mirror of
https://github.com/NixOS/nixpkgs.git
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1258 lines
42 KiB
XML
1258 lines
42 KiB
XML
<chapter xmlns="http://docbook.org/ns/docbook"
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xmlns:xlink="http://www.w3.org/1999/xlink"
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xml:id="chap-stdenv">
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||
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||
<title>The Standard Environment</title>
|
||
|
||
|
||
<para>The standard build environment in the Nix Packages collection
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||
provides an environment for building Unix packages that does a lot of
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||
common build tasks automatically. In fact, for Unix packages that use
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||
the standard <literal>./configure; make; make install</literal> build
|
||
interface, you don’t need to write a build script at all; the standard
|
||
environment does everything automatically. If
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||
<literal>stdenv</literal> doesn’t do what you need automatically, you
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||
can easily customise or override the various build phases.</para>
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||
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||
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||
<section xml:id="sec-using-stdenv"><title>Using
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||
<literal>stdenv</literal></title>
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||
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||
<para>To build a package with the standard environment, you use the
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||
function <varname>stdenv.mkDerivation</varname>, instead of the
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||
primitive built-in function <varname>derivation</varname>, e.g.
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||
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<programlisting>
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stdenv.mkDerivation {
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name = "libfoo-1.2.3";
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||
src = fetchurl {
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||
url = http://example.org/libfoo-1.2.3.tar.bz2;
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md5 = "e1ec107956b6ddcb0b8b0679367e9ac9";
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||
};
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||
}</programlisting>
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||
|
||
(<varname>stdenv</varname> needs to be in scope, so if you write this
|
||
in a separate Nix expression from
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||
<filename>pkgs/all-packages.nix</filename>, you need to pass it as a
|
||
function argument.) Specifying a <varname>name</varname> and a
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||
<varname>src</varname> is the absolute minimum you need to do. Many
|
||
packages have dependencies that are not provided in the standard
|
||
environment. It’s usually sufficient to specify those dependencies in
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||
the <varname>buildInputs</varname> attribute:
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||
|
||
<programlisting>
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||
stdenv.mkDerivation {
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||
name = "libfoo-1.2.3";
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||
...
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buildInputs = [libbar perl ncurses];
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||
}</programlisting>
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||
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||
This attribute ensures that the <filename>bin</filename>
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||
subdirectories of these packages appear in the <envar>PATH</envar>
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||
environment variable during the build, that their
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<filename>include</filename> subdirectories are searched by the C
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||
compiler, and so on. (See <xref linkend="ssec-setup-hooks"/> for
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||
details.)</para>
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||
|
||
<para>Often it is necessary to override or modify some aspect of the
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||
build. To make this easier, the standard environment breaks the
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||
package build into a number of <emphasis>phases</emphasis>, all of
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||
which can be overridden or modified individually: unpacking the
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||
sources, applying patches, configuring, building, and installing.
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||
(There are some others; see <xref linkend="sec-stdenv-phases"/>.)
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||
For instance, a package that doesn’t supply a makefile but instead has
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||
to be compiled “manually” could be handled like this:
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||
|
||
<programlisting>
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||
stdenv.mkDerivation {
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||
name = "fnord-4.5";
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||
...
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buildPhase = ''
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gcc foo.c -o foo
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'';
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installPhase = ''
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mkdir -p $out/bin
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cp foo $out/bin
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'';
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||
}</programlisting>
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||
|
||
(Note the use of <literal>''</literal>-style string literals, which
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||
are very convenient for large multi-line script fragments because they
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||
don’t need escaping of <literal>"</literal> and <literal>\</literal>,
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||
and because indentation is intelligently removed.)</para>
|
||
|
||
<para>There are many other attributes to customise the build. These
|
||
are listed in <xref linkend="ssec-stdenv-attributes"/>.</para>
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||
|
||
<para>While the standard environment provides a generic builder, you
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||
can still supply your own build script:
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||
|
||
<programlisting>
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||
stdenv.mkDerivation {
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||
name = "libfoo-1.2.3";
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||
...
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||
builder = ./builder.sh;
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||
}</programlisting>
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||
|
||
where the builder can do anything it wants, but typically starts with
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||
|
||
<programlisting>
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||
source $stdenv/setup
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||
</programlisting>
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||
|
||
to let <literal>stdenv</literal> set up the environment (e.g., process
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||
the <varname>buildInputs</varname>). If you want, you can still use
|
||
<literal>stdenv</literal>’s generic builder:
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||
|
||
<programlisting>
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||
source $stdenv/setup
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||
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||
buildPhase() {
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||
echo "... this is my custom build phase ..."
