WebSVN – HelenOS – Diff – /tags/0.2.0.1/uspace/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:
 * - 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:
 *
 * 1) Multithreaded client application
 *  create_thread(thread1);
 *  create_thread(thread2);
 *  ...
 *  
 *  thread1() {
 *        conn = ipc_connect_me_to();
 *        c1 = send(conn);
 *        c2 = send(conn);
 *        wait_for(c1);
 *        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, 0, 0, 0);
 *
 *       callid = async_get_call(&call);
 *       handle(callid, call);
 *       ipc_answer_fast(callid, 1,2,3);
 *
 *       callid = async_get_call(&call);
 *       ....
 * }
 *
 * TODO: Detaching/joining dead psthreads?
 */
#include <futex.h>
#include <async.h>
#include <psthread.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 {
    struct timeval expires;      /**< Expiration time for waiting thread */
    int inlist;             /**< If true, this struct is in timeout list */
    link_t link;
 
    pstid_t ptid;                /**< Thread waiting for this message */
    int active;                  /**< If this thread is currently active */
    int timedout;                /**< If true, we timed out */
} 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 thread */
    /* Structures for connection opening packet */
    ipc_callid_t callid;
    ipc_call_t call;
    ipc_callid_t close_callid; /* Identification of closing packet */
    void (*cthread)(ipc_callid_t,ipc_call_t *);
} connection_t;
 
/** Identifier of incoming connection handled by current thread */
__thread connection_t *PS_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 thread
 *
 */
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;
        psthread_add_ready(conn->wdata.ptid);
    }
 
    futex_up(&async_futex);
 
    return 1;
}
 
/** Return new incoming message for current(thread-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(PS_connection);
    /* GCC 4.1.0 coughs on PS_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 = PS_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;
        psthread_schedule_next_adv(PS_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;
}
 
/** Thread 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 thread
 *
 * When new connection arrives, thread with this function is created.
 * It calls client_connection and does final cleanup.
 *
 * @param arg Connection structure pointer
 */
static int connection_thread(void  *arg)
{
    unsigned long key;
    msg_t *msg;
    int close_answered = 0;
 
    /* Setup thread local connection pointer */
    PS_connection = (connection_t *)arg;
    PS_connection->cthread(PS_connection->callid, &PS_connection->call);
    /* Remove myself from connection hash table */
    futex_down(&async_futex);
    key = PS_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(&PS_connection->msg_queue)) {
        msg = list_get_instance(PS_connection->msg_queue.next, msg_t, link);
        list_remove(&msg->link);
        if (msg->callid == PS_connection->close_callid)
            close_answered = 1;
        ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
        free(msg);
    }
    if (PS_connection->close_callid)
        ipc_answer_fast(PS_connection->close_callid, 0, 0, 0);
}
 
/** Create new thread for a new connection
 *
 * Creates new thread 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
 * threads.
 *
 * @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 cthread Thread function that should be called upon
 *                opening the connection
 * @return New thread id
 */
pstid_t async_new_connection(ipcarg_t in_phone_hash,ipc_callid_t callid,
                 ipc_call_t *call,
                 void (*cthread)(ipc_callid_t,ipc_call_t *))
{
    pstid_t ptid;
    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->cthread = cthread;
 
    conn->wdata.ptid = psthread_create(connection_thread, conn);
    if (!conn->wdata.ptid) {
        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);
 
    psthread_add_ready(conn->wdata.ptid);
 
    return conn->wdata.ptid;
}
 
/** Handle 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 thread 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 thread should not
         * be active when it gets here.
         */
        if (!waiter->active) {
            waiter->active = 1;
            psthread_add_ready(waiter->ptid);
        }
    }
 
    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 (psthread_schedule_next_adv(PS_FROM_MANAGER)) {
            futex_up(&async_futex); /* async_futex is always held
                        * when entering manager thread
                        */
            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);
    }
}
 
/** Function to start async_manager as a standalone thread
 *
 * When more kernel threads are used, one async manager should
 * exist per thread. The particular implementation may change,
 * currently one async_manager is started automatically per kernel
 * thread except main thread.
 */
static int async_manager_thread(void *arg)
{
    futex_up(&async_futex); /* async_futex is always locked when entering
                * manager */
    async_manager_worker();
}
 
/** Add one manager to manager list */
void async_create_manager(void)
{
    pstid_t ptid;
 
    ptid = psthread_create(async_manager_thread, NULL);
    psthread_add_manager(ptid);
}
 
