doc/package/ebuild/eapi/2.docbook

<section id='package-ebuild-eapi-2'>
	<title>EAPI 2</title>
	<section id='package-ebuild-eapi-2-helpers'>
	<title>Helpers</title>
	<section id='package-ebuild-eapi-2-helpers-doman'>
	<title>doman</title>
	<section id='package-ebuild-eapi-2-helpers-doman-language-codes'>
	<title>Recognition of Language Codes in File Names</title>
	<para>
	Language codes in file names are now used for path translation.
	</para>
	<table><title>Man Page Path Translation</title>
	<tgroup cols='2' align='left' >
	<colspec colname='source'/>
	<colspec colname='destination'/>
	<thead>
	<row>
	<entry>Source</entry>
	<entry>Destination</entry>
	</row>
	</thead>
	<tbody>
	<row>
	<entry>foo.1</entry>
	<entry>/usr/share/man/man1/foo.1</entry>
	</row>
	<row>
	<entry>foo.lang.1</entry>
	<entry>/usr/share/man/lang/man1/foo.1</entry>
	</row>
	</tbody>
	</tgroup>
	</table>
	</section>
	</section>
	</section>
	<section id='package-ebuild-eapi-2-metadata'>
	<title>Metadata</title>
	<section id='package-ebuild-eapi-2-metadata-dependencies'>
	<title>Dependencies</title>
	<section id='package-ebuild-eapi-2-metadata-dependencies-blocker-atoms'>
	<title>Blocker Atoms</title>
	<section id='package-ebuild-eapi-2-metadata-dependencies-blocker-atoms-new-meaning'>
	<title>New Meaning for Old Syntax</title>
	<para>
	Blocker atoms which use the previously existing !atom syntax now have
	a slightly different meaning. These blocker atoms indicate that
	conflicting packages may be temporarily installed simultaneously. When
	temporary simultaneous installation of conflicting packages occurs, the
	installation of a newer package may overwrite any colliding files that
	belong to an older package which is explicitly blocked. When such file
	collisions occur, the colliding files cease to belong to the older
	package, and they remain installed after the older package is
	eventually uninstalled. The older package is uninstalled only after
	any newer blocking packages have been merged on top of it.
	</para>
	</section>
	<section id='package-ebuild-eapi-2-metadata-dependencies-blocker-atoms-new-syntax'>
	<title>New !!atom Syntax</title>
	<para>
	A new !!atom syntax is now supported, for use in special cases for which
	temporary simultaneous installation of conflicting packages should not be
	allowed. If a given package happens to be blocked my a mixture of atoms
	consisting of both the !atom and !!atom syntaxes, the !!atom syntax takes
	precedence over the !atom syntax.
	</para>
	</section>
	</section>
	<section id='package-ebuild-eapi-2-metadata-dependencies-use'>
	<title>USE Dependencies</title>
	<section id='package-ebuild-eapi-2-metadata-dependencies-use-unconditional'>
	<title>Unconditional USE Dependencies</title>
	<table><title>Syntax Examples</title>
	<tgroup cols='2' align='left' >
	<colspec colname='example'/>
	<colspec colname='meaning'/>
	<thead>
	<row>
	<entry>Example</entry>
	<entry>Meaning</entry>
	</row>
	</thead>
	<tbody>
	<row>
	<entry>foo[bar]</entry>
	<entry>foo must have bar enabled</entry>
	</row>
	<row>
	<entry>foo[bar,baz]</entry>
	<entry>foo must have both bar and baz enabled</entry>
	</row>
	<row>
	<entry>foo[-bar,baz]</entry>
	<entry>foo must have bar disabled and baz enabled</entry>
	</row>
	</tbody>
	</tgroup>
	</table>
	</section>
	<section id='package-ebuild-eapi-2-metadata-dependencies-use-conditional'>
	<title>Conditional USE Dependencies</title>
	<table><title>Syntax Examples</title>
	<tgroup cols='2' align='left' >
	<colspec colname='compact'/>
	<colspec colname='expanded'/>
	<thead>
	<row>
	<entry>Compact Form</entry>
	<entry>Equivalent Expanded Form</entry>
	</row>
	</thead>
	<tbody>
	<row>
	<entry>foo[bar?]</entry>
	<entry>bar? ( foo[bar]  ) !bar? ( foo       )</entry>
	</row>
	<row>
	<entry>foo[!bar?]</entry>
	<entry>bar? ( foo       ) !bar? ( foo[-bar] )</entry>
	</row>
	<row>
	<entry>foo[bar=]</entry>
	<entry>bar? ( foo[bar]  ) !bar? ( foo[-bar] )</entry>
	</row>
	<row>
	<entry>foo[!bar=]</entry>
	<entry>bar? ( foo[-bar] ) !bar? ( foo[bar]  )</entry>
	</row>
	</tbody>
	</tgroup>
	</table>
	</section>
	</section>
	</section>
	<section id='package-ebuild-eapi-2-metadata-src-uri'>
		<title>SRC_URI</title>
		<section id='package-ebuild-eapi-2-metadata-src-uri-output-file-name-customization'>
			<title>Customization of Output File Names</title>
			<para>
			A new syntax is supported which allows customization of the output
			file name for a given URI. In order to customize the output file
			name, a given URI should be followed by a "->" operator which,
			in turn, should be followed by the desired output file name. As
			usual, all tokens, including the operator and output file name,
			should be separated by whitespace.
