.Dd February 13, 2018
.Dt APKBUILD 5 PRM
.Os "Alpine Linux"
.Sh NAME
.Nm APKBUILD
.Nd metadata and instructions to build a package
.Sh SYNOPSIS
.Nm /usr/src/packages/<repo>/<package>/APKBUILD
.Sh DESCRIPTION
An
.Nm
file is used by tools such as
.Xr abuild 1
to build a package for eventual installation by the
.Xr apk 8
package manager.
It defines metadata such as the name of the package, the version information,
the source license, and contact information for the developer.
It additionally contains the commands needed to build, test, and install the
package.
.Pp
The
.Nm
format is similar to a typical shell script; you set pre-defined variables and
implement pre-defined functions, and the
.Xr abuild 1
(or similar) utility will use them to create the package.
.Ss Required Variables
The following variables must be set in all
.Nm
files:
.Bl -tag -width Ds
.It Cm pkgname
Specifies name of the package.
This is typically the name of the package upstream; however, note that all
letters must be lowercased.
.Pp
Libraries for scripting languages should have a prefix before the library name
describing the language.
Such prefixes include
.Em lua- ,
.Em perl- ,
.Em py- ,
and
.Em rb- .
Not all languages use prefixes.
For a definitive list, consult the PREFIXES file in the root directory of the
repository you are using for packaging.
.It Cm pkgver
Specifies the version of the software being packaged.
The version of a package must consist of one or more numbers separated by the
radix (decimal point).
The final number may have a single letter following it, for upstreams that use
such a versioning scheme (such as 1.5a, 1.5b, 1.5c).
.Pp
After the final number (and optional single letter), a suffix may be appended,
which must be an underscore (_) followed by one of
.Em alpha ,
.Em beta ,
.Em pre ,
.Em rc ,
.Em cvs ,
.Em svn ,
.Em git ,
.Em hg ,
or
.Em p ,
optionally followed by another number.
If the suffix is
.Em alpha ,
.Em beta ,
.Em pre ,
or
.Em rc ,
it is considered to be earlier than the version without a suffix; if the suffix
is
.Em cvs ,
.Em svn ,
.Em git ,
.Em hg ,
or
.Em p ,
it is considered to be later than the version without a suffix.
All of the following examples are valid versions, in order from lowest to
highest:
.Pp
1.0, 1.1_alpha2, 1.1.3_pre, 1.1.3, 1.1.3_hg, 1.2, 1.2a, 1.2b
.It Cm pkgrel
Specifies the package release number of this particular package version.
This indicates when a package has changed without a corresponding change in
version.
Always increment
.Cm pkgrel
when you change the contents, dependencies, or metadata of a package.
The first release of a package is always
.Li 0 .
.It Cm pkgdesc
Specifies what the package contains.
.Cm pkgdesc
must be 128 characters or less, and should concisely describe what actions the
software or items being packaged will allow the user to perform.
For example,
.Dq Fully-featured word processor with spell check and many plugins
would be a sufficient
.Cm pkgdesc
for AbiWord.
.It Cm url
Specifies the Web address of the package's upstream.
This allows users and future maintainers to find documentation, release
information, and contact information for the package.
If no Web address is available for the package, you must set
.Cm url
to an empty string ("").
.It Cm arch
Specifies the architectures for which the package may be built.
It is highly recommended that you set this variable to "all" if the package is
portable.
.Pp
You may use "noarch" if the package does not contain any architecture-specific
binary files - that is, any files that are compiled for the target only.
Such packages may include pure Python packages, shell script packages, and
JARs.
If you are not sure what this means, using "all" is safe.
.It Cm license
Specifies the license under which the package is distributed.
The value provided must match a SPDX license identifier.
.It Cm source
Specifies the location of both local and remote source files used to build the
package.
Typically, the remote source file(s) or archive(s) is specified, followed by
any local patches, install scripts, configuration files, or other necessary
files.
.El
.Ss Optional Variables
The following variables are not required, but may be set in any
.Nm
file:
.Bl -tag -width Ds
.It Cm checkdepends
Specifies test-time dependencies of the package.
Common packages that are used for testing include check, dejagnu, and
perl-test-command.
