qzdoom/src/thingdef/thingdef_exp.cpp
Christoph Oelckers 3ce25bc348 - fixed: FxPreIncrDecr depended on undefined compiler behavior.
It could only work with right to left function argument processing, but with left to right it failed because the ParseExpressionA call altered sc.TokenType.
Note that with register-based arguments on 64 bit platforms this is a very critical issue!
2016-09-06 08:41:13 +02:00

696 lines
17 KiB
C++

/*
** thingdef_exp.cpp
**
** Expression parsing for DECORATE
**
**---------------------------------------------------------------------------
** Copyright 2005 Jan Cholasta
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions
** are met:
**
** 1. Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** 2. Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in the
** documentation and/or other materials provided with the distribution.
** 3. The name of the author may not be used to endorse or promote products
** derived from this software without specific prior written permission.
** 4. When not used as part of ZDoom or a ZDoom derivative, this code will be
** covered by the terms of the GNU General Public License as published by
** the Free Software Foundation; either version 2 of the License, or (at
** your option) any later version.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
** IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
** OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
** IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
** INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
** NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
** THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**---------------------------------------------------------------------------
**
*/
#include "actor.h"
#include "sc_man.h"
#include "tarray.h"
#include "templates.h"
#include "cmdlib.h"
#include "i_system.h"
#include "m_random.h"
#include "a_pickups.h"
#include "thingdef.h"
#include "p_lnspec.h"
#include "doomstat.h"
#include "thingdef_exp.h"
FRandom pr_exrandom ("EX_Random");
static FxExpression *ParseRandom(FScanner &sc, FName identifier, PClassActor *cls);
static FxExpression *ParseRandomPick(FScanner &sc, FName identifier, PClassActor *cls);
static FxExpression *ParseRandom2(FScanner &sc, PClassActor *cls);
static FxExpression *ParseAbs(FScanner &sc, PClassActor *cls);
static FxExpression *ParseAtan2(FScanner &sc, FName identifier, PClassActor *cls);
static FxExpression *ParseMinMax(FScanner &sc, FName identifier, PClassActor *cls);
static FxExpression *ParseClamp(FScanner &sc, PClassActor *cls);
//
// ParseExpression
// [GRB] Parses an expression and stores it into Expression array
// It's worth mentioning that this is using C++ operator precedence
//
static FxExpression *ParseExpressionM (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionL (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionK (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionJ (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionI (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionH (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionG (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionF (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionE (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionD (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionC (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionB (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpressionA (FScanner &sc, PClassActor *cls);
static FxExpression *ParseExpression0 (FScanner &sc, PClassActor *cls);
FxExpression *ParseExpression (FScanner &sc, PClassActor *cls, bool mustresolve)
{
FxExpression *data = ParseExpressionM (sc, cls);
if (mustresolve)
{
FCompileContext ctx(cls);
data = data->Resolve(ctx);
}
return data;
}
static FxExpression *ParseExpressionM (FScanner &sc, PClassActor *cls)
{
FxExpression *base = ParseExpressionL (sc, cls);
if (sc.CheckToken('?'))
{
FxExpression *truex = ParseExpressionM (sc, cls);
sc.MustGetToken(':');
FxExpression *falsex = ParseExpressionM (sc, cls);
return new FxConditional(base, truex, falsex);
}
else if (sc.CheckToken('='))
{
FxExpression *right = ParseExpressionM(sc, cls);
return new FxAssign(base, right);
}
else
{
FxBinary *exp;
FxAssignSelf *left = new FxAssignSelf(sc);
sc.GetToken();
switch (sc.TokenType)
{
case TK_AddEq:
exp = new FxAddSub('+', left, nullptr);
break;
case TK_SubEq:
exp = new FxAddSub('-', left, nullptr);
break;
case TK_MulEq:
exp = new FxMulDiv('*', left, nullptr);
break;
case TK_DivEq:
exp = new FxMulDiv('/', left, nullptr);
break;
