WebSVN – HelenOS – Diff – /trunk/uspace/lib/libc/generic/ipc.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
 * @{
 * @}
 */
 
/** @addtogroup libcipc IPC
 * @brief HelenOS uspace IPC
 * @{
 * @ingroup libc
 */
/** @file
 */
 
#include <ipc/ipc.h>
#include <libc.h>
#include <malloc.h>
#include <errno.h>
#include <libadt/list.h>
#include <stdio.h>
#include <unistd.h>
#include <futex.h>
#include <kernel/synch/synch.h>
#include <async.h>
#include <fibril.h>
#include <assert.h>
 
/**
 * Structures of this type are used for keeping track of sent asynchronous calls
 * and queing unsent calls.
 */
typedef struct {
    link_t list;
 
    ipc_async_callback_t callback;
    void *private;
    union {
        ipc_callid_t callid;
        struct {
            ipc_call_t data;
            int phoneid;
        } msg;
    } u;
    fid_t fid;  /**< Fibril waiting for sending this call. */
} async_call_t;
 
LIST_INITIALIZE(dispatched_calls);
 
/** List of asynchronous calls that were not accepted by kernel.
 *
 * It is protected by async_futex, because if the call cannot be sent into the
 * kernel, the async framework is used automatically.
 */
LIST_INITIALIZE(queued_calls);
 
static atomic_t ipc_futex = FUTEX_INITIALIZER;
 
/** Make a fast synchronous call.
 *
 * Only three payload arguments can be passed using this function. However, this
 * function is faster than the generic ipc_call_sync_slow() because the payload
 * is passed directly in registers.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param result1   If non-NULL, the return ARG1 will be stored there.
 * @param result2   If non-NULL, the return ARG2 will be stored there.
 * @param result3   If non-NULL, the return ARG3 will be stored there.
 * @param result4   If non-NULL, the return ARG4 will be stored there.
 * @param result5   If non-NULL, the return ARG5 will be stored there.
 *
 * @return      Negative values represent errors returned by IPC.
 *          Otherwise the RETVAL of the answer is returned.
 */
int
ipc_call_sync_fast(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
    ipcarg_t arg3, ipcarg_t *result1, ipcarg_t *result2, ipcarg_t *result3,
    ipcarg_t *result4, ipcarg_t *result5)
{
    ipc_call_t resdata;
    int callres;
   
    callres = __SYSCALL6(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,
        arg2, arg3, (sysarg_t) &resdata);
    if (callres)
        return callres;
    if (result1)
        *result1 = IPC_GET_ARG1(resdata);
    if (result2)
        *result2 = IPC_GET_ARG2(resdata);
    if (result3)
        *result3 = IPC_GET_ARG3(resdata);
    if (result4)
        *result4 = IPC_GET_ARG4(resdata);
    if (result5)
        *result5 = IPC_GET_ARG5(resdata);
 
    return IPC_GET_RETVAL(resdata);
}
 
/** Make a synchronous call transmitting 5 arguments of payload.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param arg4      Service-defined payload argument.
 * @param arg5      Service-defined payload argument.
 * @param result1   If non-NULL, storage for the first return argument.
 * @param result2   If non-NULL, storage for the second return argument.
 * @param result3   If non-NULL, storage for the third return argument.
 * @param result4   If non-NULL, storage for the fourth return argument.
 * @param result5   If non-NULL, storage for the fifth return argument.
 *
 * @return      Negative value means IPC error.
 *          Otherwise the RETVAL of the answer.
 */
int
ipc_call_sync_slow(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
    ipcarg_t arg3, ipcarg_t arg4, ipcarg_t arg5, ipcarg_t *result1,
    ipcarg_t *result2, ipcarg_t *result3, ipcarg_t *result4, ipcarg_t *result5)
{
    ipc_call_t data;
    int callres;
 
    IPC_SET_METHOD(data, method);
    IPC_SET_ARG1(data, arg1);
    IPC_SET_ARG2(data, arg2);
    IPC_SET_ARG3(data, arg3);
    IPC_SET_ARG4(data, arg4);
    IPC_SET_ARG5(data, arg5);
 
    callres = __SYSCALL3(SYS_IPC_CALL_SYNC_SLOW, phoneid, (sysarg_t) &data,
        (sysarg_t) &data);
    if (callres)
        return callres;
 
    if (result1)
        *result1 = IPC_GET_ARG1(data);
    if (result2)
        *result2 = IPC_GET_ARG2(data);
    if (result3)
        *result3 = IPC_GET_ARG3(data);
    if (result4)
        *result4 = IPC_GET_ARG4(data);
    if (result5)
        *result5 = IPC_GET_ARG5(data);
 
    return IPC_GET_RETVAL(data);
}
 
/** Syscall to send asynchronous message.
 *
 * @param phoneid   Phone handle for the call.
 * @param data      Call data with the request.
 *
 * @return      Hash of the call or an error code.
 */
static ipc_callid_t _ipc_call_async(int phoneid, ipc_call_t *data)
{
    return __SYSCALL2(SYS_IPC_CALL_ASYNC_SLOW, phoneid, (sysarg_t) data);
}
 
