vm.c

linux下的MPEG1

     - some kind of jump (Jump(TT/SS/VTS_TTN/CallSS/link C/PG/PGC/PTTN)
     - just play video i.e first PG
       (This is what happens if you fall of the end of the pre_cmds)
     - or an error (are there more cases?) */
  if((vm->state).pgc->command_tbl && (vm->state).pgc->command_tbl->nr_of_pre) {
    if(vmEval_CMD((vm->state).pgc->command_tbl->pre_cmds, 
		  (vm->state).pgc->command_tbl->nr_of_pre, 
		  &(vm->state).registers, &link_values)) {
      /*  link_values contains the 'jump' return value */
      return link_values;
    } else {
#ifdef TRACE
      fprintf(MSG_OUT, "libdvdnav: PGC pre commands didn't do a Jump, Link or Call\n");
#endif
    }
  }
  return play_PG(vm);
}  

static link_t play_PGC_PG(vm_t *vm, int pgN) {    
  link_t link_values;
  
#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: play_PGC_PG:");
  if((vm->state).domain != FP_DOMAIN) {
    fprintf(MSG_OUT, " (vm->state).pgcN (%i)\n", get_PGCN(vm));
  } else {
    fprintf(MSG_OUT, " first_play_pgc\n");
  }
#endif

  /*  This must be set before the pre-commands are executed because they
   *  might contain a CallSS that will save resume state */

  /* FIXME: This may be only a temporary fix for something... */
  (vm->state).pgN = pgN;
  (vm->state).cellN = 0;
  (vm->state).blockN = 0;

  /* eval -> updates the state and returns either 
     - some kind of jump (Jump(TT/SS/VTS_TTN/CallSS/link C/PG/PGC/PTTN)
     - just play video i.e first PG
       (This is what happens if you fall of the end of the pre_cmds)
     - or an error (are there more cases?) */
  if((vm->state).pgc->command_tbl && (vm->state).pgc->command_tbl->nr_of_pre) {
    if(vmEval_CMD((vm->state).pgc->command_tbl->pre_cmds, 
		  (vm->state).pgc->command_tbl->nr_of_pre, 
		  &(vm->state).registers, &link_values)) {
      /*  link_values contains the 'jump' return value */
      return link_values;
    } else {
#ifdef TRACE
      fprintf(MSG_OUT, "libdvdnav: PGC pre commands didn't do a Jump, Link or Call\n");
#endif
    }
  }
  return play_PG(vm);
}  

static link_t play_PGC_post(vm_t *vm) {
  link_t link_values;

#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: play_PGC_post:\n");
#endif
  
  /* eval -> updates the state and returns either 
     - some kind of jump (Jump(TT/SS/VTS_TTN/CallSS/link C/PG/PGC/PTTN)
     - just go to next PGC
       (This is what happens if you fall of the end of the post_cmds)
     - or an error (are there more cases?) */
  if((vm->state).pgc->command_tbl && (vm->state).pgc->command_tbl->nr_of_post &&
     vmEval_CMD((vm->state).pgc->command_tbl->post_cmds,
		(vm->state).pgc->command_tbl->nr_of_post, 
		&(vm->state).registers, &link_values)) {
    return link_values;
  }
  
#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: ** Fell of the end of the pgc, continuing in NextPGC\n");
#endif
  /* Should end up in the STOP_DOMAIN if next_pgc is 0. */
  if(!set_PGCN(vm, (vm->state).pgc->next_pgc_nr)) {
    link_values.command = Exit;
    return link_values;
  }
  return play_PGC(vm);
}

static link_t play_PG(vm_t *vm) {
#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: play_PG: (vm->state).pgN (%i)\n", (vm->state).pgN);
#endif
  
  assert((vm->state).pgN > 0);
  if((vm->state).pgN > (vm->state).pgc->nr_of_programs) {
#ifdef TRACE
    fprintf(MSG_OUT, "libdvdnav: play_PG: (vm->state).pgN (%i) > pgc->nr_of_programs (%i)\n", 
	    (vm->state).pgN, (vm->state).pgc->nr_of_programs );
#endif
    assert((vm->state).pgN == (vm->state).pgc->nr_of_programs + 1); 
    return play_PGC_post(vm);
  }
  