/** Remove one manager from manager list */
void async_destroy_manager(void)
{
    psthread_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;
    }
   
}
 
/** IPC handler for messages in async framework
 *
 * Notify thread that 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;
        psthread_add_ready(msg->wdata.ptid);
    }
    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 asynchronou 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 asynchronou 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;
    connection_t *conn;
 
    futex_down(&async_futex);
    if (msg->done) {
        futex_up(&async_futex);
        goto done;
    }
 
    msg->wdata.ptid = psthread_get_id();
    msg->wdata.active = 0;
    msg->wdata.inlist = 0;
    /* Leave locked async_futex when entering this function */
    psthread_schedule_next_adv(PS_TO_MANAGER);
    /* futex is up automatically after psthread_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;
    connection_t *conn;
 
    /* 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.ptid = psthread_get_id();
    msg->wdata.active = 0;
    insert_timeout(&msg->wdata);
 
    /* Leave locked async_futex when entering this function */
    psthread_schedule_next_adv(PS_TO_MANAGER);
    /* futex is up automatically after psthread_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.ptid = psthread_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 async_futex when entering this function */
    psthread_schedule_next_adv(PS_TO_MANAGER);
    /* futex is up automatically after psthread_schedule_next...*/
    free(msg);
}
 
/** Set function that is called, IPC_M_CONNECT_ME_TO is received
 *
 * @param conn Function that will form new psthread.
 */
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 1965	Rev 1968
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	38	* The aim of this library is facilitating writing programs utilizing
39	* the asynchronous nature of Helenos IPC, yet using a normal way	39	* the asynchronous nature of Helenos IPC, yet using a normal way
40	* of programming.	40	* of programming.
41	*	41	*
42	* You should be able to write very simple multithreaded programs,	42	* You should be able to write very simple multithreaded programs,
43	* the async framework will automatically take care of most synchronization	43	* the async framework will automatically take care of most synchronization
44	* problems.	44	* problems.
45	*	45	*
46	* Default semantics:	46	* Default semantics:
47	* - send() - send asynchronously. If the kernel refuses to send more	47	* - send() - send asynchronously. If the kernel refuses to send more
48	* messages, [ try to get responses from kernel, if nothing	48	* messages, [ try to get responses from kernel, if nothing
49	* found, might try synchronous ]	49	* found, might try synchronous ]
50	*	50	*
51	* Example of use:	51	* Example of use:
52	*	52	*
53	* 1) Multithreaded client application	53	* 1) Multithreaded client application
54	* create_thread(thread1);	54	* create_thread(thread1);
55	* create_thread(thread2);	55	* create_thread(thread2);
56	* ...	56	* ...
57	*	57	*
58	* thread1() {	58	* thread1() {
59	* conn = ipc_connect_me_to();	59	* conn = ipc_connect_me_to();
60	* c1 = send(conn);	60	* c1 = send(conn);
61	* c2 = send(conn);	61	* c2 = send(conn);
62	* wait_for(c1);	62	* wait_for(c1);
63	* wait_for(c2);	63	* wait_for(c2);
64	* }	64	* }
65	*	65	*
66	*	66	*
67	* 2) Multithreaded server application	67	* 2) Multithreaded server application
68	* main() {	68	* main() {
69	* async_manager();	69	* async_manager();
70	* }	70	* }
71	*	71	*
72	*	72	*
73	* client_connection(icallid, *icall) {	73	* client_connection(icallid, *icall) {
74	* if (want_refuse) {	74	* if (want_refuse) {
75	* ipc_answer_fast(icallid, ELIMIT, 0, 0);	75	* ipc_answer_fast(icallid, ELIMIT, 0, 0);
76	* return;	76	* return;
77	* }	77	* }
