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Diffstat (limited to 'slideshow/source/engine/smilfunctionparser.cxx')
| -rw-r--r-- | slideshow/source/engine/smilfunctionparser.cxx | 628 |
1 files changed, 628 insertions, 0 deletions
diff --git a/slideshow/source/engine/smilfunctionparser.cxx b/slideshow/source/engine/smilfunctionparser.cxx new file mode 100644 index 000000000..06a2b9639 --- /dev/null +++ b/slideshow/source/engine/smilfunctionparser.cxx @@ -0,0 +1,628 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * This file incorporates work covered by the following license notice: + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed + * with this work for additional information regarding copyright + * ownership. The ASF licenses this file to you under the Apache + * License, Version 2.0 (the "License"); you may not use this file + * except in compliance with the License. You may obtain a copy of + * the License at http://www.apache.org/licenses/LICENSE-2.0 . + */ + + +#include <tools/diagnose_ex.h> + +#include <slideshowexceptions.hxx> +#include <smilfunctionparser.hxx> +#include <expressionnodefactory.hxx> + +#include <rtl/ustring.hxx> +#include <sal/log.hxx> + +// Makes parser a static resource, +// we're synchronized externally. +// But watch out, the parser might have +// state not visible to this code! +#define BOOST_SPIRIT_SINGLE_GRAMMAR_INSTANCE + +#if defined(DBG_UTIL) +#define BOOST_SPIRIT_DEBUG +#endif +#include <boost/spirit/include/classic_core.hpp> + +#include <iostream> +#include <functional> +#include <algorithm> +#include <stack> + + +/* Implementation of SmilFunctionParser class */ + +namespace slideshow::internal +{ + namespace + { + typedef const char* StringIteratorT; + + struct ParserContext + { + typedef ::std::stack< std::shared_ptr<ExpressionNode> > OperandStack; + + // stores a stack of not-yet-evaluated operands. This is used + // by the operators (i.e. '+', '*', 'sin' etc.) to pop their + // arguments from. If all arguments to an operator are constant, + // the operator pushes a precalculated result on the stack, and + // a composite ExpressionNode otherwise. + OperandStack maOperandStack; + + // bounds of the shape this expression is associated with + ::basegfx::B2DRectangle maShapeBounds; + + // when true, enable usage of time-dependent variable '$' + // in expressions + bool mbParseAnimationFunction; + }; + + typedef ::std::shared_ptr< ParserContext > ParserContextSharedPtr; + + + template< typename Generator > class ShapeBoundsFunctor + { + public: + ShapeBoundsFunctor( Generator aGenerator, + const ParserContextSharedPtr& rContext ) : + maGenerator( aGenerator ), + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "ShapeBoundsFunctor::ShapeBoundsFunctor(): Invalid context" ); + } + + void operator()( StringIteratorT, StringIteratorT ) const + { + mpContext->maOperandStack.push( + ExpressionNodeFactory::createConstantValueExpression( + maGenerator( mpContext->maShapeBounds ) ) ); + } + + private: + Generator maGenerator; + ParserContextSharedPtr mpContext; + }; + + template< typename Generator > ShapeBoundsFunctor< Generator > + makeShapeBoundsFunctor( const Generator& rGenerator, + const ParserContextSharedPtr& rContext ) + { + return ShapeBoundsFunctor<Generator>(rGenerator, rContext); + } + + /** Generate apriori constant value + */ + class ConstantFunctor + { + public: + ConstantFunctor( double rValue, + const ParserContextSharedPtr& rContext ) : + mnValue( rValue ), + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "ConstantFunctor::ConstantFunctor(): Invalid context" ); + } + + void operator()( StringIteratorT, StringIteratorT ) const + { + mpContext->maOperandStack.push( + ExpressionNodeFactory::createConstantValueExpression( mnValue ) ); + } + + private: + const double mnValue; + ParserContextSharedPtr mpContext; + }; + + /** Generate parse-dependent-but-then-constant value + */ + class DoubleConstantFunctor + { + public: + explicit DoubleConstantFunctor( const