Fix InMemoryUrlProtocol available_bytes computation.

media/filters/in_memory_url_protocol_unittest.cc

Index: media/filters/in_memory_url_protocol_unittest.cc
diff --git a/media/filters/in_memory_url_protocol_unittest.cc b/media/filters/in_memory_url_protocol_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7b615cdd04184d4212dc18ecb703feb81c63cfcb
--- /dev/null
+++ b/media/filters/in_memory_url_protocol_unittest.cc
@@ -0,0 +1,51 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "media/ffmpeg/ffmpeg_common.h"
+#include "media/filters/in_memory_url_protocol.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace media {
+
+static const uint8 kData[] = { 0x01, 0x02, 0x03, 0x04 };
+
+TEST(InMemoryUrlProtocolTest, ReadFromLargeBuffer) {
+  InMemoryUrlProtocol protocol(kData, std::numeric_limits<int64>::max(), false);
+
+  uint8 out[sizeof(kData)];
+  EXPECT_EQ(4, protocol.Read(sizeof(out), out));
+  EXPECT_EQ(0, memcmp(out, kData, sizeof(out)));
+}
+
+TEST(InMemoryUrlProtocolTest, ReadWithNegativeSize) {
+  InMemoryUrlProtocol protocol(kData, sizeof(kData), false);
+
+  uint8 out[sizeof(kData)];
+  EXPECT_EQ(AVERROR(EIO), protocol.Read(-2, out));
+}
+
+TEST(InMemoryUrlProtocolTest, ReadWithZeroSize) {
+  InMemoryUrlProtocol protocol(kData, sizeof(kData), false);
+
+  uint8 out;
+  EXPECT_EQ(0, protocol.Read(0, &out));
+}
+
+TEST(InMemoryUrlProtocolTest, SetPosition) {
+  InMemoryUrlProtocol protocol(kData, sizeof(kData), false);
+
+  EXPECT_FALSE(protocol.SetPosition(-1));
+  EXPECT_FALSE(protocol.SetPosition(sizeof(kData) + 1));
+
+  uint8 out;
+  EXPECT_TRUE(protocol.SetPosition(sizeof(kData)));
+  EXPECT_EQ(0, protocol.Read(1, &out));
+
+  int i = sizeof(kData) / 2;
+  EXPECT_TRUE(protocol.SetPosition(i));
+  EXPECT_EQ(1, protocol.Read(1, &out));
+  EXPECT_EQ(kData[i], out);
+}
+
+}  // namespace media