78	* ipc_answer_fast(icallid, 0, 0, 0);	78	* ipc_answer_fast(icallid, 0, 0, 0);
79	*	79	*
80	* callid = async_get_call(&call);	80	* callid = async_get_call(&call);
81	* handle(callid, call);	81	* handle(callid, call);
82	* ipc_answer_fast(callid, 1,2,3);	82	* ipc_answer_fast(callid, 1,2,3);
83	*	83	*
84	* callid = async_get_call(&call);	84	* callid = async_get_call(&call);
85	* ....	85	* ....
86	* }	86	* }
87	*	87	*
88	* TODO: Detaching/joining dead psthreads?	88	* TODO: Detaching/joining dead psthreads?
89	*/	89	*/
90	#include <futex.h>	90	#include <futex.h>
91	#include <async.h>	91	#include <async.h>
92	#include <psthread.h>	92	#include <psthread.h>
93	#include <stdio.h>	93	#include <stdio.h>
94	#include <libadt/hash_table.h>	94	#include <libadt/hash_table.h>
95	#include <libadt/list.h>	95	#include <libadt/list.h>
96	#include <ipc/ipc.h>	96	#include <ipc/ipc.h>
97	#include <assert.h>	97	#include <assert.h>
98	#include <errno.h>	98	#include <errno.h>
99	#include <time.h>	99	#include <time.h>
100	#include <arch/barrier.h>	100	#include <arch/barrier.h>
101		101
102	atomic_t async_futex = FUTEX_INITIALIZER;	102	atomic_t async_futex = FUTEX_INITIALIZER;
103	static hash_table_t conn_hash_table;	103	static hash_table_t conn_hash_table;
104	static LIST_INITIALIZE(timeout_list);	104	static LIST_INITIALIZE(timeout_list);
105		105
106	typedef struct {	106	typedef struct {
107	struct timeval expires; /*< Expiration time for waiting thread /	107	struct timeval expires; /*< Expiration time for waiting thread /
108	int inlist; /*< If true, this struct is in timeout list /	108	int inlist; /*< If true, this struct is in timeout list /
109	link_t link;	109	link_t link;
110		110
111	pstid_t ptid; /*< Thread waiting for this message /	111	pstid_t ptid; /*< Thread waiting for this message /
112	int active; /*< If this thread is currently active /	112	int active; /*< If this thread is currently active /
113	int timedout; /*< If true, we timed out /	113	int timedout; /*< If true, we timed out /
114	} awaiter_t;	114	} awaiter_t;
115		115
116	typedef struct {	116	typedef struct {
117	awaiter_t wdata;	117	awaiter_t wdata;
118		118
119	int done; /*< If reply was received /	119	int done; /*< If reply was received /
120	ipc_call_t dataptr; /*< Pointer where the answer data	120	ipc_call_t dataptr; /*< Pointer where the answer data
121	* is stored */	121	* is stored */
122	ipcarg_t retval;	122	ipcarg_t retval;
123	} amsg_t;	123	} amsg_t;
124		124
125	typedef struct {	125	typedef struct {
126	link_t link;	126	link_t link;
127	ipc_callid_t callid;	127	ipc_callid_t callid;
128	ipc_call_t call;	128	ipc_call_t call;
129	} msg_t;	129	} msg_t;
130		130
131	typedef struct {	131	typedef struct {
132	awaiter_t wdata;	132	awaiter_t wdata;
133		133
134	link_t link; /*< Hash table link /	134	link_t link; /*< Hash table link /
135	ipcarg_t in_phone_hash; /*< Incoming phone hash. /	135	ipcarg_t in_phone_hash; /*< Incoming phone hash. /
136	link_t msg_queue; /*< Messages that should be delivered to this thread /	136	link_t msg_queue; /*< Messages that should be delivered to this thread /
137	/* Structures for connection opening packet */	137	/* Structures for connection opening packet */
138	ipc_callid_t callid;	138	ipc_callid_t callid;
139	ipc_call_t call;	139	ipc_call_t call;
140	ipc_callid_t close_callid; /* Identification of closing packet */	140	ipc_callid_t close_callid; /* Identification of closing packet */
141	void (cthread)(ipc_callid_t,ipc_call_t );	141	void (cthread)(ipc_callid_t,ipc_call_t );
142	} connection_t;	142	} connection_t;
143		143
144	/** Identifier of incoming connection handled by current thread */	144	/** Identifier of incoming connection handled by current thread */
145	__thread connection_t *PS_connection;	145	__thread connection_t *PS_connection;
146	/** If true, it is forbidden to use async_req functions and	146	/** If true, it is forbidden to use async_req functions and