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||
gcc foo.c -o foo
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||
}
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||
|
||
installPhase() {
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||
mkdir -p $out/bin
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||
cp foo $out/bin
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||
}
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||
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||
genericBuild
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||
</programlisting>
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||
|
||
</para>
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||
|
||
</section>
|
||
|
||
|
||
<section xml:id="sec-tools-of-stdenv"><title>Tools provided by
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||
<literal>stdenv</literal></title>
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||
|
||
<para>The standard environment provides the following packages:
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||
|
||
<itemizedlist>
|
||
|
||
<listitem><para>The GNU C Compiler, configured with C and C++
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||
support.</para></listitem>
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||
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||
<listitem><para>GNU coreutils (contains a few dozen standard Unix
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||
commands).</para></listitem>
|
||
|
||
<listitem><para>GNU findutils (contains
|
||
<command>find</command>).</para></listitem>
|
||
|
||
<listitem><para>GNU diffutils (contains <command>diff</command>,
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||
<command>cmp</command>).</para></listitem>
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||
|
||
<listitem><para>GNU <command>sed</command>.</para></listitem>
|
||
|
||
<listitem><para>GNU <command>grep</command>.</para></listitem>
|
||
|
||
<listitem><para>GNU <command>awk</command>.</para></listitem>
|
||
|
||
<listitem><para>GNU <command>tar</command>.</para></listitem>
|
||
|
||
<listitem><para><command>gzip</command>, <command>bzip2</command>
|
||
and <command>xz</command>.</para></listitem>
|
||
|
||
<listitem><para>GNU Make. It has been patched to provide
|
||
<quote>nested</quote> output that can be fed into the
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||
<command>nix-log2xml</command> command and
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||
<command>log2html</command> stylesheet to create a structured,
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||
readable output of the build steps performed by
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||
Make.</para></listitem>
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||
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||
<listitem><para>Bash. This is the shell used for all builders in
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||
the Nix Packages collection. Not using <command>/bin/sh</command>
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||
removes a large source of portability problems.</para></listitem>
|
||
|
||
<listitem><para>The <command>patch</command>
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||
command.</para></listitem>
|
||
|
||
</itemizedlist>
|
||
|
||
</para>
|
||
|
||
<para>On Linux, <literal>stdenv</literal> also includes the
|
||
<command>patchelf</command> utility.</para>
|
||
|
||
</section>
|
||
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||
|
||
<section xml:id="ssec-stdenv-attributes"><title>Attributes</title>
|
||
|
||
<variablelist>
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||
<title>Variables affecting <literal>stdenv</literal>
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||
initialisation</title>
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||
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||
<varlistentry>
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||
<term><varname>NIX_DEBUG</varname></term>
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||
<listitem><para>If set, <literal>stdenv</literal> will print some
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||
debug information during the build. In particular, the
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||
<command>gcc</command> and <command>ld</command> wrapper scripts
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||
will print out the complete command line passed to the wrapped
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||
tools.</para></listitem>
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||
</varlistentry>
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||
|
||
<varlistentry>
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||
<term><varname>buildInputs</varname></term>
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||
<listitem><para>A list of dependencies used by
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||
<literal>stdenv</literal> to set up the environment for the build.
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||
For each dependency <replaceable>dir</replaceable>, the directory
|
||
<filename><replaceable>dir</replaceable>/bin</filename>, if it
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||
exists, is added to the <envar>PATH</envar> environment variable.
|
||
Other environment variables are also set up via a pluggable
|
||
mechanism. For instance, if <varname>buildInputs</varname>
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||
contains Perl, then the <filename>lib/site_perl</filename>
|
||
subdirectory of each input is added to the <envar>PERL5LIB</envar>
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||
environment variable. See <xref linkend="ssec-setup-hooks"/> for
|
||
details.</para></listitem>
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||
</varlistentry>
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||
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||
<varlistentry>
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||
<term><varname>propagatedBuildInputs</varname></term>
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||
<listitem><para>Like <varname>buildInputs</varname>, but these
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||
dependencies are <emphasis>propagated</emphasis>: that is, the
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||
dependencies listed here are added to the
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||
<varname>buildInputs</varname> of any package that uses
|
||
<emphasis>this</emphasis> package as a dependency. So if package
|
||
Y has <literal>propagatedBuildInputs = [X]</literal>, and package
|
||
Z has <literal>buildInputs = [Y]</literal>, then package X will
|
||
appear in Z’s build environment automatically.</para></listitem>
|
||
</varlistentry>
|
||
|
||
|
||
</variablelist>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="sec-stdenv-phases"><title>Phases</title>
|
||
|
||
<para>The generic builder has a number of <emphasis>phases</emphasis>.
