feat: Experimental support for Swift Async stacktraces (#3051)

Adds support for stitching async Swift Concurrency frames using backtrace_async

Co-authored-by: Philipp Hofmann <[email protected]>

Author: brustolin

.github/workflows/test.yml

@@ -130,14 +130,6 @@ jobs:
             xcode: '14.3'
             test-destination-os: 'latest'
 
-          # MetricKit doesn't exist for tvOS, so we can still run unit tests with
-          # Xcode 12 for it.
-          # tvOS 14
-          - runs-on: macos-11
-            platform: 'tvOS'
-            xcode: '12.5.1'
-            test-destination-os: 'latest'
-
           # tvOS 15
           - runs-on: macos-12
             platform: 'tvOS'

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+### Features
+
+- Experimental support for Swift Async stacktraces (#3051)
+
 ### Fixes
 
 - Changed `Trace` serialized value of `sampled` from string to boolean (#3067)

Sentry.xcodeproj/project.pbxproj

@@ -190,7 +190,7 @@
 		63FE710120DA4C1000CDBAE8 /* SentryCrashDate.h in Headers */ = {isa = PBXBuildFile; fileRef = 63FE700720DA4C1000CDBAE8 /* SentryCrashDate.h */; };
 		63FE710320DA4C1000CDBAE8 /* SentryCrashMachineContext_Apple.h in Headers */ = {isa = PBXBuildFile; fileRef = 63FE700820DA4C1000CDBAE8 /* SentryCrashMachineContext_Apple.h */; };
 		63FE710520DA4C1000CDBAE8 /* SentryCrashLogger.c in Sources */ = {isa = PBXBuildFile; fileRef = 63FE700920DA4C1000CDBAE8 /* SentryCrashLogger.c */; };
-		63FE710720DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.c in Sources */ = {isa = PBXBuildFile; fileRef = 63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.c */; };
+		63FE710720DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.m in Sources */ = {isa = PBXBuildFile; fileRef = 63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.m */; };
 		63FE710920DA4C1000CDBAE8 /* SentryCrashFileUtils.h in Headers */ = {isa = PBXBuildFile; fileRef = 63FE700B20DA4C1000CDBAE8 /* SentryCrashFileUtils.h */; };
 		63FE710B20DA4C1000CDBAE8 /* SentryCrashMach.c in Sources */ = {isa = PBXBuildFile; fileRef = 63FE700C20DA4C1000CDBAE8 /* SentryCrashMach.c */; };
 		63FE710D20DA4C1000CDBAE8 /* SentryCrashStackCursor_MachineContext.c in Sources */ = {isa = PBXBuildFile; fileRef = 63FE700D20DA4C1000CDBAE8 /* SentryCrashStackCursor_MachineContext.c */; };
@@ -742,6 +742,8 @@
 		D8370B6C273DF20F00F66E2D /* SentryNSURLSessionTaskSearch.h in Headers */ = {isa = PBXBuildFile; fileRef = D8370B6B273DF20F00F66E2D /* SentryNSURLSessionTaskSearch.h */; };
 		D84793262788737D00BE8E99 /* SentryByteCountFormatter.m in Sources */ = {isa = PBXBuildFile; fileRef = D84793242788737D00BE8E99 /* SentryByteCountFormatter.m */; };
 		D8479328278873A100BE8E99 /* SentryByteCountFormatter.h in Headers */ = {isa = PBXBuildFile; fileRef = D8479327278873A100BE8E99 /* SentryByteCountFormatter.h */; };
+		D84F833D2A1CC401005828E0 /* SentrySwiftAsyncIntegration.h in Headers */ = {isa = PBXBuildFile; fileRef = D84F833B2A1CC401005828E0 /* SentrySwiftAsyncIntegration.h */; };
+		D84F833E2A1CC401005828E0 /* SentrySwiftAsyncIntegration.m in Sources */ = {isa = PBXBuildFile; fileRef = D84F833C2A1CC401005828E0 /* SentrySwiftAsyncIntegration.m */; };
 		D85596F3280580F10041FF8B /* SentryScreenshotIntegration.m in Sources */ = {isa = PBXBuildFile; fileRef = D85596F1280580F10041FF8B /* SentryScreenshotIntegration.m */; };
 		D855AD62286ED6A4002573E1 /* SentryCrashTests.m in Sources */ = {isa = PBXBuildFile; fileRef = D855AD61286ED6A4002573E1 /* SentryCrashTests.m */; };
 		D855B3E827D652AF00BCED76 /* SentryCoreDataTrackingIntegrationTest.swift in Sources */ = {isa = PBXBuildFile; fileRef = D855B3E727D652AF00BCED76 /* SentryCoreDataTrackingIntegrationTest.swift */; };
@@ -1060,7 +1062,7 @@
 		63FE700720DA4C1000CDBAE8 /* SentryCrashDate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SentryCrashDate.h; sourceTree = "<group>"; };
 		63FE700820DA4C1000CDBAE8 /* SentryCrashMachineContext_Apple.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SentryCrashMachineContext_Apple.h; sourceTree = "<group>"; };
 		63FE700920DA4C1000CDBAE8 /* SentryCrashLogger.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SentryCrashLogger.c; sourceTree = "<group>"; };
-		63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SentryCrashStackCursor_SelfThread.c; sourceTree = "<group>"; };
+		63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; path = SentryCrashStackCursor_SelfThread.m; sourceTree = "<group>"; };
 		63FE700B20DA4C1000CDBAE8 /* SentryCrashFileUtils.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SentryCrashFileUtils.h; sourceTree = "<group>"; };
