blender/source/gameengine/Expressions/InputParser.cpp
Campbell Barton 3f2cb6e878 game engine python api
* removed macros that were not used much, some misleading.
* removed error string setting calls that overwrote the error set by PyArg_ParseTuple with a less useful one.
* use python macros Py_RETURN_NONE, Py_RETURN_TRUE, Py_RETURN_FALSE
2008-08-14 03:23:36 +00:00

656 lines
14 KiB
C++

// Parser.cpp: implementation of the CParser class.
/*
* Copyright (c) 1996-2000 Erwin Coumans <coockie@acm.org>
*
* Permission to use, copy, modify, distribute and sell this software
* and its documentation for any purpose is hereby granted without fee,
* provided that the above copyright notice appear in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation. Erwin Coumans makes no
* representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied warranty.
*
*/
#include <stdlib.h>
#include "MT_assert.h"
#include "Value.h"
#include "InputParser.h"
#include "ErrorValue.h"
#include "IntValue.h"
#include "StringValue.h"
#include "FloatValue.h"
#include "BoolValue.h"
#include "EmptyValue.h"
#include "ConstExpr.h"
#include "Operator2Expr.h"
#include "Operator1Expr.h"
#include "IdentifierExpr.h"
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
// this is disable at the moment, I expected a memleak from it, but the error-cleanup was the reason
// well, looks we don't need it anyway, until maybe the Curved Surfaces are integrated into CSG
// cool things like (IF(LOD==1,CCurvedValue,IF(LOD==2,CCurvedValue2)) etc...
#include "IfExpr.h"
#define NUM_PRIORITY 6
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
CParser::CParser() : m_identifierContext(NULL)
{
}
CParser::~CParser()
{
if (m_identifierContext)
m_identifierContext->Release();
}
void CParser::ScanError(STR_String str)
{
// sets the global variable errmsg to an errormessage with
// contents str, appending if it already exists
// AfxMessageBox("Parse Error:"+str,MB_ICONERROR);
if (errmsg)
errmsg = new COperator2Expr(VALUE_ADD_OPERATOR, errmsg, Error(str));
else
errmsg = Error(str);
sym = errorsym;
}
CExpression* CParser::Error(STR_String str)
{
// makes and returns a new CConstExpr filled with an CErrorValue
// with string str
// AfxMessageBox("Error:"+str,MB_ICONERROR);
return new CConstExpr(new CErrorValue(str));
}
void CParser::NextCh()
{
// sets the global variable ch to the next character, if it exists
// and increases the global variable chcount
chcount++;
if (chcount < text.Length())
ch = text[chcount];
else
ch = 0x00;
}
void CParser::TermChar(char c)
{
// generates an error if the next char isn't the specified char c,
// otherwise, skip the char
if(ch == c)
{
NextCh();
}
else
{
STR_String str;
str.Format("Warning: %c expected\ncontinuing without it", c);
trace(str);
}
}
void CParser::DigRep()
{
// changes the current character to the first character that
// isn't a decimal
while ((ch >= '0') && (ch <= '9'))
NextCh();
}
void CParser::CharRep()
{
// changes the current character to the first character that
// isn't an alphanumeric character
while (((ch >= '0') && (ch <= '9'))
|| ((ch >= 'a') && (ch <= 'z'))
|| ((ch >= 'A') && (ch <= 'Z'))
|| (ch == '.') || (ch == '_'))
NextCh();
}
void CParser::GrabString(int start)
{
// puts part of the input string into the global variable
// const_as_string, from position start, to position chchount
const_as_string = text.Mid(start, chcount-start);
}
void CParser::NextSym()
{
// sets the global variable sym to the next symbol, and
// if it is an operator
// sets the global variable opkind to the kind of operator
// if it is a constant
// sets the global variable constkind to the kind of operator
