dfhack/plugins/Dfusion/src/luaxx.cc

825 lines
25 KiB
C++

/* vim: set et sw=3 tw=0 fo=croqlaw cino=t0:
*
* Luaxx, the C++ Lua wrapper library.
* Copyright (c) 2006-2008 Matthew Nicholson
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
#include <luaxx.hpp>
#include <iostream>
#define LOG std::cout
/** @file
* Luaxx implementation file.
*/
namespace lua
{
void StackDump(lua_State *L)
{
int i;
int top = lua_gettop(L);
for (i = 1; i <= top; i++) /* repeat for each level */
{
int t = lua_type(L, i);
LOG<<i<<":";
switch (t)
{
case LUA_TSTRING: /* strings */
LOG<<"str ="<<lua_tostring(L, i)<<"\n";
break;
case LUA_TBOOLEAN: /* booleans */
LOG<<"bool="<<(lua_toboolean(L, i) ? "true" : "false")<<"\n";
break;
case LUA_TNUMBER: /* numbers */
LOG<<"num ="<<lua_tonumber(L, i)<<"\n";
break;
case LUA_TTABLE:
LOG<<lua_typename(L, t);
{
//LOG<<"PRE TOP:"<< lua_gettop(L)<<"\n";
lua_getglobal(L,"PrintTable");
//lua_insert(L,-2);
lua_pushvalue(L,i);
lua_pcall(L,1,0,0);
//LOG<<"POST TOP:"<< lua_gettop(L)<<"\n";
}
break;
default: /* other values */
LOG<<lua_typename(L, t);
{
//LOG<<"PRE TOP:"<< lua_gettop(L)<<"\n";
lua_getglobal(L,"tostring");
//lua_insert(L,-2);
lua_pushvalue(L,i);
lua_pcall(L,1,1,0);
LOG<<"=";
LOG<<lua_tostring(L,-1)<<"\n";
lua_pop(L,1);
//LOG<<"POST TOP:"<< lua_gettop(L)<<"\n";
}
break;
}
}
LOG<<"\n"; /* end the listing */
LOG<<"==============================\n";
}
#undef LOG
/// Construct our lua environment.
state::state() : L(luaL_newstate()), managed(true) {
if (L == NULL)
throw bad_alloc("Error creating lua state");
}
/** Construct our lua environment from an existing lua_State.
* @param L the existing state to use.
*
* This function differs from the normal constructor as it sets a flag
* that prevents lua_close() from being called when this class is
* destroyed.
*/
state::state(lua_State* L) :
L(L), managed(false) {
}
state& state::operator = (const state& t)
{
if(managed)
lua_close(L);
managed=false;
L=t.L;
return *this;
}
/// Destroy our lua environment.
state::~state() {
if (managed)
lua_close(L);
}
/** Push a nil onto the stack.
* @returns a reference to this lua::state
*/
state& state::push() {
lua_pushnil(L);
return *this;
}
/** Push a nil onto the stack.
* @returns a reference to this lua::state
*/
state& state::push(nil) {
lua_pushnil(L);
return *this;
}
/** Push a boolean onto the stack.
* @param boolean the value to push
* @returns a reference to this lua::state
*/
state& state::push(bool boolean) {
lua_pushboolean(L, boolean);
return *this;
}
/** Push a C-style string onto the stack.
* @param s the string to push
* @param length the length of the string
* @returns a reference to this lua::state
*/
state& state::push(const char* s, size_t length) {
lua_pushlstring(L, s, length);
return *this;
}
/** Push a C-style string onto the stack.
* @param s the string to push
* @note This must be a '0' terminated string.
* @returns a reference to this lua::state
*/
state& state::push(const char* s) {
lua_pushstring(L, s);
return *this;
}
/** Push an std::string onto the stack.
* @param s the string to push
* @returns a reference to this lua::state
*/
state& state::push(const std::string& s) {
lua_pushlstring(L, s.c_str(), s.size());
return *this;
}
/** Push an C function onto the stack.
* @param f the function to push
* @returns a reference to this lua::state
*/
state& state::push(cfunction f) {
lua_pushcfunction(L, f);
return *this;
}
/** Create a new table on to the stack.
