Re: {PATCH] minor gpg.el fix for MS Windows

[Dmitry Bely <dbely@mail.ru>]

Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Grossjohann) writes:

>>  (defcustom gpg-temp-directory 
>> -  (expand-file-name "~/tmp")
>> +  (if (memq system-type '(windows-nt cygwin32 win32 w32 mswindows))
>> +      (temp-directory)
>> +    (expand-file-name "~/tmp"))
>
> I use the following code to get a temp directory in Tramp:
>
> (defun tramp-temporary-file-directory ()
>   "Return name of directory for temporary files (compat function).
> For Emacs, this is the variable `temporary-file-directory', for XEmacs
> this is the function `temp-directory'."

I did not know that "temp-directory" function does not exist in
Emacs. Sorry.

>   (cond ((boundp 'temporary-file-directory)
>          (symbol-value 'temporary-file-directory))
>         ((fboundp 'temp-directory)
>          (funcall (symbol-function 'temp-directory))) ;pacify byte-compiler
>         ((let ((d (getenv "TEMP"))) (and d (file-directory-p d)))
>          (file-name-as-directory (getenv "TEMP")))
>         ((let ((d (getenv "TMP"))) (and d (file-directory-p d)))
>          (file-name-as-directory (getenv "TMP")))
>         ((let ((d (getenv "TMPDIR"))) (and d (file-directory-p d)))
>          (file-name-as-directory (getenv "TMPDIR")))
>         ((file-exists-p "c:/temp") (file-name-as-directory "c:/temp"))
>         (t (message (concat "Neither `temporary-file-directory' nor "
>                             "`temp-directory' is defined -- using /tmp."))
>            (file-name-as-directory "/tmp"))))
>
> Opinions?

For me it's basically OK but

1. I don't know about Emacs, but in XEmacs (temp-directory) does all this
job itself.
2. For the crypto stuff (gpg.el) such general purpose function is not very
good: for Unix it returns "/tmp" directory by default, which is world
readable. Just imagine what can happen with your top secret mail :-) I
think what's why Florian uses "~/tmp" instead. On the other side, it's OK
for WinNT, because its TEMP environment variable points to the directory
that is unique for every user and is not readable by anybody else. So
something like

(defcustom gpg-temp-directory 
  (if (memq system-type '(windows-nt cygwin32 win32 w32 mswindows))
      (something-like-your-function-above)
    (expand-file-name "~/tmp"))
  ...

IMHO would make sense.

Hope to hear from you soon,
Dmitry