Contributed by &a.jkh;, &a.gpalmer; and
&a.asami;.
The porting of freely available software, while perhaps not as gratifying as developing your own from scratch, is still a vital part of FreeBSD's growth and of great usefulness to those who would not otherwise know where to turn for it. All ported software is organized into a carefully organized hierarchy know as ``the ports collection''. The collection enables a new user to get a quick and complete overview of what is available for FreeBSD in an easy-to-compile form. It also saves considerable space by not actually containing the the majority of the sources being ported, but merely those differences required for running under FreeBSD.
What follows are some guidelines for creating a new port for
FreeBSD 2.x . The ${..} variable names you will
see in this document all refer to various user-overrideable defaults
used (and documented) by /usr/share/mk/bsd.port.mk.
Please refer to that file for more details on the inner workings of
the ports collection.
Note: Only a fraction of the overrideable variables are
mentioned in this document. Most (if not all) are documented
at the start of the bsd.port.mk file which can be
found in /usr/share/mk. This file uses a non-standard tab
setting. Emacs should recognize the setting on
loading the file. vi or ex can be set to
using the correct value by typing `:set tabstop=4'
once the file has been loaded.
You may come across code that needs modifications or
conditional compilation based upon what version of UNIX it is
running under. If you need to make such changes to the code
for conditional compilation, make sure you make the changes as
general as possible so that we can back-port code to FreeBSD
1.x systems and cross-port to other BSD systems such as 4.4BSD
from CSRG, BSD/386, 386BSD and NetBSD.
The preferred way to tell 4.3BSD/Reno and newer versions of
the BSD code apart is by using the `BSD' macro
defined in <sys/param.h>. Hopefully that file
is already included; if not, add the code:
Use sparingly:
In the dozens of ports that have been done, there have
only been one or two cases where __FreeBSD__
should have been used. Just because an earlier port
screwed up and used it in the wrong place does not mean
you should do so too.
This section tells you how to do a quick port. In many
cases, it is not enough, but we will see.
First, get the original tarball and put it into
${DISTDIR}, which defaults to
/usr/ports/distfiles.
Note: The following assumes that the software compiled
out-of-the-box, i.e., there was absolutely no change required
for the port to work on your FreeBSD box. If you needed to
change something, you will have to refer to the next section
too.
The minimal Makefile would look something like this:
See if you can figure it out. Do not worry about the contents
of the $Id$ line, it will be filled in
automatically by CVS when the port is imported to our main
ports tree.
There are three required description files that are
required for any port, whether they actually package or not.
They are COMMENT, DESCR, and
PLIST, and reside in the pkg subdirectory.
This is the one-line description of the port. It is
recommended to not have the name of the package at the
beginning, as in:
This is a longer description of the port. One to a few
paragraphs concisely explaining what the port does is
sufficient. Note: This is not a manual nor an
in-depth description on how to use or compile the port.
In particular, please do not just copy the README
file here, unless, of course, it is a concise description
of the port.
It is recommended that you sign the name at the end of
this file, as in:
This file lists all the files installed by the port. It
is also called the `packing list' because the package is
generated by packing the files listed here. The pathnames
are relative to the installation prefix (usually
/usr/local or /usr/X11R6).
Here is a small example:
Just type `make makesum'. The ports make rules
will automatically generate the file files/md5.
You should make sure that the port rules do exactly what
you want it to do, including packaging up the port. Try
doing `make install', `make package' and
then `pkg_delete -d <pkgname>' and see if all
the files are correctly deleted. Then do a `pkg_add
<pkgname>.tgz' and see if everything re-appears
and works correctly.
Now that you are happy with your port, the only thing
remaining is to put it in the main FreeBSD ports tree and
make everybody else happy about it too. To accomplish this,
pack the necessary files (everything described in this
section -- in particular do not include the
original source tarball or the `work' subdirectory)
into a .tar.gz file, stick it in the directory
Ok, so it was not that simple, and the port required some
modifications to get it to work. In this section, we will
explain, step by step, how to modify it to get it to work with
the ports paradigm.
First, this is the sequence of events which occurs when the
user first types `make' in your port's directory,
and you may find that having bsd.port.mk in another
window while you read this really helps to understand it.
