Upstreaming improvements from 42ity/nut fork #1316

A lot of work on NUT was done under the auspices of Eaton-backed 42ity project, as well as some earlier bundled releases that became part of its codebase. While much of the development was cross-posted for PRs, some was only pursued in the fork to perfect there first. 42ity took the decision to eventually move from the burden of maintaining a separate fork (thereby regularly solving merge conflicts) towards using the "upstream NUT" codebase directly, so I imported the "FTY" branch and identified the largest differing subjects to reconcile between the two:

• DMF feature (not in first wave, a very big subject in itself): lua, libxml2, HAVE_XMLLINT, reference some mapping functions in "standard" binary driver ... => Known remaining blockers (at least need to investigate if they still bite): DMF/FTY: Fix linking of libnutscan.so etc. to NOT pull in the libraries we plan to load dynamically #2349, DMF Branch : bad input files can core-dump the parser #470, DMF Branch : design and complete support for lookup functions #469;
• tools/nut-snmpinfo.py.in - generate .c vs .h (may be part of DMF-related structural changes)
• docs building (man-pages vs others; --with-doc=dist-auto / --with-doc=man=dist-auto) => issue Import from FTY branch: recipes to configure --with-docs=dist-auto #2340, PR Upstream from FTY branch: make distcheck-light-man and ./confgure --with-doc=man=dist-auto features #2473
• nut-conf and installer scripts => Import libconf/nutconf features #2283, Enable build of libconf/nutconf features by default #2290, Import CLI installer for a NUT bundle #2288 and docs: finalize re-licensing of scripts/installer … #2623 => https://github.com/networkupstools/nut/pulls?q=label%3Anutconf
• drivers/snmp-ups.c - semi-static values, ambient info, daisy-chain => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• snmp-ups: sysContact, sysLocation => snmp-ups: add sysContact and sysLocation support #320
• run-time debug settings via config files; separation of FG/BG runs from debug setting => drivers/main.c: allow to specify a user for each driver via ups.conf #1293
• stc.c: str_concat() => issue Import from FTY branch: fallback str_concat #2343 / PR common/str.c, include/str.h: introduce str_concat() #2476
• libcommonstr.la recipe (nut-scanner; later DMF per se) => common/Makefile.am, tools/nut-scanner/Makefile.am: Introduce libcommonstr.la #2478 and Revise libwincompat.la vs. libcommonstr.la helpers in libnutscan build recipe #2491
• libserial-nutscan.la recipe => Port recipe for libserial-nutscan.la from DMF/FTY branch and clean up nut-scanner makefile #2490
• nut-driver-enumerator-daemon => Nut driver enumerator optimize #682
• docs/man/nut-scanner.txt => solved by one of the resyncs from master... FTY remerge from master as of 2024-03-02 #2275?
• docs/man/upsdrvsvcctl.txt support for --timeout-cmd / --timeout-args => Nut driver enumerator optimize #682 (probably)
• docs/nut-names.txt - input.group.color, input.realpower.nominal data points => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• docs/nut-names.txt - input.feed.color, input.feed.desc, outlet.group.n.input, many ambient.* data points => issue Import from FTY branch: "ambient" data point naming #2339
• netxml-ups SSL support => drivers/Makefile.am: snmp and netxml UPSes should have SSL flags/libs… #2479
• apc-iem-mib.h => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• eaton-pdu-marlin-helpers.h/c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• struct init for info_lkp_t and snmp_info_t (varied number of fields) => snmp mib2nut wrapper macros #2285
• drivers/eaton-ats16-nm2-mib.c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/eaton-ats16-nmc-mib.c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/eaton-pdu-marlin-mib.c - many different mappings => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/mge-mib.c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/mge-xml.c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/netxml-ups.c (deci toggle) => actually the FTY part should be dropped, left-over from when the do_convert_deci toggle was converted from boolean setting into a flag checked right in mge-xml.c; will be posted in FTY remerge from master as of 2024-06-15 #2472 resync
• drivers/powerware-mib.c => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• drivers/snmp-ups-helpers.c/h => Upstream Eaton/Powerware/MGE data mappings from 42ity/nut #1319
• check *.pc files (should use @Prefix@, files in 42ity use /usr directly) => FTY remerge from master as of 2024-03-02 #2275 (fix in FTY branch)
• scripts/python/app/NUT-Monitor.in (should use configured path, 42ity uses hardcoded) => solved by one of the resyncs from master... FTY remerge from master as of 2024-03-02 #2275?
• m4/ax_c_pragmas.m4 - HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_PEDANTIC => m4/ax_c_pragmas.m4: introduce HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_ADDRESS and HAVE_PRAGMA_GCC_DIAGNOSTIC_IGNORED_PEDANTIC #2477
• stdbool vs. other bool's (see also NUT issues Consolidate bool_t definitions into a common header file #31 and Refactor code from custom bool_t to stdbool.h (where available) #1176, nut-scanner) => https://github.com/networkupstools/nut/pulls?q=label%3AC-bool - maybe better addressed practically after the merge of FTY branch, holistically for all NUT code base at that time?
• scripts/systemd/* variations => solved by one of the resyncs from master... FTY remerge from master as of 2024-03-02 #2275?
• auglens test data => issue Import from FTY branch: auglenstest bits #2341, PR Define an auglenstestsdir to install the augeas test_nut.aug file #2474
• "reference" packaging (see also NUT issue CI/Packaging: Want packaging recipes and integration with OpenSUSE Build Service (OBS) for master branch #1209)

