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12     <title>GLEP 22 -- New "keyword" system to incorporate various userlands/kernels/archs</title>
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27     <div class="document">
28     <table class="rfc2822 field-list" frame="void" rules="none">
29     <col class="field-name" />
30     <col class="field-body" />
31     <tbody valign="top">
32     <tr class="field"><th class="field-name">GLEP:</th><td class="field-body">22</td>
33     </tr>
34     <tr class="field"><th class="field-name">Title:</th><td class="field-body">New &quot;keyword&quot; system to incorporate various userlands/kernels/archs</td>
35     </tr>
36 g2boojum 1.3 <tr class="field"><th class="field-name">Version:</th><td class="field-body">1.4</td>
37 g2boojum 1.1 </tr>
38 g2boojum 1.3 <tr class="field"><th class="field-name">Last-Modified:</th><td class="field-body"><a class="reference" href="http://www.gentoo.org/cgi-bin/viewcvs.cgi/xml/htdocs/proj/en/glep/glep-0022.txt?cvsroot=gentoo">2004/06/06 00:41:40</a></td>
39 g2boojum 1.1 </tr>
40     <tr class="field"><th class="field-name">Author:</th><td class="field-body">Grant Goodyear &lt;g2boojum&#32;&#97;t&#32;gentoo.org&gt;</td>
41     </tr>
42 g2boojum 1.3 <tr class="field"><th class="field-name">Status:</th><td class="field-body">Draft</td>
43 g2boojum 1.1 </tr>
44     <tr class="field"><th class="field-name">Type:</th><td class="field-body">Standards Track</td>
45     </tr>
46     <tr class="field"><th class="field-name">Content-Type:</th><td class="field-body"><a class="reference" href="glep-0002.html">text/x-rst</a></td>
47     </tr>
48     <tr class="field"><th class="field-name">Created:</th><td class="field-body">6-Mar-2004</td>
49     </tr>
50 g2boojum 1.3 <tr class="field"><th class="field-name">Post-History:</th><td class="field-body">6-Mar-2004, 5-Jun-2004</td>
51 g2boojum 1.1 </tr>
52     </tbody>
53     </table>
54     <hr />
55     <div class="contents topic" id="contents">
56     <p class="topic-title"><a name="contents">Contents</a></p>
57     <ul class="simple">
58 g2boojum 1.2 <li><a class="reference" href="#status" id="id14" name="id14">Status</a></li>
59     <li><a class="reference" href="#credits" id="id15" name="id15">Credits</a></li>
60     <li><a class="reference" href="#abstract" id="id16" name="id16">Abstract</a></li>
61     <li><a class="reference" href="#motivation" id="id17" name="id17">Motivation</a></li>
62     <li><a class="reference" href="#specification" id="id18" name="id18">Specification</a><ul>
63 g2boojum 1.3 <li><a class="reference" href="#keyword-fragments" id="id19" name="id19">Keyword Fragments</a></li>
64 g2boojum 1.2 <li><a class="reference" href="#reasonable-defaults" id="id20" name="id20">Reasonable Defaults</a></li>
65 g2boojum 1.3 <li><a class="reference" href="#ebuild-keyword-database" id="id21" name="id21">Ebuild Keyword Database?</a></li>
66     <li><a class="reference" href="#profiles" id="id22" name="id22">Profiles</a></li>
67 g2boojum 1.1 </ul>
68     </li>
69 g2boojum 1.3 <li><a class="reference" href="#rationale" id="id23" name="id23">Rationale</a></li>
70     <li><a class="reference" href="#implementation" id="id24" name="id24">Implementation</a></li>
71     <li><a class="reference" href="#backwards-compatibility" id="id25" name="id25">Backwards Compatibility</a></li>
72     <li><a class="reference" href="#id1" id="id26" name="id26">References</a></li>
73     <li><a class="reference" href="#copyright" id="id27" name="id27">Copyright</a></li>
74 g2boojum 1.1 </ul>
75     </div>
76 g2boojum 1.2 <div class="section" id="status">
77     <h1><a class="toc-backref" href="#id14" name="status">Status</a></h1>
78 g2boojum 1.3 <p>After withdrawing this GLEP temporarily, a rewritten version has
79     now been resubmitted. This version no longer tries to prevent a
80     keyword explosion, but merely tries to make it manageable.</p>
81 g2boojum 1.2 </div>
82 g2boojum 1.1 <div class="section" id="credits">
