LDP
/
man-pages
mirror of https://github.com/mkerrisk/man-pages
0
1
Fork 0
Code Releases Activity

mount_setattr.2: Minor clean-ups in example program 

- Change some instances of "-" to "\"
- Use C99 style (declare variables nearer use in code)
- Add a bit of white space
- Remove one 'const...const' added by Alex that caused
  compiler warnings
- Use "reverse Christmas tree" form for declarations in main()
- Other minor changes

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
This commit is contained in:
Michael Kerrisk 2021-08-09 22:56:47 +02:00
parent 8c67481023
commit f606879ab1
1 changed files with 33 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
man2/mount_setattr.2
View File

@ -629,7 +629,7 @@ More than one of
.BR MS_PRIVATE ,
or
.B MS_UNBINDABLE
was set in
was set in the
.I propagation
field of
.IR mount_attr .
@ -880,8 +880,7 @@ mount_setattr(int dfd, const char *path, unsigned int flags,
}
static inline int
open_tree(int dfd, const char *filename,
unsigned int flags)
open_tree(int dfd, const char *filename, unsigned int flags)
{
return syscall(SYS_open_tree, dfd, filename, flags);
}
@ -895,13 +894,13 @@ move_mount(int from_dfd, const char *from_pathname,
}
static const struct option longopts[] = {
{"map-mount", required_argument, NULL, 'a'},
{"map\-mount", required_argument, NULL, 'a'},
{"recursive", no_argument, NULL, 'b'},
{"read-only", no_argument, NULL, 'c'},
{"block-setid", no_argument, NULL, 'd'},
{"block-devices", no_argument, NULL, 'e'},
{"block-exec", no_argument, NULL, 'f'},
{"no-access-time", no_argument, NULL, 'g'},
{"read\-only", no_argument, NULL, 'c'},
{"block\-setid", no_argument, NULL, 'd'},
{"block\-devices", no_argument, NULL, 'e'},
{"block\-exec", no_argument, NULL, 'f'},
{"no\-access\-time", no_argument, NULL, 'g'},
{ NULL, 0, NULL, 0 },
};
@ -914,13 +913,11 @@ static const struct option longopts[] = {
int
main(int argc, char *argv[])
{
int fd_userns = \-EBADF;
int index = 0;
bool recursive = false;
struct mount_attr *attr = &(struct mount_attr){};
const char *source, *target;
int fd_tree, new_argc, ret;
const char *const *new_argv;
int fd_userns = \-EBADF;
bool recursive = false;
int index = 0;
int ret;
while ((ret = getopt_long_only(argc, argv, "",
longopts, &index)) != \-1) {
@ -934,57 +931,58 @@ main(int argc, char *argv[])
recursive = true;
break;
case 'c':
attr->attr_set |= MOUNT_ATTR_RDONLY;
attr\->attr_set |= MOUNT_ATTR_RDONLY;
break;
case 'd':
attr->attr_set |= MOUNT_ATTR_NOSUID;
attr\->attr_set |= MOUNT_ATTR_NOSUID;
break;
case 'e':
attr->attr_set |= MOUNT_ATTR_NODEV;
attr\->attr_set |= MOUNT_ATTR_NODEV;
break;
case 'f':
attr->attr_set |= MOUNT_ATTR_NOEXEC;
attr\->attr_set |= MOUNT_ATTR_NOEXEC;
break;
case 'g':
attr->attr_set |= MOUNT_ATTR_NOATIME;
attr->attr_clr |= MOUNT_ATTR__ATIME;
attr\->attr_set |= MOUNT_ATTR_NOATIME;
attr\->attr_clr |= MOUNT_ATTR__ATIME;
break;
default:
exit_log("Invalid argument specified");
}
}
new_argv = &argv[optind];
new_argc = argc \- optind;
char **new_argv = &argv[optind];
int new_argc = argc \- optind;
if (new_argc < 2)
exit_log("Missing source or target mount point\en");
source = new_argv[0];
target = new_argv[1];
fd_tree = open_tree(\-EBADF, source,
OPEN_TREE_CLONE |
OPEN_TREE_CLOEXEC |
AT_EMPTY_PATH |
(recursive ? AT_RECURSIVE : 0));
const char *source = new_argv[0];
const char *target = new_argv[1];
int fd_tree = open_tree(\-EBADF, source,
OPEN_TREE_CLONE | OPEN_TREE_CLOEXEC |
AT_EMPTY_PATH | (recursive ? AT_RECURSIVE : 0));
if (fd_tree == \-1)
exit_log("%m \- Failed to open %s\en", source);
if (fd_userns >= 0) {
attr->attr_set |= MOUNT_ATTR_IDMAP;
attr->userns_fd = fd_userns;
attr\->attr_set |= MOUNT_ATTR_IDMAP;
attr\->userns_fd = fd_userns;
}
ret = mount_setattr(fd_tree, "",
AT_EMPTY_PATH |
(recursive ? AT_RECURSIVE : 0),
AT_EMPTY_PATH | (recursive ? AT_RECURSIVE : 0),
attr, sizeof(struct mount_attr));
if (ret == \-1)
exit_log("%m - Failed to change mount attributes\en");
exit_log("%m \- Failed to change mount attributes\en");
close(fd_userns);
ret = move_mount(fd_tree, "", \-EBADF, target,
MOVE_MOUNT_F_EMPTY_PATH);
if (ret == \-1)
exit_log("%m \- Failed to attach mount to %s\en", target);
close(fd_tree);
exit(EXIT_SUCCESS);