Fix dock-swipe gestures broken on macOS 27 #1924
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…ed CGEvent offsets CGEventSetIOHIDEvent() attaches an IOHIDEvent to a CGEvent by poking the pointer into the opaque CGEvent/CGSEventRecord struct at hardcoded offsets (0x18 / 0xd0). Those offsets were never a stable ABI, and the struct layout shifted on macOS 27, so the pointer ends up at the wrong address and Dock never sees a real IOHIDEvent - which is why every synthetic dock-swipe gesture (Spaces, Mission Control, Show Desktop, Launchpad) silently stopped doing anything. See noah-nuebling#1871 and the pile of duplicates (noah-nuebling#1873, noah-nuebling#1878, noah-nuebling#1887, noah-nuebling#1891, noah-nuebling#1892, noah-nuebling#1919, ...). Now prefers Apple's own SLEventSetIOHIDEvent, resolved once via the project's existing MFLoadSymbol_native(kMFFrameworkSkyLight, ...) helper (Shared/Utility/PrivateFunctions) instead of a hand-rolled dlsym call. Also retains the IOHIDEventRef on this path, same as the old offset-writer did, since SLEventSetIOHIDEvent's retain contract isn't documented and an extra retain is safer than an under-retain. The offset-writer is kept as a fallback only for pre-macOS-27, where it was actually validated - on 27+ it's skipped instead of executed, since those offsets are already known to be wrong there and running it would provide no real safety net, just continued exposure to writing an unvalidated address. Tested on macOS 27 - Spaces/Mission Control/Show Desktop click-and-drag all work again after this. Same root cause as noah-nuebling#1920, noah-nuebling#1912, noah-nuebling#1916 (also switch to SLEventSetIOHIDEvent); related to noah-nuebling#1895, noah-nuebling#1918.
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Fixes #1871 and the duplicates (#1873, #1878, #1887, #1891, #1892, #1919, ...).
Problem
CGEventSetIOHIDEvent()attaches an IOHIDEvent to a CGEvent by poking the pointer into the opaque CGEvent/CGSEventRecord struct at hardcoded offsets (0x18 / 0xd0). Those offsets were never a stable ABI, and the struct layout shifted on macOS 27, so the pointer ends up at the wrong address and Dock never sees a real IOHIDEvent - which is why every synthetic dock-swipe gesture (Spaces, Mission Control, Show Desktop, Launchpad) silently stopped doing anything.Fix
Prefers Apple's own
SLEventSetIOHIDEvent, resolved once via the project's existingMFLoadSymbol_native(kMFFrameworkSkyLight, ...)helper (Shared/Utility/PrivateFunctions). Falls back to the offset-writer only pre-macOS-27, where it was actually validated - on 27+ it's skipped instead of executed, since it's already known to be broken there.Notes
Same root cause and fix direction as #1920 / #1912 / #1916 (swap to
SLEventSetIOHIDEvent). A couple of things that came up while testing, in case they're useful:MFLoadSymbol_native/kMFFrameworkSkyLightinstead of hand-rolling adlsymcall.CFRetains theIOHIDEventRefon the new path, matching what the old offset-writer already did -SLEventSetIOHIDEvent's retain contract isn't documented anywhere, andTouchSimulator.mcan repost some dock-swipe events up to 500ms later via a timer, so skipping the retain risks a use-after-free if the event isn't retained internally.Testing
Tested on macOS 27 - Spaces/Mission Control/Show Desktop click-and-drag all work again after this.