|
||
Package builds are split into phases to make it easier to override
|
||
specific parts of the build (e.g., unpacking the sources or installing
|
||
the binaries). Furthermore, it allows a nicer presentation of build
|
||
logs in the Nix build farm.</para>
|
||
|
||
<para>Each phase can be overridden in its entirety either by setting
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||
the environment variable
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||
<varname><replaceable>name</replaceable>Phase</varname> to a string
|
||
containing some shell commands to be executed, or by redefining the
|
||
shell function
|
||
<varname><replaceable>name</replaceable>Phase</varname>. The former
|
||
is convenient to override a phase from the derivation, while the
|
||
latter is convenient from a build script.</para>
|
||
|
||
|
||
<section xml:id="ssec-controlling-phases"><title>Controlling
|
||
phases</title>
|
||
|
||
<para>There are a number of variables that control what phases are
|
||
executed and in what order:
|
||
|
||
<variablelist>
|
||
<title>Variables affecting phase control</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>phases</varname></term>
|
||
<listitem>
|
||
<para>Specifies the phases. You can change the order in which
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||
phases are executed, or add new phases, by setting this
|
||
variable. If it’s not set, the default value is used, which is
|
||
<literal>$prePhases unpackPhase patchPhase $preConfigurePhases
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||
configurePhase $preBuildPhases buildPhase checkPhase
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||
$preInstallPhases installPhase fixupPhase $preDistPhases
|
||
distPhase $postPhases</literal>.
|
||
</para>
|
||
|
||
<para>Usually, if you just want to add a few phases, it’s more
|
||
convenient to set one of the variables below (such as
|
||
<varname>preInstallPhases</varname>), as you then don’t specify
|
||
all the normal phases.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>prePhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed before any of the default phases.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preConfigurePhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed just before the configure phase.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preBuildPhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed just before the build phase.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preInstallPhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed just before the install phase.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preFixupPhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed just before the fixup phase.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preDistPhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed just before the distribution phase.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postPhases</varname></term>
|
||
<listitem>
|
||
<para>Additional phases executed after any of the default
|
||
phases.</para>
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</para>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-unpack-phase"><title>The unpack phase</title>
|
||
|
||
<para>The unpack phase is responsible for unpacking the source code of
|
||
the package. The default implementation of
|
||
<function>unpackPhase</function> unpacks the source files listed in
|
||
the <envar>src</envar> environment variable to the current directory.
|
||
It supports the following files by default:
|
||
|
||
<variablelist>
|
||
|
||
<varlistentry>
|
||
<term>Tar files</term>
|
||
<listitem><para>These can optionally be compressed using
|
||
<command>gzip</command> (<filename>.tar.gz</filename>,
|
||
<filename>.tgz</filename> or <filename>.tar.Z</filename>),
|
||
<command>bzip2</command> (<filename>.tar.bz2</filename> or
|
||
<filename>.tbz2</filename>) or <command>xz</command>
|
||
(<filename>.tar.xz</filename> or
|
||
<filename>.tar.lzma</filename>).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Zip files</term>
|
||
<listitem><para>Zip files are unpacked using
|
||
<command>unzip</command>. However, <command>unzip</command> is
|
||
not in the standard environment, so you should add it to
|
||
<varname>buildInputs</varname> yourself.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Directories in the Nix store</term>
|
||
<listitem><para>These are simply copied to the current directory.
|
||
The hash part of the file name is stripped,
|
||
e.g. <filename>/nix/store/1wydxgby13cz...-my-sources</filename>
|
||
would be copied to
|
||
<filename>my-sources</filename>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
Additional file types can be supported by setting the
|
||
<varname>unpackCmd</varname> variable (see below).</para>
|
||
|
||
<para></para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the unpack phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>srcs</varname> / <varname>src</varname></term>
|
||
<listitem><para>The list of source files or directories to be
|
||
unpacked or copied. One of these must be set.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>sourceRoot</varname></term>
|
||
<listitem><para>After running <function>unpackPhase</function>,
|
||
the generic builder changes the current directory to the directory
|
||
created by unpacking the sources. If there are multiple source
|
||
directories, you should set <varname>sourceRoot</varname> to the
|
||
name of the intended directory.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>setSourceRoot</varname></term>
|
||
<listitem><para>Alternatively to setting
|
||
<varname>sourceRoot</varname>, you can set
|
||
<varname>setSourceRoot</varname> to a shell command to be
|
||
evaluated by the unpack phase after the sources have been
|
||
unpacked. This command must set
|
||
<varname>sourceRoot</varname>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preUnpack</varname></term>
|
||
<listitem><para>Hook executed at the start of the unpack
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postUnpack</varname></term>
|
||
<listitem><para>Hook executed at the end of the unpack
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontMakeSourcesWritable</varname></term>
|
||
<listitem><para>If set to <literal>1</literal>, the unpacked
|
||
sources are <emphasis>not</emphasis> made
|
||
writable. By default, they are made writable to prevent problems
|
||
with read-only sources. For example, copied store directories
|
||
would be read-only without this.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>unpackCmd</varname></term>
|
||
<listitem><para>The unpack phase evaluates the string
|
||
<literal>$unpackCmd</literal> for any unrecognised file. The path
|
||
to the current source file is contained in the
|
||
<varname>curSrc</varname> variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-patch-phase"><title>The patch phase</title>
|
||
|
||
<para>The patch phase applies the list of patches defined in the
|
||
<varname>patches</varname> variable.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the patch phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>patches</varname></term>
|
||
<listitem><para>The list of patches. They must be in the format
|
||
accepted by the <command>patch</command> command, and may
|
||
optionally be compressed using <command>gzip</command>
|
||
(<filename>.gz</filename>), <command>bzip2</command>
|
||
(<filename>.bz2</filename>) or <command>xz</command>
|
||
(<filename>.xz</filename>).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>patchFlags</varname></term>
|
||
<listitem><para>Flags to be passed to <command>patch</command>.
