Re: [Elftoolchain-developers] Support for "in-place" updates to ELF objects has been added to libelf

[Eric S. <sch...@gm...>]

Joseph Koshy <jk...@us...> writes:

> e.s> Would it be possible to share a simple C script which opens, edits and
> e.s> then writes out a modified elf file using libelf?
>
> There are a few such examples in libelf's test suite; please look for
> the constant "ELF_C_RDWR" in:
>
>     http://sourceforge.net/apps/trac/elftoolchain/browser/trunk/test/libelf/tset/elf_update/update.m4
>

Thanks for the pointer.  Attached is my attempt to re-write one of the
test cases into an external C file to allow extending a data section in
an existing elf file.  The resulting script fails with the following...

  $ ./extend-a-section hello
  fstat() failed: "Bad address".
  Size error: expected=118, elf_update()=6536

I imagine that I broke something while replacing the TC_* macros with C
code.  I apologize for asking such a simple question, but would you mind
taking a look to see if the error is obvious to you.

Thanks -- Eric