ParserContextSharedPtr& rContext ) : + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "DoubleConstantFunctor::DoubleConstantFunctor(): Invalid context" ); + } + + void operator()( double n ) const + { + // push constant value expression to the stack + mpContext->maOperandStack.push( + ExpressionNodeFactory::createConstantValueExpression( n ) ); + } + + private: + ParserContextSharedPtr mpContext; + }; + + /** Generate special t value expression node + */ + class ValueTFunctor + { + public: + explicit ValueTFunctor( const ParserContextSharedPtr& rContext ) : + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "ValueTFunctor::ValueTFunctor(): Invalid context" ); + } + + void operator()( StringIteratorT, StringIteratorT ) const + { + if( !mpContext->mbParseAnimationFunction ) + { + SAL_WARN("slideshow", "ValueTFunctor::operator(): variable encountered, but we're not parsing a function here" ); + throw ParseError(); + } + + // push special t value expression to the stack + mpContext->maOperandStack.push( + ExpressionNodeFactory::createValueTExpression() ); + } + + private: + ParserContextSharedPtr mpContext; + }; + + template< typename Functor > class UnaryFunctionFunctor + { + private: + /** ExpressionNode implementation for unary + function over one ExpressionNode + */ + class UnaryFunctionExpression : public ExpressionNode + { + public: + UnaryFunctionExpression( const Functor& rFunctor, + const std::shared_ptr<ExpressionNode>& rArg ) : + maFunctor( rFunctor ), + mpArg( rArg ) + { + } + + virtual double operator()( double t ) const override + { + return maFunctor( (*mpArg)(t) ); + } + + virtual bool isConstant() const override + { + return mpArg->isConstant(); + } + + private: + Functor maFunctor; + std::shared_ptr<ExpressionNode> mpArg; + }; + + public: + UnaryFunctionFunctor( const Functor& rFunctor, + const ParserContextSharedPtr& rContext ) : + maFunctor( rFunctor ), + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "UnaryFunctionFunctor::UnaryFunctionFunctor(): Invalid context" ); + } + + void operator()( StringIteratorT, StringIteratorT ) const + { + ParserContext::OperandStack& rNodeStack( mpContext->maOperandStack ); + + if( rNodeStack.empty() ) + throw ParseError( "Not enough arguments for unary operator" ); + + // retrieve arguments + std::shared_ptr<ExpressionNode> pArg( std::move(rNodeStack.top()) ); + rNodeStack.pop(); + + // check for constness + if( pArg->isConstant() ) + { + rNodeStack.push( + ExpressionNodeFactory::createConstantValueExpression( + maFunctor( (*pArg)(0.0) ) ) ); + } + else + { + // push complex node, that calcs the value on demand + rNodeStack.push( + std::make_shared<UnaryFunctionExpression>( + maFunctor, + pArg ) ); + } + } + + private: + Functor maFunctor; + ParserContextSharedPtr mpContext; + }; + + // TODO(Q2): Refactor makeUnaryFunctionFunctor, + // makeBinaryFunctionFunctor and the whole + // ExpressionNodeFactory, to use a generic + // makeFunctionFunctor template, which is overloaded for + // unary, binary, ternary, etc. function pointers. + template< typename Functor > UnaryFunctionFunctor<Functor> + makeUnaryFunctionFunctor( const Functor& rFunctor, + const ParserContextSharedPtr& rContext ) + { + return UnaryFunctionFunctor<Functor>( rFunctor, rContext ); + } + + // MSVC has problems instantiating above template function with plain function + // pointers (doesn't like the const reference there). Thus, provide it with + // a dedicated overload here. + UnaryFunctionFunctor< double (*)(double) > + makeUnaryFunctionFunctor( double (*pFunc)(double), + const ParserContextSharedPtr& rContext ) + { + return UnaryFunctionFunctor< double (*)(double) >( pFunc, rContext ); + } + + /** Implements a binary function over two ExpressionNodes + + @tpl Generator + Generator functor, to generate an ExpressionNode of + appropriate type + + */ + template< class Generator > class BinaryFunctionFunctor + { + public: + BinaryFunctionFunctor( const Generator& rGenerator, + const