K 10
svn:author
V 3
mjg
K 8
svn:date
V 27
2012-07-18T04:52:37.698597Z
K 7
svn:log
V 629
MFC r238220, r238272:

Unbreak handling of descriptors opened with O_EXEC by fexecve(2).

While here return EBADF for descriptors opened for writing (previously it was ETXTBSY).

Add fgetvp_exec function which performs appropriate checks.

==

Follow-up commit to r238220:

Pass only FEXEC (instead of FREAD|FEXEC) in fgetvp_exec. _fget has to check for
!FWRITE anyway and may as well know about FREAD.

Make _fget code a bit more readable by converting permission checking from if()
to switch(). Assert that correct permission flags are passed.

PR:		kern/169651
In collaboration with:	kib
Approved by:	re (hrs), trasz (mentor)

END