Enhance USB device and subdriver matching in usbhid-ups to be on par with nutdrv_qx

[jimklimov]

Closes: #1369

By side effect, moves detection of libregex build parameters (if any are needed) into a separate m4 script, and creates automake and C macros to shield about their presence. Generic regex helper methods (not intimate to USB) moved to common.c/h. Also, found that clients/* were built by default with libcommon.la (not libcommonclient.la) and pulled extra dependencies like -lsystemd that (most of) the clients should not care about - also addressed.

Example testing outcome: this change allows poking an Eaton device with a "not-its" (Tripplite) subdriver, even getting a bit of info as seen below.

Unlike nutdrv_qx, for the iteration shown below I did not constrain this feature to require at least a specified vendorid and productid in configuration, but makes sense to add it. As seen in the "screenshot", the driver opened the first device it had FS-level permission to access.

# Full built-in name:
:; ./drivers/usbhid-ups -DD -s test -x port=auto -x subdriver='TrippLite HID 0.85' -d1
...
   0.002171     [D2] Checking device 4 of 9 (1D6B/0003)
   0.002175     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.002177     [D2] Checking device 5 of 9 (0463/FFFF)
   0.424708     [D2] - VendorID: 0463
   0.424724     [D2] - ProductID: ffff
   0.424730     [D2] - Manufacturer: EATON
   0.424734     [D2] - Product: Ellipse ECO
   0.424739     [D2] - Serial Number: 000000000
   0.424750     [D2] - Bus: 003
   0.424756     [D2] - Bus Port: 002
   0.424761     [D2] - Device: 007
   0.424764     [D2] - Device release number: 0100
   0.424768     [D2] Trying to match device
   0.424773     [D2] match_function_subdriver_name: matching a subdriver by explicit name/regex: 'TrippLite HID 0.85'...
   0.424779     [D2] match_function_subdriver_name: found a match: TrippLite HID 0.85
   0.424783     [D2] Device matches
   0.424787     [D2] Reading first configuration descriptor
   0.424810     [D2] Claimed interface 0 successfully
...

Similarly by substring regex which is a more likely use-case:

:; ./drivers/usbhid-ups -DD -s test -x port=auto -x subdriver='tripplite' -d1
...
   0.003256     [D2] Checking device 4 of 9 (1D6B/0003)
   0.003261     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.003264     [D2] Checking device 5 of 9 (0463/FFFF)
   0.424078     [D2] - VendorID: 0463
   0.424092     [D2] - ProductID: ffff
   0.424097     [D2] - Manufacturer: EATON
   0.424100     [D2] - Product: Ellipse ECO
   0.424103     [D2] - Serial Number: 000000000
   0.424107     [D2] - Bus: 003
   0.424111     [D2] - Bus Port: 002
   0.424115     [D2] - Device: 007
   0.424119     [D2] - Device release number: 0100
   0.424122     [D2] Trying to match device
   0.424127     [D2] match_function_subdriver_name: matching a subdriver by explicit name/regex: 'tripplite'...
   0.424138     [D2] match_function_subdriver_name: retry matching by regex 'as is'
   0.424228     [D2] match_function_subdriver_name: retry matching by regex with added '.*'
   0.424259     [D2] match_function_subdriver_name: found a match: TrippLite HID 0.85
   0.424263     [D2] Device matches
   0.424266     [D2] Reading first configuration descriptor
   0.424302     [D2] Claimed interface 0 successfully
   0.491079     [D2] Retrieved HID descriptor (expected 9, got 9)
   0.491091     [D2] HID descriptor length 909
   3.661073     [D2] Report Descriptor size = 909
   3.661117     [D2] match_function_subdriver_name: matching a subdriver by explicit name/regex: 'tripplite'...
   3.661122     [D2] match_function_subdriver_name: retry matching by regex 'as is'
   3.661156     [D2] match_function_subdriver_name: retry matching by regex with added '.*'
   3.661170     [D2] match_function_subdriver_name: found a match: TrippLite HID 0.85
   3.661172     Using subdriver: TrippLite HID 0.85
   3.661175     [D1] 94 HID objects found
   3.703060     [D1] Path: UPS.BatterySystem.Battery.AudibleAlarmControl, Type: Feature, ReportID: 0x20, Offset: 0, Size: 8, Value: 1
...
   6.551087     [D1] upsdrv_updateinfo...
   7.301215     [D2] nut_libusb_get_interrupt: Connection timed out
   7.301236     [D1] Got 0 HID objects...
   7.301245     [D1] Quick update...
   7.301255     [D2] Path: UPS.PowerSummary.PresentStatus.ACPresent, Type: Feature, ReportID: 0x01, Offset: 0, Size: 1, Value: 1
   7.301262     [D2] Path: UPS.PowerSummary.PresentStatus.BelowRemainingCapacityLimit, Type: Feature, ReportID: 0x01, Offset: 1, Size: 1, Value: 0
   7.301270     [D2] Path: UPS.PowerSummary.PresentStatus.Charging, Type: Feature, ReportID: 0x01, Offset: 2, Size: 1, Value: 1
   7.301279     [D2] Path: UPS.PowerSummary.PresentStatus.Discharging, Type: Feature, ReportID: 0x01, Offset: 4, Size: 1, Value: 0
battery.charge: 100
battery.charge.low: 20
battery.runtime: 1312
battery.type: PbAc
device.mfr: EATON
device.model: Ellipse ECO
device.serial: 000000000
device.type: ups
driver.debug: 2
driver.flag.allow_killpower: 0
driver.name: usbhid-ups
driver.parameter.pollfreq: 30
driver.parameter.pollinterval: 2
driver.parameter.port: auto
driver.parameter.subdriver: tripplite
driver.parameter.synchronous: auto
driver.state: dumping
driver.version: 2.8.0-2497-gc83ad2e3f
driver.version.data: TrippLite HID 0.85
driver.version.internal: 0.52
driver.version.usb: libusb-1.0.24 (API: 0x1000108)
input.transfer.high: 264.0
input.transfer.low: 161.0
output.voltage: 230.0
ups.beeper.status: enabled
ups.mfr: EATON
ups.model: Ellipse ECO
ups.productid: ffff
ups.serial: 000000000
ups.status: OL CHRG
ups.vendorid: 0463
   7.301370     [D1] upsdrv_cleanup...

