/*
* 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 .
*/
/**
* @file game_info.cpp Functions to convert NetworkGameInfo to Packet and back.
*/
#include "../../stdafx.h"
#include "game_info.h"
#include "../../core/bitmath_func.hpp"
#include "../../company_base.h"
#include "../../timer/timer_game_calendar.h"
#include "../../debug.h"
#include "../../map_func.h"
#include "../../game/game.hpp"
#include "../../game/game_info.hpp"
#include "../../settings_type.h"
#include "../../string_func.h"
#include "../../rev.h"
#include "../network_func.h"
#include "../network.h"
#include "packet.h"
#include "../../safeguards.h"
/**
* How many hex digits of the git hash to include in network revision string.
* Determined as 10 hex digits + 2 characters for -g/-u/-m prefix.
*/
static const uint GITHASH_SUFFIX_LEN = 12;
NetworkServerGameInfo _network_game_info; ///< Information about our game.
/**
* Get the network version string used by this build.
* The returned string is guaranteed to be at most NETWORK_REVISON_LENGTH bytes including '\0' terminator.
*/
std::string_view GetNetworkRevisionString()
{
static std::string network_revision;
if (network_revision.empty()) {
network_revision = _openttd_revision;
if (_openttd_revision_tagged) {
/* Tagged; do not mangle further, though ensure it's not too long. */
if (network_revision.size() >= NETWORK_REVISION_LENGTH) network_revision.resize(NETWORK_REVISION_LENGTH - 1);
} else {
/* Not tagged; add the githash suffix while ensuring the string does not become too long. */
assert(_openttd_revision_modified < 3);
std::string githash_suffix = fmt::format("-{}{}", "gum"[_openttd_revision_modified], _openttd_revision_hash);
if (githash_suffix.size() > GITHASH_SUFFIX_LEN) githash_suffix.resize(GITHASH_SUFFIX_LEN);
/* Where did the hash start in the original string? Overwrite from that position, unless that would create a too long string. */
size_t hash_end = network_revision.find_last_of('-');
if (hash_end == std::string::npos) hash_end = network_revision.size();
if (hash_end + githash_suffix.size() >= NETWORK_REVISION_LENGTH) hash_end = NETWORK_REVISION_LENGTH - githash_suffix.size() - 1;
/* Replace the git hash in revision string. */
network_revision.replace(hash_end, std::string::npos, githash_suffix);
}
assert(network_revision.size() < NETWORK_REVISION_LENGTH); // size does not include terminator, constant does, hence strictly less than
Debug(net, 3, "Network revision name: {}", network_revision);
}
return network_revision;
}
/**
* Extract the git hash from the revision string.
* @param revision_string The revision string (formatted as DATE-BRANCH-GITHASH).
* @return The git has part of the revision.
*/
static std::string_view ExtractNetworkRevisionHash(std::string_view revision_string)
{
size_t index = revision_string.find_last_of('-');
if (index == std::string::npos) return {};
return revision_string.substr(index);
}
/**
* Checks whether the given version string is compatible with our version.
* First tries to match the full string, if that fails, attempts to compare just git hashes.
* @param other the version string to compare to
*/
bool IsNetworkCompatibleVersion(std::string_view other)
{
if (GetNetworkRevisionString() == other) return true;
/* If this version is tagged, then the revision string must be a complete match,
* since there is no git hash suffix in it.
* This is needed to avoid situations like "1.9.0-beta1" comparing equal to "2.0.0-beta1". */
if (_openttd_revision_tagged) return false;
std::string_view hash1 = ExtractNetworkRevisionHash(GetNetworkRevisionString());
std::string_view hash2 = ExtractNetworkRevisionHash(other);
return hash1 == hash2;
}
/**
* Check if an game entry is compatible with our client.
*/
void CheckGameCompatibility(NetworkGameInfo &ngi)
{
/* Check if we are allowed on this server based on the revision-check. */
ngi.version_compatible = IsNetworkCompatibleVersion(ngi.server_revision);
ngi.compatible = ngi.version_compatible;
/* Check if we have all the GRFs on the client-system too. */
for (const GRFConfig *c = ngi.grfconfig; c != nullptr; c = c->next) {
if (c->status == GCS_NOT_FOUND) ngi.compatible = false;
}
}
/**
* Fill a NetworkServerGameInfo structure with the static content, or things
* that are so static they can be updated on request from a settings change.
*/
void FillStaticNetworkServerGameInfo()
{
_network_game_info.use_password = !_settings_client.network.server_password.empty();
_network_game_info.start_date = TimerGameCalendar::ConvertYMDToDate(_settings_game.game_creation.starting_year, 0, 1);
_network_game_info.clients_max = _settings_client.network.max_clients;
_network_game_info.companies_max = _settings_client.network.max_companies;
_network_game_info.map_width = Map::SizeX();
_network_game_info.map_height = Map::SizeY();
_network_game_info.landscape = _settings_game.game_creation.landscape;
_network_game_info.dedicated = _network_dedicated;
_network_game_info.grfconfig = _grfconfig;
_network_game_info.server_name = _settings_client.network.server_name;
_network_game_info.server_revision = GetNetworkRevisionString();
}
/**
* Get the NetworkServerGameInfo structure with the latest information of the server.