But do not worry if you do not really understand what
bsd.port.mk is doing, not many people
do... :>
The above are the default actions. In addition, you can
define targets `pre-<something>' or
`post-<something>', or put scripts with those
names, in the scripts subdirectory, and they will
be run before or after the default actions are done.
For example, if you have a post-extract target
defined in your Makefile, and a file pre-build in
the scripts subdirectory, the
post-extract target will be called after the
regular extraction actions, and the pre-build
script will be executed before the default build rules are
done. It is recommended that you use Makefile targets if
possible, because it will be easier for someone to figure
out what kind of non-default action the port requires.
The default actions are done by the bsd.port.mk
targets `do-<something>'. For example, the
commands to extract a port are in the target
`do-extract'. If you are not happy with the
default target, and you cannot fix it by redefining the
`do-<something>' target in your Makefile.
Note that the `main' targets (e.g., extract,
configure, etc.) do nothing more than make sure all
the stages up to that one is completed and call the real
targets or scripts, and they are not intended to be
changed. If you want to fix the extraction, fix
do-extract, but never ever touch extract!
Now that you understand what goes on when the user types
`make', let us go through the recommended steps to
create the perfect port.
Get the original sources (normally) as a compressed tarball
(<foo>.tar.gz or <foo>.tar.Z)
and copy it into ${DISTDIR}. Always use
mainstream sources when and where you can.
If you cannot find a ftp site that is well-connected to the
net, or can only find sites that have irritatingly
non-standard formats, we can `house' it ourselves by putting
it on
If your port requires some additional `patches' that are
available on the Internet, fetch them too and put them in
${DISTDIR}. Do not worry if they come from
site other than where you got the the main source tarball,
we have a way to handle these situations (see the
description of ${PATCHFILES} below).
Unpack a copy of the tarball in a private directory and
make whatever changes are necessary to get the port to
compile properly under the current version of FreeBSD. Keep
careful track of everything you do, as you will be
automating the process shortly. Everything, including the
deletion, addition or modification of files should be doable
using an automated script or patch file when your port is
finished.
If your port requires significant user
interaction/customization to compile or install, you should
take a look at one of Larry Wall's classic Configure scripts
and perhaps do something similar yourself. The goal of the
new ports collection is to make each port as `plug-and-play'
as possible for the end-user while using a minimum of disk
space.
In the preparation of the port, files that have been added
or changed can be picked up with a recursive diff for later
feeding to patch. This is the easiest kind of change to
make as it does not involve any mucking around with
configuration files. Each set of patches you wish to apply
should be collected into a file named
`patch-<xx>' where <xx>
denotes the sequence in which the patches will be applied --
these are done in alphabetical order, thus
`aa' first, `ab' second and so on. These
files should be stored in ${PATCHDIR}, from
where they will be automatically applied. All patches
should be relative to ${WRKSRC} (generally
the directory your port's tarball unpacks itself into, that
being where the make is done). To make fixes and upgrades
easier you should avoid having more than one patch fix the
same file (e.g., patch-aa and patch-ab both changing
${WRKSRC}/foobar.c).
Include any additional customization commands to your
configure script and save it in the
`scripts' subdirectory. As mentioned above, you
can also do this as Makefile targets and/or scripts with the
name pre-configure or post-configure.
If your port requires user input to build, configure or
install, then set IS_INTERACTIVE in your Makefile.
This will allow `overnight builds' to skip your port if the
user sets the variable BATCH in his environment
(and if the user sets the variable INTERACTIVE,
then only those ports requiring interaction are
built).
Configuring the Makefile is pretty simple, and again we
suggest that you look at existing examples before
starting. Consider the following problems in sequence as
you design your new Makefile:
Does it live in ${DISTDIR} as a standard
gzip'd tarball? If so, you can go on to the next step. If
not, you should look at overriding any of the
${EXTRACT_CMD},
${EXTRACT_BEFORE_ARGS},
${EXTRACT_AFTER_ARGS},
${EXTRACT_SUFX}, or
${DISTFILE} variables, depending on how
alien a format your port's distribution file is. (The most
common case is `EXTRACT_SUFX=.tar.Z', when the
tarball is condensed by regular compress, not gzip.)
