+#if defined(AUDIO_STREAMING_DSP)
+static void Mixer_Main_DSP()
+{
+ static short premix_first_buffer[DEFAULT_AUDIO_FRAGMENT_SIZE];
+ static long premix_last_buffer[DEFAULT_AUDIO_FRAGMENT_SIZE];
+ static byte playing_buffer[DEFAULT_AUDIO_FRAGMENT_SIZE];
+ boolean stereo;
+ int fragment_size;
+ int sample_bytes;
+ int max_sample_size;
+ int num_output_channels;
+ int i, j;
+
+ if (!mixer_active_channels)
+ return;
+
+ if (audio.device_fd < 0)
+ {
+ if ((audio.device_fd = OpenAudioDevice(audio.device_name)) < 0)
+ return;
+
+ InitAudioDevice(&afmt);
+ }
+
+ stereo = afmt.stereo;
+ fragment_size = afmt.fragment_size;
+ sample_bytes = (afmt.format & AUDIO_FORMAT_U8 ? 1 : 2);
+ num_output_channels = (stereo ? 2 : 1);
+ max_sample_size = fragment_size / (num_output_channels * sample_bytes);
+
+ /* first clear the last premixing buffer */
+ memset(premix_last_buffer, 0,
+ max_sample_size * num_output_channels * sizeof(long));
+
+ for(i=0; i<audio.num_channels; i++)
+ {
+ void *sample_ptr;
+ int sample_len;
+ int sample_pos;
+ int sample_size;
+
+ if (!mixer[i].active)
+ continue;
+
+ if (Mixer_ChannelExpired(i))
+ {
+ Mixer_StopChannel(i);
+ continue;
+ }
+
+ /* pointer, lenght and actual playing position of sound sample */
+ sample_ptr = mixer[i].data_ptr;
+ sample_len = mixer[i].data_len;
+ sample_pos = mixer[i].playing_pos;
+ sample_size = MIN(max_sample_size, sample_len - sample_pos);
+ mixer[i].playing_pos += sample_size;
+
+ /* copy original sample to first mixing buffer */
+ CopySampleToMixingBuffer(&mixer[i], sample_pos, sample_size,
+ premix_first_buffer, 0, num_output_channels);
+
+ /* are we about to restart a looping sound? */
+ if (IS_LOOP(mixer[i]) && sample_size < max_sample_size)
+ {
+ while (sample_size < max_sample_size)
+ {
+ int restarted_sample_size =
+ MIN(max_sample_size - sample_size, sample_len);
+
+ CopySampleToMixingBuffer(&mixer[i], 0, restarted_sample_size,
+ premix_first_buffer, sample_size,
+ num_output_channels);
+
+ mixer[i].playing_pos = restarted_sample_size;
+ sample_size += restarted_sample_size;
+ }
+ }
+
+ /* decrease volume if sound is fading out */
+ if (IS_FADING(mixer[i]) &&
+ mixer[i].volume >= SOUND_FADING_VOLUME_THRESHOLD)
+ mixer[i].volume -= SOUND_FADING_VOLUME_STEP;
+
+ /* adjust volume of actual sound sample */
+ if (mixer[i].volume != SOUND_MAX_VOLUME)
+ for(j=0; j<sample_size * num_output_channels; j++)
+ premix_first_buffer[j] =
+ mixer[i].volume * (long)premix_first_buffer[j] / SOUND_MAX_VOLUME;
+
+ /* adjust left and right channel volume due to stereo sound position */
+ if (stereo)
+ {
+ int left_volume = SOUND_VOLUME_LEFT(mixer[i].stereo_position);
+ int right_volume = SOUND_VOLUME_RIGHT(mixer[i].stereo_position);
+
+ for(j=0; j<sample_size; j++)
+ {
+ premix_first_buffer[2 * j + 0] =
+ left_volume * premix_first_buffer[2 * j + 0] / SOUND_MAX_LEFT2RIGHT;
+ premix_first_buffer[2 * j + 1] =
+ right_volume * premix_first_buffer[2 * j + 1] / SOUND_MAX_LEFT2RIGHT;
+ }
+ }
+
+ /* fill the last mixing buffer with stereo or mono sound */
+ for(j=0; j<sample_size * num_output_channels; j++)
+ premix_last_buffer[j] += premix_first_buffer[j];
+
+ /* delete completed sound entries from the mixer */
+ if (mixer[i].playing_pos >= mixer[i].data_len)
+ {
+ if (IS_LOOP(mixer[i]))
+ mixer[i].playing_pos = 0;
+ else
+ Mixer_StopChannel(i);
+ }
+ else if (mixer[i].volume <= SOUND_FADING_VOLUME_THRESHOLD)
+ Mixer_StopChannel(i);
+ }
+
+ /* prepare final playing buffer according to system audio format */
+ for(i=0; i<max_sample_size * num_output_channels; i++)
+ {
+ /* cut off at 17 bit value */
+ if (premix_last_buffer[i] < -65535)
+ premix_last_buffer[i] = -65535;
+ else if (premix_last_buffer[i] > 65535)
+ premix_last_buffer[i] = 65535;
+
+ /* shift to 16 bit value */
+ premix_last_buffer[i] >>= 1;
+
+ if (afmt.format & AUDIO_FORMAT_U8)
+ {
+ playing_buffer[i] = (premix_last_buffer[i] >> 8) ^ 0x80;
