path: root/doc/demux_nsf.c

/*
 * Copyright Copyright (C) 2000-2002 the xine project
 *
 * This file is part of xine, a free video player.
 *
 * xine is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * xine is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 *
 * NSF File "Demuxer" by Mike Melanson (melanson@pcisys.net)
 * This is really just a loader for NES Music File Format (extension NSF)
 * which loads an entire NSF file and passes it over to the NSF audio
 * decoder.
 *
 * After the file is sent over, the demuxer controls the playback by
 * sending empty buffers with incrementing pts values.
 *
 * For more information regarding the NSF format, visit:
 *   http://www.tripoint.org/kevtris/nes/nsfspec.txt
 *
 * $Id: demux_nsf.c,v 1.1 2003/04/03 14:51:25 grothoff Exp $
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>

#include "xine_internal.h"
#include "xineutils.h"
#include "compat.h"
#include "demux.h"
#include "bswap.h"

#define NSF_HEADER_SIZE 0x80
#define NSF_SAMPLERATE 44100
#define NSF_BITS 8
#define NSF_CHANNELS 1
#define NSF_REFRESH_RATE 60
#define NSF_PTS_INC (90000 / NSF_REFRESH_RATE)

typedef struct
{

  demux_plugin_t demux_plugin;

  xine_stream_t *stream;

  config_values_t *config;

  fifo_buffer_t *video_fifo;
  fifo_buffer_t *audio_fifo;

  input_plugin_t *input;

  pthread_t thread;
  int thread_running;
  pthread_mutex_t mutex;
  int send_end_buffers;

  int status;

  char *title;
  char *artist;
  char *copyright;
  int total_songs;
  int current_song;
  int new_song;                 /* indicates song change */
  off_t filesize;

  int64_t current_pts;
  int file_sent;

  char last_mrl[1024];

} demux_nsf_t;

typedef struct
{

  demux_class_t demux_class;

  /* class-wide, global variables here */

  xine_t *xine;
  config_values_t *config;
} demux_nsf_class_t;


/* returns 1 if the NSF file was opened successfully, 0 otherwise */
static int
open_nsf_file (demux_nsf_t * this)
{

  unsigned char header[NSF_HEADER_SIZE];

  this->input->seek (this->input, 0, SEEK_SET);
  if (this->input->read (this->input, header, NSF_HEADER_SIZE) !=
      NSF_HEADER_SIZE)
    return 0;

  /* check for the signature */
  if ((header[0] != 'N') ||
      (header[1] != 'E') ||
      (header[2] != 'S') || (header[3] != 'M') || (header[4] != 0x1A))
    return 0;

  this->total_songs = header[6];
  this->current_song = header[7];
  this->title = strdup (&header[0x0E]);
  this->artist = strdup (&header[0x2E]);
  this->copyright = strdup (&header[0x4E]);

  this->filesize = this->input->get_length (this->input);

  return 1;
}

static int
demux_nsf_send_chunk (demux_plugin_t * this_gen)
{

  demux_nsf_t *this = (demux_nsf_t *) this_gen;
  buf_element_t *buf;
  int bytes_read;
  char title[100];

  /* send chunks of the file to the decoder until file is completely
   * loaded; then send control buffers */
  if (!this->file_sent)
    {
      buf = this->audio_fifo->buffer_pool_alloc (this->audio_fifo);
      buf->type = BUF_AUDIO_NSF;
      bytes_read =
        this->input->read (this->input, buf->content, buf->max_size);

      if (bytes_read == 0)
        {
          /* the file has been completely loaded, free the buffer and start
           * sending control buffers */
          buf->free_buffer (buf);
          this->file_sent = 1;

        }
      else
        {

          /* keep loading the file */
          if (bytes_read < buf->max_size)
            buf->size = bytes_read;
          else
            buf->size = buf->max_size;

          buf->extra_info->input_pos = 0;
          buf->extra_info->input_length = 0;
          buf->extra_info->input_time = 0;
          buf->pts = 0;

          this->audio_fifo->put (this->audio_fifo, buf);
        }
    }

  /* this is not an 'else' because control might fall through from above */
  if (this->file_sent)
    {
      /* send a control buffer */
      buf = this->audio_fifo->buffer_pool_alloc (this->audio_fifo);

      if (this->new_song)
        {

          buf->decoder_info[1] = this->current_song;
          this->new_song = 0;
          sprintf (title, "%s, song %d/%d",
                   this->title, this->current_song, this->total_songs);
          if (this->stream->meta_info[XINE_META_INFO_TITLE])
            free (this->stream->meta_info[XINE_META_INFO_TITLE]);
          this->stream->meta_info[XINE_META_INFO_TITLE] = strdup (title);
          xine_demux_control_newpts (this->stream, this->current_pts, 0);

