fix segfault when JSIOCGAXMAP/JSIOCGBTNMAP dont work

http://bugs.gentoo.org/132607

patch by Matt Anderson

--- utils/jstest.c
+++ utils/jstest.c
@@ -76,6 +76,7 @@ int main (int argc, char **argv)
 	char name[NAME_LENGTH] = "Unknown";
 	uint16_t btnmap[KEY_MAX - BTN_MISC + 1];
 	uint8_t axmap[ABS_MAX + 1];
+	int btnmap_ok, axismap_ok;
 
 	if (argc < 2 || argc > 3 || !strcmp("--help", argv[1])) {
 		puts("");
@@ -99,21 +100,29 @@ int main (int argc, char **argv)
 	ioctl(fd, JSIOCGAXES, &axes);
 	ioctl(fd, JSIOCGBUTTONS, &buttons);
 	ioctl(fd, JSIOCGNAME(NAME_LENGTH), name);
-	ioctl(fd, JSIOCGAXMAP, axmap);
-	ioctl(fd, JSIOCGBTNMAP, btnmap);
+	axismap_ok = ioctl(fd, JSIOCGAXMAP, axmap);
+	btnmap_ok = ioctl(fd, JSIOCGBTNMAP, btnmap);
 
 
 	printf("Driver version is %d.%d.%d.\n",
 		version >> 16, (version >> 8) & 0xff, version & 0xff);
 
 	printf("Joystick (%s) has %d axes (", name, axes);
-	for (i = 0; i < axes; i++)
-		printf("%s%s", i > 0 ? ", " : "", axis_names[axmap[i]]);
+	if (!axismap_ok) {
+		for (i = 0; i < axes; i++)
+			printf("%s%s", i > 0 ? ", " : "", axis_names[axmap[i]]);
+	} else {
+		printf(" axismap never defined ");
+	}
 	puts(")");
 
 	printf("and %d buttons (", buttons);
-	for (i = 0; i < buttons; i++)
-		printf("%s%s", i > 0 ? ", " : "", button_names[btnmap[i] - BTN_MISC]);
+	if (!btnmap_ok) {
+		for (i = 0; i < buttons; i++)
+			printf("%s%s", i > 0 ? ", " : "", button_names[btnmap[i] - BTN_MISC]);
+	} else {
+		printf(" buttonmap never defined ");
+	}
 	puts(").");
 
 	printf("Testing ... (interrupt to exit)\n");