On Thu, 2009-11-19 at 13:31 +0100, Kern Sibbald wrote: > Hello Marco, > > > Hi, > > > > I have made the first small steps to be able to be able to use different > > database backends in the same compiled binary. Just to be sure no > > one else is working on the same code I just post here that I started > > with no idea when it will be ready but as it seems I just need to > > move some code around and write some glue code that select the right > > database functions based on the database type selected. For now we > > will probably start with a runtime selection of the database which > > will load the correct shared object (e.g. I'm not going to put much > > effort in the static versions of the dird those will be limited to > > only one backend.) > > Yes, much of the work was done by two things: > 1. You adding shared objects I think we could have done shared objects for the database without the shared libs but yes it makes things a lot easier now we have libtool :-)
> 2. Implementation of the ODBI driver where all SQL engine dependent code > was put on a variable so that Bacula could index to the right SQL for the > db engine loaded. > I have seen that it looks very nifty and I think it will help a lot. > As you have noted, about the only thing to do is: > 1. Allow multiple engines to be defined. > 2. Build a separate shared object (dll) for each one ensuring that > 3. Each has a different name. > 4. Dynamically load the appropriate one at runtime. > I am also going to rename some functions in some function as they give name conflicts (e.g. exist multiple times) I probably prefix them with something unique. > Be aware that some changes to the Windows code will also be necessary. > As you know Windows is not my primary concern (sorry :-)) but I will make sure not to break it by making sure for now that it will work as things work now just like with static compiled stuff. > I would very strongly recommend you to see if you can use the code that > loads the plugins. Hopefully it can be adapted to load any Bacula shared > object. It already has everything you need to find and load the sh or > dll. > > I will have a look, I'm currently in the phase of making a design in my head and doing some preliminary work to seperate the stuff and create the first changes to the Makefile, as that will need quite some surgery also for the install target as it now only installs scripts for one db and that will change. > > > > > As I think it will be quite an effort and we are doing a feature freeze > > soon don't expect this to be in 3.2 but maybe somewhere early next year > > it will go into the 3.3.x GIT branch. Also no promise as to when it will > > be done. I have a rather heavy job next to my work on Bacula so its get > > the attention I can spend on it. I still need to make a good design in > > my mind but on a first read of the code I think I will drop the defines > > currently in cats.h and write glue code for those functions there. > > Yes, this is something that for the moment we will want to put into a > branch and then merge with the master right after the release of 3.2 > I branched already in my local GIT repo, when it looks like something I will publish it, and You and Eric can already peek :-) Not much to see there yet however. > > > > Are we ok that we use dlsym and dlopen etc interfaces ? That way I can > > reuse some of my knowledge I have on programming that interface years > > ago on some other code I have written way back. > > Yes, but please see about the possibility of using the existing code to > load plugins. > Sure I will have a look, maybe merge that code with some code I wrote years ago. Its not like the whole dlsym and dlopen stuff is rocket science. > > > > So once again don't hold your breath, but please speak up if you already > > started a similar effort and already made it trough a long way. > > Duplicating the same effort would be something of a waste. > > > At the moment no one is working on this, so it is all yours :-) > Ok I just hate it when you start on something and then someone says oh we already have that or someone else is working on exactly that. > Many thanks. No problem I think this is an interesting add on and gives me something to do next to my day-to-day work that is kind of tedious at the moment so working in Bacula gives me back a good feeling that things are appreciated. Marco ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Bacula-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/bacula-devel
