Function TryFindCCMInterface

src/platform/win/cloud_intercept.cpp:1035–1091

Try to find CCMInterface if not yet found. Called from OnSendPkt on each invocation until successful. Once found, g_cmInterface is stable for the session.

// Try to find CCMInterface if not yet found. Called from OnSendPkt on each invocation
// until successful. Once found, g_cmInterface is stable for the session.
static void TryFindCCMInterface() {
    if (g_cmInterfaceFound.load(std::memory_order_acquire)) return;

    void* ccm = FindCCMInterface();
    if (!ccm) return;

    // Claim first-finder atomically. Write pointer before flag (release ordering).
    bool expected = false;
    g_cmInterface.store(ccm, std::memory_order_release);
    if (!g_cmInterfaceFound.compare_exchange_strong(expected, true,
            std::memory_order_acq_rel, std::memory_order_acquire)) {
        return; // another thread already found it
    }

    LOG("[CCM] Found real CCMInterface: %p", ccm);

    // Log details for debugging (wrapped in SEH - raw pointer dereferences for diagnostics only)
    __try {
        uintptr_t* pEngineGlobal = (uintptr_t*)SC_RESOLVE(globalEngine);
        uintptr_t engine = *pEngineGlobal;
        uint32_t handle = *(uint32_t*)(engine + ENGINE_OFF_GLOBAL_HANDLE);

        LOG("[CCM]   CSteamEngine: %p (global at sc+0x%X)", (void*)engine, SC_RVA_GLOBAL_ENGINE);
        LOG("[CCM]   Global user handle: %u", handle);
        LOG("[CCM]   Vtable: %p (RVA=0x%llX) -- MATCHES CCMInterface::vftable",
            (void*)(*(uintptr_t*)ccm), (uint64_t)SC_RVA_CCMINTERFACE_VT);
    } __except(EXCEPTION_EXECUTE_HANDLER) {
        LOG("[CCM] WARNING: exception reading engine globals (code=0x%lX)", GetExceptionCode());
    }

    // Resolve BRouteMsgToJob bypass function pointers (computed from base + RVA, no dereferences)
    g_wrapPacket     = (WrapPacketFn)SC_RESOLVE(wrapPacket);
    g_bRouteMsgToJob = (BRouteMsgToJobFn)SC_RESOLVE(bRouteMsgToJob);
    g_releaseWrapped = (ReleaseWrappedFn)SC_RESOLVE(releaseWrapped);
    g_refCountHelper = (RefCountHelperFn)SC_RESOLVE(refCountHelper);
    g_refCountGlobalPtr = (volatile int64_t**)SC_RESOLVE(refCountGlobal);
    LOG("[CCM]   WrapPacket=%p BRouteMsgToJob=%p ReleaseWrapped=%p",
        g_wrapPacket, g_bRouteMsgToJob, g_releaseWrapped);

    // Additional diagnostic logging (dereferences pointers, wrap in SEH)
    __try {
        LOG("[CCM]   RefCountHelper=%p RefCountGlobal=%p (*=%p)",
            g_refCountHelper, g_refCountGlobalPtr,
            g_refCountGlobalPtr ? (void*)*g_refCountGlobalPtr : nullptr);
        uintptr_t engine = *(uintptr_t*)SC_RESOLVE(globalEngine);
        LOG("[CCM]   CJobMgr (engine+%u)=%p  ConnCtx (ccm+%u)=%p",
            ENGINE_OFF_JOBMGR, (void*)(engine + ENGINE_OFF_JOBMGR),
            CCM_OFF_CONN_CONTEXT, *(void**)((uintptr_t)ccm + CCM_OFF_CONN_CONTEXT));
    } __except(EXCEPTION_EXECUTE_HANDLER) {
        LOG("[CCM] WARNING: exception during extended diagnostics (code=0x%lX)", GetExceptionCode());
    }

    // Install service-method vtable hook (Approach E) now that we have steamclient base
    if (!g_vtableHookInstalled.load(std::memory_order_acquire) && HasNamespaceApps()) {
        InstallServiceMethodHook();
    }
}