Recover DSO not found error for BackupSoSource

Summary:
This stack aims to recover the work from an old diff D50323349.

As a first step, we only recover DSO error for BackupSoSource and we only reunpack reunpack if the missing library can be found inside the APK.

Reviewed By: adicatana

Differential Revision: D55876275

fbshipit-source-id: dee52793805f4886dccd060734d995be88ee023d

java/com/facebook/soloader/BackupSoSource.java

@@ -103,7 +103,28 @@ public void prepare(int flags) throws IOException {
     mInitialized = true;
   }
 
+  public boolean peekAndPrepareSoSource(String soName, int prepareFlags) throws IOException {
+    boolean found = false;
+    try (Unpacker u = makeUnpacker()) {
+      Dso[] dsos = u.getDsos();
+      for (Dso dso : dsos) {
+        if (dso.name.equals(soName)) {
+          LogUtil.e(SoLoader.TAG, "Found " + soName + " in " + getName());
+          found = true;
+          break;
+        }
+      }
+    }
+    if (!found) {
+      return false;
+    }
+    LogUtil.e(SoLoader.TAG, "Preparing " + getName());
+    prepare(prepareFlags);
+    return true;
+  }
+
   protected class ApkUnpacker extends Unpacker {
+
     @Override
     public Dso[] getDsos() throws IOException {
       ArrayList<Dso> dsos = new ArrayList<>();

java/com/facebook/soloader/recovery/ReunpackBackupSoSources.java

@@ -22,6 +22,7 @@
 import com.facebook.soloader.SoLoaderDSONotFoundError;
 import com.facebook.soloader.SoLoaderULError;
 import com.facebook.soloader.SoSource;
+import java.io.IOException;
 
 /**
  * RecoveryStrategy that detects cases when SoLoader failed to load a corrupted library, case in
@@ -38,26 +39,50 @@ public boolean recover(UnsatisfiedLinkError error, SoSource[] soSources) {
       // Only recover from SoLoaderULE errors
       return false;
     }
+    SoLoaderULError err = (SoLoaderULError) error;
+    String soName = err.getSoName();
+    String message = err.getMessage();
 
-    if (error instanceof SoLoaderDSONotFoundError) {
-      // Do not attempt to recover if DSO is not found
+    if (soName == null) {
+      LogUtil.e(SoLoader.TAG, "No so name provided in ULE, cannot recover");
       return false;
     }
 
-    SoLoaderULError err = (SoLoaderULError) error;
-    String message = err.getMessage();
-    if (message == null || (!message.contains("/app/") && !message.contains("/mnt/"))) {
-      // Do not attempt to recovery if the DSO wasn't in the data/app directory
+    if (err instanceof SoLoaderDSONotFoundError) {
+      // Recover if DSO is not found
+      logRecovery(err, soName);
+
+      return recoverDSONotFoundError(soSources, soName, 0);
+    } else if (message == null || (!message.contains("/app/") && !message.contains("/mnt/"))) {
+      // Don't recover if the DSO wasn't in the data/app directory
+
       return false;
+    } else {
+      logRecovery(err, soName);
+      return lazyPrepareBackupSoSource(soSources, soName);
     }
+  }
 
-    String soName = err.getSoName();
-    LogUtil.e(
-        SoLoader.TAG,
-        "Reunpacking BackupSoSources due to "
-            + error
-            + ((soName == null) ? "" : (", retrying for specific library " + soName)));
+  private boolean recoverDSONotFoundError(SoSource[] soSources, String soName, int prepareFlags) {
+    try {
+      for (SoSource soSource : soSources) {
+        if (!(soSource instanceof BackupSoSource)) {
+          continue;
+        }
+        BackupSoSource uss = (BackupSoSource) soSource;
 
+        if (uss.peekAndPrepareSoSource(soName, prepareFlags)) {
+          return true;
+        }
+      }
+      return false;
+    } catch (IOException ioException) {
+      LogUtil.e(SoLoader.TAG, "Failed to run recovery for backup so source due to: " + ioException);
+      return false;
+    }
+  }
+
+  private boolean lazyPrepareBackupSoSource(SoSource[] soSources, String soName) {
     for (SoSource soSource : soSources) {
       if (!(soSource instanceof BackupSoSource)) {
         // NonApk SoSources get reunpacked in ReunpackNonBackupSoSource recovery strategy
@@ -88,4 +113,13 @@ public boolean recover(UnsatisfiedLinkError error, SoSource[] soSources) {
 
     return false;
   }
+
+  private void logRecovery(Error error, String soName) {
+    LogUtil.e(
+        SoLoader.TAG,
+        "Reunpacking BackupSoSources due to "
+            + error
+            + ", retrying for specific library "
+            + soName);
+  }
 }