1 /*****************************************************************************
2 * Author: Valient Gough <vgough@pobox.com>
3 *
4 *****************************************************************************
5 * Copyright (c) 2004, Valient Gough
6 *
7 * This program is free software: you can redistribute it and/or modify it
8 * under the terms of the GNU Lesser General Public License as published by the
9 * Free Software Foundation, either version 3 of the License, or (at your
10 * option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public License
18 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #ifndef _FileIO_incl_
22 #define _FileIO_incl_
23
24 #include <inttypes.h>
25 #include <stdint.h>
26 #include <sys/types.h>
27
28 #include "Interface.h"
29 #include "encfs.h"
30
31 namespace encfs {
32
33 struct IORequest {
34 off_t offset;
35
36 // amount of bytes to read/write.
37 size_t dataLen;
38 unsigned char *data;
39
40 IORequest();
41 };
42
IORequest()43 inline IORequest::IORequest() : offset(0), dataLen(0), data(0) {}
44
45 class FileIO {
46 public:
47 FileIO();
48 virtual ~FileIO();
49
50 virtual Interface interface() const = 0;
51
52 // default implementation returns 1, meaning this is not block oriented.
53 virtual unsigned int blockSize() const;
54
55 virtual void setFileName(const char *fileName) = 0;
56 virtual const char *getFileName() const = 0;
57
58 // Not sure about this -- it is specific to CipherFileIO, but the
59 // alternative methods of exposing this interface aren't much nicer..
60 virtual bool setIV(uint64_t iv);
61
62 // open file for specified mode. There is no corresponding close, so a
63 // file is open until the FileIO interface is destroyed.
64 virtual int open(int flags) = 0;
65
66 // get filesystem attributes for a file
67 virtual int getAttr(struct stat *stbuf) const = 0;
68 virtual off_t getSize() const = 0;
69
70 virtual ssize_t read(const IORequest &req) const = 0;
71 virtual ssize_t write(const IORequest &req) = 0;
72
73 virtual int truncate(off_t size) = 0;
74
75 virtual bool isWritable() const = 0;
76
77 private:
78 // not implemented..
79 FileIO(const FileIO &);
80 FileIO &operator=(const FileIO &);
81 };
82
83 } // namespace encfs
84
85 #endif
86