[O] [babel] VC-Log does not run correctly

[Sebastien Vauban]

#+TITLE:     Last VC Log
#+AUTHOR:    Seb Vauban
#+DATE:      2011-09-08
#+LANGUAGE:  en
#+OPTIONS:   num:nil toc:nil

* Abstract

I'm trying to get, from the VC backend (currently SVN in my case), the name
and date of the last committer. Eventually, as well the last log message.

Therefore, I try to use the =vc-log= function in the Library of Babel, copied
back in this buffer, for the sake of simplicity.

When calling =C-c C-e b= on this buffer, I get asked by Emacs:

    "Buffer has a running process; kill it? (yes or no)"

- If I don't say anything, the export process is just hanging in the blue...

- If I say yes, the export process really begins, but there is no vc log
  inserted where I expect it.

- Exactly the same (as if I say yes) happens if I say no: export goes on, but
  no vc log!

What could go wrong here?

* Org Source

#+source: vc-log
#+headers: :var limit=-1
#+headers: :var buf=(buffer-name (current-buffer))
#+begin_src emacs-lisp :exports none
  ;; Most of this code is copied from vc.el vc-print-log
  (require 'vc)
  (when (vc-find-backend-function
         (vc-backend (buffer-file-name (get-buffer buf))) 'print-log)
    (let ((limit -1)
          (vc-fileset nil)
          (backend nil)
          (files nil))
      (with-current-buffer (get-buffer buf)
        (setq vc-fileset (vc-deduce-fileset t)) ; FIXME: Why t? --Stef
        (setq backend (car vc-fileset))
        (setq files (cadr vc-fileset)))
      (with-temp-buffer 
        (let ((status (vc-call-backend
                       backend 'print-log files (current-buffer))))
          (when (and (processp status)   ; Make sure status is a process
                     (= 0 (process-exit-status status))) ; which has not 
terminated
            (while (not (eq 'exit (process-status status)))
              (sit-for 1 t)))
          (buffer-string)))))
#+end_src

Last edited by XXX on XXX

#+call: vc-log()

* HTML Result

#+begin_src html
Last VC Log
Org Source

Last edited by XXX on XXX

Working file: c:/home/sva/ecm.org

Date: 2011-09-08

Author: Seb Vauban
Validate XHTML 1.0
#+end_src

As you can see, there is no vc log at all, well the header of the vc log
buffer:

    "Working file: c:/home/sva/ecm.org"

* Messages buffer

#+begin_src text
Export buffer: 
Exporting...
Running svn status -v ecm.html in foreground...
Running svn status -v ecm.html...OK = 0
Position saved to mark ring, go back with M-x org-mark-ring-goto.
(info) +-> Requiring `help-fns'... already loaded [6 times]
executing Emacs-Lisp code block (vc-log)...

(buf (quote "ecm.org"))

(limit (quote -1))

Running svn log -rHEAD:0 ecm.org in background... done
"Working file: c:/home/sva/ecm.org
"
(info) +-> Requiring `help-fns'... already loaded
executing Emacs-Lisp code block...

(results (quote "Working file: c:/home/sva/ecm.org
"))

Code block evaluation complete.
org-babel-exp processing...
org-babel-exp processing...
Exporting...
Saving file c:/home/sva/ecm.html...
Wrote c:/home/sva/ecm.html
Running svn status -v ecm.html in foreground...
Running svn status -v ecm.html...OK = 0
Exporting... done
#+end_src

Any idea on how to help me going further with this?

Best regards,
  Seb

-- 
Sebastien Vauban