|
||
If not set, the argument <option>-p1</option> is used, which
|
||
causes the leading directory component to be stripped from the
|
||
file names in each patch.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>prePatch</varname></term>
|
||
<listitem><para>Hook executed at the start of the patch
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postPatch</varname></term>
|
||
<listitem><para>Hook executed at the end of the patch
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-configure-phase"><title>The configure phase</title>
|
||
|
||
<para>The configure phase prepares the source tree for building. The
|
||
default <function>configurePhase</function> runs
|
||
<filename>./configure</filename> (typically an Autoconf-generated
|
||
script) if it exists.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the configure phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>configureScript</varname></term>
|
||
<listitem><para>The name of the configure script. It defaults to
|
||
<filename>./configure</filename> if it exists; otherwise, the
|
||
configure phase is skipped. This can actually be a command (like
|
||
<literal>perl ./Configure.pl</literal>).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>configureFlags</varname></term>
|
||
<listitem><para>Additional arguments passed to the configure
|
||
script.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>configureFlagsArray</varname></term>
|
||
<listitem><para>A shell array containing additional arguments
|
||
passed to the configure script. You must use this instead of
|
||
<varname>configureFlags</varname> if the arguments contain
|
||
spaces.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontAddPrefix</varname></term>
|
||
<listitem><para>By default, the flag
|
||
<literal>--prefix=$prefix</literal> is added to the configure
|
||
flags. If this is undesirable, set this variable to
|
||
true.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>prefix</varname></term>
|
||
<listitem><para>The prefix under which the package must be
|
||
installed, passed via the <option>--prefix</option> option to the
|
||
configure script. It defaults to
|
||
<option>$out</option>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontAddDisableDepTrack</varname></term>
|
||
<listitem><para>By default, the flag
|
||
<literal>--disable-dependency-tracking</literal> is added to the
|
||
configure flags to speed up Automake-based builds. If this is
|
||
undesirable, set this variable to true.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontFixLibtool</varname></term>
|
||
<listitem><para>By default, the configure phase applies some
|
||
special hackery to all files called <filename>ltmain.sh</filename>
|
||
before running the configure script in order to improve the purity
|
||
of Libtool-based packages<footnote><para>It clears the
|
||
<varname>sys_lib_<replaceable>*</replaceable>search_path</varname>
|
||
variables in the Libtool script to prevent Libtool from using
|
||
libraries in <filename>/usr/lib</filename> and
|
||
such.</para></footnote>. If this is undesirable, set this
|
||
variable to true.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontDisableStatic</varname></term>
|
||
<listitem><para>By default, when the configure script has
|
||
<option>--enable-static</option>, the option
|
||
<option>--disable-static</option> is added to the configure flags.</para>
|
||
<para>If this is undesirable, set this variable to
|
||
true.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preConfigure</varname></term>
|
||
<listitem><para>Hook executed at the start of the configure
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postConfigure</varname></term>
|
||
<listitem><para>Hook executed at the end of the configure
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="build-phase"><title>The build phase</title>
|
||
|
||
<para>The build phase is responsible for actually building the package
|
||
(e.g. compiling it). The default <function>buildPhase</function>
|
||
simply calls <command>make</command> if a file named
|
||
<filename>Makefile</filename>, <filename>makefile</filename> or
|
||
<filename>GNUmakefile</filename> exists in the current directory (or
|
||
the <varname>makefile</varname> is explicitly set); otherwise it does
|
||
nothing.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the build phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontBuild</varname></term>
|
||
<listitem><para>Set to true to skip the build phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>makefile</varname></term>
|
||
<listitem><para>The file name of the Makefile.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>makeFlags</varname></term>
|
||
<listitem><para>Additional flags passed to
|
||
<command>make</command>. These flags are also used by the default
|
||
install and check phase. For setting make flags specific to the
|
||
build phase, use <varname>buildFlags</varname> (see
|
||
below).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>makeFlagsArray</varname></term>
|
||
<listitem><para>A shell array containing additional arguments
|
||
passed to <command>make</command>. You must use this instead of
|
||
<varname>makeFlags</varname> if the arguments contain
|
||
spaces, e.g.
