fix(ios): CVPixelBuffer race condition crash in captureOutput#1678
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harSofja wants to merge 1 commit intojuliansteenbakker:developfrom
Open
fix(ios): CVPixelBuffer race condition crash in captureOutput#1678harSofja wants to merge 1 commit intojuliansteenbakker:developfrom
harSofja wants to merge 1 commit intojuliansteenbakker:developfrom
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Capture a strong reference to latestBuffer before dispatching to the background thread. Previously, self.latestBuffer was read on the background queue, but could be overwritten or nilled on the main thread by the next camera frame or releaseCamera(), causing EXC_BAD_ACCESS in VTCreateCGImageFromCVPixelBuffer / CVPixelBufferGetWidth. Also adds changelog entry and bumps patch version to 7.2.1. Fixes juliansteenbakker#1545
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Summary
Fixes a race condition in
captureOutputwhereself.latestBufferis read on a background thread (DispatchQueue.global(qos: .userInitiated)) after being deallocated or overwritten on the main thread by the next camera frame orreleaseCamera().The fix captures a strong reference to the buffer before dispatching to the background queue, ensuring the
CVPixelBufferis retained for the duration of the background processing.Also adds a changelog entry and bumps the patch version to 7.2.1.
Crash Stack Trace (from Xcode Organizer)
Thread 1 Crashed:
0 CoreVideo CVPixelBufferGetWidth + 28
1 VideoToolbox VTCreateCGImageFromCVPixelBuffer
2 mobile_scanner closure #1 in MobileScannerPlugin.captureOutput(:didOutput:from:)
3 mobile_scanner MobileScannerPlugin.captureOutput(:didOutput:from:) (partial)
4 libdispatch _dispatch_call_block_and_release
5 libdispatch _dispatch_client_callout
Environment
Related Issue
Fixes #1545