WebSVN – HelenOS – Diff – /trunk/uspace/lib/libc/generic/async.c


/*
 * Copyright (c) 2006 Ondrej Palkovsky
 * 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
 */
 
/**
 * Asynchronous library
 *
 * The aim of this library is facilitating writing programs utilizing the
 * asynchronous nature of HelenOS IPC, yet using a normal way of programming.
 *
 * You should be able to write very simple multithreaded programs, the async
 * framework will automatically take care of most synchronization problems.
 *
 * Default semantics:
 * - async_send_*():    send asynchronously. If the kernel refuses to send
 *          more messages, [ try to get responses from kernel, if
 *          nothing found, might try synchronous ]
 *
 * Example of use (pseudo C):
 *
 * 1) Multithreaded client application
 *
 * fibril_create(fibril1, ...);
 * fibril_create(fibril2, ...);
 * ...
 *  
 * int fibril1(void *arg)
 * {
 *  conn = ipc_connect_me_to();
 *  c1 = async_send(conn);
 *  c2 = async_send(conn);
 *  async_wait_for(c1);
 *  async_wait_for(c2);
 *  ...
 * }
 *
 *
 * 2) Multithreaded server application
 * main()
 * {
 *  async_manager();
 * }
 *
 *
 * client_connection(icallid, *icall)
 * {
 *  if (want_refuse) {
 *      ipc_answer_fast(icallid, ELIMIT, 0, 0);
 *      return;
 *  }
 *  ipc_answer_fast(icallid, EOK, 0, 0);
 *
 *  callid = async_get_call(&call);
 *  handle_call(callid, call);
 *  ipc_answer_fast(callid, 1, 2, 3);
 *
 *  callid = async_get_call(&call);
 *  ....
 * }
 *
 */
 
#include <futex.h>
#include <async.h>
#include <fibril.h>
#include <stdio.h>
#include <libadt/hash_table.h>
#include <libadt/list.h>
#include <ipc/ipc.h>
#include <assert.h>
#include <errno.h>
#include <time.h>
#include <arch/barrier.h>
 
atomic_t async_futex = FUTEX_INITIALIZER;
static hash_table_t conn_hash_table;
static LIST_INITIALIZE(timeout_list);
 
typedef struct {
    /** Expiration time for waiting fibril. */
    struct timeval expires;    
    /** If true, this struct is in the timeout list. */
    int inlist;
    link_t link;
 
    /** Fibril waiting for this message. */
    fid_t fid;
    /** If this fibril is currently active. */
    int active;
    /** If true, we timed out. */
    int timedout;
} awaiter_t;
 
typedef struct {
    awaiter_t wdata;
 
    int done;                   /**< If reply was received */
    ipc_call_t *dataptr;        /**< Pointer where the answer data
                     *   is stored */
    ipcarg_t retval;
} amsg_t;
 
typedef struct {
    link_t link;
    ipc_callid_t callid;
    ipc_call_t call;
} msg_t;
 
typedef struct {
    awaiter_t wdata;
 
    link_t link;            /**< Hash table link. */
    ipcarg_t in_phone_hash;     /**< Incoming phone hash. */
    link_t msg_queue;       /**< Messages that should be delivered
                     *   to this fibril. */
    /* Structures for connection opening packet */
    ipc_callid_t callid;
    ipc_call_t call;
    ipc_callid_t close_callid;  /* Identification of closing packet. */
    void (*cfibril)(ipc_callid_t, ipc_call_t *);
} connection_t;
 
/** Identifier of the incoming connection handled by the current fibril. */
__thread connection_t *FIBRIL_connection;
/** If true, it is forbidden to use async_req functions and
 *  all preemption is disabled */
__thread int in_interrupt_handler;
 
static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);
static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);
static async_client_conn_t client_connection = default_client_connection;
static async_client_conn_t interrupt_received = default_interrupt_received;
 
/** Add microseconds to give timeval */
static void tv_add(struct timeval *tv, suseconds_t usecs)
{
    tv->tv_sec += usecs / 1000000;
    tv->tv_usec += usecs % 1000000;
    if (tv->tv_usec > 1000000) {
        tv->tv_sec++;
        tv->tv_usec -= 1000000;
    }
}
 
/** Subtract 2 timevals, return microseconds difference */
static suseconds_t tv_sub(struct timeval *tv1, struct timeval *tv2)
{
    suseconds_t result;
 
    result = tv1->tv_usec - tv2->tv_usec;
    result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
 
    return result;
}
 
/** Compare timeval
 *
 * @return 1 if tv1 > tv2, otherwise 0
 */
static int tv_gt(struct timeval *tv1, struct timeval *tv2)
{
    if (tv1->tv_sec > tv2->tv_sec)
        return 1;
    if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
        return 1;
    return 0;
}
static int tv_gteq(struct timeval *tv1, struct timeval *tv2)
{
    if (tv1->tv_sec > tv2->tv_sec)
        return 1;
    if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
        return 1;
    return 0;
}
 
/* Hash table functions */
#define CONN_HASH_TABLE_CHAINS  32
 
static hash_index_t conn_hash(unsigned long *key)
{
    assert(key);
    return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;
}
 
static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)
{
    connection_t *hs;
 
    hs = hash_table_get_instance(item, connection_t, link);
   
    return key[0] == hs->in_phone_hash;
}
 
static void conn_remove(link_t *item)
{
    free(hash_table_get_instance(item, connection_t, link));
}
 
 
/** Operations for NS hash table. */
static hash_table_operations_t conn_hash_table_ops = {
    .hash = conn_hash,
    .compare = conn_compare,
    .remove_callback = conn_remove
};
 
/** Insert sort timeout msg into timeouts list
 *
 */
static void insert_timeout(awaiter_t *wd)
{
    link_t *tmp;
    awaiter_t *cur;
 
    wd->timedout = 0;
    wd->inlist = 1;
 
    tmp = timeout_list.next;
    while (tmp != &timeout_list) {
        cur = list_get_instance(tmp, awaiter_t, link);
        if (tv_gteq(&cur->expires, &wd->expires))
            break;
        tmp = tmp->next;
    }
    list_append(&wd->link, tmp);
}
 
 
 
