| /* |
| * Copyright (C) 2009 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. |
| */ |
| |
| #ifndef DATA_SOURCE_H_ |
| |
| #define DATA_SOURCE_H_ |
| |
| #include <sys/types.h> |
| #include <media/stagefright/foundation/ADebug.h> |
| #include <media/stagefright/MediaErrors.h> |
| #include <utils/Errors.h> |
| #include <utils/KeyedVector.h> |
| #include <utils/List.h> |
| #include <utils/RefBase.h> |
| #include <utils/threads.h> |
| #include <drm/DrmManagerClient.h> |
| |
| namespace android { |
| |
| struct AMessage; |
| struct AString; |
| class IDataSource; |
| struct IMediaHTTPService; |
| class String8; |
| struct HTTPBase; |
| |
| class DataSource : public RefBase { |
| public: |
| enum Flags { |
| kWantsPrefetching = 1, |
| kStreamedFromLocalHost = 2, |
| kIsCachingDataSource = 4, |
| kIsHTTPBasedSource = 8, |
| }; |
| |
| static sp<DataSource> CreateFromURI( |
| const sp<IMediaHTTPService> &httpService, |
| const char *uri, |
| const KeyedVector<String8, String8> *headers = NULL, |
| String8 *contentType = NULL, |
| HTTPBase *httpSource = NULL); |
| |
| static sp<DataSource> CreateMediaHTTP(const sp<IMediaHTTPService> &httpService); |
| static sp<DataSource> CreateFromIDataSource(const sp<IDataSource> &source); |
| |
| DataSource() {} |
| |
| virtual status_t initCheck() const = 0; |
| |
| // Returns the number of bytes read, or -1 on failure. It's not an error if |
| // this returns zero; it just means the given offset is equal to, or |
| // beyond, the end of the source. |
| virtual ssize_t readAt(off64_t offset, void *data, size_t size) = 0; |
| |
| // Convenience methods: |
| bool getUInt16(off64_t offset, uint16_t *x); |
| bool getUInt24(off64_t offset, uint32_t *x); // 3 byte int, returned as a 32-bit int |
| bool getUInt32(off64_t offset, uint32_t *x); |
| bool getUInt64(off64_t offset, uint64_t *x); |
| |
| // Reads in "count" entries of type T into vector *x. |
| // Returns true if "count" entries can be read. |
| // If fewer than "count" entries can be read, return false. In this case, |
| // the output vector *x will still have those entries that were read. Call |
| // x->size() to obtain the number of entries read. |
| // The optional parameter chunkSize specifies how many entries should be |
| // read from the data source at one time into a temporary buffer. Increasing |
| // chunkSize can improve the performance at the cost of extra memory usage. |
| // The default value for chunkSize is set to read at least 4k bytes at a |
| // time, depending on sizeof(T). |
| template <typename T> |
| bool getVector(off64_t offset, Vector<T>* x, size_t count, |
| size_t chunkSize = (4095 / sizeof(T)) + 1); |
| |
| // May return ERROR_UNSUPPORTED. |
| virtual status_t getSize(off64_t *size); |
| |
| virtual uint32_t flags() { |
| return 0; |
| } |
| |
| virtual String8 toString() { |
| return String8("<unspecified>"); |
| } |
| |
| virtual status_t reconnectAtOffset(off64_t offset) { |
| return ERROR_UNSUPPORTED; |
| } |
| |
| //////////////////////////////////////////////////////////////////////////// |
| |
| bool sniff(String8 *mimeType, float *confidence, sp<AMessage> *meta); |
| |
| // The sniffer can optionally fill in "meta" with an AMessage containing |
| // a dictionary of values that helps the corresponding extractor initialize |
| // its state without duplicating effort already exerted by the sniffer. |
| typedef bool (*SnifferFunc)( |
| const sp<DataSource> &source, String8 *mimeType, |
| float *confidence, sp<AMessage> *meta); |
| |
| static void RegisterDefaultSniffers(); |
| |
| // for DRM |
| virtual sp<DecryptHandle> DrmInitialization(const char *mime = NULL) { |
| return NULL; |
| } |
| virtual void getDrmInfo(sp<DecryptHandle> &handle, DrmManagerClient **client) {}; |
| |
| virtual String8 getUri() { |
| return String8(); |
| } |
| |
| virtual String8 getMIMEType() const; |
| |
| virtual void close() {}; |
| |
| protected: |
| virtual ~DataSource() {} |
| |
| private: |
| static Mutex gSnifferMutex; |
| static List<SnifferFunc> gSniffers; |
| static bool gSniffersRegistered; |
| |
| static void RegisterSniffer_l(SnifferFunc func); |
| |
| DataSource(const DataSource &); |
| DataSource &operator=(const DataSource &); |
| }; |
| |
| template <typename T> |
| bool DataSource::getVector(off64_t offset, Vector<T>* x, size_t count, |
| size_t chunkSize) |
| { |
| x->clear(); |
| if (chunkSize == 0) { |
| return false; |
| } |
| if (count == 0) { |
| return true; |
| } |
| |
| T tmp[chunkSize]; |
| ssize_t numBytesRead; |
| size_t numBytesPerChunk = chunkSize * sizeof(T); |
| size_t i; |
| |
| for (i = 0; i + chunkSize < count; i += chunkSize) { |
| // This loops is executed when more than chunkSize records need to be |
| // read. |
| numBytesRead = this->readAt(offset, (void*)&tmp, numBytesPerChunk); |
| if (numBytesRead == -1) { // If readAt() returns -1, there is an error. |
| return false; |
| } |
| if (numBytesRead < numBytesPerChunk) { |
| // This case is triggered when the stream ends before the whole |
| // chunk is read. |
| x->appendArray(tmp, (size_t)numBytesRead / sizeof(T)); |
| return false; |
| } |
| x->appendArray(tmp, chunkSize); |
| offset += numBytesPerChunk; |
| } |
| |
| // There are (count - i) more records to read. |
| // Right now, (count - i) <= chunkSize. |
| // We do the same thing as above, but with chunkSize replaced by count - i. |
| numBytesRead = this->readAt(offset, (void*)&tmp, (count - i) * sizeof(T)); |
| if (numBytesRead == -1) { |
| return false; |
| } |
| x->appendArray(tmp, (size_t)numBytesRead / sizeof(T)); |
| return x->size() == count; |
| } |
| |
| } // namespace android |
| |
| #endif // DATA_SOURCE_H_ |