/** Prolog to ipc_call_async_*() functions.
 *
 * @param private   Argument for the answer/error callback.
 * @param callback  Answer/error callback.
 *
 * @return      New, partially initialized async_call structure or NULL.
 */
static inline async_call_t *ipc_prepare_async(void *private,
    ipc_async_callback_t callback)
{
    async_call_t *call;
 
    call = malloc(sizeof(*call));
    if (!call) {
        if (callback)
            callback(private, ENOMEM, NULL);
        return NULL;
    }
    call->callback = callback;
    call->private = private;
 
    return call;
}
 
/** Epilogue of ipc_call_async_*() functions.
 *
 * @param callid    Value returned by the SYS_IPC_CALL_ASYNC_* syscall.
 * @param phoneid   Phone handle through which the call was made.
 * @param call      async_call structure returned by ipc_prepare_async().
 * @param can_preempt   If non-zero, the current fibril can be preempted in this
 *          call.
 */
static inline void ipc_finish_async(ipc_callid_t callid, int phoneid,
    async_call_t *call, int can_preempt)
{
    if (!call) { /* Nothing to do regardless if failed or not */
        futex_up(&ipc_futex);
        return;
    }
 
    if (callid == IPC_CALLRET_FATAL) {
        futex_up(&ipc_futex);
        /* Call asynchronous handler with error code */
        if (call->callback)
            call->callback(call->private, ENOENT, NULL);
        free(call);
        return;
    }
 
    if (callid == IPC_CALLRET_TEMPORARY) {
        futex_up(&ipc_futex);
 
        call->u.msg.phoneid = phoneid;
       
        futex_down(&async_futex);
        list_append(&call->list, &queued_calls);
 
        if (can_preempt) {
            call->fid = fibril_get_id();
            fibril_switch(FIBRIL_TO_MANAGER);
            /* Async futex unlocked by previous call */
        } else {
            call->fid = 0;
            futex_up(&async_futex);
        }
        return;
    }
    call->u.callid = callid;
    /* Add call to the list of dispatched calls */
    list_append(&call->list, &dispatched_calls);
    futex_up(&ipc_futex);
   
}
 
/** Make a fast asynchronous call.
 *
 * This function can only handle four arguments of payload. It is, however,
 * faster than the more generic ipc_call_async_slow().
 *
 * Note that this function is a void function.
 * During normal opertation, answering this call will trigger the callback.
 * In case of fatal error, call the callback handler with the proper error code.
 * If the call cannot be temporarily made, queue it.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param arg4      Service-defined payload argument.
 * @param private   Argument to be passed to the answer/error callback.
 * @param callback  Answer or error callback.
 * @param can_preempt   If non-zero, the current fibril will be preempted in
 *          case the kernel temporarily refuses to accept more
 *          asynchronous calls.
 */
void ipc_call_async_fast(int phoneid, ipcarg_t method, ipcarg_t arg1,
    ipcarg_t arg2, ipcarg_t arg3, ipcarg_t arg4, void *private,
    ipc_async_callback_t callback, int can_preempt)
{
    async_call_t *call = NULL;
    ipc_callid_t callid;
 
    if (callback) {
        call = ipc_prepare_async(private, callback);
        if (!call)
            return;
    }
 
    /*
     * We need to make sure that we get callid before another thread
     * accesses the queue again.
     */
    futex_down(&ipc_futex);
    callid = __SYSCALL6(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1,
        arg2, arg3, arg4);
 
    if (callid == IPC_CALLRET_TEMPORARY) {
        if (!call) {
            call = ipc_prepare_async(private, callback);
            if (!call)
                return;
        }
        IPC_SET_METHOD(call->u.msg.data, method);
        IPC_SET_ARG1(call->u.msg.data, arg1);
        IPC_SET_ARG2(call->u.msg.data, arg2);
        IPC_SET_ARG3(call->u.msg.data, arg3);
        IPC_SET_ARG4(call->u.msg.data, arg4);
        /*
         * To achieve deterministic behavior, we always zero out the
         * arguments that are beyond the limits of the fast version.
         */
        IPC_SET_ARG5(call->u.msg.data, 0);
    }
    ipc_finish_async(callid, phoneid, call, can_preempt);
}
 
