cleanup and bufferhandling fix by Joy Ping <joy at pingfm.org>. Bufferhandling fix based on idea by Marius David <marius at rohost.com>

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@6590 b3059339-0415-0410-9bf9-f77b7e298cf2

2 files changed, 480 insertions, 346 deletions

diff --git a/libao2/ao_alsa1x.c b/libao2/ao_alsa1x.c
index abab25147b..48e0b227b6 100644
--- a/libao2/ao_alsa1x.c
+++ b/libao2/ao_alsa1x.c
@@ -3,16 +3,17 @@
 
   (C) Alex Beregszaszi <alex@naxine.org>
   
-  modified for better alsa-0.9.0beta8a-support by Joy Winter <joy@pingfm.org>
+  modified for better alsa-0.9.0beta12(rc1)-support by Joy Winter <joy@pingfm.org>
   additional AC3 passthrough support by Andy Lo A Foe <andy@alsaplayer.org>
   
-  This driver is still at alpha stage. 
-  If you want stable sound-support use the OSS emulation instead.
-  
   Any bugreports regarding to this driver are welcome either to the mplayer-user-mailinglist or directly to the authors.
 */
 
 #include <errno.h>
+#include <sys/time.h>
+#include <stdlib.h>
+//#include <unistd.h>
+//#include <string.h>
 
 #include "../config.h"
 
@@ -46,13 +47,23 @@ static snd_pcm_format_t alsa_format;
 static snd_pcm_hw_params_t *alsa_hwparams;
 static snd_pcm_sw_params_t *alsa_swparams;
 static char *alsa_device;
-#define ALSA_DEVICE_SIZE 48
 
-static int alsa_fragsize = 8192; /* possible 4096, original 8192 */
+static int alsa_fragsize = OUTBURST; /* possible 4096, original 8192, OUTBURST is set statically to 512 in config.h but now its not used cause chunksize is allocated dynamically. */
 static int alsa_fragcount = 8;
 
 static int chunk_size = -1;
-static int start_delay = 1;
+static int buffer_size = 0;
+static int start_delay = 0;
+static int stop_delay = 0;
+static size_t bits_per_sample, bits_per_frame;
+static size_t chunk_bytes;
+
+#define ALSA_DEVICE_SIZE 48
+
+#define BUFFERTIME /* last undef */
+#undef SET_PERIOD /* only function now is to set chunksize staticaly, last defined */
+#define SW_PARAMS /* last undef */
+
 
 snd_pcm_t *
 spdif_init(int acard, int adevice)
@@ -178,12 +189,6 @@ static int control(int cmd, int arg)
     return(CONTROL_UNKNOWN);
 }
 
-#undef start /* orig. undef */
-#define buffsize 
-#define buffertime /* orig. undef? */
-#define set_period
-#define sw_params /* orig. undef */
-#undef set_start_mode /* orig. undef */
 
 /*
     open & setup audio device
@@ -198,7 +203,7 @@ static int init(int rate_hz, int channels, int format, int flags)
     size_t xfer_align; //new
     snd_pcm_uframes_t start_threshold, stop_threshold; //new
 
-    printf("alsa-init: this driver is still at alpha-stage. if you want stable sound support use the OSS emulation instead.\n");    
+    printf("alsa-init: testing and bugreports are welcome.\n");    
     printf("alsa-init: requested format: %d Hz, %d channels, %s\n", rate_hz,
 	channels, audio_out_format_name(format));
 
@@ -265,29 +270,47 @@ static int init(int rate_hz, int channels, int format, int flags)
 	    break;
     }
     
-    if ((err = snd_pcm_info_malloc(&alsa_info)) < 0)
-    {
-	printf("alsa-init: memory allocation error: %s\n", snd_strerror(err));
-	return(0);
-    }
-
-    if (ao_subdevice != NULL)
+    if (ao_subdevice != NULL) // ?? makes no sense
 	alsa_device = ao_subdevice;
 
     if (alsa_device == NULL)
-    {
-	if ((alsa_device = malloc(ALSA_DEVICE_SIZE)) == NULL)
-	{
+      {
+	int tmp_device, tmp_subdevice, err;
+
+	if ((err = snd_pcm_info_malloc(&alsa_info)) < 0)
+	  {
+	    printf("alsa-init: memory allocation error: %s\n", snd_strerror(err));
+	    return(0);
+	  }
+	
+	if ((alsa_device = alloca(ALSA_DEVICE_SIZE)) == NULL)
+	  {
 	    printf("alsa-init: memory allocation error: %s\n", strerror(errno));
 	    return(0);
-	}
+	  }
 