        }
      else
        buf->decoder_info[1] = 0;

      buf->type = BUF_AUDIO_NSF;
      buf->extra_info->input_pos = this->current_song - 1;
      buf->extra_info->input_length = this->total_songs;
      buf->extra_info->input_time = this->current_pts / 90;
      buf->pts = this->current_pts;
      buf->size = 0;
      this->audio_fifo->put (this->audio_fifo, buf);

      this->current_pts += NSF_PTS_INC;
    }

  return this->status;
}

static void
demux_nsf_send_headers (demux_plugin_t * this_gen)
{

  demux_nsf_t *this = (demux_nsf_t *) this_gen;
  buf_element_t *buf;
  char copyright[100];

  this->video_fifo = this->stream->video_fifo;
  this->audio_fifo = this->stream->audio_fifo;

  this->status = DEMUX_OK;

  /* load stream information */
  this->stream->stream_info[XINE_STREAM_INFO_HAS_VIDEO] = 0;
  this->stream->stream_info[XINE_STREAM_INFO_HAS_AUDIO] = 1;
  this->stream->stream_info[XINE_STREAM_INFO_AUDIO_CHANNELS] = NSF_CHANNELS;
  this->stream->stream_info[XINE_STREAM_INFO_AUDIO_SAMPLERATE] =
    NSF_SAMPLERATE;
  this->stream->stream_info[XINE_STREAM_INFO_AUDIO_BITS] = NSF_BITS;

  this->stream->meta_info[XINE_META_INFO_TITLE] = strdup (this->title);
  this->stream->meta_info[XINE_META_INFO_ARTIST] = strdup (this->artist);
  sprintf (copyright, "Copyright (C) %s", this->copyright);
  this->stream->meta_info[XINE_META_INFO_COMMENT] = strdup (copyright);

  /* send start buffers */
  xine_demux_control_start (this->stream);

  /* send init info to the audio decoder */
  if (this->audio_fifo)
    {
      buf = this->audio_fifo->buffer_pool_alloc (this->audio_fifo);
      buf->type = BUF_AUDIO_NSF;
      buf->decoder_flags = BUF_FLAG_HEADER;
      buf->decoder_info[0] = 5;
      buf->decoder_info[1] = NSF_SAMPLERATE;
      buf->decoder_info[2] = NSF_BITS;
      buf->decoder_info[3] = NSF_CHANNELS;

      /* send the NSF filesize in the body, big endian format */
      buf->content[0] = (this->filesize >> 24) & 0xFF;
      buf->content[1] = (this->filesize >> 16) & 0xFF;
      buf->content[2] = (this->filesize >> 8) & 0xFF;
      buf->content[3] = (this->filesize >> 0) & 0xFF;
      /* send the requested song */
      buf->content[4] = this->current_song + 5;

      this->audio_fifo->put (this->audio_fifo, buf);
    }
}

static int
demux_nsf_seek (demux_plugin_t * this_gen, off_t start_pos, int start_time)
{

  demux_nsf_t *this = (demux_nsf_t *) this_gen;

  /* if thread is not running, initialize demuxer */
  if (!this->stream->demux_thread_running)
    {

      /* send new pts */
      xine_demux_control_newpts (this->stream, 0, 0);

      this->status = DEMUX_OK;