* @see state::newtable()
* @returns a reference to this lua::state
*/
state& state::push(table) {
lua_newtable(L);
return *this;
}
/** Push a light userdatum on to the stack.
* @param p the pointer to push
* @returns a reference to this lua::state
*/
state& state::push(void* p) {
lua_pushlightuserdata(L, p);
return *this;
}
/** Get the value at index as a string.
* @param default_value this value is returned if the conversion fails
* @param index the index to get
* @note This function does \em not pop the value from the stack.
*
* @note lua::state::as(std::string()) will convert the value at the
* indicated index to a string <em>on the stack</em>. This can
* confuse lua::state::next();
*
* @returns the indicated value from the stack or the default value if the
* conversion fails
*/
template<>
std::string state::as(std::string default_value, int index) {
if (lua_isstring(L, index))
return std::string(lua_tostring(L, index), lua_strlen(L, index));
else
return default_value;
}
/** Check an argument of the current function.
* @param narg the argument number to check
*
* This function will throw a lua error if there is no argument at the
* given position.
*
* @note This function is meant to be called from with in a lua::cfunction.
* The error throw is internal to the lua interpreter. When compiled as
* C++, a C++ exception is thrown, so the stack is properly unwound. This
* exception is not meant to be caught.
*/
state& state::check(int narg) {
luaL_checkany(L, narg);
return *this;
}
#ifndef lua_Integer_int
/** Check an argument of the current function.
* @param i the int to hold the returned value
* @param narg the argument number to check
*
* This function checks if the given argument number is an int.
*
* @note This function is meant to be called from with in a
* lua::cfunction. The error throw is internal to the lua intrepeter.
* When compiled as C++, a C++ exception is thrown, so the stack is
* properly unwound. This exception is not meant to be caught.
*/
state& state::check(int& i, int narg) {
i = luaL_checkint(L, narg);
return *this;
}
#endif
/** Check an argument of the current function.
* @param i the lua::integer (lua_Integer) to hold the returned value
* @param narg the argument number to check
*
* This function checks if the given argument number is an integer.
*
* @note This is different from lua::check(int(), ...). It returns a
* lua::integer (lua_Integer), which may not be an int.
*
* @note This function is meant to be called from with in a
* lua::cfunction. The error throw is internal to the lua intrepeter.
* When compiled as C++, a C++ exception is thrown, so the stack is
* properly unwound. This exception is not meant to be caught.
*/
state& state::check(integer& i, int narg) {
i = luaL_checkinteger(L, narg);
return *this;
}
#ifndef lua_Integer_long
/** Check an argument of the current function.
* @param l the long to hold the returned value
* @param narg the argument number to check
*
* This function checks if the given argument number is a long.
*
* @note This function is meant to be called from with in a
* lua::cfunction. The error throw is internal to the lua intrepeter.
* When compiled as C++, a C++ exception is thrown, so the stack is
* properly unwound. This exception is not meant to be caught.
*/
state& state::check(long& l, int narg) {
l = luaL_checklong(L, narg);
return *this;
}
#endif
/** Check an argument of the current function.
* @param s the string to hold the returned value
* @param narg the argument number to check
*
* This function checks if the given argument number is a string.
*
* @note This function is meant to be called from with in a
* lua::cfunction. The error throw is internal to the lua intrepeter.
* When compiled as C++, a C++ exception is thrown, so the stack is
* properly unwound. This exception is not meant to be caught.
*/
state& state::check(std::string& s, int narg) {
const char* c;
size_t l;
c = luaL_checklstring(L, narg, &l);
s.assign(c, l);
return *this;
}
/** Check an argument of the current function.
* @param n the lua::number (lua_Number) to hold the returned value
* @param narg the argument number to check
*
* This function checks if the given argument number is a lua::number
* (lua_Number, a double by default).
*
* @note This function is meant to be called from with in a lua::cfunction.
* The error throw is internal to the lua interpreter. When compiled as
* C++, a C++ exception is thrown, so the stack is properly unwound. This
* exception is not meant to be caught.
