Thread aware live-report capture

Backtrace.xcodeproj/project.pbxproj

@@ -25,6 +25,9 @@
 		2062D9C92C457B4500E4CE3C /* Crash+CoreDataProperties.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2062D9C52C457B4500E4CE3C /* Crash+CoreDataProperties.swift */; };
 		2062D9CA2C457B4500E4CE3C /* Crash+CoreDataClass.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2062D9C42C457B4500E4CE3C /* Crash+CoreDataClass.swift */; };
 		2062D9CB2C457B4500E4CE3C /* Crash+CoreDataProperties.swift in Sources */ = {isa = PBXBuildFile; fileRef = 2062D9C52C457B4500E4CE3C /* Crash+CoreDataProperties.swift */; };
+		20B01A542DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A532DEE4DC600FED98F /* BacktraceReporterThreadSpec.swift */; };
+		20B01A552DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A532DEE4DC600FED98F /* BacktraceReporterThreadSpec.swift */; };
+		20B01A562DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A532DEE4DC600FED98F /* BacktraceReporterThreadSpec.swift */; };
 		20B01A4B2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A4A2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift */; };
 		20B01A4C2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A4A2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift */; };
 		20B01A4D2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 20B01A4A2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift */; };
@@ -428,6 +431,7 @@
 		2050DBBE2C66D98500C6CCA9 /* PrivacyInfo.xcprivacy */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.xml; path = PrivacyInfo.xcprivacy; sourceTree = "<group>"; };
 		2062D9C42C457B4500E4CE3C /* Crash+CoreDataClass.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Crash+CoreDataClass.swift"; sourceTree = "<group>"; };
 		2062D9C52C457B4500E4CE3C /* Crash+CoreDataProperties.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Crash+CoreDataProperties.swift"; sourceTree = "<group>"; };
+		20B01A532DEE4DC600FED98F /* BacktraceReporterThreadSpec.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BacktraceReporterThreadSpec.swift; sourceTree = "<group>"; };
 		20B01A4A2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CustomDirectoryBacktraceClientTests.swift; sourceTree = "<group>"; };
 		20D4E5F32CB46A41000C92BF /* BacktraceResources-Info.plist */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text.plist.xml; path = "BacktraceResources-Info.plist"; sourceTree = "<group>"; };
 		20DE4B332D4830D00076B3F6 /* NSManagedObjectContext+Extensions.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "NSManagedObjectContext+Extensions.swift"; sourceTree = "<group>"; };
@@ -888,6 +892,7 @@
 		F266B85321C77D5D00D14417 /* Tests */ = {
 			isa = PBXGroup;
 			children = (
+				20B01A532DEE4DC600FED98F /* BacktraceReporterThreadSpec.swift */,
 				20B01A4A2DB87D1200FED98F /* CustomDirectoryBacktraceClientTests.swift */,
 				20DE4B372D48615C0076B3F6 /* NSManagedObjectContextExtensionTests.swift */,
 				A24A4B5428B595D8004F5052 /* AttachmentStorageTests.swift */,
@@ -2121,6 +2126,7 @@
 				A24A4B6228B595D9004F5052 /* BacktraceFileManagerTests.swift in Sources */,
 				AFCCCE252625392300B83A28 /* ReportMetadataStorageMock.swift in Sources */,
 				A24A4B7128B595D9004F5052 /* BacktraceCredentialsTests.swift in Sources */,
+				20B01A562DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */,
 				A24A4B5F28B595D9004F5052 /* BacktraceDatabaseTests.swift in Sources */,
 				A24A4B9328B59653004F5052 /* BacktraceNotificationObserverMock.swift in Sources */,
 				A24A4B6B28B595D9004F5052 /* BacktraceRateLimiterTests.swift in Sources */,
@@ -2215,6 +2221,7 @@
 				A24A4B8228B595D9004F5052 /* BacktraceBreadcrumbTests.swift in Sources */,
 				A24A4B7628B595D9004F5052 /* DispatcherTests.swift in Sources */,
 				A24A4B6728B595D9004F5052 /* BacktraceOomWatcherTests.swift in Sources */,
+				20B01A542DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */,
 				F2AB636B2244243500939BC9 /* Quick+Throws.swift in Sources */,
 				A24A4B5B28B595D9004F5052 /* BacktraceWatcherTests.swift in Sources */,
 				A24A4B7928B595D9004F5052 /* AttributesTests.swift in Sources */,
@@ -2331,6 +2338,7 @@
 				A24A4B8128B595D9004F5052 /* BacktraceBreadcrumbTests.swift in Sources */,
 				A24A4B7528B595D9004F5052 /* DispatcherTests.swift in Sources */,
 				A24A4B6628B595D9004F5052 /* BacktraceOomWatcherTests.swift in Sources */,
+				20B01A552DEE4DCA00FED98F /* BacktraceReporterThreadSpec.swift in Sources */,
 				F2AB636A2244243500939BC9 /* Quick+Throws.swift in Sources */,
 				A24A4B5A28B595D9004F5052 /* BacktraceWatcherTests.swift in Sources */,
 				A24A4B7828B595D9004F5052 /* AttributesTests.swift in Sources */,