In the worst case, you can simply create your own
`do-extract' target to override the default, though
this should be rarely, if ever, necessary.
You should set ${DISTNAME} to be the base
name of your port. The default rules expect the
distribution file list (${DISTFILES}) to be
named
${DISTNAME}${EXTRACT_SUFX}
by default which, if it is a normal tarball, is going to be
something like:
When a package is created, it is put under
/usr/ports/packages/All and links are made from one
or more subdirectories of /usr/ports/packages. The
names of these subdirectories are specified by the variable
${CATEGORIES}. It is intended to make life
easier for the user when he is wading through the pile of
packages on the ftp site or the CD-ROM. Please take a look
at the existing categories (some of them have different
names from subdirectories of /usr/ports) and pick
the ones that are suitable for your port. If your port
truly belongs to something that is different from all the
existing ones, you can even create a new category name.
If you have a ftp-URL pointing at the the original tarball,
record the directory containing the tarball in
${MASTER_SITES}. This will provide a backup
site, as well as a direct pointer to the original source
location. Do not forget the trailing slash (/)!
The make macros will try to use this specification for
grabbing the distribution file with ${NCFTP}
if they cannot find it already on the system.
It is recommended that you put multiple sites on this list,
preferably from different continents. This will safeguard
against wide-area network problems, and we are even planning
to add support for automatically determining the closest
master site and fetching from there!
If your port requires some additional patches that are
available by ftp, set ${PATCHFILES} to the
names of the files and ${PATCH_SITES} to the
URL of the directory that contains them (the format is the
same as ${MASTER_SITES}).
If the patch is not relative to the top of the source tree
(i.e., ${WKRSRC}) because it contains some
extra pathnames, set ${PATCH_DIST_STRIP}
accordingly. For instance, if all the pathnames in the
patch has an extra `foozolix-1.0/' in front of the
filenames, then set `PATCH_DIST_STRIP=-p1'.
Do not worry if the patches are compressed, they will be
decompressed automatically if the filenames end with
`.gz' or `.Z'.
Set your mail-address here. Please. :)
Many ports depend on other ports. There are five
variables that you can use to ensure that all the required
bits will be on the user's machine.
This variable specifies the shared libraries this port
depends on. It is a list of `lib:dir' pairs
where lib is the name of the shared library, and
dir is the directory in which to find it in case
it is not available. For example,
This variable specifies executables this port depends on
during run-time. It is a list of `exec:dir'
pairs where exec is the name of the executable,
and dir is the directory in which to find it in
case it is not available. For example,
This variable specifies executables this port requires to
build. Like RUN_DEPENDS, it is a list of
`exec:dir' pairs. For example,
This variable specifies executables this port requires to
fetch. Like the previous two, it is a list of
`exec:dir' pairs. For example,
If there is a dependency that does not fall into either of
the above four categories, or your port requires to have
the source of the other port extracted (i.e., having them
installed is not enough), then use this variable. This is
just a list of directories, as there is nothing to check,
unlike the previous two.
If your package uses GNU make, set
`USE_GMAKE=yes'. If your package uses GNU
configure, set `GNU_CONFIGURE=yes'. If
you want to override the default GNU configure
arguments from `--prefix=${PREFIX}' to
something else, set those arguments in
${CONFIGURE_ARGS}.
If your package uses imake (e.g. is an X
application that has an Imakefile), then set
`USE_IMAKE=yes'. This will cause the configure
stage to automatically do an xmkmf -a. If the
`-a' flag is a problem for your port, set
`XMKMF=xmkmf'.
If your port's source Makefile has something else than
`all' as the main build target, set
${ALL_TARGET} accordingly. Same goes for
`install' and ${INSTALL_TARGET}.
If the port uses imake but does not understand the
`install.man' target,
`NO_INSTALL_MANPAGES=yes' should be set. In
addition, the author of the original port should be shot.
Some software packages have restrictive licenses or are in
violation to the law (PKP's patent on public key crypto,
ITAR (export of crypto software) to name just two of them).
What we can do with them vary a lot, depending on the exact
wordings of the respective licenses.
