static void send_message_to_process(endpoint_t who, int ret, int ignore)
{
message m;
m.m_type = ret;
ipc_sendnb(who, &m);
}
/*===========================================================================*
* reply *
*===========================================================================*/
static void reply(message *m_out, endpoint_t whom, int result)
{
/* Send a reply to a user process. If the send fails, just ignore it. */
int r;
m_out->m_type = result;
r = ipc_sendnb(whom, m_out);
if (r != OK) {
printf("VFS: %d couldn't send reply %d to %d: %d\n", mthread_self(),
result, whom, r);
util_stacktrace();
}
}
/*===========================================================================*
* send_reply *
*===========================================================================*/
static void send_reply(endpoint_t endpt, message *m_ptr, int ipc_status)
{
/* Send a reply message to a request. */
int r;
/* If we would block sending the message, send it asynchronously. The NOREPLY
* flag is set because the caller may also issue a SENDREC (mixing sync and
* async comm), and the asynchronous reply could otherwise end up satisfying
* the SENDREC's receive part, after which our next SENDNB call would fail.
*/
if (IPC_STATUS_CALL(ipc_status) == SENDREC)
r = ipc_sendnb(endpt, m_ptr);
else
r = asynsend3(endpt, m_ptr, AMF_NOREPLY);
if (r != OK)
printf("blockdriver: unable to send reply to %d: %d\n", endpt, r);
}
int
main(int argc, char **argv)
{
int r;
endpoint_t caller;
struct tm t;
message m;
int ipc_status, reply_status;
env_setargs(argc, argv);
sef_local_startup();
while (TRUE) {
/* Receive Message */
r = sef_receive_status(ANY, &m, &ipc_status);
if (r != OK) {
log_warn(&log, "sef_receive_status() failed\n");
continue;
}
if (is_ipc_notify(ipc_status)) {
/* Do not reply to notifications. */
continue;
}
caller = m.m_source;
log_debug(&log, "Got message 0x%x from 0x%x\n", m.m_type,
caller);
switch (m.m_type) {
case RTCDEV_GET_TIME:
/* Any user can read the time */
reply_status = rtc.get_time(&t, m.m_lc_readclock_rtcdev.flags);
if (reply_status != OK) {
break;
}
/* write results back to calling process */
reply_status =
store_t(caller, m.m_lc_readclock_rtcdev.tm, &t);
break;
case RTCDEV_SET_TIME:
/* Only super user is allowed to set the time */
if (getnuid(caller) == SUPER_USER) {
/* read time from calling process */
reply_status =
fetch_t(caller, m.m_lc_readclock_rtcdev.tm,
&t);
if (reply_status != OK) {
break;
}
reply_status =
rtc.set_time(&t, m.m_lc_readclock_rtcdev.flags);
} else {
reply_status = EPERM;
}
break;
case RTCDEV_PWR_OFF:
/* Only PM is allowed to set the power off time */
if (caller == PM_PROC_NR) {
reply_status = rtc.pwr_off();
} else {
reply_status = EPERM;
}
break;
default:
/* Unrecognized call */
reply_status = EINVAL;
break;
}
/* Send Reply */
m.m_type = RTCDEV_REPLY;
m.m_readclock_lc_rtcdev.status = reply_status;
log_debug(&log, "Sending Reply");
r = ipc_sendnb(caller, &m);
if (r != OK) {
log_warn(&log, "ipc_sendnb() failed\n");
continue;
}
}
rtc.exit();
return 0;
}
/*===========================================================================*
* do_semop *
*===========================================================================*/
int do_semop(message *m)
{
int id, i, j, r;
struct sembuf *sops;
unsigned int nsops;
struct sem_struct *sem;
int no_reply = 0;
id = m->m_lc_ipc_semop.id;
nsops = m->m_lc_ipc_semop.size;
r = EINVAL;
if (!(sem = sem_find_id(id)))
goto out;
if (nsops <= 0)
goto out;
r = E2BIG;
if (nsops > SEMOPM)
goto out;
/* check for read permission */
r = EACCES;
if (!check_perm(&sem->semid_ds.sem_perm, who_e, 0444))
goto out;
/* get the array from user application */
r = ENOMEM;
sops = malloc(sizeof(struct sembuf) * nsops);
if (!sops)
goto out_free;
r = sys_datacopy(who_e, (vir_bytes) m->m_lc_ipc_semop.ops,
SELF, (vir_bytes) sops,
sizeof(struct sembuf) * nsops);
if (r != OK) {
r = EINVAL;
goto out_free;
}
#ifdef DEBUG_SEM
for (i = 0; i < nsops; i++)
printf("SEMOP: num:%d op:%d flg:%d\n",