/** Make an asynchronous call transmitting the entire payload.
 *
 * Note that this function is a void function.
 * During normal opertation, answering this call will trigger the callback.
 * In case of fatal error, call the callback handler with the proper error code.
 * If the call cannot be temporarily made, queue it.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param arg4      Service-defined payload argument.
 * @param arg5      Service-defined payload argument.
 * @param private   Argument to be passed to the answer/error callback.
 * @param callback  Answer or error callback.
 * @param can_preempt   If non-zero, the current fibril will be preempted in
 *          case the kernel temporarily refuses to accept more
 *          asynchronous calls.
 *
 */
void ipc_call_async_slow(int phoneid, ipcarg_t method, ipcarg_t arg1,
    ipcarg_t arg2, ipcarg_t arg3, ipcarg_t arg4, ipcarg_t arg5, void *private,
    ipc_async_callback_t callback, int can_preempt)
{
    async_call_t *call;
    ipc_callid_t callid;
 
    call = ipc_prepare_async(private, callback);
    if (!call)
        return;
 
    IPC_SET_METHOD(call->u.msg.data, method);
    IPC_SET_ARG1(call->u.msg.data, arg1);
    IPC_SET_ARG2(call->u.msg.data, arg2);
    IPC_SET_ARG3(call->u.msg.data, arg3);
    IPC_SET_ARG4(call->u.msg.data, arg4);
    IPC_SET_ARG5(call->u.msg.data, arg5);
    /*
     * We need to make sure that we get callid before another thread
     * accesses the queue again.
     */
    futex_down(&ipc_futex);
    callid = _ipc_call_async(phoneid, &call->u.msg.data);
 
    ipc_finish_async(callid, phoneid, call, can_preempt);
}
 
 
/** Answer a received call - fast version.
 *
 * The fast answer makes use of passing retval and first four arguments in
 * registers. If you need to return more, use the ipc_answer_slow() instead.
 *
 * @param callid    Hash of the call being answered.
 * @param retval    Return value.
 * @param arg1      First return argument.
 * @param arg2      Second return argument.
 * @param arg3      Third return argument.
 * @param arg4      Fourth return argument.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_answer_fast(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
    ipcarg_t arg2, ipcarg_t arg3, ipcarg_t arg4)
{
    return __SYSCALL6(SYS_IPC_ANSWER_FAST, callid, retval, arg1, arg2, arg3,
        arg4);
}
 
/** Answer a received call - slow full version.
 *
 * @param callid    Hash of the call being answered.
 * @param retval    Return value.
 * @param arg1      First return argument.
 * @param arg2      Second return argument.
 * @param arg3      Third return argument.
 * @param arg4      Fourth return argument.
 * @param arg5      Fifth return argument.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_answer_slow(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
    ipcarg_t arg2, ipcarg_t arg3, ipcarg_t arg4, ipcarg_t arg5)
{
    ipc_call_t data;
 
    IPC_SET_RETVAL(data, retval);
    IPC_SET_ARG1(data, arg1);
    IPC_SET_ARG2(data, arg2);
    IPC_SET_ARG3(data, arg3);
    IPC_SET_ARG4(data, arg4);
    IPC_SET_ARG5(data, arg5);
 
    return __SYSCALL2(SYS_IPC_ANSWER_SLOW, callid, (sysarg_t) &data);
}
 
 
/** Try to dispatch queued calls from the async queue. */
static void try_dispatch_queued_calls(void)
{
    async_call_t *call;
    ipc_callid_t callid;
 
    /** @todo
     * Integrate intelligently ipc_futex, so that it is locked during
     * ipc_call_async_*(), until it is added to dispatched_calls.
     */
    futex_down(&async_futex);
    while (!list_empty(&queued_calls)) {
        call = list_get_instance(queued_calls.next, async_call_t, list);
        callid = _ipc_call_async(call->u.msg.phoneid,
            &call->u.msg.data);
        if (callid == IPC_CALLRET_TEMPORARY) {
            break;
        }
        list_remove(&call->list);
 
        futex_up(&async_futex);
        if (call->fid)
            fibril_add_ready(call->fid);
       
        if (callid == IPC_CALLRET_FATAL) {
            if (call->callback)
                call->callback(call->private, ENOENT, NULL);
            free(call);
        } else {
            call->u.callid = callid;
            futex_down(&ipc_futex);
            list_append(&call->list, &dispatched_calls);
            futex_up(&ipc_futex);
        }
        futex_down(&async_futex);
    }
    futex_up(&async_futex);
}
 
