Revert "Revert "Initial implementation of USB Audio output.""

This reverts commit f2f80c09b668176b3b1e619457ae628432636507.

3 files changed, 413 insertions, 0 deletions

diff --git a/core/java/android/alsa/AlsaCardsParser.java b/core/java/android/alsa/AlsaCardsParser.java
new file mode 100644
index 0000000..f9af979
--- /dev/null
+++ b/core/java/android/alsa/AlsaCardsParser.java
@@ -0,0 +1,116 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.alsascan;
+
+import android.util.Slog;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Vector;
+
+/**
+ * @hide Retrieves information from an ALSA "cards" file.
+ */
+public class AlsaCardsParser {
+    private static final String TAG = "AlsaCardsParser";
+
+    private static LineTokenizer tokenizer_ = new LineTokenizer(" :[]");
+
+    public class AlsaCardRecord {
+        public int mCardNum = -1;
+        public String mField1 = "";
+        public String mCardName = "";
+        public String mCardDescription = "";
+
+        public AlsaCardRecord() {}
+
+        public boolean parse(String line, int lineIndex) {
+            int tokenIndex = 0;
+            int delimIndex = 0;
+            if (lineIndex == 0) {
+                // line # (skip)
+                tokenIndex = tokenizer_.nextToken(line, tokenIndex);
+                delimIndex = tokenizer_.nextDelimiter(line, tokenIndex);
+
+                // mField1
+                tokenIndex = tokenizer_.nextToken(line, delimIndex);
+                delimIndex = tokenizer_.nextDelimiter(line, tokenIndex);
+                mField1 = line.substring(tokenIndex, delimIndex);
+
+                // mCardName
+                tokenIndex = tokenizer_.nextToken(line, delimIndex);
+                // delimIndex = tokenizer_.nextDelimiter(line, tokenIndex);
+                mCardName = line.substring(tokenIndex);
+                // done
+              } else if (lineIndex == 1) {
+                  tokenIndex = tokenizer_.nextToken(line, 0);
+                  if (tokenIndex != -1) {
+                      mCardDescription = line.substring(tokenIndex);
+                  }
+            }
+
+            return true;
+        }
+
+        public String textFormat() {
+          return mCardName + " : " + mCardDescription;
+        }
+    }
+
+    private Vector<AlsaCardRecord> cardRecords_ = new Vector<AlsaCardRecord>();
+
+    public void scan() {
+          cardRecords_.clear();
+          final String cardsFilePath = "/proc/asound/cards";
+          File cardsFile = new File(cardsFilePath);
+          try {
+              FileReader reader = new FileReader(cardsFile);
+              BufferedReader bufferedReader = new BufferedReader(reader);
+              String line = "";
+              while ((line = bufferedReader.readLine()) != null) {
+                  AlsaCardRecord cardRecord = new AlsaCardRecord();
+                  cardRecord.parse(line, 0);
+                  cardRecord.parse(line = bufferedReader.readLine(), 1);
+                  cardRecords_.add(cardRecord);
+              }
+              reader.close();
+          } catch (FileNotFoundException e) {
+              e.printStackTrace();
+          } catch (IOException e) {
+              e.printStackTrace();
+          }
+      }
+
+      public AlsaCardRecord getCardRecordAt(int index) {
+          return cardRecords_.get(index);
+      }
+
+      public int getNumCardRecords() {
+          return cardRecords_.size();
+      }
+
+    public void Log() {
+      int numCardRecs = getNumCardRecords();
+      for (int index = 0; index < numCardRecs; ++index) {
+          Slog.w(TAG, "usb:" + getCardRecordAt(index).textFormat());
+      }
+    }
+
+    public AlsaCardsParser() {}
+}
diff --git a/core/java/android/alsa/AlsaDevicesParser.java b/core/java/android/alsa/AlsaDevicesParser.java
new file mode 100644
index 0000000..3835942
--- /dev/null
+++ b/core/java/android/alsa/AlsaDevicesParser.java
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.alsascan;
+
+import android.util.Slog;
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.Vector;
+
+/**
+ * @hide
+ * Retrieves information from an ALSA "devices" file.
