ABIGAIL stands for the Application Binary Interface Generic
Analysis and Instrumentation Library.
It's a framework which aims at helping developers and software
distributors to spot some ABI-related issues like interface
incompatibility in ELF shared libraries by performing a static
analysis of the ELF binaries at hand.
The type of interface incompatibilities that Abigail focuses on
is related to changes on the exported ELF functions and variables
symbols, as well as layout and size changes of data types of the
functions and variables exported by shared libraries.
In other words, if the return type of a function exported by a
shared library changes in an incompatible way from one version of
a given shared library to another, we want Abigail to help people
catch that.
In more concrete terms, the Abigail framwork provides a shared
library named libabigail which exposes an API to parse a shared
library in ELF format (accompanied with its associated debug
information in DWARF format) build an internal representation of
all the functions and variables it exports, along with their
types. Libabigail also builds an internal representation of the
ELF symbols of these functions and variables. That information
about these exported functions and variables is roughly what we
consider as being the ABI of the shared library, at least, in the
scope of Libabigail.
Aside of this internal representation, libabigail provides
facilities to perform deep comparisons of two ABIs. That is, it
can compare the types of two sets of functions or variables and
represents the result in a way that allows it to emit textual
reports about the differences.
This allows us to write tools like abidiff that can compare the
ABI of two shared libraries and represent the result in a
meaningful enough way to help us spot ABI incompatibilities.
There are several other tools that are built using the Abigail
framwork.
