[fpc-devel] SqlDB + Firebird application doesn't run on new Ubuntu installation

[Michael Van Canneyt]

On Thu, 26 Nov 2009, Graeme Geldenhuys wrote:

> Hi,
>
> I previously raised this issue, but nothing came from that message thread.
>
>  http://lists.freepascal.org/lists/fpc-devel/2009-August/017296.html
>
> To recap, here is the problem...
>
> I noticed that on newer Ubuntu Linux systems that the name of the
> Firebird shared library has changed for v2.x versions of Firebird
> Database Server. Apparently this change in not only limited to Ubuntu,
> but many other Linux distro's too.
>
> ----------------------------------
> $ ls -l /usr/lib/libfbcl*
> 2009-08-24 12:06 /usr/lib/libfbclient.so.2 -> libfbclient.so.2.1.1
> 2008-11-19 20:09 /usr/lib/libfbclient.so.2.1.1
> ----------------------------------
>
>
> The SqlDB + Firebird code only looks for 'libgds.so' and
> 'libfbclient.so' giving the following error at runtime...
>
> Without the un-versioned symbolic link, SqlDB + Firebird applications
> will not run, even if the user installed the 'libfbclient2' package.
>
>
> I was told that only development packages include the un-versioned
> symbolic link, because only the linker (and other development tools)
> should be the only apps that use that unversioned library.
> Applications are supposed to use the versioned libraries instead. See
> Luca's reply for the full explanation.
>
> http://lists.freepascal.org/lists/fpc-devel/2009-August/017300.html
>
>
> The work around on the client PC is simple, but I do not think this is
> the ideal solution - forcing the user to manually create a
> libfbclient.so symbolic link to the versioned on. And to do that, they
> must have root privileges!
>
>
> Possible solutions:
> -------------------
> 1) Change SqlDB + Firebird code to look for 'libfbclient.so.2' by
> default. After all, version 2 of Firebird has been out for years.
>
> 2) Add a extra check in InitialiseIBase60() [ibase60.inc] to check for
> versioned and un-versioned client libraries. The thirdparty FBLib
> package used to do this and it worked fine. It doesn't need to check
> minor versions, only major versions - starting at newest and working
> back to oldest versions. eg:
>
>   if found libfbclient.so.2 then  // latest major version of Firebird
>      ...
>   else if found libfbclient.so.1 then // previous major version
>      ...
>   else if found libfbclient.so then  // finally the unversioned one
>      ...
>
> 3) Somehow allow the developer to specify via a SqlDB property which
> version the initialization code should look for. After all, the
> developer knows which version of the database server they developed
> for.
>
>
> I don't mind creating a patch for option 2 above. Would such a patch
> be accepted though? It shouldn't break anything - in contrary, it will
> only improve user experience and less application crashes in deployed
> software.

Please create a patch.

Note that it is already possible to tell initialiseIBase60 which
library it should load, so it's possible to do a workaround.

Michael.