comparison Core/Lua/LuaFunctionCall.cpp @ 386:7dec4f3c922c lua-scripting

lua wrapper
author Sebastien Jodogne <s.jodogne@gmail.com>
date Mon, 29 Apr 2013 17:14:10 +0200
parents
children 08eca5d86aad
comparison
equal deleted inserted replaced
384:18fe778eeb95 386:7dec4f3c922c
1 /**
2 * Orthanc - A Lightweight, RESTful DICOM Store
3 * Copyright (C) 2012-2013 Medical Physics Department, CHU of Liege,
4 * Belgium
5 *
6 * This program is free software: you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License as
8 * published by the Free Software Foundation, either version 3 of the
9 * License, or (at your option) any later version.
10 *
11 * In addition, as a special exception, the copyright holders of this
12 * program give permission to link the code of its release with the
13 * OpenSSL project's "OpenSSL" library (or with modified versions of it
14 * that use the same license as the "OpenSSL" library), and distribute
15 * the linked executables. You must obey the GNU General Public License
16 * in all respects for all of the code used other than "OpenSSL". If you
17 * modify file(s) with this exception, you may extend this exception to
18 * your version of the file(s), but you are not obligated to do so. If
19 * you do not wish to do so, delete this exception statement from your
20 * version. If you delete this exception statement from all source files
21 * in the program, then also delete it here.
22 *
23 * This program is distributed in the hope that it will be useful, but
24 * WITHOUT ANY WARRANTY; without even the implied warranty of
25 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
26 * General Public License for more details.
27 *
28 * You should have received a copy of the GNU General Public License
29 * along with this program. If not, see <http://www.gnu.org/licenses/>.
30 **/
31
32
33 #include "LuaFunctionCall.h"
34
35
36 namespace Orthanc
37 {
38 void LuaFunctionCall::CheckAlreadyExecuted()
39 {
40 if (isExecuted_)
41 {
42 throw LuaException("Arguments cannot be pushed after the function is executed");
43 }
44 }
45
46 LuaFunctionCall::LuaFunctionCall(LuaContext& context,
47 const char* functionName) :
48 context_(context),
49 lock_(context.mutex_),
50 isExecuted_(false)
51 {
52 // Clear the stack to fulfill the invariant
53 lua_settop(context_.lua_, 0);
54 lua_getglobal(context_.lua_, functionName);
55 }
56
57 void LuaFunctionCall::PushString(const std::string& value)
58 {
59 CheckAlreadyExecuted();
60 lua_pushstring(context_.lua_, value.c_str());
61 }
62
63 void LuaFunctionCall::PushBoolean(bool value)
64 {
65 CheckAlreadyExecuted();
66 lua_pushboolean(context_.lua_, value);
67 }
68
69 void LuaFunctionCall::PushInteger(int value)
70 {
71 CheckAlreadyExecuted();
72 lua_pushinteger(context_.lua_, value);
73 }
74
75 void LuaFunctionCall::PushDouble(double value)
76 {
77 CheckAlreadyExecuted();
78 lua_pushnumber(context_.lua_, value);
79 }
80
81 void LuaFunctionCall::PushJSON(const Json::Value& value)
82 {
83 CheckAlreadyExecuted();
84
85 if (value.isString())
86 {
87 lua_pushstring(context_.lua_, value.asCString());
88 }
89 else if (value.isDouble())
90 {
91 lua_pushnumber(context_.lua_, value.asDouble());
92 }
93 else if (value.isInt())
94 {
95 lua_pushinteger(context_.lua_, value.asInt());
96 }
97 else if (value.isUInt())
98 {
99 lua_pushinteger(context_.lua_, value.asUInt());
100 }
101 else if (value.isBool())
102 {
103 lua_pushboolean(context_.lua_, value.asBool());
104 }
105 else if (value.isNull())
106 {
107 lua_pushnil(context_.lua_);
108 }
109 else if (value.isArray())
110 {
111 lua_newtable(context_.lua_);
112
113 // http://lua-users.org/wiki/SimpleLuaApiExample
114 for (Json::Value::ArrayIndex i = 0; i < value.size(); i++)
115 {
116 // Push the table index (note the "+1" because of Lua conventions)
117 lua_pushnumber(context_.lua_, i + 1);
118
119 // Push the value of the cell
120 PushJSON(value[i]);
121
122 // Stores the pair in the table
123 lua_rawset(context_.lua_, -3);
124 }
125 }
126 else if (value.isObject())
127 {
128 lua_newtable(context_.lua_);
129
130 Json::Value::Members members = value.getMemberNames();
131
132 for (Json::Value::Members::const_iterator
133 it = members.begin(); it != members.end(); it++)
134 {
135 // Push the index of the cell
136 lua_pushstring(context_.lua_, it->c_str());
137
138 // Push the value of the cell
139 PushJSON(value[*it]);
140
141 // Stores the pair in the table
142 lua_rawset(context_.lua_, -3);
143 }
144 }
145 else
146 {
147 throw LuaException("Unsupported JSON conversion");
148 }
149 }
150
151 void LuaFunctionCall::Execute(int numOutputs)
152 {
153 CheckAlreadyExecuted();
154
155 assert(lua_gettop(context_.lua_) >= 1);
156 int nargs = lua_gettop(context_.lua_) - 1;
157 int error = lua_pcall(context_.lua_, nargs, numOutputs, 0);
158
159 if (error)
160 {
161 assert(lua_gettop(context_.lua_) >= 1);
162
163 std::string description(lua_tostring(context_.lua_, -1));
164 lua_pop(context_.lua_, 1); /* pop error message from the stack */
165 throw LuaException(description);
166 }
167
168 if (lua_gettop(context_.lua_) < numOutputs)
169 {
170 throw LuaException("The function does not give the expected number of outputs");
171 }
172
173 isExecuted_ = true;
174 }
175
176 bool LuaFunctionCall::ExecutePredicate()
177 {
178 Execute(1);
179
180 if (lua_gettop(context_.lua_) == 0)
181 {
182 throw LuaException("No output was provided by the function");
183 }
184
185 if (!lua_isboolean(context_.lua_, 1))
186 {
187 throw LuaException("The function is not a predicate (only true/false outputs allowed)");
188 }
189
190 return lua_toboolean(context_.lua_, 1) != 0;
191 }
192 }