+ }
+ else if (afmt.format & AUDIO_FORMAT_LE) /* 16 bit */
+ {
+ playing_buffer[2 * i + 0] = premix_last_buffer[i] & 0xff;
+ playing_buffer[2 * i + 1] = premix_last_buffer[i] >> 8;
+ }
+ else /* big endian */
+ {
+ playing_buffer[2 * i + 0] = premix_last_buffer[i] >> 8;
+ playing_buffer[2 * i + 1] = premix_last_buffer[i] & 0xff;
+ }
+ }
+
+ /* finally play the sound fragment */
+ write(audio.device_fd, playing_buffer, fragment_size);
+
+ if (!mixer_active_channels)
+ CloseAudioDevice(&audio.device_fd);
+}
+
+#else /* !AUDIO_STREAMING_DSP */
+
+static int Mixer_Main_SimpleAudio(SoundControl snd_ctrl)
+{
+ static short premix_first_buffer[DEFAULT_AUDIO_FRAGMENT_SIZE];
+ static byte playing_buffer[DEFAULT_AUDIO_FRAGMENT_SIZE];
+ int max_sample_size = DEFAULT_AUDIO_FRAGMENT_SIZE;
+ int num_output_channels = 1;
+ void *sample_ptr;
+ int sample_len;
+ int sample_pos;
+ int sample_size;
+ int i, j;
+
+ i = 1;
+
+ /* pointer, lenght and actual playing position of sound sample */
+ sample_ptr = mixer[i].data_ptr;
+ sample_len = mixer[i].data_len;
+ sample_pos = mixer[i].playing_pos;
+ sample_size = MIN(max_sample_size, sample_len - sample_pos);
+ mixer[i].playing_pos += sample_size;
+
+ /* copy original sample to first mixing buffer */
+ CopySampleToMixingBuffer(&mixer[i], sample_pos, sample_size,
+ premix_first_buffer, 0, num_output_channels);
+
+ /* adjust volume of actual sound sample */
+ if (mixer[i].volume != SOUND_MAX_VOLUME)
+ for(j=0; j<sample_size; j++)
+ premix_first_buffer[j] =
+ mixer[i].volume * (long)premix_first_buffer[j] / SOUND_MAX_VOLUME;
+
+ /* might be needed for u-law /dev/audio */
+#if 1
+ for(j=0; j<sample_size; j++)
+ playing_buffer[j] =
+ linear_to_ulaw(premix_first_buffer[j]);
+#endif
+
+ /* delete completed sound entries from the mixer */
+ if (mixer[i].playing_pos >= mixer[i].data_len)
+ Mixer_StopChannel(i);
+
+ for(i=0; i<sample_size; i++)
+ playing_buffer[i] = (premix_first_buffer[i] >> 8) ^ 0x80;
+
+ /* finally play the sound fragment */
+ write(audio.device_fd, playing_buffer, sample_size);
+
+ return sample_size;
+}
+#endif /* !AUDIO_STREAMING_DSP */
+
+void Mixer_Main()
+{
+ SoundControl snd_ctrl;
+ fd_set mixer_fdset;
+
+ close(audio.mixer_pipe[1]); /* no writing into pipe needed */
+
+ Mixer_InitChannels();
+
+#if defined(PLATFORM_HPUX)
+ InitAudioDevice(&afmt);
+#endif
+
+ FD_ZERO(&mixer_fdset);
+ FD_SET(audio.mixer_pipe[0], &mixer_fdset);
+
+ while(1) /* wait for sound playing commands from client */
+ {
+ struct timeval delay = { 0, 0 };
+
+ FD_SET(audio.mixer_pipe[0], &mixer_fdset);
+ select(audio.mixer_pipe[0] + 1, &mixer_fdset, NULL, NULL, NULL);
+ if (!FD_ISSET(audio.mixer_pipe[0], &mixer_fdset))
+ continue;
+
+ ReadSoundControlFromMainProcess(&snd_ctrl);
+
+ HandleSoundRequest(snd_ctrl);
+
+#if defined(AUDIO_STREAMING_DSP)
+
+ while (mixer_active_channels &&
+ select(audio.mixer_pipe[0] + 1,
+ &mixer_fdset, NULL, NULL, &delay) < 1)
+ {
+ FD_SET(audio.mixer_pipe[0], &mixer_fdset);
+
+ Mixer_Main_DSP();
+ }
+
+#else /* !AUDIO_STREAMING_DSP */
+
+ if (!snd_ctrl.active || IS_LOOP(snd_ctrl) ||
+ (audio.device_fd = OpenAudioDevice(audio.device_name)) < 0)
+ continue;
+
+ InitAudioDevice(&afmt);
+
+ delay.tv_sec = 0;
+ delay.tv_usec = 0;
+
+ while (mixer_active_channels &&
+ select(audio.mixer_pipe[0] + 1,
+ &mixer_fdset, NULL, NULL, &delay) < 1)
+ {
+ int wait_percent = 90; /* wait 90% of the real playing time */
+ int sample_size;
+
+ FD_SET(audio.mixer_pipe[0], &mixer_fdset);
+
+ sample_size = Mixer_Main_SimpleAudio(snd_ctrl);
+
+ delay.tv_sec = 0;
+ delay.tv_usec =
+ ((sample_size * 10 * wait_percent) / afmt.sample_rate) * 1000;
+ }
+
+ CloseAudioDevice(&audio.device_fd);
+
+ Mixer_InitChannels(); /* remove all sounds from mixer */
+
+#endif /* !AUDIO_STREAMING_DSP */
+ }
+}
+#endif /* AUDIO_UNIX_NATIVE */
+
+
+#if defined(AUDIO_UNIX_NATIVE) && !defined(AUDIO_STREAMING_DSP)