147	* all preemption is disabled */	147	* all preemption is disabled */
148	__thread int in_interrupt_handler;	148	__thread int in_interrupt_handler;
149		149
150	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);	150	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call);
151	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);	151	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call);
152	static async_client_conn_t client_connection = default_client_connection;	152	static async_client_conn_t client_connection = default_client_connection;
153	static async_client_conn_t interrupt_received = default_interrupt_received;	153	static async_client_conn_t interrupt_received = default_interrupt_received;
154		154
155	/** Add microseconds to give timeval */	155	/** Add microseconds to give timeval */
156	static void tv_add(struct timeval *tv, suseconds_t usecs)	156	static void tv_add(struct timeval *tv, suseconds_t usecs)
157	{	157	{
158	tv->tv_sec += usecs / 1000000;	158	tv->tv_sec += usecs / 1000000;
159	tv->tv_usec += usecs % 1000000;	159	tv->tv_usec += usecs % 1000000;
160	if (tv->tv_usec > 1000000) {	160	if (tv->tv_usec > 1000000) {
161	tv->tv_sec++;	161	tv->tv_sec++;
162	tv->tv_usec -= 1000000;	162	tv->tv_usec -= 1000000;
163	}	163	}
164	}	164	}
165		165
166	/** Subtract 2 timevals, return microseconds difference */	166	/** Subtract 2 timevals, return microseconds difference */
167	static suseconds_t tv_sub(struct timeval tv1, struct timeval tv2)	167	static suseconds_t tv_sub(struct timeval tv1, struct timeval tv2)
168	{	168	{
169	suseconds_t result;	169	suseconds_t result;
170		170
171	result = tv1->tv_usec - tv2->tv_usec;	171	result = tv1->tv_usec - tv2->tv_usec;
172	result += (tv1->tv_sec - tv2->tv_sec) * 1000000;	172	result += (tv1->tv_sec - tv2->tv_sec) * 1000000;
173		173
174	return result;	174	return result;
175	}	175	}
176		176
177	/** Compare timeval	177	/** Compare timeval
178	*	178	*
179	* @return 1 if tv1 > tv2, otherwise 0	179	* @return 1 if tv1 > tv2, otherwise 0
180	*/	180	*/
181	static int tv_gt(struct timeval tv1, struct timeval tv2)	181	static int tv_gt(struct timeval tv1, struct timeval tv2)
182	{	182	{
183	if (tv1->tv_sec > tv2->tv_sec)	183	if (tv1->tv_sec > tv2->tv_sec)
184	return 1;	184	return 1;
185	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)	185	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec > tv2->tv_usec)
186	return 1;	186	return 1;
187	return 0;	187	return 0;
188	}	188	}
189	static int tv_gteq(struct timeval tv1, struct timeval tv2)	189	static int tv_gteq(struct timeval tv1, struct timeval tv2)
190	{	190	{
191	if (tv1->tv_sec > tv2->tv_sec)	191	if (tv1->tv_sec > tv2->tv_sec)
192	return 1;	192	return 1;
193	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)	193	if (tv1->tv_sec == tv2->tv_sec && tv1->tv_usec >= tv2->tv_usec)
194	return 1;	194	return 1;
195	return 0;	195	return 0;
196	}	196	}
197		197
198	/* Hash table functions */	198	/* Hash table functions */
199	#define CONN_HASH_TABLE_CHAINS 32	199	#define CONN_HASH_TABLE_CHAINS 32
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	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)	207	static int conn_compare(unsigned long key[], hash_count_t keys, link_t *item)
208	{	208	{
209	connection_t *hs;	209	connection_t *hs;
210		210
211	hs = hash_table_get_instance(item, connection_t, link);	211	hs = hash_table_get_instance(item, connection_t, link);
212		212
213	return key[0] == hs->in_phone_hash;	213	return key[0] == hs->in_phone_hash;
214	}	214	}
215		215
216	static void conn_remove(link_t *item)	216	static void conn_remove(link_t *item)
217	{	217	{
218	free(hash_table_get_instance(item, connection_t, link));	218	free(hash_table_get_instance(item, connection_t, link));
219	}	219	}
220		220
221		221
222	/** Operations for NS hash table. */	222	/** Operations for NS hash table. */