case TK_ModEq:
exp = new FxMulDiv('%', left, nullptr);
break;
case TK_LShiftEq:
exp = new FxBinaryInt(TK_LShift, left, nullptr);
break;
case TK_RShiftEq:
exp = new FxBinaryInt(TK_RShift, left, nullptr);
break;
case TK_URShiftEq:
exp = new FxBinaryInt(TK_URShift, left, nullptr);
break;
case TK_AndEq:
exp = new FxBinaryInt('&', left, nullptr);
break;
case TK_XorEq:
exp = new FxBinaryInt('^', left, nullptr);
break;
case TK_OrEq:
exp = new FxBinaryInt('|', left, nullptr);
break;
default:
sc.UnGet();
delete left;
return base;
}
exp->right = ParseExpressionM(sc, cls);
FxAssign *ret = new FxAssign(base, exp);
left->Assignment = ret;
return ret;
}
}
static FxExpression *ParseExpressionL (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionK (sc, cls);
while (sc.CheckToken(TK_OrOr))
{
FxExpression *right = ParseExpressionK (sc, cls);
tmp = new FxBinaryLogical(TK_OrOr, tmp, right);
}
return tmp;
}
static FxExpression *ParseExpressionK (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionJ (sc, cls);
while (sc.CheckToken(TK_AndAnd))
{
FxExpression *right = ParseExpressionJ (sc, cls);
tmp = new FxBinaryLogical(TK_AndAnd, tmp, right);
}
return tmp;
}
static FxExpression *ParseExpressionJ (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionI (sc, cls);
while (sc.CheckToken('|'))
{
FxExpression *right = ParseExpressionI (sc, cls);
tmp = new FxBinaryInt('|', tmp, right);
}
return tmp;
}
static FxExpression *ParseExpressionI (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionH (sc, cls);
while (sc.CheckToken('^'))
{
FxExpression *right = ParseExpressionH (sc, cls);
tmp = new FxBinaryInt('^', tmp, right);
}
return tmp;
}
static FxExpression *ParseExpressionH (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionG (sc, cls);
while (sc.CheckToken('&'))
{
FxExpression *right = ParseExpressionG (sc, cls);
tmp = new FxBinaryInt('&', tmp, right);
}
return tmp;
}
static FxExpression *ParseExpressionG (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionF (sc, cls);
while (sc.GetToken() && (sc.TokenType == TK_Eq || sc.TokenType == TK_Neq))
{
int token = sc.TokenType;
FxExpression *right = ParseExpressionF (sc, cls);
tmp = new FxCompareEq(token, tmp, right);
}
if (!sc.End) sc.UnGet();
return tmp;
}
static FxExpression *ParseExpressionF (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionE (sc, cls);
while (sc.GetToken() && (sc.TokenType == '<' || sc.TokenType == '>' || sc.TokenType == TK_Leq || sc.TokenType == TK_Geq))
{
int token = sc.TokenType;
FxExpression *right = ParseExpressionE (sc, cls);
tmp = new FxCompareRel(token, tmp, right);
}
if (!sc.End) sc.UnGet();
return tmp;
}
static FxExpression *ParseExpressionE (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionD (sc, cls);
while (sc.GetToken() && (sc.TokenType == TK_LShift || sc.TokenType == TK_RShift || sc.TokenType == TK_URShift))
{
int token = sc.TokenType;
FxExpression *right = ParseExpressionD (sc, cls);
tmp = new FxBinaryInt(token, tmp, right);
}
if (!sc.End) sc.UnGet();
return tmp;
}
static FxExpression *ParseExpressionD (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionC (sc, cls);
while (sc.GetToken() && (sc.TokenType == '+' || sc.TokenType == '-'))
{
int token = sc.TokenType;
FxExpression *right = ParseExpressionC (sc, cls);
tmp = new FxAddSub(token, tmp, right);
}
if (!sc.End) sc.UnGet();
return tmp;
}
static FxExpression *ParseExpressionC (FScanner &sc, PClassActor *cls)
{
FxExpression *tmp = ParseExpressionB (sc, cls);
while (sc.GetToken() && (sc.TokenType == '*' || sc.TokenType == '/' || sc.TokenType == '%'))
{
int token = sc.TokenType;
FxExpression *right = ParseExpressionB (sc, cls);
tmp = new FxMulDiv(token, tmp, right);
}
if (!sc.End) sc.UnGet();
return tmp;
}
static FxExpression *ParseExpressionB (FScanner &sc, PClassActor *cls)
{
sc.GetToken();
int token = sc.TokenType;
switch(token)
{
case '~':
return new FxUnaryNotBitwise(ParseExpressionA (sc, cls));
case '!':
return new FxUnaryNotBoolean(ParseExpressionA (sc, cls));
case '-':
return new FxMinusSign(ParseExpressionA (sc, cls));
case '+':
return new FxPlusSign(ParseExpressionA (sc, cls));
case TK_Incr:
case TK_Decr:
return new FxPreIncrDecr(ParseExpressionA(sc, cls), token);
default:
sc.UnGet();
return ParseExpressionA (sc, cls);
}
}
//==========================================================================
//
// ParseExpressionB
//
//==========================================================================
static FxExpression *ParseExpressionA (FScanner &sc, PClassActor *cls)
{
FxExpression *base_expr = ParseExpression0 (sc, cls);
while(1)
{
FScriptPosition pos(sc);
#if 0
if (sc.CheckToken('.'))
