settings.cpp

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/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include "stdafx.h"
#include <charconv>
#include "settings_table.h"
#include "debug.h"
#include "currency.h"
#include "network/network.h"
#include "network/network_func.h"
#include "network/core/config.h"
#include "command_func.h"
#include "console_func.h"
#include "genworld.h"
#include "window_func.h"
#include "company_func.h"
#include "rev.h"
#include "error.h"
#include "gamelog.h"
#include "settings_func.h"
#include "ini_type.h"
#include "ai/ai_config.hpp"
#include "game/game_config.hpp"
#include "newgrf_config.h"
#include "fios.h"
#include "fileio_func.h"
 
#include "table/strings.h"
 
#include "safeguards.h"
 
ClientSettings _settings_client;
GameSettings _settings_game;     
GameSettings _settings_newgame;  
VehicleDefaultSettings _old_vds; 
std::string _config_file; 
std::string _private_file; 
std::string _secrets_file; 
 
typedef std::list<ErrorMessageData> ErrorList;
static ErrorList _settings_error_list; 
 
static auto &GenericSettingTables()
{
  static const SettingTable _generic_setting_tables[] = {
    _difficulty_settings,
    _economy_settings,
    _game_settings,
    _gui_settings,
    _linkgraph_settings,
    _locale_settings,
    _multimedia_settings,
    _network_settings,
    _news_display_settings,
    _pathfinding_settings,
    _script_settings,
    _world_settings,
  };
  return _generic_setting_tables;
}
 
static auto &PrivateSettingTables()
{
  static const SettingTable _private_setting_tables[] = {
    _network_private_settings,
  };
  return _private_setting_tables;
}
 
static auto &SecretSettingTables()
{
  static const SettingTable _secrets_setting_tables[] = {
    _network_secrets_settings,
  };
  return _secrets_setting_tables;
}
 
typedef void SettingDescProc(IniFile &ini, const SettingTable &desc, const char *grpname, void *object, bool only_startup);
typedef void SettingDescProcList(IniFile &ini, const char *grpname, StringList &list);
 
static bool IsSignedVarMemType(VarType vt)
{
  switch (GetVarMemType(vt)) {
    case SLE_VAR_I8:
    case SLE_VAR_I16:
    case SLE_VAR_I32:
    case SLE_VAR_I64:
      return true;
  }
  return false;
}
 
class ConfigIniFile : public IniFile {
private:
  inline static const char * const list_group_names[] = {
    "bans",
    "newgrf",
    "servers",
    "server_bind_addresses",
    nullptr,
  };
 
public:
  ConfigIniFile(const std::string &filename) : IniFile(list_group_names)
  {
    this->LoadFromDisk(filename, NO_DIRECTORY);
  }
};
 
enum IniFileVersion : uint32 {
  IFV_0,               
  IFV_PRIVATE_SECRETS, 
  IFV_GAME_TYPE,       
 
  IFV_MAX_VERSION,     
};
 
const uint16 INIFILE_VERSION = (IniFileVersion)(IFV_MAX_VERSION - 1); 
 
size_t OneOfManySettingDesc::ParseSingleValue(const char *str, size_t len, const std::vector<std::string> &many)
{
  /* check if it's an integer */
  if (isdigit(*str)) return strtoul(str, nullptr, 0);
 
  size_t idx = 0;
  for (auto one : many) {
    if (one.size() == len && strncmp(one.c_str(), str, len) == 0) return idx;
    idx++;
  }
 
  return (size_t)-1;
}
 
static size_t LookupManyOfMany(const std::vector<std::string> &many, const char *str)
{
  const char *s;
  size_t r;
  size_t res = 0;
 
  for (;;) {
    /* skip "whitespace" */
    while (*str == ' ' || *str == '\t' || *str == '|') str++;
    if (*str == 0) break;
 
    s = str;
    while (*s != 0 && *s != ' ' && *s != '\t' && *s != '|') s++;
 
    r = OneOfManySettingDesc::ParseSingleValue(str, s - str, many);
    if (r == (size_t)-1) return r;
 
    SetBit(res, (uint8)r); // value found, set it
    if (*s == 0) break;
    str = s + 1;
  }
  return res;
}
 
template<typename T>
static int ParseIntList(const char *p, T *items, int maxitems)
{
  int n = 0; // number of items read so far
  bool comma = false; // do we accept comma?
 
  while (*p != '\0') {
    switch (*p) {
      case ',':
        /* Do not accept multiple commas between numbers */
        if (!comma) return -1;
        comma = false;
        FALLTHROUGH;
 
      case ' ':
        p++;
        break;
 
      default: {
        if (n == maxitems) return -1; // we don't accept that many numbers
        char *end;
        unsigned long v = strtoul(p, &end, 0);
        if (p == end) return -1; // invalid character (not a number)
        if (sizeof(T) < sizeof(v)) v = Clamp<unsigned long>(v, std::numeric_limits<T>::min(), std::numeric_limits<T>::max());
        items[n++] = v;
        p = end; // first non-number
        comma = true; // we accept comma now
        break;
      }
    }
  }
 
  /* If we have read comma but no number after it, fail.
   * We have read comma when (n != 0) and comma is not allowed */
  if (n != 0 && !comma) return -1;
 
  return n;
}
 
static bool LoadIntList(const char *str, void *array, int nelems, VarType type)
{
  unsigned long items[64];
  int i, nitems;
 
  if (str == nullptr) {
    memset(items, 0, sizeof(items));
    nitems = nelems;
  } else {
    nitems = ParseIntList(str, items, lengthof(items));
    if (nitems != nelems) return false;
  }
 
  switch (type) {
    case SLE_VAR_BL:
    case SLE_VAR_I8:
    case SLE_VAR_U8:
      for (i = 0; i != nitems; i++) ((byte*)array)[i] = items[i];
      break;
 
    case SLE_VAR_I16:
    case SLE_VAR_U16:
      for (i = 0; i != nitems; i++) ((uint16*)array)[i] = items[i];
      break;
 
    case SLE_VAR_I32:
    case SLE_VAR_U32:
      for (i = 0; i != nitems; i++) ((uint32*)array)[i] = items[i];
      break;
 
    default: NOT_REACHED();
  }
 
  return true;
}
 
void ListSettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  const byte *p = static_cast<const byte *>(GetVariableAddress(object, this->save));
  int i, v = 0;
 