-	snprintf(alsa_device, ALSA_DEVICE_SIZE, "hw:%d,%d",
-	    snd_pcm_info_get_device(alsa_info),
-	    snd_pcm_info_get_subdevice(alsa_info));
+	if ((tmp_device = snd_pcm_info_get_device(alsa_info)) < 0)
+	  {
+	    printf("alsa-init: cant get device\n");
+	    return(0);
+	  }
+
+	if ((tmp_subdevice = snd_pcm_info_get_subdevice(alsa_info)) < 0)
+	  {
+	    printf("alsa-init: cant get subdevice\n");
+	    return(0);
+	  }
+	
+	if (verbose)
+	  printf("alsa-init: got device=%i, subdevice=%i\n", tmp_device, tmp_subdevice);
+
+	if ((err = snprintf(alsa_device, ALSA_DEVICE_SIZE, "hw:%1d,%1d", tmp_device, tmp_subdevice)) <= 0)
+	  {
+	    printf("alsa-init: cant wrote device-id\n");
+	  }
 
 	snd_pcm_info_free(alsa_info);
-    }
+      }
 
     printf("alsa-init: %d soundcard%s found, using: %s\n", cards+1,
 	(cards >= 0) ? "" : "s", alsa_device);
@@ -298,16 +321,17 @@ static int init(int rate_hz, int channels, int format, int flags)
     }	    
    
     if (!alsa_handler) {
-	    if ((err = snd_pcm_open(&alsa_handler, alsa_device, SND_PCM_STREAM_PLAYBACK,
-					    0)) < 0)
+	    if ((err = snd_pcm_open(&alsa_handler,alsa_device,SND_PCM_STREAM_PLAYBACK,0)) < 0)
 	    {
 		    printf("alsa-init: playback open error: %s\n", snd_strerror(err));
 		    return(0);
 	    }
     }	    
 
-    snd_pcm_hw_params_malloc(&alsa_hwparams);
+    snd_pcm_hw_params_alloca(&alsa_hwparams);
     snd_pcm_sw_params_alloca(&alsa_swparams);
+
+    // setting hw-parameters
     if ((err = snd_pcm_hw_params_any(alsa_handler, alsa_hwparams)) < 0)
     {
 	printf("alsa-init: unable to get initial parameters: %s\n",
@@ -340,7 +364,6 @@ static int init(int rate_hz, int channels, int format, int flags)
     }
 
         if ((err = snd_pcm_hw_params_set_rate_near(alsa_handler, alsa_hwparams, ao_data.samplerate, 0)) < 0) 
-/* was originally only snd_pcm_hw_params_set_rate jp*/ 
         {
     	printf("alsa-init: unable to set samplerate-2: %s\n",
     	    snd_strerror(err));
@@ -348,37 +371,18 @@ static int init(int rate_hz, int channels, int format, int flags)
     	return(0);
         }
 
-#ifdef set_period
+
+#ifdef SET_PERIOD
     {
-	if ((err = snd_pcm_hw_params_set_period_size(alsa_handler, alsa_hwparams, alsa_fragsize / 4, 0)) < 0)
+	if ((err = snd_pcm_hw_params_set_period_size(alsa_handler, alsa_hwparams, alsa_fragsize, 0)) < 0)
 	{
-	    printf("alsa-init: unable to set periodsize: %s\n",
-		snd_strerror(err));
+	    printf("alsa-init: unable to set periodsize: %s\n", snd_strerror(err));
 	    return(0);
 	}
-		if ((err = snd_pcm_hw_params_set_periods(alsa_handler, alsa_hwparams, alsa_fragcount, 0)) < 0)
-		{
-		    printf("alsa-init: unable to set periods: %s\n",
-			snd_strerror(err));
-		    return(0);
-		}
-    }
-#endif
-#ifdef buffsize
-    if ((err = snd_pcm_hw_params_get_buffer_size(alsa_hwparams)) < 0)
-    {
-	printf("alsa-init: unable to get buffer size: %s\n",
-	    snd_strerror(err));
-	return(0);
-    } else
-    {
-	ao_data.buffersize = err;
-        if (verbose)
-	    printf("alsa-init: got buffersize %i\n", ao_data.buffersize);
     }
 #endif
 
-#ifdef buffertime
+#ifdef BUFFERTIME
     {
       int alsa_buffer_time = 500000; /* original 60 */
 
@@ -397,105 +401,150 @@ static int init(int rate_hz, int channels, int format, int flags)
 		snd_strerror(err));
 	    return(0);
 	}
-	printf("alsa-init: buffer_time: %d, period_time :%d\n",
-	    alsa_buffer_time, err);
+	if (verbose)
+	  printf("alsa-init: buffer_time: %d, period_time :%d\n",alsa_buffer_time, err);
     }
 #endif
 
+    /* get chunk-size */
+    if ((err = snd_pcm_hw_params_get_period_size(alsa_hwparams, 0)) < 0)
+      {
+	printf("alsa-init: unable to get chunk-size in hw-params: %s\n", snd_strerror(err));
+	return(0);
+      } else
+	{
+	  chunk_size = err;
+	  if (verbose) {printf("alsa-init: got chunksize %i\n", chunk_size);}
+	}
+
+    /* get buffer size */
+    if ((err = snd_pcm_hw_params_get_buffer_size(alsa_hwparams)) < 0)
+    {
+      printf("alsa-init: unable to get buffersize in hw-params: %s\n", snd_strerror(err));
+      return(0);
+    } else
+      {
+      ao_data.buffersize = err;
+      if (verbose) {printf("alsa-init: got buffersize %i\n", ao_data.buffersize);}
+      }
+    
+    if (MAX_OUTBURST > ao_data.buffersize) { //warning if MAX_OUTBURST is bigger than buffersize
+      printf("alsa-init: WARNING! MAX_OUTBURST exceeds your available buffersize.\nalsa-init: MAX_OUTBURST=%i, buffersize=%i\n",MAX_OUTBURST,ao_data.buffersize);}
+
+    if (chunk_size == ao_data.buffersize)
+      {
+      printf("alsa-init: Can't use period equal to buffer size (%u == %lu)", chunk_size, (long)buffer_size);
+      return(0);
+      }
+
+    /* finally install hardware parameters */
     if ((err = snd_pcm_hw_params(alsa_handler, alsa_hwparams)) < 0)
     {
-	printf("alsa-init: unable to set parameters: %s\n",
+	printf("alsa-init: unable to set hw-parameters: %s\n",
 	    snd_strerror(err));
 	return(0);
     }
+    // end setting hw-params
 
