fork.cc
c102ec9084d7master

fork.cc
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			#include "include/fork.h"

			#include <cstdlib>
			#include <cstring>
			#include <iostream>
			#include <stdexcept>
			#include <unistd.h>

			#ifdef _WIN32
			#include <windows.h>
			#else
			#include <pwd.h>
			#include <unistd.h>
			#endif

			using namespace std;

			std::string home() {
			#ifdef _WIN32
			const char *userProfile = std::getenv("USERPROFILE");
			if (userProfile) {
			return std::string(userProfile);
			} else {
			return "";
			}
			#else
			struct passwd *pw = getpwuid(getuid());
			if (pw && pw->pw_dir) {
			return std::string(pw->pw_dir);
			} else {
			return "";
			}
			#endif
			}

			Fork fork_process() {
			pid_t res = ::fork();
			if (res == -1) {
			perror("fork_process");
			throw std::runtime_error("fork() failed");
			} else if (res == 0) {
			return Fork::Child;
			} else {
			return Fork::Parent;
			}
			}

			pid_t set_sid() {
			pid_t res = ::setsid();
			if (res == -1) {
			perror("set_sid");
			throw std::runtime_error("setsid() failed");
			}
			return res;
			}

			void close_fd() {
			bool res = false;
			for (int i = 0; i <= 2; ++i) {
			res \|= (::close(i) == -1);
			}

			if (res) {
			perror("close_fd");
			throw std::runtime_error("close_fd() failed");
			}
			}

			int32_t try_fork(bool nochdir, bool noclose, Callback callback) {
			try {
			Fork forkResult = fork_process();
			if (forkResult == Fork::Parent) {
			exit(0);
			} else if (forkResult == Fork::Child) {
			set_sid();
			if (!nochdir) {
			std::string home_dir = home() + ".pmc";
			chdir(home_dir.c_str());
			}
			if (!noclose) {
			close_fd();
			}
			forkResult = fork_process();
			}
			return static_cast<int32_t>(forkResult);
			} catch (const std::exception &e) {
			std::cerr << "[PMC] (cc) Error setting up daemon handler\n";
			perror("try_fork");
			}

			callback();
			return -1;
			}