.It Cm depends
Specifies the run-time dependencies of the package.
The
.Xr abuild 1
utility will automatically scan the resultant package for shared library (.so)
dependencies; do not specify them here.
.It Cm install
Specifies install scripts for the package, if any.
See
.Sx Install Scripts
for more information about install scripts.
.It Cm install_if
Specifies a condition when
.Xr apk 8
should automatically install the package (or subpackage).
For instance, the OpenRC subpackages set
.Cm install_if
to
.Li $pkgname=$pkgver openrc
which means that the OpenRC subpackage will be automatically installed if the
origin package and OpenRC are both installed on the same computer.
.It Cm makedepends
Specifies build dependencies for the package.
.It Cm pkggroups
Specifies a space-separated list of login groups to create during build-time.
Note that you will need to create the login groups in a pre-install install
script as well; see
.Sx Install Scripts
for more information about install scripts.
.It Cm pkgusers
Specifies a space-separated list of user logins to create during build-time.
Note that you will ned to create the user logins in a pre-install install
script as well; see
.Sx Install Scripts
for more information about install scripts.
.It Cm provides
Specifies that the package "provides" the same contents as another package.
There are two formats that you may use for
.Cm provides :
a provider name, and a provider name with version.
.Pp
Specifying a provider name with version such as
.Li foobar=1.2
will cause the package to be an "alias" of foobar version 1.2.
It will be automatically installed if a user then runs
.Li apk add foobar
or similar, and it will conflict with a package named foobar.
.Pp
Specifying a provider name without a version such as
.Li baz
will cause the package to provide a "virtual" called baz.
Multiple packages with the same virtual provider can be installed on a system;
however, if a user runs
.Li apk add baz
they will provided a list of packages that provide baz and must select one and
install it.
.It Cm provider_priority
Specifies the numeric value for
.Xr apk 8
to use for the package when considering which provider should be installed for
the same
.Cm provides
virtual provider.
.It Cm replaces
Specifies packages that the package replaces.
This is typically used for packages renamed by upstream.
.It Cm subpackages
Specifies subpackages or split packages built with this package.
Typically, this will include
.Li $pkgname-dev
for development files (such as /usr/include and static library files) and
.Li $pkgname-doc
for documentation (such as /usr/share/doc and /usr/share/man).
.Pp
Each subpackage may be specified using three different methods.
The first, and most common, is
.Li $pkgname-foo
where
.Li foo
is the name of the split function specified later in the file.
Similar to the
.Cm package
function, the
.Li foo
function must move files from
.Pa $pkgdir
or
.Pa $srcdir
to
.Pa $subpkgdir
after creating
.Pa $subpkgdir .
.Pp
The second method is to simply call the subpackage
.Li foo
which will create a package called
.Li foo
instead of pkgname-foo.
.Pp
However,
.Li foo
in both of these examples cannot contain a hyphen, as shell function names
cannot have hyphens in them.  In this case, the third method may be used:
.Li foo:funcname
where
.Li foo
is the name of the subpackage and
.Li funcname
is the name of the shell function in the
.Nm
that creates it.
.Pp
Note that an additional colon may be used to specify an architecture for the
subpackage; typically, this is used for marking miscellaneous files that are
not architecture-specific as noarch.
For example,
.Li $pkgname-doc $pkgname-foo $pkgname-foo-misc:foo_misc:noarch
will create the $pkgname-doc package using the
.Cm doc
function, the $pkgname-foo package using the
.Cm foo
function, and the $pkgname-foo-misc package using the
.Cm foo_misc
function and set $pkgname-foo-misc as noarch.
.It Cm triggers
Specifies a trigger script used by the package.
A trigger script is a shell script that is called whenever monitored files or
directories are modified.
You may specify the paths to monitor using the triggers variable as follows:
.Pp
.Li $pkgname.trigger=/usr/share/man:/usr/local/share/man
.Pp
This will run the package trigger script whenever files in
.Pa /usr/share/man
or
.Pa /usr/local/share/man
are created, modified, or removed.
.El
.Ss options
The
.Cm options
variable allows you to set parameters for the package at build time.