/** Handle a received answer.
 *
 * Find the hash of the answer and call the answer callback.
 *
 * @todo Make it use hash table.
 *
 * @param callid    Hash of the received answer.
 *          The answer has the same hash as the request OR'ed with
 *          the IPC_CALLID_ANSWERED bit.
 * @param data      Call data of the answer.
 */
static void handle_answer(ipc_callid_t callid, ipc_call_t *data)
{
    link_t *item;
    async_call_t *call;
 
    callid &= ~IPC_CALLID_ANSWERED;
   
    futex_down(&ipc_futex);
    for (item = dispatched_calls.next; item != &dispatched_calls;
        item = item->next) {
        call = list_get_instance(item, async_call_t, list);
        if (call->u.callid == callid) {
            list_remove(&call->list);
            futex_up(&ipc_futex);
            if (call->callback)
                call->callback(call->private,
                    IPC_GET_RETVAL(*data), data);
            free(call);
            return;
        }
    }
    futex_up(&ipc_futex);
}
 
 
/** Wait for a first call to come.
 *
 * @param call      Storage where the incoming call data will be stored.
 * @param usec      Timeout in microseconds
 * @param flags     Flags passed to SYS_IPC_WAIT (blocking, nonblocking).
 *
 * @return      Hash of the call. Note that certain bits have special
 *          meaning. IPC_CALLID_ANSWERED will be set in an answer
 *          and IPC_CALLID_NOTIFICATION is used for notifications.
 *         
 */
ipc_callid_t ipc_wait_cycle(ipc_call_t *call, uint32_t usec, int flags)
{
    ipc_callid_t callid;
 
    callid = __SYSCALL3(SYS_IPC_WAIT, (sysarg_t) call, usec, flags);
    /* Handle received answers */
    if (callid & IPC_CALLID_ANSWERED) {
        handle_answer(callid, call);
        try_dispatch_queued_calls();
    }
 
    return callid;
}
 
/** Wait some time for an IPC call.
 *
 * The call will return after an answer is received.
 *
 * @param call      Storage where the incoming call data will be stored.
 * @param usec      Timeout in microseconds.
 *
 * @return      Hash of the answer.
 */
ipc_callid_t ipc_wait_for_call_timeout(ipc_call_t *call, uint32_t usec)
{
    ipc_callid_t callid;
 
    do {
        callid = ipc_wait_cycle(call, usec, SYNCH_FLAGS_NONE);
    } while (callid & IPC_CALLID_ANSWERED);
 
    return callid;
}
 
/** Check if there is an IPC call waiting to be picked up.
 *
 * @param call      Storage where the incoming call will be stored.
 * @return      Hash of the answer.
 */
ipc_callid_t ipc_trywait_for_call(ipc_call_t *call)
{
    ipc_callid_t callid;
 
    do {
        callid = ipc_wait_cycle(call, SYNCH_NO_TIMEOUT,
            SYNCH_FLAGS_NON_BLOCKING);
    } while (callid & IPC_CALLID_ANSWERED);
 
    return callid;
}
 
/** Ask destination to do a callback connection.
 *
 * @param phoneid   Phone handle used for contacting the other side.
 * @param arg1      Service-defined argument.
 * @param arg2      Service-defined argument.
 * @param phonehash Storage where the library will store an opaque
 *          identifier of the phone that will be used for incoming
 *          calls. This identifier can be used for connection
 *          tracking.
 *
 * @return      Zero on success or a negative error code.
 */
int ipc_connect_to_me(int phoneid, int arg1, int arg2, ipcarg_t *phonehash)
{
    return ipc_call_sync_2_3(phoneid, IPC_M_CONNECT_TO_ME, arg1, arg2,
        NULL, NULL, phonehash);
}
 
/** Ask through phone for a new connection to some service.
 *
 * @param phoneid   Phone handle used for contacting the other side.
 * @param arg1      User defined argument.
 * @param arg2      User defined argument.
 *
 * @return      New phone handle on success or a negative error code.
 */
int ipc_connect_me_to(int phoneid, int arg1, int arg2)
{
    ipcarg_t newphid;
    int res;
 
    res = ipc_call_sync_2_3(phoneid, IPC_M_CONNECT_ME_TO, arg1, arg2, NULL,
        NULL, &newphid);
    if (res)
        return res;
    return newphid;
}
 
