Hash native libraries (#8)

This PR changes the way native libraries are enumerated in the ResourceInformation.json file. Previously, we used a list of filenames. We now use a map of filenames:MD5_hash. This allows us to check the hashes of native libraries as they're extracted.

Author: samfreund

.github/workflows/ci.yml

@@ -3,6 +3,17 @@ name: CI
 on: [push, pull_request]
 
 jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v6
+    - uses: actions/setup-java@v5
+      with:
+        java-version: 17
+        distribution: 'temurin'
+    - name: Check for changes
+      run: ./gradlew spotlessCheck
+
   build:
     strategy:
       matrix:

src/main/java/org/photonvision/tools/HashNativeResources.java

@@ -1,20 +1,22 @@
 package org.photonvision.tools;
 
 import com.google.gson.GsonBuilder;
+import java.io.BufferedInputStream;
 import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
+import java.io.OutputStream;
 import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.security.DigestInputStream;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
-import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HexFormat;
 import java.util.List;
 import java.util.Map;
 import javax.inject.Inject;
-import org.codehaus.groovy.runtime.EncodingGroovyMethods;
 import org.gradle.api.DefaultTask;
 import org.gradle.api.file.Directory;
 import org.gradle.api.file.DirectoryProperty;
@@ -26,6 +28,28 @@
 import org.gradle.api.tasks.TaskAction;
 
 public class HashNativeResources extends DefaultTask {
+
+    /**
+     * Architecture-specific information containing file hashes for a specific CPU architecture (e.g.,
+     * x86-64, arm64).
+     */
+    public record ArchInfo(Map<String, String> fileHashes) {}
+
+    /**
+     * Platform-specific information containing architectures for a specific OS platform (e.g., linux,
+     * windows).
+     */
+    public record PlatformInfo(Map<String, ArchInfo> architectures) {}
+
+    /** Overall resource information to be serialized */
+    public record ResourceInformation(
+            // Combined MD5 hash of all native resource files
+            String hash,
+            // Platform-specific native libraries organized by platform then architecture
+            Map<String, PlatformInfo> platforms,
+            // List of supported versions for these native resources
+            List<String> versions) {}
+
     private final DirectoryProperty inputDirectory;
     private final RegularFileProperty hashFile;
     private final RegularFileProperty versionsInput;
@@ -55,16 +79,13 @@ public HashNativeResources() {
 
     @TaskAction
     public void execute() throws NoSuchAlgorithmException, IOException {
-        MessageDigest hash = MessageDigest.getInstance("MD5");
+        MessageDigest combinedHash = MessageDigest.getInstance("MD5");
 
         Directory directory = inputDirectory.get();
 
         Path inputPath = directory.getAsFile().toPath();
 
-        Map<String, Object> platforms = new HashMap<>();
-
-        byte[] buffer = new byte[0xFFFF];
-        int readBytes = 0;
+        Map<String, PlatformInfo> platforms = new HashMap<>();
 
         for (File file : directory.getAsFileTree()) {
             if (!file.isFile()) {
@@ -73,44 +94,49 @@ public void execute() throws NoSuchAlgorithmException, IOException {
 
             Path path = inputPath.relativize(file.toPath());
 
-            try (FileInputStream is = new FileInputStream(file)) {
-                while ((readBytes = is.read(buffer)) != -1) {
-                    hash.update(buffer, 0, readBytes);
-                }
+            // Compute individual file hash
+            MessageDigest fileHash = MessageDigest.getInstance("MD5");
+            try (var dis =
+                    new DigestInputStream(
+                            new DigestInputStream(new BufferedInputStream(new FileInputStream(file)), fileHash),
+                            combinedHash)) {
+                dis.transferTo(OutputStream.nullOutputStream());
             }
 
             String platform = path.getName(0).toString();
             String arch = path.getName(1).toString();
 
             String strPath = "/" + path.toString().replace("\\", "/");
-
-            @SuppressWarnings("unchecked") // This will always be the correct type
-            Map<String, List<String>> platformMap = (Map<String, List<String>>) platforms.get(platform);
-            if (platformMap == null) {
-                platformMap = new HashMap<>();
-                List<String> archFiles = new ArrayList<>();
-                archFiles.add(strPath);
-                platformMap.put(arch, archFiles);
-                platforms.put(platform, platformMap);
+            String hexFileHash = HexFormat.of().formatHex(fileHash.digest());
+
+            PlatformInfo platformInfo = platforms.get(platform);
+            if (platformInfo == null) {
+                Map<String, String> fileHashes = new HashMap<>();
+                fileHashes.put(strPath, hexFileHash);
+                Map<String, ArchInfo> architectures = new HashMap<>();
+                architectures.put(arch, new ArchInfo(fileHashes));
+                platforms.put(platform, new PlatformInfo(architectures));
             } else {
-                List<String> archFiles = platformMap.get(arch);
-                if (archFiles == null) {
-                    archFiles = new ArrayList<>();
-                    archFiles.add(strPath);
-                    platformMap.put(arch, archFiles);
+                Map<String, ArchInfo> architectures = platformInfo.architectures();
+                ArchInfo archInfo = architectures.get(arch);
+                if (archInfo == null) {
+                    Map<String, String> fileHashes = new HashMap<>();
+                    fileHashes.put(strPath, hexFileHash);
+                    architectures.put(arch, new ArchInfo(fileHashes));
                 } else {
-                    archFiles.add(strPath);
+                    archInfo.fileHashes().put(strPath, hexFileHash);
                 }
             }
         }
 
-        var versions = Files.readAllLines(versionsInput.get().getAsFile().toPath());
+        String hash = HexFormat.of().formatHex(combinedHash.digest());
+
+        List<String> versions = Files.readAllLines(versionsInput.get().getAsFile().toPath());
+        ResourceInformation output = new ResourceInformation(hash, platforms, versions);
 
-        platforms.put("hash", EncodingGroovyMethods.encodeHex(hash.digest()).toString());
-        platforms.put("versions", versions);
         GsonBuilder builder = new GsonBuilder();
         builder.setPrettyPrinting();
-        var json = builder.create().toJson(platforms);
+        var json = builder.create().toJson(output);
         Files.writeString(hashFile.get().getAsFile().toPath(), json, Charset.defaultCharset());
     }
 }