There are a number of valid options you may set, and you may set multiple
options by writing a space between each one.
.Bl -tag -width Ds
.It Cm !archcheck
Specifies that the package contains binaries that cannot run on the target
architecture.
This is primarily used for packages containing firmware, and should typically
never need to be used.
.It Cm charset.alias
Specifies that the package ships a /usr/lib/charset.alias file and that it
should be installed on the user's system.
This is almost never the case.
Do not use this option.
.It Cm !check
Specifies that the package will not run a test suite.
The reason for disabling the check phase should be noted in a comment.
.It Cm checkroot
Specifies that the package's test suite will be run in
.Xr fakeroot 8 .
This is necessary for some test suites which fail when run as non-root.
.It Cm !dbg
Specifies that the package should not be built with a debug information
package.
This is the default unless
.Ev DEFAULT_DBG
is set in the environment or
.Xr abuild.conf 5 .
It is typically used on packages that do not generate debug information (such
as pure Python packages) or packages that do not support debug information
packages.
.It Cm !fhs
Specifies that the package violates FHS and installs to a location such as
.Pa /usr/local ,
.Pa /opt ,
or
.Pa /srv .
.It Cm ldpath-recursive
Specifies that
.Xr abuild 1
should use the
.Fl --recursive
argument to
.Xr scanelf 1
when attempting to find shared library (.so) dependencies for the package.
.It Cm libtool
Specifies that the package requires its libtool (.la) files.
They will not be automatically removed by
.Xr abuild 1 .
.It Cm net
Specifies that the package build system requires access to a network.
This is discouraged and an issue should be filed with the package's authors.
.It Cm !strip
Specifies that
.Xr strip 1
should not be run on any of the package's binaries.
This is automatically implied if the -dbg subpackage is enabled, or if you are
using
.Ev DEFAULT_DBG .
.It Cm suid
Specifies that binaries in the package may be installed set-uid.
This is a security risk and it is highly recommended to use capabilities or
process separation instead of set-uid where available.
.It Cm textrels
Specifies that the package's binaries are known to contain relocations against
text segments.
By default,
.Xr abuild 1
will refuse to create such a package because this is a security concern.
.It Cm toolchain
Specifies that the package is part of the base toolchain set and may depend
on packages like
.Li g++ .
.It Cm !tracedeps
Specifies that
.Xr abuild 1
should not automatically populate
.Cm depends
with shared library (.so) or symlink target dependencies.
.El
.Ss Automatic Variables
The following variables are defined for you by
.Xr abuild 1 ,
but may be overridden if necessary.
.Bl -tag -width Ds
.It Cm builddir
Specifies the directory where the source code of the package will be built.
The default value is
.Pa $srcdir/$pkgname-$pkgver
which is appropriate for most source distributions.
If the source tarball does not create a $pkgname-$pkgver directory when it is
unpacked, you must override
.Cm builddir .
.It Cm pkgdir
Specifies the directory where the built files will be installed.
Typically, you will call
.Li make DESTDIR="$pkgdir" install
or similar to install the files.
The default value is
.Pa $startdir/pkg
and you should not modify this variable.
.It Cm srcdir
Specifies the directory where the files specified in
.Cm source
are downloaded and unpacked.
The default value is
.Pa $startdir/src
and you should not need to modify this.
.It Cm startdir
Specifies the directory where the
.Nm
file resides.
.It Cm subpkgdir
Specifies the directory where the subpackage's files should be placed.
This variable is only set inside subpackage functions.
.El
.Ss Special Variables
The following variables are used only in special circumstances, and may be
required or optional depending on their usage and the contents of other
variables.
.Bl -tag -width Ds
.It Cm depends_dev
Specifies the run-time dependencies of the -dev subpackage.
.It Cm depends_libs
Specifies the run-time dependencies of the -libs subpackage.
.It Cm giturl
Specifies the URL of the Git repository to use with
.Cm abuild checkout .
If the default branch of the repository is not desired, a different one may be
specified by appending
.Fl b Ar branch
where
.Cm branch
is the branch to checkout.
.El
.Ss Functions
Functions specified here may be present in any
.Nm
file, but with the exception of
.Cm package ,
are not strictly required.