 		63FE700C20DA4C1000CDBAE8 /* SentryCrashMach.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SentryCrashMach.c; sourceTree = "<group>"; };
 		63FE700D20DA4C1000CDBAE8 /* SentryCrashStackCursor_MachineContext.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; path = SentryCrashStackCursor_MachineContext.c; sourceTree = "<group>"; };
@@ -1671,6 +1673,8 @@
 		D8370B6B273DF20F00F66E2D /* SentryNSURLSessionTaskSearch.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SentryNSURLSessionTaskSearch.h; path = include/SentryNSURLSessionTaskSearch.h; sourceTree = "<group>"; };
 		D84793242788737D00BE8E99 /* SentryByteCountFormatter.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryByteCountFormatter.m; sourceTree = "<group>"; };
 		D8479327278873A100BE8E99 /* SentryByteCountFormatter.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = SentryByteCountFormatter.h; path = include/SentryByteCountFormatter.h; sourceTree = "<group>"; };
+		D84F833B2A1CC401005828E0 /* SentrySwiftAsyncIntegration.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SentrySwiftAsyncIntegration.h; path = include/SentrySwiftAsyncIntegration.h; sourceTree = "<group>"; };
+		D84F833C2A1CC401005828E0 /* SentrySwiftAsyncIntegration.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentrySwiftAsyncIntegration.m; sourceTree = "<group>"; };
 		D85596F1280580F10041FF8B /* SentryScreenshotIntegration.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryScreenshotIntegration.m; sourceTree = "<group>"; };
 		D855AD61286ED6A4002573E1 /* SentryCrashTests.m */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.objc; path = SentryCrashTests.m; sourceTree = "<group>"; };
 		D855B3E727D652AF00BCED76 /* SentryCoreDataTrackingIntegrationTest.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SentryCoreDataTrackingIntegrationTest.swift; sourceTree = "<group>"; };
@@ -2436,7 +2440,7 @@
 				63FE702B20DA4C1000CDBAE8 /* SentryCrashStackCursor_Backtrace.h */,
 				63FE700D20DA4C1000CDBAE8 /* SentryCrashStackCursor_MachineContext.c */,
 				63FE703120DA4C1000CDBAE8 /* SentryCrashStackCursor_MachineContext.h */,
-				63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.c */,
+				63FE700A20DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.m */,
 				63FE702620DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.h */,
 				63FE703B20DA4C1000CDBAE8 /* SentryCrashStackCursor.c */,
 				63FE701C20DA4C1000CDBAE8 /* SentryCrashStackCursor.h */,
@@ -2799,6 +2803,8 @@
 				7BCFBD6E2681D0EE00BC27D8 /* SentryCrashScopeObserver.m */,
 				7B96571F26830C9100C66E25 /* SentryScopeSyncC.h */,
 				7B96572126830D2400C66E25 /* SentryScopeSyncC.c */,
+				D84F833B2A1CC401005828E0 /* SentrySwiftAsyncIntegration.h */,
+				D84F833C2A1CC401005828E0 /* SentrySwiftAsyncIntegration.m */,
 			);
 			name = SentryCrash;
 			sourceTree = "<group>";
@@ -3445,6 +3451,7 @@
 				7B98D7E425FB7A7200C5A389 /* SentryAppState.h in Headers */,
 				7BDEAA022632A4580001EA25 /* SentryOptions+Private.h in Headers */,
 				A8AFFCCD29069C3E00967CD7 /* SentryHttpStatusCodeRange.h in Headers */,
+				D84F833D2A1CC401005828E0 /* SentrySwiftAsyncIntegration.h in Headers */,
 				15E0A8EA240F2C9000F044E3 /* SentrySerialization.h in Headers */,
 				63FE70EF20DA4C1000CDBAE8 /* SentryCrashMonitor_AppState.h in Headers */,
 				635B3F381EBC6E2500A6176D /* SentryAsynchronousOperation.h in Headers */,
@@ -3898,6 +3905,7 @@
 				7B8713B426415BAA006D6004 /* SentryAppStartTracker.m in Sources */,
 				7BDB03BB2513652900BAE198 /* SentryDispatchQueueWrapper.m in Sources */,
 				7B6C5EDE264E8DF00010D138 /* SentryFramesTracker.m in Sources */,
+				D84F833E2A1CC401005828E0 /* SentrySwiftAsyncIntegration.m in Sources */,
 				7B6438AB26A70F24000D0F65 /* UIViewController+Sentry.m in Sources */,
 				63AA76A31EB9CBAA00D153DE /* SentryDsn.m in Sources */,
 				63B818FA1EC34639002FDF4C /* SentryDebugMeta.m in Sources */,
@@ -3974,7 +3982,7 @@
 				D8F6A2472885512100320515 /* SentryPredicateDescriptor.m in Sources */,
 				A839D89A24864BA8003B7AFD /* SentrySystemEventBreadcrumbs.m in Sources */,
 				7D082B8323C628790029866B /* SentryMeta.m in Sources */,
-				63FE710720DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.c in Sources */,
+				63FE710720DA4C1000CDBAE8 /* SentryCrashStackCursor_SelfThread.m in Sources */,
 				63FE711120DA4C1000CDBAE8 /* SentryCrashDebug.c in Sources */,
 				7B883F49253D714C00879E62 /* SentryCrashUUIDConversion.c in Sources */,
 				63FE716720DA4C1100CDBAE8 /* SentryCrashCPU.c in Sources */,

