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22<td class="textlinks" align="left"> 22<td class="textlinks" align="left">
23[<b><a href="http://www.gentoo.org/">Gentoo Linux Home</a></b>] 23[<b><a href="http://www.gentoo.org/">Gentoo Linux Home</a></b>]
24[<b><a href="http://www.gentoo.org/proj/en/glep">GLEP Index</a></b>] 24[<b><a href="http://www.gentoo.org/proj/en/glep">GLEP Index</a></b>]
25[<b><a href="./glep-0033.txt">GLEP Source</a></b>] 25[<b><a href="./glep-0033.txt">GLEP Source</a></b>]
26</td></tr></table> 26</td></tr></table>
27<div class="document">
28<table class="rfc2822 field-list" frame="void" rules="none"> 27<table class="rfc2822 docutils field-list" frame="void" rules="none">
29<col class="field-name" /> 28<col class="field-name" />
30<col class="field-body" /> 29<col class="field-body" />
31<tbody valign="top"> 30<tbody valign="top">
32<tr class="field"><th class="field-name">GLEP:</th><td class="field-body">33</td> 31<tr class="field"><th class="field-name">GLEP:</th><td class="field-body">33</td>
33</tr> 32</tr>
34<tr class="field"><th class="field-name">Title:</th><td class="field-body">Eclass Restructure/Redesign</td> 33<tr class="field"><th class="field-name">Title:</th><td class="field-body">Eclass Restructure/Redesign</td>
35</tr> 34</tr>
36<tr class="field"><th class="field-name">Version:</th><td class="field-body">1.2</td> 35<tr class="field"><th class="field-name">Version:</th><td class="field-body">1.5</td>
37</tr> 36</tr>
38<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/xml/htdocs/proj/en/glep/glep-0033.txt?cvsroot=gentoo">2005/03/06 20:33:20</a></td> 37<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/xml/htdocs/proj/en/glep/glep-0033.txt?cvsroot=gentoo">2005/09/15 21:02:11</a></td>
39</tr> 38</tr>
40<tr class="field"><th class="field-name">Author:</th><td class="field-body">Brian Harring &lt;ferringb&#32;&#97;t&#32;gentoo.org&gt;, John Mylchreest &lt;johnm&#32;&#97;t&#32;gentoo.org&gt;</td> 39<tr class="field"><th class="field-name">Author:</th><td class="field-body">Brian Harring &lt;ferringb&#32;&#97;t&#32;gentoo.org&gt;, John Mylchreest &lt;johnm&#32;&#97;t&#32;gentoo.org&gt;</td>
41</tr> 40</tr>
42<tr class="field"><th class="field-name">Status:</th><td class="field-body">Draft</td> 41<tr class="field"><th class="field-name">Status:</th><td class="field-body">Approved</td>
43</tr> 42</tr>
44<tr class="field"><th class="field-name">Type:</th><td class="field-body">Standards Track</td> 43<tr class="field"><th class="field-name">Type:</th><td class="field-body">Standards Track</td>
45</tr> 44</tr>
46<tr class="field"><th class="field-name">Content-Type:</th><td class="field-body"><a class="reference" href="glep-0012.html">text/x-rst</a></td> 45<tr class="field"><th class="field-name">Content-Type:</th><td class="field-body"><a class="reference" href="http://www.python.org/peps/glep-0012.html">text/x-rst</a></td>
47</tr> 46</tr>
48<tr class="field"><th class="field-name">Created:</th><td class="field-body">29-Jan-2005</td> 47<tr class="field"><th class="field-name">Created:</th><td class="field-body">29-Jan-2005</td>
49</tr> 48</tr>
50<tr class="field"><th class="field-name">Post-History:</th><td class="field-body">29-Jan-2005</td> 49<tr class="field"><th class="field-name">Post-History:</th><td class="field-body">29-Jan-2005 6-Mar-2005 15-Sep-2005</td>
51</tr> 50</tr>
52</tbody> 51</tbody>
53</table> 52</table>
54<hr /> 53<hr />
55<div class="contents topic" id="contents"> 54<div class="contents topic" id="contents">
56<p class="topic-title first"><a name="contents">Contents</a></p> 55<p class="topic-title first"><a name="contents">Contents</a></p>
57<ul class="simple"> 56<ul class="simple">
57<li><a class="reference" href="#status" id="id2" name="id2">Status</a></li>
58<li><a class="reference" href="#abstract" id="id2" name="id2">Abstract</a></li> 58<li><a class="reference" href="#abstract" id="id3" name="id3">Abstract</a></li>
59<li><a class="reference" href="#terminology" id="id3" name="id3">Terminology</a></li> 59<li><a class="reference" href="#terminology" id="id4" name="id4">Terminology</a></li>