Note that it is your responsibility as a porter to read the
licensing terms of the software and make sure that the FreeBSD
project will not be held accountable of violating them by
redistributing the source or compiled binaries either via ftp
or CD-ROM. If in doubt, please contact the &a.ports;.
We usually get around this problem by setting
${NO_PACKAGE} in the Makefile, and not putting
the distfile up for ftp. However, for most cases, you should
at least be able to make a port, so do not let the license
scare you away!
Note: The GNU General Public License (GPL), both version 1
and 2, should not be a problem for ports.
Note: If you are a committer, make sure you update the
ports/LEGAL file too.
This section is still under construction, sorry.
Here is a list of common do's and dont's that you encounter
during the porting process.
Do not leave anything valuable lying around in the
`work' subdirectory, `make clean' will
nuke it completely! If you need auxiliary files
that are not scripts or patches, put them in the subdirectory
`files' and use the post-extract target to
copy them to the `work' subdirectory.
Do install package information, i.e., the three files in
pkg. Note that these files are not used only for
packaging anymore, and are mandatory now, even if
${NO_PACKAGE} is set.
Do compress manpages and strip binaries. If the original
source already does that, fine; otherwise, you can add a
post-install rule to do it yourself. Make sure
that you check the variable NOMANCOMPRESS that the
user can set in /etc/make.conf to disable man page
compression. Here is an example:
Use the file command on the installed executable
to check whether the binary is stripped or not. If it
does not say `not stripped', it is stripped.
If your software has some documentation other than the
standard man and info pages that you think is useful for the
user, install it under ${PREFIX}/share/doc.
This can be done, like the previous item, in the
post-install target.
Create a new directory for your port. The directory name
should reflect what the port is. This usually means
${PKGNAME} minus the version part. However,
if you think the user might want different versions of the
port to be installed at the same time (e.g., tcl/tk), you
can use the whole ${PKGNAME}.
Make the installation dependent to the variable
NOPORTDOCS so that users can disable it in
/etc/make.conf, like this:
Do not forget to add them to pkg/PLIST too! (Do not
worry about NOPORTDOCS here; there is currently no
way for the packages to read variables from
/etc/make.conf.)
Do not let your port clutter /usr/ports/distfiles. If
your port requires a lot of files (including patchfiles) to be
fetched, or contains a file that has a name that might conflict
with other ports (e.g., `Makefile'), set
${DIST_SUBDIR} to the name of the port
(${PKGNAME} without the version part should work
fine). This will change ${DISTDIR} from the
default /usr/ports/distfiles to
/usr/ports/distfiles/${DIST_SUBDIR}, and in
effect puts everything that is required for your port into that
subdirectory.
It will also look at the subdirectory with the same name on the
backup master site at ftp.freebsd.org. (Setting
${DISTDIR} explicitly in your Makefile will not
accomplish this, so please use ${DIST_SUBDIR}.)
Note this does not affect the ${MASTER_SITES}
you define in your Makefile.
Do not rely on custom utilities in your local configure
script or anything -- they may not be there on the user's
system! If you really need something else to be installed
before you can work, detect this from your configure script,
print a helpful message and exit with a non-zero status! At
least you will have given the user some idea of what is needed.
If the custom utility or package is actually part of the
ports tree, this should be dealt by the dependency mechanism
of ports.
Actually, if this utility is not part of the ports tree you
should probably make a port of this utility (this is how
many of the ports made it into the tree!). Depending on
something that is not part of the main FreeBSD distribution
or the ports tree is a bad idea, and the user should be able
to go to any subdirectory of /usr/ports and type
`make' and have that port, as well as everything it
requires, built automatically.
Do send applicable changes/patches to the original
author/maintainer for inclusion in next release of the code.
This will only make your job that much easier for the next
release.
Do not put RCS strings in patches. CVS will mangle them
when we put the files into the ports tree, and when we check
them out again, they will come out different and the patch
will fail. RCS strings are surrounded by dollar
(`$') signs, and typically start with
`$Id' or `$RCS'.
Using the recurse (`-r') option to diff
to generate patches is fine, but please take a look at the
resulting patches to make sure you don't have any
unnecessary junk in there. In particular, diffs between two
backup files, Makefiles when the port uses imake or GNU
configure, etc., are unnecessary and should be deleted.
