Merge pull request #293 from dscho/make-/dev/fd/-work

Ensure that /dev/fd/ & friends exist

Author: dscho

.github/workflows/test.yml

@@ -61,3 +61,6 @@ jobs:
 
           # Verify that the locale is set, enabling `grep -P` to work
           test 123 = "$(printf '1248\n123\n' | grep -P '2(?!4)')"
+
+          # Verify that /dev/fd/<pid> works
+          test hello = "$(cat <(echo hello))"

.vscode/settings.json

@@ -10,13 +10,15 @@
         "vstfs://.*"
     ],
     "cSpell.words": [
+        "artifactsize",
+        "autodrain",
         "Backoff",
+        "mqueue",
         "MSYSTEM",
         "Pacman",
-        "artifactsize",
-        "autodrain",
         "unzipper",
-        "vercel"
+        "vercel",
+        "winsymlinks"
     ],
     "git.ignoreLimitWarning": true
 }

__tests__/main.test.ts

@@ -58,5 +58,15 @@ if (process.env.RUN_NETWORK_TESTS !== 'true') {
     expect(
       statSync.bind(null, `${outputDirectory}/mingw64/bin/gcc.exe`)
     ).not.toThrow()
+
+    const hello = child_process.spawnSync(
+      'usr\\bin\\bash.exe',
+      ['-lc', 'cat <(echo hello)'],
+      {
+        cwd: outputDirectory
+      }
+    )
+    expect(hello.stderr.toString()).toBe('')
+    expect(hello.stdout.toString()).toBe('hello\n')
   })
 }

dist/index.js

@@ -1,7 +1,8 @@
 import * as core from '@actions/core'
+import {get, mkdirp} from './src/downloader'
 import {restoreCache, saveCache} from '@actions/cache'
-import {get} from './src/downloader'
 import process from 'process'
+import {spawnSync} from 'child_process'
 
 async function run(): Promise<void> {
   try {
@@ -80,6 +81,29 @@ async function run(): Promise<void> {
     ) {
       core.exportVariable('LC_CTYPE', 'C.UTF-8')
     }
+
+    // ensure that /dev/fd/*, /dev/mqueue and friends exist
+    for (const path of ['/dev/mqueue', '/dev/shm']) {
+      mkdirp(`${outputDirectory}${path}`)
+    }
+
+    const ln = (linkPath: string, target: string): void => {
+      const child = spawnSync('ln.exe', ['-s', target, linkPath], {
+        cwd: outputDirectory,
+        env: {
+          MSYS: 'winsymlinks:sys'
+        }
+      })
+      if (child.error) throw child.error
+    }
+    for (const [linkPath, target] of Object.entries({
+      fd: 'fd',
+      stdin: 'fd/0',
+      stdout: 'fd/1',
+      stderr: 'fd/2'
+    })) {
+      ln(`/dev/${linkPath}`, `/proc/self/${target}`)
+    }
   } catch (error) {
     core.setFailed(error instanceof Error ? error.message : `${error}`)
   }

dist/index.js.map

@@ -19,7 +19,7 @@ async function fetchJSONFromURL<T>(url: string): Promise<T> {
   return (await res.json()) as T
 }
 
-function mkdirp(directoryPath: string): void {
+export function mkdirp(directoryPath: string): void {
   try {
     const stat = fs.statSync(directoryPath)
     if (stat.isDirectory()) {