using BFD to load and reloc a simple file

[Daniel Jacobowitz]

On Thu, Mar 02, 2006 at 01:15:18PM -0800, thockin@hockin.org wrote:
> I am trying to load and relocate a simple ELF executable.  It's entirely
> self contained, but needs to be loadable at an arbitrary 32 bit address.
> 
> I'm trying to use libbfd for this, but I am having trouble.  The load goes
> fine, and it copies the ELF data into memory where I tell it to.  Very
> nice and very easy.  When I call perform_relocation(), though, it goes
> haywire.

That's because this is a routine for the linker, not a routine for
in-place relocation.

> bfd_perform_relocation() eventually does:
> 	reloc_target_output_section = symbol->section->output_section;
> 
> The problem is that output_section is always NULL.  I don't want to output
> a BFD, I want to relocate it in memory.

You might be able to set the section to point at itself.  However, I'm
not sure if bfd_perform_relocation even does the operation you want it
to.

-- 
Daniel Jacobowitz
CodeSourcery