Also, if you had to delete a file, then you can do it in the
post-extract target rather than as part of the
patch.
Do try to make your port install relative to
${PREFIX}. (The value of this variable will be
set to ${LOCALBASE} (default
/usr/local), unless ${USE_IMAKE} or
${USE_X11} is set, in which case it will be
${X11BASE} (default /usr/X11R6).)
Not hard-coding `/usr/local' or `/usr/X11R6'
anywhere in the source will make the port much more flexible and
able to cater to the needs of other sites. For X ports that use
imake, this is automatic; otherwise, this can often be done by
simply replacing the occurrences of `/usr/local' (or
`/usr/X11R6' for X ports that do not use imake) in the
various scripts/Makefiles in the port to read
`${PREFIX}', as this variable is automatically
passed down to every stage of the build and install processes.
The variable ${PREFIX} can be reassigned in your
Makefile or in the user's environment. However, it is strongly
discouraged for individual ports to set this variable explicitly
in the Makefiles. (If your port is an X port but does not use
imake, set USE_X11=yes; this is quite different from
setting PREFIX=/usr/X11R6.)
Also, refer to programs/files from other ports with the
variables mentioned above, not explicit pathnames. For instance,
if your port requires a macro PAGER to be the full
pathname of less, use the compiler flag:
Try to let the port put things in the right subdirectories
of ${PREFIX}. Some ports lump everything
and put it in the subdirectory with the port's name, which is
incorrect. Also, many ports put everything except binaries,
header files and manual pages in the a subdirectory of
`lib', which does not bode well with the BSD
paradigm. Many of the files should me moved to one of the
following: `etc' (setup/configuration files),
`libexec' (executables started internally),
`sbin' (executables for superusers/managers) or
`share' (architecture independent files). See
hier(7) for details, the rule governing
/usr pretty much applies to /usr/local
too.
If your port installs a shared library, add a
post-install target to your Makefile that runs
`/sbin/ldconfig -m' on the directory where the new
library is installed (usually ${PREFIX}/lib)
to register it into the shared library cache.
Also, add an @exec line to your pkg/PLIST
file so that a user who installed the package can start
using the shared library immediately. This line should
immediately follow the line for the shared library itself,
as in:
Note: the `-m' option is new since 2.0.5 and
2.1.0-950726-SNAP, so do not be alarmed if it does not work on
your machine.
Never, ever, ever add a line that says
`ldconfig' without any arguments to your Makefile
or pkg/PLIST. This will reset the shared library cache to
the contents of /usr/lib only, and will royally
screw up the user's machine ("Help, xinit does not run
anymore after I install this port!"). Anybody who does this
will be shot and cut into 65,536 pieces by a rusty knife and
have his liver chopped out by a bunch of crows and will
eternally rot to death in the deepest bowels of hell (not
necessarily in that order)....
Do look at existing examples and the bsd.port.mk
file before asking us questions! ;)
Do ask us questions if you have any trouble! Do not just
beat your head against a wall! :)
Here is a sample Makefile that you can use to create a new
port. Make sure you remove all the extra comments (ones
between brackets)!
It is recommended that you follow this format (ordering of
variables, etc.). Not all of the existing Makefiles are in
this format (mostly old ones), but we are trying to uniformize
how they look. This format is designed so that the most
important information is easy to locate.
The following are the conventions you should follow in
naming your packages. This is to have our package directory
easy to scan, as there are already lots and lots of packages
and users are going to turn away if they hurt their eyes!
If your ${DISTNAME} does not look like
`<name>-<version.string.numbers>', set
${PKGNAME} to something in that format.
Here are some (real) examples on how to convert a
${DISTNAME} into a suitable
${PKGNAME}:
If there is absolutely no trace of version information in the
original source and it is unlikely that the original author
will ever release another version, just set the version string
to `1.0' (like the piewm example above). Otherwise, ask the
original author or use the date string (`yy.mm.dd') as the
version.
Boy, this sure was a long tutorial, wasn't it? Thanks for
following us to here, really.
Well, now that you know how to do a port, let us go at it and
convert everything in the world into ports! That is the
easiest way to start contributing to the FreeBSD Project!
:)