| // Copyright 2015 The Chromium OS Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef _BSDIFF_FILE_INTERFACE_H_ |
| #define _BSDIFF_FILE_INTERFACE_H_ |
| |
| #include <sys/types.h> |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include "bsdiff/common.h" |
| |
| static_assert(sizeof(off_t) == sizeof(int64_t), |
| "off_t must be a 64-bit number, use -D_FILE_OFFSET_BITS=64"); |
| |
| namespace bsdiff { |
| |
| class BSDIFF_EXPORT FileInterface { |
| public: |
| virtual ~FileInterface() = default; |
| |
| // Reads synchronously from the current file position up to |count| bytes into |
| // the passed |buf| buffer. On success, stores in |bytes_read| how many bytes |
| // were actually read from the file. In case of error returns false. This |
| // method may read less than |count| bytes even if there's no error. If the |
| // end of file is reached, 0 bytes will be read and this methods returns true. |
| virtual bool Read(void* buf, size_t count, size_t* bytes_read) = 0; |
| |
| // Writes synchronously up to |count| bytes from to passed |buf| buffer to |
| // the file. On success, stores in |bytes_written| how many bytes |
| // were actually written to the file. This method may write less than |count| |
| // bytes and return successfully, or even write 0 bytes if there's no more |
| // space left on the device. Returns whether the write succeeded. |
| virtual bool Write(const void* buf, size_t count, size_t* bytes_written) = 0; |
| |
| // Change the current file position to |pos| bytes from the beginning of the |
| // file. Return whether the seek succeeded. |
| virtual bool Seek(off_t pos) = 0; |
| |
| // Closes the file and flushes any cached data. Returns whether the close |
| // succeeded. |
| virtual bool Close() = 0; |
| |
| // Compute the size of the file and store it in |size|. Returns whether it |
| // computed the size successfully. |
| virtual bool GetSize(uint64_t* size) = 0; |
| |
| protected: |
| FileInterface() = default; |
| }; |
| |
| } // namespace bsdiff |
| |
| #endif // _BSDIFF_FILE_INTERFACE_H_ |