feat: support libc field checks (#54)

Author: nlf

README.md

@@ -11,8 +11,7 @@ Errors have a `required` and `current` fields.
 
 ### .checkEngine(pkg, npmVer, nodeVer, force = false)
 
-Check if node/npm version is supported by the package. If it isn't
-supported, an error is thrown.
+Check if a package's `engines.node` and `engines.npm` match the running system.
 
 `force` argument will override the node version check, but not the npm
 version check, as this typically would indicate that the current version of
@@ -22,6 +21,8 @@ Error code: 'EBADENGINE'
 
 ### .checkPlatform(pkg, force)
 
-Check if OS/Arch is supported by the package.
+Check if a package's `os`, `cpu` and `libc` match the running system.
+
+`force` argument skips all checks.
 
 Error code: 'EBADPLATFORM'

lib/index.js

@@ -20,6 +20,8 @@ const checkEngine = (target, npmVer, nodeVer, force = false) => {
   }
 }
 
+const isMusl = (file) => file.includes('libc.musl-') || file.includes('ld-musl-')
+
 const checkPlatform = (target, force = false) => {
   if (force) {
     return
@@ -30,16 +32,35 @@ const checkPlatform = (target, force = false) => {
   const osOk = target.os ? checkList(platform, target.os) : true
   const cpuOk = target.cpu ? checkList(arch, target.cpu) : true
 
-  if (!osOk || !cpuOk) {
+  let libcOk = true
+  let libcFamily = null
+  if (target.libc) {
+    // libc checks only work in linux, any value is a failure if we aren't
+    if (platform !== 'linux') {
+      libcOk = false
+    } else {
+      const report = process.report.getReport()
+      if (report.header?.glibcRuntimeVersion) {
+        libcFamily = 'glibc'
+      } else if (Array.isArray(report.sharedObjects) && report.sharedObjects.some(isMusl)) {
+        libcFamily = 'musl'
+      }
+      libcOk = libcFamily ? checkList(libcFamily, target.libc) : false
+    }
+  }
+
+  if (!osOk || !cpuOk || !libcOk) {
     throw Object.assign(new Error('Unsupported platform'), {
       pkgid: target._id,
       current: {
         os: platform,
         cpu: arch,
+        libc: libcFamily,
       },
       required: {
         os: target.os,
         cpu: target.cpu,
+        libc: target.libc,
       },
       code: 'EBADPLATFORM',
     })

test/check-platform.js

@@ -42,3 +42,81 @@ t.test('os wrong (negation)', async t =>
 
 t.test('nothing wrong (negation)', async t =>
   checkPlatform({ cpu: '!enten-cpu', os: '!enten-os' }))
+
+t.test('libc', (t) => {
+  let PLATFORM = ''
+
+  const _processPlatform = Object.getOwnPropertyDescriptor(process, 'platform')
+  Object.defineProperty(process, 'platform', {
+    enumerable: true,
+    configurable: true,
+    get: () => PLATFORM,
+  })
+
+  let REPORT = {}
+  const _processReport = process.report.getReport
+  process.report.getReport = () => REPORT
+
+  t.teardown(() => {
+    Object.defineProperty(process, 'platform', _processPlatform)
+    process.report.getReport = _processReport
+  })
+
+  t.test('fails when not in linux', (t) => {
+    PLATFORM = 'darwin'
+
+    t.throws(() => checkPlatform({ libc: 'glibc' }), { code: 'EBADPLATFORM' },
+      'fails for glibc when not in linux')
+    t.throws(() => checkPlatform({ libc: 'musl' }), { code: 'EBADPLATFORM' },
+      'fails for musl when not in linux')
+    t.end()
+  })
+
+  t.test('glibc', (t) => {
+    PLATFORM = 'linux'
+
+    REPORT = {}
+    t.throws(() => checkPlatform({ libc: 'glibc' }), { code: 'EBADPLATFORM' },
+      'fails when report is missing header property')
+
+    REPORT = { header: {} }
+    t.throws(() => checkPlatform({ libc: 'glibc' }), { code: 'EBADPLATFORM' },
+      'fails when header is missing glibcRuntimeVersion property')
+
+    REPORT = { header: { glibcRuntimeVersion: '1' } }
+    t.doesNotThrow(() => checkPlatform({ libc: 'glibc' }), 'allows glibc on glibc')
+    t.throws(() => checkPlatform({ libc: 'musl' }), { code: 'EBADPLATFORM' },
+      'does not allow musl on glibc')
+
+    t.end()
+  })
+
+  t.test('musl', (t) => {
+    PLATFORM = 'linux'
+
+    REPORT = {}
+    t.throws(() => checkPlatform({ libc: 'musl' }), { code: 'EBADPLATFORM' },
+      'fails when report is missing sharedObjects property')
+
+    REPORT = { sharedObjects: {} }
+    t.throws(() => checkPlatform({ libc: 'musl' }), { code: 'EBADPLATFORM' },
+      'fails when sharedObjects property is not an array')
+
+    REPORT = { sharedObjects: [] }
+    t.throws(() => checkPlatform({ libc: 'musl' }), { code: 'EBADPLATFORM' },
+      'fails when sharedObjects does not contain musl')
+
+    REPORT = { sharedObjects: ['ld-musl-foo'] }
+    t.doesNotThrow(() => checkPlatform({ libc: 'musl' }), 'allows musl on musl as ld-musl-')
+
+    REPORT = { sharedObjects: ['libc.musl-'] }
+    t.doesNotThrow(() => checkPlatform({ libc: 'musl' }), 'allows musl on musl as libc.musl-')
+
+    t.throws(() => checkPlatform({ libc: 'glibc' }), { code: 'EBADPLATFORM' },
+      'does not allow glibc on musl')
+
+    t.end()
+  })
+
+  t.end()
+})