RUMS-5318 Fix race condition in lastFatalAnrSent #3071
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Use lazy initialization to prevent concurrent duplicate reads ## Problem Multiple threads could concurrently read `lastFatalAnrSent` as null before any writes occurred, causing duplicate ANR reports to be sent. The property was implemented as a getter that read from disk on every access, allowing race conditions where multiple threads would all see null and attempt to report the same ANR. ## Solution Changed `lastFatalAnrSent` from a property getter to a lazy-initialized property. This ensures the file is read exactly once in a thread-safe manner, and the value is cached in memory for all subsequent accesses.
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## develop #3071 +/- ##
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+ Coverage 71.16% 71.24% +0.08%
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Files 878 878
Lines 32129 32130 +1
Branches 5432 5432
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+ Hits 22862 22889 +27
+ Misses 7714 7707 -7
+ Partials 1553 1534 -19
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| internal val lastFatalAnrSent: Long? by lazy { | ||
| val file = File(storageDir, LAST_FATAL_ANR_SENT_FILE_NAME) | ||
| if (file.existsSafe(internalLogger)) { | ||
| file.readTextSafe(Charsets.UTF_8, internalLogger)?.toLongOrNull() | ||
| } else { |
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The new lazy cache for lastFatalAnrSent (CoreFeature) is only computed once and never updated when writeLastFatalAnrSent/deleteLastFatalAnrSent mutate the backing file. If handleAnrCrash is invoked again in the same process after the first write (e.g., iterating over multiple ApplicationExitInfo entries), the duplicate check will still read the stale cached value (often null) and can emit the same ANR repeatedly. The previous getter reread the file on every access, so the in-memory value always reflected the latest write.
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What does this PR do?
Use lazy initialization to prevent concurrent duplicate reads
Multiple threads could concurrently read
lastFatalAnrSentas null beforeany writes occurred, causing duplicate ANR reports to be sent. The property
was implemented as a getter that read from disk on every access, allowing
race conditions where multiple threads would all see null and attempt to
report the same ANR.
Changed
lastFatalAnrSentfrom a property getter to a lazy-initializedproperty. This ensures the file is read exactly once in a thread-safe manner,
and the value is cached in memory for all subsequent accesses.