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This is an automatically generated e-mail. To reply, visit:
<a href="https://git.reviewboard.kde.org/r/126961/">https://git.reviewboard.kde.org/r/126961/</a>
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<p style="margin-top: 0;">On February 2nd, 2016, 12:43 p.m. UTC, <b>Sebastian Kügler</b> wrote:</p>
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<a href="https://git.reviewboard.kde.org/r/126961/diff/1/?file=442514#file442514line629" style="color: black; font-weight: bold; text-decoration: underline;">shell/shellcorona.cpp</a>
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(Diff revision 1)
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<th bgcolor="#e9eaa8" style="border-right: 1px solid #C0C0C0;" align="right"><font size="2">629</font></th>
<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> <span class="k">return</span> <span class="n">QGuiApplication</span><span class="o">::</span><span class="n">screens</span><span class="p">().</span><span class="n">count</span><span class="p">();</span></pre></td>
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<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> <span class="k">return</span> <span class="n">m_screenConfiguration</span><span class="o">-></span><span class="n">outputs</span><span class="p">().</span><span class="n">count</span><span class="p">();</span></pre></td>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">m_screenConfiguration may still be a nullptr here, since it's set only after GetConfigOperation returns.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">That may well be the reason why the sync QScreen's count is used here, but this leads to problems down the road, as you note.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">We could make sure we have the number of screens returned here by making GetConfigOperation sync, so using its exec() and thus blocking in the setShell call.</p></pre>
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<pre style="margin-left: 1em; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">ooh good catch.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">I /think/ a simple if (null) return 0; is semantically correct.
As this should be a count of screens plasma knows about.</p></pre>
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<p>- David</p>
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<p>On February 1st, 2016, 11:08 p.m. UTC, David Edmundson wrote:</p>
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<div>Review request for Plasma.</div>
<div>By David Edmundson.</div>
<p style="color: grey;"><i>Updated Feb. 1, 2016, 11:08 p.m.</i></p>
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<b style="color: #575012; font-size: 10pt;">Repository: </b>
plasma-workspace
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">We were mixing KScreen and QScreen API badly.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Corona.cpp checks we are requesting a containment for a valid screen
if (screen >= 0 && screen < numScreens()) {</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">This fails as numScreens() is Qt API based, whereas the signal we're
adding the output for is ShellCorona::addOutput so we have an effective race condition.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">BUG: 351777</p></pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Testing </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Started Plasma on dual screen.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Ideally we need to do more testing before backporting, as that entire codebase is a disgrace.</p></pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>shell/shellcorona.cpp <span style="color: grey">(762e503bf59fe648fb0f5b76a36229aa43c563e5)</span></li>
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<p><a href="https://git.reviewboard.kde.org/r/126961/diff/" style="margin-left: 3em;">View Diff</a></p>
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