60<li><a class="reference" href="#motivation-and-rationale" id="id4" name="id4">Motivation and Rationale</a></li> 60<li><a class="reference" href="#motivation-and-rationale" id="id5" name="id5">Motivation and Rationale</a></li>
61<li><a class="reference" href="#specification" id="id5" name="id5">Specification.</a><ul> 61<li><a class="reference" href="#specification" id="id6" name="id6">Specification</a><ul>
62<li><a class="reference" href="#ebuild-libraries-elibs-for-short" id="id6" name="id6">Ebuild Libraries (elibs for short)</a></li> 62<li><a class="reference" href="#ebuild-libraries-elibs-for-short" id="id7" name="id7">Ebuild Libraries (elibs for short)</a></li>
63<li><a class="reference" href="#the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements" id="id7" name="id7">The reduced role of Eclasses, and a clarification of existing Eclass requirements</a></li> 63<li><a class="reference" href="#the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements" id="id8" name="id8">The reduced role of Eclasses, and a clarification of existing Eclass requirements</a></li>
64<li><a class="reference" href="#the-end-of-backwards-compatibility" id="id8" name="id8">The end of backwards compatibility...</a></li> 64<li><a class="reference" href="#the-end-of-backwards-compatibility" id="id9" name="id9">The end of backwards compatibility...</a></li>
65<li><a class="reference" href="#tree-restructuring" id="id9" name="id9">Tree restructuring.</a></li> 65<li><a class="reference" href="#tree-restructuring" id="id10" name="id10">Tree restructuring</a></li>
66<li><a class="reference" href="#the-start-of-a-different-phase-of-backwards-compatibility" id="id10" name="id10">The start of a different phase of backwards compatibility</a></li> 66<li><a class="reference" href="#the-start-of-a-different-phase-of-backwards-compatibility" id="id11" name="id11">The start of a different phase of backwards compatibility</a></li>
67<li><a class="reference" href="#migrating-to-the-new-setup" id="id11" name="id11">Migrating to the new setup</a></li> 67<li><a class="reference" href="#migrating-to-the-new-setup" id="id12" name="id12">Migrating to the new setup</a></li>
68</ul> 68</ul>
69</li> 69</li>
70<li><a class="reference" href="#backwards-compatibility" id="id12" name="id12">Backwards Compatibility</a></li> 70<li><a class="reference" href="#backwards-compatibility" id="id13" name="id13">Backwards Compatibility</a></li>
71<li><a class="reference" href="#copyright" id="id13" name="id13">Copyright</a></li> 71<li><a class="reference" href="#copyright" id="id14" name="id14">Copyright</a></li>
72</ul> 72</ul>
73</div> 73</div>
74<div class="section" id="status">
75<h1><a class="toc-backref" href="#id2" name="status">Status</a></h1>
76<p>Approved by the Gentoo Council on 15 September 2005.</p>
77</div>
74<div class="section" id="abstract"> 78<div class="section" id="abstract">
75<h1><a class="toc-backref" href="#id2" name="abstract">Abstract</a></h1> 79<h1><a class="toc-backref" href="#id3" name="abstract">Abstract</a></h1>
76<p>For any design, the transition from theoretical to applied exposes inadequacies 80<p>For any design, the transition from theoretical to applied exposes inadequacies
77in the original design. This document is intended to document, and propose a 81in the original design. This document is intended to document, and propose a
78revision of the current eclass setup to address current eclass inadequacies.</p> 82revision of the current eclass setup to address current eclass inadequacies.</p>
79<p>This document proposes several things- the creation of ebuild libraries, 'elibs', 83<p>This document proposes several things- the creation of ebuild libraries, 'elibs',
80a narrowing of the focus of eclasses, a move of eclasses w/in the tree, the 84a narrowing of the focus of eclasses, a move of eclasses w/in the tree, the
81addition of changelogs, and a way to allow for simple eclass gpg signing. 85addition of changelogs, and a way to allow for simple eclass gpg signing.
