std.Io.net: enable more tests + coverage for canceling accept #31468

If any of these fail let's try to diagnose them.

closes #18315
closes #25983
closes #31388

+ stage3-debug/bin/zig build --prefix stage4-debug -Denable-llvm -Dno-lib -Dtarget=x86_64-linux-musl -Duse-zig-libcxx -Dversion-string=0.16.0-dev.2864+28abe1d74
+ stage4-debug/bin/zig test ../test/behavior.zig
General protection exception (no address available)
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/std/mem.zig:781:42: 0x1aebf76 in eqlBytes (std.zig)
 x |= @as(u32, @bitCast(a[n..][0..4].*)) ^ @as(u32, @bitCast(b[n..][0..4].*));
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/std/mem.zig:736:24: 0x1aeb6ee in eql__anon_13712 (std.zig)
 return eqlBytes(sliceAsBytes(a), sliceAsBytes(b));
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/test/behavior/nan.zig:37:31: 0x138847d9 in test.nan memory equality (behavior.zig)
 try testing.expect(mem.eql(u8, mem.asBytes(&qnan_u32), mem.asBytes(&qnan_f32)));
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/compiler/test_runner.zig:255:25: 0x1bf4786 in mainTerminal (test_runner.zig)
 if (test_fn.func()) |_| {
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/compiler/test_runner.zig:70:28: 0x1bf3fa2 in main (test_runner.zig)
 return mainTerminal(init);
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/std/start.zig:678:88: 0x1bf0886 in callMain (std.zig)
 if (fn_info.params[0].type.? == std.process.Init.Minimal) return wrapMain(root.main(.{
 ^
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/lib/std/start.zig:190:5: 0x1bf0291 in _start (std.zig)
 asm volatile (switch (native_arch) {
 ^
error: the following test command terminated with signal ABRT:
/home/ci/.cache/act/6f223879ad80ff37/hostexecutor/zig-local-cache/o/1c1763fdacdc42b2c5985027022cb2bb/test --seed=0x12613d8f

hm the AlertableSyscall strategy did not fix cancelation:

test
+- test-modules
 +- test-std
 +- run test std-native-znver5-ReleaseSafe 3014 pass, 64 skip, 1 timeout (3079 total)
error: 'Io.net.test.test.cancel accept' timed out after 30m4.99ms
failed command: "C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache\\o\\c93adc2bdb4aac2d08b840f1a213ddd2\\test.exe" "--cache-dir=C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache" --seed=0x85c100da --listen=-
test
+- test-modules
 +- test-std
 +- run test std-native-znver5-Debug 3014 pass, 64 skip, 1 timeout (3079 total)
error: 'Io.net.test.test.cancel accept' timed out after 30m2.755ms
failed command: "C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache\\o\8円cf580ef2ce375b7efc00bdab819bde3\\test.exe" "--cache-dir=C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache" --seed=0x85c100da --listen=-
test
+- test-modules
 +- test-std
 +- run test std-native-znver5-Debug-libc 3014 pass, 64 skip, 1 timeout (3079 total)
error: 'Io.net.test.test.cancel accept' timed out after 30m8.211ms
failed command: "C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache\\o\\d24e21bd74e49a5de8c8b50fc0c7a945\\test.exe" "--cache-dir=C:\\Users\\ci\\.cache\\act\8円d01ce3895aa14a5\\hostexecutor\\zig-local-cache" --seed=0x85c100da --listen=-

Replying to @mlugg:

Ah, sorry, I think you misunderstood me before: the fix isn't this trivial, we will still need to do the same thing as in other overlapped code paths where we set a completion APC and use an alertable wait. Actually, thinking about it, I'm not entirely sure if you can actually set an APC for ws2_32 stuff, so maybe this is a bit trickier? (I don't have docs open right now, on mobile.) I'll take a look at this later today so I can at least confirm what you could do.

I think these are the two options:

• use LPOVERLAPPED with ws2_32 operations and add additional cancel mechanism that calls CancelIoEx which needs both the HANDLE and pointer to LPOVERLAPPED operation to cancel.
• start using \Device\Afd directly (against advice of #31131)