  for (i = 0; i != this->save.length; i++) {
    switch (GetVarMemType(this->save.conv)) {
      case SLE_VAR_BL:
      case SLE_VAR_I8:  v = *(const   int8 *)p; p += 1; break;
      case SLE_VAR_U8:  v = *(const  uint8 *)p; p += 1; break;
      case SLE_VAR_I16: v = *(const  int16 *)p; p += 2; break;
      case SLE_VAR_U16: v = *(const uint16 *)p; p += 2; break;
      case SLE_VAR_I32: v = *(const  int32 *)p; p += 4; break;
      case SLE_VAR_U32: v = *(const uint32 *)p; p += 4; break;
      default: NOT_REACHED();
    }
    if (IsSignedVarMemType(this->save.conv)) {
      buf += seprintf(buf, last, (i == 0) ? "%d" : ",%d", v);
    } else {
      buf += seprintf(buf, last, (i == 0) ? "%u" : ",%u", v);
    }
  }
}
 
char *OneOfManySettingDesc::FormatSingleValue(char *buf, const char *last, uint id) const
{
  if (id >= this->many.size()) {
    return buf + seprintf(buf, last, "%d", id);
  }
  return strecpy(buf, this->many[id].c_str(), last);
}
 
void OneOfManySettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  uint id = (uint)this->Read(object);
  this->FormatSingleValue(buf, last, id);
}
 
void ManyOfManySettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  uint bitmask = (uint)this->Read(object);
  bool first = true;
  for (uint id : SetBitIterator(bitmask)) {
    if (!first) buf = strecpy(buf, "|", last);
    buf = this->FormatSingleValue(buf, last, id);
    first = false;
  }
}
 
size_t IntSettingDesc::ParseValue(const char *str) const
{
  char *end;
  size_t val = strtoul(str, &end, 0);
  if (end == str) {
    ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
    msg.SetDParamStr(0, str);
    msg.SetDParamStr(1, this->GetName());
    _settings_error_list.push_back(msg);
    return this->def;
  }
  if (*end != '\0') {
    ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_TRAILING_CHARACTERS);
    msg.SetDParamStr(0, this->GetName());
    _settings_error_list.push_back(msg);
  }
  return val;
}
 
size_t OneOfManySettingDesc::ParseValue(const char *str) const
{
  size_t r = OneOfManySettingDesc::ParseSingleValue(str, strlen(str), this->many);
  /* if the first attempt of conversion from string to the appropriate value fails,
    * look if we have defined a converter from old value to new value. */
  if (r == (size_t)-1 && this->many_cnvt != nullptr) r = this->many_cnvt(str);
  if (r != (size_t)-1) return r; // and here goes converted value
 
  ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
  msg.SetDParamStr(0, str);
  msg.SetDParamStr(1, this->GetName());
  _settings_error_list.push_back(msg);
  return this->def;
}
 
size_t ManyOfManySettingDesc::ParseValue(const char *str) const
{
  size_t r = LookupManyOfMany(this->many, str);
  if (r != (size_t)-1) return r;
  ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
  msg.SetDParamStr(0, str);
  msg.SetDParamStr(1, this->GetName());
  _settings_error_list.push_back(msg);
  return this->def;
}
 
size_t BoolSettingDesc::ParseValue(const char *str) const
{
  if (strcmp(str, "true") == 0 || strcmp(str, "on") == 0 || strcmp(str, "1") == 0) return true;
  if (strcmp(str, "false") == 0 || strcmp(str, "off") == 0 || strcmp(str, "0") == 0) return false;
 
  ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_VALUE);
  msg.SetDParamStr(0, str);
  msg.SetDParamStr(1, this->GetName());
  _settings_error_list.push_back(msg);
  return this->def;
}
 
void IntSettingDesc::MakeValueValidAndWrite(const void *object, int32 val) const
{
  this->MakeValueValid(val);
  this->Write(object, val);
}
 
void IntSettingDesc::MakeValueValid(int32 &val) const
{
  /* We need to take special care of the uint32 type as we receive from the function
   * a signed integer. While here also bail out on 64-bit settings as those are not
   * supported. Unsigned 8 and 16-bit variables are safe since they fit into a signed
   * 32-bit variable
   * TODO: Support 64-bit settings/variables; requires 64 bit over command protocol! */
  switch (GetVarMemType(this->save.conv)) {
    case SLE_VAR_NULL: return;
    case SLE_VAR_BL:
    case SLE_VAR_I8:
    case SLE_VAR_U8:
    case SLE_VAR_I16:
    case SLE_VAR_U16:
    case SLE_VAR_I32: {
      /* Override the minimum value. No value below this->min, except special value 0 */
      if (!(this->flags & SF_GUI_0_IS_SPECIAL) || val != 0) {
        if (!(this->flags & SF_GUI_DROPDOWN)) {
          /* Clamp value-type setting to its valid range */
          val = Clamp(val, this->min, this->max);
        } else if (val < this->min || val > (int32)this->max) {
          /* Reset invalid discrete setting (where different values change gameplay) to its default value */
          val = this->def;
        }
      }
      break;
    }
    case SLE_VAR_U32: {
      /* Override the minimum value. No value below this->min, except special value 0 */
      uint32 uval = (uint32)val;
      if (!(this->flags & SF_GUI_0_IS_SPECIAL) || uval != 0) {
        if (!(this->flags & SF_GUI_DROPDOWN)) {
          /* Clamp value-type setting to its valid range */
          uval = ClampU(uval, this->min, this->max);
        } else if (uval < (uint)this->min || uval > this->max) {
          /* Reset invalid discrete setting to its default value */
          uval = (uint32)this->def;
        }
      }
      val = (int32)uval;
      return;
    }
    case SLE_VAR_I64:
    case SLE_VAR_U64:
    default: NOT_REACHED();
  }
}
 
void IntSettingDesc::Write(const void *object, int32 val) const
{
  void *ptr = GetVariableAddress(object, this->save);
  WriteValue(ptr, this->save.conv, (int64)val);
}
 
int32 IntSettingDesc::Read(const void *object) const
{
  void *ptr = GetVariableAddress(object, this->save);
  return (int32)ReadValue(ptr, this->save.conv);
}
 
void StringSettingDesc::MakeValueValid(std::string &str) const
{
  if (this->max_length == 0 || str.size() < this->max_length) return;
 
