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Merged
bobleer merged 1 commit into from
Nov 9, 2026
Merged

fix(computer-use): stop macOS capture after resize failure #3842

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84 changes: 66 additions & 18 deletions scripts/fixtures/computer-use-capture.m
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Original file line number Diff line number Diff line change
@@ -1,17 +1,25 @@
#import <AppKit/AppKit.h>
#import <CoreMedia/CoreMedia.h>
#import <ScreenCaptureKit/ScreenCaptureKit.h>
#import <objc/runtime.h>
@interface NSObject (OBFCaptureTimingFixture)
@property(nonatomic) CMTime lastObservedSample;
@property(nonatomic) CMTime inputBarrier;
@end
#include <stdio.h>
#include <stdatomic.h>
// The native bridge distinguishes an unavailable surface from a stopped
// stream. Only status 1 initializes the frame and bounds output parameters.
static const int captureOK = 1;
static const int captureNoSurface = 2;
static atomic_bool stoppedWithIdentity;
static atomic_uint stopCount;
static uint32_t expectedWindow;
static uint64_t expectedGeneration = 1;
static atomic_uint_fast64_t expectedGeneration = 1;
static atomic_uint_fast64_t expectedRevision = UINT64_MAX;
extern uint32_t obf_capture_validate_target(int32_t, uint32_t, char *, size_t);
extern void *obf_capture_start(int32_t, uint32_t, uint64_t, char *, size_t);
extern void obf_capture_bind_revision(void *, uint64_t);
extern void obf_capture_mark_input(void *);
extern int obf_capture_bounds(void *, double *, char *, size_t);
extern int obf_capture_frame(void *, uint8_t **, size_t *, uint32_t *, uint32_t *, uint32_t *, double *, uint64_t *, char *, size_t);
Expand All @@ -21,9 +29,24 @@ @interface NSObject (OBFCaptureTimingFixture)
extern void obf_pointer_hide(void);
void obf_control_native_stopped(uint64_t generation, uint64_t revision, int32_t pid, uint32_t windowID, const char *reason) {
atomic_fetch_add(&stopCount, 1);
if(generation == expectedGeneration && pid == getpid() && windowID == expectedWindow) atomic_store(&stoppedWithIdentity, true);
if (generation == expectedGeneration && revision == expectedRevision &&
pid == getpid() && windowID == expectedWindow) atomic_store(&stoppedWithIdentity, true);
fprintf(stderr, "Stopped: %s\n", reason);
}
// Force an error from the reconfiguration completion while the real stream
// is still live. The control owner must be notified before explicit Stop.
static void rejectResize(id stream, SEL selector, SCStreamConfiguration *config, void (^completion)(NSError *)) {
completion([NSError errorWithDomain:@"OpenBitFunCaptureFixture" code:1
userInfo:@{NSLocalizedDescriptionKey: @"Fixture resize rejected"}]);
}
static BOOL windowIDStillExists(uint32_t windowID) {
CFArrayRef windows = CGWindowListCopyWindowInfo(kCGWindowListOptionAll, kCGNullWindowID);
for (NSDictionary *window in CFBridgingRelease(windows)) {
if ([window[(id)kCGWindowNumber] unsignedIntValue] == windowID &&
[window[(id)kCGWindowOwnerPID] intValue] == getpid()) return YES;
}
return NO;
}
// Opt-in diagnostic for a real application: only reads captured frames and
// prints window identity/geometry. No pixels are persisted and no input is sent.
