Bochs/bochs/gui/siminterface.cc

/////////////////////////////////////////////////////////////////////////
// $Id: siminterface.cc,v 1.70 2002-10-01 13:40:05 bdenney Exp $
/////////////////////////////////////////////////////////////////////////
//
// See siminterface.h for description of the siminterface concept.
// Basically, the siminterface is visible from both the simulator and
// the configuration user interface, and allows them to talk to each other.

#include "bochs.h"

bx_simulator_interface_c *SIM = NULL;
logfunctions *siminterface_log = NULL;
#define LOG_THIS siminterface_log->

// bx_simulator_interface just defines the interface that the Bochs simulator
// and the gui will use to talk to each other.  None of the methods of
// bx_simulator_interface are implemented; they are all virtual.  The
// bx_real_sim_c class is a child of bx_simulator_interface_c, and it
// implements all the methods.  The idea is that a gui needs to know only
// definition of bx_simulator_interface to talk to Bochs.  The gui should
// not need to include bochs.h.  
//
// I made this separation to ensure that all guis use the siminterface to do
// access bochs internals, instead of accessing things like
// bx_keyboard.s.internal_buffer[4] (or whatever) directly. -Bryce
// 

class bx_real_sim_c : public bx_simulator_interface_c {
  sim_interface_callback_t callback;
  void *callback_ptr;
  int init_done;
  bx_param_c **param_registry;
  int registry_alloc_size;
  int enabled;
  // save context to jump to if we must quit unexpectedly
  jmp_buf *quit_context;
public:
  bx_real_sim_c ();
  virtual ~bx_real_sim_c ();
  virtual void set_quit_context (jmp_buf *context) { quit_context = context; }
  virtual int get_init_done () { return init_done; }
  virtual int set_init_done (int n) { init_done = n; return 0;}
  virtual void get_param_id_range (int *min, int *max) {
    *min = BXP_NULL;
    *max = BXP_THIS_IS_THE_LAST-1;
  }
  virtual int register_param (bx_id id, bx_param_c *it);
  virtual void reset_all_param ();
  virtual bx_param_c *get_param (bx_id id);
  virtual bx_param_num_c *get_param_num (bx_id id);
  virtual bx_param_string_c *get_param_string (bx_id id);
  virtual bx_param_bool_c *get_param_bool (bx_id id);
  virtual bx_param_enum_c *get_param_enum (bx_id id);
  virtual int get_n_log_modules ();
  virtual char *get_prefix (int mod);
  virtual int get_log_action (int mod, int level);
  virtual void set_log_action (int mod, int level, int action);
  virtual char *get_action_name (int action);
  virtual int get_default_log_action (int level) {
	return logfunctions::get_default_action (level);
  }
  virtual void set_default_log_action (int level, int action) {
	logfunctions::set_default_action (level, action);
  }
  virtual const char *get_log_level_name (int level);
  virtual int get_max_log_level ();
  virtual void quit_sim (int code);
  virtual int get_default_rc (char *path, int len);
  virtual int read_rc (char *path);
  virtual int write_rc (char *path, int overwrite);
  virtual int get_log_file (char *path, int len);
  virtual int set_log_file (char *path);
  virtual int get_log_prefix (char *prefix, int len);
  virtual int set_log_prefix (char *prefix);
  virtual int get_floppy_options (int drive, bx_floppy_options *out);
  virtual int get_cdrom_options (int drive, bx_atadevice_options *out, int *device = NULL);
  virtual char *get_floppy_type_name (int type);
  virtual void set_notify_callback (sim_interface_callback_t func, void *arg);
  virtual void get_notify_callback (sim_interface_callback_t *func, void **arg);
  virtual BxEvent* sim_to_ci_event (BxEvent *event);
  virtual int log_msg (const char *prefix, int level, const char *msg);
  virtual int ask_param (bx_id which);
  // ask the user for a pathname
  virtual int ask_filename (char *filename, int maxlen, char *prompt, char *the_default, int flags);
  // called at a regular interval, currently by the keyboard handler.
  virtual void periodic ();
  virtual int create_disk_image (const char *filename, int sectors, Boolean overwrite);
  virtual void refresh_ci ();
  virtual void refresh_vga () {
    // maybe need to check if something has been initialized yet?
    bx_vga.timer_handler (&bx_vga); 
  }
  virtual void handle_events () {
    // maybe need to check if something has been initialized yet?
    bx_gui.handle_events ();
  }
  bx_param_c *get_first_cdrom ();
#if BX_DEBUGGER
  virtual void debug_break ();
  virtual void debug_interpret_cmd (char *cmd);
  virtual char *debug_get_next_command ();
  virtual void debug_puts (const char *cmd);
#endif
};