+ */
+public class AlsaDevicesParser {
+    private static final String TAG = "AlsaDevicesParser";
+
+    private static final int kIndex_CardDeviceField = 5;
+    private static final int kStartIndex_CardNum = 6;
+    private static final int kEndIndex_CardNum = 8; // one past
+    private static final int kStartIndex_DeviceNum = 9;
+    private static final int kEndIndex_DeviceNum = 11; // one past
+    private static final int kStartIndex_Type = 14;
+
+    private static LineTokenizer mTokenizer = new LineTokenizer(" :[]-");
+
+    private boolean mHasCaptureDevices = false;
+    private boolean mHasPlaybackDevices = false;
+    private boolean mHasMIDIDevices = false;
+
+    public class AlsaDeviceRecord {
+        public static final int kDeviceType_Unknown = -1;
+        public static final int kDeviceType_Audio = 0;
+        public static final int kDeviceType_Control = 1;
+        public static final int kDeviceType_MIDI = 2;
+
+        public static final int kDeviceDir_Unknown = -1;
+        public static final int kDeviceDir_Capture = 0;
+        public static final int kDeviceDir_Playback = 1;
+
+        int mCardNum = -1;
+        int mDeviceNum = -1;
+        int mDeviceType = kDeviceType_Unknown;
+        int mDeviceDir = kDeviceDir_Unknown;
+
+        public AlsaDeviceRecord() {
+        }
+
+        public boolean parse(String line) {
+            // "0123456789012345678901234567890"
+            // "  2: [ 0-31]: digital audio playback"
+            // "  3: [ 0-30]: digital audio capture"
+            // " 35: [ 1]   : control"
+            // " 36: [ 2- 0]: raw midi"
+
+            final int kToken_LineNum = 0;
+            final int kToken_CardNum = 1;
+            final int kToken_DeviceNum = 2;
+            final int kToken_Type0 = 3; // "digital", "control", "raw"
+            final int kToken_Type1 = 4; // "audio", "midi"
+            final int kToken_Type2 = 5; // "capture", "playback"
+
+            int tokenOffset = 0;
+            int delimOffset = 0;
+            int tokenIndex = kToken_LineNum;
+            while (true) {
+                tokenOffset = mTokenizer.nextToken(line, delimOffset);
+                if (tokenOffset == LineTokenizer.kTokenNotFound) {
+                    break; // bail
+                }
+                delimOffset = mTokenizer.nextDelimiter(line, tokenOffset);
+                if (delimOffset == LineTokenizer.kTokenNotFound) {
+                    delimOffset = line.length();
+                }
+                String token = line.substring(tokenOffset, delimOffset);
+
+                switch (tokenIndex) {
+                case kToken_LineNum:
+                    // ignore
+                    break;
+
+                case kToken_CardNum:
+                    mCardNum = Integer.parseInt(token);
+                    if (line.charAt(delimOffset) != '-') {
+                        tokenIndex++; // no device # in the token stream
+                    }
+                    break;
+
+                case kToken_DeviceNum:
+                    mDeviceNum = Integer.parseInt(token);
+                    break;
+
+                case kToken_Type0:
+                    if (token.equals("digital")) {
+                        // NOP
+                    } else if (token.equals("control")) {
+                        mDeviceType = kDeviceType_Control;
+                    } else if (token.equals("raw")) {
+                        // NOP
+                    }
+                    break;
+
+                case kToken_Type1:
+                    if (token.equals("audio")) {
+                        mDeviceType = kDeviceType_Audio;
+                    } else if (token.equals("midi")) {
+                        mDeviceType = kDeviceType_MIDI;
+                        mHasMIDIDevices = true;
+                    }
+                    break;
+
+                case kToken_Type2:
+                    if (token.equals("capture")) {
+                        mDeviceDir = kDeviceDir_Capture;
+                        mHasCaptureDevices = true;
+                    } else if (token.equals("playback")) {
+                        mDeviceDir = kDeviceDir_Playback;
+                        mHasPlaybackDevices = true;
+                    }
+                    break;
+                } // switch (tokenIndex)