static void observeApp(pid_t pid) {
Expand All @@ -34,7 +57,7 @@ static void observeApp(pid_t pid) {
int result=0; uint32_t bound=0;
for(int i=0;i<20;i++){
uint8_t *bytes=NULL;size_t length=0;uint32_t w=0,ht=0,wid=0;double bounds[4]={0};uint64_t sequence=0;
if(!obf_capture_frame(h,&bytes,&length,&w,&ht,&wid,bounds,&sequence,error,sizeof(error))){fprintf(stderr,"FRAME_ERROR %s\n",error);result=1;break;}
if(obf_capture_frame(h,&bytes,&length,&w,&ht,&wid,bounds,&sequence,error,sizeof(error)) != captureOK){fprintf(stderr,"FRAME_ERROR %s\n",error);result=1;break;}
if(i==0)bound=wid;
if(wid!=bound || atomic_load(&stopCount)){result=1;break;}
obf_capture_free(bytes);
Expand Down Expand Up @@ -82,9 +105,10 @@ int main(int argc, const char **argv) { @autoreleasepool {
return 0;
}
BOOL minimize = argc > 1 && strcmp(argv[1], "--minimized") == 0;
BOOL rejectConfiguration = argc > 1 && strcmp(argv[1], "--resize-error") == 0;
NSApplication *app = NSApplication.sharedApplication;
[app setActivationPolicy:NSApplicationActivationPolicyAccessory];
NSWindow *target = [[NSWindow alloc] initWithContentRect:NSMakeRect(100,100,240,160) styleMask:(minimize ? NSWindowStyleMaskTitled | NSWindowStyleMaskMiniaturizable : NSWindowStyleMaskBorderless) backing:NSBackingStoreBuffered defer:NO];
__block NSWindow *target = [[NSWindow alloc] initWithContentRect:NSMakeRect(100,100,240,160) styleMask:(minimize ? NSWindowStyleMaskTitled | NSWindowStyleMaskMiniaturizable : NSWindowStyleMaskBorderless) backing:NSBackingStoreBuffered defer:NO];
target.backgroundColor = NSColor.redColor;
target.releasedWhenClosed = NO;
[target orderFront:nil];
Expand All @@ -99,9 +123,29 @@ int main(int argc, const char **argv) { @autoreleasepool {
void *handle = obf_capture_start(getpid(), targetID, 1, error, sizeof(error));
int result = 1;
if (!handle) fprintf(stderr,"FAIL start: %s\n",error);
else {
else if (rejectConfiguration) {
expectedRevision = 4;
obf_capture_bind_revision(handle, expectedRevision);
Method update = class_getInstanceMethod(SCStream.class, @selector(updateConfiguration:completionHandler:));
IMP original = method_setImplementation(update, (IMP)rejectResize);
dispatch_sync(dispatch_get_main_queue(), ^{
[target setFrame:NSMakeRect(100,100,280,190) display:YES];
});
[NSThread sleepForTimeInterval:0.15];
uint8_t *bytes = NULL; size_t length = 0;
uint32_t width = 0, height = 0, windowID = 0; uint64_t sequence = 0; double bounds[4] = {0};
int status = obf_capture_frame(handle, &bytes, &length, &width, &height, &windowID, bounds, &sequence, error, sizeof(error));
method_setImplementation(update, original);
if (status == 0 && !bytes && atomic_load(&stoppedWithIdentity) &&
strstr(error, "CAPTURE_STOPPED:") && strstr(error, "Fixture resize rejected")) {
puts("PASS failed resize revokes the live capture before explicit Stop");
result = 0;
} else fprintf(stderr, "FAIL resize failure did not revoke capture: status=%d error=%s\n", status, error);
obf_capture_free(bytes);
obf_capture_stop(handle);
} else {
uint8_t *bytes = NULL; size_t length=0; uint32_t width=0,height=0,windowID=0; uint64_t sequence=0; double bounds[4]={0};
if (!obf_capture_frame(handle,&bytes,&length,&width,&height,&windowID,bounds,&sequence,error,sizeof(error))) fprintf(stderr,"FAIL frame: %s\n",error);
if (obf_capture_frame(handle,&bytes,&length,&width,&height,&windowID,bounds,&sequence,error,sizeof(error)) != captureOK) fprintf(stderr,"FAIL frame: %s\n",error);
else {
size_t center = ((height/2)*width + width/2)*4;