83 g2boojum 1.2 <h1><a class="toc-backref" href="#id15" name="credits">Credits</a></h1>
84 g2boojum 1.3 <p>This GLEP originated from the concerns that Daniel Robbins had with the
85     <em>x86obsd</em> keyword, and his desire to make the KEYWORDS variable more
86     &quot;feature-rich&quot;. Drobbins' original idea was that we should allow compound
87 g2boojum 1.1 keywords such as gnu/x86, gnu/ppc, and macos/ppc (which would be explicit
88     versions of the more familiar x86, ppc, and macos keywords). Method noted
89 g2boojum 1.3 that userland/arch failed to capture the full range of possibilities (what
90     about a GNU userland on a BSD kernel+libc?), and the issue has languished due
91     to a lack of reasonable solutions. The original version of this GLEP
92     generated quite useful comments which hopefully have been addressed here to
93     make the GLEP much more reasonable.</p>
94 g2boojum 1.1 </div>
95     <div class="section" id="abstract">
96 g2boojum 1.2 <h1><a class="toc-backref" href="#id16" name="abstract">Abstract</a></h1>
97 g2boojum 1.3 <p>As Gentoo branches out to support non-Linux and non-GNU systems (such as Hurd,
98     the *BSDs, or even the soon-to-be-open-sourced Solaris), the potential for an
99     &quot;explosion&quot; of possible keywords becomes rather large, since each new
100     userland/kernel/arch/whatever combination will require a new keyword. This
101     GLEP proposes a simple extension to the current KEYWORDS variable that
102     encompasses the four parameters ARCH, USERLAND, KERNEL, and LIBC, but uses
103     sensible defaults to keep the new system manageable.</p>
104 g2boojum 1.1 </div>
105     <div class="section" id="motivation">
106 g2boojum 1.2 <h1><a class="toc-backref" href="#id17" name="motivation">Motivation</a></h1>
107 g2boojum 1.1 <p>Since the beginning, Gentoo Linux has been conceived as a &quot;metadistribution&quot;
108     that combines remarkable flexibility with sensible defaults and exceptional
109     maintainablilty. The goal of the <a class="reference" href="http://www.gentoo.org/proj/en/gentoo-alt/index.xml">Gentoo-Alt</a> <a class="footnote-reference" href="#id2" id="id3" name="id3">[1]</a> project has been to extend that
110     flexibility to include systems other than GNU/Linux. For example, the author
111 g2boojum 1.3 of this GLEP has been working to create a <a class="reference" href="http://www.gentoo.org/proj/en/gentoo-alt/bsd/index.xml">version</a> <a class="footnote-reference" href="#id8" id="id9" name="id9">[3]</a> of Gentoo that uses
112     <a class="reference" href="http://www.openbsd.com">OpenBSD</a> <a class="footnote-reference" href="#id5" id="id6" name="id6">[2]</a> as the underlying kernel, userland, and libc. <a class="reference" href="http://www.openbsd.com">OpenBSD</a> <a class="footnote-reference" href="#id5" id="id7" name="id7">[2]</a> supports a
113     variety of different architectures, so, in principle, we would need a new
114     <em>openbsd-arch</em> keyword for each supported architecture. In fact, the
115     situation is even more complicated, because the <a class="reference" href="http://www.gentoo.org/proj/en/gentoo-alt/index.xml">Gentoo-Alt</a> <a class="footnote-reference" href="#id2" id="id4" name="id4">[1]</a> project would
116     eventually like to support the option of &quot;mixing-and-matching&quot;
117     GNU/*BSD/whatever userlands and libcs irrespective of the underlying kernel.
118     (<a class="reference" href="http://www.debian.org">Debian</a> <a class="footnote-reference" href="#id10" id="id11" name="id11">[4]</a>, for example has a similar BSD <a class="reference" href="http://www.debian.org/ports/netbsd/">project</a> <a class="footnote-reference" href="#id12" id="id13" name="id13">[5]</a>, except that they have
119     replaced the BSD userland with a GNU userland.) The net result is that we
120     need keywords that can specify all possible permutations of arch,
121     userland, kernel and libc. A systematic nomenclature is needed.
