NEWS.adoc, drivers/apc_modbus.c: _apc_modbus_usb_callback(): handle c…

…ommon return codes from matcher methods, like libusb1.c does [#2609]

Notably, handle active rejection of a candidate device by the matcher
properly - go try the next device!

Signed-off-by: Jim Klimov <[email protected]>

NEWS.adoc

@@ -374,6 +374,10 @@ https://github.com/networkupstools/nut/milestone/11
    to have fixed a Segmentation Fault seen in earlier NUT releases with
    some of the devices supported by this driver. [#2427]
 
+ - apc_modbus driver should now properly handle mismatches of criteria passed
+   to the regular expression matcher (e.g. serial number) allowing several USB
+   devices to be monitored without conflict. [#2609]
+
  - phoenixcontact_modbus driver: Introduced Phoenix Contact QUINT4-UPS/24DC
    management (only new modbus addresses). [#2689, #2716]
 

drivers/apc_modbus.c

@@ -1739,6 +1739,16 @@ static int _apc_modbus_usb_callback(const modbus_usb_device_t *device)
 		if (ret == 1) {
 			/* known good hit */
 			break;
+		} else if (ret == 0) {
+			/* known active rejection */
+			upsdebugx(2, "%s: Device does not match - skipping", __func__);
+			/* go to next device that libmodbus would suggest and use this callback again */
+			return -1;
+		} else if (ret == -1) {
+			fatal_with_errno(EXIT_FAILURE, "%s: matcher", __func__);
+		} else if (ret == -2) {
+			upsdebugx(2, "%s: matcher: unspecified error", __func__);
+			return -1;
 		}
 
 		current_matcher = current_matcher->next;