判断分区是否为ext4文件系统



判断分区中是否有ext4文件系统：

static int ckext4(char *fsdev)

{

int fd;

int ret;

struct ext4_super_block sb;

 

//if (setjmp(setjmp_env))

//return -1;

fd = open(fsdev, O_RDWR);

if (fd < 0)

return -1;

ret = lseek64(fd, 1024, SEEK_SET);

if (ret < 0)

goto ckext4_fs_error;

ret = read(fd, &sb, sizeof(sb));

if (ret < 0)

goto ckext4_fs_error;

if (ret != sizeof(sb))

goto ckext4_fs_error;

if (sb.s_magic != EXT4_SUPER_MAGIC)

goto ckext4_sbmagic_error;

if ((sb.s_state & EXT4_VALID_FS) != EXT4_VALID_FS)

goto ckext4_sbstatus_error;

if(sb.s_feature_incompat & EXT4_FEATURE_INCOMPAT_RECOVER==0)

goto ckext4_needrecovery_error;

close(fd);

return 0;

 

ckext4_fs_error:

close(fd);

return -2;

ckext4_sbmagic_error:

close(fd);

return -3;

ckext4_sbstatus_error:

close(fd);

return -4;

ckext4_needrecovery_error:

close(fd);

return -5;

}