Re: [PATCH] Avoid losing persisted clock data when exiting emac without loading org-mode

From: Kai Tetzlaff <kai.tetzlaff@gmx.de>
To: Carsten Dominik <carsten.dominik@gmail.com>
Cc: emacs-orgmode@gnu.org
Subject: Re: [PATCH] Avoid losing persisted clock data when exiting emac without loading org-mode
Date: Sat, 24 Oct 2009 20:40:36 +0200	[thread overview]
Message-ID: <4AE34A24.2030608@gmx.de> (raw)
In-Reply-To: <468CEFF9-A1C3-4888-83B6-066F2129087D@gmail.com>

[-- Attachment #1: Type: text/plain, Size: 3123 bytes --]

Carsten Dominik wrote:
> Hi Kai,
> 
> 
> On Oct 23, 2009, at 9:01 AM, Kai Tetzlaff wrote:
> 
>> Hi,
>>
>> i noticed that when using the org-mode clock persistence, the stored
>> clock data gets deleted when i start emacs and exit again without
>> turning on org-mode in between.
>>
>> When looking at org-clock-persistence-insinuate it looks like org-clock
>> load will only run after org-mode gets started whereas org-clock-save
>> will always be called when exiting emacs:
>>
>> (defun org-clock-persistence-insinuate ()
>>  "Set up hooks for clock persistence"
>>  (add-hook 'org-mode-hook 'org-clock-load)
>>  (add-hook 'kill-emacs-hook 'org-clock-save))
>>
>> Not running org-mode-hook (i.e. not starting org-mode) thus does not
>> load clock data but org-clock-save overwrites any prviously saved data
>> when exiting emacs.
>>
>> An easy fix for that would be to just add org-clock-load to e.g.
>> emacs-startup-hook. But this will only work if the code in
>> org-clock-load does not depend on any org-mode initialization code (or
>> would require loading org-mode).
>>
>> So org-clock-save should probably check if org-clock-load has been
>> running during the current emacs session (or if clock persistence was
>> just enabled) and only then save clock data when exiting emacs. I tried
>> to add this to the code in org-clock-save:
>>
>> diff --git a/lisp/org-clock.el b/lisp/org-clock.el
>> index c7ebbf8..c0fe4e6 100644
>> --- a/lisp/org-clock.el
>> +++ b/lisp/org-clock.el
>> @@ -1803,7 +1803,8 @@ This function is made for clock tables."
>>   "Persist various clock-related data to disk.
>> The details of what will be saved are regulated by the variable
>> `org-clock-persist'."
>> -  (when org-clock-persist
>> +  (when (and org-clock-persist
>> +             (or org-clock-loaded (not (file-exists-p
>> org-clock-persist-file))))
>>     (let (b)
>>       (with-current-buffer (find-file (expand-file-name
>> org-clock-persist-file))
>>     (progn
>>
>>
>> /Kai
>>
> 
> I see you point, but I am not convinced that you fix is the right one. 
> What one really wants to do is save the clock and history if and only if
> the clock has been used in the current session.  So I guess it is better
> to create a special variable org-clock-used-in-this-session which then
> will be set to t each time clock-in starts a clock somewhere.  I believe
> this would be a better insurance policy.
>
> Would you like to try your hand at a patch in this spirit?

Ok, i've attached a new path which uses the suggested approach. I wasn't
exactly sure about where to set org-clock-used-in-this-session to t.
It's now done right at the end of org-clock-in, just before running
hooks in org-clock-in-hook.

I've done a couple of (simple) tests and it works fine for me.

/Kai

> - Carsten
> 
>> _______________________________________________
>> Emacs-orgmode mailing list
>> Remember: use `Reply All' to send replies to the list.
>> Emacs-orgmode@gnu.org
>> http://lists.gnu.org/mailman/listinfo/emacs-orgmode
> 
> - Carsten
> 
> 
> 
> 



[-- Attachment #2: clock-save.patch --]
[-- Type: text/plain, Size: 1233 bytes --]

diff --git a/lisp/org-clock.el b/lisp/org-clock.el
index b1041e2..467ffc4 100644
--- a/lisp/org-clock.el
+++ b/lisp/org-clock.el
@@ -244,6 +244,7 @@ to add an effort property.")
 (defvar org-clock-heading "")
 (defvar org-clock-heading-for-remember "")
 (defvar org-clock-start-time "")
+(defvar org-clock-used-in-this-session nil)
 
 (defvar org-clock-left-over-time nil
   "If non-nil, user cancelled a clock; this is when leftover time started.")
@@ -953,6 +954,7 @@ the clocking selection, associated with the letter `d'."
 	    (setq org-clock-idle-timer
 		  (run-with-timer 60 60 'org-resolve-clocks-if-idle))
 	    (message "Clock starts at %s - %s" ts msg-extra)
+            (setq org-clock-used-in-this-session t)
 	    (run-hooks 'org-clock-in-hook)))))))
 
 (defun org-clock-mark-default-task ()
@@ -1824,7 +1826,7 @@ This function is made for clock tables."
   "Persist various clock-related data to disk.
 The details of what will be saved are regulated by the variable
 `org-clock-persist'."
-  (when org-clock-persist
+  (when (and org-clock-persist org-clock-used-in-this-session)
     (let (b)
       (with-current-buffer (find-file (expand-file-name org-clock-persist-file))
 	(progn

[-- Attachment #3: Type: text/plain, Size: 204 bytes --]

_______________________________________________
Emacs-orgmode mailing list
Remember: use `Reply All' to send replies to the list.
Emacs-orgmode@gnu.org
http://lists.gnu.org/mailman/listinfo/emacs-orgmode
