Re: Baked-in paths

[John Calcote]

Hi Reuben,

On 3/14/2010 4:29 PM, Reuben Thomas wrote:
> I imagine this question has been asked before, but searching the
> archives, the net and the manual didn't help me with the following:
>
> I have a C program which loads some scripts at runtime. These are
> stored in datadir (e.g. /usr/local/share/prog). But I also want to be
> able to run the program from its build directory.
>
> At the moment I bake in the relevant path; I imagine that for "make
> install" I have to rebuild the binary, baking in the installation
> path, having baked the build directory path in a normal "make".
>
> Is there a recommended way to deal with this situation?
>
>    

The software packages I've worked on have all been complex enough to 
warrant a configuration file in the system config directory (/etc, 
whatever), which is locked down by virtue of its location. Since only 
the administrator can change the contents of a file in $(sysconfdir), 
it's not a security issue.

But what this does allow me to do is generate an installed configuration 
file with reasonable default paths derived from $(prefix) variables. At 
the same time, I bake default paths into the application, which are also 
derived from $(prefix) variables and passed on the compiler command 
line. This allows me to run without a config file, as long as the app is 
properly installed. Finally, the key benefit is that I can run my 
program in test mode by supplying an appropriate config file on the 
command line (./program -c testconfig.ini).

I love the flexibility this system provides, and I don't see any 
security issues with it, unless your program must be run as root in 
order to do what it needs to do. In that case, it's not safe to execute 
it during make check anyway. But it can be executed during make 
installcheck.

John