~maresja1/+junk/helenos_qemu_porting

/*
 * Copyright (c) 2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libc
 * @{
 */
/** @file
 */

#include <thread.h>
#include <libc.h>
#include <stdlib.h>
#include <libarch/faddr.h>
#include <abi/proc/uarg.h>
#include <fibril.h>
#include <stack.h>
#include <str.h>
#include <async.h>
#include <errno.h>
#include <as.h>
#include <stdio.h>
#include "private/thread.h"
#include "../include/thread.h"
#include "../include/fibril_synch.h"

#ifdef FUTEX_UPGRADABLE
#include <rcu.h>
#endif
typedef enum{
    THREAD_JOINABLE,
    THREAD_EXITED,
    THREAD_DETACHED
} thread_state_t;

typedef struct{
    uspace_arg_t arg;
    thread_id_t id;
    fibril_mutex_t state_lock;
    fibril_condvar_t state_condvar;
    thread_retval_t retval;
    thread_state_t state;
    atomic_t ref_count;
} thread_internal_t;

static futex_t threads_protect = FUTEX_INITIALIZER;
static thread_internal_t **threads = NULL;

static void thread_del(thread_internal_t *thread);

static void thread_add(thread_internal_t *thread);

static thread_internal_t *thread_get(thread_id_t id);

static thread_internal_t *thread_alloc(void);

/** Main thread function.
 *
 * This function is called from __thread_entry() and is used
 * to call the thread's implementing function and perform cleanup
 * and exit when thread returns back.
 *
 * @param uarg Pointer to userspace argument structure.
 *
 */
void __thread_main(uspace_arg_t *uarg)
{
	fibril_t *fibril = fibril_setup();
	if (fibril == NULL)
		thread_exit(0);
	
	__tcb_set(fibril->tcb);
	
#ifdef FUTEX_UPGRADABLE
	rcu_register_fibril();
	futex_upgrade_all_and_wait();
#endif
	thread_retval_t retval = uarg->uspace_thread_function(uarg->uspace_thread_arg);
	/*
	 * XXX: we cannot free the userspace stack while running on it
	 *
	 * free(uarg->uspace_stack);
	 * free(uarg);
	 */
	
	/* If there is a manager, destroy it */
	async_destroy_manager();

#ifdef FUTEX_UPGRADABLE
	rcu_deregister_fibril();
#endif
	
//	fibril_teardown(fibril);
	
	thread_exit(retval);
}

/** Create userspace thread.
 *
 * This function creates new userspace thread and allocates userspace
 * stack and userspace argument structure for it.
 *
 * @param function Function implementing the thread.
 * @param arg Argument to be passed to thread.
 * @param name Symbolic name of the thread.
 * @param tid Thread ID of the newly created thread.
 *
 * @return Zero on success or a code from @ref errno.h on failure.
 */
int thread_create(void* (*function)(void *), void *arg, const char *name,
    thread_id_t *tid)
{
    thread_internal_t *thread = thread_alloc();
	if (!thread)
		return ENOMEM;

    uspace_arg_t *uarg = &thread->arg;


    size_t stack_size = stack_size_get();
	void *stack = as_area_create(AS_AREA_ANY, stack_size,
	    AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE | AS_AREA_GUARD |
	    AS_AREA_LATE_RESERVE);
	if (stack == AS_MAP_FAILED) {
		free(uarg);
		return ENOMEM;
	}


	/* Make heap thread safe. */
	malloc_enable_multithreaded();
	
	uarg->uspace_entry = (void *) FADDR(__thread_entry);
	uarg->uspace_stack = stack;
	uarg->uspace_stack_size = stack_size;
	uarg->uspace_thread_function = function;
	uarg->uspace_thread_arg = arg;
	uarg->uspace_uarg = uarg;
	
	int rc = __SYSCALL4(SYS_THREAD_CREATE, (sysarg_t) uarg,
	    (sysarg_t) name, (sysarg_t) str_size(name), (sysarg_t) &thread->id);

    thread_add(thread);

    if (rc != EOK) {
		/*
		 * Failed to create a new thread.
		 * Free up the allocated data.
		 */
		as_area_destroy(stack);
		free(uarg);
	}