|
||
|
||
<programlisting>
|
||
makeFlagsArray=(CFLAGS="-O0 -g" LDFLAGS="-lfoo -lbar")
|
||
</programlisting>
|
||
|
||
Note that shell arrays cannot be passed through environment
|
||
variables, so you cannot set <varname>makeFlagsArray</varname> in
|
||
a derivation attribute (because those are passed through
|
||
environment variables): you have to define them in shell
|
||
code.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>buildFlags</varname> / <varname>buildFlagsArray</varname></term>
|
||
<listitem><para>Additional flags passed to
|
||
<command>make</command>. Like <varname>makeFlags</varname> and
|
||
<varname>makeFlagsArray</varname>, but only used by the build
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preBuild</varname></term>
|
||
<listitem><para>Hook executed at the start of the build
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postBuild</varname></term>
|
||
<listitem><para>Hook executed at the end of the build
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
|
||
<para>
|
||
You can set flags for <command>make</command> through the
|
||
<varname>makeFlags</varname> variable.</para>
|
||
|
||
<para>Before and after running <command>make</command>, the hooks
|
||
<varname>preBuild</varname> and <varname>postBuild</varname> are
|
||
called, respectively.</para>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-check-phase"><title>The check phase</title>
|
||
|
||
<para>The check phase checks whether the package was built correctly
|
||
by running its test suite. The default
|
||
<function>checkPhase</function> calls <command>make check</command>,
|
||
but only if the <varname>doCheck</varname> variable is enabled.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the check phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>doCheck</varname></term>
|
||
<listitem><para>If set to a non-empty string, the check phase is
|
||
executed, otherwise it is skipped (default). Thus you should set
|
||
|
||
<programlisting>
|
||
doCheck = true;</programlisting>
|
||
|
||
in the derivation to enable checks.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>makeFlags</varname> /
|
||
<varname>makeFlagsArray</varname> /
|
||
<varname>makefile</varname></term>
|
||
<listitem><para>See the build phase for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>checkTarget</varname></term>
|
||
<listitem><para>The make target that runs the tests. Defaults to
|
||
<literal>check</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>checkFlags</varname> / <varname>checkFlagsArray</varname></term>
|
||
<listitem><para>Additional flags passed to
|
||
<command>make</command>. Like <varname>makeFlags</varname> and
|
||
<varname>makeFlagsArray</varname>, but only used by the check
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preCheck</varname></term>
|
||
<listitem><para>Hook executed at the start of the check
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postCheck</varname></term>
|
||
<listitem><para>Hook executed at the end of the check
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-install-phase"><title>The install phase</title>
|
||
|
||
<para>The install phase is responsible for installing the package in
|
||
the Nix store under <envar>out</envar>. The default
|
||
<function>installPhase</function> creates the directory
|
||
<literal>$out</literal> and calls <command>make
|
||
install</command>.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the install phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>makeFlags</varname> /
|
||
<varname>makeFlagsArray</varname> /
|
||
<varname>makefile</varname></term>
|
||
<listitem><para>See the build phase for details.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>installTargets</varname></term>
|
||
<listitem><para>The make targets that perform the installation.
|
||
Defaults to <literal>install</literal>. Example:
|
||
|
||
<programlisting>
|
||
installTargets = "install-bin install-doc";</programlisting>
|
||
|
||
</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>installFlags</varname> / <varname>installFlagsArray</varname></term>
|
||
<listitem><para>Additional flags passed to
|
||
<command>make</command>. Like <varname>makeFlags</varname> and
|
||
<varname>makeFlagsArray</varname>, but only used by the install
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preInstall</varname></term>
|
||
<listitem><para>Hook executed at the start of the install
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postInstall</varname></term>
|
||
<listitem><para>Hook executed at the end of the install
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-fixup-phase"><title>The fixup phase</title>
|
||
|
||
<para>The fixup phase performs some (Nix-specific) post-processing
|
||
actions on the files installed under <filename>$out</filename> by the
|
||
install phase. The default <function>fixupPhase</function> does the
|
||
following:
|
||
|
||
<itemizedlist>
|
||
|
||
<listitem><para>It moves the <filename>man/</filename>,
|
||
<filename>doc/</filename> and <filename>info/</filename>
|
||
subdirectories of <envar>$out</envar> to
|
||
<filename>share/</filename>.</para></listitem>
|
||
|
||
<listitem><para>It strips libraries and executables of debug
|
||
information.</para></listitem>
|
||
|
||
<listitem><para>On Linux, it applies the <command>patchelf</command>
|
||
command to ELF executables and libraries to remove unused
|
||
directories from the <literal>RPATH</literal> in order to prevent
|
||
unnecessary runtime dependencies.</para></listitem>
|
||
|
||