  (vm->state).cellN = (vm->state).pgc->program_map[(vm->state).pgN - 1];
  
  return play_Cell(vm);
}

static link_t play_Cell(vm_t *vm) {
  static const link_t play_this = {PlayThis, /* Block in Cell */ 0, 0, 0};

#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: play_Cell: (vm->state).cellN (%i)\n", (vm->state).cellN);
#endif
  
  assert((vm->state).cellN > 0);
  if((vm->state).cellN > (vm->state).pgc->nr_of_cells) {
#ifdef TRACE
    fprintf(MSG_OUT, "libdvdnav: (vm->state).cellN (%i) > pgc->nr_of_cells (%i)\n", 
	    (vm->state).cellN, (vm->state).pgc->nr_of_cells );
#endif
    assert((vm->state).cellN == (vm->state).pgc->nr_of_cells + 1); 
    return play_PGC_post(vm);
  }
  
  /* Multi angle/Interleaved */
  switch((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode) {
  case 0: /*  Normal */
    assert((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type == 0);
    break;
  case 1: /*  The first cell in the block */
    switch((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type) {
    case 0: /*  Not part of a block */
      assert(0);
      break;
    case 1: /*  Angle block */
      /* Loop and check each cell instead? So we don't get outside the block? */
      (vm->state).cellN += (vm->state).AGL_REG - 1;
#ifdef STRICT
      assert((vm->state).cellN <= (vm->state).pgc->nr_of_cells);
      assert((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode != 0);
      assert((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type == 1);
#else
      if (!((vm->state).cellN <= (vm->state).pgc->nr_of_cells) ||
          !((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode != 0) ||
	  !((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type == 1)) {
	fprintf(MSG_OUT, "libdvdnav: Invalid angle block\n");
	(vm->state).cellN -= (vm->state).AGL_REG - 1;
      }
#endif
      break;
    case 2: /*  ?? */
    case 3: /*  ?? */
    default:
      fprintf(MSG_OUT, "libdvdnav: Invalid? Cell block_mode (%d), block_type (%d)\n",
	      (vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode,
	      (vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type);
      assert(0);
    }
    break;
  case 2: /*  Cell in the block */
  case 3: /*  Last cell in the block */
  /* These might perhaps happen for RSM or LinkC commands? */
  default:
    fprintf(MSG_OUT, "libdvdnav: Cell is in block but did not enter at first cell!\n");
  }
  
  /* Updates (vm->state).pgN and PTTN_REG */
  if(!set_PGN(vm)) {
    /* Should not happen */
    assert(0);
    return play_PGC_post(vm);
  }
  (vm->state).cell_restart++;
  (vm->state).blockN = 0;
#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: Cell should restart here\n");
#endif
  return play_this;
}

static link_t play_Cell_post(vm_t *vm) {
  cell_playback_t *cell;
  
#ifdef TRACE
  fprintf(MSG_OUT, "libdvdnav: play_Cell_post: (vm->state).cellN (%i)\n", (vm->state).cellN);
#endif
  
  cell = &(vm->state).pgc->cell_playback[(vm->state).cellN - 1];
  
  /* Still time is already taken care of before we get called. */
  
  /* Deal with a Cell command, if any */
  if(cell->cell_cmd_nr != 0) {
    link_t link_values;
    