// if it is a reference to a cell
// sets the global variable cellcoord to the kind of operator
errmsg = NULL;
while(ch == ' ' || ch == 0x9)
NextCh();
switch(ch)
{
case '(':
sym = lbracksym; NextCh();
break;
case ')':
sym = rbracksym; NextCh();
break;
case ',':
sym = commasym; NextCh();
break;
case '+' :
sym = opsym; opkind = OPplus; NextCh();
break;
case '-' :
sym = opsym; opkind = OPminus; NextCh();
break;
case '*' :
sym = opsym; opkind = OPtimes; NextCh();
break;
case '/' :
sym = opsym; opkind = OPdivide; NextCh();
break;
case '&' :
sym = opsym; opkind = OPand; NextCh(); TermChar('&');
break;
case '|' :
sym = opsym; opkind = OPor; NextCh(); TermChar('|');
break;
case '=' :
sym = opsym; opkind = OPequal; NextCh(); TermChar('=');
break;
case '!' :
sym = opsym;
NextCh();
if (ch == '=')
{
opkind = OPunequal;
NextCh();
}
else
{
opkind = OPnot;
}
break;
case '>':
sym = opsym;
NextCh();
if (ch == '=')
{
opkind = OPgreaterequal;
NextCh();
}
else
{
opkind = OPgreater;
}
break;
case '<':
sym = opsym;
NextCh();
if (ch == '=') {
opkind = OPlessequal;
NextCh();
} else {
opkind = OPless;
}
break;
case '\"' : {
int start;
sym = constsym;
constkind = stringtype;
NextCh();
start = chcount;
while ((ch != '\"') && (ch != 0x0))
NextCh();
GrabString(start);
TermChar('\"'); // check for eol before '\"'
break;
}
case 0x0: sym = eolsym; break;
default:
{
int start;
start = chcount;
DigRep();
if ((start != chcount) || (ch == '.')) { // number
sym = constsym;
if (ch == '.') {
constkind = floattype;
NextCh();
DigRep();
}
else constkind = inttype;
if ((ch == 'e') || (ch == 'E')) {
int mark;
constkind = floattype;
NextCh();
if ((ch == '+') || (ch == '-')) NextCh();
mark = chcount;
DigRep();
if (mark == chcount) {
ScanError("Number expected after 'E'");
return;
}
}
GrabString(start);
} else if (((ch >= 'a') && (ch <= 'z'))
|| ((ch >= 'A') && (ch <= 'Z')))
{ // reserved word?
int start;
STR_String funstr;
start = chcount;
CharRep();
GrabString(start);
funstr = const_as_string;
funstr.Upper();
if (funstr == STR_String("SUM")) {
sym = sumsym;
}
else if (funstr == STR_String("NOT")) {
sym = opsym;
opkind = OPnot;
}
else if (funstr == STR_String("AND")) {
sym = opsym; opkind = OPand;
}
else if (funstr == STR_String("OR")) {
sym = opsym; opkind = OPor;
}
else if (funstr == STR_String("IF")) {
sym = ifsym;
} else if (funstr == STR_String("WHOMADE")) {
sym = whocodedsym;
} else if (funstr == STR_String("FALSE")) {
sym = constsym; constkind = booltype; boolvalue = false;
} else if (funstr == STR_String("TRUE")) {
sym = constsym; constkind = booltype; boolvalue = true;
} else {
sym = idsym;
//STR_String str;
//str.Format("'%s' makes no sense here", (const char*)funstr);
//ScanError(str);
}
} else { // unknown symbol
STR_String str;
str.Format("Unexpected character '%c'", ch);
NextCh();
ScanError(str);
return;
}
}
}
}
int CParser::MakeInt() {
// returns the integer representation of the value in the global
// variable const_as_string
// pre: const_as_string contains only numercal chars
return atoi(const_as_string);
}
STR_String CParser::Symbol2Str(int s) {
// returns a string representation of of symbol s,
// for use in Term when generating an error
switch(s) {
case errorsym: return "error";
case lbracksym: return "(";
case rbracksym: return ")";
case commasym: return ",";
case opsym: return "operator";
case constsym: return "constant";
case sumsym: return "SUM";
case ifsym: return "IF";
case whocodedsym: return "WHOMADE";
case eolsym: return "end of line";
case idsym: return "identifier";
default: return "unknown"; // should not happen
}
}
void CParser::Term(int s) {
// generates an error if the next symbol isn't the specified symbol s
