libguestfs/docs/guestfs-building.pod

=head1 NAME

guestfs-building - How to build libguestfs from source

=head1 DESCRIPTION

This manual page describes how to build libguestfs from source.

The main steps are:

=over 4

=item *

Install the requirements.

=item *

Build, either from the git repository or from a tarball.

=item *

Run the tests.

=item *

Run the tools from the source directory, or install.

=back

=head1 REQUIREMENTS

=head2 Short cut for Fedora or Red Hat Enterprise Linux (RHEL) users

On Fedora, use L<dnf(8)> to install all the requirements:

 dnf builddep libguestfs

On systems still using L<yum(8)>, do:

 yum-builddep libguestfs

=head2 Short cut for Debian or Ubuntu users

Use APT to install all the requirements:

 apt-get build-dep libguestfs

If that command doesn't work, take a look at the Debian source package
L<http://packages.debian.org/source/libguestfs>, at the list of
C<build-depends> and C<build-depends-indep>, and install everything
listed there.

=head2 Full list of requirements

=over 4

=item F<appliance/packagelist.in>

Install as many package names found in this file as possible.  (It is
not strictly required to install all of them).

=item qemu E<ge> 1.3.0

I<Required>.

=item qemu-img E<ge> 1.3.0

I<Required>.  Virt-p2v and virt-v2v requires qemu-img E<ge> 2.2.0.

=item kernel E<ge> 2.6.34

I<Required>.  The following features must be enabled:
C<virtio-pci>, C<virtio-serial>, C<virtio-block>, C<virtio-net>.

=item supermin E<ge> 5.1.0

I<Required>.  For alternatives, see L</USING A PREBUILT BINARY APPLIANCE>
below.

=item glibc

I<Required>.  We use various glibc-isms, and glibc also provides XDR
libraries and the C<rpcgen> tool.

=item Gcc or Clang

I<Required>.  We use C<__attribute__((cleanup))> which is a GCC
extension also supported by Clang.

=item Perl

I<Required>.  Various build steps and tests are written in Perl.  Perl
is not needed at runtime except if you need to run a small number of
virt tools which are still written in Perl.

=item Perl C<Pod::Man>

=item Perl C<Pod::Simple>

I<Required>.  Part of Perl core.

=item OCaml E<ge> 3.11

=item OCaml findlib

I<Required> if compiling from git.
Optional (but recommended) if compiling from tarball.

=item autoconf

=item automake

I<Required> if compiling from git.
Optional if compiling from tarball.

=item cpio

I<Required>.

=item gperf

I<Required>.

=item flex

=item bison

I<Required>.

=item Perl-compatible Regular Expressions (PCRE) library

I<Required>.

=item genisoimage

I<Required>.

=item libxml2

I<Required>.

=item ncurses

I<Required>.

=item augeas E<ge> 1.0.0

I<Required>.

=item xz

I<Required>.

=item yajl E<ge> 2.0.4

I<Required>.

=item po4a

I<Required> if compiling from git.
Optional if compiling from tarball.

=item hivex E<ge> 1.2.7

I<Required> if compiling from git, and highly recommended otherwise.
Various core features will be disabled if hivex is not available.

=item libmagic

Optional.  This is the library used by the L<file(1)> command.

=item libvirt E<ge> 0.10.2

Optional.  Always use the latest possible version of libvirt.

=item xmllint

Optional.  Used only for tests.

=item libconfig

Optional.  Used to parse libguestfs's own config files,
eg. F</etc/libguestfs-tools.conf>.

=item libselinux

Optional.  Used by the L<libvirt backend|guestfs(3)/BACKEND> to
securely confine the appliance (sVirt).

=item Berkeley DB utils (db_dump, db_load, etc)

Optional.  Usually found in a package called C<db-utils>,
C<db4-utils>, C<db4.X-utils> etc.

=item systemtap

Optional.  For userspace probes.

=item readline

Optional.  For nicer command line editing in L<guestfish(1)>.

=item acl

Optional.  Library and programs for handling POSIX ACLs.

=item libcap

Optional.  Library and programs for handling Linux capabilities.

=item libldm

Optional.  Library and L<ldmtool(1)> for handling
Windows Dynamic Disks.

=item sd-journal

Optional.  Library for accessing systemd journals.

=item gdisk

Optional.  GPT disk support.

=item netpbm

Optional.  Render icons from guests.

=item icoutils

Optional.  Render icons from Windows guests.

=item Perl C<Expect>

Optional.  Perl module used to test L<virt-rescue(1)>.

=item FUSE

Optional.  L<fusermount(1)>, libfuse and kernel module are all needed
if you want L<guestmount(1)> and/or L<mount-local|guestfs(3)/MOUNT LOCAL>
support.