.Bl -tag -width Ds
.It Cm fetch
This function is called to download the remote files in
.Cm source .
.It Cm unpack
This function unpacks any archives in
.Cm source
to
.Ev srcdir .
.It Cm prepare
Prepares the source in
.Ev srcdir
to be built.
The default
.Cm prepare
function ensures the build directories are set up correctly and applies any
*.patch files specified in
.Cm source .
You must call
.Cm default_prepare
if you write a custom
.Cm prepare
function.
.It Cm build
Compiles the source in
.Ev builddir .
You must implement this function yourself.
If no compilation is required, you may omit it.
.It Cm check
Runs the package's test suite.
This function must be implemented unless
.Li !check
was specified in
.Cm options .
.It Cm package
Installs the package into
.Ev pkgdir .
Note that
.Ev pkgdir
is not created for you; if this package installs no files (for example, a
metapackage), you must use
.Li mkdir -p "$pkgdir"
to skip the package phase.
.El
.Ss Install Scripts
An install script is run when an action is taken on a package by
.Xr apk 8 .
An install script must be written in shell and must have a
.Li #!/bin/sh
interpreter declaration as the first line.
The
.Cm install
variable must contain the install scripts needed by the package.
.Pp
The install script will be run inside the root filesystem where the package is
being installed.
A single argument will be passed to all scripts, which is the version of the
package being currently installed (or deinstalled).
The pre-upgrade and post-upgrade scripts will have an additional second
argument, which specifies the version of the package before the upgrade
process.
.Pp
The different actions that may have install scripts specified are as follows:
.Bl -tag -width Ds
.It Ic $pkgname.pre-install
Executed before the package is installed.
If this script exits with an error (non-zero exit code),
.Xr apk 8
will halt the installation and the package will not be installed.
This install script is typically used to create any users or groups needed as
described in
.Cm pkggroups
and
.Cm pkgusers .
.It Ic $pkgname.post-install
Executed after the package is installed.
If this script exits with an error (non-zero exit code),
.Xr apk 8
will mark the package as broken.
The
.Li apk fix
command will attempt to re-run the post-install script if this occurs.
.It Ic $pkgname.pre-upgrade
Executed before the package is upgraded.
If this script exits with an error (non-zero exit code),
.Xr apk 8
will mark the package as broken.
.It Ic $pkgname.post-upgrade
Executed after the package is upgraded.
If this script exits with an error (non-zero exit code),
.Xr apk 8
will mark the package as broken.
The
.Li apk fix
command will attempt to re-run the post-upgrade script if this occurs.
.It Ic $pkgname.pre-deinstall
Executed before the package is removed from the system.
If this script exits with an error (non-zero exit code),
.Xr apk 8
will not remove the package from the system.
.It Ic $pkgname.post-deinstall
Executed after the package is removed from the system.
Exiting with an error will have no effect.
.El
.Sh IMPLEMENTATION NOTES
Currently,
.Nm
files are sourced as normal shell scripts.  This may change at a later date.
.Sh COMPATIBILITY
The
.Xr abuild 1
utility as distributed by Alpine uses the BusyBox Almquist shell, a part of
.Xr busybox 1
that is currently undocumented.
It is mostly compliant with
.St -p1003.2 ,
with some bash-like extensions.
The
.Xr abuild 1
utility as distributed by Adélie uses the user's preferred /bin/sh, which is
typically
.Xr bash 1 .
.Sh SEE ALSO
SPDX license reference (on the Web at <https://spdx.org/licenses/>),
.Xr abuild 1 ,
.Xr newapkbuild 1 ,
.Xr apk 8 .
.Sh HISTORY
The
.Nm
format and
.Xr abuild 1
utility first appeared in Alpine Linux 1.9.
.Sh AUTHORS
.An Timo Teräs Aq Mt timo.teras@iki.fi
.An Natanael Copa Aq Mt ncopa@alpinelinux.org
.Pp
Documentation:
.An A. Wilcox Aq Mt awilfox@adelielinux.org
.\" .Sh BUGS
.\" if we end up finding bugs that should be documented, put them here.