2012-05-16 11:54:46 -06:00

1040 lines
30 KiB
C++

// This file is distributed under the BSD License.
// See "license.txt" for details.
// Copyright 2009-2012, Jonathan Turner (jonathan@emptycrate.com)
// and Jason Turner (jason@emptycrate.com)
// http://www.chaiscript.com
#ifndef CHAISCRIPT_DISPATCHKIT_HPP_
#define CHAISCRIPT_DISPATCHKIT_HPP_
#include <typeinfo>
#include <string>
#include <map>
#include <set>
#include <stdexcept>
#include <vector>
#include <iostream>
#include <deque>
#include <algorithm>
#include "boxed_value.hpp"
#include "type_info.hpp"
#include "proxy_functions.hpp"
#include "proxy_constructors.hpp"
#include "dynamic_object.hpp"
#include "../chaiscript_threading.hpp"
/// \namespace chaiscript::dispatch
/// \brief Classes and functions specific to the runtime dispatch side of ChaiScript. Some items may be of use to the end user.
namespace chaiscript
{
namespace exception
{
/**
* Exception thrown in the case that an object name is invalid because it is a reserved word
*/
class reserved_word_error : public std::runtime_error
{
public:
reserved_word_error(const std::string &t_word) noexcept
: std::runtime_error("Reserved word not allowed in object name: " + t_word), m_word(t_word)
{
}
virtual ~reserved_word_error() noexcept {}
std::string word() const
{
return m_word;
}
private:
std::string m_word;
};
/**
* Exception thrown in the case that an object name is invalid because it already exists in current context
*/
class name_conflict_error : public std::runtime_error
{
public:
name_conflict_error(const std::string &t_name) throw()
: std::runtime_error("Name already exists in current context " + t_name), m_name(t_name)
{
}
virtual ~name_conflict_error() throw() {}
std::string name() const
{
return m_name;
}
private:
std::string m_name;
};
/**
* Exception thrown in the case that a non-const object was added as a shared object
*/
class global_non_const : public std::runtime_error
{
public:
global_non_const() noexcept
: std::runtime_error("a global object must be const")
{
}
virtual ~global_non_const() noexcept {}
};
}
/// \brief Holds a collection of ChaiScript settings which can be applied to the ChaiScript runtime.
/// Used to implement loadable module support.
class Module
{
public:
Module &add(const Type_Info &ti, const std::string &name)
{
m_typeinfos.push_back(std::make_pair(ti, name));
return *this;
}
Module &add(const Dynamic_Cast_Conversion &d)
{
m_conversions.push_back(d);
return *this;
}
Module &add(const Proxy_Function &f, const std::string &name)
{
m_funcs.push_back(std::make_pair(f, name));
return *this;
}
Module &add_global_const(const Boxed_Value &t_bv, const std::string &t_name)
{
if (!t_bv.is_const())
{
throw chaiscript::exception::global_non_const();
}
m_globals.push_back(std::make_pair(t_bv, t_name));
return *this;
}
//Add a bit of chaiscript to eval during module implementation
Module &eval(const std::string &str)
{
m_evals.push_back(str);
return *this;
}
Module &add(const std::shared_ptr<Module> &m)
{
m->apply(*this, *this);
return *m;
}
template<typename Eval, typename Engine>
void apply(Eval &t_eval, Engine &t_engine) const
{
apply(m_typeinfos.begin(), m_typeinfos.end(), t_engine);
apply(m_funcs.begin(), m_funcs.end(), t_engine);
apply_eval(m_evals.begin(), m_evals.end(), t_eval);
apply_single(m_conversions.begin(), m_conversions.end(), t_engine);
apply_globals(m_globals.begin(), m_globals.end(), t_engine);
}
private:
std::vector<std::pair<Type_Info, std::string> > m_typeinfos;
std::vector<std::pair<Proxy_Function, std::string> > m_funcs;
std::vector<std::pair<Boxed_Value, std::string> > m_globals;
std::vector<std::string> m_evals;
std::vector<Dynamic_Cast_Conversion> m_conversions;
template<typename T, typename InItr>
void apply(InItr begin, InItr end, T &t) const
{
while (begin != end)
{
try {
t.add(begin->first, begin->second);
} catch (const chaiscript::exception::name_conflict_error &) {
/// \todo Should we throw an error if there's a name conflict
/// while applying a module?