<listitem><para>It rewrites the interpreter paths of shell scripts
|
||
to paths found in <envar>PATH</envar>. E.g.,
|
||
<filename>/usr/bin/perl</filename> will be rewritten to
|
||
<filename>/nix/store/<replaceable>some-perl</replaceable>/bin/perl</filename>
|
||
found in <envar>PATH</envar>.</para></listitem>
|
||
|
||
</itemizedlist>
|
||
|
||
</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the fixup phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontStrip</varname></term>
|
||
<listitem><para>If set, libraries and executables are not
|
||
stripped. By default, they are.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontMoveSbin</varname></term>
|
||
<listitem><para>If set, files in <filename>$out/sbin</filename> are not moved
|
||
to <filename>$out/bin</filename>. By default, they are.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>stripAllList</varname></term>
|
||
<listitem><para>List of directories to search for libraries and
|
||
executables from which <emphasis>all</emphasis> symbols should be
|
||
stripped. By default, it’s empty. Stripping all symbols is
|
||
risky, since it may remove not just debug symbols but also ELF
|
||
information necessary for normal execution.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>stripAllFlags</varname></term>
|
||
<listitem><para>Flags passed to the <command>strip</command>
|
||
command applied to the files in the directories listed in
|
||
<varname>stripAllList</varname>. Defaults to <option>-s</option>
|
||
(i.e. <option>--strip-all</option>).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>stripDebugList</varname></term>
|
||
<listitem><para>List of directories to search for libraries and
|
||
executables from which only debugging-related symbols should be
|
||
stripped. It defaults to <literal>lib bin
|
||
sbin</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>stripDebugFlags</varname></term>
|
||
<listitem><para>Flags passed to the <command>strip</command>
|
||
command applied to the files in the directories listed in
|
||
<varname>stripDebugList</varname>. Defaults to
|
||
<option>-S</option>
|
||
(i.e. <option>--strip-debug</option>).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontPatchELF</varname></term>
|
||
<listitem><para>If set, the <command>patchelf</command> command is
|
||
not used to remove unnecessary <literal>RPATH</literal> entries.
|
||
Only applies to Linux.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontPatchShebangs</varname></term>
|
||
<listitem><para>If set, scripts starting with
|
||
<literal>#!</literal> do not have their interpreter paths
|
||
rewritten to paths in the Nix store.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>forceShare</varname></term>
|
||
<listitem><para>The list of directories that must be moved from
|
||
<filename>$out</filename> to <filename>$out/share</filename>.
|
||
Defaults to <literal>man doc info</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>setupHook</varname></term>
|
||
<listitem><para>A package can export a <link
|
||
linkend="ssec-setup-hooks">setup hook</link> by setting this
|
||
variable. The setup hook, if defined, is copied to
|
||
<filename>$out/nix-support/setup-hook</filename>. Environment
|
||
variables are then substituted in it using <function
|
||
linkend="fun-substituteAll">substituteAll</function>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preFixup</varname></term>
|
||
<listitem><para>Hook executed at the start of the fixup
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postFixup</varname></term>
|
||
<listitem><para>Hook executed at the end of the fixup
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>separateDebugInfo</varname></term>
|
||
<listitem><para>If set to <literal>true</literal>, the standard
|
||
environment will enable debug information in C/C++ builds. After
|
||
installation, the debug information will be separated from the
|
||
executables and stored in the output named
|
||
<literal>debug</literal>. (This output is enabled automatically;
|
||
you don’t need to set the <varname>outputs</varname> attribute
|
||
explicitly.) To be precise, the debug information is stored in
|
||
<filename><replaceable>debug</replaceable>/lib/debug/.build-id/<replaceable>XX</replaceable>/<replaceable>YYYY…</replaceable></filename>,
|
||
where <replaceable>XXYYYY…</replaceable> is the <replaceable>build
|
||
ID</replaceable> of the binary — a SHA-1 hash of the contents of
|
||
the binary. Debuggers like GDB use the build ID to look up the
|
||
separated debug information.</para>
|
||
|
||
<para>For example, with GDB, you can add
|
||
|
||
<programlisting>
|
||
set debug-file-directory ~/.nix-profile/lib/debug
|
||
</programlisting>
|
||
|
||
to <filename>~/.gdbinit</filename>. GDB will then be able to find
|
||
debug information installed via <literal>nix-env
|
||
-i</literal>.</para>
|
||
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-distribution-phase"><title>The distribution
|
||
phase</title>
|
||
|
||
<para>The distribution phase is intended to produce a source
|
||
distribution of the package. The default
|
||
<function>distPhase</function> first calls <command>make
|
||
dist</command>, then it copies the resulting source tarballs to
|
||
<filename>$out/tarballs/</filename>. This phase is only executed if
|
||
the attribute <varname>doDist</varname> is set.</para>
|
||
|
||
<variablelist>
|
||
<title>Variables controlling the distribution phase</title>
|
||
|
||
<varlistentry>
|
||
<term><varname>distTarget</varname></term>
|
||
<listitem><para>The make target that produces the distribution.