printf("Frame %ux%u target=%u returned=%u sequence=%llu center RGBA=%u,%u,%u,%u bounds=%.0f,%.0f,%.0f,%.0f\n",width,height,targetID,windowID,sequence,bytes[center],bytes[center+1],bytes[center+2],bytes[center+3],bounds[0],bounds[1],bounds[2],bounds[3]);
Expand All @@ -116,8 +160,8 @@ int main(int argc, const char **argv) { @autoreleasepool {
uint8_t *fresh = NULL; size_t freshLength = 0;
uint32_t freshWidth = 0, freshHeight = 0, freshWindow = 0;
uint64_t freshSequence = 0; double freshBounds[4] = {0};
if (!obf_capture_frame(handle, &fresh, &freshLength, &freshWidth, &freshHeight,
&freshWindow, freshBounds, &freshSequence, error, sizeof(error)) ||
if (obf_capture_frame(handle, &fresh, &freshLength, &freshWidth, &freshHeight,
&freshWindow, freshBounds, &freshSequence, error, sizeof(error)) != captureOK ||
CMTimeCompare([(__bridge id)handle lastObservedSample], barrier) < 0) {
fprintf(stderr, "FAIL capture returned a pre-input sample: %s\n", error); result = 1;
} else puts("PASS post-input observation waits for a newer complete or idle sample");
Expand All @@ -132,8 +176,8 @@ int main(int argc, const char **argv) { @autoreleasepool {
uint8_t *repeat = NULL; size_t repeatLength = 0;
uint32_t repeatWidth = 0, repeatHeight = 0, repeatWindow = 0;
uint64_t repeatSequence = 0; double repeatBounds[4] = {0};
if (!obf_capture_frame(handle, &repeat, &repeatLength, &repeatWidth, &repeatHeight,
&repeatWindow, repeatBounds, &repeatSequence, error, sizeof(error)) ||
if (obf_capture_frame(handle, &repeat, &repeatLength, &repeatWidth, &repeatHeight,
&repeatWindow, repeatBounds, &repeatSequence, error, sizeof(error)) != captureOK ||
repeatWindow != targetID || atomic_load(&stoppedWithIdentity)) {
fprintf(stderr, "FAIL persistent observation %d: %s\n", observation, error); result = 1;
}
Expand Down Expand Up @@ -171,21 +215,21 @@ int main(int argc, const char **argv) { @autoreleasepool {
dispatch_sync(dispatch_get_main_queue(), ^{ [target setFrameOrigin:NSMakePoint(110,100)]; });
[NSThread sleepForTimeInterval:0.15]; // WindowServer commits the AppKit geometry asynchronously.
double inputBounds[4] = {0};
if (!obf_capture_bounds(handle, inputBounds, error, sizeof(error)) || inputBounds[0] != 110) {
if (obf_capture_bounds(handle, inputBounds, error, sizeof(error)) != captureOK || inputBounds[0] != 110) {
fprintf(stderr,"FAIL input-only geometry retained stale origin: %s\n",error); result=1;
} else puts("PASS input geometry updates after movement without copying or encoding a frame");
uint8_t *movedBytes = NULL; size_t movedLength = 0;
uint32_t movedWidth=0,movedHeight=0,movedWindow=0; uint64_t movedSequence=0; double movedBounds[4]={0};
int moved = obf_capture_frame(handle,&movedBytes,&movedLength,&movedWidth,&movedHeight,&movedWindow,movedBounds,&movedSequence,error,sizeof(error));
if (!moved || movedBounds[0] != 110) {
if (moved != captureOK || movedBounds[0] != 110) {
fprintf(stderr,"FAIL moved geometry not refreshed: %s\n",error); result=1;
} else puts("PASS moved window returns the new coordinate basis");
if(movedBytes) obf_capture_free(movedBytes);
dispatch_sync(dispatch_get_main_queue(), ^{ [target setFrame:NSMakeRect(110,100,280,190) display:YES]; });
[NSThread sleepForTimeInterval:0.15];
movedBytes = NULL;
int resized = obf_capture_frame(handle,&movedBytes,&movedLength,&movedWidth,&movedHeight,&movedWindow,movedBounds,&movedSequence,error,sizeof(error));
if (!resized || movedWidth != 280 || movedHeight != 190 || movedBounds[2] != 280 || movedBounds[3] != 190) {
if (resized != captureOK || movedWidth != 280 || movedHeight != 190 || movedBounds[2] != 280 || movedBounds[3] != 190) {
fprintf(stderr,"FAIL resized stream did not produce matching pixels: %s\n",error); result=1;
