X-Git-Url: http://git.tdb.fi/?p=libs%2Fdatafile.git;a=blobdiff_plain;f=source%2Floader.h;h=fe928048508d208aafe339def238a4cdc722dc2d;hp=2a2d1416ece760be799037c022662c57244b9cc9;hb=1a3b30ea35fbc19e56bbd35e4ee1811d8d5e02a4;hpb=802f5b965a98ce0652ca0997c1c64f0bb2e76936 diff --git a/source/loader.h b/source/loader.h index 2a2d141..fe92804 100644 --- a/source/loader.h +++ b/source/loader.h @@ -1,260 +1,93 @@ -/* $Id$ - -This file is part of libmspdatafile -Copyright © 2006-2008 Mikko Rasa, Mikkosoft Productions -Distributed under the LGPL -*/ - #ifndef MSP_DATAFILE_LOADER_H_ #define MSP_DATAFILE_LOADER_H_ #include -#include #include -#include "except.h" +#include "loaderaction.h" #include "parser.h" #include "statement.h" -#include "value.h" namespace Msp { 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() { } -}; +Base class for data loaders. This class only provides core functionality. +You'll almost certainly want to use one of the BasicLoader classes instead. +Under normal circumstances, a class capable of being loaded should have a +nested typed called Loader which resolves to a descendant of this class. If +another structure is used, the loader object must be constructed manually. -/** -Loads a statement by calling a function that takes no arguments. -*/ -template -class LoaderFunc0: public LoaderAction -{ -public: - typedef void (L::*FuncType)(); +A loader class should execute one or more calls to the various add() functions +to register actions with expected keywords. Currently possible actions are +calling a function of the loader, storing values in member variables of an +object and ignoring the statement. If a unexpected keyword is encountered, an +exception is thrown and the loading is aborted. - LoaderFunc0(FuncType f): func(f) { } - void execute(Loader &l, const Statement &st) const - { - if(st.args.size()!=0) throw TypeError("Wrong number of arguments"); - (dynamic_cast(l).*func)(); - }; -private: - FuncType func; -}; +A sub-object can be loaded with one of the load_sub functions. +When loading has finished successfully, the virtual function finish() is +called. Any post-processing of the data should be placed here and not in the +destructor. -/** -Loads a statement by calling a function that takes one argument. +See also classes ObjectLoader and CollectionObjectLoader in objectloader.h. */ -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"); - (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"); - (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"); - (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get(), st.args[2].get()); - } -private: - FuncType func; -}; - - -template -class LoaderFunc4: public LoaderAction +class Loader { -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"); - (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get(), st.args[2].get(), st.args[3].get()); - } private: - FuncType func; -}; + typedef std::map ActionMap; + ActionMap actions; + Parser *cur_parser; + unsigned cur_level; + const Statement *cur_st; + bool sub_loaded; + bool direct; + std::list aux_loaders; +protected: + bool check_sub_loads; -template -class LoaderFunc5: public LoaderAction -{ + Loader(); public: - typedef void (L::*FuncType)(A0, A1, A2, A3, A4); - - LoaderFunc5(FuncType f): func(f) { } - void execute(Loader &l, const Statement &st) const - { - if(st.args.size()!=5) throw TypeError("Wrong number of arguments"); - (dynamic_cast(l).*func)(st.args[0].get(), st.args[1].get(), st.args[2].get(), st.args[3].get(), st.args[4].get()); - } -private: - FuncType func; -}; - + virtual ~Loader(); -template -class LoadValue1: public LoaderAction -{ -public: - typedef T0 L::*Pointer0Type; + /** Loads statements from a parser. */ + void load(Parser &p); - 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().*ptr0=st.args[0].get(); - } private: - Pointer0Type ptr0; -}; + /** Loads data from a statement. */ + void load(const Statement &st); + /** Loads statemsnts from a parser, feeding them directly to actions. */ + void load_direct(Parser &, unsigned); -template -class LoadValue1: public LoaderAction -{ -public: - typedef T0 *L::*Pointer0Type; + /** Processes a single statement */ + void load_statement(const Statement &st); - LoadValue1(Pointer0Type p0): ptr0(p0) { } - void execute(Loader &l, const Statement &st) const +protected: + /** Loads a sub-object from the statement being processed. The Loader class + of the sub-object is automatically used. */ + template + void load_sub(S &s) { - if(st.args.size()!=1) throw TypeError("Wrong number of arguments"); - typename L::Loader &ldr=dynamic_cast(l); - ldr.get_object().