/*
* 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 ns
* @{
*/
/**
* @file ns.c
* @brief Naming service for HelenOS IPC.
*/
#include <ipc/ipc.h>
#include <ipc/ns.h>
#include <ipc/services.h>
#include <stdio.h>
#include <bool.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <assert.h>
#include <libadt/list.h>
#include <libadt/hash_table.h>
#include <sysinfo.h>
#include <loader/loader.h>
#include <ddi.h>
#include <as.h>
#define NAME "ns"
#define NS_HASH_TABLE_CHAINS 20
static int register_service(ipcarg_t service, ipcarg_t phone, ipc_call_t *call);
static void connect_to_service(ipcarg_t service, ipc_call_t *call,
ipc_callid_t callid);
void register_clonable(ipcarg_t service, ipcarg_t phone, ipc_call_t *call,
ipc_callid_t callid);
void connect_to_clonable(ipcarg_t service, ipc_call_t *call,
ipc_callid_t callid);
/* Static functions implementing NS hash table operations. */
static hash_index_t ns_hash(unsigned long *key);
static int ns_compare(unsigned long *key, hash_count_t keys, link_t *item);
static void ns_remove(link_t *item);
/** Operations for NS hash table. */
static hash_table_operations_t ns_hash_table_ops = {
.hash = ns_hash,
.compare = ns_compare,
.remove_callback = ns_remove
};
/** NS hash table structure. */
static hash_table_t ns_hash_table;
/** NS hash table item. */
typedef struct {
link_t link;
ipcarg_t service; /**< Number of the service. */
ipcarg_t phone; /**< Phone registered with the service. */
ipcarg_t in_phone_hash; /**< Incoming phone hash. */
} hashed_service_t;
/** Pending connection structure. */
typedef struct {
link_t link;
ipcarg_t service; /**< Number of the service. */
ipc_callid_t callid; /**< Call ID waiting for the connection */
ipcarg_t arg2; /**< Second argument */
ipcarg_t arg3; /**< Third argument */
} pending_req_t;
static link_t pending_req;
/** Request for connection to a clonable service. */
typedef struct {
link_t link;
ipcarg_t service;
ipc_call_t call;
ipc_callid_t callid;
} cs_req_t;
/** List of clonable-service connection requests. */
static link_t cs_req;
static void *clockaddr = NULL;
static void *klogaddr = NULL;
/** Return true if @a service is clonable. */
static bool service_clonable(int service)
{
return (service == SERVICE_LOAD);
}
static void get_as_area(ipc_callid_t callid, ipc_call_t *call, char *name, void **addr)
{
void *ph_addr;
if (!*addr) {
ph_addr = (void *) sysinfo_value(name);
if (!ph_addr) {
ipc_answer_0(callid, ENOENT);
return;
}
*addr = as_get_mappable_page(PAGE_SIZE);
if (physmem_map(ph_addr, *addr, 1,
AS_AREA_READ | AS_AREA_CACHEABLE) != 0) {
ipc_answer_0(callid, ENOENT);
return;
}
}
ipc_answer_2(callid, EOK, (ipcarg_t) *addr, AS_AREA_READ);
}
/** Process pending connection requests */
static void process_pending_req()
{
link_t *cur;
loop:
for (cur = pending_req.next; cur != &pending_req; cur = cur->next) {
pending_req_t *pr = list_get_instance(cur, pending_req_t, link);
unsigned long keys[3] = {
pr->service,
0,
0
};
link_t *link = hash_table_find(&ns_hash_table, keys);
if (!link)
continue;
hashed_service_t *hs = hash_table_get_instance(link, hashed_service_t, link);
ipcarg_t retval = ipc_forward_fast(pr->callid, hs->phone,
pr->arg2, pr->arg3, 0, IPC_FF_NONE);
if (!(pr->callid & IPC_CALLID_NOTIFICATION))
ipc_answer_0(pr->callid, retval);
list_remove(cur);
goto loop;
}
}
int main(int argc, char **argv)
{
printf(NAME
": HelenOS IPC Naming Service\n");
if (!hash_table_create(&ns_hash_table, NS_HASH_TABLE_CHAINS, 3,
&ns_hash_table_ops)) {
printf(NAME
": No memory available for services\n"); return ENOMEM;
}
list_initialize(&pending_req);
list_initialize(&cs_req);
printf(NAME
": Accepting connections\n"); while (true) {
process_pending_req();
ipc_call_t call;
ipc_callid_t callid = ipc_wait_for_call(&call);
ipcarg_t retval;
switch (IPC_GET_METHOD(call)) {
case IPC_M_SHARE_IN:
switch (IPC_GET_ARG3(call)) {
case SERVICE_MEM_REALTIME:
get_as_area(callid, &call, "clock.faddr", &clockaddr);
break;
case SERVICE_MEM_KLOG:
get_as_area(callid, &call, "klog.faddr", &klogaddr);
break;
default:
ipc_answer_0(callid, ENOENT);
}
continue;
case IPC_M_PHONE_HUNGUP:
retval = EOK;
break;
case IPC_M_CONNECT_TO_ME:
/*
* Server requests service registration.
*/
if (service_clonable(IPC_GET_ARG1(call))) {
register_clonable(IPC_GET_ARG1(call),
IPC_GET_ARG5(call), &call, callid);
continue;
} else {
retval = register_service(IPC_GET_ARG1(call),
IPC_GET_ARG5(call), &call);
}
break;
case IPC_M_CONNECT_ME_TO:
/*
* Client requests to be connected to a service.