    if(tid){
        *tid = thread->id;
    }

	return rc;
}

thread_internal_t *thread_alloc(void) {
    thread_internal_t *thread = (thread_internal_t*)malloc(sizeof(thread_internal_t));
    if(thread){
        thread->state = THREAD_JOINABLE;
        atomic_set(&thread->ref_count,1);
        fibril_mutex_initialize(&thread->state_lock);
        fibril_condvar_initialize(&thread->state_condvar);
    }
    return thread;
}

void thread_add(thread_internal_t *thread)
{
    futex_down(&threads_protect);
        if(threads == NULL){
            threads = malloc(sizeof(thread_internal_t*)* THREAD_MAX);
        }
        threads[thread->id] = thread;
        fprintf(stdout, "Thread id: %"PRIu64" add to address:%p",thread->id,thread);
    futex_up(&threads_protect);
}

thread_internal_t *thread_get(thread_id_t id)
{
    thread_internal_t *ret;
    futex_down(&threads_protect);
        ret = threads[id];
    futex_up(&threads_protect);
    return ret;
}

void thread_del(thread_internal_t *thread)
{
    futex_down(&threads_protect);
        threads[thread->id] = NULL;
    fprintf(stdout, "Thread id: %"PRIu64" with address:%p deleted.",thread->id,thread);
    futex_up(&threads_protect);
}

static void thread_dealloc(thread_internal_t *thread)
{
    if(atomic_predec(&thread->ref_count)){
        return;
    }
    //TODO dealloc thread
}

/** Terminate current thread.
 *
 * @param status Exit status. Currently not used.
 *
 */
void thread_exit(thread_retval_t status)
{
    thread_id_t id = thread_get_id();
    fprintf(stdout, "Exit id:%"PRIu64"\n", id);
    thread_internal_t *thread = thread_get(id);
    fprintf(stdout, " of address:%p",thread);
    fprintf(stdout, " and id:%"PRIu64"\n", thread->id);

    fibril_mutex_lock(&thread->state_lock);
    if(thread->state == THREAD_JOINABLE){
        thread->state = THREAD_EXITED;
        thread->retval = status;
        fibril_condvar_broadcast(&thread->state_condvar);
    }
    fibril_mutex_unlock(&thread->state_lock);

//    fi
	__SYSCALL1(SYS_THREAD_EXIT, (sysarg_t) 0);

    thread_del(thread);
	/* Unreachable */
	while (1);
}


/** Detach thread.
 *
 * Currently not implemented.
 *
 * @param thread TID.
 */
int thread_detach(thread_id_t thread)
{
    return 0;
}

/** Join thread.
 *
 * Currently not implemented.
 *
 * @param thread TID.
 *
 * @return Thread exit status.
 */
int thread_join(thread_id_t thread_id, thread_retval_t *retval)
{
    fprintf(stdout, "Join to:%"PRIu64"\n", thread_id);
    int err = 0;
    thread_internal_t *thread = thread_get(thread_id);
    if(thread == NULL){
        return EINVAL;
    }


    fibril_mutex_lock(&thread->state_lock);
    fprintf(stdout, "*");
    /* Rely on pthread_cond_wait being a cancellation point to make
     pthread_join one too.  */
    while (thread->state == THREAD_JOINABLE){
        fibril_condvar_wait(&thread->state_condvar,&thread->state_lock);
        fprintf(stdout, "@");
    }


    switch (thread->state)
    {
        case THREAD_EXITED:
            /* THREAD has already exited.  Salvage its exit status.  */
            if (retval)
                *retval = thread->retval;

            fibril_mutex_unlock(&thread->state_lock);

            thread_dealloc(thread);
            break;

        default:
            /* Thou shalt not join non-joinable threads!  */
            fibril_mutex_unlock (&thread->state_lock);
            err = EINVAL;
            break;
    }

    fprintf(stderr, "Join end:%"PRIu64"\n", thread_id);
	return err;
}

/** Get current thread ID.
 *
 * @return Current thread ID.
 */
thread_id_t thread_get_id(void)
{
	thread_id_t thread_id;

	(void) __SYSCALL1(SYS_THREAD_GET_ID, (sysarg_t) &thread_id);
    fprintf(stdout, "Thread id:%"PRIu64"\n", thread_id);

	return thread_id;
}

/** @}
 */