*/
state& state::check(number& n, int narg) {
n = luaL_checknumber(L, narg);
return *this;
}
#if 0
/** [specialization] Generate a Lua error (T = std::string).
*/
template<>
void state::error(const std::string& message) {
push(message);
lua_error(L);
}
#endif
/** Call a lua function.
* @param nargs the number of args to pass to the function
* @param nresults the number of values to return from the function
* @param on_error A stack index where the error handling function is
* stored.
* @note The error handling function must be pushed in the stack
* before the function to be called and its arguments.
* @returns a reference to this lua::state
*/
state& state::pcall(int nargs, int nresults, int on_error) {
throw_error(lua_pcall(L, nargs, nresults, on_error));
return *this;
}
/** Call a lua function in unprotected mode.
* @param nargs the number of args to pass to the function
* @param nresults the number of values to return from the function
* stored.
* @note If there is an error in the call the program will terminate.
* @returns a reference to this lua::state
*/
state& state::call(int nargs, int nresults) {
lua_call(L, nargs, nresults);
return *this;
}
/** Ensure the stack is at least the given size.
* @param size the size to use
*
* If the stack is smaller than the given size, it will grow to the
* specified size.
*
* @exception lua::exception Thrown if the operation fails.
* @returns a reference to this lua::state
*/
state& state::checkstack(int size) {
if (!lua_checkstack(L, size))
throw lua::exception("Error growing the stack");
return *this;
}
/** Set a new index as the top of the stack.
* @param index the index to use as the new top
* @note If the previous top was higher than the new one, top values
* are discarded. Otherwise this function pushs nils on to the stack
* to get the proper size.
* @returns a reference to this lua::state
*/
state& state::settop(int index) {
lua_settop(L, index);
return *this;
}
/** Get the number of elements in the stack.
* @note This value is also the index of the top element.
* @returns the number of elements in the stack
*/
int state::gettop() {
return lua_gettop(L);
}
/** Get the number of elements in the stack.
* @note This value is also the index of the top element.
* @returns the number of elements in the stack
*/
int state::size() {
return lua_gettop(L);
}
/** Check if the stack is empty.
* @returns true if the stack is empty, false otherwise
*/
bool state::empty() {
return !lua_gettop(L);
}
/** Move the top element to the given index.
* @param index the index to insert at
* @note All elements on top of the given index are shifted up to open
* space for this element.
* @returns a reference to this lua::state
*/
state& state::insert(int index) {
lua_insert(L, index);
return *this;
}
/** Replace the given index with the top element.
* @param index the index to replae
* @returns a reference to this lua::state
*/
state& state::replace(int index) {
lua_replace(L, index);
return *this;
}
/** Remove the given index from the stack.
* @param index the index to remove
* @note Elements are shifted down to fill in the empty spot.
* @returns a reference to this lua::state
*/
state& state::remove(int index) {
lua_remove(L, index);
return *this;
}
/** Remove the given number of elemens from the stack.
* @param elements the number of elements to remove
* @returns a reference to this lua::state
*/
state& state::pop(int elements) {
lua_pop(L, elements);
return *this;
}
/** Push a copy of the element at the given index to the top of the
* stack.
* @param index the index of the element to copy
* @returns a reference to this lua::state
*/
state& state::pushvalue(int index) {
lua_pushvalue(L, index);
return *this;
}
/** Create a new table on the stack.
* @returns a reference to this lua::state
*/
state& state::newtable() {
lua_newtable(L);
return *this;
}
/** Create a new metatable and add it to the registry.
* @param tname the name to use for the new metatable in the registry
*
* This function creates a new metatable and adds it to the registry
* with the given key. This function also pushes the new metatable
* onto the stack.
*
* @note Regardless of the return value, the new metatable is always pushed
* on to the stack.
*
* @return true if a new metatable was created, false if the registry
* alread has a key with the given name.
*/
bool state::newmetatable(const std::string& tname) {
return luaL_newmetatable(L, tname.c_str());
}
/** Create a new userdatum on the stack.