-#ifdef sw_params
+#ifdef SW_PARAMS
     {
-    chunk_size = snd_pcm_hw_params_get_period_size(alsa_hwparams, 0);
-    start_threshold = (double) ao_data.samplerate * start_delay / 1000000;
-    xfer_align = snd_pcm_sw_params_get_xfer_align(alsa_swparams);
+      size_t n;
+      xfer_align = snd_pcm_sw_params_get_xfer_align(alsa_swparams);
+      if (xfer_align == 0)
+	xfer_align = 4;
+      n = (ao_data.buffersize / xfer_align) * xfer_align;
+
+      if (start_delay <= 0) {
+	start_threshold = n + (double) ao_data.samplerate * start_delay / 1000000;
+      } else {
+	start_threshold = (double) ao_data.samplerate * start_delay / 1000000;
+      }
+      if (start_threshold < 1)
+	start_threshold = 1;
+      if (start_threshold > n)
+	start_threshold = n;
+
+      if (stop_delay <= 0) {
+	stop_threshold = ao_data.buffersize + (double) ao_data.samplerate * stop_delay / 1000000;
+      } else {
+	stop_threshold = (double) ao_data.samplerate * stop_delay / 1000000;
+      }
+
+      if (verbose) {
+	printf("alsa-init: start_threshold=%lu, stop_threshold=%lu\n",start_threshold,stop_threshold);
+	printf("alsa-init: n=%i\n", n);
+      }
 
     if ((err = snd_pcm_sw_params_current(alsa_handler, alsa_swparams)) < 0)
-    {
-	printf("alsa-init: unable to get parameters: %s\n",
-	    snd_strerror(err));
+      {
+	printf("alsa-init: unable to get parameters: %s\n",snd_strerror(err));
 	return(0);
-    }
+      }
+
+    //set min available frames to consider pcm ready (4)
+    if ((err = snd_pcm_sw_params_set_avail_min(alsa_handler, alsa_swparams, 4)) < 0)
+      {
+	printf("alsa-init: unable to set avail_min %s\n",snd_strerror(err));
+	return(0);
+      }
 	
-	if ((err = snd_pcm_sw_params_set_avail_min(alsa_handler, alsa_swparams, chunk_size)) < 0)
-	  {
-	    printf("alsa-init: unable to set avail_min %s\n",snd_strerror(err));
-	    return(0);
-	  }
+    if ((err = snd_pcm_sw_params_set_start_threshold(alsa_handler, alsa_swparams, start_threshold)) < 0)
+      {
+	printf("alsa-init: unable to set start_threshold %s\n",snd_strerror(err));
+	return(0);
+      }
 
+    if ((err = snd_pcm_sw_params_set_stop_threshold(alsa_handler, alsa_swparams, stop_threshold)) < 0)
+      {
+	printf("alsa-init: unable to set stop_threshold %s\n",snd_strerror(err));
+	return(0);
+      }
 
-	
-	if ((err = snd_pcm_sw_params_set_start_threshold(alsa_handler, alsa_swparams, start_threshold)) < 0)
-	  {
-	    printf("alsa-init: unable to set start_threshold %s\n",snd_strerror(err));
-	    return(0);
-	  }
-    } 
-    //      if ((err = snd_pcm_sw_params_set_xfer_align(alsa_handler, alsa_swparams, xfer_align)) < 0)
-    //{
-    //	printf("alsa-init: unable to set xfer_align: %s\n",
-    //	    snd_strerror(err));
-    //	return(0);
-    //}
-
-#ifdef set_start_mode
-    if ((err = snd_pcm_sw_params_set_start_mode(alsa_handler, alsa_swparams,
-	SND_PCM_START_DATA)) < 0)
-    {
-	printf("alsa-init: unable to set start mode: %s\n",
-	    snd_strerror(err));
+    //transfers stream aligned to 4 in nonblocking-mode it would be 1
+    if ((err = snd_pcm_sw_params_set_xfer_align(alsa_handler, alsa_swparams, 4)) < 0)
+      {
+	printf("alsa-init: unable to set xfer_align: %s\n",snd_strerror(err));
 	return(0);
-    }
-#endif
+      }
 
     if ((err = snd_pcm_sw_params(alsa_handler, alsa_swparams)) < 0)
-    {
-	printf("alsa-init: unable to set parameters: %s\n",
-	    snd_strerror(err));
+      {
+	printf("alsa-init: unable to install sw-params\n");
 	return(0);
+      }
+
+    bits_per_sample = snd_pcm_format_physical_width(alsa_format);
+    bits_per_frame = bits_per_sample * channels;
+    chunk_bytes = chunk_size * bits_per_frame / 8;
+
+    if (verbose) {
+      printf("alsa-init: bits per sample (bps)=%i, bits per frame (bpf)=%i, chunk_bytes=%i\n",bits_per_sample,bits_per_frame,chunk_bytes);}
     }
 
