lkml.org 
[lkml]   [2017]   [Nov]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    From
    SubjectRe: [PATCH] vfs: Add PERM_* symbolic helpers for common file mode/permissions
    Date
    Ingo Molnar <mingo@kernel.org> writes:
    ...
    > Index: tip/include/linux/stat.h
    > ===================================================================
    > --- tip.orig/include/linux/stat.h
    > +++ tip/include/linux/stat.h
    > @@ -6,6 +6,34 @@
    > #include <asm/stat.h>
    > #include <uapi/linux/stat.h>
    >
    > +/*
    > + * Human readable symbolic definitions for common
    > + * file permissions:
    > + */
    > +#define PERM_r________ 0400
    > +#define PERM_r__r_____ 0440
    > +#define PERM_r__r__r__ 0444
    > +
    > +#define PERM_rw_______ 0600
    > +#define PERM_rw_r_____ 0640
    > +#define PERM_rw_r__r__ 0644
    > +#define PERM_rw_rw_r__ 0664
    > +#define PERM_rw_rw_rw_ 0666
    > +
    > +#define PERM__w_______ 0200
    > +#define PERM__w__w____ 0220
    > +#define PERM__w__w__w_ 0222
    > +
    > +#define PERM_r_x______ 0500
    > +#define PERM_r_xr_x___ 0550
    > +#define PERM_r_xr_xr_x 0555
    > +
    > +#define PERM_rwx______ 0700
    > +#define PERM_rwxr_x___ 0750
    > +#define PERM_rwxr_xr_x 0755
    > +#define PERM_rwxrwxr_x 0775
    > +#define PERM_rwxrwxrwx 0777

    I see what you're trying to do with all the explicit underscores, but it
    does make them look kinda ugly.

    What if you just used underscores to separate the user/group/other, and
    the unset permission bits are just omitted.

    Then the two most common cases would be:

    PERM_rw_r_r
    PERM_r_r_r

    Both of those read nicely I think. ie. the first is "perm read write,
    read, read".

    Full set would be:

    #define PERM_r 0400
    #define PERM_r_r 0440
    #define PERM_r_r_r 0444

    #define PERM_rw 0600
    #define PERM_rw_r 0640
    #define PERM_rw_r_r 0644
    #define PERM_rw_rw_r 0664
    #define PERM_rw_rw_rw 0666

    #define PERM_w 0200
    #define PERM_w_w 0220
    #define PERM_w_w_w 0222

    #define PERM_rx 0500
    #define PERM_rx_rx 0550
    #define PERM_rx_rx_rx 0555

    #define PERM_rwx 0700
    #define PERM_rwx_rx 0750
    #define PERM_rwx_rx_rx 0755
    #define PERM_rwx_rwx_rx 0775
    #define PERM_rwx_rwx_rwx 0777


    cheers

    \
     
     \ /
      Last update: 2017-11-29 09:53    [W:2.879 / U:0.112 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site