franta-hg@1: /**
franta-hg@1:  * cpp-finally
franta-hg@1:  * Copyright © 2024 František Kučera (Frantovo.cz, GlobalCode.info)
franta-hg@1:  *
franta-hg@1:  * This program is free software: you can redistribute it and/or modify
franta-hg@1:  * it under the terms of the GNU General Public License as published by
franta-hg@1:  * the Free Software Foundation, version 3 of the License.
franta-hg@1:  *
franta-hg@1:  * This program is distributed in the hope that it will be useful,
franta-hg@1:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@1:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@1:  * GNU General Public License for more details.
franta-hg@1:  *
franta-hg@1:  * You should have received a copy of the GNU General Public License
franta-hg@1:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@1:  */
franta-hg@1: 
franta-hg@0: #include <iostream>
franta-hg@0: #include <exception>
franta-hg@0: 
franta-hg@0: template<typename T>
franta-hg@0: class Resource {
franta-hg@0: private:
franta-hg@0: 	Resource(const Resource&) = delete;
franta-hg@0: 	Resource& operator=(const Resource&) = delete;
franta-hg@0: public:
franta-hg@0: 	T* data;
franta-hg@0: 	void(*dtor)(T*);
franta-hg@0: 
franta-hg@0: 	Resource(T* data, void(*dtor)(T*)) : data(data), dtor(dtor) {
franta-hg@0: 		std::cout << "  created resource for data at: " << data << std::endl;
franta-hg@0: 	}
franta-hg@0: 
franta-hg@0: 	virtual ~Resource() {
franta-hg@0: 		dtor(data);
franta-hg@0: 		std::cout << "  called destructor on: " << data << std::endl;
franta-hg@0: 	}
franta-hg@0: };
franta-hg@0: 
franta-hg@0: void fxThrowing(bool fail, void* data) {
franta-hg@0: 	std::cout << "  doing something with data " << data << std::endl;
franta-hg@0: 	if (fail) throw std::logic_error("error from fxThrowing()");
franta-hg@0: }
franta-hg@0: 
franta-hg@0: void fxAllocating(bool fail) {
franta-hg@0: 	Resource buf(malloc(486), free);
franta-hg@0: 	fxThrowing(fail, buf.data);
franta-hg@0: }
franta-hg@0: 
franta-hg@0: int main(int argc, char** argv) {
franta-hg@0: 	bool fail = argc == 2 && std::string("fail") == argv[1];
franta-hg@0: 	const char* name = "good-class-generic";
franta-hg@0: 	std::cout << name << " (fail=" << fail << ")\n";
franta-hg@0: 	try {
franta-hg@0: 		fxAllocating(fail);
franta-hg@0: 	} catch (const std::exception& e) {
franta-hg@0: 		std::cout << "  caught exception: " << e.what() << std::endl;
franta-hg@0: 	}
franta-hg@0: }