223	static hash_table_operations_t conn_hash_table_ops = {	223	static hash_table_operations_t conn_hash_table_ops = {
224	.hash = conn_hash,	224	.hash = conn_hash,
225	.compare = conn_compare,	225	.compare = conn_compare,
226	.remove_callback = conn_remove	226	.remove_callback = conn_remove
227	};	227	};
228		228
229	/** Insert sort timeout msg into timeouts list	229	/** Insert sort timeout msg into timeouts list
230	*	230	*
231	*/	231	*/
232	static void insert_timeout(awaiter_t *wd)	232	static void insert_timeout(awaiter_t *wd)
233	{	233	{
234	link_t *tmp;	234	link_t *tmp;
235	awaiter_t *cur;	235	awaiter_t *cur;
236		236
237	wd->timedout = 0;	237	wd->timedout = 0;
238	wd->inlist = 1;	238	wd->inlist = 1;
239		239
240	tmp = timeout_list.next;	240	tmp = timeout_list.next;
241	while (tmp != &timeout_list) {	241	while (tmp != &timeout_list) {
242	cur = list_get_instance(tmp, awaiter_t, link);	242	cur = list_get_instance(tmp, awaiter_t, link);
243	if (tv_gteq(&cur->expires, &wd->expires))	243	if (tv_gteq(&cur->expires, &wd->expires))
244	break;	244	break;
245	tmp = tmp->next;	245	tmp = tmp->next;
246	}	246	}
247	list_append(&wd->link, tmp);	247	list_append(&wd->link, tmp);
248	}	248	}
249		249
250	/*************************************************/	250	/*************************************************/
251		251
252	/** Try to route a call to an appropriate connection thread	252	/** Try to route a call to an appropriate connection thread
253	*	253	*
254	*/	254	*/
255	static int route_call(ipc_callid_t callid, ipc_call_t *call)	255	static int route_call(ipc_callid_t callid, ipc_call_t *call)
256	{	256	{
257	connection_t *conn;	257	connection_t *conn;
258	msg_t *msg;	258	msg_t *msg;
259	link_t *hlp;	259	link_t *hlp;
260	unsigned long key;	260	unsigned long key;
261		261
262	futex_down(&async_futex);	262	futex_down(&async_futex);
263		263
264	key = call->in_phone_hash;	264	key = call->in_phone_hash;
265	hlp = hash_table_find(&conn_hash_table, &key);	265	hlp = hash_table_find(&conn_hash_table, &key);
266	if (!hlp) {	266	if (!hlp) {
267	futex_up(&async_futex);	267	futex_up(&async_futex);
268	return 0;	268	return 0;
269	}	269	}
270	conn = hash_table_get_instance(hlp, connection_t, link);	270	conn = hash_table_get_instance(hlp, connection_t, link);
271		271
272	msg = malloc(sizeof(*msg));	272	msg = malloc(sizeof(*msg));
273	msg->callid = callid;	273	msg->callid = callid;
274	msg->call = *call;	274	msg->call = *call;
275	list_append(&msg->link, &conn->msg_queue);	275	list_append(&msg->link, &conn->msg_queue);
276		276
277	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)	277	if (IPC_GET_METHOD(*call) == IPC_M_PHONE_HUNGUP)
278	conn->close_callid = callid;	278	conn->close_callid = callid;
279		279
280	/* If the call is waiting for event, run it */	280	/* If the call is waiting for event, run it */
281	if (!conn->wdata.active) {	281	if (!conn->wdata.active) {
282	/* If in timeout list, remove it */	282	/* If in timeout list, remove it */
283	if (conn->wdata.inlist) {	283	if (conn->wdata.inlist) {
284	conn->wdata.inlist = 0;	284	conn->wdata.inlist = 0;
285	list_remove(&conn->wdata.link);	285	list_remove(&conn->wdata.link);
286	}	286	}
287	conn->wdata.active = 1;	287	conn->wdata.active = 1;
288	psthread_add_ready(conn->wdata.ptid);	288	psthread_add_ready(conn->wdata.ptid);
289	}	289	}
290		290
291	futex_up(&async_futex);	291	futex_up(&async_futex);
292		292
293	return 1;	293	return 1;
294	}	294	}
295		295
296	/** Return new incoming message for current(thread-local) connection */	296	/** Return new incoming message for current(thread-local) connection */
297	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)	297	ipc_callid_t async_get_call_timeout(ipc_call_t *call, suseconds_t usecs)
298	{	298	{
299	msg_t *msg;	299	msg_t *msg;
300	ipc_callid_t callid;	300	ipc_callid_t callid;
301	connection_t *conn;	301	connection_t *conn;
302		302
303	assert(PS_connection);	303	assert(PS_connection);
