Migrate eventfd to socketpair to support macOS

[LasseRosenow]

Fixes #176

[github-actions]

Memory usage after merging this PR will be:

Memory Report

action_empty_test_c

	from	to	increase (%)
text	59715	59715	0.00
data	744	744	0.00
bss	10112	10112	0.00
total	70571	70571	0.00

action_microstep_test_c

	from	to	increase (%)
text	60586	60586	0.00
data	752	752	0.00
bss	10112	10112	0.00
total	71450	71450	0.00

action_overwrite_test_c

	from	to	increase (%)
text	60423	60423	0.00
data	744	744	0.00
bss	10112	10112	0.00
total	71279	71279	0.00

action_test_c

	from	to	increase (%)
text	60327	60327	0.00
data	752	752	0.00
bss	10112	10112	0.00
total	71191	71191	0.00

deadline_test_c

	from	to	increase (%)
text	55913	55913	0.00
data	760	760	0.00
bss	10784	10784	0.00
total	67457	67457	0.00

delayed_conn_test_c

	from	to	increase (%)
text	61342	61342	0.00
data	744	744	0.00
bss	10112	10112	0.00
total	72198	72198	0.00

event_payload_pool_test_c

	from	to	increase (%)
text	18330	18330	0.00
data	624	624	0.00
bss	320	320	0.00
total	19274	19274	0.00

event_queue_test_c

	from	to	increase (%)
text	27597	27597	0.00
data	736	736	0.00
bss	480	480	0.00
total	28813	28813	0.00

nanopb_test_c

	from	to	increase (%)
text	42888	42888	0.00
data	904	904	0.00
bss	320	320	0.00
total	44112	44112	0.00

port_test_c

	from	to	increase (%)
text	61290	61290	0.00
data	744	744	0.00
bss	10112	10112	0.00
total	72146	72146	0.00

reaction_queue_test_c

	from	to	increase (%)
text	27319	27319	0.00
data	736	736	0.00
bss	480	480	0.00
total	28535	28535	0.00

request_shutdown_test_c

	from	to	increase (%)
text	60558	60558	0.00
data	744	744	0.00
bss	10112	10112	0.00
total	71414	71414	0.00

startup_test_c

	from	to	increase (%)
text	55612	55612	0.00
data	752	752	0.00
bss	10784	10784	0.00
total	67148	67148	0.00

tcp_channel_test_c

	from	to	increase (%)
text	93837	93846	0.01
data	1224	1224	0.00
bss	21280	21312	0.15
total	116341	116382	0.04

timer_test_c

	from	to	increase (%)
text	55503	55503	0.00
data	744	744	0.00
bss	10784	10784	0.00
total	67031	67031	0.00

[github-actions]

Benchmark results after merging this PR:

Benchmark results

Performance:

PingPongUc:
Best Time: 134.356 msec
Worst Time: 141.492 msec
Median Time: 134.357 msec

PingPongC:
Best Time: 169.910 msec
Worst Time: 177.058 msec
Median Time: 170.121 msec

ReactionLatencyUc:
Best latency: 41099 nsec
Median latency: 59871 nsec
Worst latency: 118774 nsec

ReactionLatencyC:
Best latency: 39814 nsec
Median latency: 60283 nsec
Worst latency: 97917 nsec

Memory usage:

PingPongUc:
text data bss dec hex filename
39564 752 8496 48812 beac bin/PingPongUc

PingPongC:
text data bss dec hex filename
46044 872 360 47276 b8ac bin/PingPongC

ReactionLatencyUc:
text data bss dec hex filename
29689 736 2112 32537 7f19 bin/ReactionLatencyUc

ReactionLatencyC:
text data bss dec hex filename
41666 840 360 42866 a772 bin/ReactionLatencyC

[github-actions]

