feat(win32)!: allow install and just no-op unsupported operations (#288)

* feat: allow windows installs

all the methods are no-op on windows always returning false

* feat: run actions on windows

* chore: update docs

* feat!: guard against nullish descriptors

.github/workflows/pull-request.yaml

@@ -69,6 +69,7 @@ jobs:
         os:
           - ubuntu-latest
           - macos-latest
+          - windows-latest
         node: # https://nodejs.org/en/about/releases/
           - '*' # Current
           - '14' # Active LTS

.github/workflows/release.yaml

@@ -13,6 +13,7 @@ jobs:
         os:
           - ubuntu-latest
           - macos-latest
+          - windows-latest
         node: # https://nodejs.org/en/about/releases/
           - '*' # Current
           - '14' # Active LTS

README.md

@@ -32,7 +32,8 @@
 
 The Missing (`TCP_KEEPINTVL` and `TCP_KEEPCNT`) `SO_KEEPALIVE` socket option setters and getters for Node using [`ffi-napi`](https://www.npmjs.com/package/ffi-napi) module.
 
-Tested on 🐧 `linux` & 🍏 `osx` (both `amd64` and `arm64`), should work on 😈 `freebsd` and others. Does not work on 🐄 `win32` (pull requests welcome).
+Tested on 🐧 `linux` & 🍏 `osx` (both `amd64` and `arm64`), should work on 😈 `freebsd` and others. 
+Installs on 🐄 `win32` 🎉 but methods are no-ops (pull requests welcome).
 
 There's also support for getting & setting the `TCP_USER_TIMEOUT` (🐧 `linux`  and 🍏 `osx` only) option, which is closely related to keep-alive.
 
@@ -44,11 +45,12 @@ There's also support for getting & setting the `TCP_USER_TIMEOUT` (🐧 `linux`
 | 🐧 `linux`   | ✅            | ✅          | ✅                          |
 | 🍏 `osx`     | ✅            | ✅          | ✅ (`TCP_RXT_CONNDROPTIME`) |
 | 😈 `freebsd` | ✅            | ✅          | ❌                          |
-| 🐄 `win32`   | ❌            | ❌          | ❌                          |
+| 🐄 `win32`   | ➖            | ➖          | ➖                          |
 
 Legend:
 
 - ✅ - Supported
+- ➖ - No operation 
 - ❌ - Unsupported (throws)
 
 ## Install

lib/ffi-bindings.js

@@ -1,40 +1,65 @@
-'use strict'
+const { platform } = require('os')
+const { errnoException } = require('./commons')
+const Ref = require('ref-napi')
+const FFI = require('ffi-napi')
 
-const Ref = require('ref-napi'),
-  FFI = require('ffi-napi'),
-  Commons = require('./commons')
+const createFFI = () => {
+  const cInt = Ref.types.int
+  const cVoid = Ref.types.void
 
-const cInt = Ref.types.int,
-  cVoid = Ref.types.void
+  return FFI.Library(null, {
+    //name       ret    1     2     3     4                   5
+    setsockopt: [cInt, [cInt, cInt, cInt, Ref.refType(cVoid), cInt]],
+    getsockopt: [
+      cInt,
+      [cInt, cInt, cInt, Ref.refType(cVoid), Ref.refType(cInt)],
+    ],
+  })
+}
 
-const ffi = FFI.Library(null, {
-  //name       ret    1     2     3     4                   5
-  setsockopt: [cInt, [cInt, cInt, cInt, Ref.refType(cVoid), cInt]],
-  getsockopt: [cInt, [cInt, cInt, cInt, Ref.refType(cVoid), Ref.refType(cInt)]],
-})
+const ffi = (() => {
+  let instance
+  return () => {
+    if (!instance) {
+      instance = createFFI()
+    }
+    return instance
+  }
+})()
 
 const setsockopt = (fd, level, name, value, valueLength) => {
-  const err = ffi.setsockopt(fd, level, name, value, valueLength)
+  if(fd == null) {
+    return false
+  }
+
+  const err = ffi().setsockopt(fd, level, name, value, valueLength)
 
   if (err !== 0) {
-    let errno = FFI.errno()
-    throw Commons.errnoException(errno, 'setsockopt')
+    const errno = FFI.errno()
+    throw errnoException(errno, 'setsockopt')
   }
 
   return true
 }
 
 const getsockopt = (fd, level, name, value, valueLength) => {
-  const err = ffi.getsockopt(fd, level, name, value, valueLength)
+  if(fd == null) {
+    return false
+  }
+
+  const err = ffi().getsockopt(fd, level, name, value, valueLength)
 
   if (err !== 0) {
-    let errno = FFI.errno()
-    throw Commons.errnoException(errno, 'getsockopt')
+    const errno = FFI.errno()
+    throw errnoException(errno, 'getsockopt')
   }
   return true
 }
 
+const noop = () => false
+const isWin32 = platform() === 'win32'
+
 module.exports = {
-  setsockopt,
-  getsockopt,
+  setsockopt: isWin32 ? noop : setsockopt,
+  getsockopt: isWin32 ? noop : getsockopt,
 }

lib/index.js

@@ -20,6 +20,7 @@
 
 const Assert = require('assert'),
   Net = require('net'),
+  OS = require('os'),
   Constants = require('./constants'),
   Ref = require('ref-napi'),
   FFIBindings = require('./ffi-bindings')
@@ -28,7 +29,9 @@ const _isSocket = (socket) => socket instanceof Net.Socket
 
 const _getSocketFD = (socket) => {
   const fd = socket._handle != null ? socket._handle.fd : undefined
-  Assert(fd && fd !== -1, 'Unable to get socket fd')
+  if (OS.platform() !== 'win32') {
+    Assert(fd && fd !== -1, 'Unable to get socket fd')
+  }
   return fd
 }