* @param nbytes the size of the new userdatum
* @return a pointer to the new userdatum
*/
void* state::newuserdata(size_t nbytes) {
return lua_newuserdata(L, nbytes);
}
/** Get a value from a table on the stack.
* @param index the index the table is stored at
*
* This function gets a value from the table at the given index and
* pushes it onto the stack.
*
* @note You should have already pushed the key used to reference this
* value onto the stack before calling this function.
*
* @returns a reference to this lua::state
*/
state& state::gettable(int index) {
lua_gettable(L, index);
return *this;
}
/** Get a value from a table on the stack.
* @param k the key
* @param index the index the table is stored at
*
* This function gets a value from the table at the given index and
* pushes it onto the stack.
*
* @returns a reference to this lua::state
*/
state& state::getfield(const std::string& k, int index) {
lua_getfield(L, index, k.c_str());
return *this;
}
/** Set a value in a table.
* @param index the index the table is stored at
*
* This function sets a value in a table stored at the given index.
*
* @note The key and value to be used should have already been pushed
* on the stack in that order.
*
* @returns a reference to this lua::state
*/
state& state::settable(int index) {
lua_settable(L, index);
return *this;
}
/** Set a field in a table.
* @param k the key
* @param index the index the table is stored at
*
* This function sets a value in a table stored at the given index.
*
* @note The value to be used should be on the top of the stack.
*
* @returns a reference to this lua::state
*/
state& state::setfield(const std::string& k, int index) {
lua_setfield(L, index, k.c_str());
return *this;
}
/** Get the metatable associated with the given registry entry.
* @param tname the name in the registry
*
* This function gets the metatable associated with the given key in
* the registry. The resulting metatable is pushed onto the stack.
*
* @note This function uses luaL_getmetatable() internally.
*
* @returns a reference to this lua::state
*/
state& state::getmetatable(const std::string& tname) {
luaL_getmetatable(L, tname.c_str());
return *this;
}
/** Get the metatable of the value at the given index.
* @param index the index the value is stored at
*
* This function pushes on to the stack the metatabe of the value at
* the given index.
*
* @note This function uses lua_getmetatable() internally.
*
* @returns false if the value at the given index does not have a
* metatable or if the index is not valid
*/
bool state::getmetatable(int index) {
return lua_getmetatable(L, index);
}
/** Get the next key value pair from a table on the stack.
* @param index the stack index the table is at
*
* This function pops a key from the stack and pushes the next key
* value pair to the stack. The key will be stored at index -2 and
* the value will be at index -1. The key is expected to be on the
* top of the stack.
*
* @note While traversing a table, do not call
* lua::state::to(std::string()) directly on a key, unless you know
* that the key is actually a string. lua::state::to(std::string())
* changes the value at the given index; this confuses the next call
* to lua::state::next().
*
* <strong>While Loop Example:</strong>
* @code
* while(L.next() != 0) {
* // do stuff
* L.pop();
* }
* @endcode
*
* <strong>For Loop Example:</strong>
* @code
* for(L.push(lua::nil()); L.next(); L.pop()) {
* // do stuff
* }
* @endcode
*
* @returns true as long as there are remaining items in the table
*/
bool state::next(int index) {
return lua_next(L, index);
}
/** Load a global symbol onto the stack.
* @param name the name of the global to load
*
* This function loads a global symbol onto the stack from the lua
* state.
*
* @returns a reference to this lua::state
*/
state& state::getglobal(const std::string& name) {
lua_getglobal(L, name.c_str());
return *this;
}
/** Set a global symbol.
* @param name the name of the global to set
*
* This function sets/creates a global symbol from the value above it
* on the stack.
*
* @note You should have pushed the value of the symbol onto the stack
* before calling this function.
*
* @returns a reference to this lua::state
*/
state& state::setglobal(const std::string& name) {
lua_setglobal(L, name.c_str());
return *this;
}
/** Load a file as a Lua chunk.
* @param filename the name of the file to load
* @returns a reference to this lua::state
*/
state& state::loadfile(const std::string& filename) {
throw_error(luaL_loadfile(L, filename.c_str()));
return *this;
}
/** Load a string as a Lua chunk.