82In general, a large scale restructuring of what eclasses are and how they're 86In general, a large scale restructuring of what eclasses are and how they're
83implemented. Essentially version two of the eclass setup.</p> 87implemented. Essentially version two of the eclass setup.</p>
84</div> 88</div>
85<div class="section" id="terminology"> 89<div class="section" id="terminology">
86<h1><a class="toc-backref" href="#id3" name="terminology">Terminology</a></h1> 90<h1><a class="toc-backref" href="#id4" name="terminology">Terminology</a></h1>
87<p>From this point on, the proposed eclass setup will be called 'new eclasses', the 91<p>From this point on, the proposed eclass setup will be called 'new eclasses', the
88existing crop (as of this writing) will be referenced as 'old eclasses'. The 92existing crop (as of this writing) will be referenced as 'old eclasses'. The
89distinction is elaborated on within this document.</p> 93distinction is elaborated on within this document.</p>
90</div> 94</div>
91<div class="section" id="motivation-and-rationale"> 95<div class="section" id="motivation-and-rationale">
92<h1><a class="toc-backref" href="#id4" name="motivation-and-rationale">Motivation and Rationale</a></h1> 96<h1><a class="toc-backref" href="#id5" name="motivation-and-rationale">Motivation and Rationale</a></h1>
93<p>Eclasses within the tree currently are a bit of a mess- they're forced to 97<p>Eclasses within the tree currently are a bit of a mess- they're forced to
94maintain backwards compatibility w/ all previous functionality. In effect, 98maintain backwards compatibility w/ all previous functionality. In effect,
95their api is constant, and can only be added to- never changing the existing 99their api is constant, and can only be added to- never changing the existing
96functionality. This obviously is quite limiting, and leads to cruft accruing in 100functionality. This obviously is quite limiting, and leads to cruft accruing in
97eclasses as a eclasses design is refined. This needs to be dealt with prior to 101eclasses as a eclasses design is refined. This needs to be dealt with prior to
98eclass code reaching a critical mass where they become unmanageable/fragile 102eclass code reaching a critical mass where they become unmanageable/fragile
99(recent pushes for eclass versioning could be interpreted as proof of this).</p> 103(recent pushes for eclass versioning could be interpreted as proof of this).</p>
100<p>Beyond that, eclasses were originally intended as a method to allow for ebuilds 104<p>Beyond that, eclasses were originally intended as a method to allow for ebuilds
101to use a pre-existing block of code, rather then having to duplicate the code in 105to use a pre-existing block of code, rather then having to duplicate the code in
102each ebuild. This is a good thing, but there are ill effects that result from 106each ebuild. This is a good thing, but there are ill effects that result from
103the current design. Eclasses inherit other eclasses to get a single function- in 107the current design. Eclasses inherit other eclasses to get a single function- in
104doing so, modifying the the exported 'template' (default src_compile, default 108doing so, modifying the the exported 'template' (default src_compile, default
105src_unpack, various vars, etc). All the eclass designer was after was reusing a 109src_unpack, various vars, etc). All the eclass designer was after was reusing a
106function, not making their eclass sensitive to changes in the template of the 110function, not making their eclass sensitive to changes in the template of the
107eclass it's inheriting. The eclass designer -should- be aware of changes in the 111eclass it's inheriting. The eclass designer -should- be aware of changes in the
108function they're using, but shouldn't have to worry about their default src_* 112function they're using, but shouldn't have to worry about their default src_*
109and pkg_* functions being overwritten, let alone the env changes.</p> 113and pkg_* functions being overwritten, let alone the env changes.</p>
110<p>Addressing up front why a collection of eclass refinements are being rolled into 114<p>Addressing up front why a collection of eclass refinements are being rolled into
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113eclass specification was this, and that the second specification is that, 117eclass specification was this, and that the second specification is that,
114rather then requiring them to be aware of what phase of eclass changes is in 118rather then requiring them to be aware of what phase of eclass changes is in
115progress.</p> 119progress.</p>
116<p>By rolling all changes into one large change, a line is intentionally drawn in 120<p>By rolling all changes into one large change, a line is intentionally drawn in
117the sand. Old eclasses allowed for this, behaved this way. New eclasses allow 121the sand. Old eclasses allowed for this, behaved this way. New eclasses allow
118for that, and behave this way. This should reduce misconceptions about what is 122for that, and behave this way. This should reduce misconceptions about what is
119allowed/possible with eclasses, thus reducing bugs that result from said 123allowed/possible with eclasses, thus reducing bugs that result from said
120misconceptions.</p> 124misconceptions.</p>
121<p>A few words on elibs- think of them as a clear definition between behavioral 125<p>A few words on elibs- think of them as a clear definition between behavioral
122functionality of an eclass, and the library functionality. Eclass's modify 126functionality of an eclass, and the library functionality. Eclass's modify
123template data, and are the basis for other ebuilds- elibs, however are <em>just</em> 127template data, and are the basis for other ebuilds- elibs, however are <em>just</em>
124common bash functionality.</p> 128common bash functionality.</p>
125<p>Consider the majority of the portage bin/* scripts- these all are candidates for 129<p>Consider the majority of the portage bin/* scripts- these all are candidates for
126being added to the tree as elibs, as is the bulk of eutils.</p> 130being added to the tree as elibs, as is the bulk of eutils.</p>
127</div> 131</div>
128<div class="section" id="specification"> 132<div class="section" id="specification">
129<h1><a class="toc-backref" href="#id5" name="specification">Specification.</a></h1> 133<h1><a class="toc-backref" href="#id6" name="specification">Specification</a></h1>
