* runtime,syscall,internal/poll,os: wasip1 poll_oneoff scheduler integration + net.FileListener
On wasip1 today every syscall.Read/Write blocks the entire wasm module — the
cooperative scheduler invokes poll_oneoff only for sleep/timer wakeups, and
there's no path from the net package to a working TCP server. This change
fixes both: it threads poll_oneoff through the scheduler's idle path so a
goroutine doing FD I/O parks instead of blocking the module, and it provides
enough internal/poll / os / syscall surface that upstream Go's
net.FileListener / net.FileConn works on a host-pre-opened TCP socket.
* runtime: keep scheduler_cooperative idle-wait calls direct
TestBinarySize/hifive1b/examples/echo regressed by 32 bytes after the
previous commit routed the scheduler's idle wait through a
schedulerIdleWait helper. The extra call frame + branch landed on every
non-wasip1 cooperative target, where the original direct sleepTicks /
waitForEvents calls compile to a single inlined call.
This commit changes signal handling in a few ways:
* It stubs signals for all wasm targets (not just wasi) and baremetal,
since none of those have traditional POSIX signals. And moves the
code for that into a single file, instead of duplicating it.
* It removes the stub for signal_ignored since the value `false` might
be wrong in some cases and it doesn't usually seem to be called (it
is not called in tsgo). Should be trivial to re-add if it is shown
to be needed.
* It adds a stub for `os/signal.signalWaitUntilIdle` which _is_ called
by tsgo.
This adds support for the `//go:wasmexport` pragma as proposed here:
https://github.com/golang/go/issues/65199
It is currently implemented only for wasip1 and wasm-unknown, but it is
certainly possible to extend it to other targets like GOOS=js and
wasip2.
This eliminates the 'wasi' build tag in favor of 'GOOS=wasip1', introduced in Go 1.21.
For backwards compatablity, -target=wasi is a synonym for -target=wasip1.
Ayke van Laethem
Achille
Damian Gryski
Randy Reddig