mixed
CleanUp();
// fprintf(stderr, "end of sample reached!\n");
if(_loop) {
// fprintf(stderr, "looping music\n");
if(_loop != 255)
_loop--;
CreateSample();
} else {
_isPlaying = 0;
// todo: notify sound system (maybe load another song?)
}
#ifndef macintosh
SDL_SemPost(_sem);
#else
SDL_UnlockAudio();
#endif
}
} // buffer has been filled
}
}
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