GNOMEish way of doing dbus :)

[Fridrich Strba]

On Wed, 2010-04-14 at 12:56 +0200, Ralf Habacker wrote: 
> on KDE windows the following directories are searched by default
> 
>     1. default service dir: <dbus-install-root>/data/dbus-1/services
>     2. default service dir: <CommonProgramFiles>/dbus-1/services
> 
> where <dbus-install-root> will be detected on runtime from the location 
> of the shared dbus library according to one of these possible path layouts.
> 
>     <dbus-install-root>/bin/[lib]dbus-1.dll
>     <dbus-install-root>/[lib]dbus-1.dll   
> 
> and <CommonProgramFiles> is the content of the environment variable 
> "CommonProgramFiles".
> According to your above statement it looks to me, that KDE uses the same 
> assumption and there is no need to change anything.

OK, will have to look again. Maybe some cmake vs. autofoo differences.
BTW, what is the 

> How does an exec path in a service file looks in gnome/windows - like 
> the one below ?
> 
> exec=DBUS_PREFIX/bin/test-service.exe

yeah or maybe 
exec=DBUS_PREFIX/libexec/some-service-without-extension

But it is the same scenario.

> Services located in 1. (which are from the dbus installation or if dbus 
> is part of a bigger package from that package) are able to use relativ 
> pathes without any relation to the installation prefix.
> 
> <dbus-install-root>/data/dbus-1/services/test.service
> exec=../../../bin/test-service.exe
> 
> service files using case 2 will not work without any relation to the 
> installation prefix.
> 
> <CommonProgramFiles>/dbus-1/services/test.service
> exec=../../<dbus-install-root>/bin/test-service.exe
> 
> - having a string like DBUS_PREFIX as root will solve this problems.
> 
> exec=DBUS_PREFIX/bin/test-service.exe
> 
> On the other side this raises the question to which dbus installation 
> root DBUS_PREFIX  will be expanded, when multiple dbus installations are 
> available.
> 
> I guess that services installed in <CommonProgramFiles>/dbus-1/services 
> are services from 3rd party applications using dbus as standalone 
> package. Because those packages are installed somewhere in 
> %PROGRAMFILES%/<package-install-root> they have to use an absolute path 
> to the service executable. The conclusion is that there is no need for a 
> DBUS_PREFIX here or are I'm completly wrong ?

OK, I relocate the prefix only if the string starts by that prefix, so
if the full path is not having the configure time prefix as it's
beginning, I will not touch it and dbus will get it unmodified.

The problem with the relative paths is that they would have to be
computed on configure time. Because a user can simply define
--with-libexecdir=<prefix>/lib/<package_name> and assuming
--with-libexecdir=<prefix>/libexec would not work.

OTOH, I also understand the danger of relocating stuff that should not
be relocated. That is why the relocation is done only under restrictive
conditions.

Cheers

Fridrich