*/
if (service_clonable(IPC_GET_ARG1(call))) {
connect_to_clonable(IPC_GET_ARG1(call),
&call, callid);
continue;
} else {
connect_to_service(IPC_GET_ARG1(call), &call,
callid);
continue;
}
break;
default:
retval = ENOENT;
break;
}
if (!(callid & IPC_CALLID_NOTIFICATION))
ipc_answer_0(callid, retval);
}
/* Not reached */
return 0;
}
/** Register service.
*
* @param service Service to be registered.
* @param phone Phone to be used for connections to the service.
* @param call Pointer to call structure.
*
* @return Zero on success or a value from @ref errno.h.
*
*/
int register_service(ipcarg_t service, ipcarg_t phone, ipc_call_t *call)
{
unsigned long keys[3] = {
service,
call->in_phone_hash,
0
};
if (hash_table_find(&ns_hash_table, keys))
return EEXISTS;
hashed_service_t
*hs
= (hashed_service_t
*) malloc(sizeof(hashed_service_t
)); if (!hs)
return ENOMEM;
link_initialize(&hs->link);
hs->service = service;
hs->phone = phone;
hs->in_phone_hash = call->in_phone_hash;
hash_table_insert(&ns_hash_table, keys, &hs->link);
return 0;
}
/** Connect client to service.
*
* @param service Service to be connected to.
* @param call Pointer to call structure.
* @param callid Call ID of the request.
*
* @return Zero on success or a value from @ref errno.h.
*
*/
void connect_to_service(ipcarg_t service, ipc_call_t *call, ipc_callid_t callid)
{
ipcarg_t retval;
unsigned long keys[3] = {
service,
0,
0
};
link_t *link = hash_table_find(&ns_hash_table, keys);
if (!link) {
if (IPC_GET_ARG4(*call) & IPC_FLAG_BLOCKING) {
/* Blocking connection, add to pending list */
pending_req_t
*pr
= (pending_req_t
*) malloc(sizeof(pending_req_t
)); if (!pr) {
retval = ENOMEM;
goto out;
}
pr->service = service;
pr->callid = callid;
pr->arg2 = IPC_GET_ARG2(*call);
pr->arg3 = IPC_GET_ARG3(*call);
list_append(&pr->link, &pending_req);
return;
}
retval = ENOENT;
goto out;
}
hashed_service_t *hs = hash_table_get_instance(link, hashed_service_t, link);
retval = ipc_forward_fast(callid, hs->phone, IPC_GET_ARG2(*call),
IPC_GET_ARG3(*call), 0, IPC_FF_NONE);
out:
if (!(callid & IPC_CALLID_NOTIFICATION))
ipc_answer_0(callid, retval);
}
/** Register clonable service.
*
* @param service Service to be registered.
* @param phone Phone to be used for connections to the service.
* @param call Pointer to call structure.
*
*/
void register_clonable(ipcarg_t service, ipcarg_t phone, ipc_call_t *call,
ipc_callid_t callid)
{
if (list_empty(&cs_req)) {
/* There was no pending connection request. */
printf(NAME
": Unexpected clonable server.\n"); ipc_answer_0(callid, EBUSY);
return;
}
cs_req_t *csr = list_get_instance(cs_req.next, cs_req_t, link);
list_remove(&csr->link);
/* Currently we can only handle a single type of clonable service. */
assert(csr
->service
== SERVICE_LOAD
);
ipc_answer_0(callid, EOK);
int rc = ipc_forward_fast(csr->callid, phone, IPC_GET_ARG2(csr->call),
IPC_GET_ARG3(csr->call), 0, IPC_FF_NONE);
ipc_hangup(phone);
}
/** Connect client to clonable service.
*
* @param service Service to be connected to.
* @param call Pointer to call structure.
* @param callid Call ID of the request.
*
* @return Zero on success or a value from @ref errno.h.
*
*/
void connect_to_clonable(ipcarg_t service, ipc_call_t *call,
ipc_callid_t callid)
{
assert(service
== SERVICE_LOAD
);
cs_req_t
*csr
= malloc(sizeof(cs_req_t
)); if (csr == NULL) {
ipc_answer_0(callid, ENOMEM);
return;
}
/* Spawn a loader. */
int rc = loader_spawn("loader");
if (rc < 0) {
ipc_answer_0(callid, rc);
return;
}
csr->service = service;
csr->call = *call;
csr->callid = callid;
/*
* We can forward the call only after the server we spawned connects
* to us. Meanwhile we might need to service more connection requests.
* Thus we store the call in a queue.
*/
list_append(&csr->link, &cs_req);
}
/** Compute hash index into NS hash table.
*
* @param key Pointer keys. However, only the first key (i.e. service number)
* is used to compute the hash index.
*
* @return Hash index corresponding to key[0].
*
*/
hash_index_t ns_hash(unsigned long *key)
{
return (*key % NS_HASH_TABLE_CHAINS);
}
/** Compare a key with hashed item.
*
* This compare function always ignores the third key.
* It exists only to make it possible to remove records
* originating from connection with key[1] in_phone_hash
* value. Note that this is close to being classified
* as a nasty hack.
*
* @param key Array of keys.
* @param keys Must be lesser or equal to 3.
* @param item Pointer to a hash table item.
*
* @return Non-zero if the key matches the item, zero otherwise.
*
*/
int ns_compare(unsigned long key[], hash_count_t keys, link_t *item)
{
hashed_service_t *hs = hash_table_get_instance(item, hashed_service_t, link);
if (keys == 2)
return key[1] == hs->in_phone_hash;
else
return key[0] == hs->service;
}
/** Perform actions after removal of item from the hash table.
*
* @param item Item that was removed from the hash table.
*
*/
void ns_remove(link_t *item)
{
free(hash_table_get_instance
(item
, hashed_service_t
, link
)); }
/**
* @}
*/