guestfs-building man page

guestfs-building — How to build libguestfs from source

Description

This manual page describes how to build libguestfs from source.

The main steps are:

·
Install the requirements.
·
Build, either from the git repository or from a tarball.
·
Run the tests.
·
Run the tools from the source directory, or install.

Requirements

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

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

dnf builddep libguestfs

On systems still using yum(8), do:

yum-builddep libguestfs

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 http://packages.debian.org/source/libgu…, at the list of "build-depends" and "build-depends-indep", and install everything listed there.

Full list of requirements

appliance/packagelist.in

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

Note: If you build libguestfs followed by installing appliance packages, the build will not pick them up automatically, even if you do "make clean". You have to do this command to clean the old supermin appliance and force a new one to be prepared:

make -C appliance clean-supermin-appliance
qemu ≥ 1.3.0
Required.
qemu-img ≥ 1.3.0
Required. Virt-p2v and virt-v2v requires qemu-img ≥ 2.2.0.
kernel ≥ 2.6.34
Required. The following features must be enabled: "virtio-pci", "virtio-serial", "virtio-block", "virtio-net".
supermin ≥ 5.1.0
Required. For alternatives, see "Using a Prebuilt Binary Appliance" below.
glibc
Required. We use various glibc-isms, and glibc also provides XDR libraries and the "rpcgen" tool.
Gcc or Clang
Required. We use "__attribute__((cleanup))" which is a GCC extension also supported by Clang.
Perl
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.
Perl "Pod::Man"
Perl "Pod::Simple"
Required. Part of Perl core.
OCaml ≥ 3.11
OCaml findlib
Required if compiling from git. Optional (but recommended) if compiling from tarball.
autoconf
automake
gettext
Required if compiling from git. Optional if compiling from tarball.
cpio
Required.
gperf
Required.
flex
bison
Required.
Perl-compatible Regular Expressions (PCRE) library
Required.
genisoimage
Required.
libxml2
Required.
ncurses
Required.
augeas ≥ 1.0.0
Required.
xz
Required.
yajl ≥ 2.0.4
Required.
po4a
Required if compiling from git. Optional if compiling from tarball.
hivex ≥ 1.2.7
Required if compiling from git, and highly recommended otherwise. Various core features will be disabled if hivex is not available.
libmagic
Optional. This is the library used by the file(1) command.
libvirt ≥ 0.10.2
Optional. Always use the latest possible version of libvirt.
xmllint
Optional. Used only for tests.
libconfig
Optional. Used to parse libguestfs's own config files, eg. /etc/libguestfs-tools.conf.
libselinux
Optional. Used by the libvirt backend to securely confine the appliance (sVirt).
Berkeley DB utils (db_dump, db_load, etc)
Optional. Usually found in a package called "db-utils", "db4-utils", "db4.X-utils" etc.
systemtap
Optional. For userspace probes.
readline
Optional. For nicer command line editing in guestfish(1).
acl
Optional. Library and programs for handling POSIX ACLs.
libcap
Optional. Library and programs for handling Linux capabilities.
libldm
Optional. Library and ldmtool(1) for handling Windows Dynamic Disks.
sd-journal
Optional. Library for accessing systemd journals.
gdisk
Optional. GPT disk support.
netpbm
Optional. Render icons from guests.
icoutils
Optional. Render icons from Windows guests.
Perl "Expect"
Optional. Perl module used to test virt-rescue(1).
FUSE
Optional. fusermount(1), libfuse and kernel module are all needed if you want guestmount(1) and/or mount-local support.
static glibc
Optional. Used only for testing.
qemu-nbd
Optional. Used for testing, and by virt-p2v.
uml_mkcow
Optional. For the UML backend.
curl
Optional. Used by virt-builder for downloads.
gpg
Optional. Used by virt-builder for checking digital signatures.
liblzma
Optional. If available, virt-builder will use this library for fast, parallel uncompression of templates.
Gtk ≥ 2.24, or 3
Optional.

Used by the virt-p2v graphical user interface.

Either Gtk 2 or Gtk 3 can be used. If you want to select a specific version of Gtk, use "./configure --with-gtk=2" or "./configure --with-gtk=3".
D-Bus
Optional.

If the D-Bus low level C API is available, virt-p2v can send a D-Bus message to logind to inhibit power saving (sleep, suspend, etc) during P2V conversions.