* @return The current NetworkServerGameInfo.
*/
const NetworkServerGameInfo *GetCurrentNetworkServerGameInfo()
{
/* These variables are updated inside _network_game_info as if they are global variables:
* - clients_on
* - invite_code
* These don't need to be updated manually here.
*/
_network_game_info.companies_on = (byte)Company::GetNumItems();
_network_game_info.spectators_on = NetworkSpectatorCount();
_network_game_info.game_date = TimerGameCalendar::date;
return &_network_game_info;
}
/**
* Function that is called for every GRFConfig that is read when receiving
* a NetworkGameInfo. Only grfid and md5sum are set, the rest is zero. This
* function must set all appropriate fields. This GRF is later appended to
* the grfconfig list of the NetworkGameInfo.
* @param config The GRF to handle.
* @param name The name of the NewGRF, empty when unknown.
*/
static void HandleIncomingNetworkGameInfoGRFConfig(GRFConfig *config, std::string name)
{
/* Find the matching GRF file */
const GRFConfig *f = FindGRFConfig(config->ident.grfid, FGCM_EXACT, config->ident.md5sum);
if (f == nullptr) {
AddGRFTextToList(config->name, name.empty() ? GetString(STR_CONFIG_ERROR_INVALID_GRF_UNKNOWN) : name);
config->status = GCS_NOT_FOUND;
} else {
config->filename = f->filename;
config->name = f->name;
config->info = f->info;
config->url = f->url;
}
SetBit(config->flags, GCF_COPY);
}
/**
* Serializes the NetworkGameInfo struct to the packet.
* @param p the packet to write the data to.
* @param info the NetworkGameInfo struct to serialize from.
*/
void SerializeNetworkGameInfo(Packet *p, const NetworkServerGameInfo *info, bool send_newgrf_names)
{
p->Send_uint8 (NETWORK_GAME_INFO_VERSION);
/*
* Please observe the order.
* The parts must be read in the same order as they are sent!
*/
/* Update the documentation in game_info.h on changes
* to the NetworkGameInfo wire-protocol! */
/* NETWORK_GAME_INFO_VERSION = 6 */
p->Send_uint8(send_newgrf_names ? NST_GRFID_MD5_NAME : NST_GRFID_MD5);
/* NETWORK_GAME_INFO_VERSION = 5 */
GameInfo *game_info = Game::GetInfo();
p->Send_uint32(game_info == nullptr ? -1 : (uint32)game_info->GetVersion());
p->Send_string(game_info == nullptr ? "" : game_info->GetName());
/* NETWORK_GAME_INFO_VERSION = 4 */
{
/* Only send the GRF Identification (GRF_ID and MD5 checksum) of
* the GRFs that are needed, i.e. the ones that the server has
* selected in the NewGRF GUI and not the ones that are used due
* to the fact that they are in [newgrf-static] in openttd.cfg */
const GRFConfig *c;
uint count = 0;
/* Count number of GRFs to send information about */
for (c = info->grfconfig; c != nullptr; c = c->next) {
if (!HasBit(c->flags, GCF_STATIC)) count++;
}
p->Send_uint8 (count); // Send number of GRFs
/* Send actual GRF Identifications */
for (c = info->grfconfig; c != nullptr; c = c->next) {
if (HasBit(c->flags, GCF_STATIC)) continue;
SerializeGRFIdentifier(p, &c->ident);
if (send_newgrf_names) p->Send_string(c->GetName());
}
}
/* NETWORK_GAME_INFO_VERSION = 3 */
p->Send_uint32(info->game_date);
p->Send_uint32(info->start_date);
/* NETWORK_GAME_INFO_VERSION = 2 */
p->Send_uint8 (info->companies_max);
p->Send_uint8 (info->companies_on);
p->Send_uint8 (info->clients_max); // Used to be max-spectators
/* NETWORK_GAME_INFO_VERSION = 1 */
p->Send_string(info->server_name);
p->Send_string(info->server_revision);
p->Send_bool (info->use_password);
p->Send_uint8 (info->clients_max);
p->Send_uint8 (info->clients_on);
p->Send_uint8 (info->spectators_on);
p->Send_uint16(info->map_width);
p->Send_uint16(info->map_height);
p->Send_uint8 (info->landscape);
p->Send_bool (info->dedicated);
}
/**
* Deserializes the NetworkGameInfo struct from the packet.
* @param p the packet to read the data from.
* @param info the NetworkGameInfo to deserialize into.