Sources/Sentry/Public/SentryOptions.h

@@ -482,6 +482,12 @@ NS_SWIFT_NAME(Options)
  */
 @property (nonatomic) BOOL enableTimeToFullDisplay;
 
+/**
+ * @warning This is an experimental feature and may still have bugs.
+ * @brief Stitches the call to Swift Async functions in one consecutive stack trace.
+ * @note Default value is @c NO .
+ */
+@property (nonatomic, assign) BOOL swiftAsyncStacktraces;
 @end
 
 NS_ASSUME_NONNULL_END

Sources/Sentry/SentryOptions.m

@@ -43,7 +43,8 @@ - (void)setMeasurement:(SentryMeasurementValue *)measurement
             @"SentryAutoBreadcrumbTrackingIntegration", @"SentryAutoSessionTrackingIntegration",
             @"SentryAppStartTrackingIntegration", @"SentryWatchdogTerminationTrackingIntegration",
             @"SentryPerformanceTrackingIntegration", @"SentryNetworkTrackingIntegration",
-            @"SentryFileIOTrackingIntegration", @"SentryCoreDataTrackingIntegration"
+            @"SentryFileIOTrackingIntegration", @"SentryCoreDataTrackingIntegration",
+            @"SentrySwiftAsyncIntegration"
         ]
             .mutableCopy;
 
@@ -106,6 +107,7 @@ - (instancetype)init
         self.enableCoreDataTracing = YES;
         _enableSwizzling = YES;
         self.sendClientReports = YES;
+        self.swiftAsyncStacktraces = NO;
 
 #if TARGET_OS_OSX
         NSString *dsn = [[[NSProcessInfo processInfo] environment] objectForKey:@"SENTRY_DSN"];
@@ -315,6 +317,9 @@ - (BOOL)validateOptions:(NSDictionary<NSString *, id> *)options
     [self setBool:options[@"enableWatchdogTerminationTracking"]
             block:^(BOOL value) { self->_enableWatchdogTerminationTracking = value; }];
 
+    [self setBool:options[@"swiftAsyncStacktraces"]
+            block:^(BOOL value) { self->_swiftAsyncStacktraces = value; }];
+
     if ([options[@"sessionTrackingIntervalMillis"] isKindOfClass:[NSNumber class]]) {
         self.sessionTrackingIntervalMillis =
             [options[@"sessionTrackingIntervalMillis"] unsignedIntValue];

Sources/Sentry/SentrySwiftAsyncIntegration.m

@@ -0,0 +1,17 @@
+#import "SentrySwiftAsyncIntegration.h"
+#import "SentryCrashStackCursor_SelfThread.h"
+
+@implementation SentrySwiftAsyncIntegration
+
+- (BOOL)installWithOptions:(nonnull SentryOptions *)options
+{
+    sentrycrashsc_setSwiftAsyncStitching(options.swiftAsyncStacktraces);
+    return options.swiftAsyncStacktraces;
+}
+
+- (void)uninstall
+{
+    sentrycrashsc_setSwiftAsyncStitching(NO);
+}
+
+@end

Sources/Sentry/include/SentrySwiftAsyncIntegration.h

@@ -0,0 +1,11 @@
+#import "SentryBaseIntegration.h"
+#import "SentryIntegrationProtocol.h"
+#import <Foundation/Foundation.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface SentrySwiftAsyncIntegration : SentryBaseIntegration <SentryIntegrationProtocol>
+
+@end
+
+NS_ASSUME_NONNULL_END