}
++begin;
}
}
template<typename T, typename InItr>
void apply_globals(InItr begin, InItr end, T &t) const
{
while (begin != end)
{
t.add_global_const(begin->first, begin->second);
++begin;
}
}
template<typename T, typename InItr>
void apply_single(InItr begin, InItr end, T &t) const
{
while (begin != end)
{
t.add(*begin);
++begin;
}
}
template<typename T, typename InItr>
void apply_eval(InItr begin, InItr end, T &t) const
{
while (begin != end)
{
t.eval(*begin);
++begin;
}
}
};
/// Convenience typedef for Module objects to be added to the ChaiScript runtime
typedef std::shared_ptr<Module> ModulePtr;
namespace detail
{
/**
* A Proxy_Function implementation that is able to take
* a vector of Proxy_Functions and perform a dispatch on them. It is
* used specifically in the case of dealing with Function object variables
*/
class Dispatch_Function : public dispatch::Proxy_Function_Base
{
public:
Dispatch_Function(const std::vector<Proxy_Function> &t_funcs)
: Proxy_Function_Base(build_type_infos(t_funcs)),
m_funcs(t_funcs)
{
}
virtual bool operator==(const dispatch::Proxy_Function_Base &rhs) const
{
try {
const Dispatch_Function &dispatchfun = dynamic_cast<const Dispatch_Function &>(rhs);
return m_funcs == dispatchfun.m_funcs;
} catch (const std::bad_cast &) {
return false;
}
}
virtual ~Dispatch_Function() {}
virtual std::vector<Const_Proxy_Function> get_contained_functions() const
{
return std::vector<Const_Proxy_Function>(m_funcs.begin(), m_funcs.end());
}
virtual int get_arity() const
{
typedef std::vector<Proxy_Function> function_vec;
function_vec::const_iterator begin = m_funcs.begin();
const function_vec::const_iterator end = m_funcs.end();
if (begin != end)
{
int arity = (*begin)->get_arity();
++begin;
while (begin != end)
{
if (arity != (*begin)->get_arity())
{
// The arities in the list do not match, so it's unspecified
return -1;
}
++begin;
}
return arity;
}
return -1; // unknown arity
}
virtual bool call_match(const std::vector<Boxed_Value> &vals) const
{
typedef std::vector<Proxy_Function> function_vec;
function_vec::const_iterator begin = m_funcs.begin();
function_vec::const_iterator end = m_funcs.end();
while (begin != end)
{
if ((*begin)->call_match(vals))
{
return true;
} else {
++begin;
}
}
return false;
}
virtual std::string annotation() const
{
return "Multiple method dispatch function wrapper.";
}
protected:
virtual Boxed_Value do_call(const std::vector<Boxed_Value> &params) const
{
return dispatch::dispatch(m_funcs.begin(), m_funcs.end(), params);
}
private:
std::vector<Proxy_Function> m_funcs;
static std::vector<Type_Info> build_type_infos(const std::vector<Proxy_Function> &t_funcs)
{
typedef std::vector<Proxy_Function> function_vec;
function_vec::const_iterator begin = t_funcs.begin();
const function_vec::const_iterator end = t_funcs.end();
if (begin != end)
{
std::vector<Type_Info> type_infos = (*begin)->get_param_types();
++begin;
bool sizemismatch = false;
while (begin != end)
{
std::vector<Type_Info> param_types = (*begin)->get_param_types();
if (param_types.size() != type_infos.size())
{
sizemismatch = true;
}
for (size_t i = 0; i < type_infos.size() && i < param_types.size(); ++i)
{
if (!(type_infos[i] == param_types[i]))
{
type_infos[i] = detail::Get_Type_Info<Boxed_Value>::get();
}
}
++begin;
}
assert(type_infos.size() > 0 && " type_info vector size is < 0, this is only possible if something else is broken");
if (sizemismatch)
{
type_infos.resize(1);
}
return type_infos;
}
return std::vector<Type_Info>();
}
};
}
namespace detail
{
/**
* Main class for the dispatchkit. Handles management
* of the object stack, functions and registered types.