Example of standard matching options still being honoured (using locally-absent vendorid):

# ./drivers/usbhid-ups -DDD -s test -x port=auto -x subdriver='tripplite' -d1 -x vendorid=1234
Network UPS Tools - Generic HID driver 0.52 (2.8.0-2497-gc83ad2e3f)
USB communication driver (libusb 1.0) 0.46
   0.000000     [D3] main_arg: var='port' val='auto'
   0.000012     [D3] main_arg: var='subdriver' val='tripplite'
   0.000020     [D3] main_arg: var='vendorid' val='1234'
   0.000027     [D1] Network UPS Tools version 2.8.0-2497-gc83ad2e3f (release/snapshot of 2.8.0.1) built with gcc (Debian 10.2.1-6) 10.2.1 20210110 and configured with flags: --with-user=nut --with-group=nut --with-all --with-docs=man --sysconfdir=/etc/nut --enable-silent-rules
   0.000033     [D1] debug level is '3'
   0.000618     [D1] Succeeded to become_user(nut): now UID=77 GID=77
   0.000631     [D1] upsdrv_initups (non-SHUT)...
   0.000635     [D2] Initializing an USB-connected UPS with library libusb-1.0.24 (API: 0x1000108) (NUT subdriver name='USB communication driver (libusb 1.0)' ver='0.46')
   0.004118     [D2] Checking device 1 of 9 (1D6B/0003)
   0.004140     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.004145     [D2] Checking device 2 of 9 (03F0/0D4A)
   0.004152     [D1] Failed to open device (03F0/0D4A), skipping: Access denied (insufficient permissions)
   0.004156     [D2] Checking device 3 of 9 (1D6B/0002)
   0.004162     [D1] Failed to open device (1D6B/0002), skipping: Access denied (insufficient permissions)
   0.004165     [D2] Checking device 4 of 9 (1D6B/0003)
   0.004171     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.004174     [D2] Checking device 5 of 9 (0463/FFFF)
   0.428129     [D2] - VendorID: 0463
   0.428143     [D2] - ProductID: ffff
   0.428148     [D2] - Manufacturer: EATON
   0.428154     [D2] - Product: Ellipse ECO
   0.428161     [D2] - Serial Number: 000000000
   0.428165     [D2] - Bus: 003
   0.428168     [D2] - Bus Port: 002
   0.428171     [D2] - Device: 007
   0.428175     [D2] - Device release number: 0100
   0.428178     [D2] Trying to match device
   0.428183     [D2] match_function_subdriver_name: matching a subdriver by explicit name/regex: 'tripplite'...
   0.428194     [D2] match_function_subdriver_name: retry matching by regex 'as is'
   0.428253     [D2] match_function_subdriver_name: retry matching by regex with added '.*'
   0.428285     [D2] match_function_subdriver_name: found a match: TrippLite HID 0.85
   0.428289     [D3] match_function_regex: matching a device...
   0.428293     [D2] match_function_regex: failed match of VendorID:  463
   0.428297     [D2] Device does not match - skipping
   0.428308     [D2] Checking device 6 of 9 (1D6B/0002)
   0.428322     [D1] Failed to open device (1D6B/0002), skipping: Access denied (insufficient permissions)
   0.428325     [D2] Checking device 7 of 9 (1D6B/0003)
   0.428332     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.428336     [D2] Checking device 8 of 9 (048D/5702)
   0.428342     [D1] Failed to open device (048D/5702), skipping: Access denied (insufficient permissions)
   0.428345     [D2] Checking device 9 of 9 (1D6B/0002)
   0.428351     [D1] Failed to open device (1D6B/0002), skipping: Access denied (insufficient permissions)
   0.428356     [D2] libusb1: No appropriate HID device found
   0.428361     libusb1: Could not open any HID devices: insufficient permissions on everything
   0.428365     No matching HID UPS found

