void init_global_data(global_data_t * data, int flavor,
int instance_id, int hal_size,
int rt_level, int user_level,
const char *name, int stack_size)
{
// force-lock - we're first, so thats a bit theoretical
rtapi_mutex_try(&(data->mutex));
// touch all memory exposed to RT
memset(data, 0, sizeof(global_data_t));
// lock the global data segment
if (flavor != RTAPI_POSIX_ID) {
if (mlock(data, sizeof(global_data_t))) {
syslog_async(LOG_ERR, "MSGD:%d mlock(global) failed: %d '%s'\n",
instance_id, errno,strerror(errno));
}
}
// report progress
data->magic = GLOBAL_INITIALIZING;
/* set version code so other modules can check it */
data->layout_version = GLOBAL_LAYOUT_VERSION;
data->instance_id = instance_id;
if ((name == NULL) || (strlen(name) == 0)) {
snprintf(data->instance_name, sizeof(data->instance_name),
"inst%d",rtapi_instance);
} else {
strncpy(data->instance_name,name, sizeof(data->instance_name));
}
// separate message levels for RT and userland
data->rt_msg_level = rt_level;
data->user_msg_level = user_level;
// next value returned by rtapi_init (userland threads)
// those dont use fixed sized arrays
// start at 1 because the meaning of zero is special
data->next_module_id = 1;
// tell the others what we determined as the proper flavor
data->rtapi_thread_flavor = flavor;
// HAL segment size
data->hal_size = hal_size;
// stack size passed to rtapi_task_new() in hal_create_thread()
data->hal_thread_stack_size = stack_size;
// init the error ring
ringheader_init(&data->rtapi_messages, 0, SIZE_ALIGN(MESSAGE_RING_SIZE), 0);
memset(&data->rtapi_messages.buf[0], 0, SIZE_ALIGN(MESSAGE_RING_SIZE));
// attach to the message ringbuffer
ringbuffer_init(&data->rtapi_messages, &rtapi_msg_buffer);
rtapi_msg_buffer.header->refcount = 1; // rtapi not yet attached
rtapi_msg_buffer.header->reader = getpid();
data->rtapi_messages.use_wmutex = 1; // locking hint
// demon pids
data->rtapi_app_pid = -1; // not yet started
data->rtapi_msgd_pid = 0;
/* done, release the mutex */
rtapi_mutex_give(&(data->mutex));
return;
}
int hal_ring_new(const char *name, int size, int sp_size, int mode)
{
hal_ring_t *rbdesc;
int *prev, next, cmp, retval;
int ring_id;
ringheader_t *rhptr;
CHECK_HALDATA();
CHECK_STRLEN(name, HAL_NAME_LEN);
CHECK_LOCK(HAL_LOCK_LOAD);
{
hal_ring_t *ptr __attribute__((cleanup(halpr_autorelease_mutex)));
rtapi_mutex_get(&(hal_data->mutex));
// make sure no such ring name already exists
if ((ptr = halpr_find_ring_by_name(name)) != 0) {
HALERR("ring '%s' already exists", name);
return -EEXIST;
}
// allocate a new ring id - needed since we dont track ring shm
// segments in RTAPI
if ((ring_id = next_ring_id()) < 0) {
HALERR("cant allocate new ring id for '%s'", name);
return -ENOMEM;
}
// allocate a new ring descriptor
if ((rbdesc = alloc_ring_struct()) == 0)
NOMEM("ring '%s'", name);
rbdesc->handle = rtapi_next_handle();
rbdesc->flags = mode;
rbdesc->ring_id = ring_id;
// make total allocation fit ringheader, ringbuffer and scratchpad
rbdesc->total_size = ring_memsize( rbdesc->flags, size, sp_size);
if (rbdesc->flags & ALLOC_HALMEM) {
void *ringmem = shmalloc_up(rbdesc->total_size);
if (ringmem == NULL)
NOMEM("ring '%s' size %d - insufficient HAL memory for ring",
name,rbdesc->total_size);
rbdesc->ring_offset = SHMOFF(ringmem);
rhptr = ringmem;
} else {
// allocate shared memory segment for ring and init
rbdesc->ring_shmkey = OS_KEY((RTAPI_RING_SHM_KEY + ring_id), rtapi_instance);
int shmid;
// allocate an RTAPI shm segment owned by HAL_LIB_xxx
if ((shmid = rtapi_shmem_new(rbdesc->ring_shmkey, lib_module_id,
rbdesc->total_size)) < 0)
NOMEM("rtapi_shmem_new(0x%8.8x,%d) failed: %d",
rbdesc->ring_shmkey, lib_module_id,
rbdesc->total_size);
// map the segment now so we can fill in the ringheader details
if ((retval = rtapi_shmem_getptr(shmid,
(void **)&rhptr, 0)) < 0)
NOMEM("rtapi_shmem_getptr for %d failed %d",
shmid, retval);
}
HALDBG("created ring '%s' in %s, total_size=%d",
name, (rbdesc->flags & ALLOC_HALMEM) ? "halmem" : "shm",
rbdesc->total_size);
ringheader_init(rhptr, rbdesc->flags, size, sp_size);
rhptr->refcount = 0; // on hal_ring_attach: increase; on hal_ring_detach: decrease
rtapi_snprintf(rbdesc->name, sizeof(rbdesc->name), "%s", name);
rbdesc->next_ptr = 0;
// search list for 'name' and insert new structure
prev = &(hal_data->ring_list_ptr);
next = *prev;
while (1) {
if (next == 0) {
/* reached end of list, insert here */
rbdesc->next_ptr = next;
*prev = SHMOFF(rbdesc);
return 0;
}
ptr = SHMPTR(next);
cmp = strcmp(ptr->name, rbdesc->name);
if (cmp > 0) {
/* found the right place for it, insert here */
rbdesc->next_ptr = next;
*prev = SHMOFF(rbdesc);
return 0;
}
/* didn't find it yet, look at next one */
prev = &(ptr->next_ptr);
next = *prev;
}
// automatic unlock by scope exit
}
}