*/
class Dispatch_Engine
{
public:
typedef std::map<std::string, chaiscript::Type_Info> Type_Name_Map;
typedef std::map<std::string, Boxed_Value> Scope;
typedef std::deque<Scope> StackData;
typedef std::shared_ptr<StackData> Stack;
struct State
{
std::map<std::string, std::vector<Proxy_Function> > m_functions;
std::map<std::string, Boxed_Value> m_global_objects;
Type_Name_Map m_types;
std::set<std::string> m_reserved_words;
State &operator=(const State &) = default;
};
Dispatch_Engine()
: m_place_holder(std::shared_ptr<dispatch::Placeholder_Object>(new dispatch::Placeholder_Object()))
{
}
~Dispatch_Engine()
{
detail::Dynamic_Conversions::get().cleanup(m_conversions.begin(), m_conversions.end());
}
/**
* Add a new conversion for upcasting to a base class
*/
void add(const Dynamic_Cast_Conversion &d)
{
m_conversions.push_back(d);
return detail::Dynamic_Conversions::get().add_conversion(d);
}
/**
* Add a new named Proxy_Function to the system
*/
void add(const Proxy_Function &f, const std::string &name)
{
validate_object_name(name);
add_function(f, name);
}
/**
* Set the value of an object, by name. If the object
* is not available in the current scope it is created
*/
/*
void add(const Boxed_Value &obj, const std::string &name)
{
validate_object_name(name);
StackData &stack = get_stack_data();
for (int i = static_cast<int>(stack.size())-1; i >= 0; --i)
{
std::map<std::string, Boxed_Value>::const_iterator itr = stack[i].find(name);
if (itr != stack[i].end())
{
stack[i][name] = obj;
return;
}
}
add_object(name, obj);
}
*/
/**
* Adds a named object to the current scope
*/
void add_object(const std::string &name, const Boxed_Value &obj)
{
StackData &stack = get_stack_data();
validate_object_name(name);
Scope &scope = stack.back();
Scope::iterator itr = scope.find(name);
if (itr != stack.back().end())
{
throw chaiscript::exception::name_conflict_error(name);
} else {
stack.back().insert(std::make_pair(name, obj));
}
}
/**
* Adds a new global shared object, between all the threads
*/
void add_global_const(const Boxed_Value &obj, const std::string &name)
{
validate_object_name(name);
if (!obj.is_const())
{
throw chaiscript::exception::global_non_const();
}
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l(m_global_object_mutex);
if (m_state.m_global_objects.find(name) != m_state.m_global_objects.end())
{
throw chaiscript::exception::name_conflict_error(name);
} else {
m_state.m_global_objects.insert(std::make_pair(name, obj));
}
}
/**
* Adds a new scope to the stack
*/
void new_scope()
{
StackData &stack = get_stack_data();
stack.push_back(Scope());
}
/**
* Pops the current scope from the stack
*/
void pop_scope()
{
StackData &stack = get_stack_data();
if (stack.size() > 1)
{
stack.pop_back();
} else {
throw std::range_error("Unable to pop global stack");
}
}
/**
* Swaps out the stack with a new stack
* \returns the old stack
* \param[in] s The new stack
*/
Stack set_stack(const Stack &s)
{
Stack old = m_stack_holder->stack;
m_stack_holder->stack = s;
return old;
}
Stack new_stack() const
{
Stack s(new Stack::element_type());
s->push_back(Scope());
return s;
}
Stack get_stack() const
{
return m_stack_holder->stack;
}
/**
* Searches the current stack for an object of the given name
* includes a special overload for the _ place holder object to
* ensure that it is always in scope.
