Mercurial > hg > orthanc
view Core/Lua/LuaFunctionCall.cpp @ 1352:382439943749
ResourceFinder
author | Sebastien Jodogne <s.jodogne@gmail.com> |
---|---|
date | Mon, 11 May 2015 17:25:53 +0200 |
parents | 6e7e5ed91c2d |
children | 3f7722179467 |
line wrap: on
line source
/** * Orthanc - A Lightweight, RESTful DICOM Store * Copyright (C) 2012-2015 Sebastien Jodogne, Medical Physics * Department, University Hospital of Liege, Belgium * * 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 3 of the * License, or (at your option) any later version. * * In addition, as a special exception, the copyright holders of this * program give permission to link the code of its release with the * OpenSSL project's "OpenSSL" library (or with modified versions of it * that use the same license as the "OpenSSL" library), and distribute * the linked executables. You must obey the GNU General Public License * in all respects for all of the code used other than "OpenSSL". If you * modify file(s) with this exception, you may extend this exception to * your version of the file(s), but you are not obligated to do so. If * you do not wish to do so, delete this exception statement from your * version. If you delete this exception statement from all source files * in the program, then also delete it here. * * 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, see <http://www.gnu.org/licenses/>. **/ #include "../PrecompiledHeaders.h" #include "LuaFunctionCall.h" #include <cassert> #include <stdio.h> #include <boost/lexical_cast.hpp> #include <glog/logging.h> namespace Orthanc { void LuaFunctionCall::CheckAlreadyExecuted() { if (isExecuted_) { throw LuaException("Arguments cannot be pushed after the function is executed"); } } LuaFunctionCall::LuaFunctionCall(LuaContext& context, const char* functionName) : context_(context), isExecuted_(false) { // Clear the stack to fulfill the invariant lua_settop(context_.lua_, 0); lua_getglobal(context_.lua_, functionName); } void LuaFunctionCall::PushString(const std::string& value) { CheckAlreadyExecuted(); lua_pushstring(context_.lua_, value.c_str()); } void LuaFunctionCall::PushBoolean(bool value) { CheckAlreadyExecuted(); lua_pushboolean(context_.lua_, value); } void LuaFunctionCall::PushInteger(int value) { CheckAlreadyExecuted(); lua_pushinteger(context_.lua_, value); } void LuaFunctionCall::PushDouble(double value) { CheckAlreadyExecuted(); lua_pushnumber(context_.lua_, value); } void LuaFunctionCall::PushJson(const Json::Value& value) { CheckAlreadyExecuted(); context_.PushJson(value); } void LuaFunctionCall::ExecuteInternal(int numOutputs) { CheckAlreadyExecuted(); assert(lua_gettop(context_.lua_) >= 1); int nargs = lua_gettop(context_.lua_) - 1; int error = lua_pcall(context_.lua_, nargs, numOutputs, 0); if (error) { assert(lua_gettop(context_.lua_) >= 1); std::string description(lua_tostring(context_.lua_, -1)); lua_pop(context_.lua_, 1); /* pop error message from the stack */ throw LuaException(description); } if (lua_gettop(context_.lua_) < numOutputs) { throw LuaException("The function does not give the expected number of outputs"); } isExecuted_ = true; } bool LuaFunctionCall::ExecutePredicate() { ExecuteInternal(1); if (!lua_isboolean(context_.lua_, 1)) { throw LuaException("The function is not a predicate (only true/false outputs allowed)"); } return lua_toboolean(context_.lua_, 1) != 0; } static void PopJson(Json::Value& result, lua_State* lua, int top) { if (lua_istable(lua, top)) { Json::Value tmp = Json::objectValue; bool isArray = true; size_t size = 0; // http://stackoverflow.com/a/6142700/881731 // Push another reference to the table on top of the stack (so we know // where it is, and this function can work for negative, positive and // pseudo indices lua_pushvalue(lua, top); // stack now contains: -1 => table lua_pushnil(lua); // stack now contains: -1 => nil; -2 => table while (lua_next(lua, -2)) { // stack now contains: -1 => value; -2 => key; -3 => table // copy the key so that lua_tostring does not modify the original lua_pushvalue(lua, -2); // stack now contains: -1 => key; -2 => value; -3 => key; -4 => table std::string key(lua_tostring(lua, -1)); Json::Value v; PopJson(v, lua, -2); tmp[key] = v; size += 1; try { if (boost::lexical_cast<size_t>(key) != size) { isArray = false; } } catch (boost::bad_lexical_cast&) { isArray = false; } // pop value + copy of key, leaving original key lua_pop(lua, 2); // stack now contains: -1 => key; -2 => table } // stack now contains: -1 => table (when lua_next returns 0 it pops the key // but does not push anything.) // Pop table lua_pop(lua, 1); // Stack is now the same as it was on entry to this function if (isArray) { result = Json::arrayValue; for (size_t i = 0; i < size; i++) { result.append(tmp[boost::lexical_cast<std::string>(i + 1)]); } } else { result = tmp; } } else if (lua_isnumber(lua, top)) { result = static_cast<float>(lua_tonumber(lua, top)); } else if (lua_isstring(lua, top)) { result = std::string(lua_tostring(lua, top)); } else if (lua_isboolean(lua, top)) { result = static_cast<bool>(lua_toboolean(lua, top)); } else { LOG(WARNING) << "Unsupported Lua type when returning Json"; result = Json::nullValue; } } void LuaFunctionCall::ExecuteToJson(Json::Value& result) { ExecuteInternal(1); PopJson(result, context_.lua_, lua_gettop(context_.lua_)); } }