{
if (sc.CheckToken(TK_Default))
{
sc.MustGetToken('.');
base_expr = new FxClassDefaults(base_expr, pos);
}
sc.MustGetToken(TK_Identifier);
FName FieldName = sc.String;
pos = sc;
/* later!
if (SC_CheckToken('('))
{
if (base_expr->IsDefaultObject())
{
SC_ScriptError("Cannot call methods for default.");
}
base_expr = ParseFunctionCall(base_expr, FieldName, false, false, pos);
}
else
*/
{
base_expr = new FxDotIdentifier(base_expr, FieldName, pos);
}
}
else
#endif
if (sc.CheckToken('['))
{
FxExpression *index = ParseExpressionM(sc, cls);
sc.MustGetToken(']');
base_expr = new FxArrayElement(base_expr, index);
}
else if (sc.CheckToken(TK_Incr))
{
return new FxPostIncrDecr(base_expr, TK_Incr);
}
else if (sc.CheckToken(TK_Decr))
{
return new FxPostIncrDecr(base_expr, TK_Decr);
}
else break;
}
return base_expr;
}
static FxExpression *ParseExpression0 (FScanner &sc, PClassActor *cls)
{
FScriptPosition scpos(sc);
if (sc.CheckToken('('))
{
FxExpression *data = ParseExpressionM (sc, cls);
sc.MustGetToken(')');
return data;
}
else if (sc.CheckToken(TK_True))
{
return new FxConstant(true, scpos);
}
else if (sc.CheckToken(TK_False))
{
return new FxConstant(false, scpos);
}
else if (sc.CheckToken(TK_IntConst))
{
return new FxConstant(sc.Number, scpos);
}
else if (sc.CheckToken(TK_FloatConst))
{
return new FxConstant(sc.Float, scpos);
}
else if (sc.CheckToken(TK_NameConst))
{
return new FxConstant(sc.Name, scpos);
}
else if (sc.CheckToken(TK_StringConst))
{
// String parameters are converted to names. Technically, this should be
// done at a higher level, as needed, but since no functions take string
// arguments and ACS_NamedExecuteWithResult/CallACS need names, this is
// a cheap way to get them working when people use "name" instead of 'name'.
return new FxConstant(FName(sc.String), scpos);
}
else if (sc.CheckToken(TK_Bool))
{
sc.MustGetToken('(');
FxExpression *exp = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
return new FxBoolCast(exp);
}
else if (sc.CheckToken(TK_Int))
{
sc.MustGetToken('(');
FxExpression *exp = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
return new FxIntCast(exp);
}
else if (sc.CheckToken(TK_Float))
{
sc.MustGetToken('(');
FxExpression *exp = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
return new FxFloatCast(exp);
}
else if (sc.CheckToken(TK_State))
{
sc.MustGetToken('(');
FxExpression *exp;
if (sc.CheckToken(TK_StringConst))
{
if (sc.String[0] == 0 || sc.Compare("None"))
{
exp = new FxConstant((FState*)nullptr, sc);
}
else
{
exp = new FxMultiNameState(sc.String, sc);
}
}
else
{
exp = new FxRuntimeStateIndex(ParseExpressionM(sc, cls));
}
sc.MustGetToken(')');
return exp;
}
else if (sc.CheckToken(TK_Identifier))
{
FName identifier = FName(sc.String);
FArgumentList *args;
PFunction *func;
switch (identifier)
{
case NAME_Random:
case NAME_FRandom:
return ParseRandom(sc, identifier, cls);
case NAME_RandomPick:
case NAME_FRandomPick:
return ParseRandomPick(sc, identifier, cls);
case NAME_Random2:
return ParseRandom2(sc, cls);
default:
if (cls != nullptr)
{
func = dyn_cast<PFunction>(cls->Symbols.FindSymbol(identifier, true));
// There is an action function ACS_NamedExecuteWithResult which must be ignored here for this to work.