  /* In case a maximum length is imposed by the setting, the length
   * includes the '\0' termination for network transfer purposes.
   * Also ensure the string is valid after chopping of some bytes. */
  std::string stdstr(str, this->max_length - 1);
  str.assign(StrMakeValid(stdstr, SVS_NONE));
}
 
void StringSettingDesc::Write(const void *object, const std::string &str) const
{
  reinterpret_cast<std::string *>(GetVariableAddress(object, this->save))->assign(str);
}
 
const std::string &StringSettingDesc::Read(const void *object) const
{
  return *reinterpret_cast<std::string *>(GetVariableAddress(object, this->save));
}
 
static void IniLoadSettings(IniFile &ini, const SettingTable &settings_table, const char *grpname, void *object, bool only_startup)
{
  IniGroup *group;
  IniGroup *group_def = ini.GetGroup(grpname);
 
  for (auto &desc : settings_table) {
    const SettingDesc *sd = GetSettingDesc(desc);
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    if (sd->startup != only_startup) continue;
 
    /* For settings.xx.yy load the settings from [xx] yy = ? */
    std::string s{ sd->GetName() };
    auto sc = s.find('.');
    if (sc != std::string::npos) {
      group = ini.GetGroup(s.substr(0, sc));
      s = s.substr(sc + 1);
    } else {
      group = group_def;
    }
 
    IniItem *item = group->GetItem(s, false);
    if (item == nullptr && group != group_def) {
      /* For settings.xx.yy load the settings from [settings] yy = ? in case the previous
       * did not exist (e.g. loading old config files with a [settings] section */
      item = group_def->GetItem(s, false);
    }
    if (item == nullptr) {
      /* For settings.xx.zz.yy load the settings from [zz] yy = ? in case the previous
       * did not exist (e.g. loading old config files with a [yapf] section */
      sc = s.find('.');
      if (sc != std::string::npos) item = ini.GetGroup(s.substr(0, sc))->GetItem(s.substr(sc + 1), false);
    }
 
    sd->ParseValue(item, object);
  }
}
 
void IntSettingDesc::ParseValue(const IniItem *item, void *object) const
{
  size_t val = (item == nullptr) ? this->def : this->ParseValue(item->value.has_value() ? item->value->c_str() : "");
  this->MakeValueValidAndWrite(object, (int32)val);
}
 
void StringSettingDesc::ParseValue(const IniItem *item, void *object) const
{
  std::string str = (item == nullptr) ? this->def : item->value.value_or("");
  this->MakeValueValid(str);
  this->Write(object, str);
}
 
void ListSettingDesc::ParseValue(const IniItem *item, void *object) const
{
  const char *str = (item == nullptr) ? this->def : item->value.has_value() ? item->value->c_str() : nullptr;
  void *ptr = GetVariableAddress(object, this->save);
  if (!LoadIntList(str, ptr, this->save.length, GetVarMemType(this->save.conv))) {
    ErrorMessageData msg(STR_CONFIG_ERROR, STR_CONFIG_ERROR_ARRAY);
    msg.SetDParamStr(0, this->GetName());
    _settings_error_list.push_back(msg);
 
    /* Use default */
    LoadIntList(this->def, ptr, this->save.length, GetVarMemType(this->save.conv));
  }
}
 
static void IniSaveSettings(IniFile &ini, const SettingTable &settings_table, const char *grpname, void *object, bool)
{
  IniGroup *group_def = nullptr, *group;
  IniItem *item;
  char buf[512];
 
  for (auto &desc : settings_table) {
    const SettingDesc *sd = GetSettingDesc(desc);
    /* If the setting is not saved to the configuration
     * file, just continue with the next setting */
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    if (sd->flags & SF_NOT_IN_CONFIG) continue;
 
    /* XXX - wtf is this?? (group override?) */
    std::string s{ sd->GetName() };
    auto sc = s.find('.');
    if (sc != std::string::npos) {
      group = ini.GetGroup(s.substr(0, sc));
      s = s.substr(sc + 1);
    } else {
      if (group_def == nullptr) group_def = ini.GetGroup(grpname);
      group = group_def;
    }
 
    item = group->GetItem(s, true);
 
    if (!item->value.has_value() || !sd->IsSameValue(item, object)) {
      /* Value has changed, get the new value and put it into a buffer */
      sd->FormatValue(buf, lastof(buf), object);
 
      /* The value is different, that means we have to write it to the ini */
      item->value.emplace(buf);
    }
  }
}
 
void IntSettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  uint32 i = (uint32)this->Read(object);
  seprintf(buf, last, IsSignedVarMemType(this->save.conv) ? "%d" : "%u", i);
}
 
void BoolSettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  bool val = this->Read(object) != 0;
  strecpy(buf, val ? "true" : "false", last);
}
 
bool IntSettingDesc::IsSameValue(const IniItem *item, void *object) const
{
  int32 item_value = (int32)this->ParseValue(item->value->c_str());
  int32 object_value = this->Read(object);
  return item_value == object_value;
}
 
void StringSettingDesc::FormatValue(char *buf, const char *last, const void *object) const
{
  const std::string &str = this->Read(object);
  switch (GetVarMemType(this->save.conv)) {
    case SLE_VAR_STR: strecpy(buf, str.c_str(), last); break;
 
    case SLE_VAR_STRQ:
      if (str.empty()) {
        buf[0] = '\0';
      } else {
        seprintf(buf, last, "\"%s\"", str.c_str());
      }
      break;
 
    default: NOT_REACHED();
  }
}
 
bool StringSettingDesc::IsSameValue(const IniItem *item, void *object) const
{
  /* The ini parsing removes the quotes, which are needed to retain the spaces in STRQs,
   * so those values are always different in the parsed ini item than they should be. */
  if (GetVarMemType(this->save.conv) == SLE_VAR_STRQ) return false;
 
  const std::string &str = this->Read(object);
  return item->value->compare(str) == 0;
}
 
bool ListSettingDesc::IsSameValue(const IniItem *item, void *object) const
{
  /* Checking for equality is way more expensive than just writing the value. */
  return false;
}
 
static void IniLoadSettingList(IniFile &ini, const char *grpname, StringList &list)
{
  IniGroup *group = ini.GetGroup(grpname);
 
