Method inferTidFromPThreadStructure

src/pystack/_pystack/pythread.cpp:176–211

}

int
PyThread::inferTidFromPThreadStructure(
        const std::shared_ptr<const AbstractProcessManager>& manager,
        unsigned long pthread_id)
{
    // There is not a simple way of getting the Thread ID (tid) used by the OS
    // given the pthread_id (thread_id) that we just got from the remote process.
    // Turns out that the pthread id is just the address of the pthread struct
    // that is used to create the thread in the pthread library (this fact is used
    // by gdb and other debuggers). This struct contains the tid inside so we just
    // need to know the offset in this struct. The struct looks like this (from
    // glibc):
    //
    // struct pthread {
    //    union
    //    {
    //        tcbhead_t header;
    //        void *__padding[24];
    //    };
    //    list_t list;
    //    pid_t tid;
    //   ...
    //   }
    //
    int the_tid;
    manager->copyObjectFromProcess((remote_addr_t)(pthread_id + tid_offset_in_pthread_struct), &the_tid);

    // To double check that this number is correct, we then check that this is one
    // of the tids that we know. A thread id of 0 means that the thread was terminated
    // but not joined.
    const auto& tids = manager->Tids();
    if (the_tid != 0 && std::find(tids.begin(), tids.end(), the_tid) == tids.end()) {
        throw std::runtime_error("Invalid thread ID found!");
    }
    return the_tid;
}

remote_addr_t
PyThread::getFrameAddr(