/*  These asserts are now not needed.
 *  Some DVDs have no cell commands listed in the PGC,
 *  but the Cell itself points to a cell command that does not exist.
 *  For this situation, just ignore the cell command and continue.
 *
 *  assert((vm->state).pgc->command_tbl != NULL);
 *  assert((vm->state).pgc->command_tbl->nr_of_cell >= cell->cell_cmd_nr);
 */

    if ((vm->state).pgc->command_tbl != NULL &&
        (vm->state).pgc->command_tbl->nr_of_cell >= cell->cell_cmd_nr) {
#ifdef TRACE
      fprintf(MSG_OUT, "libdvdnav: Cell command present, executing\n");
#endif
      if(vmEval_CMD(&(vm->state).pgc->command_tbl->cell_cmds[cell->cell_cmd_nr - 1], 1,
		    &(vm->state).registers, &link_values)) {
        return link_values;
      } else {
#ifdef TRACE
        fprintf(MSG_OUT, "libdvdnav: Cell command didn't do a Jump, Link or Call\n");
#endif
      }
    } else {
#ifdef TRACE
      fprintf(MSG_OUT, "libdvdnav: Invalid Cell command\n");
#endif
    }
  }
  
  /* Where to continue after playing the cell... */
  /* Multi angle/Interleaved */
  switch((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode) {
  case 0: /*  Normal */
    assert((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type == 0);
    (vm->state).cellN++;
    break;
  case 1: /*  The first cell in the block */
  case 2: /*  A cell in the block */
  case 3: /*  The last cell in the block */
  default:
    switch((vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type) {
    case 0: /*  Not part of a block */
      assert(0);
      break;
    case 1: /*  Angle block */
      /* Skip the 'other' angles */
      (vm->state).cellN++;
      while((vm->state).cellN <= (vm->state).pgc->nr_of_cells &&
	    (vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode >= 2) {
	(vm->state).cellN++;
      }
      break;
    case 2: /*  ?? */
    case 3: /*  ?? */
    default:
      fprintf(MSG_OUT, "libdvdnav: Invalid? Cell block_mode (%d), block_type (%d)\n",
	      (vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_mode,
	      (vm->state).pgc->cell_playback[(vm->state).cellN - 1].block_type);
      assert(0);
    }
    break;
  }
  
  /* Figure out the correct pgN for the new cell */ 
  if(!set_PGN(vm)) {
#ifdef TRACE
    fprintf(MSG_OUT, "libdvdnav: last cell in this PGC\n");
#endif
    return play_PGC_post(vm);
  }
  return play_Cell(vm);
}


/* link processing */

static int process_command(vm_t *vm, link_t link_values) {
  
  while(link_values.command != PlayThis) {
    
#ifdef TRACE
    fprintf(MSG_OUT, "libdvdnav: Before printout starts:\n");
    vm_print_link(link_values);
    fprintf(MSG_OUT, "libdvdnav: Link values %i %i %i %i\n", link_values.command, 
	    link_values.data1, link_values.data2, link_values.data3);
    vm_print_current_domain_state(vm);
    fprintf(MSG_OUT, "libdvdnav: Before printout ends.\n");
#endif
    
    switch(link_values.command) {
    case LinkNoLink:
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      return 0;  /* no actual jump */

    case LinkTopC:
      /* Restart playing from the beginning of the current Cell. */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      link_values = play_Cell(vm);
      break;
    case LinkNextC:
      /* Link to Next Cell */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      (vm->state).cellN += 1;
      link_values = play_Cell(vm);
      break;
    case LinkPrevC:
      /* Link to Previous Cell */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      assert((vm->state).cellN > 1);
      (vm->state).cellN -= 1;
      link_values = play_Cell(vm);
      break;
      
    case LinkTopPG:
      /* Link to Top of current Program */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      link_values = play_PG(vm);
      break;
    case LinkNextPG:
      /* Link to Next Program */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      (vm->state).pgN += 1;
      link_values = play_PG(vm);
      break;
    case LinkPrevPG:
      /* Link to Previous Program */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      assert((vm->state).pgN > 1);
      (vm->state).pgN -= 1;
      link_values = play_PG(vm);
      break;

