给定一个硬盘标识，umout掉所有相关挂载

#include <fcntl.h>
 #include <string.h>
 #include <assert.h>
 #include <pthread.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <errno.h>
 #include <stdio.h>
 #include <linux/reboot.h>
 #include <dirent.h>
 #include <sys/mount.h>
 
 //def for bool
 #ifndef bool //8bit
 #define bool unsigned char
 #endif
 #ifndef NULL
 #define NULL ((void*)0)
 #endif
 #ifndef false
 #define false 0
 #endif
 #ifndef true
 #define true 1
 #endif
 //end of def for bool
 
 /*
  * check file is exist!!
  */
 static bool file_exist(const char* path)
 {
 
     if(!path) return false;
     if(access(path,F_OK) == 0)
     {
         return true;//file exist
     }
     printf("[Info] file:%s is not exist!\n",path);
     return false ; //file is not exist
 
 }
 static int umount_disk_partition(const char* disk)
 {
     if(!disk)
         return 0;
     
 #define MOUNTS_FILE_SIZE  2048
     const char* mounts = "/proc/self/mounts";
     const char* delims = " ";
 
     bool bug = true;
     char buf[MOUNTS_FILE_SIZE] = {0};
     int fd,ret = 0;
     int row = 0;
     char *start = NULL,*end = NULL,*lineend = NULL,*cp = NULL,*result = NULL;

     if((fd = open(mounts,O_RDONLY)) < 0)
     {
         perror("open error:");
         return -1;
     }
     if(lseek(fd,0,SEEK_SET) == (off_t)-1)
     {
         printf("lseek: %s (%d)\n", strerror(errno), errno);
         close(fd);
         return -1;
     }
     if((ret = read(fd,buf,sizeof(buf)-1)) < 0 )
     {
         perror("read error:");
         close(fd);
         return -1;
     }
     close(fd);
     end = buf + ret;
     *end = 0;
     start = buf;
     while(start < end)
     {
         lineend = strchr(start,'\0');
         if(!lineend)
             break;
         *lineend = 0;
         
         cp = strstr(start,disk);
         if(!cp) 
         {
             start = lineend + 1;
             continue;
         }
         
         result = strtok(cp,delims);
         row = 0;
         while(result)
         {
             if(row == 1)
             {
                 bug && printf("mount points:%s \n",result);
                 umount2(result,MNT_FORCE);
                 break;
             }
             row++;
             result = strtok(NULL,delims);
         }
         start = cp + 1;
     }
     
     
     return 0;
 }
 main()
 {
     umount_disk_partition("/dev/mtdblock");
 }