bx_param_c *
bx_real_sim_c::get_param (bx_id id)
{
  BX_ASSERT (id >= BXP_NULL && id < BXP_THIS_IS_THE_LAST);
  int index = (int)id - BXP_NULL;
  bx_param_c *retval = param_registry[index];
  if (!retval) 
    BX_INFO (("get_param can't find id %u", id));
  return retval;
}

bx_param_num_c *
bx_real_sim_c::get_param_num (bx_id id) {
  bx_param_c *generic = get_param(id);
  if (generic==NULL) {
    BX_PANIC (("get_param_num(%u) could not find a parameter", id));
    return NULL;
  }
  int type = generic->get_type ();
  if (type == BXT_PARAM_NUM || type == BXT_PARAM_BOOL || type == BXT_PARAM_ENUM)
    return (bx_param_num_c *)generic;
  BX_PANIC (("get_param_num %u could not find an integer parameter with that id", id));
  return NULL;
}

bx_param_string_c *
bx_real_sim_c::get_param_string (bx_id id) {
  bx_param_c *generic = get_param(id);
  if (generic==NULL) {
    BX_PANIC (("get_param_string(%u) could not find a parameter", id));
    return NULL;
  }
  if (generic->get_type () == BXT_PARAM_STRING)
    return (bx_param_string_c *)generic;
  BX_PANIC (("get_param_string %u could not find an integer parameter with that id", id));
  return NULL;
}

bx_param_bool_c *
bx_real_sim_c::get_param_bool (bx_id id) {
  bx_param_c *generic = get_param(id);
  if (generic==NULL) {
    BX_PANIC (("get_param_bool(%u) could not find a parameter", id));
    return NULL;
  }
  if (generic->get_type () == BXT_PARAM_BOOL)
    return (bx_param_bool_c *)generic;
  BX_PANIC (("get_param_bool %u could not find a bool parameter with that id", id));
  return NULL;
}

bx_param_enum_c *
bx_real_sim_c::get_param_enum (bx_id id) {
  bx_param_c *generic = get_param(id);
  if (generic==NULL) {
    BX_PANIC (("get_param_enum(%u) could not find a parameter", id));
    return NULL;
  }
  if (generic->get_type () == BXT_PARAM_ENUM)
    return (bx_param_enum_c *)generic;
  BX_PANIC (("get_param_enum %u could not find a enum parameter with that id", id));
  return NULL;
}

void bx_init_siminterface ()
{
  siminterface_log = new logfunctions ();
  siminterface_log->put ("CTRL");
  siminterface_log->settype(CTRLLOG);
  if (SIM == NULL) 
    SIM = new bx_real_sim_c();
}

bx_simulator_interface_c::bx_simulator_interface_c ()
{
}

bx_real_sim_c::bx_real_sim_c ()
{
  callback = NULL;
  callback_ptr = NULL;
  
  enabled = 1;
  int i;
  init_done = 0;
  registry_alloc_size = BXP_THIS_IS_THE_LAST - BXP_NULL;
  param_registry = new bx_param_c*  [registry_alloc_size];
  for (i=0; i<registry_alloc_size; i++)
    param_registry[i] = NULL;
  quit_context = NULL;
}

// called by constructor of bx_param_c, so that every parameter that is
// initialized gets registered.  This builds a list of all parameters
// which can be used to look them up by number (get_param).
bx_real_sim_c::~bx_real_sim_c ()
{
    if ( param_registry != NULL )
    {
        delete [] param_registry;
        param_registry = NULL;
    }
}

int
bx_real_sim_c::register_param (bx_id id, bx_param_c *it)
{
  if (id == BXP_NULL) return 0;
  BX_ASSERT (id >= BXP_NULL && id < BXP_THIS_IS_THE_LAST);
  int index = (int)id - BXP_NULL;
  if (this->param_registry[index] != NULL) {
    BX_INFO (("register_param is overwriting parameter id %d", id));
  }
  this->param_registry[index] = it;
  return 0;
}

void 
bx_real_sim_c::reset_all_param ()
{
  bx_reset_options ();
}

int 
bx_real_sim_c::get_n_log_modules ()
{
  return io->get_n_logfns ();
}

char *
bx_real_sim_c::get_prefix (int mod)
{
  logfunc_t *logfn = io->get_logfn (mod);
  return logfn->getprefix ();
}

