1 files changed, 163 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewInputStream.java b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewInputStream.java
new file mode 100644
index 0000000000..97b14f628d
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/geckoview/GeckoViewInputStream.java
@@ -0,0 +1,163 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.geckoview;
+
+import android.util.Log;
+import androidx.annotation.AnyThread;
+import androidx.annotation.NonNull;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.channels.Channels;
+import java.nio.channels.ReadableByteChannel;
+import org.mozilla.gecko.annotation.WrapForJNI;
+
+/** This class provides a Gecko nsIInputStream wrapper for a Java {@link InputStream}. */
+@WrapForJNI
+@AnyThread
+/* package */ class GeckoViewInputStream {
+  private static final String LOGTAG = "GeckoViewInputStream";
+  private static final int BUFFER_SIZE = 4096;
+
+  protected final ByteBuffer mBuffer = ByteBuffer.allocateDirect(BUFFER_SIZE);
+  private ReadableByteChannel mChannel;
+  private InputStream mIs = null;
+  private boolean mMustGetData = true;
+  private int mPos = 0;
+  private int mSize;
+
+  /**
+   * Set an input stream.
+   *
+   * @param is the {@link InputStream} to set.
+   */
+  protected void setInputStream(final @NonNull InputStream is) {
+    mIs = is;
+    mChannel = Channels.newChannel(is);
+  }
+
+  /**
+   * Check if there is a stream.
+   *
+   * @return true if there is no stream.
+   */
+  public boolean isClosed() {
+    return mIs == null;
+  }
+
+  /**
+   * Called by native code to get the number of available bytes in the underlying stream.
+   *
+   * @return the number of available bytes.
+   */
+  public int available() {
+    if (mIs == null || mSize == -1) {
+      return 0;
+    }
+    try {
+      return Math.max(mIs.available(), mMustGetData ? 0 : mSize - mPos);
+    } catch (final IOException e) {
+      Log.e(LOGTAG, "Cannot get the number of available bytes", e);
+      return 0;
+    }
+  }
+
+  /** Close the underlying stream. */
+  public void close() {
+    if (mIs == null) {
+      return;
+    }
+    try {
+      mChannel.close();
+    } catch (final IOException e) {
+      Log.e(LOGTAG, "Cannot close the channel", e);
+    } finally {
+      mChannel = null;
+    }
+
+    try {
+      mIs.close();
+    } catch (final IOException e) {
+      Log.e(LOGTAG, "Cannot close the stream", e);
+    } finally {
+      mIs = null;
+    }
+  }
+
+  /**
+   * Called by native code to notify that the data have been consumed.
+   *
+   * @param length the number of consumed bytes.
+   * @return the position in the buffer.
+   */
+  public long consumedData(final int length) {
+    mPos += length;
+    if (mPos >= mSize) {
+      mPos = 0;
+      mMustGetData = true;
+    }
+    return mPos;
+  }
+
+  /**
+   * Check that the underlying stream starts with one of the given headers.
+   *
+   * @param headers the headers to check.
+   * @return true if one of the headers is found.
+   */
+  protected boolean checkHeaders(final @NonNull byte[][] headers) throws IOException {
+    read(0);
+    for (final byte[] header : headers) {
+      final int headerLength = header.length;
+      if (mSize < headerLength) {
+        continue;
+      }
+      int i = 0;
+      for (; i < headerLength; i++) {
+        if (mBuffer.get(i) != header[i]) {
+          break;
+        }
+      }
+      if (i == headerLength) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  /**
+   * Called by native code to read some bytes in the underlying stream.
+   *
+   * @param aCount the number of bytes to read.
+   * @return the number of read bytes, -1 in case of EOF.
+   * @throws IOException if an error occurs.
+   */
+  @WrapForJNI(exceptionMode = "nsresult")
+  public int read(final long aCount) throws IOException {
+    if (mIs == null) {
+      Log.e(LOGTAG, "The stream is closed.");
+      throw new IllegalStateException("Stream is closed");
+    }
+
+    if (!mMustGetData) {
+      return (int) Math.min((long) (mSize - mPos), aCount);
+    }
+
+    mMustGetData = false;
+    mBuffer.clear();
+
+    try {
+      mSize = mChannel.read(mBuffer);
+    } catch (final IOException e) {
+      Log.e(LOGTAG, "Cannot read some bytes", e);
+      throw e;
+    }
+    if (mSize == -1) {
+      return -1;
+    }
+
+    return (int) Math.min((long) mSize, aCount);
+  }
+}