122     Fortunately, the author is a Chemist. <em>Grin</em></p>
123 g2boojum 1.1 </div>
124     <div class="section" id="specification">
125 g2boojum 1.2 <h1><a class="toc-backref" href="#id18" name="specification">Specification</a></h1>
126 g2boojum 1.3 <div class="section" id="keyword-fragments">
127     <h2><a class="toc-backref" href="#id19" name="keyword-fragments">Keyword Fragments</a></h2>
128     <p>Each keyword needs to specify, either explicitly or
129     implicitly, the following parameters: ARCH, USERLAND, LIBC, and KERNEL.</p>
130 g2boojum 1.1 <blockquote>
131     <dl>
132     <dt>ARCH: </dt>
133     <dd>x86, amd64, cobalt, mips64, arm, hppa, ia64, ppc64, sparc</dd>
134     <dt>USERLAND: </dt>
135     <dd>gnu, bsd</dd>
136     <dt>LIBC: </dt>
137     <dd>glibc, openbsd, freebsd, netbsd, macosx</dd>
138     <dt>KERNEL: </dt>
139     <dd>linux, selinux, openbsd, freebsd, netbsd, macosx</dd>
140     </dl>
141     </blockquote>
142     <p>(The above examples are not meant to be complete. Hurd, for example
143 g2boojum 1.3 is not included because I know very little about Hurd.)</p>
144     <p>A fully-specified keyword would look like
145     &quot;ARCH-KERNEL-USERLAND-LIBC&quot;, so, for example,
146     &quot;ppc-fbsd-gnu-glibc&quot; would indicate a Gentoo system corresponding to
147     a ppc architecture running the FreeBSD kernel with a GNU userland and glibc
148     as the system C library.</p>
149 g2boojum 1.1 </div>
150     <div class="section" id="reasonable-defaults">
151 g2boojum 1.2 <h2><a class="toc-backref" href="#id20" name="reasonable-defaults">Reasonable Defaults</a></h2>
152 g2boojum 1.3 <p>To keep this system manageable (and both to reduce typing and maintain
153     backwards compatibility), we need sensible defaults. For backwards
154     compatibility, the Gentoo default is a Linux kernel with a GNU userland
155     and glibc C library. Thus, the current crop of ARCH-based keywords
156     (x86, ppc, etcetera) require no change whatsoever. For the *BSD-based
157     systems the default USERLAND and LIBC would be those normally associated
158     with the corresponding KERNEL, so &quot;x86-obsd&quot; describes an x86 system
159     with an OpenBSD kernel, a BSD userland, and the OpenBSD C library. If
160     either USERLAND or LIBC is specified, and thus not the default, then the
161     entire four-parameter string must be used.</p>
162     </div>
163     <div class="section" id="ebuild-keyword-database">
164     <h2><a class="toc-backref" href="#id21" name="ebuild-keyword-database">Ebuild Keyword Database?</a></h2>
165     <p>One issue that has been raised is that adding a large number of keywords
166     to ebuilds is likely to become cumbersome over the long run. (One could
167     imagine that for a simple <cite>econf &amp;&amp; emake &amp;&amp; einstall</cite> ebuild that the
168     list of keywords could grow to be the lengthiest part of the ebuild.)
169     Instead, perhaps it would make more sense to move each ebuild's keywords
170     out of the ebuild proper into a separate, perhaps online, database.
