Merge "GZIPInputStream: Fix handling of header CRCs."

2 files changed, 19 insertions, 3 deletions

diff --git a/luni/src/main/java/java/util/zip/GZIPInputStream.java b/luni/src/main/java/java/util/zip/GZIPInputStream.java
index 1bfc496..afbbafe 100644
--- a/luni/src/main/java/java/util/zip/GZIPInputStream.java
+++ b/luni/src/main/java/java/util/zip/GZIPInputStream.java
@@ -243,7 +243,7 @@ public class GZIPInputStream extends InflaterInputStream {
         }
         if (hcrc) {
             Streams.readFully(in, header, 0, 2);
-            short crc16 = Memory.peekShort(scratch, 0, ByteOrder.LITTLE_ENDIAN);
+            short crc16 = Memory.peekShort(header, 0, ByteOrder.LITTLE_ENDIAN);
             if ((short) crc.getValue() != crc16) {
                 throw new IOException("CRC mismatch");
             }
diff --git a/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java b/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
index 494520a..153f324 100644
--- a/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
+++ b/luni/src/test/java/libcore/java/util/zip/GZIPInputStreamTest.java
@@ -35,14 +35,30 @@ import libcore.io.Streams;
 public final class GZIPInputStreamTest extends TestCase {
 
     private static final byte[] HELLO_WORLD_GZIPPED = new byte[] {
-        31, -117, 8, 0, 0, 0, 0, 0, 0, 0, -13, 72, -51, -55, -55, 87, 8, -49,
-        47, -54, 73, 1, 0, 86, -79, 23, 74, 11, 0, 0, 0
+        31, -117, 8, 0, 0, 0, 0, 0, 0, 0,  // 10 byte header
+        -13, 72, -51, -55, -55, 87, 8, -49, 47, -54, 73, 1, 0, 86, -79, 23, 74, 11, 0, 0, 0  // data
+    };
+
+    /**
+     * This is the same as the above, except that the 4th header byte is 2 (FHCRC flag)
+     * and the 2 bytes after the header make up the CRC.
+     *
+     * Constructed manually because none of the commonly used tools appear to emit header CRCs.
+     */
+    private static final byte[] HELLO_WORLD_GZIPPED_WITH_HEADER_CRC = new byte[] {
+        31, -117, 8, 2, 0, 0, 0, 0, 0, 0,  // 10 byte header
+        29, 38, // 2 byte CRC.
+        -13, 72, -51, -55, -55, 87, 8, -49, 47, -54, 73, 1, 0, 86, -79, 23, 74, 11, 0, 0, 0  // data
     };
 
     public void testShortMessage() throws IOException {
         assertEquals("Hello World", new String(gunzip(HELLO_WORLD_GZIPPED), "UTF-8"));
     }
 
+    public void testShortMessageWithCrc() throws IOException {
+        assertEquals("Hello World", new String(gunzip(HELLO_WORLD_GZIPPED_WITH_HEADER_CRC), "UTF-8"));
+    }
+
     public void testLongMessage() throws IOException {
         byte[] data = new byte[1024 * 1024];
         new Random().nextBytes(data);