Method CallGuard

src/platform/linux/schema_fetch.cpp:119–129

class CallGuard {
public:
    CallGuard() {
        struct sigaction sa = {};
        sa.sa_handler = CrashHandler;
        sigemptyset(&sa.sa_mask);
        sa.sa_flags = SA_RESETHAND;
        sigaction(SIGSEGV, &sa, &m_segv);
        sigaction(SIGBUS, &sa, &m_bus);
        // Don't trap SIGABRT: it fires async on the CM thread after this guard dies;
        // let init.cpp's CrashDumpHandler own it.
        g_inCall = 1;
    }
    ~CallGuard() {
        g_inCall = 0;
        sigaction(SIGSEGV, &m_segv, nullptr);