callExtension

Game1 needed - Version1 needed1.000.50

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Description

Description:

Description needed

Groups:

System

Syntax

Syntax:

Syntax needed

Parameters:

extension: String - extension name

function: String - data sent to the extension

Return Value:

Return value needed

Alternative Syntax

Syntax:

extension callExtension [function, arguments] Template:Since

Parameters:

extension: String - extension name

function: String - extension function identifier

arguments: Array - function arguments. Could be array of Anything, each element will be converted to String automatically. Current allowed max length of this array is 2048 (since Arma 3 v1.92; previous limit: 1024)

Return Value:

Array - in format [result, returnCode, errorCode], where:

• result: String - data sent back from extension. It is up to extension maker what it is.
• returnCode: Number - integer return from extension method. It is up to extension maker to define it.
• errorCode: Number - error code in case of command error (see description). 0 means no errors.

Examples

Example 1:

_return = "myExtension" callExtension "stringToBeParsed";

Example 2:

_result = "test_extension" callExtension str weapons player; _result = "test_extension" callExtension ["fnc1", getUnitLoadout player]; _result = "test_extension" callExtension ["fnc2", magazinesAmmoFull player]; _result = "test_extension" callExtension ["fnc1", [weapons player, magazines player]];

Example 3:

_result = "test_extension" callExtension ["fnc1", [1,"two",true,[4,"five",false]]]; parseSimpleArray (_result select 0) params ["_number","_string","_boolean","_array"]; systemChat str [_number,_string,_boolean,_array];
Source Code (Download .dll)

This is an example of an extension compatible with both syntaxes. When using 1st syntax, the data is just copied from input to output. When using alt syntax, the arguments are parsed and then assembled back into string array in 2 ways: fnc1 and fnc2. fnc1 is a fraction faster.

#include <string>
#include <vector>
#include <iterator>
#include <sstream>

#define CURRENT_VERSION "1.0.0.1"

extern "C"
{
	//--- Engine called on extension load 
	__declspec (dllexport) void __stdcall RVExtensionVersion(char *output, int outputSize);
	//--- STRING callExtension STRING
	__declspec (dllexport) void __stdcall RVExtension(char *output, int outputSize, const char *function);
	//--- STRING callExtension ARRAY
	__declspec (dllexport) int __stdcall RVExtensionArgs(char *output, int outputSize, const char *function, const char **args, int argsCnt);
}

//--- Extension version information shown in .rpt file
void __stdcall RVExtensionVersion(char *output, int outputSize)
{
	//--- max outputSize is 32 bytes
	strncpy_s(output, outputSize, CURRENT_VERSION, _TRUNCATE);
}

//--- name callExtension function
void __stdcall RVExtension(char *output, int outputSize, const char *function)
{
	std::string str = function;
	strncpy_s(output, outputSize, ("Input Was: " + str).c_str(), _TRUNCATE);
}

//--- name callExtension [function, args]
int __stdcall RVExtensionArgs(char *output, int outputSize, const char *function, const char **args, int argsCnt)
{
	if (strcmp(function, "fnc1") == 0)
	{
		//--- Manually assemble output array
		int i = 0;
		std::string str = "[";

		//--- Each argument can be accessed via args[n]
		if (argsCnt > 0)
			str += args[i++];

		while (i < argsCnt)
		{
			str += ",";
			str += args[i++];
		}

		str += "]";

		//--- Extension result
		strncpy_s(output, outputSize, str.c_str(), _TRUNCATE);

		//--- Extension return code
		return 100;
	}

	else if (strcmp(function, "fnc2") == 0)
	{
		//--- Parse args into vector
		std::vector<std::string> vec(args, std::next(args, argsCnt));

		std::ostringstream oss;
		if (!vec.empty())
		{
			//--- Assemble output array
			std::copy(vec.begin(), vec.end() - 1, std::ostream_iterator<std::string>(oss, ","));
			oss << vec.back();
		}

		//--- Extension result
		strncpy_s(output, outputSize, ("[" + oss.str() + "]").c_str(), _TRUNCATE);

		//--- Extension return code
		return 200;
	}

	else
	{
		strncpy_s(output, outputSize, "Avaliable Functions: fnc1, fnc2", outputSize - 1);
		return -1;
	}
}

Example 4:

fncToExecute_1 = { hint format ["Extension Result 1: %1", _this] };

fncToExecute_2 = { hint format ["Extension Result 2: %1", _this] }; fncToExecute_3 = { hint format ["Extension Result 3: %1", _this] };

addMissionEventHandler ["ExtensionCallback", { params ["_name", "_function", "_data"]; if (_name isEqualTo "test_callback") then { parseSimpleArray _data call (missionNamespace getVariable [_function, { hint "Function does not exist!" }]); }; }];

"test_callback" callExtension str "test data";
Here is a minimal example of an extension utilising extension callback (don't actually do it like this). fncToExecute_X function is called from "ExtensionCallback" event handler when it is triggered after 2 seconds of the extension call.

#include <thread>
#include <string>
#include <chrono>

extern "C"
{
	__declspec (dllexport) void __stdcall RVExtensionRegisterCallback(int(*callbackProc)(char const *name, char const *function, char const *data));
	__declspec (dllexport) void __stdcall RVExtension(char *output, int outputSize, const char *function);
}

int(*callbackPtr)(char const *name, char const *function, char const *data) = nullptr;

void __stdcall RVExtensionRegisterCallback(int(*callbackProc)(char const *name, char const *function, char const *data))
{
	callbackPtr = callbackProc;
}

void __stdcall RVExtension(char *output, int outputSize, const char *function)
{
	if (!callbackPtr)
		return;

	std::thread ([](std::string fnc)
	{		
		using namespace std::chrono_literals;
		fnc = "[1,2,3," + fnc + "]";

		for (int i = 1; i < 4; ++i) // run 3 times
		{
			std::this_thread::sleep_for(2s); // sleep for 2 seconds
			callbackPtr("test_callback", ("fncToExecute_" + std::to_string(i)).c_str(), fnc.c_str());
		}

	}, function).detach();
}

Additional Information

See also:

callcompileparseSimpleArrayExtensions

Notes

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