From 2141f1073ec158687f7ef5972f4c8595eb6d3bb4 Mon Sep 17 00:00:00 2001
From: Alan Evans <alan@signal.org>
Date: Sat, 24 Aug 2019 17:54:29 +0100
Subject: [PATCH] Ensure memory file descriptor is available.

---
 .../securesms/mms/MediaConstraints.java       |  4 ++--
 .../securesms/util/MemoryFileDescriptor.java  | 24 +++++++++++++++++++
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/src/org/thoughtcrime/securesms/mms/MediaConstraints.java b/src/org/thoughtcrime/securesms/mms/MediaConstraints.java
index dab8c05fa0..614ac7ba24 100644
--- a/src/org/thoughtcrime/securesms/mms/MediaConstraints.java
+++ b/src/org/thoughtcrime/securesms/mms/MediaConstraints.java
@@ -6,13 +6,13 @@ import android.os.Build;
 import android.util.Pair;
 
 import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
 
 import org.thoughtcrime.securesms.attachments.Attachment;
 import org.thoughtcrime.securesms.logging.Log;
 import org.thoughtcrime.securesms.util.BitmapDecodingException;
 import org.thoughtcrime.securesms.util.BitmapUtil;
 import org.thoughtcrime.securesms.util.MediaUtil;
+import org.thoughtcrime.securesms.util.MemoryFileDescriptor;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -76,6 +76,6 @@ public abstract class MediaConstraints {
   }
 
   public static boolean isVideoTranscodeAvailable() {
-    return Build.VERSION.SDK_INT >= 26;
+    return Build.VERSION.SDK_INT >= 26 && MemoryFileDescriptor.supported();
   }
 }
diff --git a/src/org/thoughtcrime/securesms/util/MemoryFileDescriptor.java b/src/org/thoughtcrime/securesms/util/MemoryFileDescriptor.java
index e8b7b724d9..c76775bf81 100644
--- a/src/org/thoughtcrime/securesms/util/MemoryFileDescriptor.java
+++ b/src/org/thoughtcrime/securesms/util/MemoryFileDescriptor.java
@@ -22,9 +22,33 @@ public final class MemoryFileDescriptor implements Closeable {
 
   private static final String TAG = Log.tag(MemoryFileDescriptor.class);
 
+  private static Boolean supported;
+
   private final ParcelFileDescriptor parcelFileDescriptor;
   private final AtomicLong           sizeEstimate;
 
+  /**
+   * Does this device support memory file descriptor.
+   */
+  public synchronized static boolean supported() {
+    if (supported == null) {
+      try {
+        int fileDescriptor = FileUtils.createMemoryFileDescriptor("CHECK");
+
+        if (fileDescriptor < 0) {
+          supported = false;
+          Log.w(TAG, "MemoryFileDescriptor is not available.");
+        } else {
+          supported = true;
+          ParcelFileDescriptor.adoptFd(fileDescriptor).close();
+        }
+      } catch (IOException e) {
+        Log.w(TAG, e);
+      }
+    }
+    return supported;
+  }
+
   /**
    * memfd files do not show on the available RAM, so we must track our allocations in addition.
    */