Home | History | Annotate | Download | only in stagefright 
      1 /*
      2  * Copyright (C) 2009 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 MEDIA_BUFFER_BASE_H_
     18 
     19 #define MEDIA_BUFFER_BASE_H_
     20 
     21 namespace android {
     22 
     23 class MediaBufferBase;
     24 class MetaDataBase;
     25 
     26 class MediaBufferObserver {
     27 public:
     28     MediaBufferObserver() {}
     29     virtual ~MediaBufferObserver() {}
     30 
     31     virtual void signalBufferReturned(MediaBufferBase *buffer) = 0;
     32 
     33 private:
     34     MediaBufferObserver(const MediaBufferObserver &);
     35     MediaBufferObserver &operator=(const MediaBufferObserver &);
     36 };
     37 
     38 class MediaBufferBase {
     39 public:
     40     static MediaBufferBase *Create(size_t size);
     41 
     42     // If MediaBufferGroup is set, decrement the local reference count;
     43     // if the local reference count drops to 0, return the buffer to the
     44     // associated MediaBufferGroup.
     45     //
     46     // If no MediaBufferGroup is set, the local reference count must be zero
     47     // when called, whereupon the MediaBuffer is deleted.
     48     virtual void release() = 0;
     49 
     50     // Increments the local reference count.
     51     // Use only when MediaBufferGroup is set.
     52     virtual void add_ref() = 0;
     53 
     54     virtual void *data() const = 0;
     55     virtual size_t size() const = 0;
     56 
     57     virtual size_t range_offset() const = 0;
     58     virtual size_t range_length() const = 0;
     59 
     60     virtual void set_range(size_t offset, size_t length) = 0;
     61 
     62     virtual MetaDataBase& meta_data() = 0;
     63 
     64     // Clears meta data and resets the range to the full extent.
     65     virtual void reset() = 0;
     66 
     67     virtual void setObserver(MediaBufferObserver *group) = 0;
     68 
     69     // Returns a clone of this MediaBufferBase increasing its reference
     70     // count. The clone references the same data but has its own range and
     71     // MetaData.
     72     virtual MediaBufferBase *clone() = 0;
     73 
     74     virtual int refcount() const = 0;
     75 
     76     virtual int localRefcount() const = 0;
     77     virtual int remoteRefcount() const = 0;
     78 
     79     virtual ~MediaBufferBase() {};
     80 };
     81 
     82 }  // namespace android
     83 
     84 #endif  // MEDIA_BUFFER_BASE_H_
     85