#include "moar.h"

#include "platform/time.h"

/* Initializes a new thread context. Note that this doesn't set up a

 * thread itself, it just creates the data structure that exists in

 * MoarVM per thread. */

MVMThreadContext * MVM_tc_create(MVMThreadContext *parent, MVMInstance *instance) {

    MVMThreadContext *tc = MVM_calloc(1, sizeof(MVMThreadContext));

    /* Associate with VM instance. */

    tc->instance = instance;

    /* Use default loop for main thread; create a new one for others. */

    if (instance->main_thread) {

        int r;

        tc->loop = MVM_calloc(1, sizeof(uv_loop_t));

        r = uv_loop_init(tc->loop);

        if (r < 0) {

            MVM_free(tc->loop);

            MVM_free(tc);

            MVM_exception_throw_adhoc(parent, "Could not create a new Thread: %s", uv_strerror(r));

        }

    } else {

        tc->loop = uv_default_loop();

    }

    /* Set up GC nursery. We only allocate tospace initially, and allocate

     * fromspace the first time this thread GCs, provided it ever does. */

    tc->nursery_tospace     = MVM_calloc(1, MVM_NURSERY_SIZE);

    tc->nursery_alloc       = tc->nursery_tospace;

    tc->nursery_alloc_limit = (char *)tc->nursery_alloc + MVM_NURSERY_SIZE;

    /* Set up temporary root handling. */

    tc->num_temproots   = 0;

    tc->alloc_temproots = MVM_TEMP_ROOT_BASE_ALLOC;

    tc->temproots       = MVM_malloc(sizeof(MVMCollectable **) * tc->alloc_temproots);

    /* Set up intergenerational root handling. */

    tc->num_gen2roots   = 0;

    tc->alloc_gen2roots = 64;

    tc->gen2roots       = MVM_malloc(sizeof(MVMCollectable *) * tc->alloc_gen2roots);

    /* Set up the second generation allocator. */

    tc->gen2 = MVM_gc_gen2_create(instance);

    /* Allocate an initial call stack region for the thread. */

    MVM_callstack_region_init(tc);

    /* Initialize random number generator state. */

    MVM_proc_seed(tc, (MVM_platform_now() / 10000) * MVM_proc_getpid(tc));

    /* Initialize frame sequence numbers */

    tc->next_frame_nr = 0;

    tc->current_frame_nr = 0;

    /* Initialize last_payload, so we can be sure it's never NULL and don't

     * need to check. */

    tc->last_payload = instance->VMNull;

    return tc;

}

/* Destroys a given thread context. This will also free the nursery.

 * This means that it must no longer be in use, at all; this can be

 * ensured by a GC run at thread exit that forces evacuation of all

 * objects from this nursery to the second generation. Only after

 * that is true should this be called. */

void MVM_tc_destroy(MVMThreadContext *tc) {

    /* We run once again (non-blocking) to eventually close filehandles. */

    uv_run(tc->loop, UV_RUN_NOWAIT);

    /* Free the nursery and finalization queue. */

    MVM_free(tc->nursery_fromspace);

    MVM_free(tc->nursery_tospace);

    MVM_free(tc->finalizing);

    /* Destroy the second generation allocator. */

    MVM_gc_gen2_destroy(tc->instance, tc->gen2);

    /* Destroy all callstack regions. */

    MVM_callstack_region_destroy_all(tc);

    /* Free the thread-specific storage */

    MVM_free(tc->gc_work);

    MVM_free(tc->temproots);

    MVM_free(tc->gen2roots);

    MVM_free(tc->finalize);

    /* Free any memory allocated for NFAs and multi-dim indices. */

    MVM_free(tc->nfa_done);

    MVM_free(tc->nfa_curst);

    MVM_free(tc->nfa_nextst);

    MVM_free(tc->nfa_fates);

    MVM_free(tc->nfa_longlit);

    MVM_free(tc->multi_dim_indices);

    /* Free per-thread lexotic cache. */

    MVM_free(tc->lexotic_cache);

    /* Destroy the libuv event loop */

    uv_loop_delete(tc->loop);

    /* Free the thread context itself. */

    memset(tc, 0, sizeof(MVMThreadContext));

    MVM_free(tc);

}

/* Setting and clearing mutex to release on exception throw. */

void MVM_tc_set_ex_release_mutex(MVMThreadContext *tc, uv_mutex_t *mutex) {

    if (tc->ex_release_mutex)

        MVM_exception_throw_adhoc(tc, "Internal error: multiple ex_release_mutex");

    tc->ex_release_mutex = mutex;

}

void MVM_tc_release_ex_release_mutex(MVMThreadContext *tc) {

    if (tc->ex_release_mutex)

        uv_mutex_unlock(tc->ex_release_mutex);

    tc->ex_release_mutex = NULL;

}

void MVM_tc_clear_ex_release_mutex(MVMThreadContext *tc) {

    tc->ex_release_mutex = NULL;

}