/*
* 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 tracerestrict.h Header file for Trace Restriction. */
#include "stdafx.h"
#include "tracerestrict.h"
#include "train.h"
#include "core/bitmath_func.hpp"
#include "core/pool_func.hpp"
#include "command_func.h"
#include "company_func.h"
#include "viewport_func.h"
#include "window_func.h"
#include "order_base.h"
#include "pathfinder/yapf/yapf_cache.h"
#include
/** Trace Restrict Data Storage Model Notes:
*
* Signals may have 0, 1 or 2 trace restrict programs attached to them,
* up to one for each track. Two-way signals share the same program.
*
* The mapping between signals and programs is defined in terms of
* TraceRestrictRefId to TraceRestrictProgramID,
* where TraceRestrictRefId is formed of the tile index and track,
* and TraceRestrictProgramID is an index into the program pool.
*
* If one or more mappings exist for a given signal tile, bit 12 of M3 will be set to 1.
* This is updated whenever mappings are added/removed for that tile. This is to avoid
* needing to do a mapping lookup for the common case where there is no trace restrict
* program mapping for the given tile.
*
* Programs in the program pool are refcounted based on the number of mappings which exist.
* When this falls to 0, the program is deleted from the pool.
* If a program has a refcount greater than 1, it is a shared program.
*
* In all cases, an empty program is evaluated the same as the absence of a program.
* Therefore it is not necessary to store mappings to empty unshared programs.
* Any editing action which would otherwise result in a mapping to an empty program
* which has no other references, instead removes the mapping.
* This is not done for shared programs as this would delete the shared aspect whenever
* the program became empty.
*
* Empty programs with a refcount of 1 may still exist due to the edge case where:
* 1: There is an empty program with refcount 2
* 2: One of the two mappings is deleted
* Finding the other mapping would entail a linear search of the mappings, and there is little
* to be gained by doing so.
*/
/** Initialize the program pool */
TraceRestrictProgramPool _tracerestrictprogram_pool("TraceRestrictProgram");
INSTANTIATE_POOL_METHODS(TraceRestrictProgram)
/**
* TraceRestrictRefId --> TraceRestrictProgramID (Pool ID) mapping
* The indirection is mainly to enable shared programs
* TODO: use a more efficient container/indirection mechanism
*/
TraceRestrictMapping _tracerestrictprogram_mapping;
/// This should be used when all pools have been or are immediately about to be also cleared
/// Calling this at other times will leave dangling refcounts
void ClearTraceRestrictMapping() {
_tracerestrictprogram_mapping.clear();
}
enum TraceRestrictCondStackFlags {
TRCSF_DONE_IF = 1<<0, ///< The if/elif/else is "done", future elif/else branches will not be executed
TRCSF_SEEN_ELSE = 1<<1, ///< An else branch has been seen already, error if another is seen afterwards
TRCSF_ACTIVE = 1<<2, ///< The condition is currently active
TRCSF_PARENT_INACTIVE = 1<<3, ///< The parent condition is not active, thus this condition is also not active
};
DECLARE_ENUM_AS_BIT_SET(TraceRestrictCondStackFlags)
static void HandleCondition(std::vector &condstack, TraceRestrictCondFlags condflags, bool value)
{
if (condflags & TRCF_OR) {
assert(!condstack.empty());
if (condstack.back() & TRCSF_ACTIVE) {
// leave TRCSF_ACTIVE set
return;
}
}
if (condflags & (TRCF_OR | TRCF_ELSE)) {
