From 3c8fef2655e6a1375625e625339e29f8f7da967a Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Sun, 13 Oct 2019 11:05:03 +0200
Subject: [PATCH] SharedLibraryLoader: separate out extraction

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 .../android/util/SharedLibraryLoader.java     | 64 ++++++++++---------
 1 file changed, 35 insertions(+), 29 deletions(-)

diff --git a/app/src/main/java/com/wireguard/android/util/SharedLibraryLoader.java b/app/src/main/java/com/wireguard/android/util/SharedLibraryLoader.java
index 50026614..e3923d19 100644
--- a/app/src/main/java/com/wireguard/android/util/SharedLibraryLoader.java
+++ b/app/src/main/java/com/wireguard/android/util/SharedLibraryLoader.java
@@ -25,16 +25,7 @@ public final class SharedLibraryLoader {
     private SharedLibraryLoader() {
     }
 
-    public static void loadSharedLibrary(final Context context, final String libName) {
-        Throwable noAbiException;
-        try {
-            System.loadLibrary(libName);
-            return;
-        } catch (final UnsatisfiedLinkError e) {
-            Log.d(TAG, "Failed to load library normally, so attempting to extract from apk", e);
-            noAbiException = e;
-        }
-
+    public static boolean extractLibrary(final Context context, final String libName, final File destination) throws IOException {
         final Collection<String> apks = new HashSet<>();
         if (context.getApplicationInfo().sourceDir != null)
             apks.add(context.getApplicationInfo().sourceDir);
@@ -56,29 +47,44 @@ public final class SharedLibraryLoader {
                 final ZipEntry zipEntry = zipFile.getEntry(libZipPath);
                 if (zipEntry == null)
                     continue;
-                File f = null;
-                try {
-                    f = File.createTempFile("lib", ".so", context.getCacheDir());
-                    Log.d(TAG, "Extracting apk:/" + libZipPath + " to " + f.getAbsolutePath() + " and loading");
-                    try (final FileOutputStream out = new FileOutputStream(f);
-                         final InputStream in = zipFile.getInputStream(zipEntry)) {
-                        int len;
-                        while ((len = in.read(buffer)) != -1) {
-                            out.write(buffer, 0, len);
-                        }
+                Log.d(TAG, "Extracting apk:/" + libZipPath + " to " + destination.getAbsolutePath());
+                try (final FileOutputStream out = new FileOutputStream(destination);
+                     final InputStream in = zipFile.getInputStream(zipEntry)) {
+                    int len;
+                    while ((len = in.read(buffer)) != -1) {
+                        out.write(buffer, 0, len);
                     }
-                    System.load(f.getAbsolutePath());
-                    return;
-                } catch (final Exception e) {
-                    Log.d(TAG, "Failed to load library apk:/" + libZipPath, e);
-                    noAbiException = e;
-                } finally {
-                    if (f != null)
-                        // noinspection ResultOfMethodCallIgnored
-                        f.delete();
                 }
+                return true;
             }
         }
+        return false;
+    }
+
+    public static void loadSharedLibrary(final Context context, final String libName) {
+        Throwable noAbiException;
+        try {
+            System.loadLibrary(libName);
+            return;
+        } catch (final UnsatisfiedLinkError e) {
+            Log.d(TAG, "Failed to load library normally, so attempting to extract from apk", e);
+            noAbiException = e;
+        }
+        File f = null;
+        try {
+            f = File.createTempFile("lib", ".so", context.getCodeCacheDir());
+            if (extractLibrary(context, libName, f)) {
+                System.load(f.getAbsolutePath());
+                return;
+            }
+        } catch (final Exception e) {
+            Log.d(TAG, "Failed to load library apk:/" + libName, e);
+            noAbiException = e;
+        } finally {
+            if (f != null)
+                // noinspection ResultOfMethodCallIgnored
+                f.delete();
+        }
         if (noAbiException instanceof RuntimeException)
             throw (RuntimeException) noAbiException;
         throw new RuntimeException(noAbiException);