+
+                tokenIndex++;
+            } // while (true)
+
+            return true;
+        } // parse()
+
+        public String textFormat() {
+            StringBuilder sb = new StringBuilder();
+            sb.append("[" + mCardNum + ":" + mDeviceNum + "]");
+
+            switch (mDeviceType) {
+            case kDeviceType_Unknown:
+                sb.append(" N/A");
+                break;
+            case kDeviceType_Audio:
+                sb.append(" Audio");
+                break;
+            case kDeviceType_Control:
+                sb.append(" Control");
+                break;
+            case kDeviceType_MIDI:
+                sb.append(" MIDI");
+                break;
+            }
+
+            switch (mDeviceDir) {
+            case kDeviceDir_Unknown:
+                sb.append(" N/A");
+                break;
+            case kDeviceDir_Capture:
+                sb.append(" Capture");
+                break;
+            case kDeviceDir_Playback:
+                sb.append(" Playback");
+                break;
+            }
+
+            return sb.toString();
+        }
+    }
+
+    private Vector<AlsaDeviceRecord>
+            deviceRecords_ = new Vector<AlsaDeviceRecord>();
+
+    private boolean isLineDeviceRecord(String line) {
+        return line.charAt(kIndex_CardDeviceField) == '[';
+    }
+
+    public AlsaDevicesParser() {
+    }
+
+    public int getNumDeviceRecords() {
+        return deviceRecords_.size();
+    }
+
+    public AlsaDeviceRecord getDeviceRecordAt(int index) {
+        return deviceRecords_.get(index);
+    }
+
+    public void Log() {
+        int numDevRecs = getNumDeviceRecords();
+        for (int index = 0; index < numDevRecs; ++index) {
+            Slog.w(TAG, "usb:" + getDeviceRecordAt(index).textFormat());
+        }
+    }
+
+    public boolean hasPlaybackDevices() {
+        return mHasPlaybackDevices;
+    }
+
+    public boolean hasCaptureDevices() {
+        return mHasCaptureDevices;
+    }
+
+    public boolean hasMIDIDevices() {
+        return mHasMIDIDevices;
+    }
+
+    public void scan() {
+        deviceRecords_.clear();
+
+        final String devicesFilePath = "/proc/asound/devices";
+        File devicesFile = new File(devicesFilePath);
+        try {
+            FileReader reader = new FileReader(devicesFile);
+            BufferedReader bufferedReader = new BufferedReader(reader);
+            String line = "";
+            while ((line = bufferedReader.readLine()) != null) {
+                if (isLineDeviceRecord(line)) {
+                    AlsaDeviceRecord deviceRecord = new AlsaDeviceRecord();
+                    deviceRecord.parse(line);
+                    deviceRecords_.add(deviceRecord);
+                }
+            }
+            reader.close();
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+} // class AlsaDevicesParser
+
diff --git a/core/java/android/alsa/LineTokenizer.java b/core/java/android/alsa/LineTokenizer.java
new file mode 100644
index 0000000..c138fc5
--- /dev/null
+++ b/core/java/android/alsa/LineTokenizer.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.android.alsascan;
+
+/**
+ * @hide
+ * Breaks lines in an ALSA "cards" or "devices" file into tokens.
+ * TODO(pmclean) Look into replacing this with String.split().
+ */
+public class LineTokenizer {
+    public static final int kTokenNotFound = -1;
+
+    private String mDelimiters = "";
+
+    public LineTokenizer(String delimiters) {
+        mDelimiters = delimiters;
+    }
+
+    int nextToken(String line, int startIndex) {
+        int len = line.length();
+        int offset = startIndex;
+        for (; offset < len; offset++) {
+            if (mDelimiters.indexOf(line.charAt(offset)) == -1) {
+                // past a delimiter
+                break;
+            }
+      }
+
+      return offset < len ? offset : kTokenNotFound;
+    }
+
+    int nextDelimiter(String line, int startIndex) {
+        int len = line.length();
+        int offset = startIndex;
+        for (; offset < len; offset++) {
+            if (mDelimiters.indexOf(line.charAt(offset)) != -1) {
+                // past a delimiter
+                break;
+            }
+        }
+
+      return offset < len ? offset : kTokenNotFound;
+    }
+}