// otherwise, skip the symbol
if(s == sym) NextSym();
else {
STR_String msg;
msg.Format("Warning: " + Symbol2Str(s) + " expected\ncontinuing without it");
// AfxMessageBox(msg,MB_ICONERROR);
trace(msg);
}
}
int CParser::Priority(int optorkind) {
// returns the priority of an operator
// higher number means higher priority
switch(optorkind) {
case OPor: return 1;
case OPand: return 2;
case OPgreater:
case OPless:
case OPgreaterequal:
case OPlessequal:
case OPequal:
case OPunequal: return 3;
case OPplus:
case OPminus: return 4;
case OPtimes:
case OPdivide: return 5;
}
MT_assert(false);
return 0; // should not happen
}
CExpression *CParser::Ex(int i) {
// parses an expression in the imput, starting at priority i, and
// returns an CExpression, containing the parsed input
CExpression *e1 = NULL, *e2 = NULL;
int opkind2;
if (i < NUM_PRIORITY) {
e1 = Ex(i + 1);
while ((sym == opsym) && (Priority(opkind) == i)) {
opkind2 = opkind;
NextSym();
e2 = Ex(i + 1);
switch(opkind2) {
case OPplus: e1 = new COperator2Expr(VALUE_ADD_OPERATOR,e1, e2); break;
case OPminus: e1 = new COperator2Expr(VALUE_SUB_OPERATOR,e1, e2); break;
case OPtimes: e1 = new COperator2Expr(VALUE_MUL_OPERATOR,e1, e2); break;
case OPdivide: e1 = new COperator2Expr(VALUE_DIV_OPERATOR,e1, e2); break;
case OPand: e1 = new COperator2Expr(VALUE_AND_OPERATOR,e1, e2); break;
case OPor: e1 = new COperator2Expr(VALUE_OR_OPERATOR,e1, e2); break;
case OPequal: e1 = new COperator2Expr(VALUE_EQL_OPERATOR,e1, e2); break;
case OPunequal: e1 = new COperator2Expr(VALUE_NEQ_OPERATOR,e1, e2); break;
case OPgreater: e1 = new COperator2Expr(VALUE_GRE_OPERATOR,e1, e2); break;
case OPless: e1 = new COperator2Expr(VALUE_LES_OPERATOR,e1, e2); break;
case OPgreaterequal: e1 = new COperator2Expr(VALUE_GEQ_OPERATOR,e1, e2); break;
case OPlessequal: e1 = new COperator2Expr(VALUE_LEQ_OPERATOR,e1, e2); break;
default: MT_assert(false); break; // should not happen
}
}
} else if (i == NUM_PRIORITY) {
if ((sym == opsym)
&& ( (opkind == OPminus) || (opkind == OPnot) || (opkind == OPplus) )
)
{
NextSym();
switch(opkind) {
/* +1 is also a valid number! */
case OPplus: e1 = new COperator1Expr(VALUE_POS_OPERATOR, Ex(NUM_PRIORITY)); break;
case OPminus: e1 = new COperator1Expr(VALUE_NEG_OPERATOR, Ex(NUM_PRIORITY)); break;
case OPnot: e1 = new COperator1Expr(VALUE_NOT_OPERATOR, Ex(NUM_PRIORITY)); break;
default: {
// should not happen
e1 = Error("operator +, - or ! expected");
}
}
}
else {
switch(sym) {
case constsym: {
switch(constkind) {
case booltype:
e1 = new CConstExpr(new CBoolValue(boolvalue));
break;
case inttype:
{
int temp;
temp = atoi(const_as_string);
e1 = new CConstExpr(new CIntValue(temp));
break;
}
case floattype:
{
double temp;
temp = atof(const_as_string);
e1 = new CConstExpr(new CFloatValue(temp));
break;
}
case stringtype:
e1 = new CConstExpr(new CStringValue(const_as_string,""));
break;
default :
MT_assert(false);
break;
}
NextSym();
break;
}
case lbracksym:
NextSym();
e1 = Ex(1);
Term(rbracksym);
break;
case ifsym:
{
CExpression *e3;
NextSym();
Term(lbracksym);
e1 = Ex(1);
Term(commasym);
e2 = Ex(1);
if (sym == commasym) {
NextSym();
e3 = Ex(1);
} else {
e3 = new CConstExpr(new CEmptyValue());
}
Term(rbracksym);
e1 = new CIfExpr(e1, e2, e3);
break;
}
case idsym:
{
e1 = new CIdentifierExpr(const_as_string,m_identifierContext);
NextSym();
break;
}
case errorsym:
{
MT_assert(!e1);
STR_String errtext="[no info]";
if (errmsg)
{
CValue* errmsgval = errmsg->Calculate();
errtext=errmsgval->GetText();
errmsgval->Release();
//e1 = Error(errmsg->Calculate()->GetText());//new CConstExpr(errmsg->Calculate());
if ( !(errmsg->Release()) )
{
errmsg=NULL;
} else {
// does this happen ?
