Spamming a subsystem toggle (the "Mirror video" button) could crash the game:
remove_*_hooks freed a hook's shared D3D / Vulkan / IPC state immediately, while a
capture detour was still mid-flight on the game's render thread -> use-after-free.
Only the audio hooks had the safe-unhook drain; the video (Present/D3D9/D3D10/GL/
Vulkan) and XInput/focus/MKB hooks did not.
Test-first: mock_game_test now runs an aggressive hook/unhook storm -- a separate
thread thrashes every subsystem on/off while the game presents, across all backends.
It crashed gl + vk (0xC0000005) and failed dx9 capture-resume before the fix.
Fix (hook/src/hook_guard.hpp, DetourGate): each detour wraps its body in an RAII
active-count Guard; remove_* restores the hook first (so no new detour starts),
drains the in-flight detours to zero, and only then frees the shared state. Vulkan
is special-cased -- the game caches hk_vkQueuePresentKHR, so removal closes an
atomic capture gate (detours then pass through to the real present), drains, then
frees the read-back resources. Storm now passes on every backend.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
BlackMark
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