130<p>The various parts of this proposal are broken down into a set of changes and 134<p>The various parts of this proposal are broken down into a set of changes and
131elaborations on why a proposed change is preferable. It's advisable to the 135elaborations on why a proposed change is preferable. It's advisable to the
132reader that this be read serially, rather then jumping around.</p> 136reader that this be read serially, rather then jumping around.</p>
133<div class="section" id="ebuild-libraries-elibs-for-short"> 137<div class="section" id="ebuild-libraries-elibs-for-short">
134<h2><a class="toc-backref" href="#id6" name="ebuild-libraries-elibs-for-short">Ebuild Libraries (elibs for short)</a></h2> 138<h2><a class="toc-backref" href="#id7" name="ebuild-libraries-elibs-for-short">Ebuild Libraries (elibs for short)</a></h2>
135<p>As briefly touched upon in Motivation and Rationale, the original eclass design 139<p>As briefly touched upon in Motivation and Rationale, the original eclass design
136allowed for the eclass to modify the metadata of an ebuild, metadata being the 140allowed for the eclass to modify the metadata of an ebuild, metadata being the
137DEPENDS, RDEPENDS, SRC_URI, IUSE, etc, vars that are required to be constant, 141DEPENDS, RDEPENDS, SRC_URI, IUSE, etc, vars that are required to be constant,
138and used by portage for dep resolution, fetching, etc. Using the earlier 142and used by portage for dep resolution, fetching, etc. Using the earlier
139example, if you're after a single function from an eclass (say epatch from 143example, if you're after a single function from an eclass (say epatch from
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151initialization of the library that is absolutely needed. Additionally, they 155initialization of the library that is absolutely needed. Additionally, they
152cannot modify any ebuild template functions- src_compile, src_unpack. Since they are 156cannot modify any ebuild template functions- src_compile, src_unpack. Since they are
153required to not modify the metadata keys, nor in any way affect the ebuild aside 157required to not modify the metadata keys, nor in any way affect the ebuild aside
154from providing functionality, they can be conditionally pulled in. They also 158from providing functionality, they can be conditionally pulled in. They also
155are allowed to pull in other elibs, but strictly just elibs- no eclasses, just 159are allowed to pull in other elibs, but strictly just elibs- no eclasses, just
156other elibs. A real world example would be the eutils eclass.</p> 160other elibs. A real world example would be the eutils eclass.</p>
157<p>Portage, since the elib's don't modify metadata, isn't required to track elibs 161<p>Portage, since the elib's don't modify metadata, isn't required to track elibs
158as it tracks eclasses. Thus a change in an elib doesn't result in half the tree 162as it tracks eclasses. Thus a change in an elib doesn't result in half the tree
159forced to be regenerated/marked stale when changed (this is more of an infra 163forced to be regenerated/marked stale when changed (this is more of an infra
160benefit, although regen's that take too long due to eclass changes have been 164benefit, although regen's that take too long due to eclass changes have been
161known to cause rsync issues due to missing timestamps).</p> 165known to cause rsync issues due to missing timestamps).</p>
162<p>Elibs will not be available in the global scope of an eclass, or ebuild- nor during the 166<p>Elibs will not be available in the global scope of an eclass, or ebuild- nor during the
163depends phase (basically a phase that sources the ebuild, to get it's metadata). Elib 167depends phase (basically a phase that sources the ebuild, to get its metadata). Elib
164calls in the global scope will be tracked, but the elib will not be loaded till just before 168calls in the global scope will be tracked, but the elib will not be loaded till just before
165the setup phase (pkg_setup). There are two reasons for this- first, it ensures elibs are 169the setup phase (pkg_setup). There are two reasons for this- first, it ensures elibs are
166completely incapable of modifying metadata. There is no room for confusion, late loading 170completely incapable of modifying metadata. There is no room for confusion, late loading
167of elibs gives you the functionality for all phases, except for depends- depends being the 171of elibs gives you the functionality for all phases, except for depends- depends being the
168only phase that is capable of specifying metadata. Second, as an added bonus, late 172only phase that is capable of specifying metadata. Second, as an added bonus, late
169loading reduces the amount of bash sourced for a regen- faster regens. This however is minor, 173loading reduces the amount of bash sourced for a regen- faster regens. This however is minor,
170and is an ancillary benefit of the first reason.</p> 174and is an ancillary benefit of the first reason.</p>
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184 func x() { echo &quot;this is invalid, do not do it.&quot;; } 188 func x() { echo &quot;this is invalid, do not do it.&quot;; }
185fi 189fi
186</pre> 190</pre>
187<p>Regarding maintainability of elibs, it should be a less of a load then old 191<p>Regarding maintainability of elibs, it should be a less of a load then old
188eclasses. One of the major issues with old eclasses is that their functions are 192eclasses. One of the major issues with old eclasses is that their functions are
189quite incestuous- they're bound tightly to the env they're defined in. This 193quite incestuous- they're bound tightly to the env they're defined in. This
190makes eclass functions a bit fragile- the restrictions on what can, and cannot 194makes eclass functions a bit fragile- the restrictions on what can, and cannot
191be done in elibs will address this, making functionality less fragile (thus a 195be done in elibs will address this, making functionality less fragile (thus a
192bit more maintainable).</p> 196bit more maintainable).</p>
193<p>There is no need for backwards compatibility with elibs- they just must work 197<p>There is no need for backwards compatibility with elibs- they just must work
194against the current tree. Thus elibs can be removed when the tree no longer 198against the current tree. Thus elibs can be removed when the tree no longer
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199what elibs are, what they are capable of, and how to use them is nailed down as much as 203what elibs are, what they are capable of, and how to use them is nailed down as much as