int 
bx_real_sim_c::get_log_action (int mod, int level)
{
  logfunc_t *logfn = io->get_logfn (mod);
  return logfn->getonoff (level);
}

void 
bx_real_sim_c::set_log_action (int mod, int level, int action)
{
  // normal
  if (mod >= 0) {
	logfunc_t *logfn = io->get_logfn (mod);
	logfn->setonoff (level, action);
	return;
  }
  // if called with mod<0 loop over all
  int nmod = get_n_log_modules ();
  for (mod=0; mod<nmod; mod++)
	set_log_action (mod, level, action);
}

char *
bx_real_sim_c::get_action_name (int action)
{
  return io->getaction (action);
}

const char *
bx_real_sim_c::get_log_level_name (int level)
{
  return io->getlevel (level);
}

int 
bx_real_sim_c::get_max_log_level ()
{
  return N_LOGLEV;
}

void 
bx_real_sim_c::quit_sim (int code) {
  BX_INFO (("quit_sim called"));
  // use longjmp to quit cleanly, no matter where in the stack we are.
  //fprintf (stderr, "using longjmp() to jump directly to the quit context!\n");
  if (quit_context != NULL) {
    longjmp (*quit_context, 1);
    BX_PANIC (("in bx_real_sim_c::quit_sim, longjmp should never return"));
  }
#if BX_WITH_WX
  // in wxWindows, the whole simulator is running in a separate thread.
  // our only job is to end the thread as soon as possible, NOT to shut
  // down the whole application with an exit.
  BX_CPU(0)->async_event = 1;
  BX_CPU(0)->kill_bochs_request = 1;
  // the cpu loop will exit very soon after this condition is set.
#else
  // just a single thread.  Use exit() to stop the application.
  if (!code)
    BX_PANIC (("Quit simulation command"));
  ::exit (0);
#endif
}

int
bx_real_sim_c::get_default_rc (char *path, int len)
{
  char *rc = bx_find_bochsrc ();
  if (rc == NULL) return -1;
  strncpy (path, rc, len);
  return 0;
}

int 
bx_real_sim_c::read_rc (char *rc)
{
  return bx_read_configuration (rc);
}

// return values:
//   0: written ok
//  -1: failed
//  -2: already exists, and overwrite was off
int 
bx_real_sim_c::write_rc (char *rc, int overwrite)
{
  return bx_write_configuration (rc, overwrite);
}

int 
bx_real_sim_c::get_log_file (char *path, int len)
{
  strncpy (path, bx_options.log.Ofilename->getptr (), len);
  return 0;
}

int 
bx_real_sim_c::set_log_file (char *path)
{
  bx_options.log.Ofilename->set (path);
  return 0;
}

int 
bx_real_sim_c::get_log_prefix (char *prefix, int len)
{
  strncpy (prefix, bx_options.log.Oprefix->getptr (), len);
  return 0;
}

int 
bx_real_sim_c::set_log_prefix (char *prefix)
{
  bx_options.log.Oprefix->set (prefix);
  return 0;
}

int 
bx_real_sim_c::get_floppy_options (int drive, bx_floppy_options *out)
{
  *out = (drive==0)? bx_options.floppya : bx_options.floppyb;
  return 0;
}

int 
bx_real_sim_c::get_cdrom_options (int level, bx_atadevice_options *out, int *where)
{
  for (Bit8u channel=0; channel<BX_MAX_ATA_CHANNEL; channel++) {
    for (Bit8u device=0; device<2; device++) {
      if (bx_options.atadevice[channel][device].Otype->get() == BX_ATA_DEVICE_CDROM) {
        if (level==0) {
          *out = bx_options.atadevice[channel][device];
	  if (where != NULL) *where=(channel*2)+device;
          return 1;
          }
        else level--;
	}
      }
    }
  return 0;
}

char *floppy_type_names[] = { "none", "1.2M", "1.44M", "2.88M", "720K", "360K", NULL };
int floppy_type_n_sectors[] = { -1, 80*2*15, 80*2*18, 80*2*36, 80*2*9, 40*2*9 };
int n_floppy_type_names = 6;
char *floppy_status_names[] = { "ejected", "inserted", NULL };
int n_floppy_status_names = 2;
char *floppy_bootdisk_names[] = { "floppy", "hard","cdrom", NULL };
int n_floppy_bootdisk_names = 3;
char *loader_os_names[] = { "none", "linux", "nullkernel", NULL };
int n_loader_os_names = 3;
char *keyboard_type_names[] = { "xt", "at", "mf", NULL };
int n_keyboard_type_names = 3;
char *atadevice_type_names[] = { "hard disk", "cdrom", NULL };
int n_atadevice_type_names = 2;
char *atadevice_status_names[] = { "ejected", "inserted", NULL };
int n_atadevice_status_names = 2;
char *atadevice_biosdetect_names[] = { "none", "auto", "cmos", NULL };
int n_atadevice_biosdetect_names = 3;
char *atadevice_translation_names[] = { "none", "lba", "large", NULL };
int n_atadevice_translation_names = 3;

