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<p class="MsoNormal"><span lang="EN-GB">Dear Jack2 Maintainers,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I have a question about JackAudioDriver.cpp. It seems to me like there could be a possible race condition in JackAudioDriver::ProcessGraphSyncMaster(), where the driver would do read and write on a slave device without
waiting for graph execution end.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Below is the proposed “fix”, or what I would expect is correct, am I reading something wrong in the code? What do you guys think?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">diff --git a/common/JackAudioDriver.cpp b/common/JackAudioDriver.cpp<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">index ef7c683..9172fe8 100644<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">--- a/common/JackAudioDriver.cpp<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+++ b/common/JackAudioDriver.cpp<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">@@ -327,16 +327,12 @@ void JackAudioDriver::ProcessGraphSyncMaster()<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // fBeginDateUst is set in the "low level" layer, fEndDateUst is from previous cycle<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> if (fEngine->Process(fBeginDateUst, fEndDateUst)) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">- if (ResumeRefNum() < 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">- jack_error("JackAudioDriver::ProcessGraphSyncMaster: ResumeRefNum error");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">- }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">-<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> if (ProcessReadSlaves() < 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> jack_error("JackAudioDriver::ProcessGraphSync: ProcessReadSlaves error, engine may now behave abnormally!!");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">- if (ProcessWriteSlaves() < 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">- jack_error("JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+ if (ResumeRefNum() < 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+ jack_error("JackAudioDriver::ProcessGraphSyncMaster: ResumeRefNum error");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // Waits for graph execution end<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">@@ -344,6 +340,10 @@ void JackAudioDriver::ProcessGraphSyncMaster()<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> jack_error("JackAudioDriver::ProcessGraphSync: SuspendRefNum error, engine may now behave abnormally!!");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+ if (ProcessWriteSlaves() < 0) {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+ jack_error("JackAudioDriver::ProcessGraphSync: ProcessWriteSlaves error, engine may now behave abnormally!!");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+ }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">+<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> } else { // Graph not finished: do not activate it<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> jack_error("JackAudioDriver::ProcessGraphSync: Process error");<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">-- <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">2.7.4<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial",sans-serif">Best regards</span><span lang="EN-US"><br>
</span><span lang="EN-US" style="font-family:"Arial",sans-serif"><br>
</span><b><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial",sans-serif">Adam Miartus</span></b><span lang="EN-US"><br>
</span><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial",sans-serif">Engineering Software Multimedia (ADITG/ESM)</span><span lang="EN-US"><br>
</span><span lang="EN-US" style="font-family:"Arial",sans-serif"><br>
</span><span lang="EN-US" style="font-size:10.0pt;font-family:"Arial",sans-serif">Tel.
</span><span style="font-size:10.0pt;font-family:"Arial",sans-serif">+49 5121 49 6973</span><o:p></o:p></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
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