Ubuntu Manpage: abidw - serialize the ABI of an ELF file

NAME

       abidw - serialize the ABI of an ELF file

       abidw  reads  a shared library in ELF format and emits an XML representation of its ABI to
       standard output.  The emitted representation includes all the globally  defined  functions
       and  variables,  along  with a complete representation of their types.  It also includes a
       representation of the globally defined ELF symbols of the file.  The input shared  library
       must contain associated debug information in DWARF format.

       When  given  the  --linux-tree  option,  this program can also handle a Linux kernel tree.
       That is, a directory tree that contains both the vmlinux binary and Linux kernel  modules.
       It  analyses  those Linux kernel binaries and emits an XML representation of the interface
       between the kernel and its module, to standard output.  In this case, we don’t call it  an
       ABI,  but  a  KMI  (Kernel  Module  Interface).  The emitted KMI includes all the globally
       defined functions and variables, along with a complete representation of their types.  The
       input binaries must contain associated debug information in DWARF format.

INVOCATION

          abidw [options] [<path-to-elf-file>]

OPTIONS

• --help | -h

Display a short help about the command and exit.

• –version | -v

Display the version of the program and exit.

• --debug-info-dir | -d <dir-path>

In cases where the debug info for path-to-elf-file is in a separate file that is
located in a non-standard place, this tells abidw where to look for that debug info
file.

Note that dir-path must point to the root directory under which the debug information
is arranged in a tree-like manner. Under Red Hat based systems, that directory is
usually <root>/usr/lib/debug.

Note that this option is not mandatory for split debug information installed by your
system’s package manager because then abidw knows where to find it.

• --out-file <file-path>

This option instructs abidw to emit the XML representation of path-to-elf-file into
the file file-path, rather than emitting it to its standard output.

• --noout

This option instructs abidw to not emit the XML representation of the ABI. So it
only reads the ELF and debug information, builds the internal representation of the
ABI and exits. This option is usually useful for debugging purposes.

• --no-corpus-path

Do not emit the path attribute for the ABI corpus.

• --suppressions | suppr <path-to-suppression-specifications-file>

Use a suppression specification file located at
path-to-suppression-specifications-file. Note that this option can appear multiple
times on the command line. In that case, all of the provided suppression
specification files are taken into account. ABI artifacts matched by the suppression
specifications are suppressed from the output of this tool.

• --kmi-whitelist | -kaw <path-to-whitelist>

When analyzing a Linux kernel binary, this option points to the white list of names
of ELF symbols of functions and variables which ABI must be written out. That white
list is called a ” Kernel Module Interface white list”. This is because for the
Kernel, we don’t talk about the ABI; we rather talk about the interface between the
Kernel and its module. Hence the term KMI rather than ABI

Any other function or variable which ELF symbol are not present in that white list
will not be considered by the KMI writing process.

If this option is not provided – thus if no white list is provided – then the entire
KMI, that is, all publicly defined and exported functions and global variables by the
Linux Kernel binaries is emitted.

• --linux-tree | --lt

Make abidw to consider the input path as a path to a directory containing the vmlinux
binary as several kernel modules binaries. In that case, this program emits the
representation of the Kernel Module Interface (KMI) on the standard output.

Below is an example of usage of abidw on a Linux Kernel tree.

First, checkout a Linux kernel source tree and build it. Then install the kernel
modules in a directory somewhere. Copy the vmlinux binary into that directory too.
And then serialize the KMI of that kernel to disk, using abidw:

$ git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
$ cd linux && git checkout v4.5
$ make allyesconfig all
$ mkdir build-output
$ make INSTALL_MOD_PATH=./build-output modules_install
$ cp vmlinux build-output/modules/4.5.0
$ abidw --linux-tree build-output/modules/4.5.0 > build-output/linux-4.5.0.kmi

• --headers-dir | --hd <headers-directory-path-1>

Specifies where to find the public headers of the first shared library that the tool
has to consider. The tool will thus filter out types that are not defined in public
headers.

• --no-linux-kernel-mode

Without this option, if abipkgiff detects that the binaries it is looking at are
Linux Kernel binaries (either vmlinux or modules) then it only considers functions
and variables which ELF symbols are listed in the __ksymtab and __ksymtab_gpl
sections.

With this option, abipkgdiff considers the binary as a non-special ELF binary. It
thus considers functions and variables which are defined and exported in the ELF
sense.

• --check-alternate-debug-info <elf-path>

If the debug info for the file elf-path contains a reference to an alternate debug
info file, abidw checks that it can find that alternate debug info file. In that
case, it emits a meaningful success message mentioning the full path to the alternate
debug info file found. Otherwise, it emits an error code.

• --no-show-locs
In the emitted ABI representation, do not show file, line or column where ABI
artifacts are defined.

• --check-alternate-debug-info-base-name <elf-path>

Like --check-alternate-debug-info, but in the success message, only mention the base
name of the debug info file; not its full path.

• --load-all-types

By default, libabigail (and thus abidw) only loads types that are reachable from
functions and variables declarations that are publicly defined and exported by the
binary. So only those types are present in the output of abidw. This option however
makes abidw load all the types defined in the binaries, even those that are not
reachable from public declarations.

• --abidiff
Load the ABI of the ELF binary given in argument, save it in libabigail’s XML
format in a temporary file; read the ABI from the temporary XML file and compare
the ABI that has been read back against the ABI of the ELF binary given in
argument. The ABIs should compare equal. If they don’t, the program emits a
diagnostic and exits with a non-zero code.

This is a debugging and sanity check option.

• --annotate
Annotate the ABIXML output with comments above most elements. The comments are
made of the pretty-printed form types, declaration or even ELF symbols. The
purpose is to make the ABIXML output more human-readable for debugging or
documenting purposes.

• --stats

Emit statistics about various internal things.

• --verbose

Emit verbose logs about the progress of miscellaneous internal things.

NOTES

   Alternate debug info files
       As  of  the  version  4  of  the DWARF specification, Alternate debug information is a GNU
       extension to the DWARF specification.  It has however been proposed for inclusion into the
       upcoming  version  5 of the DWARF standard.  You can read more about the GNU extensions to
       the DWARF standard here.

AUTHOR

       Dodji Seketeli

COPYRIGHT

       2014-2018, Red Hat, Inc.

                                           Apr 24, 2018                                  ABIDW(1)