=item static glibc

Optional.  Used only for testing.

=item qemu-nbd

Optional.  Used for testing, and by virt-p2v.

=item uml_mkcow

Optional.  For the L<UML backend|guestfs(3)/BACKEND>.

=item curl

Optional.  Used by virt-builder for downloads.

=item gpg

Optional.  Used by virt-builder for checking digital signatures.

=item liblzma

Optional.  If available, virt-builder will use this library
for fast, parallel uncompression of templates.

=item gtk2 E<ge> 2.24

Optional.  Used by the virt-p2v user interface.

=item zip

=item unzip

Optional.  Used by virt-v2v to handle OVA files.

=item python-evtx

Optional.  Used by L<virt-log(1)> to parse Windows Event Log files.

=item OCaml gettext

Optional.  For localizing OCaml virt tools.

=item ocaml-ounit E<ge> 2.0.0

Optional.  For testing the common OCaml modules.

=item ocaml-libvirt E<ge> 0.6.1.5

Optional.  For building the optional virt-v2v test harness.

=item Perl C<Module::Build> E<ge> 0.19

=item Perl C<Test::More>

Optional.  Used to build and test the Perl bindings.

=item Python E<ge> 2.2

Optional.  Used to build the Python bindings.  For building
Python 2 or Python 3 bindings, see
L</BUILDING PYTHON 2 AND PYTHON 3 BINDINGS> below.

=item Ruby

=item rake

=item rubygem-minitest

Optional.  Used to build the Ruby bindings.

=item Java E<ge> 1.6

Optional.  Java, JNI and jpackage-utils are needed for building Java
bindings.

=item GHC

Optional.  Used to build the Haskell bindings.

=item PHP

=item phpize

Optional.  Used to build the PHP bindings.

=item glib2

=item gobject-introspection

=item gjs

Optional.  Used to build and test the GObject bindings.

=item LUA

Optional.  Used to build the LUA bindings.

=item Erlang

=item erl_interface

Optional.  Used to build the Erlang bindings.

=item golang E<ge> 1.1.1

Optional.  Used to build the Go bindings.

=item valgrind

Optional.  For testing memory problems.

=item Perl C<Sys::Virt>

Optional.

=item libvirt-python

Optional.  For testing Python libvirt/libguestfs interactions.

=item Perl C<Win::Hivex>

Optional.  Used by the L<virt-win-reg(1)> tool.

=item Perl C<Pod::Usage>

Optional.  Used by some Perl virt tools.

=item Perl C<libintl>

Optional.

=item bash-completion

Optional.  For tab-completion of commands in bash.

=back

=head1 BUILDING FROM GIT

 git clone https://github.com/libguestfs/libguestfs
 cd libguestfs
 ./autogen.sh
 make

=head1 BUILDING FROM TARBALLS

Download and unpack the tarball.

 cd libguestfs-1.xx.yy
 ./configure
 make

=head1 RUNNING THE TESTS

To sanity check that the build worked, do:

 make quickcheck

To run the basic tests, do:

 make check

There are many more tests you can run.  See L<guestfs-hacking(1)>
for details.

=head1 INSTALLING

B<Do not use C<make install>!>  You'll end up with conflicting versions
of libguestfs installed, and this causes constant headaches for users.

Distro packagers can use:

 make INSTALLDIRS=vendor DESTDIR=[temp-build-dir] install

You can run L<guestfish(1)>, L<guestmount(1)> and the virt tools
without needing to install, using the F<./run> script in the top
directory.  This script sets up some environment variables.  For
example:

 ./run guestfish [usual guestfish args ...]

 ./run virt-inspector [usual virt-inspector args ...]

If you are already in the F<fish/> subdirectory, then the following
command will also work:

 ../run guestfish [...]

The F<./run> script adds every libguestfs binary to the C<$PATH>, so
the above example runs guestfish from the build directory (not the
globally installed guestfish if there is one).

You can also run the C programs under valgrind like this:

 ./run valgrind [valgrind opts...] virt-cat [virt-cat opts...]

or under gdb:

 ./run gdb --args virt-cat [virt-cat opts...]

This also works with sudo (eg. if you need root access for libvirt or
to access a block device):

 sudo ./run virt-cat -d LinuxGuest /etc/passwd

=head1 NOTES ABOUT QEMU AND KVM

A common problem is with broken or incompatible qemu releases.

Different versions of qemu have problems booting the appliance for
different reasons.  This varies between versions of qemu, and Linux
distributions which add their own patches.

If you find a problem, you could try using your own qemu built from
source (qemu is very easy to build from source), with a "qemu
wrapper".  See L<guestfs(3)/QEMU WRAPPERS>.

