+static int setup_done;
+
+/*---------- operations ----------*/
+
+static int setup_failure(Tcl_Interp *ip, int r) {
+#define N 4
+ Tcl_Obj *codelist[N];
+ codelist[0]= cht_ret_string(ip,"WIRINGPI");
+ codelist[1]= cht_ret_string(ip,"ERROR");
+ codelist[2]= cht_ret_string(ip,"SETUP");
+ codelist[3]= cht_ret_int(ip,r);
+ Tcl_SetObjResult(ip, Tcl_NewListObj(N, codelist));
+#undef N
+ Tcl_SetResult(ip, (char*)"wiringpi initialisation error", TCL_STATIC);
+ return TCL_ERROR;
+}
+
+static int ensure_setup(Tcl_Interp *ip) {
+ if (!setup_done) {
+ int r = wiringPiSetup();
+ if (r) return setup_failure(ip, r);
+ setup_done = 1;
+ }
+ return TCL_OK;
+}
+
+int cht_do_wiringpitcl_setup(ClientData cd, Tcl_Interp *ip,
+ int objc, Tcl_Obj *const *objv) {
+ int r;
+ int rc;
+
+ if (setup_done)
+ return cht_staticerr(ip,"wiringpi setup called again",
+ "WIRINGPI FORBIDDEN-REINIT SETUP");
+
+ if (*objv) {
+ const char *modeopt;
+ rc = cht_pat_string(ip,*objv++,&modeopt);
+ if (rc) return rc;
+ if (modeopt[0] != '-' || !modeopt[1] || modeopt[2])
+ return cht_staticerr(ip,"wiringpi setup option wrong syntax", 0);
+ if (*objv)
+ return cht_staticerr(ip,"wiringpi setup too many arguments", 0);
+ switch (modeopt[1]) {
+ case 'g': r = wiringPiSetupGpio(); break;
+ case '1': r = wiringPiSetupPhys(); break;
+ case 'p': r = piFaceSetup(2000 /* ?! copied from gpio.c* */); break;
+ default:
+ return cht_staticerr(ip,"wiringpi setup option unknown value", 0);
+ }
+ } else {
+ r = wiringPiSetup();
+ }
+ if (r) return setup_failure(ip, r);
+ return TCL_OK;
+}
+