  if (group == nullptr) return;
 
  list.clear();
 
  for (const IniItem *item = group->item; item != nullptr; item = item->next) {
    if (!item->name.empty()) list.push_back(item->name);
  }
}
 
static void IniSaveSettingList(IniFile &ini, const char *grpname, StringList &list)
{
  IniGroup *group = ini.GetGroup(grpname);
 
  if (group == nullptr) return;
  group->Clear();
 
  for (const auto &iter : list) {
    group->GetItem(iter, true)->SetValue("");
  }
}
 
void IniLoadWindowSettings(IniFile &ini, const char *grpname, void *desc)
{
  IniLoadSettings(ini, _window_settings, grpname, desc, false);
}
 
void IniSaveWindowSettings(IniFile &ini, const char *grpname, void *desc)
{
  IniSaveSettings(ini, _window_settings, grpname, desc, false);
}
 
bool SettingDesc::IsEditable(bool do_command) const
{
  if (!do_command && !(this->flags & SF_NO_NETWORK_SYNC) && _networking && !_network_server && !(this->flags & SF_PER_COMPANY)) return false;
  if ((this->flags & SF_NETWORK_ONLY) && !_networking && _game_mode != GM_MENU) return false;
  if ((this->flags & SF_NO_NETWORK) && _networking) return false;
  if ((this->flags & SF_NEWGAME_ONLY) &&
      (_game_mode == GM_NORMAL ||
      (_game_mode == GM_EDITOR && !(this->flags & SF_SCENEDIT_TOO)))) return false;
  if ((this->flags & SF_SCENEDIT_ONLY) && _game_mode != GM_EDITOR) return false;
  return true;
}
 
SettingType SettingDesc::GetType() const
{
  if (this->flags & SF_PER_COMPANY) return ST_COMPANY;
  return (this->flags & SF_NOT_IN_SAVE) ? ST_CLIENT : ST_GAME;
}
 
const IntSettingDesc *SettingDesc::AsIntSetting() const
{
  assert(this->IsIntSetting());
  return static_cast<const IntSettingDesc *>(this);
}
 
const StringSettingDesc *SettingDesc::AsStringSetting() const
{
  assert(this->IsStringSetting());
  return static_cast<const StringSettingDesc *>(this);
}
 
void PrepareOldDiffCustom();
void HandleOldDiffCustom(bool savegame);
 
 
static void ValidateSettings()
{
  /* Do not allow a custom sea level with the original land generator. */
  if (_settings_newgame.game_creation.land_generator == LG_ORIGINAL &&
      _settings_newgame.difficulty.quantity_sea_lakes == CUSTOM_SEA_LEVEL_NUMBER_DIFFICULTY) {
    _settings_newgame.difficulty.quantity_sea_lakes = CUSTOM_SEA_LEVEL_MIN_PERCENTAGE;
  }
}
 
static void AILoadConfig(IniFile &ini, const char *grpname)
{
  IniGroup *group = ini.GetGroup(grpname);
  IniItem *item;
 
  /* Clean any configured AI */
  for (CompanyID c = COMPANY_FIRST; c < MAX_COMPANIES; c++) {
    AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME)->Change(nullptr);
  }
 
  /* If no group exists, return */
  if (group == nullptr) return;
 
  CompanyID c = COMPANY_FIRST;
  for (item = group->item; c < MAX_COMPANIES && item != nullptr; c++, item = item->next) {
    AIConfig *config = AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME);
 
    config->Change(item->name.c_str());
    if (!config->HasScript()) {
      if (item->name != "none") {
        Debug(script, 0, "The AI by the name '{}' was no longer found, and removed from the list.", item->name);
        continue;
      }
    }
    if (item->value.has_value()) config->StringToSettings(*item->value);
  }
}
 
static void GameLoadConfig(IniFile &ini, const char *grpname)
{
  IniGroup *group = ini.GetGroup(grpname);
  IniItem *item;
 
  /* Clean any configured GameScript */
  GameConfig::GetConfig(GameConfig::SSS_FORCE_NEWGAME)->Change(nullptr);
 
  /* If no group exists, return */
  if (group == nullptr) return;
 
  item = group->item;
  if (item == nullptr) return;
 
  GameConfig *config = GameConfig::GetConfig(AIConfig::SSS_FORCE_NEWGAME);
 
  config->Change(item->name.c_str());
  if (!config->HasScript()) {
    if (item->name != "none") {
      Debug(script, 0, "The GameScript by the name '{}' was no longer found, and removed from the list.", item->name);
      return;
    }
  }
  if (item->value.has_value()) config->StringToSettings(*item->value);
}
 
static int DecodeHexNibble(char c)
{
  if (c >= '0' && c <= '9') return c - '0';
  if (c >= 'A' && c <= 'F') return c + 10 - 'A';
  if (c >= 'a' && c <= 'f') return c + 10 - 'a';
  return -1;
}
 
static bool DecodeHexText(const char *pos, uint8 *dest, size_t dest_size)
{
  while (dest_size > 0) {
    int hi = DecodeHexNibble(pos[0]);
    int lo = (hi >= 0) ? DecodeHexNibble(pos[1]) : -1;
    if (lo < 0) return false;
    *dest++ = (hi << 4) | lo;
    pos += 2;
    dest_size--;
  }
  return *pos == '|';
}
 
static GRFConfig *GRFLoadConfig(IniFile &ini, const char *grpname, bool is_static)
{
  IniGroup *group = ini.GetGroup(grpname);
  IniItem *item;
  GRFConfig *first = nullptr;
  GRFConfig **curr = &first;
 
  if (group == nullptr) return nullptr;
 
  uint num_grfs = 0;
  for (item = group->item; item != nullptr; item = item->next) {
    GRFConfig *c = nullptr;
 
    uint8 grfid_buf[4], md5sum[16];
    const char *filename = item->name.c_str();
    bool has_grfid = false;
    bool has_md5sum = false;
 
