| /* |
| * 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_BASE_H_ |
| |
| #define DATA_SOURCE_BASE_H_ |
| |
| #include <sys/types.h> |
| #include <utils/Errors.h> |
| |
| namespace android { |
| |
| class String8; |
| |
| class DataSourceBase { |
| public: |
| enum Flags { |
| kWantsPrefetching = 1, |
| kStreamedFromLocalHost = 2, |
| kIsCachingDataSource = 4, |
| kIsHTTPBasedSource = 8, |
| kIsLocalFileSource = 16, |
| }; |
| |
| DataSourceBase() {} |
| |
| 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); |
| |
| // read either int<N> or int<2N> into a uint<2N>_t, size is the int size in bytes. |
| bool getUInt16Var(off64_t offset, uint16_t *x, size_t size); |
| bool getUInt32Var(off64_t offset, uint32_t *x, size_t size); |
| bool getUInt64Var(off64_t offset, uint64_t *x, size_t size); |
| |
| // May return ERROR_UNSUPPORTED. |
| virtual status_t getSize(off64_t *size); |
| |
| virtual bool getUri(char *uriString, size_t bufferSize); |
| |
| virtual uint32_t flags() { |
| return 0; |
| } |
| |
| virtual void close() {}; |
| |
| virtual status_t getAvailableSize(off64_t /*offset*/, off64_t * /*size*/) { |
| return -1; |
| } |
| |
| protected: |
| virtual ~DataSourceBase() {} |
| |
| private: |
| DataSourceBase(const DataSourceBase &); |
| DataSourceBase &operator=(const DataSourceBase &); |
| }; |
| |
| } // namespace android |
| |
| #endif // DATA_SOURCE_BASE_H_ |