If this API is not available at build time, then very long conversions might be interrupted if the physical machine goes to sleep.
zip
unzip
Optional. Used by virt-v2v to handle OVA files.
python-evtx
Optional. Used by virt-log(1) to parse Windows Event Log files.
OCaml gettext
Optional. For localizing OCaml virt tools.
ocaml-ounit ≥ 2.0.0
Optional. For testing the common OCaml modules.
ocaml-libvirt ≥ 0.6.1.5
Optional. For building the optional virt-v2v test harness.
Perl "Module::Build" ≥ 0.19
Perl "Test::More"
Optional. Used to build and test the Perl bindings.
Python ≥ 2.2
Optional. Used to build the Python bindings. For building Python 2 or Python 3 bindings, see "Building Python 2 and Python 3 Bindings" below.
Python "unittest"
Optional. Used to run the Python testsuite.
Ruby
rake
rubygem-minitest
rubygem-rdoc
Optional. Used to build the Ruby bindings.
Java ≥ 1.6
Optional. Java, JNI and jpackage-utils are needed for building Java bindings.
GHC
Optional. Used to build the Haskell bindings.
PHP
phpize
Optional. Used to build the PHP bindings.
glib2
gobject-introspection
gjs
Optional. Used to build and test the GObject bindings.
LUA
Optional. Used to build the LUA bindings.
Erlang
erl_interface
Optional. Used to build the Erlang bindings.
golang ≥ 1.1.1
Optional. Used to build the Go bindings.
valgrind
Optional. For testing memory problems.
Perl "Sys::Virt"
Optional.
libvirt-python
Optional. For testing Python libvirt/libguestfs interactions.
Perl "Win::Hivex"
Optional. Used by the virt-win-reg(1) tool.
Perl "Pod::Usage"
Optional. Used by some Perl virt tools.
Perl "libintl"
Optional.
bash-completion
Optional. For tab-completion of commands in bash.
libtsk
Optional. Library for filesystem forensics analysis.

Building from Git

You will need to install additional dependencies "autoconf", "automake", "gettext", OCaml findlib and po4a when building from git.

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

Building from Tarballs

Download and unpack the tarball.

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

Running the Tests

DO NOT run the tests as root! Libguestfs can be built and tested as non-root. Running the tests as root could even be dangerous, don't do it.

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 guestfs-hacking(1) for details.

Installing

DO NOT use "make install"! You'll end up with conflicting versions of libguestfs installed, and this causes constant headaches for users. See the next section for how to use the ./run script instead.

Distro packagers can use:

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

THE ./run SCRIPT

You can run guestfish(1), guestmount(1) and the virt tools without needing to install them by using the ./run script in the top directory. This script works by setting several environment variables.

For example:

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

The ./run script adds every libguestfs binary to the $PATH, so the above examples run guestfish and virt-inspector from the build directory (not the globally installed guestfish if there is one).

You can use the script from any directory. If you wanted to run your own libguestfs-using program, then the following command will also work:

/path/to/libguestfs/run ./my_program [...]

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

To set environment variables, you can either do:

LIBGUESTFS_HV=/my/qemu ./run guestfish

or:

./run env LIBGUESTFS_HV=/my/qemu guestfish

local* FILES

Files in the top source directory that begin with the prefix local* are ignored by git. These files can contain local configuration or scripts that you need to build libguestfs.

I have a file called localconfigure which is a simple wrapper around autogen.sh containing local configure customizations that I need. It looks like this:

. localenv
./autogen.sh \
    -C \
    --enable-werror \
    "$@"

So I can use this to build libguestfs:

./localconfigure && make

If there is a file in the top build directory called localenv, then it will be sourced by "make". This file can contain any local environment variables needed, eg. for skipping tests:

# Use an alternate python binary.
export PYTHON=python3
# Skip this test, it is broken.
export SKIP_TEST_BTRFS_FSCK=1

Note that localenv is included by the top Makefile (so it's a Makefile fragment). But if it is also sourced by your localconfigure script then it is used as a shell script.

SELECTED ./configure SETTINGS

There are many "./configure" options. Use:

./configure --help

to list them all. This section covers some of the more important ones.

--disable-appliance --disable-daemon
See "Using a Prebuilt Binary Appliance" below.
--disable-erlang
--disable-gobject
--disable-golang
--disable-haskell
--disable-lua
--disable-ocaml
--disable-perl
--disable-php
--disable-python
--disable-ruby
Disable specific language bindings, even if "./configure" finds all the necessary libraries are installed so that they could be compiled.

Note that disabling OCaml or Perl will have the knock-on effect of disabling large numbers of virt tools and parts of the test suite.
--disable-fuse
Disable FUSE support in the API and the guestmount(1) tool.
--disable-gnulib-tests
On some platforms the GNUlib test suite can be flaky. This disables it, since errors in the GNUlib test suite are often not important.
--disable-static
Don't build a static linked version of the libguestfs library.
--enable-install-daemon
Normally guestfsd(8) is not installed by "make install", since that wouldn't be useful (instead it is "installed" inside the supermin appliance). However if packagers are building "libguestfs live" then they should use this option.
--enable-werror
This turns compiler warnings into errors (ie. "-Werror"). Use this for development, especially when submitting patches. It should generally not be used for production or distro builds.
--with-default-backend=libvirt
This controls the default method that libguestfs uses to run qemu (see "BACKEND" in guestfs(3)). If not specified, the default backend is "direct", which means libguestfs runs qemu directly.