    /* Try reading "<grfid>|" and on success, "<md5sum>|". */
    has_grfid = DecodeHexText(filename, grfid_buf, lengthof(grfid_buf));
    if (has_grfid) {
      filename += 1 + 2 * lengthof(grfid_buf);
      has_md5sum = DecodeHexText(filename, md5sum, lengthof(md5sum));
      if (has_md5sum) filename += 1 + 2 * lengthof(md5sum);
 
      uint32 grfid = grfid_buf[0] | (grfid_buf[1] << 8) | (grfid_buf[2] << 16) | (grfid_buf[3] << 24);
      if (has_md5sum) {
        const GRFConfig *s = FindGRFConfig(grfid, FGCM_EXACT, md5sum);
        if (s != nullptr) c = new GRFConfig(*s);
      }
      if (c == nullptr && !FioCheckFileExists(filename, NEWGRF_DIR)) {
        const GRFConfig *s = FindGRFConfig(grfid, FGCM_NEWEST_VALID);
        if (s != nullptr) c = new GRFConfig(*s);
      }
    }
    if (c == nullptr) c = new GRFConfig(filename);
 
    /* Parse parameters */
    if (item->value.has_value() && !item->value->empty()) {
      int count = ParseIntList(item->value->c_str(), c->param, lengthof(c->param));
      if (count < 0) {
        SetDParamStr(0, filename);
        ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_ARRAY, WL_CRITICAL);
        count = 0;
      }
      c->num_params = count;
    }
 
    /* Check if item is valid */
    if (!FillGRFDetails(c, is_static) || HasBit(c->flags, GCF_INVALID)) {
      if (c->status == GCS_NOT_FOUND) {
        SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_NOT_FOUND);
      } else if (HasBit(c->flags, GCF_UNSAFE)) {
        SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_UNSAFE);
      } else if (HasBit(c->flags, GCF_SYSTEM)) {
        SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_SYSTEM);
      } else if (HasBit(c->flags, GCF_INVALID)) {
        SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_INCOMPATIBLE);
      } else {
        SetDParam(1, STR_CONFIG_ERROR_INVALID_GRF_UNKNOWN);
      }
 
      SetDParamStr(0, StrEmpty(filename) ? item->name : filename);
      ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_INVALID_GRF, WL_CRITICAL);
      delete c;
      continue;
    }
 
    /* Check for duplicate GRFID (will also check for duplicate filenames) */
    bool duplicate = false;
    for (const GRFConfig *gc = first; gc != nullptr; gc = gc->next) {
      if (gc->ident.grfid == c->ident.grfid) {
        SetDParamStr(0, c->filename);
        SetDParamStr(1, gc->filename);
        ShowErrorMessage(STR_CONFIG_ERROR, STR_CONFIG_ERROR_DUPLICATE_GRFID, WL_CRITICAL);
        duplicate = true;
        break;
      }
    }
    if (duplicate) {
      delete c;
      continue;
    }
 
    if (is_static) {
      /* Mark file as static to avoid saving in savegame. */
      SetBit(c->flags, GCF_STATIC);
    } else if (++num_grfs > NETWORK_MAX_GRF_COUNT) {
      /* Check we will not load more non-static NewGRFs than allowed. This could trigger issues for game servers. */
      ShowErrorMessage(STR_CONFIG_ERROR, STR_NEWGRF_ERROR_TOO_MANY_NEWGRFS_LOADED, WL_CRITICAL);
      break;
    }
 
    /* Add item to list */
    *curr = c;
    curr = &c->next;
  }
 
  return first;
}
 
static IniFileVersion LoadVersionFromConfig(IniFile &ini)
{
  IniGroup *group = ini.GetGroup("version");
 
  auto version_number = group->GetItem("ini_version", false);
  /* Older ini-file versions don't have this key yet. */
  if (version_number == nullptr || !version_number->value.has_value()) return IFV_0;
 
  uint32 version = 0;
  std::from_chars(version_number->value->data(), version_number->value->data() + version_number->value->size(), version);
 
  return static_cast<IniFileVersion>(version);
}
 
static void AISaveConfig(IniFile &ini, const char *grpname)
{
  IniGroup *group = ini.GetGroup(grpname);
 
  if (group == nullptr) return;
  group->Clear();
 
  for (CompanyID c = COMPANY_FIRST; c < MAX_COMPANIES; c++) {
    AIConfig *config = AIConfig::GetConfig(c, AIConfig::SSS_FORCE_NEWGAME);
    const char *name;
    std::string value = config->SettingsToString();
 
    if (config->HasScript()) {
      name = config->GetName();
    } else {
      name = "none";
    }
 
    IniItem *item = new IniItem(group, name);
    item->SetValue(value);
  }
}
 
static void GameSaveConfig(IniFile &ini, const char *grpname)
{
  IniGroup *group = ini.GetGroup(grpname);
 
  if (group == nullptr) return;
  group->Clear();
 
  GameConfig *config = GameConfig::GetConfig(AIConfig::SSS_FORCE_NEWGAME);
  const char *name;
  std::string value = config->SettingsToString();
 
  if (config->HasScript()) {
    name = config->GetName();
  } else {
    name = "none";
  }
 
  IniItem *item = new IniItem(group, name);
  item->SetValue(value);
}
 
static void SaveVersionInConfig(IniFile &ini)
{
  IniGroup *group = ini.GetGroup("version");
  group->GetItem("version_string", true)->SetValue(_openttd_revision);
  group->GetItem("version_number", true)->SetValue(fmt::format("{:08X}", _openttd_newgrf_version));
  group->GetItem("ini_version", true)->SetValue(std::to_string(INIFILE_VERSION));
}
 
/* Save a GRF configuration to the given group name */
static void GRFSaveConfig(IniFile &ini, const char *grpname, const GRFConfig *list)
{
  ini.RemoveGroup(grpname);
  IniGroup *group = ini.GetGroup(grpname);
  const GRFConfig *c;
 
  for (c = list; c != nullptr; c = c->next) {
    /* Hex grfid (4 bytes in nibbles), "|", hex md5sum (16 bytes in nibbles), "|", file system path. */
    char key[4 * 2 + 1 + 16 * 2 + 1 + MAX_PATH];
    char params[512];
    GRFBuildParamList(params, c, lastof(params));
 
    char *pos = key + seprintf(key, lastof(key), "%08X|", BSWAP32(c->ident.grfid));
    pos = md5sumToString(pos, lastof(key), c->ident.md5sum);
    seprintf(pos, lastof(key), "|%s", c->filename);
    group->GetItem(key, true)->SetValue(params);
  }
}
 
