X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Floader.h;h=7d5d8d9690dfd1c9460739e7a22332a26e6d5e42;hb=c4930d8d15a5a248ca921e0ed3f9bca8aa18b322;hp=2fe0292bff01d5a6cdbab98e387daf0bbfab309e;hpb=26ab6b6a9e1c1eae7190135d762df8b37c3c60f9;p=libs%2Fdatafile.git diff --git a/source/loader.h b/source/loader.h index 2fe0292..7d5d8d9 100644 --- a/source/loader.h +++ b/source/loader.h @@ -1,207 +1,307 @@ -/* -This file is part of libmspparser +/* $Id$ + +This file is part of libmspdatafile Copyright © 2006 Mikko Rasa, Mikkosoft Productions Distributed under the LGPL */ -#ifndef MSP_PARSER_LOADER_H_ -#define MSP_PARSER_LOADER_H_ +#ifndef MSP_DATAFILE_LOADER_H_ +#define MSP_DATAFILE_LOADER_H_ + +#include #include -#include +#include "error.h" #include "parser.h" #include "statement.h" #include "value.h" namespace Msp { -namespace Parser { +namespace DataFile { class Loader; class Statement; +/** +Base class for loader actions. +*/ class LoaderAction { public: + /** + Called when a statement is to be loaded. + */ virtual void execute(Loader &, const Statement &) const=0; virtual ~LoaderAction() { } protected: LoaderAction() { } }; + +/** +Loads a statement by calling a function that takes no arguments. +*/ template class LoaderFunc0: public LoaderAction { public: typedef void (L::*FuncType)(); - + LoaderFunc0(FuncType f): func(f) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=0) throw TypeError("Wrong number of arguments"); + if(st.args.size()!=0) throw TypeError(st.get_location()+": Wrong number of arguments"); (dynamic_cast(l).*func)(); }; private: FuncType func; }; + +/** +Loads a statement by calling a function that takes one argument. +*/ template class LoaderFunc1: public LoaderAction { public: typedef void (L::*FuncType)(A0); - + LoaderFunc1(FuncType f): func(f) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=1) throw TypeError("Wrong number of arguments"); + if(st.args.size()!=1) throw TypeError(st.get_location()+": Wrong number of arguments"); (dynamic_cast(l).*func)(st.args[0].get()); } private: FuncType func; }; + +/** +Loads a statement by calling a function that takes an array of values. +*/ +template +class LoaderFunc1 &>: public LoaderAction +{ +public: + typedef void (L::*FuncType)(const std::vector &); + + LoaderFunc1(FuncType f): func(f) { } + void execute(Loader &l, const Statement &st) const + { + std::vector values; + values.reserve(st.args.size()); + for(ValueArray::const_iterator i=st.args.begin(); i!=st.args.end(); ++i) + values.push_back(i->get()); + (dynamic_cast(l).*func)(values); + } +private: + FuncType func; +}; + + template class LoaderFunc2: public LoaderAction { public: typedef void (L::*FuncType)(A0, A1); - + LoaderFunc2(FuncType f): func(f) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=2) throw TypeError("Wrong number of arguments"); + if(st.args.size()!=2) throw TypeError(st.get_location()+": Wrong number of arguments"); (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get()); } private: FuncType func; }; + template class LoaderFunc3: public LoaderAction { public: typedef void (L::*FuncType)(A0, A1, A2); - + LoaderFunc3(FuncType f): func(f) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=3) throw TypeError("Wrong number of arguments"); + if(st.args.size()!=3) throw TypeError(st.get_location()+": Wrong number of arguments"); (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get(), st.args[2].get()); } private: FuncType func; }; + template class LoaderFunc4: public LoaderAction { public: typedef void (L::*FuncType)(A0, A1, A2, A3); - + LoaderFunc4(FuncType f): func(f) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=4) throw TypeError("Wrong number of arguments"); + if(st.args.size()!=4) throw TypeError(st.get_location()+": Wrong number of arguments"); (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get(), st.args[2].get(), st.args[3].get()); } private: FuncType func; }; -template -class LoadValue: public LoaderAction + +template +class LoadValue1: public LoaderAction { public: - typedef T L::*PointerType; - - LoadValue(PointerType p): ptr(p) { } + typedef T0 L::*Pointer0Type; + + LoadValue1(Pointer0Type p0): ptr0(p0) { } void execute(Loader &l, const Statement &st) const { - if(st.args.size()!=1) throw TypeError("Wrong number of arguments"); - dynamic_cast(l).get_object().*ptr=st.args[0].get(); + if(st.args.size()!=1) throw TypeError(st.get_location()+": Wrong number of arguments"); + dynamic_cast(l).get_object().