Also fixes some issues with nut-scanner reporting of suspect serial numbers, and quiesces some warnings for new clang versions (which we can't do much about in practice => CC #823 "fightwarn" effort).

[jimklimov]

With the requirement of IDs added, it behaves like this:

:; ./drivers/usbhid-ups -DDD -s test -x port=auto -x subdriver='tripplite' -d1 -x vendorid=1234
Network UPS Tools - Generic HID driver 0.52 (2.8.0-2498-g05b522ebd)
USB communication driver (libusb 1.0) 0.46
   0.000000     [D3] main_arg: var='port' val='auto'
   0.000014     [D3] main_arg: var='subdriver' val='tripplite'
   0.000027     [D3] main_arg: var='vendorid' val='1234'
   0.000034     [D1] Network UPS Tools version 2.8.0-2498-g05b522ebd (release/snapshot of 2.8.0.1) built with gcc (Debian 10.2.1-6) 10.2.1 20210110 and configured with flags: --with-user=nut --with-group=nut --with-all --with-docs=man --sysconfdir=/etc/nut --enable-silent-rules
   0.000040     [D1] debug level is '3'
   0.000723     [D1] Succeeded to become_user(nut): now UID=77 GID=77
   0.000760     [D1] upsdrv_initups (non-SHUT)...
   0.000768     [D2] Initializing an USB-connected UPS with library libusb-1.0.24 (API: 0x1000108) (NUT subdriver name='USB communication driver (libusb 1.0)' ver='0.46')
   0.004320     [D2] Checking device 1 of 9 (1D6B/0003)
   0.004339     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.004344     [D2] Checking device 2 of 9 (03F0/0D4A)
   0.004352     [D1] Failed to open device (03F0/0D4A), skipping: Access denied (insufficient permissions)
   0.004356     [D2] Checking device 3 of 9 (1D6B/0002)
   0.004362     [D1] Failed to open device (1D6B/0002), skipping: Access denied (insufficient permissions)
   0.004366     [D2] Checking device 4 of 9 (1D6B/0003)
   0.004372     [D1] Failed to open device (1D6B/0003), skipping: Access denied (insufficient permissions)
   0.004375     [D2] Checking device 5 of 9 (0463/FFFF)
   0.426457     [D2] - VendorID: 0463
   0.426470     [D2] - ProductID: ffff
   0.426475     [D2] - Manufacturer: EATON
   0.426479     [D2] - Product: Ellipse ECO
   0.426483     [D2] - Serial Number: 000000000
   0.426487     [D2] - Bus: 003
   0.426490     [D2] - Bus Port: 002
   0.426494     [D2] - Device: 007
   0.426498     [D2] - Device release number: 0100
   0.426501     [D2] Trying to match device
   0.426538     [D2] match_function_subdriver_name: matching a subdriver by explicit name/regex: 'tripplite'...
   0.426568     [D2] match_function_subdriver_name: retry matching by regex 'as is'
   0.426628     [D2] match_function_subdriver_name: retry matching by regex with added '.*'
   0.426655     [D2] match_function_subdriver_name: found a match: TrippLite HID 0.85
   0.426659     When specifying a subdriver, 'vendorid' and 'productid' are mandatory.

Subdriver confirmed matched (exists), but then aborts due to lack of both VID and PID (only one is given) before even checking them.