fix write operation

glusterfs-java-filesystem/src/main/java/com/peircean/glusterfs/GlusterFileChannel.java

@@ -166,7 +166,7 @@ long readHelper(ByteBuffer[] byteBuffers, int offset, int length) throws IOExcep
     public int write(ByteBuffer byteBuffer) throws IOException {
         guardClosed();
         byte[] buf = byteBuffer.array();
-        int written = GLFS.glfs_write(fileptr, buf, buf.length, 0);
+        int written = GLFS.glfs_write(fileptr, buf, byteBuffer.limit(), 0);
         if (written < 0) {
             throw new IOException(UtilJNI.strerror());
         }
@@ -189,17 +189,16 @@ public long write(ByteBuffer[] byteBuffers, int offset, int length) throws IOExc
         }
 
         long totalWritten = 0L;
-
         for (int i = offset; i < length + offset; i++) {
             int remaining = byteBuffers[i].remaining();
             while (remaining > 0) {
                 byte[] bytes = byteBuffers[i].array();
-                int written = GLFS.glfs_write(fileptr, bytes, remaining, 0);
+                int written = GLFS.glfs_write(fileptr, bytes, remaining, byteBuffers[i].position());
                 if (written < 0) {
                     throw new IOException();
                 }
                 position += written;
-                byteBuffers[i].position(written);
+                byteBuffers[i].position(byteBuffers[i].position() + written);
                 totalWritten += written;
                 remaining = byteBuffers[i].remaining();
             }

glusterfs-java-filesystem/src/test/java/com/peircean/glusterfs/GlusterFileChannelTest.java

@@ -568,6 +568,7 @@ public void testWrite1Arg() throws IOException {
         when(GLFS.glfs_write(fileptr, bytes, bufferLength, 0)).thenReturn(bufferLength);
 
         doReturn(bytes).when(mockBuffer).array();
+        doReturn(bufferLength).when(mockBuffer).limit();
         doReturn(null).when(mockBuffer).position(bufferLength);
 
         int written = channel.write(mockBuffer);