*ptr0=st.args[0].get(); } private: - PointerType ptr; + Pointer0Type ptr0; }; -class Loader + +template +class LoadValue2: public LoaderAction { public: - void load(const Statement &st) - { - for(std::list::const_iterator i=st.sub.begin(); i!=st.sub.end(); ++i) - load_statement(*i); - } - void load(Parser &p) - { - while(p) - { - Statement st=p.parse(); - if(st.valid) - load_statement(st); - } - } - virtual ~Loader() + typedef T0 L::*Pointer0Type; + typedef T1 L::*Pointer1Type; + + LoadValue2(Pointer0Type p0, Pointer1Type p1): ptr0(p0), ptr1(p1) { } + void execute(Loader &l, const Statement &st) const { - for(ActionMap::iterator i=actions.begin(); i!=actions.end(); ++i) - delete i->second; + if(st.args.size()!=2) throw TypeError(st.get_location()+": Wrong number of arguments"); + dynamic_cast(l).get_object().*ptr0=st.args[0].get(); + dynamic_cast(l).get_object().*ptr1=st.args[1].get(); } +private: + Pointer0Type ptr0; + Pointer1Type ptr1; +}; + + +/** +Base class for data loaders. To enable objects of a certain class to be loaded +from datafiles, create a public Loader class in it, derived from this class. +Typically the Loader class contains a reference to the object being loaded. If +you want to load data members of the object directly, the Loader class must +have a member function get_object() returning that reference. +*/ +class Loader +{ +public: + /** + Loads data from a statement. This is normally only used by the Loader class + itself for loading sub-items, but needs to be public so it can be accessed + in derived objects. + */ + void load(const Statement &st); + + /** + Loads statements from a parser. + */ + void load(Parser &p); + + virtual ~Loader(); protected: Loader(): cur_st(0) { } - + template void add(const std::string &k, void (L::*func)()) { actions.insert(typename ActionMap::value_type(k, new LoaderFunc0(func))); } - + template void add(const std::string &k, void (L::*func)(A0)) { actions.insert(typename ActionMap::value_type(k, new LoaderFunc1(func))); } - + template void add(const std::string &k, void (L::*func)(A0, A1)) { actions.insert(typename ActionMap::value_type(k, new LoaderFunc2(func))); } - + template void add(const std::string &k, void (L::*func)(A0, A1, A2)) { actions.insert(typename ActionMap::value_type(k, new LoaderFunc3(func))); } - + template void add(const std::string &k, void (L::*func)(A0, A1, A2, A3)) { actions.insert(typename ActionMap::value_type(k, new LoaderFunc4(func))); } - template - void add(const std::string &k, T L::*p) - { actions.insert(typename ActionMap::value_type(k, new LoadValue(p))); } + template + void add(const std::string &k, T0 L::*p0) + { actions.insert(typename ActionMap::value_type(k, new LoadValue1(p0))); } + + template + void add(const std::string &k, T0 L::*p0, T1 L::*p1) + { actions.insert(typename ActionMap::value_type(k, new LoadValue2(p0, p1))); } + void add(const std::string &k) + { actions.insert(ActionMap::value_type(k, 0)); } + + /** + Loads a sub-object from the statement being currently processed. The Loader + class of the sub-object is automatically used. + */ template void load_sub(S &s) - { load_sub(s); } + { load_sub(s); } - template + /** + Loads a sub-object with a custom Loader class. + */ + template void load_sub(S &s) { if(!cur_st) - throw Exception("load_sub called without current statement"); + throw InvalidState("load_sub called without current statement"); L loader(s); loader.load(*cur_st); } + + /** + Loads a sub-object with a custom Loader class that takes one argument in + addition to to object to be loaded. + */ + template + void load_sub(S &s, T &p) + { + if(!cur_st) + throw InvalidState("load_sub called without current statement"); + L loader(s, p); + loader.load(*cur_st); + } private: typedef std::map ActionMap; ActionMap actions; const Statement *cur_st; - void load_statement(const Statement &st) - { - cur_st=&st; - ActionMap::iterator j=actions.find(st.keyword); - if(j==actions.end()) - throw Exception(st.get_location()+": Unknown keyword '"+st.keyword+"'"); - j->second->execute(*this, st); - cur_st=0; - } + void load_statement(const Statement &st); }; -} // namespace Parser +/** +Loads an object from a file. The object must have a public Loader class. +*/ +template +void load(T &obj, const std::string &fn) +{ + std::ifstream in(fn.c_str()); + if(!in) + throw Exception("Couldn't open "+fn); + + Parser parser(in, fn); + typename T::Loader loader(obj); + loader.load(parser); +} + +} // namespace DataFile } // namespace Msp #endif