*/
Boxed_Value get_object(const std::string &name) const
{
// Is it a placeholder object?
if (name == "_")
{
return m_place_holder;
}
StackData &stack = get_stack_data();
// Is it in the stack?
for (int i = static_cast<int>(stack.size())-1; i >= 0; --i)
{
std::map<std::string, Boxed_Value>::const_iterator stackitr = stack[i].find(name);
if (stackitr != stack[i].end())
{
return stackitr->second;
}
}
// Is the value we are looking for a global?
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_global_object_mutex);
std::map<std::string, Boxed_Value>::const_iterator itr = m_state.m_global_objects.find(name);
if (itr != m_state.m_global_objects.end())
{
return itr->second;
}
}
// If all that failed, then check to see if it's a function
std::vector<Proxy_Function> funcs = get_function(name);
if (funcs.empty())
{
throw std::range_error("Object not known: " + name);
} else {
if (funcs.size() == 1)
{
// Return the first item if there is only one,
// no reason to take the cast of the extra level of dispatch
return const_var(*funcs.begin());
} else {
return Boxed_Value(Const_Proxy_Function(new Dispatch_Function(funcs)));
}
}
}
/**
* Registers a new named type
*/
void add(const Type_Info &ti, const std::string &name)
{
add_global_const(const_var(ti), name + "_type");
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
m_state.m_types.insert(std::make_pair(name, ti));
}
/**
* Returns the type info for a named type
*/
Type_Info get_type(const std::string &name) const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
Type_Name_Map::const_iterator itr = m_state.m_types.find(name);
if (itr != m_state.m_types.end())
{
return itr->second;
}
throw std::range_error("Type Not Known");
}
/**
* Returns the registered name of a known type_info object
* compares the "bare_type_info" for the broadest possible
* match
*/
std::string get_type_name(const Type_Info &ti) const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
for (Type_Name_Map::const_iterator itr = m_state.m_types.begin();
itr != m_state.m_types.end();
++itr)
{
if (itr->second.bare_equal(ti))
{
return itr->first;
}
}
return ti.bare_name();
}
/**
* Return all registered types
*/
std::vector<std::pair<std::string, Type_Info> > get_types() const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
return std::vector<std::pair<std::string, Type_Info> >(m_state.m_types.begin(), m_state.m_types.end());
}
/**
* Return a function by name
*/
std::vector< Proxy_Function >
get_function(const std::string &t_name) const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
const std::map<std::string, std::vector<Proxy_Function> > &funs = get_functions_int();
std::map<std::string, std::vector<Proxy_Function> >::const_iterator itr
= funs.find(t_name);
if (itr != funs.end())
{
return itr->second;
} else {
return std::vector<Proxy_Function>();
}
}
/**
* Return true if a function exists
*/
bool function_exists(const std::string &name) const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
const std::map<std::string, std::vector<Proxy_Function> > &functions = get_functions_int();
return functions.find(name) != functions.end();
}
/**
* Get a vector of all registered functions
*/
std::vector<std::pair<std::string, Proxy_Function > > get_functions() const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
std::vector<std::pair<std::string, Proxy_Function> > rets;
const std::map<std::string, std::vector<Proxy_Function> > &functions = get_functions_int();
for (std::map<std::string, std::vector<Proxy_Function> >::const_iterator itr = functions.begin();
itr != functions.end();
++itr)
{
for (std::vector<Proxy_Function>::const_iterator itr2 = itr->second.begin();
