Fix CDM_Application::myMetaDataLookUpTable/CDM_MetaData reentrancy races (#1396)#1397
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gsdali wants to merge 2 commits into
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Fix CDM_Application::myMetaDataLookUpTable/CDM_MetaData reentrancy races (#1396)#1397gsdali wants to merge 2 commits into
gsdali wants to merge 2 commits into
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CDM_Application::myMetaDataLookUpTable is shared process-wide (via the CDM_Application/CDF_Application singleton) with no synchronization on its map accesses (CDM_MetaData::LookUp, CDM_Document::SetMetaData's iteration) or on individual CDM_MetaData objects' myIsRetrieved/myDocument fields. Add a mutex on CDM_Application guarding the map, threaded through every access point, plus a private mutex on CDM_MetaData guarding its own fields.
This was referenced Jul 23, 2026
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Fixes #1396.
CDM_Application::myMetaDataLookUpTableis shared process-wide (oneCDM_Application/CDF_Applicationinstance per process, per the singleton pattern fixed in #1389/#1390) with zerosynchronization on its map accesses or on the individual
CDM_MetaDataobjects it hands out. See#1396 for the full trace and TSan evidence (1 confirmed race + SIGABRT → 0 races with this patch).
Fix
CDM_Applicationgets amutable std::mutex myMetaDataLookUpTableMutex+MetaDataLookUpTableMutex()accessor, threaded through every access point:CDM_MetaData::LookUp()'s two overloads (now take the mutex as an explicit parameter alongsidethe map, since they're
staticand operate on a caller-supplied table+mutex pair),CDF_FWOSDriver's constructor/call sites,XmlLDrivers_DocumentRetrievalDriver:: ReadFromDomDocument, andPCDM_ReferenceIterator::MetaData.CDM_Document::SetMetaData()'sfull-table iteration is now guarded for its duration.
CDM_MetaDatagets its own privatemutable std::mutex myDocumentMutexguardingmyIsRetrieved/myDocument, sinceSetDocument/UnsetDocument/IsRetrieved/Documentarecalled on one shared
CDM_MetaDatainstance from whichever thread looked it up and,independently, from another thread's document destructor.
Testing
DataExchange): 1 confirmed race + SIGABRT (exit 134) on unpatched master → 0 races, clean exit,
across repeated runs (8×25, 10×60, 3×8×40 thread/round configurations).
https://github.com/SecondMouseAU/OCCTSwift/tree/main/Scripts/repro/353-cdm-metadata-lookup-table