200possible to avoid <em>any</em> ambiguity related to them. The intention is to make it clear, 204possible to avoid <em>any</em> ambiguity related to them. The intention is to make it clear,
201such that no misconceptions occur, resulting in bugs.</p> 205such that no misconceptions occur, resulting in bugs.</p>
202</div> 206</div>
203<div class="section" id="the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements"> 207<div class="section" id="the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements">
204<h2><a class="toc-backref" href="#id7" name="the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements">The reduced role of Eclasses, and a clarification of existing Eclass requirements</a></h2> 208<h2><a class="toc-backref" href="#id8" name="the-reduced-role-of-eclasses-and-a-clarification-of-existing-eclass-requirements">The reduced role of Eclasses, and a clarification of existing Eclass requirements</a></h2>
205<p>Since elibs are now intended on holding common bash functionality, the focus of 209<p>Since elibs are now intended on holding common bash functionality, the focus of
206eclasses should be in defining an appropriate template for ebuilds. For example, 210eclasses should be in defining an appropriate template for ebuilds. For example,
207defining common DEPENDS, RDEPENDS, src_compile functions, src_unpack, etc. 211defining common DEPENDS, RDEPENDS, src_compile functions, src_unpack, etc.
208Additionally, eclasses should pull in any elibs they need for functionality.</p> 212Additionally, eclasses should pull in any elibs they need for functionality.</p>
209<p>Eclass functionality that isn't directly related to the metadata, or src_* and 213<p>Eclass functionality that isn't directly related to the metadata, or src_* and
210pkg_* funcs should be shifted into elibs to allow for maximal code reuse. This 214pkg_* funcs should be shifted into elibs to allow for maximal code reuse. This
211however isn't a hard requirement, merely a strongly worded suggestion.</p> 215however isn't a hard requirement, merely a strongly worded suggestion.</p>
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238just that. As such new eclasses (the true distinction of new vs old is 242just that. As such new eclasses (the true distinction of new vs old is
239elaborated in the next section) can be removed from the tree once they're no 243elaborated in the next section) can be removed from the tree once they're no
240longer in use.</p> 244longer in use.</p>
241</div> 245</div>
242<div class="section" id="the-end-of-backwards-compatibility"> 246<div class="section" id="the-end-of-backwards-compatibility">
243<h2><a class="toc-backref" href="#id8" name="the-end-of-backwards-compatibility">The end of backwards compatibility...</a></h2> 247<h2><a class="toc-backref" href="#id9" name="the-end-of-backwards-compatibility">The end of backwards compatibility...</a></h2>
244<p>With current eclasses, once the eclass is in use, it's api can no longer be 248<p>With current eclasses, once the eclass is in use, its api can no longer be
245changed, nor can the eclass ever be removed from the tree. This is why we still 249changed, nor can the eclass ever be removed from the tree. This is why we still
246have <em>ancient</em> eclasses that are completely unused sitting in the tree, for 250have <em>ancient</em> eclasses that are completely unused sitting in the tree, for
247example inherit.eclass . The reason for this, not surprisingly is a portage 251example inherit.eclass. The reason for this, not surprisingly, is a portage
248deficiency- on unmerging an installed ebuild, portage used the eclass from the 252deficiency: on unmerging an installed ebuild, portage used the eclass from the
249current tree.</p> 253current tree.</p>
250<p>For a real world example of this, if you merged a glibc 2 years back, whatever 254<p>For a real world example of this, if you merged a glibc 2 years back, whatever
251eclasses it used must still be compatible, or you may not be able to unmerge the 255eclasses it used must still be compatible, or you may not be able to unmerge the
252older glibc version during an upgrade to a newer version. So either the glibc 256older glibc version during an upgrade to a newer version. So either the glibc
253maintainer is left with the option of leaving people using ancient versions out 257maintainer is left with the option of leaving people using ancient versions out
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281still be able to access them.</p> 285still be able to access them.</p>
282<p>In other words, these new eclasses would in effect, be old eclasses since older 286<p>In other words, these new eclasses would in effect, be old eclasses since older
283portage versions could still access them.</p> 287portage versions could still access them.</p>
284</div> 288</div>
285<div class="section" id="tree-restructuring"> 289<div class="section" id="tree-restructuring">
286<h2><a class="toc-backref" href="#id9" name="tree-restructuring">Tree restructuring.</a></h2> 290<h2><a class="toc-backref" href="#id10" name="tree-restructuring">Tree restructuring</a></h2>
287<p>There are only two way to block the existing (as of this writing) inherit 291<p>There are only two way to block the existing (as of this writing) inherit
288functionality from accessing the new eclasses- either change the extension of 292functionality from accessing the new eclasses- either change the extension of
289eclasses to something other then 'eclass', or to have them stored in a separate 293eclasses to something other then 'eclass', or to have them stored in a separate
290subdirectory of the tree then eclass.</p> 294subdirectory of the tree then eclass.</p>
291<p>The latter is preferable, and the proposed solution. Reasons are- the current 295<p>The latter is preferable, and the proposed solution. Reasons are- the current
… …
297<p>If it's unclear as to why the old inherit function <em>cannot</em> access the new 301<p>If it's unclear as to why the old inherit function <em>cannot</em> access the new
298eclasses, please reread the previous section. It's unfortunately a requirement 302eclasses, please reread the previous section. It's unfortunately a requirement
299to take advantage of all that the next major portage release will allow.</p> 303to take advantage of all that the next major portage release will allow.</p>
300<p>The proposed directory structure is ${PORTDIR}/include/{eclass,elib}. 304<p>The proposed directory structure is ${PORTDIR}/include/{eclass,elib}.