* @param s the string to load
* @returns a reference to this lua::state
*/
state& state::loadstring(const std::string& s) {
throw_error(luaL_loadstring(L, s.c_str()));
return *this;
}
/** Get the length of a value on the stack.
* @param index the index the value is stored at
* @returns the length of the indicated value
*/
size_t state::objlen(int index) {
return lua_objlen(L, index);
}
/** Get the value at index as a bool.
* @param boolean where to store the value
* @param index the index to get
* @note This function does \em not pop the value from the stack.
* @todo Instead of throwing an exception here, we may just return an
* error code.
* @throws lua::bad_conversion if the value on the stack could not be
* converted to the indicated type
* @returns a reference to this lua::state
*/
template<>
state& state::to(bool& boolean, int index) {
if (lua_isboolean(L, index))
boolean = lua_toboolean(L, index);
else
throw bad_conversion("Cannot convert non 'boolean' value to bool");
return *this;
}
/** Get the value at index as a string.
* @param string where to store the value
* @param index the index to get
* @note This function does \em not pop the value from the stack.
* @todo Instead of throwing an exception here, we may just return an
* error code.
*
* @note lua::state::to(std::string()) will convert the value at the
* indicated index to a string <em>on the stack</em>. This can
* confuse lua::state::next();
*
* @throws lua::bad_conversion if the value on the stack could not be
* converted to the indicated type
* @returns a reference to this lua::state
*/
template<>
state& state::to(std::string& string, int index) {
if (lua_isstring(L, index))
string.replace(0, std::string::npos, lua_tostring(L, index), lua_strlen(L, index));
else
throw bad_conversion("Cannot convert value to string");
return *this;
}
/** Get the value at index as a bool.
* @param default_value this value is returned if the conversion fails
* @param index the index to get
* @note This function does \em not pop the value from the stack.
* @returns the indicated value from the stack or the default value if the
* conversion fails
*/
template<>
bool state::as(bool default_value, int index) {
if (lua_isboolean(L, index))
return lua_toboolean(L, index);
else
return default_value;
}
/** [specialization] Get the value at index as a bool (T = bool).
*/
template<>
bool state::as(int index) {
if (lua_isboolean(L, index))
return lua_toboolean(L, index);
else
throw bad_conversion("Cannot convert non 'boolean' value to bool");
}
/** [specialization] Get the value at index as a string (T = std::string).
* @note lua::state::as(std::string()) will convert the value at the
* indicated index to a string <em>on the stack</em>. This can confuse
* lua::state::next();
*/
template<>
std::string state::as(int index) {
if (lua_isstring(L, index))
return std::string(lua_tostring(L, index), lua_strlen(L, index));
else
throw bad_conversion("Cannot convert value to string");
}
/** [specialization] Check if the given index is a nil (T = lua::nil).
*/
template<>
bool state::is<nil>(int index) {
return lua_isnil(L, index);
}
/** [specialization] Check if the given index is a boolean (T = bool).
*/
template<>
bool state::is<bool>(int index) {
return lua_isboolean(L, index);
}
/** [specialization] Check if the given index is a string (T = std::string).
*/
template<>
bool state::is<std::string>(int index) {
return lua_isstring(L, index);
}
/** [specialization] Check if the given index is a table (T = lua::table).
*/
template<>
bool state::is<table>(int index) {
return lua_istable(L, index);
}
/** [specialization] Check if the given index is a C function (T =
* lua::cfunction).
*/
template<>
bool state::is<cfunction>(int index) {
return lua_iscfunction(L, index);
}
/** [specialization] Check if the given index is a function (T =
* lua::function).
*/
template<>
bool state::is<function>(int index) {
return lua_isfunction(L, index);
}
/** [specialization] Check if the given index is userdata (T =
* lua::userdata).
*/
template<>
bool state::is<userdata>(int index) {
return lua_isuserdata(L, index);
}
/** [specialization] Check if the given index is light userdata (T =
* lua::lightuserdata).
*/
template<>
bool state::is<lightuserdata>(int index) {
return lua_islightuserdata(L, index);
}
}