-//    snd_pcm_sw_params_default(alsa_handler, alsa_swparams);
-#endif
+#endif //end swparams
+
     if ((err = snd_pcm_prepare(alsa_handler)) < 0)
     {
 	printf("alsa-init: pcm prepare error: %s\n", snd_strerror(err));
 	return(0);
     }
 
-#ifdef start
-    if ((err = snd_pcm_start(alsa_handler)) < 0)
-    {
-	printf("alsa-init: pcm start error: %s\n", snd_strerror(err));
-	if (err != -EPIPE)
-	    return(0);
-	if ((err = snd_pcm_start(alsa_handler)) < 0)
-	{
-	    printf("alsa-init: pcm start error: %s\n", snd_strerror(err));
-		return(0);
-	}
-    }
-#endif
-    printf("AUDIO: %d Hz/%d channels/%d bpf/%d bytes buffer/%s\n",
+    printf("alsa9: %d Hz/%d channels/%d bpf/%d bytes buffer/%s\n",
 	ao_data.samplerate, ao_data.channels, ao_data.bps, ao_data.buffersize,
 	snd_pcm_format_description(alsa_format));
     return(1);
-}
+} // end init
+
 
 /* close audio device */
 static void uninit()
 {
     int err;
 
-    if (alsa_device != NULL)
-	free(alsa_device);
+    //if (alsa_device != NULL)
+    //free(alsa_device);
 
-    snd_pcm_hw_params_free(alsa_hwparams);
+    //snd_pcm_hw_params_free(alsa_hwparams);
 
     if ((err = snd_pcm_drain(alsa_handler)) < 0)
     {
@@ -503,19 +552,16 @@ static void uninit()
 	return;
     }
 
-#ifdef start
-    if ((err = snd_pcm_reset(alsa_handler)) < 0)
-    {
-	printf("alsa-uninit: pcm reset error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
-
     if ((err = snd_pcm_close(alsa_handler)) < 0)
     {
 	printf("alsa-uninit: pcm close error: %s\n", snd_strerror(err));
 	return;
     }
+    else {
+      alsa_handler = NULL;
+      alsa_device = NULL;
+      printf("alsa-uninit: pcm closed\n");
+    }
 }
 
 static void audio_pause()
@@ -546,14 +592,6 @@ static void audio_resume()
 	printf("alsa-resume: pcm prepare error: %s\n", snd_strerror(err));
 	return;
     }
-
-#ifdef start
-    if ((err = snd_pcm_start(alsa_handler)) < 0)
-    {
-	printf("alsa-resume: pcm start error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
 }
 
 /* stop playing and empty buffers (for seeking/pause) */
@@ -567,62 +605,90 @@ static void reset()
 	return;
     }
 
-#ifdef start
-    if ((err = snd_pcm_reset(alsa_handler)) < 0)
-    {
-	printf("alsa-reset: pcm reset error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
-
     if ((err = snd_pcm_prepare(alsa_handler)) < 0)
     {
 	printf("alsa-reset: pcm prepare error: %s\n", snd_strerror(err));
 	return;
     }
 
-#ifdef start
-    if ((err = snd_pcm_start(alsa_handler)) < 0)
-    {
-	printf("alsa-reset: pcm start error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
 }
 
+#ifndef timersub
+#define timersub(a, b, result) \
+do { \
+	(result)->tv_sec = (a)->tv_sec - (b)->tv_sec; \
+  (result)->tv_usec = (a)->tv_usec - (b)->tv_usec; \
+  if ((result)->tv_usec < 0) { \
+		--(result)->tv_sec; \
+		(result)->tv_usec += 1000000; \
+	} \
+} while (0)
+#endif
+
 /*
     plays 'len' bytes of 'data'
     returns: number of bytes played
+    modified last at 26.06.02 by jp
 */
 
 static int play(void* data, int len, int flags)
 {
-    int got_len;
-	
-    got_len = snd_pcm_writei(alsa_handler, data, len / 4);
+
+  snd_pcm_status_t *status;
+
+  int num_frames=len/ao_data.bps;
+  signed short *output_samples=data;
+  snd_pcm_sframes_t res = 0;
+
+  if (!alsa_handler) {
+    printf("alsa-play: device configuration error");
+    return 0;
+  }
+
+  do {
+    if (res == -EPIPE) {  /* underrun */
+      snd_pcm_status_alloca(&status);
+      if ((res = snd_pcm_status(alsa_handler, status))<0) {
+	printf("alsa-play: buffer underrun. can't determine length");
+      } else {
+	if (snd_pcm_status_get_state(status) == SND_PCM_STATE_XRUN) {
+	  struct timeval now, diff, tstamp;
+	  gettimeofday(&now, 0);
+	  snd_pcm_status_get_trigger_tstamp(status, &tstamp);
+	  timersub(&now, &tstamp, &diff);
+	  printf("alsa-play: xrun of at least %.3f msecs. resetting stream",
+		 diff.tv_sec * 1000 + diff.tv_usec / 1000.0);
+	} else 
+	  printf("alsa-play: xrun. can't determine length");
+      }	
+      res = snd_pcm_prepare(alsa_handler);
+    }
+    else if (res == -ESTRPIPE) {	/* suspend */
+      printf("alsa-play: pcm in suspend mode. trying to resume");
+      while ((res = snd_pcm_resume(alsa_handler)) == -EAGAIN)
+	sleep(1);
+      if (res < 0)
+	res = snd_pcm_prepare(alsa_handler);
+    }
     
