fchmod, fchown, lchown.
* winsup/cygwin/syscalls.cc (chown_worker): Use previous
uid/gid if new uid/gid is -1.
New static function with chown functionality.
(chown): Call chown_worker with SYMLINK_FOLLOW.
(fchown): New function. Call chown_worker with SYMLINK_FOLLOW.
(lchown): New function. Call chown_worker with SYMLINK_IGNORE.
* cygwin.din: Add symbols for fchown, lchown.
* path.cc (symlink): Call `set_file_attribute()' and
`SetFileAttributeA()' instead of `chmod()' to set
uid/gid correct.
* path.h: Make PATH_SYMLINK an alias for MOUNT_SYMLINK.
* syscalls.cc (stat_worker): Use extension search mechanism in path_conv to
look for .exe rather than trying to special case it here.
* mount.h: Make MOUNT_SYMLINK a real option.
(get_nt_attribute): Returns uid and gid additionally. Removed call
to set_process_privileges().
(get_file_attribute): Returns uid and gid additionally. Don't
call ntea if ntsec is ON.
(set_nt_attribute): Removed call to set_process_privileges().
Don't call ntea if ntsec is ON.
(acl): Removed call to set_process_privileges().
* dcrt0.cc (dll_crt0_1): Calls set_process_privileges() now.
* winsup.h: New prototype for set_process_privileges(),
changed prototype for get_file_attribute().
* fhandler.cc (get_file_owner): Discarded.
(get_file_group): Ditto.
(fhandler_disk_file::fstat): Discard calls to get_file_owner() and
get_file_group().
* path.cc (path_conv::path_conv): Added debugging output for result
of GetVolumeInformation().
(mount_info::conv_to_win32_path): Call backslashify() with pathbuf
instead of src_path.
* syscalls.cc (chown): Reformatted.
(chmod): Replace get_file_owner() and get_file_group() calls
by a call to get_file_attribute(). Discard local variable has_acls.
Slightly reformatted.
(stat_worker): Replaced idiot's (it's me) root dir check by call
to rootdir(). Don't call num_entries() on remote drives.
Discard local variable has_acls.