301Something like ${PORTDIR}/new-eclass, or ${PORTDIR}/eclass-ng could be used 305Something like ${PORTDIR}/new-eclass, or ${PORTDIR}/eclass-ng could be used
302(although many would cringe at the -ng), but such a name is unwise. Consider the 306(although many would cringe at the -ng), but such a name is unwise. Consider the
303possibility (likely a fact) that new eclasses someday may be found lacking, and 307possibility (likely a fact) that new eclasses someday may be found lacking, and
304refined further (version three as it were). Or perhaps we want to add yet more 308refined further (version three as it were). Or perhaps we want to add yet more
305functionality with direct relation to sourcing new files, and we would then need 309functionality with direct relation to sourcing new files, and we would then need
306to further populate ${PORTDIR}.</p> 310to further populate ${PORTDIR}.</p>
307<p>The new-eclass directory will be (at least) 2 levels deep- for example:</p> 311<p>The new-eclass directory will be (at least) 2 levels deep- for example:</p>
308<dl> 312<dl class="docutils">
309<dt>::</dt> 313<dt>::</dt>
310<dd>kernel/ 314<dd>kernel/
311kernel/linux-info.eclass 315kernel/linux-info.eclass
312kernel/linux-mod.eclass 316kernel/linux-mod.eclass
313kernel/kernel-2.6.eclass 317kernel/kernel-2.6.eclass
… …
322saner/easier signing of eclasses- you can just stick a signed 326saner/easier signing of eclasses- you can just stick a signed
323Manifest file w/in that grouping, thus providing the information portage needs 327Manifest file w/in that grouping, thus providing the information portage needs
324to ensure no files are missing, and that nothing has been tainted.</p> 328to ensure no files are missing, and that nothing has been tainted.</p>
325<p>The elib directory will be structured in the same way, for the same reasons.</p> 329<p>The elib directory will be structured in the same way, for the same reasons.</p>
326<p>Repoman will have to be extended to work within new eclass and elib groups, and 330<p>Repoman will have to be extended to work within new eclass and elib groups, and
327to handle signing and committing. This is intentional, and a good thing. This 331to handle signing and committing. This is intentional, and a good thing. This
328gives repoman the possibility of doing sanity checks on elibs/new eclasses.</p> 332gives repoman the possibility of doing sanity checks on elibs/new eclasses.</p>
329<p>Note these checks will not prevent developers from doing dumb things with eclass- 333<p>Note these checks will not prevent developers from doing dumb things with eclass-
330these checks would only be capable of doing basic sanity checks, such as syntax checks. 334these checks would only be capable of doing basic sanity checks, such as syntax checks.
331There is no way to prevent people from doing dumb things (exempting perhaps repeated 335There is no way to prevent people from doing dumb things (exempting perhaps repeated
332applications of a cattle prod)- these are strictly automatic checks, akin to repoman's 336applications of a cattle prod)- these are strictly automatic checks, akin to repoman's
333dependency checks.</p> 337dependency checks.</p>
334</div> 338</div>
335<div class="section" id="the-start-of-a-different-phase-of-backwards-compatibility"> 339<div class="section" id="the-start-of-a-different-phase-of-backwards-compatibility">
336<h2><a class="toc-backref" href="#id10" name="the-start-of-a-different-phase-of-backwards-compatibility">The start of a different phase of backwards compatibility</a></h2> 340<h2><a class="toc-backref" href="#id11" name="the-start-of-a-different-phase-of-backwards-compatibility">The start of a different phase of backwards compatibility</a></h2>
337<p>As clarified above, new eclasses will exist in a separate directory that will be 341<p>As clarified above, new eclasses will exist in a separate directory that will be
338intentionally inaccessible to the inherit function. As such, users of older 342intentionally inaccessible to the inherit function. As such, users of older
339portage versions <em>will</em> have to upgrade to merge any ebuild that uses elibs/new 343portage versions <em>will</em> have to upgrade to merge any ebuild that uses elibs/new
340eclasses. A depend on the next major portage version would transparently handle 344eclasses. A depend on the next major portage version would transparently handle
341this for rsync users.</p> 345this for rsync users.</p>
342<p>There still is the issue of users who haven't upgraded to the required portage 346<p>There still is the issue of users who haven't upgraded to the required portage
343version. This is a minor concern frankly- portage releases include new 347version. This is a minor concern frankly- portage releases include new
344functionality, and bug fixes. If they won't upgrade, it's assumed they have 348functionality, and bug fixes. If they won't upgrade, it's assumed they have
345their reasons and are big boys, thus able to handle the complications themselves.</p> 349their reasons and are big boys, thus able to handle the complications themselves.</p>
346<p>The real issue is broken envs, whether in binpkgs, or for installed packages. 350<p>The real issue is broken envs, whether in binpkgs, or for installed packages.
