1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
/*
* This code is based on Broken Sword 2.5 engine
*
* Copyright (c) Malte Thiesen, Daniel Queteschiner and Michael Elsdoerfer
*
* Licensed under GNU GPL v2
*
*/
#include "common/textconsole.h"
#include "sword25/script/luacallback.h"
#include "sword25/script/luabindhelper.h"
#include "sword25/util/lua/lua.h"
#include "sword25/util/lua/lauxlib.h"
const char *CALLBACKTABLE_NAME = "__CALLBACKS";
namespace Sword25 {
LuaCallback::LuaCallback(lua_State *L) {
// Create callback table
lua_newtable(L);
lua_setglobal(L, CALLBACKTABLE_NAME);
}
LuaCallback::~LuaCallback() {
}
void LuaCallback::registerCallbackFunction(lua_State *L, uint objectHandle) {
assert(lua_isfunction(L, -1));
ensureObjectCallbackTableExists(L, objectHandle);
// Store function in the callback object table store
lua_pushvalue(L, -2);
luaL_ref(L, -2);
// Pop the function and object callback table from the stack
lua_pop(L, 2);
}
void LuaCallback::unregisterCallbackFunction(lua_State *L, uint objectHandle) {
assert(lua_isfunction(L, -1));
ensureObjectCallbackTableExists(L, objectHandle);
// Iterate over all elements of the object callback table and remove the function from it
lua_pushnil(L);
while (lua_next(L, -2) != 0) {
// The value of the current element is the top of the stack, including the index
// If the value is identical to the function parameters, it is removed from the table
if (lua_equal(L, -1, -4)) {
lua_pushvalue(L, -2);
lua_pushnil(L);
lua_settable(L, -5);
// The function was found, iteration can be stopped
lua_pop(L, 2);
break;
} else {
// Pop value from the stack. The index is then ready for the next call to lua_next()
lua_pop(L, 1);
}
}
// Function and object table are popped from the stack
lua_pop(L, 2);
}
void LuaCallback::removeAllObjectCallbacks(lua_State *L, uint objectHandle) {
pushCallbackTable(L);
// Remove the object callback from the callback table
lua_pushnumber(L, objectHandle);
lua_pushnil(L);
lua_settable(L, -3);
lua_pop(L, 1);
}
void LuaCallback::invokeCallbackFunctions(lua_State *L, uint objectHandle) {
ensureObjectCallbackTableExists(L, objectHandle);
// Iterate through the table and perform all the callbacks
lua_pushnil(L);
while (lua_next(L, -2) != 0) {
// The value of the current element is at the top of the stack, including the index
// If the value is a function, execute it
if (lua_type(L, -1) == LUA_TFUNCTION) {
// Pre-Function Call
// Derived classes can function in this parameter onto the stack.
// The return value indicates the number of parameters
int argumentCount = preFunctionInvokation(L);
// Lua_pcall the function and the parameters pop themselves from the stack
if (lua_pcall(L, argumentCount, 0, 0) != 0) {
// An error has occurred
error("An error occurred executing a callback function: %s", lua_tostring(L, -1));
// Pop error message from the stack
lua_pop(L, 1);
}
} else {
// Pop value from the stack. The index is then ready for the next call to lua_next()
lua_pop(L, 1);
}
}
}
void LuaCallback::ensureObjectCallbackTableExists(lua_State *L, uint objectHandle) {
pushObjectCallbackTable(L, objectHandle);
// If the table is nil, it must first be created
if (lua_isnil(L, -1)) {
// Pop nil from stack
lua_pop(L, 1);
pushCallbackTable(L);
// Create the table, and put the objectHandle into it
lua_newtable(L);
lua_pushnumber(L, objectHandle);
lua_pushvalue(L, -2);
lua_settable(L, -4);
// Pop the callback table from the stack
lua_remove(L, -2);
}
}
void LuaCallback::pushCallbackTable(lua_State *L) {
lua_getglobal(L, CALLBACKTABLE_NAME);
}
void LuaCallback::pushObjectCallbackTable(lua_State *L, uint objectHandle) {
pushCallbackTable(L);
// Push Object Callback table onto the stack
lua_pushnumber(L, objectHandle);
lua_gettable(L, -2);
// Pop the callback table from the stack
lua_remove(L, -2);
}
} // End of namespace Sword25
|