itr2 != itr->second.end();
++itr2)
{
rets.push_back(std::make_pair(itr->first, *itr2));
}
}
return rets;
}
void add_reserved_word(const std::string &name)
{
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
m_state.m_reserved_words.insert(name);
}
Boxed_Value call_function(const std::string &t_name, const std::vector<Boxed_Value> &params) const
{
std::vector<Proxy_Function> functions = get_function(t_name);
return dispatch::dispatch(functions.begin(), functions.end(), params);
}
Boxed_Value call_function(const std::string &t_name) const
{
return call_function(t_name, std::vector<Boxed_Value>());
}
Boxed_Value call_function(const std::string &t_name, const Boxed_Value &p1) const
{
std::vector<Boxed_Value> params;
params.push_back(p1);
return call_function(t_name, params);
}
Boxed_Value call_function(const std::string &t_name, const Boxed_Value &p1, const Boxed_Value &p2) const
{
std::vector<Boxed_Value> params;
params.push_back(p1);
params.push_back(p2);
return call_function(t_name, params);
}
/**
* Dump object info to stdout
*/
void dump_object(const Boxed_Value &o) const
{
std::cout << (o.is_const()?"const ":"") << type_name(o) << std::endl;
}
/**
* Dump type info to stdout
*/
void dump_type(const Type_Info &type) const
{
std::cout << (type.is_const()?"const ":"") << get_type_name(type);
}
/**
* Dump function to stdout
*/
void dump_function(const std::pair<const std::string, Proxy_Function > &f) const
{
std::vector<Type_Info> params = f.second->get_param_types();
std::string annotation = f.second->annotation();
if (annotation.size() > 0) {
std::cout << annotation;
}
dump_type(params.front());
std::cout << " " << f.first << "(";
for (std::vector<Type_Info>::const_iterator itr = params.begin() + 1;
itr != params.end();
)
{
dump_type(*itr);
++itr;
if (itr != params.end())
{
std::cout << ", ";
}
}
std::cout << ") " << std::endl;
}
/**
* Dump all system info to stdout
*/
void dump_system() const
{
std::cout << "Registered Types: " << std::endl;
std::vector<std::pair<std::string, Type_Info> > types = get_types();
for (std::vector<std::pair<std::string, Type_Info> >::const_iterator itr = types.begin();
itr != types.end();
++itr)
{
std::cout << itr->first << ": ";
std::cout << itr->second.bare_name();
std::cout << std::endl;
}
std::cout << std::endl;
std::vector<std::pair<std::string, Proxy_Function > > funcs = get_functions();
std::cout << "Functions: " << std::endl;
for (std::vector<std::pair<std::string, Proxy_Function > >::const_iterator itr = funcs.begin();
itr != funcs.end();
++itr)
{
dump_function(*itr);
}
std::cout << std::endl;
}
/**
* return true if the Boxed_Value matches the registered type by name
*/
bool is_type(const Boxed_Value &r, const std::string &user_typename) const
{
try {
if (get_type(user_typename).bare_equal(r.get_type_info()))
{
return true;
}
} catch (const std::range_error &) {
}
try {
const dispatch::Dynamic_Object &d = boxed_cast<const dispatch::Dynamic_Object &>(r);
return d.get_type_name() == user_typename;
} catch (const std::bad_cast &) {
}
return false;
}
std::string type_name(const Boxed_Value &obj) const
{
return get_type_name(obj.get_type_info());
}
State get_state()
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l2(m_global_object_mutex);
return m_state;
}
void set_state(const State &t_state)
{
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l2(m_global_object_mutex);
m_state = t_state;
}
private:
/**
* Returns the current stack
* make const/non const versions
*/
StackData &get_stack_data() const
{
return *(m_stack_holder->stack);
}
const std::map<std::string, std::vector<Proxy_Function> > &get_functions_int() const
{