304	/* GCC 4.1.0 coughs on PS_connection-> dereference,	304	/* GCC 4.1.0 coughs on PS_connection-> dereference,
305	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.	305	* GCC 4.1.1 happilly puts the rdhwr instruction in delay slot.
306	* I would never expect to find so many errors in	306	* I would never expect to find so many errors in
307	* compiler ($&$(&$	307	* compiler ($&$(&$
308	*/	308	*/
309	conn = PS_connection;	309	conn = PS_connection;
310		310
311	futex_down(&async_futex);	311	futex_down(&async_futex);
312		312
313	if (usecs) {	313	if (usecs) {
314	gettimeofday(&conn->wdata.expires, NULL);	314	gettimeofday(&conn->wdata.expires, NULL);
315	tv_add(&conn->wdata.expires, usecs);	315	tv_add(&conn->wdata.expires, usecs);
316	} else {	316	} else {
317	conn->wdata.inlist = 0;	317	conn->wdata.inlist = 0;
318	}	318	}
319	/* If nothing in queue, wait until something appears */	319	/* If nothing in queue, wait until something appears */
320	while (list_empty(&conn->msg_queue)) {	320	while (list_empty(&conn->msg_queue)) {
321	if (usecs)	321	if (usecs)
322	insert_timeout(&conn->wdata);	322	insert_timeout(&conn->wdata);
323		323
324	conn->wdata.active = 0;	324	conn->wdata.active = 0;
325	psthread_schedule_next_adv(PS_TO_MANAGER);	325	psthread_schedule_next_adv(PS_TO_MANAGER);
326	/* Futex is up after getting back from async_manager	326	/* Futex is up after getting back from async_manager
327	* get it again */	327	* get it again */
328	futex_down(&async_futex);	328	futex_down(&async_futex);
329	if (usecs && conn->wdata.timedout && \	329	if (usecs && conn->wdata.timedout && \
330	list_empty(&conn->msg_queue)) {	330	list_empty(&conn->msg_queue)) {
331	/* If we timed out-> exit */	331	/* If we timed out-> exit */
332	futex_up(&async_futex);	332	futex_up(&async_futex);
333	return 0;	333	return 0;
334	}	334	}
335	}	335	}
336		336
337	msg = list_get_instance(conn->msg_queue.next, msg_t, link);	337	msg = list_get_instance(conn->msg_queue.next, msg_t, link);
338	list_remove(&msg->link);	338	list_remove(&msg->link);
339	callid = msg->callid;	339	callid = msg->callid;
340	*call = msg->call;	340	*call = msg->call;
341	free(msg);	341	free(msg);
342		342
343	futex_up(&async_futex);	343	futex_up(&async_futex);
344	return callid;	344	return callid;
345	}	345	}
346		346
347	/** Thread function that gets created on new connection	347	/** Thread function that gets created on new connection
348	*	348	*
349	* This function is defined as a weak symbol - to be redefined in	349	* This function is defined as a weak symbol - to be redefined in
350	* user code.	350	* user code.
351	*/	351	*/
352	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)	352	static void default_client_connection(ipc_callid_t callid, ipc_call_t *call)
353	{	353	{
354	ipc_answer_fast(callid, ENOENT, 0, 0);	354	ipc_answer_fast(callid, ENOENT, 0, 0);
355	}	355	}
356	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)	356	static void default_interrupt_received(ipc_callid_t callid, ipc_call_t *call)
357	{	357	{
358	}	358	}
359		359
360	/** Wrapper for client connection thread	360	/** Wrapper for client connection thread
361	*	361	*
362	* When new connection arrives, thread with this function is created.	362	* When new connection arrives, thread with this function is created.
363	* It calls client_connection and does final cleanup.	363	* It calls client_connection and does final cleanup.
364	*	364	*
365	* @param arg Connection structure pointer	365	* @param arg Connection structure pointer
366	*/	366	*/
367	static int connection_thread(void *arg)	367	static int connection_thread(void *arg)
368	{	368	{
369	unsigned long key;	369	unsigned long key;
370	msg_t *msg;	370	msg_t *msg;
371	int close_answered = 0;	371	int close_answered = 0;
372		372
373	/* Setup thread local connection pointer */	373	/* Setup thread local connection pointer */