} else puts("PASS resized window updates SCStream and waits for matching frame dimensions");
if(movedBytes) obf_capture_free(movedBytes);
Expand All @@ -196,9 +240,8 @@ int main(int argc, const char **argv) { @autoreleasepool {
uint8_t *hiddenBytes = NULL; size_t hiddenLength = 0;
uint32_t hiddenWidth=0,hiddenHeight=0,hiddenWindow=0; uint64_t hiddenSequence=0; double hiddenBounds[4]={0};
int hidden = obf_capture_frame(handle,&hiddenBytes,&hiddenLength,&hiddenWidth,&hiddenHeight,&hiddenWindow,hiddenBounds,&hiddenSequence,error,sizeof(error));
if (hidden) {
size_t center = ((hiddenHeight/2)*hiddenWidth+hiddenWidth/2)*4;
fprintf(stderr,"HIDDEN frame center after changing background to green: %u,%u,%u\n",hiddenBytes[center],hiddenBytes[center+1],hiddenBytes[center+2]);
if (hidden == captureOK || hiddenBytes) {
fprintf(stderr,"FAIL hidden target returned a frame\n");
result = 1;
obf_capture_free(hiddenBytes);
} else if (!strstr(error,"TARGET_")) {
Expand All @@ -214,12 +257,17 @@ int main(int argc, const char **argv) { @autoreleasepool {
if(!handle) { fprintf(stderr,"FAIL restored target restart: %s\n",error); result=1; }
}
if (result == 0) {
dispatch_sync(dispatch_get_main_queue(), ^{ [target close]; });
// A retained NSWindow can keep its WindowServer ID after
// close. Release it so this exercises loss of the window.
dispatch_sync(dispatch_get_main_queue(), ^{ [target close]; target = nil; });
[NSThread sleepForTimeInterval:0.2];
uint8_t *closedBytes = NULL; size_t closedLength = 0;
uint32_t closedWidth=0,closedHeight=0,closedWindow=0; uint64_t closedSequence=0; double closedBounds[4]={0};
int closed = obf_capture_frame(handle,&closedBytes,&closedLength,&closedWidth,&closedHeight,&closedWindow,closedBounds,&closedSequence,error,sizeof(error));
if (closed || !atomic_load(&stoppedWithIdentity)) {
if (closed == captureNoSurface && !closedBytes &&
strstr(error, "TARGET_SURFACE_UNAVAILABLE:") && windowIDStillExists(targetID)) {
puts("PASS AppKit retained the closed window ID and capture returned no pixels");
} else if (closed != 0 || closedBytes || !atomic_load(&stoppedWithIdentity)) {
fprintf(stderr,"FAIL closed target did not revoke capture with its identity: %s\n",error); result=1;
} else puts("PASS closed window revokes capture with its original generation and target");
if(closedBytes) obf_capture_free(closedBytes);
Expand Down
1 change: 1 addition & 0 deletions scripts/test-macos-control-capture.mjs
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Original file line number Diff line number Diff line change
Expand Up @@ -31,6 +31,7 @@ try {
} else {
await run(binary, []);
await run(binary, ['--minimized']);
await run(binary, ['--resize-error']);
}
} finally {
await rm(directory, { recursive: true, force: true });
Expand Down
31 changes: 20 additions & 11 deletions src/crates/services/computer-use/src/computer_use/macos_capture.m
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -218,24 +218,33 @@ - (instancetype)init {
}
return self;
}
- (void)fail:(NSString *)reason {
- (BOOL)fail:(NSString *)reason {
[self.condition lock];
if (self.stopped) {
[self.condition unlock];
return NO;
}
self.stopped = YES;
self.failure = reason ?: @"Capture stopped";
self.pixels = nil;
[self.condition broadcast];
[self.condition unlock];
obf_focus_loss_stop_matching(self.pid, self.windowID, self.generation, false, 0, 0);
return YES;
}
- (void)reportTerminalFailure:(NSString *)reason {
if (![self fail:reason]) return;
// A failed stream must also revoke its control binding. The owner tears
// down the matching stream asynchronously, outside the capture lock.
