#include "rust_internal.h"

#define KLOG_(...) \
    KLOG(this, kern, __VA_ARGS__)
#define KLOG_ERR_(field, ...)                    \
    KLOG_LVL(this, field, log_err, __VA_ARGS__)

rust_kernel::rust_kernel(rust_srv *srv, size_t num_threads) :
    _region(srv, true),
    _log(srv, NULL),
    srv(srv),
    _interrupt_kernel_loop(FALSE),
    num_threads(num_threads),
    rval(0),
    live_tasks(0),
    env(srv->env)
{
    isaac_init(this, &rctx);
    create_schedulers();
}

rust_scheduler *
rust_kernel::create_scheduler(int id) {
    _kernel_lock.lock();
    rust_message_queue *message_queue =
        new (this, "rust_message_queue") rust_message_queue(srv, this);
    rust_srv *srv = this->srv->clone();
    rust_scheduler *sched =
        new (this, "rust_scheduler")
        rust_scheduler(this, message_queue, srv, id);
    rust_handle<rust_scheduler> *handle = internal_get_sched_handle(sched);
    message_queue->associate(handle);
    message_queues.append(message_queue);
    KLOG_("created scheduler: " PTR ", id: %d, index: %d",
          sched, id, sched->list_index);
    _kernel_lock.signal_all();
    _kernel_lock.unlock();
    return sched;
}

void
rust_kernel::destroy_scheduler(rust_scheduler *sched) {
    _kernel_lock.lock();
    KLOG_("deleting scheduler: " PTR ", name: %s, index: %d",
        sched, sched->name, sched->list_index);
    sched->message_queue->disassociate();
    rust_srv *srv = sched->srv;
    delete sched;
    delete srv;
    _kernel_lock.signal_all();
    _kernel_lock.unlock();
}

void rust_kernel::create_schedulers() {
    KLOG_("Using %d scheduler threads.", num_threads);

    for(size_t i = 0; i < num_threads; ++i) {
        threads.push(create_scheduler(i));
    }
}

void rust_kernel::destroy_schedulers() {
    for(size_t i = 0; i < num_threads; ++i) {
        destroy_scheduler(threads[i]);
    }
}

rust_handle<rust_scheduler> *
rust_kernel::internal_get_sched_handle(rust_scheduler *sched) {
    rust_handle<rust_scheduler> *handle = NULL;
    if (_sched_handles.get(sched, &handle) == false) {
        handle = new (this, "rust_handle<rust_scheduler")
            rust_handle<rust_scheduler>(this, sched->message_queue, sched);
        _sched_handles.put(sched, handle);
    }
    return handle;
}

rust_handle<rust_task> *
rust_kernel::get_task_handle(rust_task *task) {
    _kernel_lock.lock();
    rust_handle<rust_task> *handle = NULL;
    if (_task_handles.get(task, &handle) == false) {
        handle =
            new (this, "rust_handle<rust_task>")
            rust_handle<rust_task>(this, task->sched->message_queue, task);
        _task_handles.put(task, handle);
    }
    _kernel_lock.unlock();
    return handle;
}

rust_handle<rust_port> *
rust_kernel::get_port_handle(rust_port *port) {
    _kernel_lock.lock();
    rust_handle<rust_port> *handle = NULL;
    if (_port_handles.get(port, &handle) == false) {
        handle = new (this, "rust_handle<rust_port>")
            rust_handle<rust_port>(this,
                                   port->task->sched->message_queue,
                                   port);
        _port_handles.put(port, handle);
    }
    _kernel_lock.unlock();
    return handle;
}

void
rust_kernel::log_all_scheduler_state() {
    for(size_t i = 0; i < num_threads; ++i) {
        threads[i]->log_state();
    }
}