Notes about known feature changes between the forks (as of comparison in early 2022, before some of these changes got upstreamed in e.g. #320):

• mibs=eaton_epdu
  ** added "device.N.outlet.switchable" fields
  ** renamed the value of "ambient.contacts.N.status" from "opened" to "open"; note they are "opened" in other MIBs as seen below

-ambient.contacts.1.status: opened
+ambient.contacts.1.status: open
+outlet.switchable: yes

** "device.N.input.feed.desc", "device.N.outlet.M.name", separated "device.N.outlet.group.M.name" vs. "device.N.outlet.group.M.desc" (also added "device.N.outlet.switchable")
** NOTE: compared to those master-branch builds, LOST phase info "outlet.group.N.phase" however maybe only for single-phase devices? seems there is a rename for three-phased ones:

### 1ph:
-outlet.group.1.phase: L1
-outlet.group.2.phase: L1

### 3ph:
+outlet.group.1.desc: Section A
-outlet.group.1.name: Section A
-outlet.group.1.phase: L1
+outlet.group.1.name: A
+outlet.group.1.phase: 1-N
+outlet.group.2.desc: Section B
-outlet.group.2.name: Section B
-outlet.group.2.phase: L2
+outlet.group.2.name: B
+outlet.group.2.phase: 2-N
+outlet.group.3.desc: Section C
-outlet.group.3.name: Section C
-outlet.group.3.phase: L3
+outlet.group.3.name: C
+outlet.group.3.phase: 3-N

...and in at least one case for one phase also (but that may be some experimental ePDU? its data dump includes three separate input phase data collections, but just one outlet group... can that be a three-phase outlet actually?):

+input.feed.desc: Feed A
+outlet.1.name: A1
+outlet.group.1.desc: Section A
-outlet.group.1.name: Section A
-outlet.group.1.phase: L1
+outlet.group.1.name: A
+outlet.group.1.phase: 1-N

• mibs=pw
  ** between 42ity/nut versions, iteratively added lots of info categories for ambient sensors; listing some unique-name samples here:

+ambient.1.contacts.1.config: normal-opened
+ambient.1.contacts.1.name: EMPDT1H1C2 @1-C1
+ambient.1.contacts.1.status: inactive
...
+ambient.1.humidity.status: good
+ambient.1.id: d01fd439-a44e-5367-bc99-5b5108c9abc5
+ambient.1.mfr: Eaton
+ambient.1.model: Eaton EMPDT1H1C2
+ambient.1.name: EMPDT1H1C2 @1
+ambient.1.present: no
+ambient.1.serial: GBxxxxxxxx
+ambient.1.temperature.status: good
+ambient.1.temperature.unit: celsius
...
+ambient.contacts.1.name: EMPDT1H1C2 @1-C1
+ambient.contacts.2.name: EMPDT1H1C2 @1-C2

...and "outlet.N.status" and "outlet.switchable" where applicable (UPS):

...
+outlet.1.status: on
+outlet.2.status: on
+outlet.switchable: yes

** compared to upstream, added "ambient.contacts.N.status" status (note "opened" not "open" here, while "ambient.N.contacts.M.status" flip between "active"/"inactive") and changed "ups.type" reading, and added "outlet.N.status" and "outlet.switchable" for UPS:

+ambient.contacts.2.name: EMPDT1H1C2 @1-C2
+ambient.contacts.2.status: opened
+outlet.1.status: on
+outlet.2.status: on
+outlet.switchable: yes
-ups.type: high efficiency
+ups.type: On-Line UPS, Single Phase

• mibs=pxgx_ups
  ** added "ambient.contacts.N.name" and "outlet.N.status"
  ** Compared to master builds (same for 20190711, 20211102_a12302c90ae) added more (note: "opened" not "open"):

