#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <ctype.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/wait.h>
#define PROC_NAME "mymail"
#define EXEC_NAME "/root/dev_mobile/source/MyMail/src/mymail"
#define LOCKFILE "/root/mytest.lock"
#define DEBUG
int daemon_init()
{
struct sigaction act;
int i, maxfd;
int lock_fd;
int ret;
char buf[100];
lock_fd=open(LOCKFILE,O_RDWR|O_CREAT,0640);
if(lock_fd<0){
printf("lockfile failed :\n");
exit(-1);
}
ret=flock(lock_fd,LOCK_EX|LOCK_NB);//因为下面关闭了,所以起不到作用
if(ret<0){
printf("can't obtaion the file lock:\n");
exit(0);
}
if (fork() != 0)
exit(0);
if (setsid() < 0)
return -1;
act.sa_handler = SIG_IGN;
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGHUP, &act, 0);
if (fork() != 0)
exit(0);
chdir("/");
umask(0);
setpgrp();
maxfd = sysconf(_SC_OPEN_MAX);
for (i = 0; i < maxfd; i++)
//close(i);
;
sprintf(buf,"%6d\n",getpid());
write(lock_fd,buf,strlen(buf));
open("/dev/null", O_RDWR);
dup(0);
dup(1);
dup(2);
return 0;
}
static int file2str(char *filename, char *ret, int cap)
{
int fd, num_read;
if ((fd = open(filename, O_RDONLY, 0)) == -1)
return -1;
if ((num_read = read(fd, ret, cap - 1)) <= 0)
return -1;
ret[num_read] = 0;
close(fd);
return num_read;
}
static int parse_proc_status(char*p_name,char *S)
{
char *tmp;
unsigned char p_id[10];
memset(p_id, 0x00, sizeof(p_id));
sscanf(S, "Name:\t%15c", p_id);
tmp = strchr(p_id, '\n');
if (tmp)
*tmp = '\0';
//printf("%s\n",p_id);
if(strcmp(p_name,p_id)==0)
return 0;
else
return -1;
return -1;
}
static int proc_exist(char *p_name)
{
DIR *dir;
FILE *file;
struct dirent *entry;
char path[32], sbuf[512];
int id;
dir = opendir("/proc");
if (!dir){
perror("Can't open /proc");
exit(-1);
}
while ((entry = readdir(dir)) != NULL) {
if (!isdigit(*entry->d_name))
continue;
sprintf(path, "/proc/%s/status", entry->d_name);
if ((file2str(path, sbuf, sizeof sbuf)) != -1) {
if(parse_proc_status(p_name,sbuf)==0){
id=atol(entry->d_name);
printf("id=%d\n",id);
closedir(dir);
return 0;
}
}
}
closedir(dir);
return -1;
}
static int proc_fork(char*p_path)
{
char * argv[ ]={PROC_NAME,(char*)0 };
pid_t pid;
pid=fork();
if(pid==0){
execv(p_path,argv);
}
if(pid>0)
printf("fork succeed:\n");
}
void handler()
{
char uidName[30];
char exec_path[50];
memset(uidName,0x00,sizeof(uidName));
memset(exec_path,0x00,sizeof(exec_path));
strcpy(uidName,PROC_NAME);
strcpy(exec_path,EXEC_NAME);
printf("one\n");
if (proc_exist(uidName)==0)
printf("进程存在\n");
else
proc_fork(exec_path);
alarm(10);
}
int main(int argc, char **argv)
{
#ifdef DEBUG
if (daemon_init() < 0) {
printf("daemon failed\n");
return 1;
}
#endif
signal(SIGALRM,handler);
alarm(15);
while (1){
while ( waitpid(-1,NULL,WNOHANG) > 0)
printf("test:\n");
}
}
网上的unix比较多，前几天做了一个linux下的，监控某一程序，如果不存在，就启动。 |