return m_state.m_functions;
}
std::map<std::string, std::vector<Proxy_Function> > &get_functions_int()
{
return m_state.m_functions;
}
static bool function_less_than(const Proxy_Function &lhs, const Proxy_Function &rhs)
{
const std::vector<Type_Info> lhsparamtypes = lhs->get_param_types();
const std::vector<Type_Info> rhsparamtypes = rhs->get_param_types();
const size_t lhssize = lhsparamtypes.size();
const size_t rhssize = rhsparamtypes.size();
const Type_Info boxed_type = user_type<Boxed_Value>();
const Type_Info boxed_pod_type = user_type<Boxed_Number>();
std::shared_ptr<const dispatch::Dynamic_Proxy_Function> dynamic_lhs(std::dynamic_pointer_cast<const dispatch::Dynamic_Proxy_Function>(lhs));
std::shared_ptr<const dispatch::Dynamic_Proxy_Function> dynamic_rhs(std::dynamic_pointer_cast<const dispatch::Dynamic_Proxy_Function>(rhs));
if (dynamic_lhs && dynamic_rhs)
{
if (dynamic_lhs->get_guard())
{
if (dynamic_rhs->get_guard())
{
return false;
} else {
return true;
}
} else {
return false;
}
}
if (dynamic_lhs && !dynamic_rhs)
{
return false;
}
if (!dynamic_lhs && dynamic_rhs)
{
return true;
}
for (size_t i = 1; i < lhssize && i < rhssize; ++i)
{
const Type_Info lt = lhsparamtypes[i];
const Type_Info rt = rhsparamtypes[i];
if (lt.bare_equal(rt) && lt.is_const() == rt.is_const())
{
continue; // The first two types are essentially the same, next iteration
}
// const is after non-const for the same type
if (lt.bare_equal(rt) && lt.is_const() && !rt.is_const())
{
return false;
}
if (lt.bare_equal(rt) && !lt.is_const())
{
return true;
}
// boxed_values are sorted last
if (lt.bare_equal(boxed_type))
{
return false;
}
if (rt.bare_equal(boxed_type))
{
if (lt.bare_equal(boxed_pod_type))
{
return true;
}
return true;
}
if (lt.bare_equal(boxed_pod_type))
{
return false;
}
if (rt.bare_equal(boxed_pod_type))
{
return true;
}
// otherwise, we want to sort by typeid
return lt < rt;
}
return false;
}
/**
* Throw a reserved_word exception if the name is not allowed
*/
void validate_object_name(const std::string &name) const
{
chaiscript::detail::threading::shared_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
if (m_state.m_reserved_words.find(name) != m_state.m_reserved_words.end())
{
throw chaiscript::exception::reserved_word_error(name);
}
}
/**
* Implementation detail for adding a function.
* \throws exception::name_conflict_error if there's a function matching the given one being added
*/
void add_function(const Proxy_Function &t_f, const std::string &t_name)
{
chaiscript::detail::threading::unique_lock<chaiscript::detail::threading::shared_mutex> l(m_mutex);
std::map<std::string, std::vector<Proxy_Function> > &funcs = get_functions_int();
std::map<std::string, std::vector<Proxy_Function> >::iterator itr
= funcs.find(t_name);
if (itr != funcs.end())
{
std::vector<Proxy_Function> &vec = itr->second;
for (std::vector<Proxy_Function>::const_iterator itr2 = vec.begin();
itr2 != vec.end();
++itr2)
{
if ((*t_f) == *(*itr2))
{
throw chaiscript::exception::name_conflict_error(t_name);
}
}
vec.push_back(t_f);
std::stable_sort(vec.begin(), vec.end(), &function_less_than);
} else {
std::vector<Proxy_Function> vec;
vec.push_back(t_f);
funcs.insert(std::make_pair(t_name, vec));
}
}
mutable chaiscript::detail::threading::shared_mutex m_mutex;
mutable chaiscript::detail::threading::shared_mutex m_global_object_mutex;
struct Stack_Holder
{
Stack_Holder()
: stack(new StackData())
{
stack->push_back(Scope());
}
Stack stack;
};
std::vector<Dynamic_Cast_Conversion> m_conversions;
chaiscript::detail::threading::Thread_Storage<Stack_Holder> m_stack_holder;
State m_state;
Boxed_Value m_place_holder;
};
}
}
#endif