			</para>
		</section>
	</section>
	</section>
	<section id='package-ebuild-eapi-2-phases'>
		<title>Phases</title>
		<section id='package-ebuild-eapi-2-phases-src-prepare'>
			<title>New src_prepare Phase Function</title>
			<para>
			A new src_prepare function is called after the src_unpack
			function, with cwd initially set to $S.
			</para>
		</section>
		<section id='package-ebuild-eapi-2-phases-src-configure'>
			<title>New src_configure Phase Function</title>
			<para>
			The configure portion of the src_compile function has been
			split into a separate function which is named src_configure. The
			src_configure function is called in-between the src_prepare and
			src_compile functions.
			</para>
			<programlisting>
src_configure() {
	if [[ -x ${ECONF_SOURCE:-.}/configure ]] ; then
		econf
	fi
}

src_compile() {
	if [ -f Makefile ] || [ -f GNUmakefile ] || [ -f makefile ] ; then
		emake || die "emake failed"
	fi
}
			</programlisting>
		</section>
		<section id='package-ebuild-eapi-2-phases-order'>
			<title>Execution Order of Phase Functions</title>
			<table><title>Execution Order of Phase Functions</title>
				<tgroup cols='1' align='left' >
				<colspec colname='name'/>
				<thead>
				<row>
					<entry>Phase Function Name</entry>
				</row>
				</thead>
				<tbody>
				<row>
					<entry>pkg_setup</entry>
				</row>
				<row>
					<entry>src_unpack</entry>
				</row>
				<row>
					<entry>src_prepare</entry>
				</row>
				<row>
					<entry>src_configure</entry>
				</row>
				<row>
					<entry>src_compile</entry>
				</row>
				<row>
					<entry>src_test</entry>
				</row>
				<row>
					<entry>src_install</entry>
				</row>
				<row>
					<entry>pkg_preinst</entry>
				</row>
				<row>
					<entry>pkg_postinst</entry>
				</row>
				<row>
					<entry>pkg_prerm</entry>
				</row>
				<row>
					<entry>pkg_postrm</entry>
				</row>
				</tbody>
				</tgroup>
			</table>
		</section>
		<section id='package-ebuild-eapi-2-phases-default-functions'>
			<title>Default Phase Functions</title>
			<para>
			The default pkg_nofetch and src_* phase functions are now
			accessible via a function having a name
			that begins with default_ and
			ends with the respective phase function name. For example,
			a call to a function with the name default_src_compile is
			equivalent to a call to the default src_compile
			implementation.
			</para>
			<table><title>Default Phase Functions</title>
				<tgroup cols='1' align='left' >
				<colspec colname='name'/>
				<thead>
				<row>
					<entry>Function Name</entry>
				</row>
				</thead>
				<tbody>
				<row>
					<entry>default_pkg_nofetch</entry>
				</row>
				<row>
					<entry>default_src_unpack</entry>
				</row>
				<row>
					<entry>default_src_prepare</entry>
				</row>
				<row>
					<entry>default_src_configure</entry>
				</row>
				<row>
					<entry>default_src_compile</entry>
				</row>
				<row>
					<entry>default_src_test</entry>
				</row>
				</tbody>
				</tgroup>
			</table>
		</section>
		<section id='package-ebuild-eapi-2-phases-default-function-alias'>
			<title>Default Phase Function Alias</title>
			<para>
			A function named "default" is redefined for each phase so that it
			will call the default_* function corresponding to the current phase.
			For example, a call to the function named "default" during the
			src_compile phase is equivalent to a call to the function named
			default_src_compile.
			</para>
		</section>
	</section>
</section>