/** Try to route a call to an appropriate connection fibril
 *
 */
static int route_call(ipc_callid_t callid, ipc_call_t *call)
{
    connection_t *conn;
    msg_t *msg;
    link_t *hlp;
    unsigned long key;
 
    futex_down(&async_futex);
 
    key = call->in_phone_hash;
    hlp = hash_table_find(&conn_hash_table, &key);
    if (!hlp) {
        futex_up(&async_futex);
        return 0;
    }
    conn = hash_table_get_instance(hlp, connection_t, link);
 
    msg = malloc(sizeof(*msg));
    msg->callid = callid;
    msg->call = *call;
    list_append(&msg->link, &conn->msg_queue);
 
    if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)
        conn->close_callid = callid;
   
    /* If the call is waiting for event, run it */
    if (!conn->wdata.active) {
        /* If in timeout list, remove it */
        if (conn->wdata.inlist) {
            conn->wdata.inlist = 0;
            list_remove(&conn->wdata.link);
        }
        conn->wdata.active = 1;
        fibril_add_ready(conn->wdata.fid);
    }
 
    futex_up(&async_futex);
 
    return 1;
}
 
/** Return new incoming message for the current (fibril-local) connection */
ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)
{
    msg_t *msg;
    ipc_callid_t callid;
    connection_t *conn;
   
    assert(FIBRIL_connection);
    /* GCC 4.1.0 coughs on FIBRIL_connection-> dereference,
     * GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.
     *           I would never expect to find so many errors in
     *           compiler *($&$(*&$
     */
    conn = FIBRIL_connection;
 
    futex_down(&async_futex);
 
    if (usecs) {
        gettimeofday(&conn->wdata.expires, NULL);
        tv_add(&conn->wdata.expires, usecs);
    } else {
        conn->wdata.inlist = 0;
    }
    /* If nothing in queue, wait until something appears */
    while (list_empty(&conn->msg_queue)) {
        if (usecs)
            insert_timeout(&conn->wdata);
 
        conn->wdata.active = 0;
        fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
        /* Futex is up after getting back from async_manager
         * get it again */
        futex_down(&async_futex);
        if (usecs && conn->wdata.timedout &&
            list_empty(&conn->msg_queue)) {
            /* If we timed out-> exit */
            futex_up(&async_futex);
            return 0;
        }
    }
   
    msg = list_get_instance(conn->msg_queue.next, msg_t, link);
    list_remove(&msg->link);
    callid = msg->callid;
    *call = msg->call;
    free(msg);
   
    futex_up(&async_futex);
    return callid;
}
 
/** Fibril function that gets created on new connection
 *
 * This function is defined as a weak symbol - to be redefined in
 * user code.
 */
static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
{
    ipc_answer_fast(callid, ENOENT, 0, 0);
}
static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
{
}
 
/** Wrapper for client connection fibril.
 *
 * When new connection arrives, a fibril with this implementing function is
 * created. It calls client_connection() and does the final cleanup.
 *
 
 * @param arg       Connection structure pointer
 *
 * @return      Always zero.
 */
static int connection_fibril(void  *arg)
{
    unsigned long key;
    msg_t *msg;
    int close_answered = 0;
 
    /* Setup fibril-local connection pointer */
    FIBRIL_connection = (connection_t *) arg;
    FIBRIL_connection->cfibril(FIBRIL_connection->callid,
        &FIBRIL_connection->call);
   
    /* Remove myself from connection hash table */
    futex_down(&async_futex);
    key = FIBRIL_connection->in_phone_hash;
    hash_table_remove(&conn_hash_table, &key, 1);
    futex_up(&async_futex);
   
    /* Answer all remaining messages with ehangup */
    while (!list_empty(&FIBRIL_connection->msg_queue)) {
        msg = list_get_instance(FIBRIL_connection->msg_queue.next,
            msg_t, link);
        list_remove(&msg->link);
        if (msg->callid == FIBRIL_connection->close_callid)
            close_answered = 1;
        ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
        free(msg);
    }
    if (FIBRIL_connection->close_callid)
        ipc_answer_fast(FIBRIL_connection->close_callid, 0, 0, 0);
   
    return 0;
}
 
/** Create a new fibril for a new connection.
 *
 * Creates new fibril for connection, fills in connection structures and inserts
 
 * it into the hash table, so that later we can easily do routing of messages to
 * particular fibrils.
 *
 * @param in_phone_hash Identification of the incoming connection
 * @param callid    Callid of the IPC_M_CONNECT_ME_TO packet
 * @param call      Call data of the opening packet
 * @param cfibril   Fibril function that should be called upon
 *                  opening the connection
 * @return      New fibril id.
 */
fid_t async_new_connection(ipcarg_t in_phone_hash, ipc_callid_t callid,
    ipc_call_t *call, void (*cfibril)(ipc_callid_t, ipc_call_t *))
{
    connection_t *conn;
    unsigned long key;
 
    conn = malloc(sizeof(*conn));
    if (!conn) {
        ipc_answer_fast(callid, ENOMEM, 0, 0);
        return NULL;
    }
    conn->in_phone_hash = in_phone_hash;
    list_initialize(&conn->msg_queue);
    conn->callid = callid;
    conn->close_callid = 0;
    if (call)
        conn->call = *call;
    conn->wdata.active = 1; /* We will activate it asap */
    conn->cfibril = cfibril;
 
    conn->wdata.fid = fibril_create(connection_fibril, conn);
    if (!conn->wdata.fid) {
        free(conn);
        ipc_answer_fast(callid, ENOMEM, 0, 0);
        return NULL;
    }
    /* Add connection to hash table */
    key = conn->in_phone_hash;
    futex_down(&async_futex);
    hash_table_insert(&conn_hash_table, &key, &conn->link);
    futex_up(&async_futex);
 
    fibril_add_ready(conn->wdata.fid);
 
    return conn->wdata.fid;
}
 
/** Handle a call that was received. */
static void handle_call(ipc_callid_t callid, ipc_call_t *call)
{
    /* Unrouted call - do some default behaviour */
    if ((callid & IPC_CALLID_NOTIFICATION)) {
        in_interrupt_handler = 1;
        (*interrupt_received)(callid,call);
        in_interrupt_handler = 0;
        return;
    }      
 
    switch (IPC_GET_METHOD(*call)) {
    case IPC_M_CONNECT_ME_TO:
        /* Open new connection with fibril etc. */
        async_new_connection(IPC_GET_ARG3(*call), callid, call,
            client_connection);
        return;
    }
 
    /* Try to route call through connection tables */
    if (route_call(callid, call))
        return;
 
    /* Unknown call from unknown phone - hang it up */
    ipc_answer_fast(callid, EHANGUP, 0, 0);
}
 
/** Fire all timeouts that expired. */
 
 
static void handle_expired_timeouts(void)
{
    struct timeval tv;
    awaiter_t *waiter;
    link_t *cur;
 
    gettimeofday(&tv,NULL);
    futex_down(&async_futex);
 
    cur = timeout_list.next;
    while (cur != &timeout_list) {
        waiter = list_get_instance(cur, awaiter_t, link);
        if (tv_gt(&waiter->expires, &tv))
            break;
        cur = cur->next;
        list_remove(&waiter->link);
        waiter->inlist = 0;
        waiter->timedout = 1;
        /* Redundant condition? The fibril should not
         * be active when it gets here.
         */
        if (!waiter->active) {
            waiter->active = 1;
            fibril_add_ready(waiter->fid);
        }
    }
 
    futex_up(&async_futex);
}
 
/** Endless loop dispatching incoming calls and answers */
static int async_manager_worker(void)
{
    ipc_call_t call;
    ipc_callid_t callid;
    int timeout;
    awaiter_t *waiter;
    struct timeval tv;
 
    while (1) {
        if (fibril_schedule_next_adv(FIBRIL_FROM_MANAGER)) {
            futex_up(&async_futex);
            /* async_futex is always held
             * when entering manager fibril
             */
            continue;
        }
        futex_down(&async_futex);
        if (!list_empty(&timeout_list)) {
            waiter = list_get_instance(timeout_list.next, awaiter_t,
                link);
            gettimeofday(&tv, NULL);
            if (tv_gteq(&tv, &waiter->expires)) {
                futex_up(&async_futex);
                handle_expired_timeouts();
                continue;
            } else
                timeout = tv_sub(&waiter->expires, &tv);
        } else
            timeout = SYNCH_NO_TIMEOUT;
        futex_up(&async_futex);
 
        callid = ipc_wait_cycle(&call, timeout, SYNCH_FLAGS_NONE);
 
        if (!callid) {
            handle_expired_timeouts();
            continue;
        }
 
        if (callid & IPC_CALLID_ANSWERED) {
            continue;
        }
 
        handle_call(callid, &call);
    }
   
    return 0;
}
 
/** Function to start async_manager as a standalone fibril.
 *
 * When more kernel threads are used, one async manager should
 
 
 * exist per thread.
 */
static int async_manager_fibril(void *arg)
{
    futex_up(&async_futex);
    /* async_futex is always locked when entering
     * manager */
    async_manager_worker();
   
    return 0;
}
 
/** Add one manager to manager list */
void async_create_manager(void)
{
    fid_t fid;
 
    fid = fibril_create(async_manager_fibril, NULL);
    fibril_add_manager(fid);
}
 
/** Remove one manager from manager list */
void async_destroy_manager(void)
{
    fibril_remove_manager();
}
 
/** Initialize internal structures needed for async manager */
int _async_init(void)
{
    if (!hash_table_create(&conn_hash_table, CONN_HASH_TABLE_CHAINS, 1,
        &conn_hash_table_ops)) {
        printf("%s: cannot create hash table\n", "async");
        return ENOMEM;
    }
   
    return 0;
}
 
/** IPC handler for messages in async framework
 *
 * Notify the fibril which is waiting for this message, that it arrived
 */
static void reply_received(void *private, int retval, ipc_call_t *data)
 
{
    amsg_t *msg = (amsg_t *) private;
 
    msg->retval = retval;
 
    futex_down(&async_futex);
    /* Copy data after futex_down, just in case the
     * call was detached
     */
    if (msg->dataptr)
        *msg->dataptr = *data;
 
    write_barrier();
    /* Remove message from timeout list */
    if (msg->wdata.inlist)
        list_remove(&msg->wdata.link);
    msg->done = 1;
    if (! msg->wdata.active) {
        msg->wdata.active = 1;
        fibril_add_ready(msg->wdata.fid);
    }
    futex_up(&async_futex);
}
 
/** Send message and return id of the sent message
 *
 * The return value can be used as input for async_wait() to wait
 * for completion.
 */
aid_t async_send_2(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
    ipc_call_t *dataptr)
{
    amsg_t *msg;
 
    if (in_interrupt_handler) {
        printf("Cannot send asynchronous request in interrupt "
            "handler.\n");
        _exit(1);
    }
 
    msg = malloc(sizeof(*msg));
    msg->done = 0;
    msg->dataptr = dataptr;
 
    msg->wdata.active = 1; /* We may sleep in next method, but it
                * will use it's own mechanism */
    ipc_call_async_2(phoneid, method, arg1, arg2, msg, reply_received, 1);
 
    return (aid_t) msg;
}
 
/** Send message and return id of the sent message
 *
 * The return value can be used as input for async_wait() to wait
 * for completion.
 */
aid_t async_send_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
    ipcarg_t arg3, ipc_call_t *dataptr)
{
    amsg_t *msg;
 
    if (in_interrupt_handler) {
        printf("Cannot send asynchronous request in interrupt handler.\n");
        _exit(1);
    }
 
    msg = malloc(sizeof(*msg));
    msg->done = 0;
    msg->dataptr = dataptr;
 
    msg->wdata.active = 1; /* We may sleep in next method, but it
                * will use it's own mechanism */
    ipc_call_async_3(phoneid, method, arg1, arg2, arg3, msg, reply_received,
        1);
 
    return (aid_t) msg;
}
 
/** Wait for a message sent by async framework
 *
 * @param amsgid    Message ID to wait for
 * @param retval    Pointer to variable where will be stored retval of the
 *          answered message. If NULL, it is ignored.
 
 */
void async_wait_for(aid_t amsgid, ipcarg_t *retval)
{
    amsg_t *msg = (amsg_t *) amsgid;
 
    futex_down(&async_futex);
    if (msg->done) {
        futex_up(&async_futex);
        goto done;
    }
 
    msg->wdata.fid = fibril_get_id();
    msg->wdata.active = 0;
    msg->wdata.inlist = 0;
    /* Leave locked async_futex when entering this function */
    fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
    /* futex is up automatically after fibril_schedule_next...*/
done:
    if (retval)
        *retval = msg->retval;
    free(msg);
}
 
/** Wait for a message sent by async framework with timeout
 *
 * @param amsgid Message ID to wait for
 * @param retval Pointer to variable where will be stored retval
 *               of the answered message. If NULL, it is ignored.
 * @param timeout Timeout in usecs
 * @return 0 on success, ETIMEOUT if timeout expired
 *
 */
int async_wait_timeout(aid_t amsgid, ipcarg_t *retval, suseconds_t timeout)
{
    amsg_t *msg = (amsg_t *) amsgid;
 
    /* TODO: Let it go through the event read at least once */
    if (timeout < 0)
        return ETIMEOUT;
 
    futex_down(&async_futex);
    if (msg->done) {
        futex_up(&async_futex);
        goto done;
    }
 
    gettimeofday(&msg->wdata.expires, NULL);
    tv_add(&msg->wdata.expires, timeout);
 
    msg->wdata.fid = fibril_get_id();
    msg->wdata.active = 0;
    insert_timeout(&msg->wdata);
 
    /* Leave locked async_futex when entering this function */
    fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
    /* futex is up automatically after fibril_schedule_next...*/
 
    if (!msg->done)
        return ETIMEOUT;
 
done:
    if (retval)
        *retval = msg->retval;
    free(msg);
 
    return 0;
}
 
/** Wait specified time, but in the meantime handle incoming events
 *
 * @param timeout Time in microseconds to wait
 */
void async_usleep(suseconds_t timeout)
{
    amsg_t *msg;
   
    if (in_interrupt_handler) {
        printf("Cannot call async_usleep in interrupt handler.\n");
        _exit(1);
    }
 
    msg = malloc(sizeof(*msg));
    if (!msg)
        return;
 
    msg->wdata.fid = fibril_get_id();
    msg->wdata.active = 0;
 
    gettimeofday(&msg->wdata.expires, NULL);
    tv_add(&msg->wdata.expires, timeout);
 
    futex_down(&async_futex);
    insert_timeout(&msg->wdata);
    /* Leave locked the async_futex when entering this function */
    fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
    /* futex is up automatically after fibril_schedule_next_adv()...*/
    free(msg);
}
 
/** Set function that is called when IPC_M_CONNECT_ME_TO is received.
 *
 * @param conn Function that will form a new fibril.
 */
void async_set_client_connection(async_client_conn_t conn)
{
    client_connection = conn;
}
void async_set_interrupt_received(async_client_conn_t conn)
{
    interrupt_received = conn;
}
 
/* Primitive functions for simple communication */
void async_msg_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
         ipcarg_t arg2, ipcarg_t arg3)
{
    ipc_call_async_3(phoneid, method, arg1, arg2, arg3, NULL, NULL,
        !in_interrupt_handler);
}
 
void async_msg_2(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2)
{
    ipc_call_async_2(phoneid, method, arg1, arg2, NULL, NULL,
        !in_interrupt_handler);
}
 
/** @}
 */
 

Rev 2484	Rev 2485
1	/*	1	/*
2	* Copyright (c) 2006 Ondrej Palkovsky	2	* Copyright (c) 2006 Ondrej Palkovsky
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup libc	29	/** @addtogroup libc
30	* @{	30	* @{
31	*/	31	*/
32	/** @file	32	/** @file
33	*/	33	*/
34		34
35	/**	35	/**
36	* Asynchronous library	36	* Asynchronous library
37	*	37	*
38	* The aim of this library is facilitating writing programs utilizing the	38	* The aim of this library is facilitating writing programs utilizing the
39	* asynchronous nature of HelenOS IPC, yet using a normal way of programming.	39	* asynchronous nature of HelenOS IPC, yet using a normal way of programming.
40	*	40	*
41	* You should be able to write very simple multithreaded programs, the async	41	* You should be able to write very simple multithreaded programs, the async
42	* framework will automatically take care of most synchronization problems.	42	* framework will automatically take care of most synchronization problems.
43	*	43	*
44	* Default semantics:	44	* Default semantics:
45	* - async_send_*(): send asynchronously. If the kernel refuses to send	45	* - async_send_*(): send asynchronously. If the kernel refuses to send
46	* more messages, [ try to get responses from kernel, if	46	* more messages, [ try to get responses from kernel, if
47	* nothing found, might try synchronous ]	47	* nothing found, might try synchronous ]
48	*	48	*
49	* Example of use (pseudo C):	49	* Example of use (pseudo C):
50	*	50	*
51	* 1) Multithreaded client application	51	* 1) Multithreaded client application
52	*	52	*
53	* fibril_create(fibril1, ...);	53	* fibril_create(fibril1, ...);
54	* fibril_create(fibril2, ...);	54	* fibril_create(fibril2, ...);
55	* ...	55	* ...
56	*	56	*
57	* int fibril1(void *arg)	57	* int fibril1(void *arg)
58	* {	58	* {
59	* conn = ipc_connect_me_to();	59	* conn = ipc_connect_me_to();
60	* c1 = async_send(conn);	60	* c1 = async_send(conn);
61	* c2 = async_send(conn);	61	* c2 = async_send(conn);
62	* async_wait_for(c1);	62	* async_wait_for(c1);
63	* async_wait_for(c2);	63	* async_wait_for(c2);
64	* ...	64	* ...
65	* }	65	* }
66	*	66	*
67	*	67	*
68	* 2) Multithreaded server application	68	* 2) Multithreaded server application
69	* main()	69	* main()
70	* {	70	* {
71	* async_manager();	71	* async_manager();
72	* }	72	* }
73	*	73	*
74	*	74	*
75	* client_connection(icallid, *icall)	75	* client_connection(icallid, *icall)
76	* {	76	* {
77	* if (want_refuse) {	77	* if (want_refuse) {
78	* ipc_answer_fast(icallid, ELIMIT, 0, 0);	78	* ipc_answer_fast(icallid, ELIMIT, 0, 0);
79	* return;	79	* return;
80	* }	80	* }
81	* ipc_answer_fast(icallid, EOK, 0, 0);	81	* ipc_answer_fast(icallid, EOK, 0, 0);
82	*	82	*
83	* callid = async_get_call(&call);	83	* callid = async_get_call(&call);
84	* handle_call(callid, call);	84	* handle_call(callid, call);
85	* ipc_answer_fast(callid, 1, 2, 3);	85	* ipc_answer_fast(callid, 1, 2, 3);
86	*	86	*
87	* callid = async_get_call(&call);	87	* callid = async_get_call(&call);
88	* ....	88	* ....
89	* }	89	* }
90	*	90	*
91	*/	91	*/
92		92
93	#include <futex.h>	93	#include <futex.h>
94	#include <async.h>	94	#include <async.h>
95	#include <fibril.h>	95	#include <fibril.h>
96	#include <stdio.h>	96	#include <stdio.h>
97	#include <libadt/hash_table.h>	97	#include <libadt/hash_table.h>
98	#include <libadt/list.h>	98	#include <libadt/list.h>
99	#include <ipc/ipc.h>	99	#include <ipc/ipc.h>
100	#include <assert.h>	100	#include <assert.h>
101	#include <errno.h>	101	#include <errno.h>
102	#include <time.h>	102	#include <time.h>
103	#include <arch/barrier.h>	103	#include <arch/barrier.h>
104		104
105	atomic_t async_futex = FUTEX_INITIALIZER;	105	atomic_t async_futex = FUTEX_INITIALIZER;
106	static hash_table_t conn_hash_table;	106	static hash_table_t conn_hash_table;
107	static LIST_INITIALIZE(timeout_list);	107	static LIST_INITIALIZE(timeout_list);
108		108
109	typedef struct {	109	typedef struct {
110	/** Expiration time for waiting fibril. */	110	/** Expiration time for waiting fibril. */
111	struct timeval expires;	111	struct timeval expires;
112	/** If true, this struct is in the timeout list. */	112	/** If true, this struct is in the timeout list. */
113	int inlist;	113	int inlist;
114	link_t link;	114	link_t link;
115		115
116	/** Fibril waiting for this message. */	116	/** Fibril waiting for this message. */
117	fid_t fid;	117	fid_t fid;
118	/** If this fibril is currently active. */	118	/** If this fibril is currently active. */
119	int active;	119	int active;
120	/** If true, we timed out. */	120	/** If true, we timed out. */
121	int timedout;	121	int timedout;
122	} awaiter_t;	122	} awaiter_t;
123		123
124	typedef struct {	124	typedef struct {
125	awaiter_t wdata;	125	awaiter_t wdata;
126		126
127	int done; /*< If reply was received /	127	int done; /*< If reply was received /
128	ipc_call_t dataptr; /*< Pointer where the answer data	128	ipc_call_t dataptr; /*< Pointer where the answer data
129	* is stored */	129	* is stored */
130	ipcarg_t retval;	130	ipcarg_t retval;
131	} amsg_t;	131	} amsg_t;
132		132
133	typedef struct {	133	typedef struct {
134	link_t link;	134	link_t link;
135	ipc_callid_t callid;	135	ipc_callid_t callid;
136	ipc_call_t call;	136	ipc_call_t call;
137	} msg_t;	137	} msg_t;
138		138
139	typedef struct {	139	typedef struct {
140	awaiter_t wdata;	140	awaiter_t wdata;
141		141
142	link_t link; /*< Hash table link. /	142	link_t link; /*< Hash table link. /
143	ipcarg_t in_phone_hash; /*< Incoming phone hash. /	143	ipcarg_t in_phone_hash; /*< Incoming phone hash. /
144	link_t msg_queue; /**< Messages that should be delivered	144	link_t msg_queue; /**< Messages that should be delivered
145	* to this fibril. */	145	* to this fibril. */
146	/* Structures for connection opening packet */	146	/* Structures for connection opening packet */
147	ipc_callid_t callid;	147	ipc_callid_t callid;
148	ipc_call_t call;	148	ipc_call_t call;
149	ipc_callid_t close_callid; /* Identification of closing packet. */	149	ipc_callid_t close_callid; /* Identification of closing packet. */
150	void (cfibril)(ipc_callid_t, ipc_call_t );	150	void (cfibril)(ipc_callid_t, ipc_call_t );
151	} connection_t;	151	} connection_t;
152		152
153	/** Identifier of the incoming connection handled by the current fibril. */	153	/** Identifier of the incoming connection handled by the current fibril. */
154	__thread connection_t *FIBRIL_connection;	154	__thread connection_t *FIBRIL_connection;
155	/** If true, it is forbidden to use async_req functions and	155	/** If true, it is forbidden to use async_req functions and
156	* all preemption is disabled */	156	* all preemption is disabled */
157	__thread int in_interrupt_handler;	157	__thread int in_interrupt_handler;
158		158
159	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);	159	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);
160	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);	160	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);
161	static async_client_conn_t client_connection = default_client_connection;	161	static async_client_conn_t client_connection = default_client_connection;
162	static async_client_conn_t interrupt_received = default_interrupt_received;	162	static async_client_conn_t interrupt_received = default_interrupt_received;
163		163
164	/** Add microseconds to give timeval */	164	/** Add microseconds to give timeval */
165	static void tv_add(struct timeval *tv, suseconds_t usecs)	165	static void tv_add(struct timeval *tv, suseconds_t usecs)
166	{	166	{
167	tv->tv_sec += usecs / 1000000;	167	tv->tv_sec += usecs / 1000000;
168	tv->tv_usec += usecs % 1000000;	168	tv->tv_usec += usecs % 1000000;
169	if (tv->tv_usec > 1000000) {	169	if (tv->tv_usec > 1000000) {
170	tv->tv_sec++;	170	tv->tv_sec++;
171	tv->tv_usec -= 1000000;	171	tv->tv_usec -= 1000000;
172	}	172	}
173	}	173	}
174		174
175	/** Subtract 2 timevals, return microseconds difference */	175	/** Subtract 2 timevals, return microseconds difference */
176	static suseconds_t tv_sub(struct timeval tv1, struct timeval tv2)	176	static suseconds_t tv_sub(struct timeval tv1, struct timeval tv2)
177	{	177	{
178	suseconds_t result;	178	suseconds_t result;
179		179
180	result = tv1->tv_usec - tv2->tv_usec;	180	result = tv1->tv_usec - tv2->tv_usec;
181	result += (tv1->tv_sec - tv2->tv_sec) * 1000000;	181	result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
182		182
183	return result;	183	return result;
184	}	184	}
185		185
186	/** Compare timeval	186	/** Compare timeval
187	*	187	*
188	* @return 1 if tv1 > tv2, otherwise 0	188	* @return 1 if tv1 > tv2, otherwise 0
189	*/	189	*/
190	static int tv_gt(struct timeval tv1, struct timeval tv2)	190	static int tv_gt(struct timeval tv1, struct timeval tv2)
191	{	191	{
192	if (tv1->tv_sec > tv2->tv_sec)	192	if (tv1->tv_sec > tv2->tv_sec)
193	return 1;	193	return 1;
194	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)	194	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
195	return 1;	195	return 1;
196	return 0;	196	return 0;
197	}	197	}
198	static int tv_gteq(struct timeval tv1, struct timeval tv2)	198	static int tv_gteq(struct timeval tv1, struct timeval tv2)
199	{	199	{
200	if (tv1->tv_sec > tv2->tv_sec)	200	if (tv1->tv_sec > tv2->tv_sec)
201	return 1;	201	return 1;
202	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)	202	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
203	return 1;	203	return 1;
204	return 0;	204	return 0;
205	}	205	}
206		206
207	/* Hash table functions */	207	/* Hash table functions */
208	#define CONN_HASH_TABLE_CHAINS 32	208	#define CONN_HASH_TABLE_CHAINS 32
209		209
210	static hash_index_t conn_hash(unsigned long *key)	210	static hash_index_t conn_hash(unsigned long *key)
211	{	211	{
212	assert(key);	212	assert(key);
213	return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;	213	return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;
214	}	214	}
215		215
216	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)	216	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)
217	{	217	{
218	connection_t *hs;	218	connection_t *hs;
219		219
220	hs = hash_table_get_instance(item, connection_t, link);	220	hs = hash_table_get_instance(item, connection_t, link);
221		221
222	return key[0] == hs->in_phone_hash;	222	return key[0] == hs->in_phone_hash;
223	}	223	}
224		224
225	static void conn_remove(link_t *item)	225	static void conn_remove(link_t *item)
226	{	226	{
227	free(hash_table_get_instance(item, connection_t, link));	227	free(hash_table_get_instance(item, connection_t, link));
228	}	228	}
229		229
230		230
231	/** Operations for NS hash table. */	231	/** Operations for NS hash table. */
232	static hash_table_operations_t conn_hash_table_ops = {	232	static hash_table_operations_t conn_hash_table_ops = {
233	.hash = conn_hash,	233	.hash = conn_hash,
234	.compare = conn_compare,	234	.compare = conn_compare,
235	.remove_callback = conn_remove	235	.remove_callback = conn_remove
236	};	236	};
237		237
238	/** Insert sort timeout msg into timeouts list	238	/** Insert sort timeout msg into timeouts list
239	*	239	*
240	*/	240	*/
241	static void insert_timeout(awaiter_t *wd)	241	static void insert_timeout(awaiter_t *wd)
242	{	242	{
243	link_t *tmp;	243	link_t *tmp;
244	awaiter_t *cur;	244	awaiter_t *cur;
245		245
246	wd->timedout = 0;	246	wd->timedout = 0;
247	wd->inlist = 1;	247	wd->inlist = 1;
248		248
249	tmp = timeout_list.next;	249	tmp = timeout_list.next;
250	while (tmp != &timeout_list) {	250	while (tmp != &timeout_list) {
251	cur = list_get_instance(tmp, awaiter_t, link);	251	cur = list_get_instance(tmp, awaiter_t, link);
252	if (tv_gteq(&cur->expires, &wd->expires))	252	if (tv_gteq(&cur->expires, &wd->expires))
253	break;	253	break;
254	tmp = tmp->next;	254	tmp = tmp->next;
255	}	255	}
256	list_append(&wd->link, tmp);	256	list_append(&wd->link, tmp);
257	}	257	}
258		258
259	/*************************************************/	-
260		-
261	/** Try to route a call to an appropriate connection thread	259	/** Try to route a call to an appropriate connection fibril
262	*	260	*
263	*/	261	*/
264	static int route_call(ipc_callid_t callid, ipc_call_t *call)	262	static int route_call(ipc_callid_t callid, ipc_call_t *call)
265	{	263	{
266	connection_t *conn;	264	connection_t *conn;
267	msg_t *msg;	265	msg_t *msg;
268	link_t *hlp;	266	link_t *hlp;
269	unsigned long key;	267	unsigned long key;
270		268
271	futex_down(&async_futex);	269	futex_down(&async_futex);
272		270
273	key = call->in_phone_hash;	271	key = call->in_phone_hash;
274	hlp = hash_table_find(&conn_hash_table, &key);	272	hlp = hash_table_find(&conn_hash_table, &key);
275	if (!hlp) {	273	if (!hlp) {
276	futex_up(&async_futex);	274	futex_up(&async_futex);
277	return 0;	275	return 0;
278	}	276	}
279	conn = hash_table_get_instance(hlp, connection_t, link);	277	conn = hash_table_get_instance(hlp, connection_t, link);
280		278
281	msg = malloc(sizeof(*msg));	279	msg = malloc(sizeof(*msg));
282	msg->callid = callid;	280	msg->callid = callid;
283	msg->call = *call;	281	msg->call = *call;
284	list_append(&msg->link, &conn->msg_queue);	282	list_append(&msg->link, &conn->msg_queue);
285		283
286	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)	284	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)
287	conn->close_callid = callid;	285	conn->close_callid = callid;
288		286
289	/* If the call is waiting for event, run it */	287	/* If the call is waiting for event, run it */
290	if (!conn->wdata.active) {	288	if (!conn->wdata.active) {
291	/* If in timeout list, remove it */	289	/* If in timeout list, remove it */
292	if (conn->wdata.inlist) {	290	if (conn->wdata.inlist) {
293	conn->wdata.inlist = 0;	291	conn->wdata.inlist = 0;
294	list_remove(&conn->wdata.link);	292	list_remove(&conn->wdata.link);
295	}	293	}
296	conn->wdata.active = 1;	294	conn->wdata.active = 1;
297	fibril_add_ready(conn->wdata.fid);	295	fibril_add_ready(conn->wdata.fid);
298	}	296	}
299		297
300	futex_up(&async_futex);	298	futex_up(&async_futex);
301		299
302	return 1;	300	return 1;
303	}	301	}
304		302
305	/** Return new incoming message for current(thread-local) connection */	303	/** Return new incoming message for the current (fibril-local) connection */
306	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)	304	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)
307	{	305	{
308	msg_t *msg;	306	msg_t *msg;
309	ipc_callid_t callid;	307	ipc_callid_t callid;
310	connection_t *conn;	308	connection_t *conn;
311		309
312	assert(FIBRIL_connection);	310	assert(FIBRIL_connection);
313	/* GCC 4.1.0 coughs on FIBRIL_connection-> dereference,	311	/* GCC 4.1.0 coughs on FIBRIL_connection-> dereference,
314	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.	312	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.
315	* I would never expect to find so many errors in	313	* I would never expect to find so many errors in
316	* compiler ($&$(&$	314	* compiler ($&$(&$
317	*/	315	*/
318	conn = FIBRIL_connection;	316	conn = FIBRIL_connection;
319		317
320	futex_down(&async_futex);	318	futex_down(&async_futex);
321		319
322	if (usecs) {	320	if (usecs) {
323	gettimeofday(&conn->wdata.expires, NULL);	321	gettimeofday(&conn->wdata.expires, NULL);
324	tv_add(&conn->wdata.expires, usecs);	322	tv_add(&conn->wdata.expires, usecs);
325	} else {	323	} else {
326	conn->wdata.inlist = 0;	324	conn->wdata.inlist = 0;
327	}	325	}
328	/* If nothing in queue, wait until something appears */	326	/* If nothing in queue, wait until something appears */
329	while (list_empty(&conn->msg_queue)) {	327	while (list_empty(&conn->msg_queue)) {
330	if (usecs)	328	if (usecs)
331	insert_timeout(&conn->wdata);	329	insert_timeout(&conn->wdata);
332		330
333	conn->wdata.active = 0;	331	conn->wdata.active = 0;
334	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);	332	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
335	/* Futex is up after getting back from async_manager	333	/* Futex is up after getting back from async_manager
336	* get it again */	334	* get it again */
337	futex_down(&async_futex);	335	futex_down(&async_futex);
338	if (usecs && conn->wdata.timedout &&	336	if (usecs && conn->wdata.timedout &&
339	list_empty(&conn->msg_queue)) {	337	list_empty(&conn->msg_queue)) {
340	/* If we timed out-> exit */	338	/* If we timed out-> exit */
341	futex_up(&async_futex);	339	futex_up(&async_futex);
342	return 0;	340	return 0;
343	}	341	}
344	}	342	}
345		343
346	msg = list_get_instance(conn->msg_queue.next, msg_t, link);	344	msg = list_get_instance(conn->msg_queue.next, msg_t, link);
347	list_remove(&msg->link);	345	list_remove(&msg->link);
348	callid = msg->callid;	346	callid = msg->callid;
349	*call = msg->call;	347	*call = msg->call;
350	free(msg);	348	free(msg);
351		349
352	futex_up(&async_futex);	350	futex_up(&async_futex);
353	return callid;	351	return callid;
354	}	352	}
355		353
356	/** Thread function that gets created on new connection	354	/** Fibril function that gets created on new connection
357	*	355	*
358	* This function is defined as a weak symbol - to be redefined in	356	* This function is defined as a weak symbol - to be redefined in
359	* user code.	357	* user code.
360	*/	358	*/
361	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)	359	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
362	{	360	{
363	ipc_answer_fast(callid, ENOENT, 0, 0);	361	ipc_answer_fast(callid, ENOENT, 0, 0);
364	}	362	}
365	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)	363	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
366	{	364	{
367	}	365	}
368		366
369	/** Wrapper for client connection thread	367	/** Wrapper for client connection fibril.
-		368	*
-		369	* When new connection arrives, a fibril with this implementing function is
-		370	* created. It calls client_connection() and does the final cleanup.
370	*	371	*
371	* When new connection arrives, thread with this function is created.	-
372	* It calls client_connection and does final cleanup.	372	* @param arg Connection structure pointer
373	*	373	*
374	* @param arg Connection structure pointer	374	* @return Always zero.
375	*/	375	*/
376	static int connection_fibril(void *arg)	376	static int connection_fibril(void *arg)
377	{	377	{
378	unsigned long key;	378	unsigned long key;
379	msg_t *msg;	379	msg_t *msg;
380	int close_answered = 0;	380	int close_answered = 0;
381		381
382	/* Setup thread local connection pointer */	382	/* Setup fibril-local connection pointer */
383	FIBRIL_connection = (connection_t *) arg;	383	FIBRIL_connection = (connection_t *) arg;
384	FIBRIL_connection->cfibril(FIBRIL_connection->callid,	384	FIBRIL_connection->cfibril(FIBRIL_connection->callid,
385	&FIBRIL_connection->call);	385	&FIBRIL_connection->call);
386		386
387	/* Remove myself from connection hash table */	387	/* Remove myself from connection hash table */
388	futex_down(&async_futex);	388	futex_down(&async_futex);
389	key = FIBRIL_connection->in_phone_hash;	389	key = FIBRIL_connection->in_phone_hash;
390	hash_table_remove(&conn_hash_table, &key, 1);	390	hash_table_remove(&conn_hash_table, &key, 1);
