/*
* 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.
*/
#include <ipc.h>
#include <libc.h>
#include <malloc.h>
#include <errno.h>
#include <list.h>
#include <stdio.h>
#include <unistd.h>
/** Structure used for keeping track of sent async msgs
* and queing unsent msgs
*
*/
typedef struct {
link_t list;
ipc_async_callback_t callback;
void *private;
union {
ipc_callid_t callid;
struct {
int phoneid;
ipc_data_t data;
} msg;
}u;
} async_call_t;
LIST_INITIALIZE(dispatched_calls);
LIST_INITIALIZE(queued_calls);
int ipc_call_sync(int phoneid, ipcarg_t method, ipcarg_t arg1,
ipcarg_t *result)
{
ipc_data_t resdata;
int callres;
callres = __SYSCALL4(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,
(sysarg_t)&resdata);
if (callres)
return callres;
if (result)
*result = IPC_GET_ARG1(resdata);
return IPC_GET_RETVAL(resdata);
}
int ipc_call_sync_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
ipcarg_t arg2, ipcarg_t arg3,
ipcarg_t *result1, ipcarg_t *result2, ipcarg_t *result3)
{
ipc_data_t data;
int callres;
IPC_SET_METHOD(data, method);
IPC_SET_ARG1(data, arg1);
IPC_SET_ARG2(data, arg2);
IPC_SET_ARG3(data, arg3);
callres = __SYSCALL2(SYS_IPC_CALL_SYNC, phoneid, (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);
return IPC_GET_RETVAL(data);
}
/** Syscall to send asynchronous message */
static ipc_callid_t _ipc_call_async(int phoneid, ipc_data_t *data)
{
return __SYSCALL2(SYS_IPC_CALL_ASYNC, phoneid, (sysarg_t)data);
}
/** Send asynchronous message
*
* - if fatal error, call callback handler with proper error code
* - if message cannot be temporarily sent, add to queue
*/
void ipc_call_async_2(int phoneid, ipcarg_t method, ipcarg_t arg1,
ipcarg_t arg2, void *private,
ipc_async_callback_t callback)
{
async_call_t *call;
ipc_callid_t callid;
if (!call) {
callback(private, ENOMEM, NULL);
}
callid = __SYSCALL4(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1, arg2);
if (callid == IPC_CALLRET_FATAL) {
/* Call asynchronous handler with error code */
IPC_SET_RETVAL(call->u.msg.data, ENOENT);
callback(private, ENOENT, NULL);
return;
}
call->callback = callback;
call->private = private;
if (callid == IPC_CALLRET_TEMPORARY) {
/* Add asynchronous call to queue of non-dispatched async calls */
call->u.msg.phoneid = phoneid;
IPC_SET_METHOD(call->u.msg.data, method);
IPC_SET_ARG1(call->u.msg.data, arg1);
IPC_SET_ARG2(call->u.msg.data, arg2);
list_append(&call->list, &queued_calls);
return;
}
call->u.callid = callid;
/* Add call to list of dispatched calls */
list_append(&call->list, &dispatched_calls);
}
/** Send answer to a received call */
void ipc_answer(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
ipcarg_t arg2)
{
__SYSCALL4(SYS_IPC_ANSWER, callid, retval, arg1, arg2);
}
/** Call syscall function sys_ipc_wait_for_call */
static inline ipc_callid_t _ipc_wait_for_call(ipc_data_t *data, int flags)
{
return __SYSCALL2(SYS_IPC_WAIT, (sysarg_t)data, flags);
}
/** Try to dispatch queed calls from async queue */
static void try_dispatch_queued_calls(void)
{
async_call_t *call;
ipc_callid_t callid;
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);
if (callid == IPC_CALLRET_FATAL) {
call->callback(call->private, ENOENT, NULL);
} else {
call->u.callid = callid;
list_append(&call->list, &dispatched_calls);
}
}
}
/** Handle received answer
*
* TODO: Make it use hash table
*
* @param callid Callid (with first bit set) of the answered call
*/
static void handle_answer(ipc_callid_t callid, ipc_data_t *data)
{
link_t *item;
async_call_t *call;
callid &= ~IPC_CALLID_ANSWERED;
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);
call->callback(call->private,
IPC_GET_RETVAL(*data),
data);
return;
}
}
printf("Received unidentified answer: %P!!!\n", callid
); }
/** Wait for IPC call and return
*
* - dispatch ASYNC reoutines in the background
* @param data Space where the message is stored
* @return Callid or 0 if nothing available and started with
* IPC_WAIT_NONBLOCKING
*/
int ipc_wait_for_call(ipc_data_t *data, int flags)
{
ipc_callid_t callid;
do {
try_dispatch_queued_calls();
callid = _ipc_wait_for_call(data, flags);
/* Handle received answers */
if (callid & IPC_CALLID_ANSWERED)
handle_answer(callid, data);
} while (callid & IPC_CALLID_ANSWERED);
return callid;
}