-    //if ((got_len = snd_pcm_writei(alsa_handler, data, (len/ao_data.bps))) != (len/ao_data.bps)) {     
-    //SHOULD BE FIXED      
-	if (got_len == -EPIPE) /* underrun? */
-	{
-	    printf("alsa-play: alsa underrun, resetting stream\n");
-	    if ((got_len = snd_pcm_prepare(alsa_handler)) < 0)
-	    {
-		printf("alsa-play: playback prepare error: %s\n", snd_strerror(got_len));
-		return(0);
-	    }
-	    if ((got_len = snd_pcm_writei(alsa_handler, data, (len/ao_data.bps))) != (len/ao_data.bps))
-	    {
-		printf("alsa-play: write error after reset: %s - giving up\n",
-		    snd_strerror(got_len));
-		return(0);
-	    }
-	    return(len); /* 2nd write was ok */
+    if (res >= 0)
+      res = snd_pcm_writei(alsa_handler, (void *)output_samples, num_frames);
+    
+    if (res > 0) {
+      output_samples += ao_data.channels * res;
+      num_frames -= res;
     }
-    return(len);
-    //}
+
+  } while (res == -EPIPE || num_frames > 0);
+
+  if (res < 0) {
+    printf("alsa-play: write error %s", snd_strerror(res));
+    return 0;
+  }
+  return res < 0 ? (int)res : len;
 }
 
+
 /* how many byes are free in the buffer */
 static int get_space()
 {
@@ -655,7 +721,8 @@ static int get_space()
     snd_pcm_status_free(status);
     
     if (ret < 0)
-	ret = 0;
+      ret = 0;
+    //printf("alsa-space: free space = %i",ret);
     return(ret);
 }
 
@@ -691,6 +758,6 @@ static float get_delay()
     snd_pcm_status_free(status);
 
     if (ret < 0)
-	ret = 0;
+      ret = 0;
     return(ret);
 }
diff --git a/libao2/ao_alsa9.c b/libao2/ao_alsa9.c
index abab25147b..48e0b227b6 100644
--- a/libao2/ao_alsa9.c
+++ b/libao2/ao_alsa9.c
@@ -3,16 +3,17 @@
 
   (C) Alex Beregszaszi <alex@naxine.org>
   
-  modified for better alsa-0.9.0beta8a-support by Joy Winter <joy@pingfm.org>
+  modified for better alsa-0.9.0beta12(rc1)-support by Joy Winter <joy@pingfm.org>
   additional AC3 passthrough support by Andy Lo A Foe <andy@alsaplayer.org>
   
-  This driver is still at alpha stage. 
-  If you want stable sound-support use the OSS emulation instead.
-  
   Any bugreports regarding to this driver are welcome either to the mplayer-user-mailinglist or directly to the authors.
 */
 
 #include <errno.h>
+#include <sys/time.h>
+#include <stdlib.h>
+//#include <unistd.h>
+//#include <string.h>
 
 #include "../config.h"
 
@@ -46,13 +47,23 @@ static snd_pcm_format_t alsa_format;
 static snd_pcm_hw_params_t *alsa_hwparams;
 static snd_pcm_sw_params_t *alsa_swparams;
 static char *alsa_device;
-#define ALSA_DEVICE_SIZE 48
 
-static int alsa_fragsize = 8192; /* possible 4096, original 8192 */
+static int alsa_fragsize = OUTBURST; /* possible 4096, original 8192, OUTBURST is set statically to 512 in config.h but now its not used cause chunksize is allocated dynamically. */
 static int alsa_fragcount = 8;
 
 static int chunk_size = -1;
-static int start_delay = 1;
+static int buffer_size = 0;
+static int start_delay = 0;
+static int stop_delay = 0;
+static size_t bits_per_sample, bits_per_frame;
+static size_t chunk_bytes;
+
+#define ALSA_DEVICE_SIZE 48
+
+#define BUFFERTIME /* last undef */
+#undef SET_PERIOD /* only function now is to set chunksize staticaly, last defined */
+#define SW_PARAMS /* last undef */
+
 
 snd_pcm_t *
 spdif_init(int acard, int adevice)
@@ -178,12 +189,6 @@ static int control(int cmd, int arg)
     return(CONTROL_UNKNOWN);
 }
 
-#undef start /* orig. undef */
-#define buffsize 
-#define buffertime /* orig. undef? */
-#define set_period
-#define sw_params /* orig. undef */
-#undef set_start_mode /* orig. undef */
 
 /*
     open & setup audio device
@@ -198,7 +203,7 @@ static int init(int rate_hz, int channels, int format, int flags)
     size_t xfer_align; //new
     snd_pcm_uframes_t start_threshold, stop_threshold; //new
 