|
||
Defaults to <literal>dist</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>distFlags</varname> / <varname>distFlagsArray</varname></term>
|
||
<listitem><para>Additional flags passed to
|
||
<command>make</command>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>tarballs</varname></term>
|
||
<listitem><para>The names of the source distribution files to be
|
||
copied to <filename>$out/tarballs/</filename>. It can contain
|
||
shell wildcards. The default is
|
||
<filename>*.tar.gz</filename>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>dontCopyDist</varname></term>
|
||
<listitem><para>If set, no files are copied to
|
||
<filename>$out/tarballs/</filename>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>preDist</varname></term>
|
||
<listitem><para>Hook executed at the start of the distribution
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><varname>postDist</varname></term>
|
||
<listitem><para>Hook executed at the end of the distribution
|
||
phase.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
|
||
</section>
|
||
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-stdenv-functions"><title>Shell functions</title>
|
||
|
||
<para>The standard environment provides a number of useful
|
||
functions.</para>
|
||
|
||
<variablelist>
|
||
|
||
|
||
<varlistentry xml:id='fun-substitute'>
|
||
<term><function>substitute</function>
|
||
<replaceable>infile</replaceable>
|
||
<replaceable>outfile</replaceable>
|
||
<replaceable>subs</replaceable></term>
|
||
|
||
<listitem>
|
||
<para>Performs string substitution on the contents of
|
||
<replaceable>infile</replaceable>, writing the result to
|
||
<replaceable>outfile</replaceable>. The substitutions in
|
||
<replaceable>subs</replaceable> are of the following form:
|
||
|
||
<variablelist>
|
||
<varlistentry>
|
||
<term><option>--replace</option>
|
||
<replaceable>s1</replaceable>
|
||
<replaceable>s2</replaceable></term>
|
||
<listitem><para>Replace every occurence of the string
|
||
<replaceable>s1</replaceable> by
|
||
<replaceable>s2</replaceable>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--subst-var</option>
|
||
<replaceable>varName</replaceable></term>
|
||
<listitem><para>Replace every occurence of
|
||
<literal>@<replaceable>varName</replaceable>@</literal> by
|
||
the contents of the environment variable
|
||
<replaceable>varName</replaceable>. This is useful for
|
||
generating files from templates, using
|
||
<literal>@<replaceable>...</replaceable>@</literal> in the
|
||
template as placeholders.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term><option>--subst-var-by</option>
|
||
<replaceable>varName</replaceable>
|
||
<replaceable>s</replaceable></term>
|
||
<listitem><para>Replace every occurence of
|
||
<literal>@<replaceable>varName</replaceable>@</literal> by
|
||
the string <replaceable>s</replaceable>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</para>
|
||
|
||
<para>Example:
|
||
|
||
<programlisting>
|
||
substitute ./foo.in ./foo.out \
|
||
--replace /usr/bin/bar $bar/bin/bar \
|
||
--replace "a string containing spaces" "some other text" \
|
||
--subst-var someVar
|
||
</programlisting>
|
||
|
||
</para>
|
||
|
||
<para><function>substitute</function> is implemented using the
|
||
<command
|
||
xlink:href="http://replace.richardlloyd.org.uk/">replace</command>
|
||
command. Unlike with the <command>sed</command> command, you
|
||
don’t have to worry about escaping special characters. It
|
||
supports performing substitutions on binary files (such as
|
||
executables), though there you’ll probably want to make sure
|
||
that the replacement string is as long as the replaced
|
||
string.</para>
|
||
|
||
</listitem>
|
||
</varlistentry>
|
||
|
||
|
||
<varlistentry xml:id='fun-substituteInPlace'>
|
||
<term><function>substituteInPlace</function>
|
||
<replaceable>file</replaceable>
|
||
<replaceable>subs</replaceable></term>
|
||
<listitem><para>Like <function>substitute</function>, but performs
|
||
the substitutions in place on the file
|
||
<replaceable>file</replaceable>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
|
||
<varlistentry xml:id='fun-substituteAll'>
|
||
<term><function>substituteAll</function>
|
||
<replaceable>infile</replaceable>
|
||
<replaceable>outfile</replaceable></term>
|
||
<listitem><para>Replaces every occurence of
|
||
<literal>@<replaceable>varName</replaceable>@</literal>, where
|
||
<replaceable>varName</replaceable> is any environment variable, in
|
||
<replaceable>infile</replaceable>, writing the result to
|
||
<replaceable>outfile</replaceable>. For instance, if
|
||
<replaceable>infile</replaceable> has the contents
|
||
|
||
<programlisting>
|
||
#! @bash@/bin/sh
|
||
PATH=@coreutils@/bin
|
||
echo @foo@
|
||
</programlisting>
|
||
|
||
and the environment contains
|
||
<literal>bash=/nix/store/bmwp0q28cf21...-bash-3.2-p39</literal>
|
||
and
|
||
<literal>coreutils=/nix/store/68afga4khv0w...-coreutils-6.12</literal>,
|
||