      /* reposition stream at the start for loading */
      this->input->seek (this->input, 0, SEEK_SET);

      this->file_sent = 0;
      this->current_pts = 0;
      this->new_song = 1;
    }
  else
    {
      this->current_song = start_pos + 1;
      this->new_song = 1;
      this->current_pts = 0;
      xine_demux_flush_engine (this->stream);
    }

  return this->status;
}

static void
demux_nsf_dispose (demux_plugin_t * this_gen)
{
  demux_nsf_t *this = (demux_nsf_t *) this_gen;

  free (this->title);
  free (this->artist);
  free (this->copyright);
  free (this);
}

static int
demux_nsf_get_status (demux_plugin_t * this_gen)
{
  demux_nsf_t *this = (demux_nsf_t *) this_gen;

  return this->status;
}

/* return the approximate length in miliseconds */
static int
demux_nsf_get_stream_length (demux_plugin_t * this_gen)
{

  return 0;
}

static uint32_t
demux_nsf_get_capabilities (demux_plugin_t * this_gen)
{
  return DEMUX_CAP_NOCAP;
}

static int
demux_nsf_get_optional_data (demux_plugin_t * this_gen,
                             void *data, int data_type)
{
  return DEMUX_OPTIONAL_UNSUPPORTED;
}

static demux_plugin_t *
open_plugin (demux_class_t * class_gen, xine_stream_t * stream,
             input_plugin_t * input_gen)
{

  input_plugin_t *input = (input_plugin_t *) input_gen;
  demux_nsf_t *this;

  if (!(input->get_capabilities (input) & INPUT_CAP_SEEKABLE))
    {
      if (stream->xine->verbosity >= XINE_VERBOSITY_DEBUG)
        printf (_("demux_nsf.c: input not seekable, can not handle!\n"));
      return NULL;
    }

  this = xine_xmalloc (sizeof (demux_nsf_t));
  this->stream = stream;
  this->input = input;

  this->demux_plugin.send_headers = demux_nsf_send_headers;
  this->demux_plugin.send_chunk = demux_nsf_send_chunk;
  this->demux_plugin.seek = demux_nsf_seek;
  this->demux_plugin.dispose = demux_nsf_dispose;
  this->demux_plugin.get_status = demux_nsf_get_status;
  this->demux_plugin.get_stream_length = demux_nsf_get_stream_length;
  this->demux_plugin.get_video_frame = NULL;
  this->demux_plugin.got_video_frame_cb = NULL;
  this->demux_plugin.get_capabilities = demux_nsf_get_capabilities;
  this->demux_plugin.get_optional_data = demux_nsf_get_optional_data;
  this->demux_plugin.demux_class = class_gen;

  this->status = DEMUX_FINISHED;

  switch (stream->content_detection_method)
    {

    case METHOD_BY_CONTENT:
    case METHOD_EXPLICIT:

      if (!open_nsf_file (this))
        {
          free (this);
          return NULL;
        }

      break;

    case METHOD_BY_EXTENSION:
      {
        char *ending, *mrl;

        mrl = input->get_mrl (input);

        ending = strrchr (mrl, '.');

        if (!ending)
          {
            free (this);
            return NULL;
          }

        if (strncasecmp (ending, ".nsf", 4))
          {
            free (this);
            return NULL;
          }

        if (!open_nsf_file (this))
          {
            free (this);
            return NULL;
          }

      }

      break;

    default:
      free (this);
      return NULL;
    }

  strncpy (this->last_mrl, input->get_mrl (input), 1024);

  return &this->demux_plugin;
}

static char *
get_description (demux_class_t * this_gen)
{
  return "NES Music file demux plugin";
}

static char *
get_identifier (demux_class_t * this_gen)
{
  return "NSF";
}

static char *
get_extensions (demux_class_t * this_gen)
{
  return "nsf";
}

static char *
get_mimetypes (demux_class_t * this_gen)
{
  return NULL;
}

static void
class_dispose (demux_class_t * this_gen)
{

  demux_nsf_class_t *this = (demux_nsf_class_t *) this_gen;

  free (this);
}

void *
demux_nsf_init_plugin (xine_t * xine, void *data)
{

  demux_nsf_class_t *this;

  this = xine_xmalloc (sizeof (demux_nsf_class_t));
  this->config = xine->config;
  this->xine = xine;

  this->demux_class.open_plugin = open_plugin;
  this->demux_class.get_description = get_description;
  this->demux_class.get_identifier = get_identifier;
  this->demux_class.get_mimetypes = get_mimetypes;
  this->demux_class.get_extensions = get_extensions;
  this->demux_class.dispose = class_dispose;

  return this;
}