-    printf("alsa-init: this driver is still at alpha-stage. if you want stable sound support use the OSS emulation instead.\n");    
+    printf("alsa-init: testing and bugreports are welcome.\n");    
     printf("alsa-init: requested format: %d Hz, %d channels, %s\n", rate_hz,
 	channels, audio_out_format_name(format));
 
@@ -265,29 +270,47 @@ static int init(int rate_hz, int channels, int format, int flags)
 	    break;
     }
     
-    if ((err = snd_pcm_info_malloc(&alsa_info)) < 0)
-    {
-	printf("alsa-init: memory allocation error: %s\n", snd_strerror(err));
-	return(0);
-    }
-
-    if (ao_subdevice != NULL)
+    if (ao_subdevice != NULL) // ?? makes no sense
 	alsa_device = ao_subdevice;
 
     if (alsa_device == NULL)
-    {
-	if ((alsa_device = malloc(ALSA_DEVICE_SIZE)) == NULL)
-	{
+      {
+	int tmp_device, tmp_subdevice, err;
+
+	if ((err = snd_pcm_info_malloc(&alsa_info)) < 0)
+	  {
+	    printf("alsa-init: memory allocation error: %s\n", snd_strerror(err));
+	    return(0);
+	  }
+	
+	if ((alsa_device = alloca(ALSA_DEVICE_SIZE)) == NULL)
+	  {
 	    printf("alsa-init: memory allocation error: %s\n", strerror(errno));
 	    return(0);
-	}
+	  }
 
-	snprintf(alsa_device, ALSA_DEVICE_SIZE, "hw:%d,%d",
-	    snd_pcm_info_get_device(alsa_info),
-	    snd_pcm_info_get_subdevice(alsa_info));
+	if ((tmp_device = snd_pcm_info_get_device(alsa_info)) < 0)
+	  {
+	    printf("alsa-init: cant get device\n");
+	    return(0);
+	  }
+
+	if ((tmp_subdevice = snd_pcm_info_get_subdevice(alsa_info)) < 0)
+	  {
+	    printf("alsa-init: cant get subdevice\n");
+	    return(0);
+	  }
+	
+	if (verbose)
+	  printf("alsa-init: got device=%i, subdevice=%i\n", tmp_device, tmp_subdevice);
+
+	if ((err = snprintf(alsa_device, ALSA_DEVICE_SIZE, "hw:%1d,%1d", tmp_device, tmp_subdevice)) <= 0)
+	  {
+	    printf("alsa-init: cant wrote device-id\n");
+	  }
 
 	snd_pcm_info_free(alsa_info);
-    }
+      }
 
     printf("alsa-init: %d soundcard%s found, using: %s\n", cards+1,
 	(cards >= 0) ? "" : "s", alsa_device);
@@ -298,16 +321,17 @@ static int init(int rate_hz, int channels, int format, int flags)
     }	    
    
     if (!alsa_handler) {
-	    if ((err = snd_pcm_open(&alsa_handler, alsa_device, SND_PCM_STREAM_PLAYBACK,
-					    0)) < 0)
+	    if ((err = snd_pcm_open(&alsa_handler,alsa_device,SND_PCM_STREAM_PLAYBACK,0)) < 0)
 	    {
 		    printf("alsa-init: playback open error: %s\n", snd_strerror(err));
 		    return(0);
 	    }
     }	    
 
-    snd_pcm_hw_params_malloc(&alsa_hwparams);
+    snd_pcm_hw_params_alloca(&alsa_hwparams);
     snd_pcm_sw_params_alloca(&alsa_swparams);
+
+    // setting hw-parameters
     if ((err = snd_pcm_hw_params_any(alsa_handler, alsa_hwparams)) < 0)
     {
 	printf("alsa-init: unable to get initial parameters: %s\n",
@@ -340,7 +364,6 @@ static int init(int rate_hz, int channels, int format, int flags)
     }
 
         if ((err = snd_pcm_hw_params_set_rate_near(alsa_handler, alsa_hwparams, ao_data.samplerate, 0)) < 0) 
-/* was originally only snd_pcm_hw_params_set_rate jp*/ 
         {
     	printf("alsa-init: unable to set samplerate-2: %s\n",
     	    snd_strerror(err));
@@ -348,37 +371,18 @@ static int init(int rate_hz, int channels, int format, int flags)
     	return(0);
         }
 
-#ifdef set_period
+
+#ifdef SET_PERIOD
     {
-	if ((err = snd_pcm_hw_params_set_period_size(alsa_handler, alsa_hwparams, alsa_fragsize / 4, 0)) < 0)
+	if ((err = snd_pcm_hw_params_set_period_size(alsa_handler, alsa_hwparams, alsa_fragsize, 0)) < 0)
 	{
-	    printf("alsa-init: unable to set periodsize: %s\n",
-		snd_strerror(err));
+	    printf("alsa-init: unable to set periodsize: %s\n", snd_strerror(err));
 	    return(0);
 	}
-		if ((err = snd_pcm_hw_params_set_periods(alsa_handler, alsa_hwparams, alsa_fragcount, 0)) < 0)
-		{
-		    printf("alsa-init: unable to set periods: %s\n",
-			snd_strerror(err));
-		    return(0);
-		}
-    }
-#endif
-#ifdef buffsize
-    if ((err = snd_pcm_hw_params_get_buffer_size(alsa_hwparams)) < 0)
-    {
-	printf("alsa-init: unable to get buffer size: %s\n",
-	    snd_strerror(err));
-	return(0);
-    } else
-    {
-	ao_data.buffersize = err;
-        if (verbose)
-	    printf("alsa-init: got buffersize %i\n", ao_data.buffersize);
     }
 #endif
 