Fedora and Red Hat Enterprise Linux (RHEL) ≥ 7 use this flag to change the default backend to "libvirt", because (especially in RHEL) the policy is not to allow any program to run qemu except via libvirt.

Note that despite this setting, all backends are built into libguestfs, and you can override the backend at runtime by setting the $LIBGUESTFS_BACKEND environment variable (or using API methods).
--with-extra="distroname=version,libvirt,..."
--with-extra="local"
This option controls the "extra" field returned by "guestfs_version" in guestfs(3) and also printed by virt tools' --version option. It is a free text field, but a good idea is to encode a comma-separated list of facts such as the distro name and version, whether libvirt is the default backend, and anything else that may help with debugging problems raised by users.

For custom and/or local builds, this can be set to "local" to indicate this is not a distro build.
--without-libvirt
Compile libguestfs without libvirt support, even if libvirt development libraries are installed.
--with-gtk=2
This option forces virt-p2v to be built against Gtk 2, which is currently the most widely tested configuration.
--with-qemu="bin1 bin2 ..."
Provide an alternate qemu binary (or list of binaries). This can be overridden at runtime by setting the "LIBGUESTFS_HV" environment variable.
--with-qemu-options="-M ... -cpu ..."
If qemu requires extra options to work on this platform, you can pass them here, and they will be used both when testing and running qemu.
--with-supermin-packager-config=yum.conf
This passes the --packager-config option to supermin(1).

The most common use for this is to build the appliance using an alternate repository (instead of using the installed yum/dnf/apt/etc configuration to find and download packages). You might need to use this if you want to build libguestfs without having a network connection. Examples of using this can be found in the Fedora "libguestfs.spec" file (see "Building a Package for Fedora" below for resources).
--with-supermin-extra-options="--opt1 --opt2 ..."
Pass additional options to supermin(1). See appliance/make.sh.in to understand precisely what this does.
PYTHON
This environment variable may be set to point to a python binary (eg. "python3"). When "./configure" runs, it inspects this python binary to find the version of Python, the location of Python libraries and so on. See "Building Python 2 and Python 3 Bindings" below.
SUPERMIN
This environment variable can be set to choose an alternative supermin(1) binary. This might be used, for example, if you want to use a newer upstream version of supermin than is packaged for your distro, or if supermin is not packaged at all. On RHEL 7, you must set "SUPERMIN=/usr/bin/supermin5" when compiling libguestfs.

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 "QEMU WRAPPERS" in guestfs(3).

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: http://www.linux-kvm.org/page/FAQ#How_c…

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.

Using Clang (Llvm) Instead of Gcc

export CC=clang
./configure
make

Using a Prebuilt Binary Appliance

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

If you are using non-Linux, or a Linux distribution that does not have 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: http://libguestfs.org/download/binaries…

Build libguestfs like this:

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

Set $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 ./run script (see above).

Building Python 2 and Python 3 Bindings

The ./configure script detects the currently installed version of Python using whatever program is called "python" in the current $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.

Building a Package for Fedora

The Fedora spec file is stored under: http://pkgs.fedoraproject.org/cgit/rpms…

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

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:

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

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

For example, the RHEL 7.3 patches are available here: https://github.com/libguestfs/libguestf…

The sources and spec files for RHEL versions of libguestfs are available on https://git.centos.org/project/rpms, and see also https://wiki.centos.org/Sources.

BUILDING i686 32 BIT VIRT-P2V

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

Building a 32 bit virt-p2v (i686) binary improves compatibility with older hardware. See 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 mock(1) tool. For example:

fedpkg mockbuild --root fedora-23-i386

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

The binary may be compressed to either p2v/virt-p2v.i686.xz, or $libdir/virt-p2v/virt-p2v.i686.xz or $VIRT_P2V_DATA_DIR/virt-p2v.i686.xz as appropriate. This enables the virt-p2v-make-disk(1) --arch option.

See Also

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

Authors

Richard W.M. Jones ("rjones at redhat dot com")

License

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

Bugs

To get a list of bugs against libguestfs, use this link: https://bugzilla.redhat.com/buglist.cgi…

To report a new bug against libguestfs, use this link: https://bugzilla.redhat.com/enter_bug.c…

When reporting a bug, please supply:

·
The version of libguestfs.
·
Where you got libguestfs (eg. which Linux distro, compiled from source, etc)
·
Describe the bug accurately and give a way to reproduce it.
·
Run libguestfs-test-tool(1) and paste the complete, unedited output into the bug report.

Referenced By

guestfs(3), guestfs-hacking(1), guestfs-release-notes(1), virt-p2v-make-disk(1).

2016-10-25 libguestfs-1.35.14 Virtualization Support