Re: [BUG] LaTeX preview should use a subdirectory in /tmp

[Max Nikulin <manikulin@gmail.com>]

On 25/03/2024 18:40, Ihor Radchenko wrote:
> Max Nikulin writes:
>> This feature should not write temporary files to /tmp directly
> 
> See the attached tentative patch.

Thanks for prompt reaction.

> +++ b/lisp/org.el
> @@ -16361,7 +16361,7 @@ (defun org-create-formula-image
>  	       org-format-latex-header
>  	       'snippet)))
>  	 (latex-compiler (plist-get processing-info :latex-compiler))
> -	 (tmpdir temporary-file-directory)
> +	 (tmpdir (concat temporary-file-directory "orgtex/"))
>  	 (texfilebase (make-temp-name
>  		       (expand-file-name "orgtex" tmpdir)))

Since directory name already contains "org", it may be shortened to just 
"tex"

>  	 (texfile (concat texfilebase ".tex"))

I would use `make-temp-file' to create TEXFILE and would derive 
TEXFILEBASE from it. In general it is safer.

To create directory I expect a call of a function similar to the 
following one. Perhaps it exists already somewhere.

(defun org-ensure-tmp-dir (dir-symbol prefix)
   (let ((dir (symbol-value dir-symbol)))
     ;; Temporary directory has not been cleaned.
     (or (and dir (file-directory-p dir) dir)
	(setf (symbol-value dir-symbol)
	      (make-temp-file (or prefix "orgtmp-") 'dir)))))

(defvar org-tex-tmpdir nil)

Usage example: (org-ensure-tmp-dir 'org-tex-tmpdir "orgtex-")

Fixed directory name is not friendly for multi-user systems and 
predictable name in /tmp might be a source of security issues.