MT_assert ("does this happen");
}
}
e1 = Error(errtext);
break;
}
default:
NextSym();
//return Error("Expression expected");
MT_assert(!e1);
e1 = Error("Expression expected");
}
}
}
return e1;
}
CExpression *CParser::Expr() {
// parses an expression in the imput, and
// returns an CExpression, containing the parsed input
return Ex(1);
}
CExpression* CParser::ProcessText
(STR_String intext) {
// and parses the string in intext and returns it.
CExpression* expr;
text = intext;
chcount = 0;
if (text.Length() == 0) {
return NULL;
}
ch = text[0];
/*if (ch != '=') {
expr = new CConstExpr(new CStringValue(text));
*dependant = deplist;
return expr;
} else
*/
// NextCh();
NextSym();
expr = Expr();
if (sym != eolsym) {
CExpression* oldexpr = expr;
expr = new COperator2Expr(VALUE_ADD_OPERATOR,
oldexpr, Error(STR_String("Extra characters after expression")));//new CConstExpr(new CErrorValue("Extra characters after expression")));
}
if (errmsg)
errmsg->Release();
return expr;
}
float CParser::GetFloat(STR_String txt)
{
// returns parsed text into a float
// empty string returns -1
// AfxMessageBox("parsed string="+txt);
CValue* val=NULL;
float result=-1;
// String tmpstr;
CExpression* expr = ProcessText(txt);
if (expr) {
val = expr->Calculate();
result=val->GetNumber();
val->Release();
expr->Release();
}
// tmpstr.Format("parseresult=%g",result);
// AfxMessageBox(tmpstr);
return result;
}
CValue* CParser::GetValue(STR_String txt, bool bFallbackToText)
{
// returns parsed text into a value,
// empty string returns NULL value !
// if bFallbackToText then unparsed stuff is put into text
CValue* result=NULL;
CExpression* expr = ProcessText(txt);
if (expr) {
result = expr->Calculate();
expr->Release();
}
if (result)
{
// if the parsed stuff lead to an errorvalue, don't return errors, just NULL
if (result->IsError()) {
result->Release();
result=NULL;
if (bFallbackToText) {
if (txt.Length()>0)
{
result = new CStringValue(txt,"");
}
}
}
}
return result;
}
void CParser::SetContext(CValue* context)
{
if (m_identifierContext)
{
m_identifierContext->Release();
}
m_identifierContext = context;
}
PyObject* CParserPyMake(PyObject* ignored,PyObject* args)
{
char* txt;
if (!PyArg_ParseTuple(args,"s",&txt))
return NULL;
CParser parser;
CExpression* expr = parser.ProcessText(txt);
CValue* val = expr->Calculate();
expr->Release();
return val;
}
static PyMethodDef CParserMethods[] =
{
{ "calc", CParserPyMake , METH_VARARGS},
{ NULL,NULL} // Sentinel
};
extern "C" {
void initExpressionModule(void)
{
Py_InitModule("Expression",CParserMethods);
}
}