/**
* This routine opens an ET system for client use.
*
* Given an ET system on the same host, this routine will map the system's shared memory into the
* user's space. It also starts up a thread to produce a heartbeat and a second thread to monitor
* the ET system's heartbeat. If the ET system is remote, a network connection is made to it.<p>
*
* The ET system is implemented as a single memory mapped file of the name, filename.
* This routine should only be called once, before all other ET routines are used, or after a
* system has been closed with a call to @ref et_close or @ref et_forcedclose. A successful return
* from this routine assures connection to an ET system which is up and running.
* <b><i>IT IS CRUCIAL THAT THE USER GET A RETURN VALUE OF "ET_OK" IF THE USER WANTS AN ET SYSTEM
* GUARANTEED TO FUNCTION.</i></b><p>
*
* The user may open an ET system on a remote host. ET decides whether the user is on the same
* as or a different machine than the system. If the determination is made that the user is on
* another computer, then network connections are made to that system.<p>
*
* @param id pointer to ET system id which gets filled in if ET system successfully opened.
* @param filename name of ET system file.
* @param openconfig ET system open configuration.
*
* @returns @ref ET_OK if successful
* @returns @ref ET_ERROR if bad arg, ET name too long, cannot initialize id,
* creating/using shared memory, incompatible values for @ref ET_STATION_SELECT_INTS,
* or ET system is 32 bit and this program is 64 bit,
* @returns @ref ET_ERROR_TIMEOUT if the ET system is still not active before the routine returns.
* @returns @ref ET_ERROR_TOOMANY if broad/multicasting and too many responses
* @returns @ref ET_ERROR_REMOTE if broad/multicasting and cannot find/connect to ET system or
* cannot allocate memory or ET system & user use different versions of ET, or
* the host has a strange byte order.
* @returns @ref ET_ERROR_READ if network read error.
* @returns @ref ET_ERROR_WRITE if network write error.
*/
int et_open(et_sys_id *id, const char *filename, et_openconfig openconfig) {
int status, auto_open=0, err, locality;
et_open_config *config;
et_openconfig auto_config = NULL;
int def_debug;
if (openconfig == NULL) {
auto_open = 1;
if (et_open_config_init(&auto_config) == ET_ERROR) {
et_logmsg("ERROR", "et_open, null arg for openconfig, cannot use default\n");
return ET_ERROR;
}
openconfig = auto_config;
}
config = (et_open_config *) openconfig;
err = ET_OK;
/* argument checking */
if ((filename == NULL) || (config->init != ET_STRUCT_OK)) {
et_logmsg("ERROR", "et_open, bad argument\n");
err = ET_ERROR;
}
else if (strlen(filename) > ET_FILENAME_LENGTH - 1) {
et_logmsg("ERROR", "et_open, ET name too long\n");
err = ET_ERROR;
}
if (err != ET_OK) {
if (auto_open == 1) {
et_open_config_destroy(auto_config);
}
return err;
}
/* initialize id */
if (et_id_init(id) != ET_OK) {
et_logmsg("ERROR", "et_open, cannot initialize id\n");
return ET_ERROR;
}
if (et_open_config_getdebugdefault(openconfig, &def_debug) != ET_OK) {
def_debug = ET_DEBUG_ERROR;
}
et_system_setdebug(*id, def_debug);
/* Decide whether we are looking for the ET system locally,
* locally on some non-mutex-sharing operating
* system, remotely, or anywhere.
*/
locality = et_findlocality(filename, openconfig);
/* if host is local ... */
if (locality == ET_LOCAL) {
status = etl_open(id, filename, openconfig);
/* If this is a Java-based ET sys, try opening it as remote client. */
if (status == ET_ERROR_JAVASYS) {
et_logmsg("ERROR", "et_open: cannot open Java ET file, try as remote client\n");
status = etr_open(id, filename, openconfig);
}
}
/* else if host is remote ... */
else if (locality == ET_REMOTE) {
status = etr_open(id, filename, openconfig);
}
/* else if host is local on Linux ... */
else if (locality == ET_LOCAL_NOSHARE) {
status = etn_open(id, filename, openconfig);
}
/* else if too many systems responded and we have return error policy ... */
else if ((locality == ET_ERROR_TOOMANY) && (config->policy == ET_POLICY_ERROR)) {
if (auto_open == 1) {
et_open_config_destroy(auto_config);
}
et_logmsg("ERROR", "et_open: too many ET systems of that name responded\n");
return ET_ERROR;
}
/* else did not find ET system by broad/multicasting. In
* this case, try to open a local system first then remote.
*/
else {
int shared = et_sharedmutex();
/* if local operating system can share pthread mutexes ... */
if (shared == ET_MUTEX_SHARE) {
status = etl_open(id, filename, openconfig);
}
else {
status = etn_open(id, filename, openconfig);
}
if (status != ET_OK) {
status = etr_open(id, filename, openconfig);
}
}
if (status != ET_OK) {
et_id_destroy(*id);
}
if (auto_open == 1) {
et_open_config_destroy(auto_config);
}
return status;
}
int et_open(et_sys_id *id, const char *filename, et_openconfig openconfig)
{
int status, auto_open=0, err;
et_open_config *config;
et_openconfig auto_config = NULL;
int def_debug;
if (openconfig == NULL) {
auto_open = 1;
if (et_open_config_init(&auto_config) == ET_ERROR) {
et_logmsg("ERROR", "et_open, null arg for openconfig, cannot use default\n");
return ET_ERROR;
}
openconfig = auto_config;
}
config = (et_open_config *) openconfig;
err = ET_OK;
/* argument checking */
if ((filename == NULL) || (config->init != ET_STRUCT_OK)) {
et_logmsg("ERROR", "et_open, bad argument\n");
err = ET_ERROR;
}
else if (strlen(filename) > ET_FILENAME_LENGTH - 1) {
et_logmsg("ERROR", "et_open, ET name too long\n");
err = ET_ERROR;
}
if (err != ET_OK) {
if (auto_open == 1) {
et_open_config_destroy(auto_config);
}
return err;
}
/* initialize id */
if (et_id_init(id) != ET_OK) {
et_logmsg("ERROR", "et_open, cannot initialize id\n");
return ET_ERROR;
}
if (et_open_config_getdebugdefault(openconfig, &def_debug) != ET_OK) {
def_debug = ET_DEBUG_ERROR;
}
et_system_setdebug(*id, def_debug);
/* We depart from the original version of et_open since
* this ET client will attach to an ET system remotely by definition.
* Force the configuration to make a tcp connection to the ET system,
* even if it's not remote.
*/
config->mode = ET_HOST_AS_REMOTE;
status = etr_open(id, filename, openconfig);
if (status != ET_OK) {
et_id_destroy(*id);
}
if (auto_open == 1) {
et_open_config_destroy(auto_config);
}
return status;
}
