1 /*
2  * Copyright (C) 2008-2011 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ANDROID_AUDIOPARAMETER_H_
18 #define ANDROID_AUDIOPARAMETER_H_
19 
20 #include <utils/Errors.h>
21 #include <utils/KeyedVector.h>
22 #include <utils/String8.h>
23 
24 namespace android {
25 
26 class AudioParameter {
27 
28 public:
AudioParameter()29     AudioParameter() {}
30     AudioParameter(const String8& keyValuePairs);
31     virtual ~AudioParameter();
32 
33     // reserved parameter keys for changing standard parameters with setParameters() function.
34     // Using these keys is mandatory for AudioFlinger to properly monitor audio output/input
35     // configuration changes and act accordingly.
36     //  keyRouting: to change audio routing, value is an int in audio_devices_t
37     //  keySamplingRate: to change sampling rate routing, value is an int
38     //  keyFormat: to change audio format, value is an int in audio_format_t
39     //  keyChannels: to change audio channel configuration, value is an int in audio_channels_t
40     //  keyFrameCount: to change audio output frame count, value is an int
41     //  keyInputSource: to change audio input source, value is an int in audio_source_t
42     //     (defined in media/mediarecorder.h)
43     //  keyScreenState: either "on" or "off"
44     static const char * const keyRouting;
45     static const char * const keySamplingRate;
46     static const char * const keyFormat;
47     static const char * const keyChannels;
48     static const char * const keyFrameCount;
49     static const char * const keyInputSource;
50     static const char * const keyScreenState;
51 
52     String8 toString();
53 
54     status_t add(const String8& key, const String8& value);
55     status_t addInt(const String8& key, const int value);
56     status_t addFloat(const String8& key, const float value);
57 
58     status_t remove(const String8& key);
59 
60     status_t get(const String8& key, String8& value);
61     status_t getInt(const String8& key, int& value);
62     status_t getFloat(const String8& key, float& value);
63     status_t getAt(size_t index, String8& key, String8& value);
64 
size()65     size_t size() { return mParameters.size(); }
66 
67 private:
68     String8 mKeyValuePairs;
69     KeyedVector <String8, String8> mParameters;
70 };
71 
72 };  // namespace android
73 
74 #endif  /*ANDROID_AUDIOPARAMETER_H_*/
75