*/
void DeserializeNetworkGameInfo(Packet *p, NetworkGameInfo *info, const GameInfoNewGRFLookupTable *newgrf_lookup_table)
{
static const TimerGameCalendar::Date MAX_DATE = TimerGameCalendar::ConvertYMDToDate(MAX_YEAR, 11, 31); // December is month 11
byte game_info_version = p->Recv_uint8();
NewGRFSerializationType newgrf_serialisation = NST_GRFID_MD5;
/*
* Please observe the order.
* The parts must be read in the same order as they are sent!
*/
/* Update the documentation in game_info.h on changes
* to the NetworkGameInfo wire-protocol! */
switch (game_info_version) {
case 6:
newgrf_serialisation = (NewGRFSerializationType)p->Recv_uint8();
if (newgrf_serialisation >= NST_END) return;
FALLTHROUGH;
case 5: {
info->gamescript_version = (int)p->Recv_uint32();
info->gamescript_name = p->Recv_string(NETWORK_NAME_LENGTH);
FALLTHROUGH;
}
case 4: {
/* Ensure that the maximum number of NewGRFs and the field in the network
* protocol are matched to eachother. If that is not the case anymore a
* check must be added to ensure the received data is still valid. */
static_assert(std::numeric_limits::max() == NETWORK_MAX_GRF_COUNT);
uint num_grfs = p->Recv_uint8();
GRFConfig **dst = &info->grfconfig;
for (uint i = 0; i < num_grfs; i++) {
NamedGRFIdentifier grf;
switch (newgrf_serialisation) {
case NST_GRFID_MD5:
DeserializeGRFIdentifier(p, &grf.ident);
break;
case NST_GRFID_MD5_NAME:
DeserializeGRFIdentifierWithName(p, &grf);
break;
case NST_LOOKUP_ID: {
if (newgrf_lookup_table == nullptr) return;
auto it = newgrf_lookup_table->find(p->Recv_uint32());
if (it == newgrf_lookup_table->end()) return;
grf = it->second;
break;
}
default:
NOT_REACHED();
}
GRFConfig *c = new GRFConfig();
c->ident = grf.ident;
HandleIncomingNetworkGameInfoGRFConfig(c, grf.name);
/* Append GRFConfig to the list */
*dst = c;
dst = &c->next;
}
FALLTHROUGH;
}
case 3:
info->game_date = Clamp(p->Recv_uint32(), 0, MAX_DATE);
info->start_date = Clamp(p->Recv_uint32(), 0, MAX_DATE);
FALLTHROUGH;
case 2:
info->companies_max = p->Recv_uint8 ();
info->companies_on = p->Recv_uint8 ();
p->Recv_uint8(); // Used to contain max-spectators.
FALLTHROUGH;
case 1:
info->server_name = p->Recv_string(NETWORK_NAME_LENGTH);
info->server_revision = p->Recv_string(NETWORK_REVISION_LENGTH);
if (game_info_version < 6) p->Recv_uint8 (); // Used to contain server-lang.
info->use_password = p->Recv_bool ();
info->clients_max = p->Recv_uint8 ();
info->clients_on = p->Recv_uint8 ();
info->spectators_on = p->Recv_uint8 ();
if (game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
info->game_date = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
info->start_date = p->Recv_uint16() + DAYS_TILL_ORIGINAL_BASE_YEAR;
}
if (game_info_version < 6) while (p->Recv_uint8() != 0) {} // Used to contain the map-name.
info->map_width = p->Recv_uint16();
info->map_height = p->Recv_uint16();
info->landscape = p->Recv_uint8 ();
info->dedicated = p->Recv_bool ();
if (info->landscape >= NUM_LANDSCAPE) info->landscape = 0;
}
}
/**
* Serializes the GRFIdentifier (GRF ID and MD5 checksum) to the packet
* @param p the packet to write the data to.
* @param grf the GRFIdentifier to serialize.
*/
void SerializeGRFIdentifier(Packet *p, const GRFIdentifier *grf)
{
uint j;
p->Send_uint32(grf->grfid);
for (j = 0; j < sizeof(grf->md5sum); j++) {
p->Send_uint8(grf->md5sum[j]);
}
}
/**
* Deserializes the GRFIdentifier (GRF ID and MD5 checksum) from the packet
* @param p the packet to read the data from.
* @param grf the GRFIdentifier to deserialize.
*/
void DeserializeGRFIdentifier(Packet *p, GRFIdentifier *grf)
{
uint j;
grf->grfid = p->Recv_uint32();
for (j = 0; j < sizeof(grf->md5sum); j++) {
grf->md5sum[j] = p->Recv_uint8();
}
}
/**
* Deserializes the NamedGRFIdentifier (GRF ID, MD5 checksum and name) from the packet
* @param p the packet to read the data from.
* @param grf the NamedGRFIdentifier to deserialize.
*/
void DeserializeGRFIdentifierWithName(Packet *p, NamedGRFIdentifier *grf)
{
DeserializeGRFIdentifier(p, &grf->ident);
grf->name = p->Recv_string(NETWORK_GRF_NAME_LENGTH);
}