By default the configure script will look for qemu-kvm (KVM support).
KVM is much faster than using plain qemu.

You may also need to enable KVM support for non-root users, by
following these instructions:
L<http://www.linux-kvm.org/page/FAQ#How_can_I_use_kvm_with_a_non-privileged_user.3F>

On some systems, this will work too:

 chmod 0666 /dev/kvm

On some systems, the chmod will not survive a reboot, and you will
need to make edits to the udev configuration.

=head1 USING CLANG (LLVM) INSTEAD OF GCC

 export CC=clang
 ./configure
 make

Don't enable GCC warnings (ie. I<don't> use
C<./configure --enable-gcc-warnings>).

=head1 USING A PREBUILT BINARY APPLIANCE

To understand what the libguestfs appliance means, see
L<guestfs-internals(1)>.

If you are using non-Linux, or a Linux distribution that does not have
L<supermin(1)> support, or simply if you don't want to build your own
libguestfs appliance, then you can use one of the prebuilt binary
appliances that we supply:
L<http://libguestfs.org/download/binaries/appliance>

Build libguestfs like this:

 ./configure --disable-appliance --disable-daemon
 make

Set C<$LIBGUESTFS_PATH> to the path where you unpacked the appliance
tarball, eg:

 export LIBGUESTFS_PATH=/usr/local/lib/guestfs/appliance

and run the libguestfs programs and virt tools in the normal way,
eg. using the F<./run> script (see above).

=head1 BUILDING PYTHON 2 AND PYTHON 3 BINDINGS

The F<./configure> script detects the currently installed version of
Python using whatever program is called C<python> in the current
C<$PATH>.  Libguestfs will build Python 2 or Python 3 bindings as
appropriate.

You can override this behaviour by specifying an alternate Python
binary, eg:

 PYTHON=/usr/bin/python3 ./configure

To build parallel Python 2 and Python 3 bindings, you will need to
build libguestfs twice.  The second time, you can disable all the
other bindings and tools and just build the Python bindings.  See the
Fedora spec file (see below) for a complete example of how to do this.

=head1 BUILDING A PACKAGE FOR FEDORA

The Fedora spec file is stored under:
L<http://pkgs.fedoraproject.org/cgit/rpms/libguestfs.git/>

Libguestfs is built in Fedora using the ordinary Fedora build system
(Koji).

=head1 BUILDING A PACKAGE FOR RED HAT ENTERPRISE LINUX

Red Hat Enterprise Linux (RHEL) builds of libguestfs are heavily
patched.  There are broadly two types of patches we apply:

=over 4

=item *

We disable many features that we do not wish to support for RHEL
customers.  For example, the "libguestfs live" feature is disabled.

=item *

We backport upstream features.

=back

The patches we apply to RHEL releases are available publically in the
upstream git repository, in a branch called C<rhel-x.y>

For example, the RHEL 7.3 patches are available here:
L<https://github.com/libguestfs/libguestfs/commits/rhel-7.3>

The sources and spec files for RHEL versions of libguestfs are
available on L<ftp://ftp.redhat.com/>

=head1 BUILDING i686 32 BIT VIRT-P2V

I<(This section only applies on the x86-64 architecture.)>

Building a 32 bit virt-p2v (i686) binary improves compatibility with
older hardware.  See L<virt-p2v-make-disk(1)> for details.  Although
virt-p2v is a simple Gtk application, it is not especially easy to
build just virt-p2v as a 32 bit application on a 64 bit host.  Usually
the simplest way is to use a 32 bit chroot or even a 32 bit virtual
machine to build libguestfs.

On Fedora you can use the L<mock(1)> tool.  For example:

 fedpkg mockbuild --root fedora-23-i386

This will result in a F<virt-v2v-*.i686.rpm> file which can be
unpacked to extract the 32 bit virt-p2v binary.

The binary may be copied to either F<p2v/virt-p2v.i686>, or
F<$libexecdir/virt-p2v.i686> or F<$VIRT_P2V_DATA_DIR/virt-p2v.i686> as
appropriate.  This enables the L<virt-p2v-make-disk(1)> I<--arch>
option.

=head1 SEE ALSO

L<guestfs(3)>,
L<guestfs-examples(3)>,
L<guestfs-hacking(3)>,
L<guestfs-internals(3)>,
L<guestfs-performance(1)>,
L<guestfs-release-notes(1)>,
L<guestfs-testing(1)>,
L<libguestfs-test-tool(1)>,
L<libguestfs-make-fixed-appliance(1)>,
L<http://libguestfs.org/>.

=head1 AUTHORS

Richard W.M. Jones (C<rjones at redhat dot com>)

=head1 COPYRIGHT

Copyright (C) 2009-2016 Red Hat Inc.