/**
 * Checks for simple deadlocks.
 */
bool
rust_kernel::is_deadlocked() {
    return false;
}

void
rust_kernel::log(uint32_t level, char const *fmt, ...) {
    char buf[BUF_BYTES];
    va_list args;
    va_start(args, fmt);
    vsnprintf(buf, sizeof(buf), fmt, args);
    _log.trace_ln(NULL, level, buf);
    va_end(args);
}

void
rust_kernel::fatal(char const *fmt, ...) {
    char buf[BUF_BYTES];
    va_list args;
    va_start(args, fmt);
    vsnprintf(buf, sizeof(buf), fmt, args);
    _log.trace_ln(NULL, (uint32_t)0, buf);
    exit(1);
    va_end(args);
}

void
rust_kernel::pump_message_queues() {
    for (size_t i = 0; i < message_queues.length(); i++) {
        rust_message_queue *queue = message_queues[i];
        if (queue->is_associated() == false) {
            rust_message *message = NULL;
            while (queue->dequeue(&message)) {
                message->kernel_process();
                delete message;
            }
        }
    }
}

void
rust_kernel::start_kernel_loop() {
    _kernel_lock.lock();
    while (_interrupt_kernel_loop == false) {
        _kernel_lock.wait();
        pump_message_queues();
    }
    _kernel_lock.unlock();
}

void
rust_kernel::run() {
    KLOG_("started kernel loop");
    start_kernel_loop();
    KLOG_("finished kernel loop");
}

void
rust_kernel::terminate_kernel_loop() {
    KLOG_("terminating kernel loop");
    _interrupt_kernel_loop = true;
    signal_kernel_lock();
    join();
}

rust_kernel::~rust_kernel() {
    destroy_schedulers();

    terminate_kernel_loop();

    // It's possible that the message pump misses some messages because
    // of races, so pump any remaining messages here. By now all domain
    // threads should have been joined, so we shouldn't miss any more
    // messages.
    pump_message_queues();

    KLOG_("freeing handles");

    free_handles(_task_handles);
    KLOG_("..task handles freed");
    free_handles(_port_handles);
    KLOG_("..port handles freed");
    free_handles(_sched_handles);
    KLOG_("..sched handles freed");

    KLOG_("freeing queues");

    rust_message_queue *queue = NULL;
    while (message_queues.pop(&queue)) {
        K(srv, queue->is_empty(), "Kernel message queue should be empty "
          "before killing the kernel.");
        delete queue;
    }
}

void *
rust_kernel::malloc(size_t size, const char *tag) {
    return _region.malloc(size, tag);
}

void *
rust_kernel::realloc(void *mem, size_t size) {
    return _region.realloc(mem, size);
}

void rust_kernel::free(void *mem) {
    _region.free(mem);
}

template<class T> void
rust_kernel::free_handles(hash_map<T*, rust_handle<T>* > &map) {
    T* key;
    rust_handle<T> *value;
    while (map.pop(&key, &value)) {
        KLOG_("...freeing " PTR, value);
        delete value;
    }
}

void
rust_kernel::notify_message_enqueued(rust_message_queue *queue,
                                     rust_message *message) {
    // The message pump needs to handle this message if the queue is not
    // associated with a domain, therefore signal the message pump.
    if (queue->is_associated() == false) {
        signal_kernel_lock();
    }
}

void
rust_kernel::signal_kernel_lock() {
    _kernel_lock.lock();
    _kernel_lock.signal_all();
    _kernel_lock.unlock();
}

int rust_kernel::start_task_threads()
{
    for(size_t i = 0; i < num_threads; ++i) {
        rust_scheduler *thread = threads[i];
        thread->start();
    }

    for(size_t i = 0; i < num_threads; ++i) {
        rust_scheduler *thread = threads[i];
        thread->join();
    }

    return rval;
}

rust_task *
rust_kernel::create_task(rust_task *spawner, const char *name) {
    return threads[rand(&rctx) % num_threads]->create_task(spawner, name);
}

void rust_kernel::wakeup_schedulers() {
    for(size_t i = 0; i < num_threads; ++i) {
        threads[i]->lock.signal_all();
    }
}

#ifdef __WIN32__
void
rust_kernel::win32_require(LPCTSTR fn, BOOL ok) {
    if (!ok) {
        LPTSTR buf;
        DWORD err = GetLastError();
        FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER |
                      FORMAT_MESSAGE_FROM_SYSTEM |
                      FORMAT_MESSAGE_IGNORE_INSERTS,
                      NULL, err,
                      MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
                      (LPTSTR) &buf, 0, NULL );
        KLOG_ERR_(dom, "%s failed with error %ld: %s", fn, err, buf);
        LocalFree((HLOCAL)buf);
        I(this, ok);
    }
}
#endif

//
// Local Variables:
// mode: C++
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// compile-command: "make -k -C $RBUILD 2>&1 | sed -e 's/\\/x\\//x:\\//g'";
// End:
//