347Two options exist- either the old eclasses are left in the tree indefinitely, or 351Two options exist- either the old eclasses are left in the tree indefinitely, or
348they're left for N months, then shifted out of the tree, and into a tarball that 352they're left for N months, then shifted out of the tree, and into a tarball that
… …
377the old eclass compat ebuild.</p> 381the old eclass compat ebuild.</p>
378<p>Note for this to happen requires either rather... unwise uses of root, or significant 382<p>Note for this to happen requires either rather... unwise uses of root, or significant
379fs corruption. Regardless of the cause, it's quite likely for this to even become an 383fs corruption. Regardless of the cause, it's quite likely for this to even become an
380issue, the system's vdb is completely unusable. It's a moot issue at that point. 384issue, the system's vdb is completely unusable. It's a moot issue at that point.
381If you lose your vdb, or it gets seriously damaged, it's akin to lobotomizing portage- 385If you lose your vdb, or it gets seriously damaged, it's akin to lobotomizing portage-
382it doesn't know what's installed, it doesn't know of it's own files, and in general, 386it doesn't know what's installed, it doesn't know of its own files, and in general,
383a rebuilding of the system is about the only sane course of action. The missing env is 387a rebuilding of the system is about the only sane course of action. The missing env is
384truly the least of the users concern in such a case.</p> 388truly the least of the users concern in such a case.</p>
385<p>Continuing with the more likely scenario, users unwilling to upgrade portage will 389<p>Continuing with the more likely scenario, users unwilling to upgrade portage will
386<em>not</em> be left out in the rain. Merging the old eclass compat ebuild will provide 390<em>not</em> be left out in the rain. Merging the old eclass compat ebuild will provide
387the missing eclasses, thus providing that lost functionality .</p> 391the missing eclasses, thus providing that lost functionality.</p>
388<p>Note the intention isn't to force them to upgrade, hence the ability to restore the 392<p>Note the intention isn't to force them to upgrade, hence the ability to restore the
389lost functionality. The intention is to clean up the existing mess, and allow us 393lost functionality. The intention is to clean up the existing mess, and allow us
390to move forward. The saying &quot;you've got to break a few eggs to make an omelet&quot; 394to move forward. The saying &quot;you've got to break a few eggs to make an omelet&quot;
391is akin, exempting the fact we're providing a way to make the eggs whole again 395is akin, exempting the fact we're providing a way to make the eggs whole again
392(the king's men would've loved such an option).</p> 396(the king's men would've loved such an option).</p>
393</div> 397</div>
394<div class="section" id="migrating-to-the-new-setup"> 398<div class="section" id="migrating-to-the-new-setup">
395<h2><a class="toc-backref" href="#id11" name="migrating-to-the-new-setup">Migrating to the new setup</a></h2> 399<h2><a class="toc-backref" href="#id12" name="migrating-to-the-new-setup">Migrating to the new setup</a></h2>
396<p>As has been done in the past whenever a change in the tree results in ebuilds 400<p>As has been done in the past whenever a change in the tree results in ebuilds
397requiring a specific version of portage, as ebuilds migrate to the new eclasses, 401requiring a specific version of portage, as ebuilds migrate to the new eclasses,
398they should depend on a version of portage that supports it. From the users 402they should depend on a version of portage that supports it. From the users
399viewpoint, this transparently handles the migration.</p> 403viewpoint, this transparently handles the migration.</p>
400<p>This isn't so transparent for devs or a particular infrastructure server however. 404<p>This isn't so transparent for devs or a particular infrastructure server however.
… …
406<p>Additionally, prior to any ebuilds in the tree using the new eclasses, the 410<p>Additionally, prior to any ebuilds in the tree using the new eclasses, the
407infrastructure server that generates the cache for rsync users will have to 411infrastructure server that generates the cache for rsync users will have to
408either be upgraded to a version of portage supporting new eclasses, or patched. 412either be upgraded to a version of portage supporting new eclasses, or patched.
