Add support for parsing vintf manifests and matrices

src/blobs/vintf.ts

@@ -0,0 +1,91 @@
+import { promises as fs } from 'fs'
+import * as xml2js from 'xml2js'
+
+import { exists } from '../util/fs'
+import { EXT_PARTITIONS } from '../util/partitions'
+
+const XML_BUILDER = new xml2js.Builder({
+  xmldec: {
+    version: '1.0',
+  },
+})
+
+// Very ugly, but this is just the raw parsed XML format
+export interface VintfHal {
+  $: {
+    format: string
+    optional?: string
+  }
+  name: Array<string>
+  transport: Array<string>
+  version?: Array<string>
+  interface: Array<{
+    name: Array<string>
+    instance: Array<string>
+  }>
+  fqname?: Array<string>
+}
+
+export interface VintfInfo {
+  manifest: Array<VintfHal> | null
+  matrix: Array<VintfHal> | null
+}
+
+export type PartitionVintfInfo = Map<string, VintfInfo>
+
+function halToKey(hal: VintfHal) {
+  return JSON.stringify(hal)
+}
+
+export function getHalFqNames(hals: Array<VintfHal>) {
+  return hals.flatMap(h => h.fqname?.map(suffix => h.name + suffix) ?? [])
+}
+
+export async function parseVintfManifest(manifestXml: string) {
+  let doc = await xml2js.parseStringPromise(manifestXml)
+  let hals = doc.manifest?.hal ?? doc['compatibility-matrix']?.hal ?? []
+  return hals as Array<VintfHal>
+}
+
+export async function loadVintfManifest(root: string, partition: string, name: string = 'manifest') {
+  let path = `${root}/${partition}/etc/vintf/${name}.xml`
+  if (!(await exists(path))) {
+    return null
+  }
+
+  let xml = await fs.readFile(path, { encoding: 'utf8' })
+  return parseVintfManifest(xml)
+}
+
+export async function loadPartVintfInfo(root: string) {
+  let partInfo: PartitionVintfInfo = new Map<string, VintfInfo>()
+  for (let partition of EXT_PARTITIONS) {
+    let manifest = await loadVintfManifest(root, partition, 'manifest')
+    let matrix = await loadVintfManifest(root, partition, 'compatibility_matrix')
+    if (manifest != null || matrix != null) {
+      partInfo.set(partition, {
+        manifest: manifest,
+        matrix: matrix,
+      })
+    }
+  }
+
+  return partInfo
+}
+
+export function diffVintfHals(halsRef: Array<VintfHal>, halsNew: Array<VintfHal>) {
+  let refKeys = new Set(halsRef.map(halToKey))
+  return halsNew.filter(h => !refKeys.has(halToKey(h)))
+}
+
+export function serializeVintfHals(hals: Array<VintfHal>) {
+  return XML_BUILDER.buildObject({
+    manifest: {
+      $: {
+        version: '1.0',
+        type: 'device',
+      },
+      hal: hals,
+    }
+  })
+}