/* Common handler for saving/loading variables to the configuration file */
static void HandleSettingDescs(IniFile &generic_ini, IniFile &private_ini, IniFile &secrets_ini, SettingDescProc *proc, SettingDescProcList *proc_list, bool only_startup = false)
{
  proc(generic_ini, _misc_settings, "misc", nullptr, only_startup);
#if defined(_WIN32) && !defined(DEDICATED)
  proc(generic_ini, _win32_settings, "win32", nullptr, only_startup);
#endif /* _WIN32 */
 
  /* The name "patches" is a fallback, as every setting should sets its own group. */
 
  for (auto &table : GenericSettingTables()) {
    proc(generic_ini, table, "patches", &_settings_newgame, only_startup);
  }
  for (auto &table : PrivateSettingTables()) {
    proc(private_ini, table, "patches", &_settings_newgame, only_startup);
  }
  for (auto &table : SecretSettingTables()) {
    proc(secrets_ini, table, "patches", &_settings_newgame, only_startup);
  }
 
  proc(generic_ini, _currency_settings, "currency", &_custom_currency, only_startup);
  proc(generic_ini, _company_settings, "company", &_settings_client.company, only_startup);
 
  if (!only_startup) {
    proc_list(private_ini, "server_bind_addresses", _network_bind_list);
    proc_list(private_ini, "servers", _network_host_list);
    proc_list(private_ini, "bans", _network_ban_list);
  }
}
 
static void RemoveEntriesFromIni(IniFile &ini, const SettingTable &table)
{
  for (auto &desc : table) {
    const SettingDesc *sd = GetSettingDesc(desc);
 
    /* For settings.xx.yy load the settings from [xx] yy = ? */
    std::string s{ sd->GetName() };
    auto sc = s.find('.');
    if (sc == std::string::npos) continue;
 
    IniGroup *group = ini.GetGroup(s.substr(0, sc));
    s = s.substr(sc + 1);
 
    group->RemoveItem(s);
  }
}
 
void LoadFromConfig(bool startup)
{
  ConfigIniFile generic_ini(_config_file);
  ConfigIniFile private_ini(_private_file);
  ConfigIniFile secrets_ini(_secrets_file);
 
  if (!startup) ResetCurrencies(false); // Initialize the array of currencies, without preserving the custom one
 
  IniFileVersion generic_version = LoadVersionFromConfig(generic_ini);
 
  /* Before the split of private/secrets, we have to look in the generic for these settings. */
  if (generic_version < IFV_PRIVATE_SECRETS) {
    HandleSettingDescs(generic_ini, generic_ini, generic_ini, IniLoadSettings, IniLoadSettingList, startup);
  } else {
    HandleSettingDescs(generic_ini, private_ini, secrets_ini, IniLoadSettings, IniLoadSettingList, startup);
  }
 
  /* Load basic settings only during bootstrap, load other settings not during bootstrap */
  if (!startup) {
    /* Convert network.server_advertise to network.server_game_type, but only if network.server_game_type is set to default value. */
    if (generic_version < IFV_GAME_TYPE) {
      if (_settings_client.network.server_game_type == SERVER_GAME_TYPE_LOCAL) {
        IniGroup *network = generic_ini.GetGroup("network", false);
        if (network != nullptr) {
          IniItem *server_advertise = network->GetItem("server_advertise", false);
          if (server_advertise != nullptr && server_advertise->value == "true") {
            _settings_client.network.server_game_type = SERVER_GAME_TYPE_PUBLIC;
          }
        }
      }
    }
 
    _grfconfig_newgame = GRFLoadConfig(generic_ini, "newgrf", false);
    _grfconfig_static  = GRFLoadConfig(generic_ini, "newgrf-static", true);
    AILoadConfig(generic_ini, "ai_players");
    GameLoadConfig(generic_ini, "game_scripts");
 
    PrepareOldDiffCustom();
    IniLoadSettings(generic_ini, _old_gameopt_settings, "gameopt", &_settings_newgame, false);
    HandleOldDiffCustom(false);
 
    ValidateSettings();
    DebugReconsiderSendRemoteMessages();
 
    /* Display scheduled errors */
    extern void ScheduleErrorMessage(ErrorList &datas);
    ScheduleErrorMessage(_settings_error_list);
    if (FindWindowById(WC_ERRMSG, 0) == nullptr) ShowFirstError();
  }
}
 
void SaveToConfig()
{
  ConfigIniFile generic_ini(_config_file);
  ConfigIniFile private_ini(_private_file);
  ConfigIniFile secrets_ini(_secrets_file);
 
  IniFileVersion generic_version = LoadVersionFromConfig(generic_ini);
 
  /* If we newly create the private/secrets file, add a dummy group on top
   * just so we can add a comment before it (that is how IniFile works).
   * This to explain what the file is about. After doing it once, never touch
   * it again, as otherwise we might be reverting user changes. */
  if (!private_ini.GetGroup("private", false)) private_ini.GetGroup("private")->comment = "; This file possibly contains private information which can identify you as person.\n";
  if (!secrets_ini.GetGroup("secrets", false)) secrets_ini.GetGroup("secrets")->comment = "; Do not share this file with others, not even if they claim to be technical support.\n; This file contains saved passwords and other secrets that should remain private to you!\n";
 
  if (generic_version == IFV_0) {
    /* Remove some obsolete groups. These have all been loaded into other groups. */
    generic_ini.RemoveGroup("patches");
    generic_ini.RemoveGroup("yapf");
    generic_ini.RemoveGroup("gameopt");
 
    /* Remove all settings from the generic ini that are now in the private ini. */
    generic_ini.RemoveGroup("server_bind_addresses");
    generic_ini.RemoveGroup("servers");
    generic_ini.RemoveGroup("bans");
    for (auto &table : PrivateSettingTables()) {
      RemoveEntriesFromIni(generic_ini, table);
    }
 
    /* Remove all settings from the generic ini that are now in the secrets ini. */
    for (auto &table : SecretSettingTables()) {
      RemoveEntriesFromIni(generic_ini, table);
    }
  }
 
  /* Remove network.server_advertise. */
  if (generic_version < IFV_GAME_TYPE) {
    IniGroup *network = generic_ini.GetGroup("network", false);
    if (network != nullptr) {
      network->RemoveItem("server_advertise");
    }
  }
 