obf_control_native_stopped(self.generation, self.targetRevision, self.pid, self.windowID, reason.UTF8String);
}
- (void)stream:(SCStream *)stream didStopWithError:(NSError *)error {
[self fail:[NSString stringWithFormat:@"CAPTURE_STOPPED: %@", error.localizedDescription]];
obf_control_native_stopped(self.generation, self.targetRevision, self.pid, self.windowID, self.failure.UTF8String);
[self reportTerminalFailure:[NSString stringWithFormat:@"CAPTURE_STOPPED: %@", error.localizedDescription]];
}
// macOS 15.2+: a closed target must immediately revoke input, even if the
// framework keeps the stream available for a later reopened window.
- (void)streamDidBecomeInactive:(SCStream *)stream {
[self fail:@"TARGET_WINDOW_UNAVAILABLE: Shared window became inactive"];
obf_control_native_stopped(self.generation, self.targetRevision, self.pid, self.windowID, self.failure.UTF8String);
[self reportTerminalFailure:@"TARGET_WINDOW_UNAVAILABLE: Shared window became inactive"];
[stream stopCaptureWithCompletionHandler:^(NSError *error) { (void)error; }];
}
- (void)stream:(SCStream *)stream didOutputSampleBuffer:(CMSampleBufferRef)sample ofType:(SCStreamOutputType)type {
Expand Down Expand Up @@ -548,8 +557,7 @@ uint32_t obf_capture_default_window(int32_t pid, char *error, size_t capacity) {
int obf_capture_status(void *handle, char *error, size_t capacity) {
OBFWindowCapture *session = (__bridge OBFWindowCapture *)handle;
if (obf_session_locked()) {
[session fail:@"SESSION_LOCKED: Execution host screen is locked; start control again after unlocking"];
obf_control_native_stopped(session.generation, session.targetRevision, session.pid, session.windowID, session.failure.UTF8String);
[session reportTerminalFailure:@"SESSION_LOCKED: Execution host screen is locked; start control again after unlocking"];
[session.stream stopCaptureWithCompletionHandler:^(NSError *e) { (void)e; }];
obf_error(error, capacity, session.failure);
return 0;
Expand All @@ -561,8 +569,7 @@ int obf_capture_status(void *handle, char *error, size_t capacity) {
BOOL wasStopped = session.stopped;
[session.condition unlock];
if (!wasStopped && !valid) {
[session fail:@"TARGET_WINDOW_UNAVAILABLE: Original target window was closed"];
obf_control_native_stopped(session.generation, session.targetRevision, session.pid, session.windowID, session.failure.UTF8String);
[session reportTerminalFailure:@"TARGET_WINDOW_UNAVAILABLE: Original target window was closed"];
[session.stream stopCaptureWithCompletionHandler:^(NSError *e) { (void)e; }];
}
[session.condition lock];
Expand Down Expand Up @@ -689,7 +696,7 @@ int obf_capture_frame(void *handle, uint8_t **bytes, size_t *length, uint32_t *w
CGRect frame = CGRectZero;
BOOL onScreen = NO;
if (!obf_window_info(session.pid, session.windowID, &frame, &onScreen)) {
[session fail:@"TARGET_WINDOW_UNAVAILABLE: Original target window was closed"];
[session reportTerminalFailure:@"TARGET_WINDOW_UNAVAILABLE: Original target window was closed"];
}
[session.condition lock];
if (session.stopped) {
Expand All @@ -710,7 +717,9 @@ int obf_capture_frame(void *handle, uint8_t **bytes, size_t *length, uint32_t *w
SCStreamConfiguration *configuration = session.configuration;
[session.condition unlock];
[session.stream updateConfiguration:configuration completionHandler:^(NSError *updateError) {
if (updateError) [session fail:updateError.localizedDescription];
if (updateError) {
[session reportTerminalFailure:[NSString stringWithFormat:@"CAPTURE_STOPPED: Window capture resize failed: %@", updateError.localizedDescription]];
}
}];
[session.condition lock];
}
Expand Down
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