ParserContextSharedPtr& rContext ) : + maGenerator( rGenerator ), + mpContext( rContext ) + { + ENSURE_OR_THROW( mpContext, + "BinaryFunctionFunctor::BinaryFunctionFunctor(): Invalid context" ); + } + + void operator()( StringIteratorT, StringIteratorT ) const + { + ParserContext::OperandStack& rNodeStack( mpContext->maOperandStack ); + + if( rNodeStack.size() < 2 ) + throw ParseError( "Not enough arguments for binary operator" ); + + // retrieve arguments + std::shared_ptr<ExpressionNode> pSecondArg( std::move(rNodeStack.top()) ); + rNodeStack.pop(); + std::shared_ptr<ExpressionNode> pFirstArg( std::move(rNodeStack.top()) ); + rNodeStack.pop(); + + // create combined ExpressionNode + std::shared_ptr<ExpressionNode> pNode( maGenerator( pFirstArg, + pSecondArg ) ); + + assert(pSecondArg && pFirstArg); + + // check for constness + if (pFirstArg->isConstant() && pSecondArg->isConstant()) + { + // call the operator() at pNode, store result + // in constant value ExpressionNode. + rNodeStack.push( + ExpressionNodeFactory::createConstantValueExpression( + (*pNode)( 0.0 ) ) ); + } + else + { + // push complex node, that calcs the value on demand + rNodeStack.push( pNode ); + } + } + + private: + Generator maGenerator; + ParserContextSharedPtr mpContext; + }; + + template< typename Generator > BinaryFunctionFunctor<Generator> + makeBinaryFunctionFunctor( const Generator& rGenerator, + const ParserContextSharedPtr& rContext ) + { + return BinaryFunctionFunctor<Generator>( rGenerator, rContext ); + } + + + // Workaround for MSVC compiler anomaly (stack trashing) + + // The default ureal_parser_policies implementation of parse_exp + // triggers a really weird error in MSVC7 (Version 13.00.9466), in + // that the real_parser_impl::parse_main() call of parse_exp() + // overwrites the frame pointer _on the stack_ (EBP of the calling + // function gets overwritten while lying on the stack). + + // For the time being, our parser thus can only read the 1.0E10 + // notation, not the 1.0e10 one. + + // TODO(F1): Also handle the 1.0e10 case here. + template< typename T > struct custom_real_parser_policies : public ::boost::spirit::classic::ureal_parser_policies<T> + { + template< typename ScannerT > + static typename ::boost::spirit::classic::parser_result< ::boost::spirit::classic::chlit<>, ScannerT >::type + parse_exp(ScannerT& scan) + { + // as_lower_d somehow breaks MSVC7 + return ::boost::spirit::classic::ch_p('E').parse(scan); + } + }; + + /* This class implements the following grammar (more or + less literally written down below, only slightly + obfuscated by the parser actions): + + identifier = '$'|'pi'|'e'|'X'|'Y'|'Width'|'Height' + + function = 'abs'|'sqrt'|'sin'|'cos'|'tan'|'atan'|'acos'|'asin'|'exp'|'log' + + basic_expression = + number | + identifier | + function '(' additive_expression ')' | + '(' additive_expression ')' + + unary_expression = + '-' basic_expression | + basic_expression + + multiplicative_expression = + unary_expression ( ( '*' unary_expression )* | + ( '/' unary_expression )* ) + + additive_expression = + multiplicative_expression ( ( '+' multiplicative_expression )* | + ( '-' multiplicative_expression )* ) + + */ + class ExpressionGrammar : public ::boost::spirit::classic::grammar< ExpressionGrammar > + { + public: + /** Create an arithmetic expression grammar + + @param rParserContext + Contains context info for the parser + */ + explicit ExpressionGrammar( const ParserContextSharedPtr& rParserContext ) : + mpParserContext( rParserContext ) + { + } + + template< typename ScannerT > class definition + { + public: + // grammar definition + explicit definition( const ExpressionGrammar& self ) + { + using ::boost::spirit::classic::str_p; + using ::boost::spirit::classic::real_parser; + + identifier = + str_p( "$" )[ ValueTFunctor( self.getContext()) ] + | str_p( "pi" )[ ConstantFunctor(M_PI, self.getContext()) ] + | str_p( "e" )[ ConstantFunctor(M_E, self.getContext()) ] + | str_p( "x" )[ makeShapeBoundsFunctor(::std::mem_fn(&::basegfx::B2DRange::getCenterX),self.getContext()) ] + | str_p( "y" )[ makeShapeBoundsFunctor(::std::mem_fn(&::basegfx::B2DRange::getCenterY),self.getContext()) ] + | str_p( "width" )[ makeShapeBoundsFunctor(::std::mem_fn(&::basegfx::B2DRange::getWidth), self.getContext()) ] + | str_p( "height" )[ makeShapeBoundsFunctor(::std::mem_fn(&::basegfx::B2DRange::getHeight), self.getContext()) ] + ; + + unaryFunction = + (str_p( "abs" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&fabs, self.getContext()) ] + | (str_p( "sqrt" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&sqrt, self.getContext()) ] + | (str_p( "sin" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&sin, self.getContext()) ] + | (str_p( "cos" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&cos, self.getContext()) ] + | (str_p( "tan" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&tan, self.getContext()) ] + | (str_p( "atan" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&atan, self.getContext()) ] + | (str_p( "acos" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&acos, self.getContext()) ] + | (str_p( "asin" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&asin, self.getContext()) ] + | (str_p( "exp" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&exp, self.getContext()) ] + | (str_p( "log" ) >> '(' >> additiveExpression >> ')' )[ makeUnaryFunctionFunctor(&log, self.getContext()) ] + ; + + binaryFunction = + (str_p( "min" ) >> '(' >> additiveExpression >> ',' >> additiveExpression >> ')' )[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createMinExpression, self.getContext()) ] + | (str_p( "max" ) >> '(' >> additiveExpression >> ',' >> additiveExpression >> ')' )[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createMaxExpression, self.getContext()) ] + ; + + basicExpression = + real_parser<double, custom_real_parser_policies<double> >()[ DoubleConstantFunctor(self.getContext()) ] + | identifier + | unaryFunction + | binaryFunction + | '(' >> additiveExpression >> ')' + ; + + unaryExpression = + ('-' >> basicExpression)[ makeUnaryFunctionFunctor(::std::negate<double>(), self.getContext()) ] + | basicExpression + ; + + multiplicativeExpression = + unaryExpression + >> *( ('*' >> unaryExpression)[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createMultipliesExpression, self.getContext()) ] + | ('/' >> unaryExpression)[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createDividesExpression, self.getContext()) ] + ) + ; + + additiveExpression = + multiplicativeExpression + >> *( ('+' >> multiplicativeExpression)[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createPlusExpression, self.getContext()) ] + | ('-' >> multiplicativeExpression)[ makeBinaryFunctionFunctor(&ExpressionNodeFactory::createMinusExpression, self.getContext()) ] + ) + ; + + BOOST_SPIRIT_DEBUG_RULE(additiveExpression); + BOOST_SPIRIT_DEBUG_RULE(multiplicativeExpression); + BOOST_SPIRIT_DEBUG_RULE(unaryExpression); + BOOST_SPIRIT_DEBUG_RULE(basicExpression); + BOOST_SPIRIT_DEBUG_RULE(unaryFunction); + BOOST_SPIRIT_DEBUG_RULE(binaryFunction); + BOOST_SPIRIT_DEBUG_RULE(identifier); + } + + const ::boost::spirit::classic::rule< ScannerT >& start() const + { + return additiveExpression; + } + + private: + // the constituents of the Spirit arithmetic expression grammar. + // For the sake of readability, without 'ma' prefix. + ::boost::spirit::classic::rule< ScannerT > additiveExpression; + ::boost::spirit::classic::rule< ScannerT > multiplicativeExpression; + ::boost::spirit::classic::rule< ScannerT > unaryExpression; + ::boost::spirit::classic::rule< ScannerT > basicExpression; + ::boost::spirit::classic::rule< ScannerT > unaryFunction; + ::boost::spirit::classic::rule< ScannerT > binaryFunction; + ::boost::spirit::classic::rule< ScannerT > identifier; + }; + + const ParserContextSharedPtr& getContext() const + { + return mpParserContext; + } + + private: + ParserContextSharedPtr mpParserContext; // might get modified during parsing + }; + + const ParserContextSharedPtr& getParserContext() + { + static ParserContextSharedPtr lcl_parserContext = std::make_shared<ParserContext>(); + + // clear node stack (since we reuse the static object, that's + // the whole point here) + while( !lcl_parserContext->maOperandStack.empty() ) + lcl_parserContext->maOperandStack.pop(); + + return lcl_parserContext; + } + } + + std::shared_ptr<ExpressionNode> const & SmilFunctionParser::parseSmilValue( const OUString& rSmilValue, + const ::basegfx::B2DRectangle& rRelativeShapeBounds ) + { + // TODO(Q1): Check if a combination of the RTL_UNICODETOTEXT_FLAGS_* + // gives better conversion robustness here (we might want to map space + // etc. to ASCII space here) + const OString& rAsciiSmilValue( + OUStringToOString( rSmilValue, RTL_TEXTENCODING_ASCII_US ) ); + + StringIteratorT aStart( rAsciiSmilValue.getStr() ); + StringIteratorT aEnd( rAsciiSmilValue.getStr()+rAsciiSmilValue.getLength() ); + + // static parser context, because the actual + // Spirit parser is also a static object + ParserContextSharedPtr pContext = getParserContext(); + + pContext->maShapeBounds = rRelativeShapeBounds; + pContext->mbParseAnimationFunction = false; // parse with '$' disabled + + + ExpressionGrammar aExpressionGrammer( pContext ); + const ::boost::spirit::classic::parse_info<StringIteratorT> aParseInfo( + ::boost::spirit::classic::parse( aStart, + aEnd, + aExpressionGrammer, + ::boost::spirit::classic::space_p ) ); + +#if OSL_DEBUG_LEVEL > 0 + ::std::cout.flush(); // needed to keep stdout and cout in sync +#endif + + // input fully congested by the parser? + if( !aParseInfo.full ) + throw ParseError( "SmilFunctionParser::parseSmilValue(): string not fully parseable" ); + + // parser's state stack now must contain exactly _one_ ExpressionNode, + // which represents our formula. + if( pContext->maOperandStack.size() != 1 ) + throw ParseError( "SmilFunctionParser::parseSmilValue(): incomplete or empty expression" ); + + return pContext->maOperandStack.top(); + } + + std::shared_ptr<ExpressionNode> const & SmilFunctionParser::parseSmilFunction( const OUString& rSmilFunction, + const ::basegfx::B2DRectangle& rRelativeShapeBounds ) + { + // TODO(Q1): Check if a combination of the RTL_UNICODETOTEXT_FLAGS_* + // gives better conversion robustness here (we might want to map space + // etc. to ASCII space here) + const OString& rAsciiSmilFunction( + OUStringToOString( rSmilFunction, RTL_TEXTENCODING_ASCII_US ) ); + + StringIteratorT aStart( rAsciiSmilFunction.getStr() ); + StringIteratorT aEnd( rAsciiSmilFunction.getStr()+rAsciiSmilFunction.getLength() ); + + // static parser context, because the actual + // Spirit parser is also a static object + ParserContextSharedPtr pContext = getParserContext(); + + pContext->maShapeBounds = rRelativeShapeBounds; + pContext->mbParseAnimationFunction = true; // parse with '$' enabled + + + ExpressionGrammar aExpressionGrammer( pContext ); + const ::boost::spirit::classic::parse_info<StringIteratorT> aParseInfo( + ::boost::spirit::classic::parse( aStart, + aEnd, + aExpressionGrammer >> ::boost::spirit::classic::end_p, + ::boost::spirit::classic::space_p ) ); + +#if OSL_DEBUG_LEVEL > 0 + ::std::cout.flush(); // needed to keep stdout and cout in sync +#endif + // input fully congested by the parser? + if( !aParseInfo.full ) + throw ParseError( "SmilFunctionParser::parseSmilFunction(): string not fully parseable" ); + + // parser's state stack now must contain exactly _one_ ExpressionNode, + // which represents our formula. + if( pContext->maOperandStack.size() != 1 ) + throw ParseError( "SmilFunctionParser::parseSmilFunction(): incomplete or empty expression" ); + + return pContext->maOperandStack.top(); + } +} + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + +// debug hooks + +namespace boost +{ + +void sp_scalar_constructor_hook(void *) +{ +} + +void sp_scalar_destructor_hook(void *) +{ +} + +} + +#endif + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |