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();
 * }
 *
 *
 * my_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 <sys/time.h>
#include <arch/barrier.h>
 
atomic_t async_futex = FUTEX_INITIALIZER;
static hash_table_t conn_hash_table;
static LIST_INITIALIZE(timeout_list);
 
/** Structures of this type represent a waiting fibril. */
typedef struct {
    /** Expiration time. */
    struct timeval expires;    
    /** If true, this struct is in the timeout list. */
    int inlist;
    /** Timeout list link. */
    link_t link;
 
    /** Identification of and link to the waiting fibril. */
    fid_t fid;
    /** If true, this fibril is currently active. */
    int active;
    /** If true, we have timed out. */
    int timedout;
} awaiter_t;
 
typedef struct {
    awaiter_t wdata;
   
    /** If reply was received. */
    int done;
    /** Pointer to where the answer data is stored. */
    ipc_call_t *dataptr;
 
    ipcarg_t retval;
} amsg_t;
 
/**
 * Structures of this type are used to group information about a call and a
 * message queue link.
 */
typedef struct {
    link_t link;
    ipc_callid_t callid;
    ipc_call_t call;
} msg_t;
 
typedef struct {
    awaiter_t wdata;
 
    /** Hash table link. */
    link_t link;
 
    /** Incoming phone hash. */
    ipcarg_t in_phone_hash;    
 
    /** Messages that should be delivered to this fibril. */
    link_t msg_queue;      
                     
    /** Identification of the opening call. */
    ipc_callid_t callid;
    /** Call data of the opening call. */
    ipc_call_t call;
 
    /** Identification of the closing call. */
    ipc_callid_t close_callid;
 
    /** Fibril function that will be used to handle the connection. */
    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);
 
/**
 * Pointer to a fibril function that will be used to handle connections.
 */
static async_client_conn_t client_connection = default_client_connection;
/**
 * Pointer to a fibril function that will be used to handle interrupt
 * notifications.
 */
static async_client_conn_t interrupt_received = default_interrupt_received;
 
#define CONN_HASH_TABLE_CHAINS  32
 
/** Compute hash into the connection hash table based on the source phone hash.
 *
 * @param key       Pointer to source phone hash.
 *
 * @return      Index into the connection hash table.
 */
static hash_index_t conn_hash(unsigned long *key)
{
    assert(key);
    return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;
}
 
/** Compare hash table item with a key.
 *
 * @param key       Array containing the source phone hash as the only item.
 * @param keys      Expected 1 but ignored.
 * @param item      Connection hash table item.
 *
 * @return      True on match, false otherwise.
 */
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;
}
 
/** Connection hash table removal callback function.
 *
 * This function is called whenever a connection is removed from the connection
 * hash table.
 *
 * @param item      Connection hash table item being removed.
 */
static void conn_remove(link_t *item)
{
    free(hash_table_get_instance(item, connection_t, link));
}
 
 
/** Operations for the connection hash table. */
static hash_table_operations_t conn_hash_table_ops = {
    .hash = conn_hash,
    .compare = conn_compare,
    .remove_callback = conn_remove
};
 
/** Sort in current fibril's timeout request.
 *
 * @param wd        Wait data of the current fibril.
 */
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.
 *
 * If the proper connection fibril is found, a message with the call is added to
 * its message queue. If the fibril was not active, it is activated and all
 * timeouts are unregistered.
 *
 * @param callid    Hash of the incoming call.
 * @param call      Data of the incoming call.
 *
 * @return      Zero if the call doesn't match any connection.
 *          One if the call was passed to the respective 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 connection fibril is waiting for an event, activate 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.
 *
 * @param call      Storage where the incoming call data will be stored.
 * @param usecs     Timeout in microseconds. Zero denotes no timeout.
 *
 * @return      If no timeout was specified, then a hash of the
 *          incoming call is returned. If a timeout is specified,
 *          then a hash of the incoming call is returned unless
 *          the timeout expires prior to receiving a message. In
 *          that case zero is returned.
 */
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
     *           a 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 arrives */
    while (list_empty(&conn->msg_queue)) {
        if (usecs)
            insert_timeout(&conn->wdata);
 
        conn->wdata.active = 0;
        /*
         * Note: the current fibril will be rescheduled either due to a
         * timeout or due to an arriving message destined to it. In the
         * former case, handle_expired_timeouts() and, in the latter
         * case, route_call() will perform the wakeup.
         */
        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;
}
 
/** Default fibril function that gets called to handle new connection.
 *
 * This function is defined as a weak symbol - to be redefined in user code.
 *
 * @param callid    Hash of the incoming call.
 * @param call      Data of the incoming call.
 */
static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
{
    ipc_answer_fast(callid, ENOENT, 0, 0);
}
 
/** Default fibril function that gets called to handle interrupt notifications.
 *
 * @param callid    Hash of the incoming call.
 * @param call      Data of the incoming call.
 */
static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
{
}
 
/** Wrapper for client connection fibril.
 *
 * When a 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 the 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    Hash of the opening IPC_M_CONNECT_ME_TO call.
 * @param call      Call data of the opening call.
 * @param cfibril   Fibril function that should be called upon opening the
 *          connection.
 *
 * @return      New fibril id or NULL on failure.
 */
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 the fibril 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 the connection 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.
 *
 * If the call has the IPC_M_CONNECT_ME_TO method, a new connection is created.
 * Otherwise the call is routed to its connection fibril.
 *
 * @param callid    Hash of the incoming call.
 * @param call      Data of the incoming call.
 */
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 the call through the connection hash table */
    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.
 *
 * @return      Never returns.
 */
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 a 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.
 *
 * @param arg       Unused.
 *
 * @return      Never returns.
 */
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 the async framework.
 *
 * @return      Zero on success or an error code.
 */
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;
}
 
/** Reply received callback.
 *
 * This function is called whenever a reply for an asynchronous message sent out
 * by the asynchronous framework is received.
 *
 * Notify the fibril which is waiting for this message that it has arrived.
 *
 * @param private   Pointer to the asynchronous message record.
 * @param retval    Value returned in the answer.
 * @param data      Call data of the answer.
 */
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.
 *
 * @param phoneid   Handle of the phone that will be used for the send.
 * @param method    Service-defined method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param dataptr   If non-NULL, storage where the reply data will be
 *          stored.
 *
 * @return      Hash of the sent message.
 */
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;
 
    /* We may sleep in the next method, but it will use its own mechanism */
    msg->wdata.active = 1;
               
    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.
 *
 * @param phoneid   Handle of the phone that will be used for the send.
 * @param method    Service-defined method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param dataptr   If non-NULL, storage where the reply data will be
 *          stored.
 *
 * @return      Hash of the sent message.
 */
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;
 
    /* We may sleep in next method, but it will use its own mechanism */
    msg->wdata.active = 1;
               
    ipc_call_async_3(phoneid, method, arg1, arg2, arg3, msg, reply_received,
        1);
 
    return (aid_t) msg;
}
 
/** Wait for a message sent by the async framework.
 *
 * @param amsgid    Hash of the message to wait for.
 * @param retval    Pointer to storage where the retval of the answer will
 *          be stored.
 */
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 the async_futex locked 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 the async framework, timeout variant.
 *
 * @param amsgid    Hash of the message to wait for.
 * @param retval    Pointer to storage where the retval of the answer will
 *          be stored.
 * @param timeout   Timeout in microseconds.
 *
 * @return      Zero on success, ETIMEOUT if the timeout has 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 the async_futex locked 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 for specified time.
 *
 * The current fibril is suspended but the thread continues to execute.
 *
 * @param timeout   Duration of the wait in microseconds.
 */
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 the async_futex locked when entering this function */
    fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
    /* futex is up automatically after fibril_schedule_next_adv()...*/
    free(msg);
}
 
/** Setter for client_connection function pointer.
 *
 * @param conn      Function that will implement a new connection fibril.
 */
void async_set_client_connection(async_client_conn_t conn)
{
    client_connection = conn;
}
 
/** Setter for interrupt_received function pointer.
 *
 * @param conn      Function that will implement a new interrupt
 *          notification fibril.
 */
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 2490	Rev 2492
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	* my_client_connection(icallid, *icall)	75	* my_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 <sys/time.h>	102	#include <sys/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	/** Structures of this type represent a waiting fibril. */	109	/** Structures of this type represent a waiting fibril. */
110	typedef struct {	110	typedef struct {
111	/** Expiration time. */	111	/** Expiration time. */
112	struct timeval expires;	112	struct timeval expires;
113	/** If true, this struct is in the timeout list. */	113	/** If true, this struct is in the timeout list. */
114	int inlist;	114	int inlist;
115	/** Timeout list link. */	115	/** Timeout list link. */
116	link_t link;	116	link_t link;
117		117
118	/** Identification of and link to the waiting fibril. */	118	/** Identification of and link to the waiting fibril. */
119	fid_t fid;	119	fid_t fid;
120	/** If true, this fibril is currently active. */	120	/** If true, this fibril is currently active. */
121	int active;	121	int active;
122	/** If true, we have timed out. */	122	/** If true, we have timed out. */
123	int timedout;	123	int timedout;
124	} awaiter_t;	124	} awaiter_t;
125		125
126	typedef struct {	126	typedef struct {
127	awaiter_t wdata;	127	awaiter_t wdata;
128		128
129	/** If reply was received. */	129	/** If reply was received. */
130	int done;	130	int done;
131	/** Pointer to where the answer data is stored. */	131	/** Pointer to where the answer data is stored. */
132	ipc_call_t *dataptr;	132	ipc_call_t *dataptr;
133		133
134	ipcarg_t retval;	134	ipcarg_t retval;
135	} amsg_t;	135	} amsg_t;
136		136
137	/**	137	/**
138	* Structures of this type are used to group information about a call and a	138	* Structures of this type are used to group information about a call and a
139	* message queue link.	139	* message queue link.
140	*/	140	*/
141	typedef struct {	141	typedef struct {
142	link_t link;	142	link_t link;
143	ipc_callid_t callid;	143	ipc_callid_t callid;
144	ipc_call_t call;	144	ipc_call_t call;
145	} msg_t;	145	} msg_t;
146		146
147	typedef struct {	147	typedef struct {
148	awaiter_t wdata;	148	awaiter_t wdata;
149		149
150	/** Hash table link. */	150	/** Hash table link. */
151	link_t link;	151	link_t link;
152		152
153	/** Incoming phone hash. */	153	/** Incoming phone hash. */
154	ipcarg_t in_phone_hash;	154	ipcarg_t in_phone_hash;
155		155
156	/** Messages that should be delivered to this fibril. */	156	/** Messages that should be delivered to this fibril. */
157	link_t msg_queue;	157	link_t msg_queue;
158		158
159	/** Identification of the opening call. */	159	/** Identification of the opening call. */
160	ipc_callid_t callid;	160	ipc_callid_t callid;
161	/** Call data of the opening call. */	161	/** Call data of the opening call. */
162	ipc_call_t call;	162	ipc_call_t call;
163		163
164	/** Identification of the closing call. */	164	/** Identification of the closing call. */
165	ipc_callid_t close_callid;	165	ipc_callid_t close_callid;
166		166
167	/** Fibril function that will be used to handle the connection. */	167	/** Fibril function that will be used to handle the connection. */
168	void (cfibril)(ipc_callid_t, ipc_call_t );	168	void (cfibril)(ipc_callid_t, ipc_call_t );
169	} connection_t;	169	} connection_t;
170		170
171	/** Identifier of the incoming connection handled by the current fibril. */	171	/** Identifier of the incoming connection handled by the current fibril. */
172	__thread connection_t *FIBRIL_connection;	172	__thread connection_t *FIBRIL_connection;
173		173
174	/**	174	/**
175	* If true, it is forbidden to use async_req functions and all preemption is	175	* If true, it is forbidden to use async_req functions and all preemption is
176	* disabled.	176	* disabled.
177	*/	177	*/
178	__thread int in_interrupt_handler;	178	__thread int in_interrupt_handler;
179		179
180	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);	180	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);
181	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);	181	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);
182		182
183	/**	183	/**
184	* Pointer to a fibril function that will be used to handle connections.	184	* Pointer to a fibril function that will be used to handle connections.
185	*/	185	*/
186	static async_client_conn_t client_connection = default_client_connection;	186	static async_client_conn_t client_connection = default_client_connection;
187	/**	187	/**
188	* Pointer to a fibril function that will be used to handle interrupt	188	* Pointer to a fibril function that will be used to handle interrupt
189	* notifications.	189	* notifications.
190	*/	190	*/
191	static async_client_conn_t interrupt_received = default_interrupt_received;	191	static async_client_conn_t interrupt_received = default_interrupt_received;
192		192
193	#define CONN_HASH_TABLE_CHAINS 32	193	#define CONN_HASH_TABLE_CHAINS 32
194		194
195	/** Compute hash into the connection hash table based on the source phone hash.	195	/** Compute hash into the connection hash table based on the source phone hash.
196	*	196	*
197	* @param key Pointer to source phone hash.	197	* @param key Pointer to source phone hash.
198	*	198	*
199	* @return Index into the connection hash table.	199	* @return Index into the connection hash table.
200	*/	200	*/
201	static hash_index_t conn_hash(unsigned long *key)	201	static hash_index_t conn_hash(unsigned long *key)
202	{	202	{
203	assert(key);	203	assert(key);
204	return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;	204	return ((*key) >> 4) % CONN_HASH_TABLE_CHAINS;
205	}	205	}
206		206
207	/** Compare hash table item with a key.	207	/** Compare hash table item with a key.
208	*	208	*
209	* @param key Array containing the source phone hash as the only item.	209	* @param key Array containing the source phone hash as the only item.
210	* @param keys Expected 1 but ignored.	210	* @param keys Expected 1 but ignored.
211	* @param item Connection hash table item.	211	* @param item Connection hash table item.
212	*	212	*
213	* @return True on match, false otherwise.	213	* @return True on match, false otherwise.
214	*/	214	*/
215	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)	215	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)
216	{	216	{
217	connection_t *hs;	217	connection_t *hs;
218		218
219	hs = hash_table_get_instance(item, connection_t, link);	219	hs = hash_table_get_instance(item, connection_t, link);
220		220
221	return key[0] == hs->in_phone_hash;	221	return key[0] == hs->in_phone_hash;
222	}	222	}
223		223
224	/** Connection hash table removal callback function.	224	/** Connection hash table removal callback function.
225	*	225	*
226	* This function is called whenever a connection is removed from the connection	226	* This function is called whenever a connection is removed from the connection
227	* hash table.	227	* hash table.
228	*	228	*
229	* @param item Connection hash table item being removed.	229	* @param item Connection hash table item being removed.
230	*/	230	*/
231	static void conn_remove(link_t *item)	231	static void conn_remove(link_t *item)
232	{	232	{
233	free(hash_table_get_instance(item, connection_t, link));	233	free(hash_table_get_instance(item, connection_t, link));
234	}	234	}
235		235
236		236
237	/** Operations for the connection hash table. */	237	/** Operations for the connection hash table. */
238	static hash_table_operations_t conn_hash_table_ops = {	238	static hash_table_operations_t conn_hash_table_ops = {
239	.hash = conn_hash,	239	.hash = conn_hash,
240	.compare = conn_compare,	240	.compare = conn_compare,
241	.remove_callback = conn_remove	241	.remove_callback = conn_remove
242	};	242	};
243		243
244	/** Sort in current fibril's timeout request.	244	/** Sort in current fibril's timeout request.
245	*	245	*
246	* @param wd Wait data of the current fibril.	246	* @param wd Wait data of the current fibril.
247	*/	247	*/
248	static void insert_timeout(awaiter_t *wd)	248	static void insert_timeout(awaiter_t *wd)
249	{	249	{
250	link_t *tmp;	250	link_t *tmp;
251	awaiter_t *cur;	251	awaiter_t *cur;
252		252
253	wd->timedout = 0;	253	wd->timedout = 0;
254	wd->inlist = 1;	254	wd->inlist = 1;
255		255
256	tmp = timeout_list.next;	256	tmp = timeout_list.next;
257	while (tmp != &timeout_list) {	257	while (tmp != &timeout_list) {
258	cur = list_get_instance(tmp, awaiter_t, link);	258	cur = list_get_instance(tmp, awaiter_t, link);
259	if (tv_gteq(&cur->expires, &wd->expires))	259	if (tv_gteq(&cur->expires, &wd->expires))
260	break;	260	break;
261	tmp = tmp->next;	261	tmp = tmp->next;
262	}	262	}
263	list_append(&wd->link, tmp);	263	list_append(&wd->link, tmp);
264	}	264	}
265		265
266	/** Try to route a call to an appropriate connection fibril.	266	/** Try to route a call to an appropriate connection fibril.
267	*	267	*
268	* If the proper connection fibril is found, a message with the call is added to	268	* If the proper connection fibril is found, a message with the call is added to
269	* its message queue. If the fibril was not active, it is activated and all	269	* its message queue. If the fibril was not active, it is activated and all
270	* timeouts are unregistered.	270	* timeouts are unregistered.
271	*	271	*
272	* @param callid Hash of the incoming call.	272	* @param callid Hash of the incoming call.
273	* @param call Data of the incoming call.	273	* @param call Data of the incoming call.
274	*	274	*
275	* @return Zero if the call doesn't match any connection.	275	* @return Zero if the call doesn't match any connection.
276	* One if the call was passed to the respective connection	276	* One if the call was passed to the respective connection
277	* fibril.	277	* fibril.
278	*/	278	*/
279	static int route_call(ipc_callid_t callid, ipc_call_t *call)	279	static int route_call(ipc_callid_t callid, ipc_call_t *call)
280	{	280	{
281	connection_t *conn;	281	connection_t *conn;
282	msg_t *msg;	282	msg_t *msg;
283	link_t *hlp;	283	link_t *hlp;
284	unsigned long key;	284	unsigned long key;
285		285
286	futex_down(&async_futex);	286	futex_down(&async_futex);
287		287
288	key = call->in_phone_hash;	288	key = call->in_phone_hash;
289	hlp = hash_table_find(&conn_hash_table, &key);	289	hlp = hash_table_find(&conn_hash_table, &key);
290	if (!hlp) {	290	if (!hlp) {
291	futex_up(&async_futex);	291	futex_up(&async_futex);
292	return 0;	292	return 0;
293	}	293	}
294	conn = hash_table_get_instance(hlp, connection_t, link);	294	conn = hash_table_get_instance(hlp, connection_t, link);
295		295
296	msg = malloc(sizeof(*msg));	296	msg = malloc(sizeof(*msg));
297	msg->callid = callid;	297	msg->callid = callid;
298	msg->call = *call;	298	msg->call = *call;
299	list_append(&msg->link, &conn->msg_queue);	299	list_append(&msg->link, &conn->msg_queue);
300		300
301	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)	301	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)
302	conn->close_callid = callid;	302	conn->close_callid = callid;
303		303
304	/* If the connection fibril is waiting for an event, activate it */	304	/* If the connection fibril is waiting for an event, activate it */
305	if (!conn->wdata.active) {	305	if (!conn->wdata.active) {
306	/* If in timeout list, remove it */	306	/* If in timeout list, remove it */
307	if (conn->wdata.inlist) {	307	if (conn->wdata.inlist) {
308	conn->wdata.inlist = 0;	308	conn->wdata.inlist = 0;
309	list_remove(&conn->wdata.link);	309	list_remove(&conn->wdata.link);
310	}	310	}
311	conn->wdata.active = 1;	311	conn->wdata.active = 1;
312	fibril_add_ready(conn->wdata.fid);	312	fibril_add_ready(conn->wdata.fid);
313	}	313	}
314		314
315	futex_up(&async_futex);	315	futex_up(&async_futex);
316		316
317	return 1;	317	return 1;
318	}	318	}
319		319
320	/** Return new incoming message for the current (fibril-local) connection.	320	/** Return new incoming message for the current (fibril-local) connection.
321	*	321	*
322	* @param call Storage where the incoming call data will be stored.	322	* @param call Storage where the incoming call data will be stored.
323	* @param usecs Timeout in microseconds. Zero denotes no timeout.	323	* @param usecs Timeout in microseconds. Zero denotes no timeout.
324	*	324	*
325	* @return If no timeout was specified, then a hash of the	325	* @return If no timeout was specified, then a hash of the
326	* incoming call is returned. If a timeout is specified,	326	* incoming call is returned. If a timeout is specified,
327	* then a hash of the incoming call is returned unless	327	* then a hash of the incoming call is returned unless
328	* the timeout expires prior to receiving a message. In	328	* the timeout expires prior to receiving a message. In
329	* that case zero is returned.	329	* that case zero is returned.
330	*/	330	*/
331	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)	331	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)
332	{	332	{
333	msg_t *msg;	333	msg_t *msg;
334	ipc_callid_t callid;	334	ipc_callid_t callid;
335	connection_t *conn;	335	connection_t *conn;
336		336
337	assert(FIBRIL_connection);	337	assert(FIBRIL_connection);
338	/* GCC 4.1.0 coughs on FIBRIL_connection-> dereference,	338	/* GCC 4.1.0 coughs on FIBRIL_connection-> dereference,
339	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.	339	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.
340	* I would never expect to find so many errors in	340	* I would never expect to find so many errors in
341	* a compiler ($&$(&$	341	* a compiler ($&$(&$
342	*/	342	*/
343	conn = FIBRIL_connection;	343	conn = FIBRIL_connection;
344		344
345	futex_down(&async_futex);	345	futex_down(&async_futex);
346		346
347	if (usecs) {	347	if (usecs) {
348	gettimeofday(&conn->wdata.expires, NULL);	348	gettimeofday(&conn->wdata.expires, NULL);
349	tv_add(&conn->wdata.expires, usecs);	349	tv_add(&conn->wdata.expires, usecs);
350	} else {	350	} else {
351	conn->wdata.inlist = 0;	351	conn->wdata.inlist = 0;
352	}	352	}
353	/* If nothing in queue, wait until something arrives */	353	/* If nothing in queue, wait until something arrives */
354	while (list_empty(&conn->msg_queue)) {	354	while (list_empty(&conn->msg_queue)) {
355	if (usecs)	355	if (usecs)
356	insert_timeout(&conn->wdata);	356	insert_timeout(&conn->wdata);
357		357
358	conn->wdata.active = 0;	358	conn->wdata.active = 0;
-		359	/*
-		360	* Note: the current fibril will be rescheduled either due to a
-		361	* timeout or due to an arriving message destined to it. In the
-		362	* former case, handle_expired_timeouts() and, in the latter
-		363	* case, route_call() will perform the wakeup.
-		364	*/
359	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);	365	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
360	/*	366	/*
361	* Futex is up after getting back from async_manager get it	367	* Futex is up after getting back from async_manager get it
362	* again.	368	* again.
363	*/	369	*/
364	futex_down(&async_futex);	370	futex_down(&async_futex);
365	if (usecs && conn->wdata.timedout &&	371	if (usecs && conn->wdata.timedout &&
366	list_empty(&conn->msg_queue)) {	372	list_empty(&conn->msg_queue)) {
367	/* If we timed out -> exit */	373	/* If we timed out -> exit */
368	futex_up(&async_futex);	374	futex_up(&async_futex);
369	return 0;	375	return 0;
370	}	376	}
371	}	377	}
372		378
373	msg = list_get_instance(conn->msg_queue.next, msg_t, link);	379	msg = list_get_instance(conn->msg_queue.next, msg_t, link);
374	list_remove(&msg->link);	380	list_remove(&msg->link);
375	callid = msg->callid;	381	callid = msg->callid;
376	*call = msg->call;	382	*call = msg->call;
377	free(msg);	383	free(msg);
378		384
379	futex_up(&async_futex);	385	futex_up(&async_futex);
380	return callid;	386	return callid;
381	}	387	}
382		388
383	/** Default fibril function that gets called to handle new connection.	389	/** Default fibril function that gets called to handle new connection.
384	*	390	*
385	* This function is defined as a weak symbol - to be redefined in user code.	391	* This function is defined as a weak symbol - to be redefined in user code.
386	*	392	*
387	* @param callid Hash of the incoming call.	393	* @param callid Hash of the incoming call.
388	* @param call Data of the incoming call.	394	* @param call Data of the incoming call.
389	*/	395	*/
390	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)	396	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
391	{	397	{
392	ipc_answer_fast(callid, ENOENT, 0, 0);	398	ipc_answer_fast(callid, ENOENT, 0, 0);
393	}	399	}
394		400
395	/** Default fibril function that gets called to handle interrupt notifications.	401	/** Default fibril function that gets called to handle interrupt notifications.
396	*	402	*
397	* @param callid Hash of the incoming call.	403	* @param callid Hash of the incoming call.
398	* @param call Data of the incoming call.	404	* @param call Data of the incoming call.
399	*/	405	*/
400	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)	406	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
401	{	407	{
402	}	408	}
403		409
404	/** Wrapper for client connection fibril.	410	/** Wrapper for client connection fibril.
405	*	411	*
406	* When a new connection arrives, a fibril with this implementing function is	412	* When a new connection arrives, a fibril with this implementing function is
407	* created. It calls client_connection() and does the final cleanup.	413	* created. It calls client_connection() and does the final cleanup.
408	*	414	*
409	* @param arg Connection structure pointer.	415	* @param arg Connection structure pointer.
410	*	416	*
411	* @return Always zero.	417	* @return Always zero.
412	*/	418	*/
413	static int connection_fibril(void *arg)	419	static int connection_fibril(void *arg)
414	{	420	{
415	unsigned long key;	421	unsigned long key;
416	msg_t *msg;	422	msg_t *msg;
417	int close_answered = 0;	423	int close_answered = 0;
418		424
419	/* Setup fibril-local connection pointer */	425	/* Setup fibril-local connection pointer */
420	FIBRIL_connection = (connection_t *) arg;	426	FIBRIL_connection = (connection_t *) arg;
421	FIBRIL_connection->cfibril(FIBRIL_connection->callid,	427	FIBRIL_connection->cfibril(FIBRIL_connection->callid,
422	&FIBRIL_connection->call);	428	&FIBRIL_connection->call);
423		429
424	/* Remove myself from the connection hash table */	430	/* Remove myself from the connection hash table */
425	futex_down(&async_futex);	431	futex_down(&async_futex);
426	key = FIBRIL_connection->in_phone_hash;	432	key = FIBRIL_connection->in_phone_hash;
427	hash_table_remove(&conn_hash_table, &key, 1);	433	hash_table_remove(&conn_hash_table, &key, 1);
428	futex_up(&async_futex);	434	futex_up(&async_futex);
429		435
430	/* Answer all remaining messages with EHANGUP */	436	/* Answer all remaining messages with EHANGUP */
431	while (!list_empty(&FIBRIL_connection->msg_queue)) {	437	while (!list_empty(&FIBRIL_connection->msg_queue)) {
432	msg = list_get_instance(FIBRIL_connection->msg_queue.next,	438	msg = list_get_instance(FIBRIL_connection->msg_queue.next,
433	msg_t, link);	439	msg_t, link);
434	list_remove(&msg->link);	440	list_remove(&msg->link);
435	if (msg->callid == FIBRIL_connection->close_callid)	441	if (msg->callid == FIBRIL_connection->close_callid)
436	close_answered = 1;	442	close_answered = 1;
437	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);	443	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
438	free(msg);	444	free(msg);
439	}	445	}
440	if (FIBRIL_connection->close_callid)	446	if (FIBRIL_connection->close_callid)
441	ipc_answer_fast(FIBRIL_connection->close_callid, 0, 0, 0);	447	ipc_answer_fast(FIBRIL_connection->close_callid, 0, 0, 0);
442		448
443	return 0;	449	return 0;
444	}	450	}
445		451
446	/** Create a new fibril for a new connection.	452	/** Create a new fibril for a new connection.
447	*	453	*
448	* Creates new fibril for connection, fills in connection structures and inserts	454	* Creates new fibril for connection, fills in connection structures and inserts
449	* it into the hash table, so that later we can easily do routing of messages to	455	* it into the hash table, so that later we can easily do routing of messages to
450	* particular fibrils.	456	* particular fibrils.
451	*	457	*
452	* @param in_phone_hash Identification of the incoming connection.	458	* @param in_phone_hash Identification of the incoming connection.
453	* @param callid Hash of the opening IPC_M_CONNECT_ME_TO call.	459	* @param callid Hash of the opening IPC_M_CONNECT_ME_TO call.
454	* @param call Call data of the opening call.	460	* @param call Call data of the opening call.
455	* @param cfibril Fibril function that should be called upon opening the	461	* @param cfibril Fibril function that should be called upon opening the
456	* connection.	462	* connection.
457	*	463	*
458	* @return New fibril id or NULL on failure.	464	* @return New fibril id or NULL on failure.
459	*/	465	*/
460	fid_t async_new_connection(ipcarg_t in_phone_hash, ipc_callid_t callid,	466	fid_t async_new_connection(ipcarg_t in_phone_hash, ipc_callid_t callid,
461	ipc_call_t call, void (cfibril)(ipc_callid_t, ipc_call_t *))	467	ipc_call_t call, void (cfibril)(ipc_callid_t, ipc_call_t *))
462	{	468	{
463	connection_t *conn;	469	connection_t *conn;
464	unsigned long key;	470	unsigned long key;
465		471
466	conn = malloc(sizeof(*conn));	472	conn = malloc(sizeof(*conn));
467	if (!conn) {	473	if (!conn) {
468	ipc_answer_fast(callid, ENOMEM, 0, 0);	474	ipc_answer_fast(callid, ENOMEM, 0, 0);
469	return NULL;	475	return NULL;
470	}	476	}
471	conn->in_phone_hash = in_phone_hash;	477	conn->in_phone_hash = in_phone_hash;
472	list_initialize(&conn->msg_queue);	478	list_initialize(&conn->msg_queue);
473	conn->callid = callid;	479	conn->callid = callid;
474	conn->close_callid = 0;	480	conn->close_callid = 0;
475	if (call)	481	if (call)
476	conn->call = *call;	482	conn->call = *call;
477	conn->wdata.active = 1; /* We will activate the fibril ASAP */	483	conn->wdata.active = 1; /* We will activate the fibril ASAP */
478	conn->cfibril = cfibril;	484	conn->cfibril = cfibril;
479		485
480	conn->wdata.fid = fibril_create(connection_fibril, conn);	486	conn->wdata.fid = fibril_create(connection_fibril, conn);
481	if (!conn->wdata.fid) {	487	if (!conn->wdata.fid) {
482	free(conn);	488	free(conn);
483	ipc_answer_fast(callid, ENOMEM, 0, 0);	489	ipc_answer_fast(callid, ENOMEM, 0, 0);
484	return NULL;	490	return NULL;
485	}	491	}
486	/* Add connection to the connection hash table */	492	/* Add connection to the connection hash table */
487	key = conn->in_phone_hash;	493	key = conn->in_phone_hash;
488	futex_down(&async_futex);	494	futex_down(&async_futex);
489	hash_table_insert(&conn_hash_table, &key, &conn->link);	495	hash_table_insert(&conn_hash_table, &key, &conn->link);
490	futex_up(&async_futex);	496	futex_up(&async_futex);
491		497
492	fibril_add_ready(conn->wdata.fid);	498	fibril_add_ready(conn->wdata.fid);
493		499
494	return conn->wdata.fid;	500	return conn->wdata.fid;

Subversion Repositories HelenOS

(root)/trunk/uspace/lib/libc/generic/async.c @ 4718 – Rev 2490 → 2492