-#ifdef buffertime
+#ifdef BUFFERTIME
     {
       int alsa_buffer_time = 500000; /* original 60 */
 
@@ -397,105 +401,150 @@ static int init(int rate_hz, int channels, int format, int flags)
 		snd_strerror(err));
 	    return(0);
 	}
-	printf("alsa-init: buffer_time: %d, period_time :%d\n",
-	    alsa_buffer_time, err);
+	if (verbose)
+	  printf("alsa-init: buffer_time: %d, period_time :%d\n",alsa_buffer_time, err);
     }
 #endif
 
+    /* get chunk-size */
+    if ((err = snd_pcm_hw_params_get_period_size(alsa_hwparams, 0)) < 0)
+      {
+	printf("alsa-init: unable to get chunk-size in hw-params: %s\n", snd_strerror(err));
+	return(0);
+      } else
+	{
+	  chunk_size = err;
+	  if (verbose) {printf("alsa-init: got chunksize %i\n", chunk_size);}
+	}
+
+    /* get buffer size */
+    if ((err = snd_pcm_hw_params_get_buffer_size(alsa_hwparams)) < 0)
+    {
+      printf("alsa-init: unable to get buffersize in hw-params: %s\n", snd_strerror(err));
+      return(0);
+    } else
+      {
+      ao_data.buffersize = err;
+      if (verbose) {printf("alsa-init: got buffersize %i\n", ao_data.buffersize);}
+      }
+    
+    if (MAX_OUTBURST > ao_data.buffersize) { //warning if MAX_OUTBURST is bigger than buffersize
+      printf("alsa-init: WARNING! MAX_OUTBURST exceeds your available buffersize.\nalsa-init: MAX_OUTBURST=%i, buffersize=%i\n",MAX_OUTBURST,ao_data.buffersize);}
+
+    if (chunk_size == ao_data.buffersize)
+      {
+      printf("alsa-init: Can't use period equal to buffer size (%u == %lu)", chunk_size, (long)buffer_size);
+      return(0);
+      }
+
+    /* finally install hardware parameters */
     if ((err = snd_pcm_hw_params(alsa_handler, alsa_hwparams)) < 0)
     {
-	printf("alsa-init: unable to set parameters: %s\n",
+	printf("alsa-init: unable to set hw-parameters: %s\n",
 	    snd_strerror(err));
 	return(0);
     }
+    // end setting hw-params
 
-#ifdef sw_params
+#ifdef SW_PARAMS
     {
-    chunk_size = snd_pcm_hw_params_get_period_size(alsa_hwparams, 0);
-    start_threshold = (double) ao_data.samplerate * start_delay / 1000000;
-    xfer_align = snd_pcm_sw_params_get_xfer_align(alsa_swparams);
+      size_t n;
+      xfer_align = snd_pcm_sw_params_get_xfer_align(alsa_swparams);
+      if (xfer_align == 0)
+	xfer_align = 4;
+      n = (ao_data.buffersize / xfer_align) * xfer_align;
+
+      if (start_delay <= 0) {
+	start_threshold = n + (double) ao_data.samplerate * start_delay / 1000000;
+      } else {
+	start_threshold = (double) ao_data.samplerate * start_delay / 1000000;
+      }
+      if (start_threshold < 1)
+	start_threshold = 1;
+      if (start_threshold > n)
+	start_threshold = n;
+
+      if (stop_delay <= 0) {
+	stop_threshold = ao_data.buffersize + (double) ao_data.samplerate * stop_delay / 1000000;
+      } else {
+	stop_threshold = (double) ao_data.samplerate * stop_delay / 1000000;
+      }
+
+      if (verbose) {
+	printf("alsa-init: start_threshold=%lu, stop_threshold=%lu\n",start_threshold,stop_threshold);
+	printf("alsa-init: n=%i\n", n);
+      }
 
     if ((err = snd_pcm_sw_params_current(alsa_handler, alsa_swparams)) < 0)
-    {
-	printf("alsa-init: unable to get parameters: %s\n",
-	    snd_strerror(err));
+      {
+	printf("alsa-init: unable to get parameters: %s\n",snd_strerror(err));
 	return(0);
-    }
+      }
+
+    //set min available frames to consider pcm ready (4)
+    if ((err = snd_pcm_sw_params_set_avail_min(alsa_handler, alsa_swparams, 4)) < 0)
+      {
+	printf("alsa-init: unable to set avail_min %s\n",snd_strerror(err));
+	return(0);
+      }
 	