char *
bx_real_sim_c::get_floppy_type_name (int type)
{
  BX_ASSERT (type >= BX_FLOPPY_NONE && type <= BX_FLOPPY_LAST);
  type -= BX_FLOPPY_NONE;
  return floppy_type_names[type];
}

void 
bx_real_sim_c::set_notify_callback (sim_interface_callback_t func, void *arg)
{
  callback = func;
  callback_ptr = arg;
}

void bx_real_sim_c::get_notify_callback (
    sim_interface_callback_t *func,
    void **arg)
{
  *func = callback;
  *arg = callback_ptr;
}

BxEvent *
bx_real_sim_c::sim_to_ci_event (BxEvent *event)
{
  if (callback == NULL) {
    BX_ERROR (("notify called, but no callback function is registered"));
    return NULL;
  } else {
    return (*callback)(callback_ptr, event);
  }
}

// returns 0 for continue, 1 for alwayscontinue, 2 for die.
int 
bx_real_sim_c::log_msg (const char *prefix, int level, const char *msg)
{
  BxEvent be;
  be.type = BX_SYNC_EVT_LOG_ASK;
  be.u.logmsg.prefix = prefix;
  be.u.logmsg.level = level;
  be.u.logmsg.msg = msg;
  //fprintf (stderr, "calling notify.\n");
  sim_to_ci_event (&be);
  return be.retcode;
}

// Called by simulator whenever it needs the user to choose a new value
// for a registered parameter.  Create a synchronous ASK_PARAM event, 
// send it to the CI, and wait for the response.  The CI will call the
// set() method on the parameter if the user changes the value.
int 
bx_real_sim_c::ask_param (bx_id param)
{
  bx_param_c *paramptr = SIM->get_param(param);
  BX_ASSERT (paramptr != NULL);
  // create appropriate event
  BxEvent event;
  event.type = BX_SYNC_EVT_ASK_PARAM;
  event.u.param.param = paramptr;
  sim_to_ci_event (&event);
  return event.retcode;
}

int
bx_real_sim_c::ask_filename (char *filename, int maxlen, char *prompt, char *the_default, int flags)
{
  // implement using ASK_PARAM on a newly created param.  I can't use
  // ask_param because I don't intend to register this param.
  BxEvent event;
  bx_param_string_c param (BXP_NULL, "filename", prompt, the_default, maxlen);
  flags |= param.BX_IS_FILENAME;
  param.get_options()->set (flags);
  event.type = BX_SYNC_EVT_ASK_PARAM;
  event.u.param.param = &param;
  sim_to_ci_event (&event);
  if (event.retcode >= 0)
    memcpy (filename, param.getptr(), maxlen);
  return event.retcode;
}

void
bx_real_sim_c::periodic ()
{
  // give the GUI a chance to do periodic things on the bochs thread. in 
  // particular, notice if the thread has been asked to die.
  BxEvent tick;
  tick.type = BX_SYNC_EVT_TICK;
  sim_to_ci_event (&tick);
  if (tick.retcode < 0) {
    BX_INFO (("Bochs thread has been asked to quit."));
    bx_atexit ();
    quit_sim (0);
  }
  static int refresh_counter = 0;
  if (++refresh_counter == 50) {
    // only ask the CI to refresh every 50 times periodic() is called.
    // This should obviously be configurable because system speeds and
    // user preferences vary.
    refresh_ci ();
    refresh_counter = 0;
  }
#if 0
  // watch for memory leaks.  Allocate a small block of memory, print the
  // pointer that is returned, then free.
  BxEvent *memcheck = new BxEvent ();
  BX_INFO(("memory allocation at %p", memcheck));
  delete memcheck;
#endif
}