+ambient.contacts.1.name: Input \#1
+ambient.contacts.1.status: opened
+ambient.contacts.2.name: Input \#2
+ambient.contacts.2.status: closed
+device.contact: Team
+device.location: Rack
+outlet.1.status: on
+outlet.2.status: on
-ups.type: normal
+ups.type: On-Line UPS, Single Phase

• mibs=mge
  ** Compared to master builds, added "ambient.contacts.N.status" (note: "opened" not "open") and "device.contact"/"device.location":

+ambient.contacts.1.status: opened
+ambient.contacts.2.status: closed
+device.contact: Team
+device.location: Rack

• mibs=ietf
  ** Compared to master builds, added device.contact and device.location like above

Also it would help migrations and refactoring with peace of mind, if the 42ity/nut codebase passed same CI requirements as the upstream NUT. Some notes in this regard:

The work about bug-fixing is quite iterative and "simple" structurally, after all the recent improvements that landed in NUT and its recipes already:

:; git clone -b FTY https://github.com/42ity/nut .
:; BUILD_WARNFATAL=yes BUILD_WARNOPT=medium CANBUILD_DRIVERS_DMF=yes BUILD_TYPE=default-alldrv ./ci_build.sh

...and read the warnings which pop up, fix them, make until the recipe looks okay.

Note how many of these warnings follow some same pattern; it makes sense to address each "family" separately, possibly coming up with some common systemic solution.
In a few cases warnings may be mis-fires from the static analyser in compiler, and pragmas would be used to quiesce them - see precedent to check and define the platform support for particular pragmas and warning options.
In many cases note the mess with integer types - prefer fixed-width types (rather than architecture-dependent int/short/long) and particular signedness following system headers; particularly note e.g. ssize_t (rarely) or size_t (often) for read sizes, array sizes, memory buffer sizes etc. instead of opportunistic int. All this is related to range-checks in many cases, with "tautology" quiesced by pragmas because on some platforms the check is pointless and protects against the other platforms.
Then post a PR to have NUT CI farm go at it, using a hundred combos on different platforms and toolkit versions.
See docs/config-prereq.txt for different platform setup notes, to reproduce faults in local VMs.
Repeat until NUT CI passes green.

Currently known issues fall into just a few buckets:
Helper script _wsum to summarize issues:

#!/bin/sh
date; \
echo "Making whatever succeeds"; \
make -j -k >/dev/null 2>&1; \
echo "Making for error report"; \
make -k > wall.tmp 2>&1 ; \
mv -f wall.tmp wall; \
egrep '\[K?-Werror' < wall > wsum \
&& awk '{print $NF}' < wsum | sort | uniq -c | sort -n > wsum.count \
&& wc -l wsum >> wsum.count \
&& cat wsum.count

Example run:

$ ./_wsum 
February  2, 2022 at 02:58:20 PM CET
Making whatever succeeds
Making for error report
      1 [-Werror=pedantic]
      1 [-Werror=unused-parameter]
     39 [-Werror]
    697 [-Werror=missing-field-initializers]
738 wsum

The few errors above are about definitions:

scan_snmp.c:106:13: error: redefinition of typedef 'bool_t' [-Werror=pedantic]

../../include/config.h:29: error: "BINDIR" redefined [-Werror]
../../include/config.h:32: error: "CGIPATH" redefined [-Werror]
../../include/config.h:35: error: "CONFPATH" redefined [-Werror]
../../include/config.h:47: error: "DATADIR" redefined [-Werror]
../../include/config.h:51: error: "DEFAULT_DMFNUTSCAN_DIR" redefined [-Werror]
../../include/config.h:55: error: "DEFAULT_DMFNUTSCAN_RES_DIR" redefined [-Werror]
../../include/config.h:58: error: "DEFAULT_DMFSNMP_DIR" redefined [-Werror]
../../include/config.h:61: error: "DEFAULT_DMFSNMP_RES_DIR" redefined [-Werror]
../../include/config.h:64: error: "DRVPATH" redefined [-Werror]
../../include/config.h:812: error: "HTMLPATH" redefined [-Werror]
../../include/config.h:815: error: "LIBDIR" redefined [-Werror]
../../include/config.h:818: error: "LIBEXECDIR" redefined [-Werror]
../../include/config.h:914: error: "SBINDIR" redefined [-Werror]

drivers/eaton-pdu-marlin-mib.c:825:42: error: unused parameter 'daisy_dev_list' [-Werror=unused-parameter]

...and a large amount of same error with missing field initializers for snmp_info_t tables (DMF codebase has more fields there, aiming for more conversion function types; if that approach survives - an initialization macro may be due to substitute the NULLs where no value was given).