374	PS_connection = (connection_t *)arg;	374	PS_connection = (connection_t *)arg;
375	PS_connection->cthread(PS_connection->callid, &PS_connection->call);	375	PS_connection->cthread(PS_connection->callid, &PS_connection->call);
376	/* Remove myself from connection hash table */	376	/* Remove myself from connection hash table */
377	futex_down(&async_futex);	377	futex_down(&async_futex);
378	key = PS_connection->in_phone_hash;	378	key = PS_connection->in_phone_hash;
379	hash_table_remove(&conn_hash_table, &key, 1);	379	hash_table_remove(&conn_hash_table, &key, 1);
380	futex_up(&async_futex);	380	futex_up(&async_futex);
381	/* Answer all remaining messages with ehangup */	381	/* Answer all remaining messages with ehangup */
382	while (!list_empty(&PS_connection->msg_queue)) {	382	while (!list_empty(&PS_connection->msg_queue)) {
383	msg = list_get_instance(PS_connection->msg_queue.next, msg_t, link);	383	msg = list_get_instance(PS_connection->msg_queue.next, msg_t, link);
384	list_remove(&msg->link);	384	list_remove(&msg->link);
385	if (msg->callid == PS_connection->close_callid)	385	if (msg->callid == PS_connection->close_callid)
386	close_answered = 1;	386	close_answered = 1;
387	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);	387	ipc_answer_fast(msg->callid, EHANGUP, 0, 0);
388	free(msg);	388	free(msg);
389	}	389	}
390	if (PS_connection->close_callid)	390	if (PS_connection->close_callid)
391	ipc_answer_fast(PS_connection->close_callid, 0, 0, 0);	391	ipc_answer_fast(PS_connection->close_callid, 0, 0, 0);
392	}	392	}
393		393
394	/** Create new thread for a new connection	394	/** Create new thread for a new connection
395	*	395	*
396	* Creates new thread for connection, fills in connection	396	* Creates new thread for connection, fills in connection
397	* structures and inserts it into the hash table, so that	397	* structures and inserts it into the hash table, so that
398	* later we can easily do routing of messages to particular	398	* later we can easily do routing of messages to particular
399	* threads.	399	* threads.
400	*	400	*
401	* @param in_phone_hash Identification of the incoming connection	401	* @param in_phone_hash Identification of the incoming connection
402	* @param callid Callid of the IPC_M_CONNECT_ME_TO packet	402	* @param callid Callid of the IPC_M_CONNECT_ME_TO packet
403	* @param call Call data of the opening packet	403	* @param call Call data of the opening packet
404	* @param cthread Thread function that should be called upon	404	* @param cthread Thread function that should be called upon
405	* opening the connection	405	* opening the connection
406	* @return New thread id	406	* @return New thread id
407	*/	407	*/
408	pstid_t async_new_connection(ipcarg_t in_phone_hash,ipc_callid_t callid,	408	pstid_t async_new_connection(ipcarg_t in_phone_hash,ipc_callid_t callid,
409	ipc_call_t *call,	409	ipc_call_t *call,
410	void (cthread)(ipc_callid_t,ipc_call_t ))	410	void (cthread)(ipc_callid_t,ipc_call_t ))
411	{	411	{
412	pstid_t ptid;	412	pstid_t ptid;
413	connection_t *conn;	413	connection_t *conn;
414	unsigned long key;	414	unsigned long key;
415		415
416	conn = malloc(sizeof(*conn));	416	conn = malloc(sizeof(*conn));
417	if (!conn) {	417	if (!conn) {
418	ipc_answer_fast(callid, ENOMEM, 0, 0);	418	ipc_answer_fast(callid, ENOMEM, 0, 0);
419	return NULL;	419	return NULL;
420	}	420	}
421	conn->in_phone_hash = in_phone_hash;	421	conn->in_phone_hash = in_phone_hash;
422	list_initialize(&conn->msg_queue);	422	list_initialize(&conn->msg_queue);
423	conn->callid = callid;	423	conn->callid = callid;
424	conn->close_callid = 0;	424	conn->close_callid = 0;
425	if (call)	425	if (call)
426	conn->call = *call;	426	conn->call = *call;
427	conn->wdata.active = 1; /* We will activate it asap */	427	conn->wdata.active = 1; /* We will activate it asap */
428	conn->cthread = cthread;	428	conn->cthread = cthread;
429		429
