bool emitElfUtils::updateRelocation(Symtab *obj, relocationEntry &rel, int library_adjust) {
// Currently, only verified on x86 and x86_64 -- this may work on other architectures
Region *targetRegion = obj->findEnclosingRegion(rel.rel_addr());
if( NULL == targetRegion ) {
rewrite_printf("Failed to find enclosing Region for relocation");
return false;
}
// Used to update a Region
/*switch( rel.getCategory( obj->getAddressWidth() ))
{
case relocationEntry::relative:
rel.setAddend(rel.addend() + library_adjust);
break;
case relocationEntry::jump_slot:
if( !adjustValInRegion(targetRegion,
rel.rel_addr() - targetRegion->getDiskOffset(),
addressWidth, library_adjust) )
{
rewrite_printf("Failed to update relocation\n");
return false;
}
break;
case relocationEntry::absolute:
break;
default:
fprintf(stderr, "Undefined relocation category.\n");
assert(0);
}*/
unsigned addressWidth = obj->getAddressWidth();
if( addressWidth == 8 ) {
switch(rel.getRelType()) {
case R_AARCH64_RELATIVE:
rel.setAddend(rel.addend() + library_adjust);
break;
case R_AARCH64_JUMP_SLOT:
if( !adjustValInRegion(targetRegion,
rel.rel_addr() - targetRegion->getDiskOffset(),
addressWidth, library_adjust) )
{
rewrite_printf("Failed to update relocation\n");
return false;
}
break;
case R_AARCH64_GLOB_DAT:
break;
default:
//fprintf(stderr, "Unimplemented relType for architecture: %d\n", rel.getRelType());
//assert(0);
break;
}
}
// XXX The GOT also holds a pointer to the DYNAMIC segment -- this is currently not
// updated. However, this appears to be unneeded for regular shared libraries.
// From the SYS V ABI x86 supplement
// "The table's entry zero is reserved to hold the address of the dynamic structure,
// referenced with the symbol _DYNAMIC. This allows a program, such as the
// dynamic linker, to find its own dynamic structure without having yet processed
// its relocation entries. This is especially important for the dynamic linker, because
// it must initialize itself without relying on other programs to relocate its memory
// image."
// In order to implement this, would have determine the final address of a new .dynamic
// section before outputting the patched GOT data -- this will require some refactoring.
//rewrite_printf("WARNING: updateRelocation is not implemented on this architecture\n");
//(void) obj; (void) rel; (void) library_adjust; //silence warnings
return true;
}