-	if ((err = snd_pcm_sw_params_set_avail_min(alsa_handler, alsa_swparams, chunk_size)) < 0)
-	  {
-	    printf("alsa-init: unable to set avail_min %s\n",snd_strerror(err));
-	    return(0);
-	  }
+    if ((err = snd_pcm_sw_params_set_start_threshold(alsa_handler, alsa_swparams, start_threshold)) < 0)
+      {
+	printf("alsa-init: unable to set start_threshold %s\n",snd_strerror(err));
+	return(0);
+      }
 
+    if ((err = snd_pcm_sw_params_set_stop_threshold(alsa_handler, alsa_swparams, stop_threshold)) < 0)
+      {
+	printf("alsa-init: unable to set stop_threshold %s\n",snd_strerror(err));
+	return(0);
+      }
 
-	
-	if ((err = snd_pcm_sw_params_set_start_threshold(alsa_handler, alsa_swparams, start_threshold)) < 0)
-	  {
-	    printf("alsa-init: unable to set start_threshold %s\n",snd_strerror(err));
-	    return(0);
-	  }
-    } 
-    //      if ((err = snd_pcm_sw_params_set_xfer_align(alsa_handler, alsa_swparams, xfer_align)) < 0)
-    //{
-    //	printf("alsa-init: unable to set xfer_align: %s\n",
-    //	    snd_strerror(err));
-    //	return(0);
-    //}
-
-#ifdef set_start_mode
-    if ((err = snd_pcm_sw_params_set_start_mode(alsa_handler, alsa_swparams,
-	SND_PCM_START_DATA)) < 0)
-    {
-	printf("alsa-init: unable to set start mode: %s\n",
-	    snd_strerror(err));
+    //transfers stream aligned to 4 in nonblocking-mode it would be 1
+    if ((err = snd_pcm_sw_params_set_xfer_align(alsa_handler, alsa_swparams, 4)) < 0)
+      {
+	printf("alsa-init: unable to set xfer_align: %s\n",snd_strerror(err));
 	return(0);
-    }
-#endif
+      }
 
     if ((err = snd_pcm_sw_params(alsa_handler, alsa_swparams)) < 0)
-    {
-	printf("alsa-init: unable to set parameters: %s\n",
-	    snd_strerror(err));
+      {
+	printf("alsa-init: unable to install sw-params\n");
 	return(0);
+      }
+
+    bits_per_sample = snd_pcm_format_physical_width(alsa_format);
+    bits_per_frame = bits_per_sample * channels;
+    chunk_bytes = chunk_size * bits_per_frame / 8;
+
+    if (verbose) {
+      printf("alsa-init: bits per sample (bps)=%i, bits per frame (bpf)=%i, chunk_bytes=%i\n",bits_per_sample,bits_per_frame,chunk_bytes);}
     }
 
-//    snd_pcm_sw_params_default(alsa_handler, alsa_swparams);
-#endif
+#endif //end swparams
+
     if ((err = snd_pcm_prepare(alsa_handler)) < 0)
     {
 	printf("alsa-init: pcm prepare error: %s\n", snd_strerror(err));
 	return(0);
     }
 
-#ifdef start
-    if ((err = snd_pcm_start(alsa_handler)) < 0)
-    {
-	printf("alsa-init: pcm start error: %s\n", snd_strerror(err));
-	if (err != -EPIPE)
-	    return(0);
-	if ((err = snd_pcm_start(alsa_handler)) < 0)
-	{
-	    printf("alsa-init: pcm start error: %s\n", snd_strerror(err));
-		return(0);
-	}
-    }
-#endif
-    printf("AUDIO: %d Hz/%d channels/%d bpf/%d bytes buffer/%s\n",
+    printf("alsa9: %d Hz/%d channels/%d bpf/%d bytes buffer/%s\n",
 	ao_data.samplerate, ao_data.channels, ao_data.bps, ao_data.buffersize,
 	snd_pcm_format_description(alsa_format));
     return(1);
-}
+} // end init
+
 
 /* close audio device */
 static void uninit()
 {
     int err;
 
-    if (alsa_device != NULL)
-	free(alsa_device);
+    //if (alsa_device != NULL)
+    //free(alsa_device);
 
-    snd_pcm_hw_params_free(alsa_hwparams);
+    //snd_pcm_hw_params_free(alsa_hwparams);
 
     if ((err = snd_pcm_drain(alsa_handler)) < 0)
     {
@@ -503,19 +552,16 @@ static void uninit()
 	return;
     }
 
-#ifdef start
-    if ((err = snd_pcm_reset(alsa_handler)) < 0)
-    {
-	printf("alsa-uninit: pcm reset error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
-
     if ((err = snd_pcm_close(alsa_handler)) < 0)
     {
 	printf("alsa-uninit: pcm close error: %s\n", snd_strerror(err));
 	return;
     }
+    else {
+      alsa_handler = NULL;
+      alsa_device = NULL;
+      printf("alsa-uninit: pcm closed\n");
+    }
 }
 
 static void audio_pause()
@@ -546,14 +592,6 @@ static void audio_resume()
 	printf("alsa-resume: pcm prepare error: %s\n", snd_strerror(err));
 	return;
     }
-
-#ifdef start
-    if ((err = snd_pcm_start(alsa_handler)) < 0)
-    {
-	printf("alsa-resume: pcm start error: %s\n", snd_strerror(err));
-	return;
-    }
-#endif
 }