// create a disk image file called filename, size=512 bytes * sectors.
// If overwrite is true and the file exists, returns -1 without changing it.
// Otherwise, opens up the image and starts writing.  Returns -2 if
// the image could not be opened, or -3 if there are failures during
// write, e.g. disk full.
// 
// wxWindows: This may be called from the gui thread.
int 
bx_real_sim_c::create_disk_image (
    const char *filename,
    int sectors,
    Boolean overwrite) 
{
  FILE *fp;
  if (!overwrite) {
    // check for existence first
    fp = fopen (filename, "r");
    if (fp) {
      // yes it exists
      fclose (fp);
      return -1;
    }
  }
  fp = fopen (filename, "w");
  if (fp == NULL) {
#ifdef HAVE_PERROR
    char buffer[1024];
    sprintf (buffer, "while opening '%s' for writing", filename);
    perror (buffer);
    // not sure how to get this back into the CI
#endif
    return -2;
  }
  int sec = sectors;
  /*
   * seek to sec*512-1 and write a single character.
   * can't just do: fseek(fp, 512*sec-1, SEEK_SET)
   * because 512*sec may be too large for signed int.
   */
  while (sec > 0)
  {
    /* temp <-- min(sec, 4194303)
     * 4194303 is (int)(0x7FFFFFFF/512)
     */
    int temp = ((sec < 4194303) ? sec : 4194303);
    fseek(fp, 512*temp, SEEK_CUR);
    sec -= temp;
  }

  fseek(fp, -1, SEEK_CUR);
  if (fputc('\0', fp) == EOF)
  {
    fclose (fp);
    return -3;
  }
  fclose (fp);
  return 0;
}

void bx_real_sim_c::refresh_ci () {
#if BX_WITH_WX
  // presently, only wxWindows interface uses these events
  // It's an async event, so allocate a pointer and send it.
  // The event will be freed by the recipient.
  BxEvent *event = new BxEvent ();
  event->type = BX_ASYNC_EVT_REFRESH;
  sim_to_ci_event (event);
#endif
}

bx_param_c *
bx_real_sim_c::get_first_cdrom ()
{
  for (int channel=0; channel<BX_MAX_ATA_CHANNEL; channel++) {
    if (!bx_options.ata[channel].Opresent->get ())
      continue;
    for (int slave=0; slave<2; slave++) {
      Bit32u present = bx_options.atadevice[channel][slave].Opresent->get ();
      Bit32u type = bx_options.atadevice[channel][slave].Otype->get ();
      if (present && type == BX_ATA_DEVICE_CDROM) {
	return bx_options.atadevice[channel][slave].Omenu;
      }
    }
  }
  return NULL;
}

#if BX_DEBUGGER

// this can be safely called from either thread.
void bx_real_sim_c::debug_break () {
  bx_debug_break ();
}

// this should only be called from the sim_thread.
void bx_real_sim_c::debug_interpret_cmd (char *cmd) {
#if BX_WITH_WX
  if (!isSimThread ()) {
    fprintf (stderr, "ERROR: debug_interpret_cmd called but not from sim_thread\n");
    return;
  }
#endif
  bx_dbg_interpret_line (cmd);
}

char *bx_real_sim_c::debug_get_next_command ()
{
  fprintf (stderr, "begin debug_get_next_command\n");
  BxEvent event;
  event.type = BX_SYNC_EVT_GET_DBG_COMMAND;
  BX_INFO (("asking for next debug command"));
  sim_to_ci_event (&event);
  BX_INFO (("received next debug command: '%s'", event.u.debugcmd.command));
  if (event.retcode >= 0)
    return event.u.debugcmd.command;
  return NULL;
}

void bx_real_sim_c::debug_puts (const char *text)
{
#if BX_WITH_WX
  // send message to the wxWindows debugger
  BxEvent *event = new BxEvent ();
  event->type = BX_ASYNC_EVT_DBG_MSG;
  event->u.logmsg.msg = text;
  sim_to_ci_event (event);
  // the event will be freed by the recipient
#else
  // text mode debugger: just write to console
  fputs (text, stderr);
  delete text;
#endif
}
#endif

