mirror of
https://github.com/NixOS/nixpkgs.git
synced 2024-11-25 07:00:43 +00:00
ec5b66eb4a
You can now pass separateDebugInfo = true; to mkDerivation. This causes debug info to be separated from ELF binaries and stored in the "debug" output. The advantage is that it enables installing lean binaries, while still having the ability to make sense of core dumps, etc.
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
|
||
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
|
||
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
|
||
<literal>stdenv</literal> doesn’t do what you need automatically, you
|
||
can easily customise or override the various build phases.</para>
|
||
|
||
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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
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||
in a separate Nix expression from
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||
<filename>pkgs/all-packages.nix</filename>, you need to pass it as a
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||
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
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||
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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||
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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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||
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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>
|
||
|
||
(Note the use of <literal>''</literal>-style string literals, which
|
||
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>
|
||
|
||
<para>While the standard environment provides a generic builder, you
|
||
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
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||
<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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||
|
||
genericBuild
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||
</programlisting>
|
||
|
||
</para>
|
||
|
||
</section>
|
||
|
||
|
||
<section xml:id="sec-tools-of-stdenv"><title>Tools provided by
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||
<literal>stdenv</literal></title>
|
||
|
||
<para>The standard environment provides the following packages:
|
||
|
||
<itemizedlist>
|
||
|
||
<listitem><para>The GNU C Compiler, configured with C and C++
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||
support.</para></listitem>
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||
|
||
<listitem><para>GNU coreutils (contains a few dozen standard Unix
|
||
commands).</para></listitem>
|
||
|
||
<listitem><para>GNU findutils (contains
|
||
<command>find</command>).</para></listitem>
|
||
|
||
<listitem><para>GNU diffutils (contains <command>diff</command>,
|
||
<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>
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||
|
||
<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>
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||
|
||
<listitem><para>The <command>patch</command>
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||
command.</para></listitem>
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||
|
||
</itemizedlist>
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||
|
||
</para>
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||
|
||
<para>On Linux, <literal>stdenv</literal> also includes the
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||
<command>patchelf</command> utility.</para>
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||
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||
</section>
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||
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||
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||
<section xml:id="ssec-stdenv-attributes"><title>Attributes</title>
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||
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||
<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
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||
<filename><replaceable>dir</replaceable>/bin</filename>, if it
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||
exists, is added to the <envar>PATH</envar> environment variable.
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||
Other environment variables are also set up via a pluggable
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||
mechanism. For instance, if <varname>buildInputs</varname>
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||
contains Perl, then the <filename>lib/site_perl</filename>
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||
subdirectory of each input is added to the <envar>PERL5LIB</envar>
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||
environment variable. See <xref linkend="ssec-setup-hooks"/> for
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||
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
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||
<emphasis>this</emphasis> package as a dependency. So if package
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||
Y has <literal>propagatedBuildInputs = [X]</literal>, and package
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||
Z has <literal>buildInputs = [Y]</literal>, then package X will
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||
appear in Z’s build environment automatically.</para></listitem>
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||
</varlistentry>
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||
|
||
|
||
</variablelist>
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||
|
||
</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
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||
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
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||
containing some shell commands to be executed, or by redefining the
|
||
shell function
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||
<varname><replaceable>name</replaceable>Phase</varname>. The former
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||
is convenient to override a phase from the derivation, while the
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||
latter is convenient from a build script.</para>
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||
|
||
|
||
<section xml:id="ssec-controlling-phases"><title>Controlling
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||
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
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||
variable. If it’s not set, the default value is used, which is
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||
<literal>$prePhases unpackPhase patchPhase $preConfigurePhases
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||
configurePhase $preBuildPhases buildPhase checkPhase
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||
$preInstallPhases installPhase fixupPhase $preDistPhases
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||
distPhase $postPhases</literal>.
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||
</para>
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||
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||
<para>Usually, if you just want to add a few phases, it’s more
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||
convenient to set one of the variables below (such as
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<varname>preInstallPhases</varname>), as you then don’t specify
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||
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</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>
|
||
|