391	futex_up(&async_futex);	391	futex_up(&async_futex);
392		392
393	/* Answer all remaining messages with ehangup */	393	/* Answer all remaining messages with ehangup */
394	while (!list_empty(&FIBRIL_connection->msg_queue)) {	394	while (!list_empty(&FIBRIL_connection->msg_queue)) {
395	msg = list_get_instance(FIBRIL_connection->msg_queue.next,	395	msg = list_get_instance(FIBRIL_connection->msg_queue.next,
396	msg_t, link);	396	msg_t, link);
397	list_remove(&msg->link);	397	list_remove(&msg->link);
398	if (msg->callid == FIBRIL_connection->close_callid)	398	if (msg->callid == FIBRIL_connection->close_callid)
399	close_answered = 1;	399	close_answered = 1;
400	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);	400	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
401	free(msg);	401	free(msg);
402	}	402	}
403	if (FIBRIL_connection->close_callid)	403	if (FIBRIL_connection->close_callid)
404	ipc_answer_fast(FIBRIL_connection->close_callid, 0, 0, 0);	404	ipc_answer_fast(FIBRIL_connection->close_callid, 0, 0, 0);
405		405
406	return 0;	406	return 0;
407	}	407	}
408		408
409	/** Create new thread for a new connection	409	/** Create a new fibril for a new connection.
410	*	410	*
411	* Creates new thread for connection, fills in connection	411	* Creates new fibril for connection, fills in connection structures and inserts
412	* structures and inserts it into the hash table, so that	-
413	* later we can easily do routing of messages to particular	412	* it into the hash table, so that later we can easily do routing of messages to
414	* threads.	413	* particular fibrils.
415	*	414	*
416	* @param in_phone_hash Identification of the incoming connection	415	* @param in_phone_hash Identification of the incoming connection
417	* @param callid Callid of the IPC_M_CONNECT_ME_TO packet	416	* @param callid Callid of the IPC_M_CONNECT_ME_TO packet
418	* @param call Call data of the opening packet	417	* @param call Call data of the opening packet
419	* @param cfibril Fibril function that should be called upon	418	* @param cfibril Fibril function that should be called upon
420	* opening the connection	419	* opening the connection
421	* @return New fibril id.	420	* @return New fibril id.
422	*/	421	*/
423	fid_t async_new_connection(ipcarg_t in_phone_hash, ipc_callid_t callid,	422	fid_t async_new_connection(ipcarg_t in_phone_hash, ipc_callid_t callid,
424	ipc_call_t call, void (cfibril)(ipc_callid_t, ipc_call_t *))	423	ipc_call_t call, void (cfibril)(ipc_callid_t, ipc_call_t *))
425	{	424	{
426	connection_t *conn;	425	connection_t *conn;
427	unsigned long key;	426	unsigned long key;
428		427
429	conn = malloc(sizeof(*conn));	428	conn = malloc(sizeof(*conn));
430	if (!conn) {	429	if (!conn) {
431	ipc_answer_fast(callid, ENOMEM, 0, 0);	430	ipc_answer_fast(callid, ENOMEM, 0, 0);
432	return NULL;	431	return NULL;
433	}	432	}
434	conn->in_phone_hash = in_phone_hash;	433	conn->in_phone_hash = in_phone_hash;
435	list_initialize(&conn->msg_queue);	434	list_initialize(&conn->msg_queue);
436	conn->callid = callid;	435	conn->callid = callid;
437	conn->close_callid = 0;	436	conn->close_callid = 0;
438	if (call)	437	if (call)
439	conn->call = *call;	438	conn->call = *call;
440	conn->wdata.active = 1; /* We will activate it asap */	439	conn->wdata.active = 1; /* We will activate it asap */
441	conn->cfibril = cfibril;	440	conn->cfibril = cfibril;
442		441
443	conn->wdata.fid = fibril_create(connection_fibril, conn);	442	conn->wdata.fid = fibril_create(connection_fibril, conn);
444	if (!conn->wdata.fid) {	443	if (!conn->wdata.fid) {
445	free(conn);	444	free(conn);
446	ipc_answer_fast(callid, ENOMEM, 0, 0);	445	ipc_answer_fast(callid, ENOMEM, 0, 0);
447	return NULL;	446	return NULL;
448	}	447	}
449	/* Add connection to hash table */	448	/* Add connection to hash table */
450	key = conn->in_phone_hash;	449	key = conn->in_phone_hash;
451	futex_down(&async_futex);	450	futex_down(&async_futex);
452	hash_table_insert(&conn_hash_table, &key, &conn->link);	451	hash_table_insert(&conn_hash_table, &key, &conn->link);
453	futex_up(&async_futex);	452	futex_up(&async_futex);
454		453
455	fibril_add_ready(conn->wdata.fid);	454	fibril_add_ready(conn->wdata.fid);
456		455
457	return conn->wdata.fid;	456	return conn->wdata.fid;
458	}	457	}
459		458
460	/** Handle call that was received */	459	/** Handle a call that was received. */
461	static void handle_call(ipc_callid_t callid, ipc_call_t *call)	460	static void handle_call(ipc_callid_t callid, ipc_call_t *call)
462	{	461	{
463	/* Unrouted call - do some default behaviour */	462	/* Unrouted call - do some default behaviour */
464	if ((callid & IPC_CALLID_NOTIFICATION)) {	463	if ((callid & IPC_CALLID_NOTIFICATION)) {
465	in_interrupt_handler = 1;	464	in_interrupt_handler = 1;
466	(*interrupt_received)(callid,call);	465	(*interrupt_received)(callid,call);
467	in_interrupt_handler = 0;	466	in_interrupt_handler = 0;
468	return;	467	return;
469	}	468	}
470		469
471	switch (IPC_GET_METHOD(*call)) {	470	switch (IPC_GET_METHOD(*call)) {
472	case IPC_M_CONNECT_ME_TO:	471	case IPC_M_CONNECT_ME_TO:
473	/* Open new connection with thread etc. */	472	/* Open new connection with fibril etc. */
474	async_new_connection(IPC_GET_ARG3(*call), callid, call,	473	async_new_connection(IPC_GET_ARG3(*call), callid, call,
475	client_connection);	474	client_connection);
476	return;	475	return;
477	}	476	}
478		477
479	/* Try to route call through connection tables */	478	/* Try to route call through connection tables */
480	if (route_call(callid, call))	479	if (route_call(callid, call))
481	return;	480	return;
482		481
483	/* Unknown call from unknown phone - hang it up */	482	/* Unknown call from unknown phone - hang it up */
484	ipc_answer_fast(callid, EHANGUP, 0, 0);	483	ipc_answer_fast(callid, EHANGUP, 0, 0);
485	}	484	}
486		485
487	/** Fire all timeouts that expired	486	/** Fire all timeouts that expired. */
488	*	-
489	*/	-
490	static void handle_expired_timeouts(void)	487	static void handle_expired_timeouts(void)
491	{	488	{
492	struct timeval tv;	489	struct timeval tv;
493	awaiter_t *waiter;	490	awaiter_t *waiter;
494	link_t *cur;	491	link_t *cur;
495		492
496	gettimeofday(&tv,NULL);	493	gettimeofday(&tv,NULL);
497	futex_down(&async_futex);	494	futex_down(&async_futex);

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(root)/trunk/uspace/lib/libc/generic/async.c – Rev 2484 → 2485