409The former being much more preferable then the latter for the portage devs.</p> 413The former being much more preferable then the latter for the portage devs.</p>
410<p>Beyond that, an appropriate window for old eclasses to exist in the tree must be 414<p>Beyond that, an appropriate window for old eclasses to exist in the tree must be
411determined, and prior to that window passing an ebuild must be added to the tree 415determined, and prior to that window passing, an ebuild must be added to the tree
412so users can get the old eclasses if needed.</p> 416so users can get the old eclasses if needed.</p>
413<p>For eclass devs to migrate from old to new, it is possible for them to just 417<p>For eclass devs to migrate from old to new, it is possible for them to just
414transfer the old eclass into an appropriate grouping in the new eclass directory, 418transfer the old eclass into an appropriate grouping in the new eclass directory,
415although it's advisable they cleanse all cruft out of the eclass. You can 419although it's advisable they cleanse all cruft out of the eclass. You can
416migrate ebuilds gradually over to the new eclass, and don't have to worry about 420migrate ebuilds gradually over to the new eclass, and don't have to worry about
417having to support ebuilds from X years back.</p> 421having to support ebuilds from X years back.</p>
418<p>Essentially, you have a chance to nail the design perfectly/cleanly, and have a 422<p>Essentially, you have a chance to nail the design perfectly/cleanly, and have a
419window in which to redesign it. It's humbly suggested eclass devs take 423window in which to redesign it. It's humbly suggested eclass devs take
420advantage of it. :)</p> 424advantage of it. :)</p>
421</div> 425</div>
422</div> 426</div>
423<div class="section" id="backwards-compatibility"> 427<div class="section" id="backwards-compatibility">
424<h1><a class="toc-backref" href="#id12" name="backwards-compatibility">Backwards Compatibility</a></h1> 428<h1><a class="toc-backref" href="#id13" name="backwards-compatibility">Backwards Compatibility</a></h1>
425<p>All backwards compatibility issues are addressed in line, but a recap is offered- 429<p>All backwards compatibility issues are addressed in line, but a recap is offered-
426it's suggested that if the a particular compatibility issue is 430it's suggested that if the a particular compatibility issue is
427questioned/worried over, the reader read the relevant section. There should be 431questioned/worried over, the reader read the relevant section. There should be
428a more in depth discussion of the issue, along with a more extensive explanation 432a more in depth discussion of the issue, along with a more extensive explanation
429of the potential solutions, and reasons for the chosen solution.</p> 433of the potential solutions, and reasons for the chosen solution.</p>
430<p>To recap:</p> 434<p>To recap:</p>
431<pre class="literal-block"> 435<pre class="literal-block">
432New eclasses and elib functionality will be tied to a specific portage 436New eclasses and elib functionality will be tied to a specific portage
433version. A DEPENDs on said portage version should address this for rsync 437version. A DEPENDs on said portage version should address this for rsync
434users who refuse to upgrade to a portage version that supports the new 438users who refuse to upgrade to a portage version that supports the new
435eclasses/elibs and will gradually be unable to merge ebuilds that use said 439eclasses/elibs and will gradually be unable to merge ebuilds that use said
436functionality. It is their choice to upgrade, as such, the gradual 440functionality. It is their choice to upgrade, as such, the gradual
437'thinning' of available ebuilds should they block the portage upgrade is 441'thinning' of available ebuilds should they block the portage upgrade is
438their responsibility. 442their responsibility.
439 443
440Old eclasses at some point in the future should be removed from the tree, 444Old eclasses at some point in the future should be removed from the tree,
441and released in a tarball/ebuild. This will cause installed ebuilds that 445and released in a tarball/ebuild. This will cause installed ebuilds that
442rely on the old eclass to be unable to unmerge, with the same applying for 446rely on the old eclass to be unable to unmerge, with the same applying for
443merging of binpkgs dependent on the following paragraph. 447merging of binpkgs dependent on the following paragraph.
444 448
445The old eclass-compat is only required for users who do not upgrade their 449The old eclass-compat is only required for users who do not upgrade their
446portage installation, and one further exemption- if the user has somehow 450portage installation, and one further exemption- if the user has somehow
… …
451strictly to be complete, it's not much of a real world scenario as elaborated 455strictly to be complete, it's not much of a real world scenario as elaborated
452above. 456above.
453</pre> 457</pre>
454</div> 458</div>
455<div class="section" id="copyright"> 459<div class="section" id="copyright">
456<h1><a class="toc-backref" href="#id13" name="copyright">Copyright</a></h1> 460<h1><a class="toc-backref" href="#id14" name="copyright">Copyright</a></h1>
457<p>This document has been placed in the public domain.</p> 461<p>This document has been placed in the public domain.</p>
458</div> 462</div>
459</div>
460 463
464</div>
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