-/*
-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_
-#include <fstream>
+#ifndef MSP_DATAFILE_LOADER_H_
+#define MSP_DATAFILE_LOADER_H_
+
#include <map>
-#include "error.h"
+#include <msp/io/buffered.h>
+#include <msp/io/file.h>
+#include "except.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<typename L>
class LoaderFunc0: public LoaderAction
{
public:
typedef void (L::*FuncType)();
-
+
LoaderFunc0(FuncType f): func(f) { }
void execute(Loader &l, const Statement &st) const
{
FuncType func;
};
+
+/**
+Loads a statement by calling a function that takes one argument.
+*/
template<typename L, typename A0>
class LoaderFunc1: public LoaderAction
{
public:
typedef void (L::*FuncType)(A0);
-
+
LoaderFunc1(FuncType f): func(f) { }
void execute(Loader &l, const Statement &st) const
{
FuncType func;
};
+
+/**
+Loads a statement by calling a function that takes an array of values.
+*/
+template<typename L, typename A0>
+class LoaderFunc1<L, const std::vector<A0> &>: public LoaderAction
+{
+public:
+ typedef void (L::*FuncType)(const std::vector<A0> &);
+
+ LoaderFunc1(FuncType f): func(f) { }
+ void execute(Loader &l, const Statement &st) const
+ {
+ std::vector<A0> values;
+ values.reserve(st.args.size());
+ for(ValueArray::const_iterator i=st.args.begin(); i!=st.args.end(); ++i)
+ values.push_back(i->get<A0>());
+ (dynamic_cast<L &>(l).*func)(values);
+ }
+private:
+ FuncType func;
+};
+
+
template<typename L, typename A0, typename A1>
class LoaderFunc2: public LoaderAction
{
public:
typedef void (L::*FuncType)(A0, A1);
-
+
LoaderFunc2(FuncType f): func(f) { }
void execute(Loader &l, const Statement &st) const
{
FuncType func;
};
+
template<typename L, typename A0, typename A1, typename A2>
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
{
FuncType func;
};
+
template<typename L, typename A0, typename A1, typename A2, typename A3>
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
{
FuncType func;
};
-template<typename L, typename T>
-class LoadValue: public LoaderAction
+
+template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+class LoaderFunc5: public LoaderAction
{
public:
- typedef T L::*PointerType;
-
- LoadValue(PointerType p): ptr(p) { }
+ 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()!=1) throw TypeError(st.get_location()+": Wrong number of arguments");
- dynamic_cast<typename L::Loader &>(l).get_object().*ptr=st.args[0].get<T>();
+ if(st.args.size()!=5) throw TypeError(st.get_location()+": Wrong number of arguments");
+ (dynamic_cast<L &>(l).*func)(st.args[0].get<A0>(), st.args[1].get<A1>(), st.args[2].get<A2>(), st.args[3].get<A3>(), st.args[4].get<A4>());
}
private:
- PointerType ptr;
+ FuncType func;
};
-class Loader
+
+template<typename L, typename T0>
+class LoadValue1: public LoaderAction
{
public:
- void load(const Statement &st)
+ typedef T0 L::*Pointer0Type;
+
+ LoadValue1(Pointer0Type p0): ptr0(p0) { }
+ void execute(Loader &l, const Statement &st) const
{
- for(std::list<Statement>::const_iterator i=st.sub.begin(); i!=st.sub.end(); ++i)
- load_statement(*i);
+ if(st.args.size()!=1) throw TypeError(st.get_location()+": Wrong number of arguments");
+ dynamic_cast<typename L::Loader &>(l).get_object().*ptr0=st.args[0].get<T0>();
}
- void load(Parser &p)
+private:
+ Pointer0Type ptr0;
+};
+
+
+template<typename L, typename T0>
+class LoadValue1<L, T0 *>: public LoaderAction
+{
+public:
+ typedef T0 *L::*Pointer0Type;
+
+ LoadValue1(Pointer0Type p0): ptr0(p0) { }
+ void execute(Loader &l, const Statement &st) const
{
- while(p)
- {
- Statement st=p.parse();
- if(st.valid)
- load_statement(st);
- }
+ if(st.args.size()!=1) throw TypeError(st.get_location()+": Wrong number of arguments");
+ typename L::Loader &ldr=dynamic_cast<typename L::Loader &>(l);
+ ldr.get_object().*ptr0=ldr.get_collection().template get<T0>(st.args[0].get<std::string>());
}
- virtual ~Loader()
+private:
+ Pointer0Type ptr0;
+};
+
+
+template<typename L, typename T0, typename T1>
+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
{
- 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<typename L::Loader &>(l).get_object().*ptr0=st.args[0].get<T0>();
+ dynamic_cast<typename L::Loader &>(l).get_object().*ptr1=st.args[1].get<T1>();
}
+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) { }
-
+
+ /**
+ Adds a keyword that is loaded with a zero-argument function.
