[2828] in Release_Engineering
Re: Problem with setpag and login/xlogin
daemon@ATHENA.MIT.EDU (Richard Basch)
Sun May 17 21:18:11 1992
Date: Sun, 17 May 92 21:17:36 -0400
To: epeisach@MIT.EDU
Cc: builder@MIT.EDU, rel-eng@MIT.EDU
In-Reply-To: Ezra Peisach's message of Sun, 17 May 92 11:35:06 -0400,
From: "Richard Basch" <basch@MIT.EDU>
This may be a solution...
Someone should definitely check it over...
Please note that I did not trust some of the previous tests in some
cases; I felt that it may be possible for certain conditions to arise
where various errors might return "local" rather than remote. I was
able to demonstrate that open(dir,...) would fail on NFS filesystems if
permission did not exist and it was still mounted, so I included the
device check whenever possible.
-Richard
*** /tmp/,RCSt1UloAK1 Sun May 17 21:16:22 1992
--- verify.c Sun May 17 21:16:18 1992
***************
*** 879,926 ****
/* Function Name: IsRemoteDir
! * Description: Stolen form athena's version of /bin/login
! * returns true of this is an NFS directory.
! * Arguments: dname - name of the directory.
* Returns: true or false to the question (is remote dir).
*
! * The following lines rely on the behavior of Sun's NFS (present in
! * 3.0 and 3.2) which causes a read on an NFS directory (actually any
! * non-reg file) to return -1, and AFS which also returns a -1 on
! * read (although with a different errno). This is a fast, cheap
! * way to discover whether a user's homedir is a remote filesystem.
! * Naturally, if the NFS and/or AFS semantics change, this must also change.
*/
IsRemoteDir(dir)
char *dir;
{
! #if !defined(_AIX)
int f;
char c;
struct stat stbuf;
! if (lstat(dir, &stbuf))
! return(FALSE);
! if (!(stbuf.st_mode & S_IFDIR))
return(TRUE);
! if ((f = open(dir, O_RDONLY, 0)) < 0)
! return(FALSE);
!
! if (read(f, &c, 1) < 0) {
close(f);
return(TRUE);
}
-
close(f);
return(FALSE);
- #else /* AIX */
- struct stat stbuf;
-
- if (statx(dir, &stbuf, 0, STX_NORMAL))
- return(FALSE);
- return((stbuf.st_flag & FS_REMOTE) ? TRUE : FALSE);
#endif
}
--- 879,946 ----
/* Function Name: IsRemoteDir
! * Arguments: dir - name of the directory.
* Returns: true or false to the question (is remote dir).
+ * false may also indicate that no directory exists.
*
! * If we cannot stat/open the directory, and the error was not ENOENT,
! * we will assume the directory is remote. Getting information about
! * a directory may not be possible if the pre-requisite authentication
! * has not yet been performed.
! *
! * With AIX, we only need to check the FS_REMOTE flag.
! *
! * Under other systems, we rely on the behavior of Sun's NFS
! * which causes a read on an NFS directory (or any non-regular file)
! * to return -1. However, because this doesn't work with AFS, we
! * also check the device number.
! *
! * If the semantics change, this function has to be revised!!!
*/
IsRemoteDir(dir)
char *dir;
{
! #if defined(_AIX)
! #define REMOTEDONE
! struct stat stbuf;
!
! if (statx(dir, &stbuf, 0, STX_NORMAL))
! return((errno==ENOENT) ? FALSE : TRUE);
! return((stbuf.st_flag & FS_REMOTE) ? TRUE : FALSE);
! #endif
!
! #if !defined(REMOTEDONE)
!
! #if (defined(vax) && !defined(ultrix)) || defined(ibm032)
! #define CHECK_NFSDEV
! #endif
!
int f;
char c;
struct stat stbuf;
! if (stat(dir, &stbuf))
! return((errno==ENOENT) ? FALSE : TRUE);
!
! switch(stbuf.st_rdev) {
! case 0x0001: /* AFS */
! #ifdef CHECK_NFSDEV
! case 0xff00: /* NFS */
! #endif
return(TRUE);
+ break;
+ }
! #ifndef CHECK_NFSDEV
! if ((f = open(dir, O_RDONLY, 0)) < 0 ||
! read(f, &c, 1) < 0) {
close(f);
return(TRUE);
}
close(f);
+ #endif
return(FALSE);
#endif
}