/////////////////////////////////////////////////////////////////////////
// define methods of bx_param_* and family
/////////////////////////////////////////////////////////////////////////

bx_object_c::bx_object_c (bx_id id)
{
  this->id = id;
  this->type = BXT_OBJECT;
}

void
bx_object_c::set_type (bx_objtype type)
{
  this->type = type;
}

const char* bx_param_c::default_text_format = NULL;

bx_param_c::bx_param_c (bx_id id, char *name, char *description)
  : bx_object_c (id)
{
  set_type (BXT_PARAM);
  this->name = name;
  this->description = description;
  this->text_format = default_text_format;
  this->ask_format = NULL;
  this->runtime_param = 0;
  this->enabled = 1;
  SIM->register_param (id, this);
}

const char* bx_param_c::set_default_format (const char *f) {
  const char *old = default_text_format;
  default_text_format = f; 
  return old;
}

bx_param_num_c::bx_param_num_c (bx_id id,
    char *name,
    char *description,
    Bit32s min, Bit32s max, Bit32s initial_val)
  : bx_param_c (id, name, description)
{
  set_type (BXT_PARAM_NUM);
  this->min = min;
  this->max = max;
  this->initial_val = initial_val;
  this->val.number = initial_val;
  this->handler = NULL;
  this->base = default_base;
  // dependent_list must be initialized before the set(),
  // because set calls update_dependents().
  dependent_list = NULL;
  set (initial_val);
}

Bit32u bx_param_num_c::default_base = 10;

Bit32u bx_param_num_c::set_default_base (Bit32u val) {
  Bit32u old = default_base;
  default_base = val; 
  return old;
}

void 
bx_param_num_c::reset ()
{
  this->val.number = initial_val;
}

void 
bx_param_num_c::set_handler (param_event_handler handler)
{ 
  this->handler = handler; 
  // now that there's a handler, call set once to run the handler immediately
  //set (get ());
}

Bit32s 
bx_param_num_c::get ()
{
  if (handler) {
    // the handler can decide what value to return and/or do some side effect
    return (*handler)(this, 0, val.number);
  } else {
    // just return the value
    return val.number;
  }
}

void
bx_param_num_c::set (Bit32s newval)
{
  if (handler) {
    // the handler can override the new value and/or perform some side effect
    val.number = newval;
    (*handler)(this, 1, newval);
  } else {
    // just set the value.  This code does not check max/min.
    val.number = newval;
  }
  if (val.number < min || val.number > max) 
    BX_PANIC (("numerical parameter %s was set to %d, which is out of range %d to %d", get_name (), val.number, min, max));
  if (dependent_list != NULL) update_dependents ();
}

void bx_param_num_c::update_dependents ()
{
  if (dependent_list) {
    int en = val.number && enabled;
    for (int i=0; i<dependent_list->get_size (); i++) {
      bx_param_c *param = dependent_list->get (i);
      if (param != this)
	param->set_enabled (en);
    }
  }
}

void
bx_param_num_c::set_enabled (int en)
{
  bx_param_c::set_enabled (en);
  update_dependents ();
}

bx_shadow_num_c::bx_shadow_num_c (bx_id id,
    char *name,
    char *description,
    Bit32s min,
    Bit32s max,
    Bit32s *ptr_to_real_val,
    Bit8u highbit,
    Bit8u lowbit)
: bx_param_num_c (id, name, description, min, max, *ptr_to_real_val)
{
  this->varsize = 16;
  this->lowbit = lowbit;
  this->mask = (1 << (highbit - lowbit)) - 1;
  val.p32bit = ptr_to_real_val;
}

bx_shadow_num_c::bx_shadow_num_c (bx_id id,
    char *name,
    char *description,
    Bit32s min, Bit32s max, Bit32u *ptr_to_real_val,
    Bit8u highbit,
    Bit8u lowbit)
: bx_param_num_c (id, name, description, min, max, *ptr_to_real_val)
{
  this->varsize = 32;
  this->lowbit = lowbit;
  this->mask = (1 << (highbit - lowbit)) - 1;
  val.p32bit = (Bit32s*) ptr_to_real_val;
}

bx_shadow_num_c::bx_shadow_num_c (bx_id id,
    char *name,
    Bit32u *ptr_to_real_val,
    Bit8u highbit,
    Bit8u lowbit)
: bx_param_num_c (id, name, "", BX_MIN_INT, BX_MAX_INT, *ptr_to_real_val)
{
  this->varsize = 32;
  this->lowbit = lowbit;
  this->mask = (1 << (highbit - lowbit)) - 1;
  val.p32bit = (Bit32s*) ptr_to_real_val;
}

bx_shadow_num_c::bx_shadow_num_c (bx_id id,
    char *name,
    Bit16u *ptr_to_real_val,
    Bit8u highbit,
    Bit8u lowbit)
: bx_param_num_c (id, name, "", BX_MIN_INT, BX_MAX_INT, *ptr_to_real_val)
{
  this->varsize = 16;
  this->lowbit = lowbit;
  this->mask = (1 << (highbit - lowbit)) - 1;
  val.p16bit = (Bit16s*) ptr_to_real_val;
}

bx_shadow_num_c::bx_shadow_num_c (bx_id id,
    char *name,
    Bit16s *ptr_to_real_val,
    Bit8u highbit,
    Bit8u lowbit)
: bx_param_num_c (id, name, "", BX_MIN_INT, BX_MAX_INT, *ptr_to_real_val)
{
  this->varsize = 16;
  this->lowbit = lowbit;
  this->mask = (1 << (highbit - lowbit)) - 1;
  val.p16bit = ptr_to_real_val;
}