assert(!condstack.empty());
if (condstack.back() & (TRCSF_DONE_IF | TRCSF_PARENT_INACTIVE)) {
condstack.back() &= ~TRCSF_ACTIVE;
return;
}
} else {
if (!condstack.empty() && !(condstack.back() & TRCSF_ACTIVE)) {
//this is a 'nested if', the 'parent if' is not active
condstack.push_back(TRCSF_PARENT_INACTIVE);
return;
}
condstack.push_back(static_cast(0));
}
if (value) {
condstack.back() |= TRCSF_DONE_IF | TRCSF_ACTIVE;
} else {
condstack.back() &= ~TRCSF_ACTIVE;
}
}
/// Test value op condvalue
static bool TestCondition(uint16 value, TraceRestrictCondOp condop, uint16 condvalue)
{
switch (condop) {
case TRCO_IS:
return value == condvalue;
case TRCO_ISNOT:
return value != condvalue;
case TRCO_LT:
return value < condvalue;
case TRCO_LTE:
return value <= condvalue;
case TRCO_GT:
return value > condvalue;
case TRCO_GTE:
return value >= condvalue;
default:
NOT_REACHED();
return false;
}
}
/// Test order condition
/// order may be NULL
static bool TestOrderCondition(const Order *order, TraceRestrictItem item)
{
bool result = false;
if (order) {
DestinationID condvalue = GetTraceRestrictValue(item);
switch (static_cast(GetTraceRestrictAuxField(item))) {
case TROCAF_STATION:
result = order->IsType(OT_GOTO_STATION) && order->GetDestination() == condvalue;
break;
case TROCAF_WAYPOINT:
result = order->IsType(OT_GOTO_WAYPOINT) && order->GetDestination() == condvalue;
break;
case OT_GOTO_DEPOT:
result = order->IsType(OT_GOTO_DEPOT) && order->GetDestination() == condvalue;
break;
default:
NOT_REACHED();
}
}
switch (GetTraceRestrictCondOp(item)) {
case TRCO_IS:
return result;
case TRCO_ISNOT:
return !result;
default:
NOT_REACHED();
return false;
}
}
/// Execute program on train and store results in out
void TraceRestrictProgram::Execute(const Train* v, TraceRestrictProgramResult& out) const
{
// static to avoid needing to re-alloc/resize on each execution
static std::vector condstack;
condstack.clear();
size_t size = this->items.size();
for (size_t i = 0; i < size; i++) {
TraceRestrictItem item = this->items[i];
TraceRestrictItemType type = GetTraceRestrictType(item);
if (IsTraceRestrictConditional(item)) {
TraceRestrictCondFlags condflags = GetTraceRestrictCondFlags(item);
TraceRestrictCondOp condop = GetTraceRestrictCondOp(item);
if (type == TRIT_COND_ENDIF) {
assert(!condstack.empty());
if (condflags & TRCF_ELSE) {
// else
assert(!(condstack.back() & TRCSF_SEEN_ELSE));
HandleCondition(condstack, condflags, true);
condstack.back() |= TRCSF_SEEN_ELSE;
} else {
// end if
condstack.pop_back();
}
} else {
uint16 condvalue = GetTraceRestrictValue(item);
bool result = false;
switch(type) {
case TRIT_COND_UNDEFINED:
result = false;
break;
case TRIT_COND_TRAIN_LENGTH:
result = TestCondition(CeilDiv(v->gcache.cached_total_length, TILE_SIZE), condop, condvalue);
break;
case TRIT_COND_MAX_SPEED:
result = TestCondition(v->GetDisplayMaxSpeed(), condop, condvalue);
break;
case TRIT_COND_CURRENT_ORDER:
result = TestOrderCondition(&(v->current_order), item);
break;
case TRIT_COND_NEXT_ORDER: {
if (v->orders.list == NULL) break;
if (v->orders.list->GetNumOrders() == 0) break;
const Order *current_order = v->GetOrder(v->cur_real_order_index);
for (const Order *order = v->orders.list->GetNext(current_order); order != current_order; order = v->orders.list->GetNext(order)) {
if (order->IsGotoOrder()) {
result = TestOrderCondition(order, item);
break;
}
}
break;
}
default:
NOT_REACHED();
}
HandleCondition(condstack, condflags, result);