Sources/SentryCrash/Recording/Tools/SentryCrashStackCursor_SelfThread.h

@@ -42,6 +42,8 @@ extern "C" {
  */
 void sentrycrashsc_initSelfThread(SentryCrashStackCursor *cursor, int skipEntries);
 
+void sentrycrashsc_setSwiftAsyncStitching(bool enabled);
+
 #ifdef __cplusplus
 }
 #endif

Sources/SentryCrash/Recording/Tools/SentryCrashStackCursor_SelfThread.c renamed to Sources/SentryCrash/Recording/Tools/SentryCrashStackCursor_SelfThread.m

@@ -39,10 +39,35 @@ typedef struct {
     uintptr_t backtrace[0];
 } SelfThreadContext;
 
+static BOOL stitchSwiftAsync = NO;
+
+void
+sentrycrashsc_setSwiftAsyncStitching(bool enabled)
+{
+    stitchSwiftAsync = enabled;
+}
+
 void
 sentrycrashsc_initSelfThread(SentryCrashStackCursor *cursor, int skipEntries)
 {
     SelfThreadContext *context = (SelfThreadContext *)cursor->context;
+
+// backtrace_async api is only available from xcode 13
+#if __clang_major__ >= 13
+    int backtraceLength;
+    if (@available(macOS 12.0, iOS 15.0, tvOS 15.0, watchOS 8.0, *)) {
+        if (stitchSwiftAsync) {
+            backtraceLength
+                = (int)backtrace_async((void **)context->backtrace, MAX_BACKTRACE_LENGTH, NULL);
+        } else {
+            backtraceLength = backtrace((void **)context->backtrace, MAX_BACKTRACE_LENGTH);
+        }
+    } else {
+        backtraceLength = backtrace((void **)context->backtrace, MAX_BACKTRACE_LENGTH);
+    }
+#else
     int backtraceLength = backtrace((void **)context->backtrace, MAX_BACKTRACE_LENGTH);
+#endif
+
     sentrycrashsc_initWithBacktrace(cursor, context->backtrace, backtraceLength, skipEntries + 1);
 }

Tests/SentryTests/SentryCrash/SentryStacktraceBuilderTests.swift

@@ -67,7 +67,63 @@ class SentryStacktraceBuilderTests: XCTestCase {
 
         XCTAssertTrue(filteredFrames.count == 1, "The frames must be ordered from caller to callee, or oldest to youngest.")
     }
-     
+
+    func testConcurrentStacktraces() {
+        guard #available(macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0, *) else { return }
+
+        SentrySDK.start { options in
+            options.dsn = TestConstants.dsnAsString(username: "SentryStacktraceBuilderTests")
+            options.swiftAsyncStacktraces = true
+        }
+
+        let waitForAsyncToRun = expectation(description: "Wait async functions")
+        Task {
+            let filteredFrames = await self.firstFrame()
+            waitForAsyncToRun.fulfill()
+            XCTAssertGreaterThanOrEqual(filteredFrames, 3, "The Stacktrace must include the async callers.")
+        }
+        wait(for: [waitForAsyncToRun], timeout: 1)
+    }
+
+    func testConcurrentStacktraces_noStitching() {
+        guard #available(macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0, *) else { return }
+
+        SentrySDK.start { options in
+            options.dsn = TestConstants.dsnAsString(username: "SentryStacktraceBuilderTests")
+            options.swiftAsyncStacktraces = false
+        }
+
+        let waitForAsyncToRun = expectation(description: "Wait async functions")
+        Task {
+            let filteredFrames = await self.firstFrame()
+            waitForAsyncToRun.fulfill()
+            XCTAssertGreaterThanOrEqual(filteredFrames, 1, "The Stacktrace must have only one function.")
+        }
+        wait(for: [waitForAsyncToRun], timeout: 1)
+    }
+
+    @available(macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0, *)
+    func firstFrame() async -> Int {
+        return await innerFrame1()
+    }
+
+    @available(macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0, *)
+    func innerFrame1() async -> Int {
+        await Task { @MainActor in }.value
+        return await innerFrame2()
+    }
+
+    @available(macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0, *)
+    func innerFrame2() async -> Int {
+        let needed = ["firstFrame", "innerFrame1", "innerFrame2"]
+        let actual = fixture.sut.buildStacktraceForCurrentThreadAsyncUnsafe()!
+        let filteredFrames = actual.frames
+            .compactMap({ $0.function })
+            .filter { needed.contains(where: $0.contains) }
+        return filteredFrames.count
+
+    }
+
     func asyncFrame1(expect: XCTestExpectation) {
         fixture.queue.asyncAfter(deadline: DispatchTime.now()) {
             self.asyncFrame2(expect: expect)