but does not contain the variable <varname>foo</varname>, then the
|
||
output will be
|
||
|
||
<programlisting>
|
||
#! /nix/store/bmwp0q28cf21...-bash-3.2-p39/bin/sh
|
||
PATH=/nix/store/68afga4khv0w...-coreutils-6.12/bin
|
||
echo @foo@
|
||
</programlisting>
|
||
|
||
That is, no substitution is performed for undefined variables.</para></listitem>
|
||
</varlistentry>
|
||
|
||
|
||
<varlistentry xml:id='fun-substituteAllInPlace'>
|
||
<term><function>substituteAllInPlace</function>
|
||
<replaceable>file</replaceable></term>
|
||
<listitem><para>Like <function>substituteAll</function>, but performs
|
||
the substitutions in place on the file
|
||
<replaceable>file</replaceable>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
|
||
<varlistentry xml:id='fun-stripHash'>
|
||
<term><function>stripHash</function>
|
||
<replaceable>path</replaceable></term>
|
||
<listitem><para>Strips the directory and hash part of a store
|
||
path, and prints (on standard output) only the name part. For
|
||
instance, <literal>stripHash
|
||
/nix/store/68afga4khv0w...-coreutils-6.12</literal> print
|
||
<literal>coreutils-6.12</literal>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
|
||
</variablelist>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="ssec-setup-hooks"><title>Package setup hooks</title>
|
||
|
||
<para>The following packages provide a setup hook:
|
||
|
||
<variablelist>
|
||
|
||
<varlistentry>
|
||
<term>GCC wrapper</term>
|
||
<listitem><para>Adds the <filename>include</filename> subdirectory
|
||
of each build input to the <envar>NIX_CFLAGS_COMPILE</envar>
|
||
environment variable, and the <filename>lib</filename> and
|
||
<filename>lib64</filename> subdirectories to
|
||
<envar>NIX_LDFLAGS</envar>.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Perl</term>
|
||
<listitem><para>Adds the <filename>lib/site_perl</filename> subdirectory
|
||
of each build input to the <envar>PERL5LIB</envar>
|
||
environment variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Python</term>
|
||
<listitem><para>Adds the
|
||
<filename>lib/${python.libPrefix}/site-packages</filename> subdirectory of
|
||
each build input to the <envar>PYTHONPATH</envar> environment
|
||
variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>pkg-config</term>
|
||
<listitem><para>Adds the <filename>lib/pkgconfig</filename> and
|
||
<filename>share/pkgconfig</filename> subdirectories of each
|
||
build input to the <envar>PKG_CONFIG_PATH</envar> environment
|
||
variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Automake</term>
|
||
<listitem><para>Adds the <filename>share/aclocal</filename>
|
||
subdirectory of each build input to the <envar>ACLOCAL_PATH</envar>
|
||
environment variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>libxml2</term>
|
||
<listitem><para>Adds every file named
|
||
<filename>catalog.xml</filename> found under the
|
||
<filename>xml/dtd</filename> and <filename>xml/xsl</filename>
|
||
subdirectories of each build input to the
|
||
<envar>XML_CATALOG_FILES</envar> environment
|
||
variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>teTeX / TeX Live</term>
|
||
<listitem><para>Adds the <filename>share/texmf-nix</filename>
|
||
subdirectory of each build input to the <envar>TEXINPUTS</envar>
|
||
environment variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>Qt 4</term>
|
||
<listitem><para>Sets the <envar>QTDIR</envar> environment variable
|
||
to Qt’s path.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>gdk-pixbuf</term>
|
||
<listitem><para>Exports <envar>GDK_PIXBUF_MODULE_FILE</envar>
|
||
environment variable the the builder. Add librsvg package
|
||
to <varname>buildInputs</varname> to get svg support.</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>GHC</term>
|
||
<listitem><para>Creates a temporary package database and registers
|
||
every Haskell build input in it (TODO: how?).</para></listitem>
|
||
</varlistentry>
|
||
|
||
<varlistentry>
|
||
<term>GStreamer</term>
|
||
<listitem><para>Adds the
|
||
GStreamer plugins subdirectory of
|
||
each build input to the <envar>GST_PLUGIN_SYSTEM_PATH_1_0</envar> or
|
||
<envar>GST_PLUGIN_SYSTEM_PATH</envar> environment variable.</para></listitem>
|
||
</varlistentry>
|
||
|
||
</variablelist>
|
||
|
||
</para>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="sec-purity-in-nixpkgs"><title>Purity in Nixpkgs</title>
|
||
|
||
<para>[measures taken to prevent dependencies on packages outside the
|
||
store, and what you can do to prevent them]</para>
|
||
|
||
<para>GCC doesn't search in locations such as
|
||
<filename>/usr/include</filename>. In fact, attempts to add such
|
||
directories through the <option>-I</option> flag are filtered out.
|
||
Likewise, the linker (from GNU binutils) doesn't search in standard
|
||
locations such as <filename>/usr/lib</filename>. Programs built on
|
||
Linux are linked against a GNU C Library that likewise doesn't search
|
||
in the default system locations.</para>
|
||
|
||
</section>
|
||
|
||
|
||
</chapter>
|
||
|