171     Nothing in this GLEP would be incompatible with such an approach, so
172     any further discussion will be deferred to a possible future GLEP on
173     that topic.</p>
174 g2boojum 1.1 </div>
175     <div class="section" id="profiles">
176 g2boojum 1.3 <h2><a class="toc-backref" href="#id22" name="profiles">Profiles</a></h2>
177     <p>Along with an explosion of keywords comes a concomitant explosion of potential
178     profiles. Just as in the current system, the profile name would be
179     &quot;FLAVOR-KEYWORD-VERSION&quot; (such as &quot;default-s390-2004.1&quot;). One drawback
180     to having a large number of profiles is that maintainance becomes a
181     significant problem. In fact, one could reasonably argue that the current
182     number of profiles is already too many to be easily maintained. One proposal
183     that has been raised to simplify matters is the idea of stackable, or
184     cascading, profiles, so that only differences between profiles would have to
185     be maintained.</p>
186 g2boojum 1.1 </div>
187     </div>
188     <div class="section" id="rationale">
189 g2boojum 1.3 <h1><a class="toc-backref" href="#id23" name="rationale">Rationale</a></h1>
190 g2boojum 1.1 <p>The proposed new &quot;keywording&quot; system is far from elegant, which is
191     a substantial drawback. On the other hand, it is simple, it requires
192 g2boojum 1.3 relatively minor changes, and the changes can be implemented
193 g2boojum 1.1 gradually over time.</p>
194     </div>
195     <div class="section" id="implementation">
196 g2boojum 1.3 <h1><a class="toc-backref" href="#id24" name="implementation">Implementation</a></h1>
197     <p>Since the new keyword system is backwards-compatible with the current
198     system, &quot;implementation&quot; just means adding new keywords to ebuilds
199     as new systems are supported.</p>
200 g2boojum 1.1 </div>
201     <div class="section" id="backwards-compatibility">
202 g2boojum 1.3 <h1><a class="toc-backref" href="#id25" name="backwards-compatibility">Backwards Compatibility</a></h1>
203 g2boojum 1.1 <p>Backwards compatibility has already been addressed in some detail,
204     with the stated goal being a system that would leave all current
205 g2boojum 1.3 ebuilds working exactly as they are now.</p>
206 g2boojum 1.1 </div>
207     <div class="section" id="id1">
208 g2boojum 1.3 <h1><a class="toc-backref" href="#id26" name="id1">References</a></h1>
209 g2boojum 1.1 <table class="footnote" frame="void" id="id2" rules="none">
210     <colgroup><col class="label" /><col /></colgroup>
211     <tbody valign="top">
212     <tr><td class="label"><a name="id2">[1]</a></td><td><em>(<a class="fn-backref" href="#id3">1</a>, <a class="fn-backref" href="#id4">2</a>)</em> <a class="reference" href="http://www.gentoo.org/proj/en/gentoo-alt/index.xml">http://www.gentoo.org/proj/en/gentoo-alt/index.xml</a></td></tr>
213     </tbody>
214     </table>
215     <table class="footnote" frame="void" id="id5" rules="none">
216     <colgroup><col class="label" /><col /></colgroup>
217     <tbody valign="top">
218     <tr><td class="label"><a name="id5">[2]</a></td><td><em>(<a class="fn-backref" href="#id6">1</a>, <a class="fn-backref" href="#id7">2</a>)</em> <a class="reference" href="http://www.openbsd.com">http://www.openbsd.com</a></td></tr>
219     </tbody>
220     </table>
221     <table class="footnote" frame="void" id="id8" rules="none">
222     <colgroup><col class="label" /><col /></colgroup>
223     <tbody valign="top">
224     <tr><td class="label"><a class="fn-backref" href="#id9" name="id8">[3]</a></td><td><a class="reference" href="http://www.gentoo.org/proj/en/gentoo-alt/bsd/index.xml">http://www.gentoo.org/proj/en/gentoo-alt/bsd/index.xml</a></td></tr>
225     </tbody>
226     </table>
227     <table class="footnote" frame="void" id="id10" rules="none">
228     <colgroup><col class="label" /><col /></colgroup>
229     <tbody valign="top">
230     <tr><td class="label"><a class="fn-backref" href="#id11" name="id10">[4]</a></td><td><a class="reference" href="http://www.debian.org">http://www.debian.org</a></td></tr>
231     </tbody>
232     </table>
233     <table class="footnote" frame="void" id="id12" rules="none">
234     <colgroup><col class="label" /><col /></colgroup>
235     <tbody valign="top">
236     <tr><td class="label"><a class="fn-backref" href="#id13" name="id12">[5]</a></td><td><a class="reference" href="http://www.debian.org/ports/netbsd/">http://www.debian.org/ports/netbsd/</a></td></tr>
237     </tbody>
238     </table>
239     </div>
240     <div class="section" id="copyright">
241 g2boojum 1.3 <h1><a class="toc-backref" href="#id27" name="copyright">Copyright</a></h1>
242     <p>This document has been placed in the public domain.</p>
243 g2boojum 1.1 </div>
244     </div>
245    
246     <hr class="footer"/>
247     <div class="footer">
248     <a class="reference" href="glep-0022.txt">View document source</a>.
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