  HandleSettingDescs(generic_ini, private_ini, secrets_ini, IniSaveSettings, IniSaveSettingList);
  GRFSaveConfig(generic_ini, "newgrf", _grfconfig_newgame);
  GRFSaveConfig(generic_ini, "newgrf-static", _grfconfig_static);
  AISaveConfig(generic_ini, "ai_players");
  GameSaveConfig(generic_ini, "game_scripts");
 
  SaveVersionInConfig(generic_ini);
  SaveVersionInConfig(private_ini);
  SaveVersionInConfig(secrets_ini);
 
  generic_ini.SaveToDisk(_config_file);
  private_ini.SaveToDisk(_private_file);
  secrets_ini.SaveToDisk(_secrets_file);
}
 
StringList GetGRFPresetList()
{
  StringList list;
 
  ConfigIniFile ini(_config_file);
  for (IniGroup *group = ini.group; group != nullptr; group = group->next) {
    if (group->name.compare(0, 7, "preset-") == 0) {
      list.push_back(group->name.substr(7));
    }
  }
 
  return list;
}
 
GRFConfig *LoadGRFPresetFromConfig(const char *config_name)
{
  size_t len = strlen(config_name) + 8;
  char *section = (char*)alloca(len);
  seprintf(section, section + len - 1, "preset-%s", config_name);
 
  ConfigIniFile ini(_config_file);
  GRFConfig *config = GRFLoadConfig(ini, section, false);
 
  return config;
}
 
void SaveGRFPresetToConfig(const char *config_name, GRFConfig *config)
{
  size_t len = strlen(config_name) + 8;
  char *section = (char*)alloca(len);
  seprintf(section, section + len - 1, "preset-%s", config_name);
 
  ConfigIniFile ini(_config_file);
  GRFSaveConfig(ini, section, config);
  ini.SaveToDisk(_config_file);
}
 
void DeleteGRFPresetFromConfig(const char *config_name)
{
  size_t len = strlen(config_name) + 8;
  char *section = (char*)alloca(len);
  seprintf(section, section + len - 1, "preset-%s", config_name);
 
  ConfigIniFile ini(_config_file);
  ini.RemoveGroup(section);
  ini.SaveToDisk(_config_file);
}
 
void IntSettingDesc::ChangeValue(const void *object, int32 newval) const
{
  int32 oldval = this->Read(object);
  this->MakeValueValid(newval);
  if (this->pre_check != nullptr && !this->pre_check(newval)) return;
  if (oldval == newval) return;
 
  this->Write(object, newval);
  if (this->post_callback != nullptr) this->post_callback(newval);
 
  if (this->flags & SF_NO_NETWORK) {
    GamelogStartAction(GLAT_SETTING);
    GamelogSetting(this->GetName(), oldval, newval);
    GamelogStopAction();
  }
 
  SetWindowClassesDirty(WC_GAME_OPTIONS);
 
  if (_save_config) SaveToConfig();
}
 
static const SettingDesc *GetSettingFromName(const std::string_view name, const SettingTable &settings)
{
  /* First check all full names */
  for (auto &desc : settings) {
    const SettingDesc *sd = GetSettingDesc(desc);
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    if (sd->GetName() == name) return sd;
  }
 
  /* Then check the shortcut variant of the name. */
  std::string short_name_suffix = std::string{ "." }.append(name);
  for (auto &desc : settings) {
    const SettingDesc *sd = GetSettingDesc(desc);
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    if (StrEndsWith(sd->GetName(), short_name_suffix)) return sd;
  }
 
  return nullptr;
}
 
void GetSaveLoadFromSettingTable(SettingTable settings, std::vector<SaveLoad> &saveloads)
{
  for (auto &desc : settings) {
    const SettingDesc *sd = GetSettingDesc(desc);
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    saveloads.push_back(sd->save);
  }
}
 
static const SettingDesc *GetCompanySettingFromName(std::string_view name)
{
  static const std::string_view company_prefix = "company.";
  if (StrStartsWith(name, company_prefix)) name.remove_prefix(company_prefix.size());
  return GetSettingFromName(name, _company_settings);
}
 
const SettingDesc *GetSettingFromName(const std::string_view name)
{
  for (auto &table : GenericSettingTables()) {
    auto sd = GetSettingFromName(name, table);
    if (sd != nullptr) return sd;
  }
  for (auto &table : PrivateSettingTables()) {
    auto sd = GetSettingFromName(name, table);
    if (sd != nullptr) return sd;
  }
  for (auto &table : SecretSettingTables()) {
    auto sd = GetSettingFromName(name, table);
    if (sd != nullptr) return sd;
  }
 
  return GetCompanySettingFromName(name);
}
 
CommandCost CmdChangeSetting(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
{
  if (text.empty()) return CMD_ERROR;
  const SettingDesc *sd = GetSettingFromName(text);
 
  if (sd == nullptr) return CMD_ERROR;
  if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) return CMD_ERROR;
  if (!sd->IsIntSetting()) return CMD_ERROR;
 
  if (!sd->IsEditable(true)) return CMD_ERROR;
 
  if (flags & DC_EXEC) {
    sd->AsIntSetting()->ChangeValue(&GetGameSettings(), p2);
  }
 
  return CommandCost();
}
 
CommandCost CmdChangeCompanySetting(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const std::string &text)
{
  if (text.empty()) return CMD_ERROR;
  const SettingDesc *sd = GetCompanySettingFromName(text.c_str());
 
  if (sd == nullptr) return CMD_ERROR;
  if (!sd->IsIntSetting()) return CMD_ERROR;
 
  if (flags & DC_EXEC) {
    sd->AsIntSetting()->ChangeValue(&Company::Get(_current_company)->settings, p2);
  }
 
  return CommandCost();
}
 
bool SetSettingValue(const IntSettingDesc *sd, int32 value, bool force_newgame)
{
  const IntSettingDesc *setting = sd->AsIntSetting();
  if ((setting->flags & SF_PER_COMPANY) != 0) {
    if (Company::IsValidID(_local_company) && _game_mode != GM_MENU) {
      return DoCommandP(0, 0, value, CMD_CHANGE_COMPANY_SETTING, nullptr, setting->GetName());
    }
 
    setting->ChangeValue(&_settings_client.company, value);
    return true;
  }
 
  /* If an item is company-based, we do not send it over the network
   * (if any) to change. Also *hack*hack* we update the _newgame version
   * of settings because changing a company-based setting in a game also
   * changes its defaults. At least that is the convention we have chosen */
  if (setting->flags & SF_NO_NETWORK_SYNC) {
    if (_game_mode != GM_MENU) {
      setting->ChangeValue(&_settings_newgame, value);
    }
    setting->ChangeValue(&GetGameSettings(), value);
    return true;
  }
 
  if (force_newgame) {
    setting->ChangeValue(&_settings_newgame, value);
    return true;
  }
 