Coverage after merging migrate-eventfd-to-socketpairs into main will be

71.19%

Coverage Report

File	Stmts	Branches	Funcs	Lines	Uncovered Lines
src
action.c	77.69%	65.63%	100%	81.18%	134–135, 24, 42–45, 48, 50–51, 54–56, 62–63, 70–72, 72, 72–75, 81–82, 93–94
builtin_triggers.c	90.91%	70%	100%	96.77%	14, 18, 40, 43
connection.c	78.52%	51.16%	100%	88.66%	10, 104, 11, 110, 123–124, 136–137, 14, 14, 143, 145, 16–17, 21–22, 22, 22–23, 25, 27–28, 33, 48, 48, 48–49, 55, 60–62, 97
environment.c	78.35%	55.56%	84.62%	83.33%	12–13, 18, 20–21, 31, 35–36, 42–43, 51–52, 55–56, 60–61, 93–95
event.c	95.35%	92.86%	100%	96.15%	14–15
federated.c	5.61%	2.97%	7.69%	6.76%	101, 104–105, 105, 105–106, 108–109, 11, 111, 115–116, 118–120, 123, 125–129, 13, 13, 13, 130, 132–134, 137–139, 139, 139, 14, 140, 140, 140–142, 144, 147–148, 15, 150–154, 156–159, 16, 160–161, 163, 163, 163–166, 168, 168, 168–169, 17, 17, 17, 170, 170, 170–171, 175–176, 176, 176, 179–180, 184–186, 188, 188, 188, 190–194, 197, 197, 197–199, 20, 200, 203–204, 204, 204–205, 207–208, 21, 211–212, 217–218, 218, 218–219, 22, 22, 22, 221, 223, 223, 223–226, 226, 226, 226, 226–229, 23, 230–238, 24, 24, 24, 242, 245, 245, 245–247, 25, 251, 254–255, 255, 255, 255–259, 26, 260–263, 265, 27, 27, 27, 271–273, 28, 28, 28, 28, 28, 285–286, 289, 29, 290–292, 294, 294, 294–295, 299–300, 300, 300, 302, 304–305, 305, 305–306, 306, 306–307, 307, 307–308, 308, 308–309, 309, 309, 31, 310, 310, 310, 312, 312, 312–313, 313, 313–314, 314, 314–315, 315, 315, 317, 34, 34, 34, 34, 34–35, 38, 42–43, 45–48, 50, 50, 50–51, 51, 51, 53, 53, 53–55, 55, 55–57, 61–62, 66–67, 69–72, 74, 76, 76, 76–77, 77, 77–78, 78, 78–79, 79, 79, 82–83, 85–88, 9, 90, 90, 90–93, 95, 97, 97, 97–98
logging.c	87.50%	80%	100%	88.64%	24, 37–39, 46, 59–60
network_channel.c	57.69%	50%	100%	58.82%	36, 36, 36, 36, 41–44, 49–50, 53
port.c	78.08%	45.83%	100%	93.33%	10, 10, 10, 16, 20, 25, 25–27, 27, 27–28, 39, 39, 39–40
queues.c	89.94%	80.36%	100%	94.06%	108, 113, 119, 21–23, 47–48, 60–61, 84–88, 91–92
reaction.c	70.34%	54.55%	100%	78.26%	15, 17, 21–22, 28–31, 31, 31–32, 42, 45, 47, 52–53, 53, 53–55, 55, 55–56, 73, 89–91, 91, 91–94, 94, 94–95
reactor.c	69.33%	51.52%	100%	82.28%	10, 101–102, 14–19, 22, 28, 30, 32–37, 37, 37–38, 38, 38, 43, 55, 58–59, 59, 59–60, 60, 60–61, 63, 77–78, 81–82, 82, 82–83, 83, 83–84, 86, 91
serialization.c	50%	50%	50%	50%	16–17, 26–27, 33–35, 38–40
tag.c	40.19%	31.48%	60%	47.92%	14, 14–15, 17, 17–18, 23–24, 24, 24, 24, 24–25, 27, 27, 27, 27, 27–28, 30, 30, 30–31, 33–34, 34, 34–35, 37, 37, 37, 37, 37–38, 40, 40, 40, 40, 40–41, 43, 53–54, 63, 63–64, 83–85, 85, 85, 85, 85, 85, 85, 85, 85, 85, 85–87, 89
timer.c	95%	66.67%	100%	100%	14, 25
trigger.c	100%	100%	100%	100%
util.c	0%	0%	0%	0%	10, 3–4, 4, 4–5, 5, 5–6, 8–9
src/platform/posix
posix.c	52.73%	30%	66.67%	56%	100, 100, 100–102, 106, 16, 18, 20–21, 34–36, 38–40, 48–49, 54–59, 59, 59–62, 62, 62–64, 67, 73–74, 78, 81, 92–94, 94, 94–96, 98–99
tcp_ip_channel.c	66.41%	51.61%	100%	75.99%	100, 102, 105–106, 116–117, 117, 117–118, 123–124, 124, 124–126, 130–131, 131, 131–133, 147, 153, 153, 153, 153, 153–154, 154, 154–155, 157, 157, 157–158, 167, 174–175, 179, 183, 183, 183–185, 185, 185–186, 188, 188, 188–190, 194, 194, 194–195, 215, 228–229, 229, 229–230, 236, 241–242, 242, 242–243, 243, 243–244, 246–247, 247, 247–248, 248, 248, 250–253, 263, 263–264, 264, 264–265, 289–290, 290, 290–292, 292, 292–293, 293, 293–294, 303, 303, 308, 310, 312, 314, 326–327,

[tanneberger]

does eventfd_write really write an "X" ?

[LasseRosenow]

Actually it doesn't matter what you write you just need to write something and x is just one byte

[erlingrj]

Thanks for addressing this so quickly, it looks good to me!