Bit32s
bx_shadow_num_c::get () {
  Bit32u current;
  switch (varsize) {
    case 8: current = *(val.p8bit);  break;
    case 16: current = *(val.p16bit);  break;
    case 32: current = *(val.p32bit);  break;
  }
  current = (current >> lowbit) & mask;
  if (handler) {
    // the handler can decide what value to return and/or do some side effect
    return (*handler)(this, 0, current) & mask;
  } else {
    // just return the value
    return current;
  }
}

void
bx_shadow_num_c::set (Bit32s newval)
{
  Bit32u tmp;
  if (newval < min || newval > max)
    BX_PANIC (("numerical parameter %s was set to %d, which is out of range %d to %d", get_name (), newval, min, max));
  switch (varsize) {
    case 8: 
      tmp = (*(val.p8bit) >> lowbit) & mask;
      tmp |= (newval & mask) << lowbit;
      *(val.p8bit) = tmp;
      break;
    case 16:
      tmp = (*(val.p16bit) >> lowbit) & mask;
      tmp |= (newval & mask) << lowbit;
      *(val.p16bit) = tmp;
      break;
    case 32:
      tmp = (*(val.p32bit) >> lowbit) & mask;
      tmp |= (newval & mask) << lowbit;
      *(val.p32bit) = tmp;
      break;
  }
  if (handler) {
    // the handler can override the new value and/or perform some side effect
    (*handler)(this, 1, tmp);
  }
}

bx_param_bool_c::bx_param_bool_c (bx_id id,
    char *name,
    char *description,
    Bit32s initial_val)
  : bx_param_num_c (id, name, description, 0, 1, initial_val)
{
  set_type (BXT_PARAM_BOOL);
  set (initial_val);
}

bx_shadow_bool_c::bx_shadow_bool_c (bx_id id,
      char *name,
      Boolean *ptr_to_real_val,
      Bit8u bitnum)
  : bx_param_bool_c (id, name, "", (Bit32s) *ptr_to_real_val)
{
  val.pbool = ptr_to_real_val;
  this->bitnum = bitnum;
}

Bit32s
bx_shadow_bool_c::get () {
  if (handler) {
    // the handler can decide what value to return and/or do some side effect
    Bit32s ret = (*handler)(this, 0, (Bit32s) *(val.pbool));
    return (ret>>bitnum) & 1;
  } else {
    // just return the value
    return (*(val.pbool)) & 1;
  }
}

void
bx_shadow_bool_c::set (Bit32s newval)
{
  // only change the bitnum bit
  Bit32s tmp = (newval&1) << bitnum;
  *(val.pbool) &= ~tmp;
  *(val.pbool) |= tmp;
  if (handler) {
    // the handler can override the new value and/or perform some side effect
    (*handler)(this, 1, newval&1);
  }
}

bx_param_enum_c::bx_param_enum_c (bx_id id, 
      char *name,
      char *description,
      char **choices,
      Bit32s initial_val,
      Bit32s value_base)
  : bx_param_num_c (id, name, description, value_base, BX_MAX_INT, initial_val)
{
  set_type (BXT_PARAM_ENUM);
  this->choices = choices;
  // count number of choices, set max
  char **p = choices;
  while (*p != NULL) p++;
  this->min = value_base;
  // now that the max is known, replace the BX_MAX_INT sent to the parent
  // class constructor with the real max.
  this->max = value_base + (p - choices - 1);
  set (initial_val);
}

bx_param_string_c::bx_param_string_c (bx_id id,
    char *name,
    char *description,
    char *initial_val,
    int maxsize)
  : bx_param_c (id, name, description)
{
  set_type (BXT_PARAM_STRING);
  if (maxsize < 0) 
    maxsize = strlen(initial_val) + 1;
  this->val = new char[maxsize];
  this->initial_val = new char[maxsize];
  this->handler = NULL;
  this->maxsize = maxsize;
  strncpy (this->val, initial_val, maxsize);
  strncpy (this->initial_val, initial_val, maxsize);
  this->options = new bx_param_num_c (BXP_NULL,
      "stringoptions", NULL, 0, BX_MAX_INT, 0);
  set (initial_val);
}