sops[i].sem_num, sops[i].sem_op, sops[i].sem_flg);
#endif
/* check for value range */
r = EFBIG;
for (i = 0; i < nsops; i++)
if (sops[i].sem_num >= sem->semid_ds.sem_nsems)
goto out_free;
/* check for duplicate number */
r = EINVAL;
for (i = 0; i < nsops; i++)
for (j = i + 1; j < nsops; j++)
if (sops[i].sem_num == sops[j].sem_num)
goto out_free;
/* check for EAGAIN error */
r = EAGAIN;
for (i = 0; i < nsops; i++) {
int op_n, val;
op_n = sops[i].sem_op;
val = sem->sems[sops[i].sem_num].semval;
if ((sops[i].sem_flg & IPC_NOWAIT) &&
((!op_n && val) ||
(op_n < 0 &&
-op_n > val)))
goto out_free;
}
/* there will be no errors left, so we can go ahead */
for (i = 0; i < nsops; i++) {
struct semaphore *s;
int op_n;
s = &sem->sems[sops[i].sem_num];
op_n = sops[i].sem_op;
s->sempid = getnpid(who_e);
if (op_n > 0) {
/* check for alter permission */
r = EACCES;
if (!check_perm(&sem->semid_ds.sem_perm, who_e, 0222))
goto out_free;
s->semval += sops[i].sem_op;
} else if (!op_n) {
if (s->semval) {
/* put the process asleep */
s->semzcnt++;
s->zlist = realloc(s->zlist, sizeof(struct waiting) * s->semzcnt);
if (!s->zlist) {
printf("IPC: zero waiting list lost...\n");
break;
}
s->zlist[s->semzcnt-1].who = who_e;
s->zlist[s->semzcnt-1].val = op_n;
#ifdef DEBUG_SEM
printf("SEMOP: Put into sleep... %d\n", who_e);
#endif
no_reply++;
}
} else {
/* check for alter permission */
r = EACCES;
if (!check_perm(&sem->semid_ds.sem_perm, who_e, 0222))
goto out_free;
if (s->semval >= -op_n)
s->semval += op_n;
else {
/* put the process asleep */
s->semncnt++;
s->nlist = realloc(s->nlist, sizeof(struct waiting) * s->semncnt);
if (!s->nlist) {
printf("IPC: increase waiting list lost...\n");
break;
}
s->nlist[s->semncnt-1].who = who_e;
s->nlist[s->semncnt-1].val = -op_n;
no_reply++;
}
}
}
r = OK;
out_free:
free(sops);
out:
/* if we reach here by errors
* or with no errors but we should reply back.
*/
if (r != OK || !no_reply) {
m->m_type = r;
ipc_sendnb(who_e, m);
}
/* awaken process if possible */
update_semaphores();
return 0;
}
int
main(int argc, char *argv[])
{
int r, i;
struct tm t;
endpoint_t user, caller;
message m;
int ipc_status, reply_status;
env_setargs(argc, argv);
r = i2cdriver_env_parse(&bus, &addresses[0], valid_addrs);
if (r < 0) {
log_warn(&log, "Expecting -args 'bus=X address=0xYY'\n");
log_warn(&log, "Example -args 'bus=1 address=0x48'\n");
return EXIT_FAILURE;
} else if (r > 0) {
log_warn(&log,
"Invalid slave address for device, expecting 0x48\n");
return EXIT_FAILURE;
}
sef_local_startup();
while (TRUE) {
/* Receive Message */
r = sef_receive_status(ANY, &m, &ipc_status);
if (r != OK) {
log_warn(&log, "sef_receive_status() failed\n");
continue;
}
if (is_ipc_notify(ipc_status)) {
if (m.m_source == DS_PROC_NR) {
for (i = 0; i < NADDRESSES; i++) {
/* changed state, update endpoint */
i2cdriver_handle_bus_update
(&bus_endpoint, bus, addresses[i]);
}
}
/* Do not reply to notifications. */
continue;
}
caller = m.m_source;
log_debug(&log, "Got message 0x%x from 0x%x\n", m.m_type,
caller);
switch (m.m_type) {
case RTCDEV_GET_TIME_G:
/* Any user can read the time */
reply_status = rtc_get_time(&t, m.m_lc_readclock_rtcdev.flags);
if (reply_status != OK) {
break;
}
/* write results back to calling process */
reply_status =
store_t(caller, m.m_lc_readclock_rtcdev.grant, &t);
break;
case RTCDEV_SET_TIME_G:
/* Only super user is allowed to set the time */
if (getnuid(caller) == SUPER_USER) {
/* read time from calling process */
reply_status =
fetch_t(caller,
m.m_lc_readclock_rtcdev.grant, &t);
if (reply_status != OK) {
break;
}
reply_status =
rtc_set_time(&t,
m.m_lc_readclock_rtcdev.flags);
} else {
reply_status = EPERM;
}
break;
case RTCDEV_PWR_OFF:
reply_status = ENOSYS;
break;
default:
/* Unrecognized call */
reply_status = EINVAL;
break;
}
/* Send Reply */
m.m_type = RTCDEV_REPLY;
m.m_readclock_lc_rtcdev.status = reply_status;
log_debug(&log, "Sending Reply");
r = ipc_sendnb(caller, &m);
if (r != OK) {
log_warn(&log, "ipc_sendnb() failed\n");
continue;
}
}
rtc_exit();
return 0;
}