    case LinkTopPGC:
      /* Restart playing from beginning of current Program Chain */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      link_values = play_PGC(vm);
      break;
    case LinkNextPGC:
      /* Link to Next Program Chain */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      assert((vm->state).pgc->next_pgc_nr != 0);
      if(set_PGCN(vm, (vm->state).pgc->next_pgc_nr))
	link_values = play_PGC(vm);
      else
	link_values.command = Exit;
      break;
    case LinkPrevPGC:
      /* Link to Previous Program Chain */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      assert((vm->state).pgc->prev_pgc_nr != 0);
      if(set_PGCN(vm, (vm->state).pgc->prev_pgc_nr))
	link_values = play_PGC(vm);
      else
	link_values.command = Exit;
      break;
    case LinkGoUpPGC:
      /* Link to GoUp Program Chain */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      assert((vm->state).pgc->goup_pgc_nr != 0);
      if(set_PGCN(vm, (vm->state).pgc->goup_pgc_nr))
	link_values = play_PGC(vm);
      else
	link_values.command = Exit;
      break;
    case LinkTailPGC:
      /* Link to Tail of Program Chain */
      /* BUTTON number:data1 */
      if(link_values.data1 != 0)
	(vm->state).HL_BTNN_REG = link_values.data1 << 10;
      link_values = play_PGC_post(vm);
    break;

    case LinkRSM:
      {
	/* Link to Resume point */
	int i;
	
	/* Check and see if there is any rsm info!! */
	if (!(vm->state).rsm_vtsN) {
	  fprintf(MSG_OUT, "libdvdnav: trying to resume without any resume info set\n");
	  link_values.command = Exit;
	  break;
	}
	
	(vm->state).domain = VTS_DOMAIN;
	if (!ifoOpenNewVTSI(vm, vm->dvd, (vm->state).rsm_vtsN))
	  assert(0);
	set_PGCN(vm, (vm->state).rsm_pgcN);
	
	/* These should never be set in SystemSpace and/or MenuSpace */ 
	/* (vm->state).TTN_REG = rsm_tt; ?? */
	/* (vm->state).TT_PGCN_REG = (vm->state).rsm_pgcN; ?? */
	for(i = 0; i < 5; i++) {
	  (vm->state).registers.SPRM[4 + i] = (vm->state).rsm_regs[i];
	}
	
	if(link_values.data1 != 0)
	  (vm->state).HL_BTNN_REG = link_values.data1 << 10;
	
	if((vm->state).rsm_cellN == 0) {
	  assert((vm->state).cellN); /*  Checking if this ever happens */
	  (vm->state).pgN = 1;
	  link_values = play_PG(vm);
	} else { 
	  /* (vm->state).pgN = ?? this gets the right value in set_PGN() below */
	  (vm->state).cellN = (vm->state).rsm_cellN;
	  link_values.command = PlayThis;
	  link_values.data1 = (vm->state).rsm_blockN & 0xffff;
	  link_values.data2 = (vm->state).rsm_blockN >> 16;
	  if(!set_PGN(vm)) {
	    /* Were at the end of the PGC, should not happen for a RSM */
	    assert(0);
	    link_values.command = LinkTailPGC;
	    link_values.data1 = 0;  /* No button */
	  }
	}
      }
      break;
    case LinkPGCN:
      /* Link to Program Chain Number:data1 */
      if(!set_PGCN(vm, link_values.data1))
	assert(0);
      link_values = play_PGC(vm);
      break;
    case LinkPTTN:
      /* Link to Part of current Title Number:data1 */
      /* BUTTON number:data2 */
      /* PGC Pre-Commands are not executed */
      assert((vm->state).domain == VTS_DOMAIN);
      if(link_values.data2 != 0)
	(vm->state).HL_BTNN_REG = link_values.data2 << 10;
      if(!set_VTS_PTT(vm, (vm->state).vtsN, (vm->state).VTS_TTN_REG, link_values.data1))
	assert(0);
      link_values = play_PG(vm);
      break;
    case LinkPGN:
      /* Link to Program Number:data1 */
      /* BUTTON number:data2 */
      if(link_values.data2 != 0)
	(vm->state).HL_BTNN_REG = link_values.data2 << 10;
      /* Update any other state, PTTN perhaps? */
      (vm->state).pgN = link_values.data1;
      link_values = play_PG(vm);
      break;
    case LinkCN:
      /* Link to Cell Number:data1 */