if (func != nullptr && identifier != NAME_ACS_NamedExecuteWithResult)
{
args = new FArgumentList;
if (sc.CheckToken('('))
{
sc.UnGet();
ParseFunctionParameters(sc, cls, *args, func, "", nullptr);
}
if (args->Size() == 0)
{
delete args;
args = nullptr;
}
return new FxVMFunctionCall(func, args, sc);
}
}
break;
}
if (sc.CheckToken('('))
{
switch (identifier)
{
case NAME_Min:
case NAME_Max:
return ParseMinMax(sc, identifier, cls);
case NAME_Clamp:
return ParseClamp(sc, cls);
case NAME_Abs:
return ParseAbs(sc, cls);
case NAME_ATan2:
case NAME_VectorAngle:
return ParseAtan2(sc, identifier, cls);
default:
args = new FArgumentList;
try
{
if (!sc.CheckToken(')'))
{
do
{
args->Push(ParseExpressionM (sc, cls));
}
while (sc.CheckToken(','));
sc.MustGetToken(')');
}
return new FxFunctionCall(NULL, identifier, args, sc);
}
catch (...)
{
delete args;
throw;
}
break;
}
}
else
{
return new FxIdentifier(identifier, sc);
}
}
else
{
FString tokname = sc.TokenName(sc.TokenType, sc.String);
sc.ScriptError ("Unexpected token %s", tokname.GetChars());
}
return NULL;
}
static FRandom *ParseRNG(FScanner &sc)
{
FRandom *rng;
if (sc.CheckToken('['))
{
sc.MustGetToken(TK_Identifier);
rng = FRandom::StaticFindRNG(sc.String);
sc.MustGetToken(']');
}
else
{
rng = &pr_exrandom;
}
return rng;
}
static FxExpression *ParseRandom(FScanner &sc, FName identifier, PClassActor *cls)
{
FRandom *rng = ParseRNG(sc);
sc.MustGetToken('(');
FxExpression *min = ParseExpressionM (sc, cls);
sc.MustGetToken(',');
FxExpression *max = ParseExpressionM (sc, cls);
sc.MustGetToken(')');
if (identifier == NAME_Random)
{
return new FxRandom(rng, min, max, sc);
}
else
{
return new FxFRandom(rng, min, max, sc);
}
}
static FxExpression *ParseRandomPick(FScanner &sc, FName identifier, PClassActor *cls)
{
bool floaty = identifier == NAME_FRandomPick;
FRandom *rng;
TArray<FxExpression*> list;
list.Clear();
int index = 0;
rng = ParseRNG(sc);
sc.MustGetToken('(');
for (;;)
{
FxExpression *expr = ParseExpressionM(sc, cls);
list.Push(expr);
if (sc.CheckToken(')'))
break;
sc.MustGetToken(',');
}
return new FxRandomPick(rng, list, floaty, sc);
}
static FxExpression *ParseRandom2(FScanner &sc, PClassActor *cls)
{
FRandom *rng = ParseRNG(sc);
FxExpression *mask = NULL;
sc.MustGetToken('(');
if (!sc.CheckToken(')'))
{
mask = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
}
return new FxRandom2(rng, mask, sc);
}
static FxExpression *ParseAbs(FScanner &sc, PClassActor *cls)
{
FxExpression *x = ParseExpressionM (sc, cls);
sc.MustGetToken(')');
return new FxAbs(x);
}
static FxExpression *ParseAtan2(FScanner &sc, FName identifier, PClassActor *cls)
{
FxExpression *a = ParseExpressionM(sc, cls);
sc.MustGetToken(',');
FxExpression *b = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
return identifier == NAME_ATan2 ? new FxATan2(a, b, sc) : new FxATan2(b, a, sc);
}
static FxExpression *ParseMinMax(FScanner &sc, FName identifier, PClassActor *cls)
{
TArray<FxExpression*> list;
for (;;)
{
FxExpression *expr = ParseExpressionM(sc, cls);
list.Push(expr);
if (sc.CheckToken(')'))
break;
sc.MustGetToken(',');
}
return new FxMinMax(list, identifier, sc);
}
static FxExpression *ParseClamp(FScanner &sc, PClassActor *cls)
{
FxExpression *src = ParseExpressionM(sc, cls);
sc.MustGetToken(',');
FxExpression *min = ParseExpressionM(sc, cls);
sc.MustGetToken(',');
FxExpression *max = ParseExpressionM(sc, cls);
sc.MustGetToken(')');
// Build clamp(a,x,y) as min(max(a,x),y)
TArray<FxExpression *> list(2);
list.Reserve(2);
list[0] = src;
list[1] = min;
FxExpression *maxexpr = new FxMinMax(list, NAME_Max, sc);
list[0] = maxexpr;
list[1] = max;
return new FxMinMax(list, NAME_Min, sc);
}