Re: [Elftoolchain-developers] A truly read-write elf?

[Joseph K. <jk...@us...>]

> I am trying to get elftoolchain to generate a read-write elf that
> actually works, however, everytime I call update(ELF_C_WRITE),
> almost all of the data structures get destroyed.

The internal data structures associated with an ELF object do get
freed on successful completion of an elf_update(ELF_C_WRITE)
operation.  Applications are required to retrieve this information
afresh from the ELF descriptor after calling elf_update(ELF_C_WRITE).

> See elf_update.cpp:_libelf_update_elf.

What is "elf_update.cpp" here?  If there was an attachment with example
code, it does not seem to have come through.

> Now, since I have a new raw elf data, how do I reconstruct the in
> memory elf data structure from the rawelf file that was returned in
> __libelf_update_elf?

I'm not sure I understand the question.

After a call to elf_update(3), you should be able to query the new
contents of the ELF object using the functions in GELF(3)/ELF(3)
API (i.e., gelf_getehdr, gelf_getphdr, elf_getscn, etc.), just as you
would for a fresh ELF descriptor.

Hope this helps.

Regards,
Koshy