daemon.cc

#include "daemon.h"
#include "log.h"
#include "config.h"
#include <time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sstream>

namespace sylar {

static sylar::Logger::ptr g_logger = SYLAR_LOG_NAME("system");
static sylar::ConfigVar<uint32_t>::ptr g_daemon_restart_interval
	= sylar::Config::Lookup("daemon.restart_interval", (uint32_t)5,
			"daemon restart interval");

std::string ProcessInfo::toString() const  {
	std::stringstream ss;
	ss << "[ProcessInfo parent_id=" << parent_id
	   << " main_id = " << main_id 
	   << " parent_start_time=" << sylar::Time2Str(parent_start_time)
	   << "main_start_time=" << sylar::Time2Str(main_start_time)
	   << " restart_count=" << restart_count << "]";
	return ss.str();
}

static int real_start(int argc, char** argv
					,std::function<int(int argc, char** argv)> main_cb) {
	return main_cb(argc, argv);
}


static int real_daemon(int argc, char** argv
					,std::function<int(int argc, char** argv)> main_cb) {
	daemon(1, 0);
	ProcessInfoMgr::GetInstence()->parent_id = getpid();
	ProcessInfoMgr::GetInstence()->parent_start_time = time(0);
	while(true) {
		pid_t pid = fork();
		if(pid == 0) {
			//子进程返回
			ProcessInfoMgr::GetInstence()->main_id = getpid();
			ProcessInfoMgr::GetInstence()->main_start_time = time(0);
			SYLAR_LOG_INFO(g_logger) << "process start pid=" << getpid();
			return real_start(argc, argv, main_cb);
		} else if(pid < 0) {
			SYLAR_LOG_ERROR(g_logger) << "fork fail return=" << pid
				<< " errno=" << errno << " errstr=" << strerror(errno);
			return -1;
		} else {
			//父进程返回
			int status = 0;
			waitpid(pid, &status, 0);
			if(status) {
				SYLAR_LOG_ERROR(g_logger) << "child crash pid=" << pid
					<< " status=" << status;			
			} else {
			
				SYLAR_LOG_INFO(g_logger) << "child finished pid=" << pid;
				break;
			}
			ProcessInfoMgr::GetInstence()->restart_count += 1;
			sleep(g_daemon_restart_interval->getValue());
		}
	}
	return 0;
}


int start_daemon(int argc, char** argv
				,std::function<int(int argc, char** argv)> main_cb
				,bool is_daemon) {
	if(!is_daemon) {
		return real_start(argc, argv, main_cb);
	}

	return real_daemon(argc, argv, main_cb);
}


}