+ */
template<typename L>
void add(const std::string &k, void (L::*func)())
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc0<L>(func))); }
-
+ { add(k, new LoaderFunc0<L>(func)); }
+
template<typename L, typename A0>
void add(const std::string &k, void (L::*func)(A0))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc1<L, A0>(func))); }
-
+ { add(k, new LoaderFunc1<L, A0>(func)); }
+
template<typename L, typename A0, typename A1>
void add(const std::string &k, void (L::*func)(A0, A1))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc2<L, A0, A1>(func))); }
-
+ { add(k, new LoaderFunc2<L, A0, A1>(func)); }
+
template<typename L, typename A0, typename A1, typename A2>
void add(const std::string &k, void (L::*func)(A0, A1, A2))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc3<L, A0, A1, A2>(func))); }
-
+ { add(k, new LoaderFunc3<L, A0, A1, A2>(func)); }
+
template<typename L, typename A0, typename A1, typename A2, typename A3>
void add(const std::string &k, void (L::*func)(A0, A1, A2, A3))
- { actions.insert(typename ActionMap::value_type(k, new LoaderFunc4<L, A0, A1, A2, A3>(func))); }
+ { add(k, new LoaderFunc4<L, A0, A1, A2, A3>(func)); }
+
+ template<typename L, typename A0, typename A1, typename A2, typename A3, typename A4>
+ void add(const std::string &k, void (L::*func)(A0, A1, A2, A3, A4))
+ { add(k, new LoaderFunc5<L, A0, A1, A2, A3, A4>(func)); }
- template<typename L, typename T>
- void add(const std::string &k, T L::*p)
- { actions.insert(typename ActionMap::value_type(k, new LoadValue<L, T>(p))); }
+ /**
+ Adds a keyword that is loaded into a variable of the loaded object.
+ */
+ template<typename L, typename T0>
+ void add(const std::string &k, T0 L::*p0)
+ { add(k, new LoadValue1<L, T0>(p0)); }
+ template<typename L, typename T0, typename T1>
+ void add(const std::string &k, T0 L::*p0, T1 L::*p1)
+ { add(k, new LoadValue2<L, T0, T1>(p0, p1)); }
+
+ /**
+ Adds a keyword that is recognized but ignored.
+ */
void add(const std::string &k)
- { actions.insert(ActionMap::value_type(k, 0)); }
+ { add(k, 0); }
+ /**
+ Loads a sub-object from the statement being processed. The Loader class of
+ the sub-object is automatically used.
+ */
template<typename S>
void load_sub(S &s)
- { load_sub<S, typename S::Loader>(s); }
+ {
+ typename S::Loader ldr(s);
+ load_sub_with(ldr);
+ }
- template<typename S, typename L>
- void load_sub(S &s)
+ /**
+ 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<typename S, typename T>
+ 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 &);
+
+ /**
+ 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 Exception("load_sub called without current statement");
- L loader(s);
- loader.load(*cur_st);
+ throw InvalidState("get_source called without current statement");
+ return cur_st->source;
}
+
+ virtual void finish() { }
private:
typedef std::map<std::string, LoaderAction *> 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+"'");
- if(j->second)
- j->second->execute(*this, st);
- cur_st=0;
- }
+ void add(const std::string &, LoaderAction *);
+ void load_statement(const Statement &st);
};
+/**
+Loads an object from a file. The object must have a public Loader class.
+*/
template<typename T>
void load(T &obj, const std::string &fn)
{
- std::ifstream in(fn.c_str());
- if(!in)
- throw Exception("Couldn't open "+fn);
+ IO::File in(fn);
+ IO::Buffered buf(in);
- Parser parser(in, fn);
+ Parser parser(buf, fn);
typename T::Loader loader(obj);
loader.load(parser);
}
-} // namespace Parser
+template<typename T, typename U>
+void load(T &obj, const std::string &fn, U &arg)
+{
+ IO::File in(fn);
+ IO::Buffered buf(in);
+
+ Parser parser(in, fn);
+ typename T::Loader loader(obj, arg);
+ loader.load(parser);
+}
+
+} // namespace DataFile
} // namespace Msp
#endif