430	conn->wdata.ptid = psthread_create(connection_thread, conn);	430	conn->wdata.ptid = psthread_create(connection_thread, conn);
431	if (!conn->wdata.ptid) {	431	if (!conn->wdata.ptid) {
432	free(conn);	432	free(conn);
433	ipc_answer_fast(callid, ENOMEM, 0, 0);	433	ipc_answer_fast(callid, ENOMEM, 0, 0);
434	return NULL;	434	return NULL;
435	}	435	}
436	/* Add connection to hash table */	436	/* Add connection to hash table */
437	key = conn->in_phone_hash;	437	key = conn->in_phone_hash;
438	futex_down(&async_futex);	438	futex_down(&async_futex);
439	hash_table_insert(&conn_hash_table, &key, &conn->link);	439	hash_table_insert(&conn_hash_table, &key, &conn->link);
440	futex_up(&async_futex);	440	futex_up(&async_futex);
441		441
442	psthread_add_ready(conn->wdata.ptid);	442	psthread_add_ready(conn->wdata.ptid);
443		443
444	return conn->wdata.ptid;	444	return conn->wdata.ptid;
445	}	445	}
446		446
447	/** Handle call that was received */	447	/** Handle call that was received */
448	static void handle_call(ipc_callid_t callid, ipc_call_t *call)	448	static void handle_call(ipc_callid_t callid, ipc_call_t *call)
449	{	449	{
450	/* Unrouted call - do some default behaviour */	450	/* Unrouted call - do some default behaviour */
451	if ((callid & IPC_CALLID_NOTIFICATION)) {	451	if ((callid & IPC_CALLID_NOTIFICATION)) {
452	in_interrupt_handler = 1;	452	in_interrupt_handler = 1;
453	(*interrupt_received)(callid,call);	453	(*interrupt_received)(callid,call);
454	in_interrupt_handler = 0;	454	in_interrupt_handler = 0;
455	return;	455	return;
456	}	456	}
457		457
458	switch (IPC_GET_METHOD(*call)) {	458	switch (IPC_GET_METHOD(*call)) {
459	case IPC_M_CONNECT_ME_TO:	459	case IPC_M_CONNECT_ME_TO:
460	/* Open new connection with thread etc. */	460	/* Open new connection with thread etc. */
461	async_new_connection(IPC_GET_ARG3(*call), callid, call, client_connection);	461	async_new_connection(IPC_GET_ARG3(*call), callid, call, client_connection);
462	return;	462	return;
463	}	463	}
464		464
465	/* Try to route call through connection tables */	465	/* Try to route call through connection tables */
466	if (route_call(callid, call))	466	if (route_call(callid, call))
467	return;	467	return;
468		468
469	/* Unknown call from unknown phone - hang it up */	469	/* Unknown call from unknown phone - hang it up */
470	ipc_answer_fast(callid, EHANGUP, 0, 0);	470	ipc_answer_fast(callid, EHANGUP, 0, 0);
471	}	471	}
472		472
473	/** Fire all timeouts that expired	473	/** Fire all timeouts that expired
474	*	474	*
475	*/	475	*/
476	static void handle_expired_timeouts(void)	476	static void handle_expired_timeouts(void)
477	{	477	{
478	struct timeval tv;	478	struct timeval tv;
479	awaiter_t *waiter;	479	awaiter_t *waiter;
480	link_t *cur;	480	link_t *cur;
481		481
482	gettimeofday(&tv,NULL);	482	gettimeofday(&tv,NULL);
483	futex_down(&async_futex);	483	futex_down(&async_futex);
484		484
485	cur = timeout_list.next;	485	cur = timeout_list.next;
486	while (cur != &timeout_list) {	486	while (cur != &timeout_list) {
487	waiter = list_get_instance(cur,awaiter_t,link);	487	waiter = list_get_instance(cur,awaiter_t,link);
488	if (tv_gt(&waiter->expires, &tv))	488	if (tv_gt(&waiter->expires, &tv))
489	break;	489	break;
490	cur = cur->next;	490	cur = cur->next;
491	list_remove(&waiter->link);	491	list_remove(&waiter->link);
492	waiter->inlist = 0;	492	waiter->inlist = 0;
493	waiter->timedout = 1;	493	waiter->timedout = 1;
494	/* Redundant condition? The thread should not	494	/* Redundant condition? The thread should not
495	* be active when it gets here.	495	* be active when it gets here.
496	*/	496	*/
497	if (!waiter->active) {	497	if (!waiter->active) {
498	waiter->active = 1;	498	waiter->active = 1;
499	psthread_add_ready(waiter->ptid);	499	psthread_add_ready(waiter->ptid);
500	}	500	}

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(root)/tags/0.2.0.1/uspace/libc/generic/async.c – Rev 1965 → 1968