如何读取git-ls-tree输出的模式字段?

浏览 7关注 0回答 2得票数 0
原文
$ git ls-tree fb3a8bdd0ce
100644 blob 63c918c667fa005ff12ad89437f2fdc80926e21c    .gitignore
100644 blob 5529b198e8d14decbe4ad99db3f7fb632de0439d    .mailmap
100644 blob 6ff87c4664981e4397625791c8ea3bbb5f2279a3    COPYING
040000 tree 2fb783e477100ce076f6bf57e4a6f026013dc745    Documentation
100755 blob 3c0032cec592a765692234f1cba47dfdcc3a9200    GIT-VERSION-GEN
100644 blob 289b046a443c0647624607d471289b2c7dcd470b    INSTALL
100644 blob 4eb463797adc693dc168b926b6932ff53f17d0b1    Makefile
100644 blob 548142c327a6790ff8821d67c2ee1eff7a656b52    README
...

我知道最后的3位是文件模式,但是前3位是用来做什么的?我在git用户手册中找不到它。

原文
用户62695763dd4e9提问于2018-04-04 04:55

2 个回答

高票数最新
用户6269576401e72
回答于2018-04-04 13:38已采纳
得票数 0

这6位数字使用经典的UNIX符号显示文件模式。前两位数字显示文件类型,第三位是关于set-uid/set-gid/粘滞位,你知道最后三个。

以下是如何man 2 stat将其记录在我的GNU/Linux系统上:

   The following flags are defined for the st_mode field:

       S_IFMT     0170000   bit mask for the file type bit fields
       S_IFSOCK   0140000   socket
       S_IFLNK    0120000   symbolic link
       S_IFREG    0100000   regular file
       S_IFBLK    0060000   block device
       S_IFDIR    0040000   directory
       S_IFCHR    0020000   character device
       S_IFIFO    0010000   FIFO
       S_ISUID    0004000   set UID bit
       S_ISGID    0002000   set-group-ID bit (see below)
       S_ISVTX    0001000   sticky bit (see below)
       S_IRWXU    00700     mask for file owner permissions
       S_IRUSR    00400     owner has read permission
       S_IWUSR    00200     owner has write permission
       S_IXUSR    00100     owner has execute permission
       S_IRWXG    00070     mask for group permissions
       S_IRGRP    00040     group has read permission
       S_IWGRP    00020     group has write permission
       S_IXGRP    00010     group has execute permission
       S_IRWXO    00007     mask for permissions for others (not in group)
       S_IROTH    00004     others have read permission           
       S_IWOTH    00002     others have write permission
       S_IXOTH    00001     others have execute permission
用户6269576401e95
回答于2018-04-04 14:21已采纳
得票数 0

index-format.txt文件,关于模式:

32-bit mode, split into (high to low bits)

    4-bit object type
      valid values in binary are 1000 (regular file), 1010 (symbolic link)
      and 1110 (gitlink)

    3-bit unused

    9-bit unix permission. Only 0755 and 0644 are valid for regular files.
    Symbolic links and gitlinks have value 0 in this field.

此外,目录对象类型(二进制0100)和可组可写(0664权限)常规文件也被允许,如fsck.c fsck_tree方法。常规的不可执行组可写文件是一种非标准模式,在早期版本的Git中支持。

这就产生了有效的模式(二进制和八进制):

  • 0100000000000000(040000):目录
  • 1000000110100100(100644):常规的不可执行文件
  • 1000000110110100(100664):常规不可执行组可写文件
  • 1000000111101101(100755):常规可执行文件
  • 1010000000000000(120000):符号链接
  • 1110000000000000(160000):Gitlink
页面原文内容由用户62695763dd4e9、用户6269576401e72、用户6269576401e95提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接:https://stackoverflow.com/questions/-100003796复制

扫码关注云+社区

领取腾讯云代金券