  /* send non-company-based settings over the network */
  if (!_networking || (_networking && _network_server)) {
    return DoCommandP(0, 0, value, CMD_CHANGE_SETTING, nullptr, setting->GetName());
  }
  return false;
}
 
void SetDefaultCompanySettings(CompanyID cid)
{
  Company *c = Company::Get(cid);
  for (auto &desc : _company_settings) {
    const IntSettingDesc *int_setting = GetSettingDesc(desc)->AsIntSetting();
    int_setting->MakeValueValidAndWrite(&c->settings, int_setting->def);
  }
}
 
void SyncCompanySettings()
{
  const void *old_object = &Company::Get(_current_company)->settings;
  const void *new_object = &_settings_client.company;
  for (auto &desc : _company_settings) {
    const SettingDesc *sd = GetSettingDesc(desc);
    uint32 old_value = (uint32)sd->AsIntSetting()->Read(new_object);
    uint32 new_value = (uint32)sd->AsIntSetting()->Read(old_object);
    if (old_value != new_value) NetworkSendCommand(0, 0, new_value, CMD_CHANGE_COMPANY_SETTING, nullptr, sd->GetName(), _local_company);
  }
}
 
bool SetSettingValue(const StringSettingDesc *sd, std::string value, bool force_newgame)
{
  assert(sd->flags & SF_NO_NETWORK_SYNC);
 
  if (GetVarMemType(sd->save.conv) == SLE_VAR_STRQ && value.compare("(null)") == 0) {
    value.clear();
  }
 
  const void *object = (_game_mode == GM_MENU || force_newgame) ? &_settings_newgame : &_settings_game;
  sd->AsStringSetting()->ChangeValue(object, value);
  return true;
}
 
void StringSettingDesc::ChangeValue(const void *object, std::string &newval) const
{
  this->MakeValueValid(newval);
  if (this->pre_check != nullptr && !this->pre_check(newval)) return;
 
  this->Write(object, newval);
  if (this->post_callback != nullptr) this->post_callback(newval);
 
  if (_save_config) SaveToConfig();
}
 
/* Those 2 functions need to be here, else we have to make some stuff non-static
 * and besides, it is also better to keep stuff like this at the same place */
void IConsoleSetSetting(const char *name, const char *value, bool force_newgame)
{
  const SettingDesc *sd = GetSettingFromName(name);
  if (sd == nullptr) {
    IConsolePrint(CC_ERROR, "'{}' is an unknown setting.", name);
    return;
  }
 
  bool success = true;
  if (sd->IsStringSetting()) {
    success = SetSettingValue(sd->AsStringSetting(), value, force_newgame);
  } else if (sd->IsIntSetting()) {
    const IntSettingDesc *isd = sd->AsIntSetting();
    size_t val = isd->ParseValue(value);
    if (!_settings_error_list.empty()) {
      IConsolePrint(CC_ERROR, "'{}' is not a valid value for this setting.", value);
      _settings_error_list.clear();
      return;
    }
    success = SetSettingValue(isd, (int32)val, force_newgame);
  }
 
  if (!success) {
    if (_network_server) {
      IConsolePrint(CC_ERROR, "This command/variable is not available during network games.");
    } else {
      IConsolePrint(CC_ERROR, "This command/variable is only available to a network server.");
    }
  }
}
 
void IConsoleSetSetting(const char *name, int value)
{
  const SettingDesc *sd = GetSettingFromName(name);
  assert(sd != nullptr);
  SetSettingValue(sd->AsIntSetting(), value);
}
 
void IConsoleGetSetting(const char *name, bool force_newgame)
{
  const SettingDesc *sd = GetSettingFromName(name);
  if (sd == nullptr) {
    IConsolePrint(CC_ERROR, "'{}' is an unknown setting.", name);
    return;
  }
 
  const void *object = (_game_mode == GM_MENU || force_newgame) ? &_settings_newgame : &_settings_game;
 
  if (sd->IsStringSetting()) {
    IConsolePrint(CC_INFO, "Current value for '{}' is '{}'.", sd->GetName(), sd->AsStringSetting()->Read(object));
  } else if (sd->IsIntSetting()) {
    char value[20];
    sd->FormatValue(value, lastof(value), object);
    const IntSettingDesc *int_setting = sd->AsIntSetting();
    IConsolePrint(CC_INFO, "Current value for '{}' is '{}' (min: {}{}, max: {}).",
      sd->GetName(), value, (sd->flags & SF_GUI_0_IS_SPECIAL) ? "(0) " : "", int_setting->min, int_setting->max);
  }
}
 
static void IConsoleListSettingsTable(const SettingTable &table, const char *prefilter)
{
  for (auto &desc : table) {
    const SettingDesc *sd = GetSettingDesc(desc);
    if (!SlIsObjectCurrentlyValid(sd->save.version_from, sd->save.version_to)) continue;
    if (prefilter != nullptr && sd->GetName().find(prefilter) == std::string::npos) continue;
    char value[80];
    sd->FormatValue(value, lastof(value), &GetGameSettings());
    IConsolePrint(CC_DEFAULT, "{} = {}", sd->GetName(), value);
  }
}
 
void IConsoleListSettings(const char *prefilter)
{
  IConsolePrint(CC_HELP, "All settings with their current value:");
 
  for (auto &table : GenericSettingTables()) {
    IConsoleListSettingsTable(table, prefilter);
  }
  for (auto &table : PrivateSettingTables()) {
    IConsoleListSettingsTable(table, prefilter);
  }
  for (auto &table : SecretSettingTables()) {
    IConsoleListSettingsTable(table, prefilter);
  }
 
  IConsolePrint(CC_HELP, "Use 'setting' command to change a value.");
}