}
} else {
if (condstack.empty() || condstack.back() & TRCSF_ACTIVE) {
switch(type) {
case TRIT_PF_DENY:
if (GetTraceRestrictValue(item)) {
out.flags &= ~TRPRF_DENY;
} else {
out.flags |= TRPRF_DENY;
}
break;
case TRIT_PF_PENALTY:
out.penalty += GetTraceRestrictValue(item);
break;
default:
NOT_REACHED();
}
}
}
}
assert(condstack.empty());
}
void TraceRestrictProgram::DecrementRefCount() {
assert(this->refcount > 0);
this->refcount--;
if (this->refcount == 0) {
delete this;
}
}
/// returns successful result if program seems OK
/// This only validates that conditional nesting is correct, at present
CommandCost TraceRestrictProgram::Validate(const std::vector &items) {
// static to avoid needing to re-alloc/resize on each execution
static std::vector condstack;
condstack.clear();
size_t size = items.size();
for (size_t i = 0; i < size; i++) {
TraceRestrictItem item = items[i];
TraceRestrictItemType type = GetTraceRestrictType(item);
if (IsTraceRestrictConditional(item)) {
TraceRestrictCondFlags condflags = GetTraceRestrictCondFlags(item);
if (type == TRIT_COND_ENDIF) {
if (condstack.empty()) {
return_cmd_error(STR_TRACE_RESTRICT_ERROR_VALIDATE_NO_IF); // else/endif with no starting if
}
if (condflags & TRCF_ELSE) {
// else
if (condstack.back() & TRCSF_SEEN_ELSE) {
return_cmd_error(STR_TRACE_RESTRICT_ERROR_VALIDATE_DUP_ELSE); // Two else clauses
}
HandleCondition(condstack, condflags, true);
condstack.back() |= TRCSF_SEEN_ELSE;
} else {
// end if
condstack.pop_back();
}
} else {
if (condflags & (TRCF_OR | TRCF_ELSE)) { // elif/orif
if (condstack.empty()) {
return_cmd_error(STR_TRACE_RESTRICT_ERROR_VALIDATE_ELIF_NO_IF); // Pre-empt assertions in HandleCondition
}
if (condstack.back() & TRCSF_SEEN_ELSE) {
return_cmd_error(STR_TRACE_RESTRICT_ERROR_VALIDATE_DUP_ELSE); // else clause followed by elif/orif
}
}
HandleCondition(condstack, condflags, true);
}
}
}
if(!condstack.empty()) {
return_cmd_error(STR_TRACE_RESTRICT_ERROR_VALIDATE_END_CONDSTACK);
}
return CommandCost();
}
void SetTraceRestrictValueDefault(TraceRestrictItem &item, TraceRestrictValueType value_type)
{
switch (value_type) {
case TRVT_NONE:
case TRVT_INT:
case TRVT_DENY:
case TRVT_SPEED:
SetTraceRestrictValue(item, 0);
SetTraceRestrictAuxField(item, 0);
break;
case TRVT_ORDER:
SetTraceRestrictValue(item, INVALID_STATION);
SetTraceRestrictAuxField(item, TROCAF_STATION);
break;
default:
NOT_REACHED();
break;
}
}
/// Set the type field of a TraceRestrictItem, and
/// reset any other fields which are no longer valid/meaningful
/// to sensible defaults
void SetTraceRestrictTypeAndNormalise(TraceRestrictItem &item, TraceRestrictItemType type)
{
if (item != 0) {
assert(GetTraceRestrictType(item) != TRIT_NULL);
assert(IsTraceRestrictConditional(item) == IsTraceRestrictTypeConditional(type));
}
assert(type != TRIT_NULL);
TraceRestrictTypePropertySet old_properties = GetTraceRestrictTypeProperties(item);
SetTraceRestrictType(item, type);
TraceRestrictTypePropertySet new_properties = GetTraceRestrictTypeProperties(item);
if (old_properties.cond_type != new_properties.cond_type ||
old_properties.value_type != new_properties.value_type) {
SetTraceRestrictCondOp(item, TRCO_IS);
SetTraceRestrictValueDefault(item, new_properties.value_type);
}
}
void SetIsSignalRestrictedBit(TileIndex t)
{
// First mapping for this tile, or later
TraceRestrictMapping::iterator lower_bound = _tracerestrictprogram_mapping.lower_bound(MakeTraceRestrictRefId(t, static_cast