strawberry-audio-player-windows-mac-linux/src/engine/xinescope.c

/* Author: Max Howell <max.howell@methylblue.com>, (C) 2004
   Copyright: See COPYING file that comes with this distribution

   This has to be a c file or for some reason it won't link! (GCC 3.4.1)

*/

/* need access to port_ticket */
#ifndef XINE_ENGINE_INTERNAL
#  define XINE_ENGINE_INTERNAL
#endif

#include "config.h"

#include "xinescope.h"
#include <xine/post.h>
#include <xine/xine_internal.h>

typedef struct scope_plugin_s scope_plugin_t;

struct scope_plugin_s {
  post_plugin_t post;

  metronom_t metronom;
  int channels;
  MyNode *list;
};

/*************************
 * post plugin functions *
 *************************/

static int scope_port_open(xine_audio_port_t *port_gen, xine_stream_t *stream, uint32_t bits, uint32_t rate, int mode) {

  #define port ((post_audio_port_t*)port_gen)
  #define this ((scope_plugin_t*)((post_audio_port_t*)port_gen)->post)

  _x_post_rewire((post_plugin_t*)port->post);
  _x_post_inc_usage(port);

  port->stream = stream;
  port->bits = bits;
  port->rate = rate;
  port->mode = mode;

  this->channels = _x_ao_mode2channels(mode);

  return port->original_port->open(port->original_port, stream, bits, rate, mode);
}

static void scope_port_close(xine_audio_port_t *port_gen, xine_stream_t *stream) {

  MyNode *node;

  /* ensure the buffers are deleted during the next XineEngine::timerEvent() */
  for(node = this->list->next; node != this->list; node = node->next)
    node->vpts = node->vpts_end = -1;

  port->stream = NULL;
  port->original_port->close(port->original_port, stream);

  _x_post_dec_usage(port);
}

static void scope_port_put_buffer(xine_audio_port_t *port_gen, audio_buffer_t *buf, xine_stream_t *stream) {
/* FIXME With 8-bit samples the scope won't work correctly. For a special 8-bit code path, the sample size could be checked like this: if(port->bits == 8) */

  const int num_samples = buf->num_frames * this->channels;
  metronom_t *myMetronom = &this->metronom;
  MyNode *new_node;

  /* I keep my own metronom because xine wouldn't for some reason */
  memcpy(&this->metronom, stream->metronom, sizeof(metronom_t));

  new_node = (MyNode *) malloc(sizeof(MyNode));
  new_node->vpts = myMetronom->got_audio_samples(myMetronom, buf->vpts, buf->num_frames);
  new_node->num_frames = buf->num_frames;
  new_node->mem = (int16_t *) malloc(num_samples * 2);
  memcpy(new_node->mem, buf->mem, num_samples * 2);

  {
    int64_t
    K  = 32768; /*smpls = 1<<16 samples*/
    K *= num_samples;
    K /= (1<<16);
    K += new_node->vpts;

    new_node->vpts_end = K;
  }

  port->original_port->put_buffer(port->original_port, buf, stream);

  /* Finally we should append the current buffer to the list
   * This is thread-safe due to the way we handle the list in the GUI thread */
  new_node->next   = this->list->next;
  this->list->next = new_node;

  #undef port
  #undef this
}

static void scope_dispose(post_plugin_t *post) {

  MyNode *list = ((scope_plugin_t*)post)->list;
  MyNode *prev;
  MyNode *node = list;

  /* Free all elements of the list (a ring buffer) */
  do {
    prev = node->next;

    free(node->mem);
    free(node);

    node = prev;
  }
  while(node != list);


  free(post);
}


/************************
 * plugin init function *
 ************************/

xine_post_t *scope_plugin_new(xine_t *xine, xine_audio_port_t *audio_target) {

  scope_plugin_t *scope_plugin = (scope_plugin_t *) calloc(1, sizeof(scope_plugin_t));
  post_plugin_t *post_plugin = (post_plugin_t *)scope_plugin;

  {
    post_in_t *input;
    post_out_t *output;
    post_audio_port_t *port;

    _x_post_init(post_plugin, 1, 0);

    port = _x_post_intercept_audio_port(post_plugin, audio_target, &input, &output);
    port->new_port.open = scope_port_open;
    port->new_port.close = scope_port_close;
    port->new_port.put_buffer = scope_port_put_buffer;

    post_plugin->xine_post.audio_input[0] = &port->new_port;
    post_plugin->xine_post.type = PLUGIN_POST;

    post_plugin->dispose = scope_dispose;
  }

  // code is straight from xine_init_post() can't use that function as it only dlopens the plugins and our plugin is statically linked in

  post_plugin->running_ticket = xine->port_ticket;
  post_plugin->xine = xine;

  /* scope_plugin_t init */
  scope_plugin->list = (MyNode *) calloc(1, sizeof(MyNode));
  scope_plugin->list->next = scope_plugin->list;

  return &post_plugin->xine_post;
}

MyNode *scope_plugin_list(void *post) {
  return ((scope_plugin_t*)post)->list;
}

int scope_plugin_channels(void *post) {
  return ((scope_plugin_t*)post)->channels;
}

metronom_t* scope_plugin_metronom(void *post) {
  return &((scope_plugin_t*)post)->metronom;
}