/** Hang up a phone.
 *
 * @param phoneid   Handle of the phone to be hung up.
 *
 * @return      Zero on success or a negative error code.
 */
int ipc_hangup(int phoneid)
{
    return __SYSCALL1(SYS_IPC_HANGUP, phoneid);
}
 
/** Register IRQ notification.
 *
 * @param inr       IRQ number.
 * @param devno     Device number of the device generating inr.
 * @param method    Use this method for notifying me.
 * @param ucode     Top-half pseudocode handler.
 *
 * @return      Value returned by the kernel.
 */
int ipc_register_irq(int inr, int devno, int method, irq_code_t *ucode)
{
    return __SYSCALL4(SYS_IPC_REGISTER_IRQ, inr, devno, method,
        (sysarg_t) ucode);
}
 
/** Unregister IRQ notification.
 *
 * @param inr       IRQ number.
 * @param devno     Device number of the device generating inr.
 *
 * @return      Value returned by the kernel.
 */
int ipc_unregister_irq(int inr, int devno)
{
    return __SYSCALL2(SYS_IPC_UNREGISTER_IRQ, inr, devno);
}
 
/** Forward a received call to another destination.
 *
 * @param callid    Hash of the call to forward.
 * @param phoneid   Phone handle to use for forwarding.
 * @param method    New method for the forwarded call.
 * @param arg1      New value of the first argument for the forwarded call.
 *
 * @return      Zero on success or an error code.
 *
 * For non-system methods, the old method and arg1 are rewritten by the new
 * values. For system methods, the new method and arg1 are written to the old
 * arg1 and arg2, respectivelly. Calls with immutable methods are forwarded
 * verbatim.
 */
int ipc_forward_fast(ipc_callid_t callid, int phoneid, int method,
    ipcarg_t arg1)
{
    return __SYSCALL4(SYS_IPC_FORWARD_FAST, callid, phoneid, method, arg1);
}
 
/** Wrapper for making IPC_M_DATA_SEND calls.
 *
 * @param phoneid   Phone that will be used to contact the receiving side.
 * @param src       Address of the beginning of the source buffer.
 * @param size      Size of the source buffer.
 *
 * @return      Zero on success or a negative error code from errno.h.
 */
int ipc_data_send(int phoneid, void *src, size_t size)
{
    return ipc_call_sync_3_0(phoneid, IPC_M_DATA_SEND, 0, (ipcarg_t) src,
        (ipcarg_t) size);
}
 
/** Wrapper for receiving the IPC_M_DATA_SEND calls.
 *
 * This wrapper only makes it more comfortable to receive IPC_M_DATA_SEND calls
 * so that the user doesn't have to remember the meaning of each IPC argument.
 *
 * So far, this wrapper is to be used from within a connection fibril.
 *
 * @param callid    Storage where the hash of the IPC_M_DATA_SEND call will
 *          be stored.
 * @param dst       Storage where the suggested destination address will
 *          be stored. May be NULL.
 * @param size      Storage where the suggested size will be stored. May be
 *          NULL
 *
 * @return      Non-zero on success, zero on failure.
 */
int ipc_data_receive(ipc_callid_t *callid, void **dst, size_t *size)
{
    ipc_call_t data;
   
    assert(callid);
 
    *callid = async_get_call(&data);
    if (IPC_GET_METHOD(data) != IPC_M_DATA_SEND)
        return 0;
    if (dst)
        *dst = (void *) IPC_GET_ARG1(data);
    if (size)
        *size = (size_t) IPC_GET_ARG3(data);
    return 1;
}
 
/** Wrapper for answering the IPC_M_DATA_SEND calls.
 *
 * This wrapper only makes it more comfortable to answer IPC_M_DATA_SEND calls
 * so that the user doesn't have to remember the meaning of each IPC argument.
 *
 * @param callid    Hash of the IPC_M_DATA_SEND call to answer.
 * @param dst       Final destination address for the IPC_M_DATA_SEND call.
 * @param size      Final size for the IPC_M_DATA_SEND call.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_data_deliver(ipc_callid_t callid, void *dst, size_t size)
{
    return ipc_answer_3(callid, EOK, (ipcarg_t) dst, 0, (ipcarg_t) size);
}
 
/** @}
 */
 
Subversion Repositories HelenOS

(root)/trunk/uspace/lib/libc/generic/ipc.c @ 2622 – Rev 2619 → 2620