Sources/Public/BacktraceCrashReporter.swift

@@ -51,7 +51,20 @@ extension BacktraceCrashReporter: CrashReporting {
                             attributes: Attributes,
                             attachmentPaths: [String] = []) throws -> BacktraceReport {
 
-        let reportData = try reporter.generateLiveReport(with: exception)
+        return try generateLiveReport(exception: exception,
+                                          thread: mach_thread_self(),
+                                          attributes: attributes,
+                                          attachmentPaths: attachmentPaths)
+    }
+
+    func generateLiveReport(exception: NSException? = nil,
+                            thread: mach_port_t,
+                            attributes: Attributes,
+                            attachmentPaths: [String] = []) throws -> BacktraceReport {
+
+        defer { mach_port_deallocate(mach_task_self_, thread) }
+        let reportData = try reporter.generateLiveReport(withThread: thread, exception: exception)
+
         return try BacktraceReport(report: reportData, attributes: attributes, attachmentPaths: attachmentPaths)
     }
 

Sources/Public/Internal/CrashReporting.swift

@@ -1,7 +1,8 @@
 import Foundation
 
 protocol CrashReporting {
-    func generateLiveReport(exception: NSException?, attributes: Attributes,
+    func generateLiveReport(exception: NSException?,
+                            attributes: Attributes,
                             attachmentPaths: [String]) throws -> BacktraceReport
     func pendingCrashReport() throws -> BacktraceReport
     func purgePendingCrashReport() throws

Tests/BacktraceReporterThreadSpec.swift

@@ -0,0 +1,87 @@
+import Quick
+import Nimble
+import CrashReporter
+@testable import Backtrace
+
+final class BacktraceReporterThreadSpec: QuickSpec {
+
+    override func spec() {
+
+        describe("Thread-aware live-report capture") {
+
+            var backtraceReporter: BacktraceReporter!
+            var mockPLCR: PLCrashReporterMock!
+            var urlSession: URLSessionMock!
+            var credentials: BacktraceCredentials!
+
+            beforeEach {
+                credentials = BacktraceCredentials(
+                    endpoint: URL(string: "https://example.backtrace.io")!,
+                    token: ""
+                )
+                urlSession = URLSessionMock()
+                mockPLCR   = PLCrashReporterMock()
+
+                let crashReporter = BacktraceCrashReporter(reporter: mockPLCR)
+
+                let api = BacktraceApi(
+                    credentials: credentials,
+                    session: urlSession,
+                    reportsPerMin: 30
+                )
+
+                backtraceReporter = try! BacktraceReporter(
+                    reporter: crashReporter,
+                    api: api,
+                    dbSettings: BacktraceDatabaseSettings(),
+                    credentials: credentials,
+                    urlSession: urlSession
+                )
+            }
+
+            it("passes the calling thread to PLCrashReporter") {
+                let callThread = mach_thread_self()
+                _ = try? backtraceReporter.generate()
+                expect(mockPLCR.lastThread).to(equal(callThread))
+                mach_port_deallocate(mach_task_self_, callThread)
+            }
+
+            it("does not leak Mach SEND rights (> 2 refs to cover noise from Quick/Nimble or XCTest)") {
+                let before = sendRefCount()
+                _ = try? backtraceReporter.generate()
+                let after  = sendRefCount()
+                expect(after).to(beLessThanOrEqualTo(before + 2))
+            }
+        }
+    }
+}
+
+/// Mock PLCrashReporter stubs that records the thread parameter
+private final class PLCrashReporterMock: PLCrashReporter {
+
+    private(set) var lastThread: thread_t = mach_thread_self()
+
+    override func generateLiveReport(
+        withThread thread: thread_t,
+        exception: NSException?
+    ) throws -> Data {
+        lastThread = thread
+        return Data([0xCA, 0xFE])
+    }
+
+    override func generateLiveReport(with exception: NSException?) throws -> Data {
+        return Data([0xBE, 0xEF])
+    }
+}
+
+/// Current ref-count for thread
+private func sendRefCount() -> mach_port_urefs_t {
+    var refs: mach_port_urefs_t = 0
+    mach_port_get_refs(
+        mach_task_self_,
+        mach_thread_self(),
+        MACH_PORT_RIGHT_SEND,
+        &refs
+    )
+    return refs
+}