*ptr0=ldr.get_collection().template get(st.args[0].get()); + typename S::Loader ldr(s); + load_sub_with(ldr); } -private: - Pointer0Type ptr0; -}; - -template -class LoadValue2: public LoaderAction -{ -public: - 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 + /** Loads a sub-object from the statement being processed with an extra + parameter for the Loader. The Loader class of the sub-object is + automatically used. */ + template + void load_sub(S &s, T &p) { - if(st.args.size()!=2) throw TypeError("Wrong number of arguments"); - dynamic_cast(l).get_object().*ptr0=st.args[0].get(); - dynamic_cast(l).get_object().*ptr1=st.args[1].get(); + typename S::Loader ldr(s, p); + load_sub_with(ldr); } -private: - Pointer0Type ptr0; - Pointer1Type ptr1; -}; - -/** -Base class for data loaders. To give loading capabilities to a class, create a -public Loader class in it, derived from this class. Typically a loader object -contains a reference to the loaded object. To make use of loading directly -into data members, the Loader class must have a get_object() member function, -returning that reference. If direct loading of pointers is desired, the Loader -class must also have a get_collection() member function, returning a collection -to get pointers from. -*/ -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) { } + /** Processes the current statement's substatements with another Loader. */ + void load_sub_with(Loader &); - /** - Adds a keyword that is loaded with a zero-argument function. - */ + /** Adds a keyword that is loaded by calling a function. */ template void add(const std::string &k, void (L::*func)()) { add(k, new LoaderFunc0(func)); } @@ -279,9 +112,7 @@ protected: void add(const std::string &k, void (L::*func)(A0, A1, A2, A3, A4)) { add(k, new LoaderFunc5(func)); } - /** - Adds a keyword that is loaded into a variable of the loaded object. - */ + /** Adds a keyword that is loaded into a member of the loaded object. */ template void add(const std::string &k, T0 L::*p0) { add(k, new LoadValue1(p0)); } @@ -290,72 +121,43 @@ protected: void add(const std::string &k, T0 L::*p0, T1 L::*p1) { add(k, new LoadValue2(p0, p1)); } - /** - Adds a keyword that is recognized but ignored. - */ + /** Adds a keyword that is recognized but ignored. */ void add(const std::string &k) { add(k, 0); } - /** - Loads a sub-object from the statement being processed. The Loader class of - the sub-object is automatically used. - */ - template - void load_sub(S &s) - { - typename S::Loader ldr(s); - load_sub_with(ldr); - } - - /** - Loads a sub-object from the statement being processed with an extra parameter - for the Loader. The Loader class of the sub-object is automatically used. - */ - template - void load_sub(S &s, T &p) - { - typename S::Loader ldr(s, p); - load_sub_with(ldr); - } - - /** - Processes the current statement's substatements with another Loader. - */ - void load_sub_with(Loader &); +private: + void add(const std::string &, LoaderAction *); - /** - Returns the source of the statement being processed. This can be used to - implement relative paths in include-like statements. Note that the source - may not necessarily be a file. - */ - const std::string &get_source() const - { - if(!cur_st) - throw InvalidState("get_source called without current statement"); - return cur_st->source; - } +protected: + void add_auxiliary_loader(Loader &); - virtual void finish() { } private: - typedef std::map ActionMap; + bool has_action(const StatementKey &) const; + LoaderAction *find_action(const StatementKey &) const; - ActionMap actions; - const Statement *cur_st; +protected: + /** Returns the source of the statement being processed. This can be used + to implement relative paths in include-like statements. Note that the + source may not necessarily be a file. */ + const std::string &get_source() const; - void add(const std::string &, LoaderAction *); - void load_statement(const Statement &st); + /** Returns the keyword of the statement being processed. Can be used to + implement dynamic keywords. */ + const std::string &get_keyword() const; + + virtual void finish() { } }; + /** Loads an object from a file. The object must have a public Loader class. */ template void load(T &obj, const std::string &fn) { - IO::File in(fn); - IO::Buffered buf(in); + IO::BufferedFile in(fn); - Parser parser(buf, fn); + Parser parser(in, fn); typename T::Loader loader(obj); loader.load(parser); } @@ -363,10 +165,9 @@ void load(T &obj, const std::string &fn) template void load(T &obj, const std::string &fn, U &arg) { - IO::File in(fn); - IO::Buffered buf(in); + IO::BufferedFile in(fn); - Parser parser(buf, fn); + Parser parser(in, fn); typename T::Loader loader(obj, arg); loader.load(parser); }