bx_param_filename_c::bx_param_filename_c (bx_id id,
    char *name,
    char *description,
    char *initial_val,
    int maxsize)
  : bx_param_string_c (id, name, description, initial_val, maxsize)
{
  get_options()->set (BX_IS_FILENAME);
}

bx_param_string_c::~bx_param_string_c ()
{
    if ( this->val != NULL )
    {
        delete [] this->val;
        this->val = NULL;
    }
    if ( this->initial_val != NULL )
    {
        delete [] this->initial_val;
        this->initial_val = NULL;
    }

    if ( this->options != NULL )
    {
        delete [] this->options;
        this->options = NULL;
    }
}

void 
bx_param_string_c::reset () {
  strncpy (this->val, this->initial_val, maxsize);
}

void 
bx_param_string_c::set_handler (param_string_event_handler handler)
{
  this->handler = handler; 
  // now that there's a handler, call set once to run the handler immediately
  //set (getptr ());
}

Bit32s
bx_param_string_c::get (char *buf, int len)
{
  if (options->get () & BX_RAW_BYTES)
    memcpy (buf, val, len);
  else
    strncpy (buf, val, len);
  if (handler) {
    // the handler can choose to replace the value in val/len.  Also its
    // return value is passed back as the return value of get.
    (*handler)(this, 0, buf, len);
  }
  return 0;
}

void 
bx_param_string_c::set (char *buf)
{
  if (options->get () & BX_RAW_BYTES)
    memcpy (val, buf, maxsize);
  else
    strncpy (val, buf, maxsize);
  if (handler) {
    // the handler can return a different char* to be copied into the value
    buf = (*handler)(this, 1, buf, -1);
  }
}

bx_list_c::bx_list_c (bx_id id, int maxsize)
  : bx_param_c (id, "list", "")
{
  set_type (BXT_LIST);
  this->size = 0;
  this->maxsize = maxsize;
  this->list = new bx_param_c*  [maxsize];
  init ();
}

bx_list_c::bx_list_c (bx_id id, char *name, char *description, int maxsize)
  : bx_param_c (id, name, description)
{
  set_type (BXT_LIST);
  this->size = 0;
  this->maxsize = maxsize;
  this->list = new bx_param_c*  [maxsize];
  init ();
}

bx_list_c::bx_list_c (bx_id id, char *name, char *description, bx_param_c **init_list)
  : bx_param_c (id, name, description)
{
  set_type (BXT_LIST);
  this->size = 0;
  while (init_list[this->size] != NULL)
    this->size++;
  this->maxsize = this->size;
  this->list = new bx_param_c*  [maxsize];
  for (int i=0; i<this->size; i++)
    this->list[i] = init_list[i];
  init ();
}

bx_list_c::~bx_list_c()
{
    if (this->list)
    {
        delete [] this->list;
        this->list = NULL;
    }
    if ( this->title != NULL)
    {
        delete this->title;
        this->title = NULL;
    }
    if (this->options != NULL)
    {
        delete this->options;
        this->options = NULL;
    }
    if ( this->choice != NULL )
    {
        delete this->choice;
        this->choice = NULL;
    }
}

void
bx_list_c::init ()
{
  // the title defaults to the name
  this->title = new bx_param_string_c (BXP_NULL,
      "title of list",
      "",
      get_name (), 80);
  this->options = new bx_param_num_c (BXP_NULL,
      "list_option", "", 0, BX_MAX_INT,
      0);
  this->choice = new bx_param_num_c (BXP_NULL,
      "list_choice", "", 0, BX_MAX_INT,
      1);
  this->parent = NULL;
}

bx_list_c *
bx_list_c::clone ()
{
  bx_list_c *newlist = new bx_list_c (BXP_NULL, name, description, maxsize);
  for (int i=0; i<get_size (); i++)
    newlist->add (get(i));
  newlist->set_options (get_options ());
  newlist->set_parent (get_parent ());
  return newlist;
}

void
bx_list_c::add (bx_param_c *param)
{
  if (this->size >= this->maxsize)
    BX_PANIC (("add param %u to bx_list_c id=%u: list capacity exceeded", param->get_id (), get_id ()));
  list[size] = param;
  size++;
}

bx_param_c *
bx_list_c::get (int index)
{
  BX_ASSERT (index >= 0 && index < size);
  return list[index];
}