Web MIDI: move MIDI message validating logic into message_util.{cc|h}

media/midi/message_util_unittest.cc

Index: media/midi/message_util_unittest.cc
diff --git a/media/midi/message_util_unittest.cc b/media/midi/message_util_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..91450ff43afa405e1cecc1ec3b16103861406fd6
--- /dev/null
+++ b/media/midi/message_util_unittest.cc
@@ -0,0 +1,108 @@
+// Copyright 2013 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/midi/message_util.h"
+
+#include <stdint.h>
+
+#include "base/macros.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace midi {
+namespace {
+
+const uint8_t kGMOn[] = {0xf0, 0x7e, 0x7f, 0x09, 0x01, 0xf7};
+const uint8_t kGSOn[] = {
+    0xf0, 0x41, 0x10, 0x42, 0x12, 0x40, 0x00, 0x7f, 0x00, 0x41, 0xf7,
+};
+const uint8_t kNoteOn[] = {0x90, 0x3c, 0x7f};
+const uint8_t kNoteOnWithRunningStatus[] = {
+    0x90, 0x3c, 0x7f, 0x3c, 0x7f, 0x3c, 0x7f,
+};
+const uint8_t kNoteOnWithRealTimeClock[] = {
+    0x90, 0xf8, 0x3c, 0x7f, 0x90, 0xf8, 0x3c, 0xf8, 0x7f, 0xf8,
+};
+const uint8_t kGMOnWithRealTimeClock[] = {
+    0xf0, 0xf8, 0x7e, 0x7f, 0x09, 0x01, 0xf8, 0xf7,
+};
+const uint8_t kSystemCommonMessageReserved1[] = {0xf4};
+const uint8_t kSystemCommonMessageReserved2[] = {0xf5};
+const uint8_t kSystemCommonMessageTuneRequest[] = {0xf6};
+const uint8_t kChannelPressure[] = {0xd0, 0x01};
+const uint8_t kChannelPressureWithRunningStatus[] = {0xd0, 0x01, 0x01, 0x01};
+const uint8_t kTimingClock[] = {0xf8};
+const uint8_t kBrokenData1[] = {0x90};
+const uint8_t kBrokenData2[] = {0xf7};
+const uint8_t kBrokenData3[] = {0xf2, 0x00};
+const uint8_t kDataByte0[] = {0x00};
+
+template <typename T, size_t N>
+const std::vector<T> AsVector(const T (&data)[N]) {
+  std::vector<T> buffer;
+  buffer.insert(buffer.end(), data, data + N);
+  return buffer;
+}
+
+template <typename T, size_t N>
+void PushToVector(const T (&data)[N], std::vector<T>* buffer) {
+  buffer->insert(buffer->end(), data, data + N);
+}
+
+TEST(MidiMessageUtilTest, GetMessageLength) {
+  // Check basic functionarity
+  EXPECT_EQ(arraysize(kNoteOn), GetMessageLength(kNoteOn[0]));
+  EXPECT_EQ(arraysize(kChannelPressure), GetMessageLength(kChannelPressure[0]));
+  EXPECT_EQ(arraysize(kTimingClock), GetMessageLength(kTimingClock[0]));
+  EXPECT_EQ(arraysize(kSystemCommonMessageTuneRequest),
+            GetMessageLength(kSystemCommonMessageTuneRequest[0]));
+
+  // SysEx message should be mapped to 0-length
+  EXPECT_EQ(0u, GetMessageLength(kGMOn[0]));
+
+  // Any reserved message should be mapped to 0-length
+  EXPECT_EQ(0u, GetMessageLength(kSystemCommonMessageReserved1[0]));
+  EXPECT_EQ(0u, GetMessageLength(kSystemCommonMessageReserved2[0]));
+
+  // Any data byte should be mapped to 0-length
+  EXPECT_EQ(0u, GetMessageLength(kGMOn[1]));
+  EXPECT_EQ(0u, GetMessageLength(kNoteOn[1]));
+  EXPECT_EQ(0u, GetMessageLength(kChannelPressure[1]));
+}
+
+TEST(MidiMessageUtilTest, IsValidWebMIDIData) {
+  // Test single event scenario
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kGMOn)));
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kGSOn)));
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kNoteOn)));
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kChannelPressure)));
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kTimingClock)));
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kBrokenData1)));
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kBrokenData2)));
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kBrokenData3)));
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kDataByte0)));
+
+  // MIDI running status should be disallowed
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kNoteOnWithRunningStatus)));
+  EXPECT_FALSE(IsValidWebMIDIData(AsVector(kChannelPressureWithRunningStatus)));
+
+  // Multiple messages are allowed as long as each of them is complete.
+  {
+    std::vector<uint8_t> buffer;
+    PushToVector(kGMOn, &buffer);
+    PushToVector(kNoteOn, &buffer);
+    PushToVector(kGSOn, &buffer);
+    PushToVector(kTimingClock, &buffer);
+    PushToVector(kNoteOn, &buffer);
+    EXPECT_TRUE(IsValidWebMIDIData(buffer));
+    PushToVector(kBrokenData1, &buffer);
+    EXPECT_FALSE(IsValidWebMIDIData(buffer));
+  }
+
+  // MIDI realtime message can be placed at any position.
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kNoteOnWithRealTimeClock)));
+  EXPECT_TRUE(IsValidWebMIDIData(AsVector(kGMOnWithRealTimeClock)));
+}
+
+}  // namespace
+}  // namespace midi