chfiles.h
5.62 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011,2012 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
---
A special exception to the GPL can be applied should you wish to distribute
a combined work that includes ChibiOS/RT, without being obliged to provide
the source code for any proprietary components. See the file exception.txt
for full details of how and when the exception can be applied.
*/
/**
* @file chfiles.h
* @brief Data files.
* @details This header defines abstract interfaces useful to access generic
* data files in a standardized way.
*
* @addtogroup data_files
* @details This module define an abstract interface for generic data files by
* extending the @p BaseSequentialStream interface. Note that no code
* is present, data files are just abstract interface-like structures,
* you should look at the systems as to a set of abstract C++ classes
* (even if written in C). This system has the advantage to make the
* access to streams independent from the implementation logic.<br>
* The data files interface can be used as base class for high level
* object types such as an API for a File System implementation.
* @{
*/
#ifndef _CHFILES_H_
#define _CHFILES_H_
/**
* @brief No error return code.
*/
#define FILE_OK 0
/**
* @brief Error code from the file stream methods.
*/
#define FILE_ERROR 0xFFFFFFFFUL
/**
* @brief File offset type.
*/
typedef uint32_t fileoffset_t;
/**
* @brief BaseFileStream specific methods.
*/
#define _base_file_stream_methods \
_base_sequential_stream_methods \
/* File close method.*/ \
uint32_t (*close)(void *instance); \
/* Get last error code method.*/ \
int (*geterror)(void *instance); \
/* File get size method.*/ \
fileoffset_t (*getsize)(void *instance); \
/* File get current position method.*/ \
fileoffset_t (*getposition)(void *instance); \
/* File seek method.*/ \
uint32_t (*lseek)(void *instance, fileoffset_t offset);
/**
* @brief @p BaseFileStream specific data.
* @note It is empty because @p BaseFileStream is only an interface
* without implementation.
*/
#define _base_file_stream_data \
_base_sequential_stream_data
/**
* @extends BaseSequentialStreamVMT
*
* @brief @p BaseFileStream virtual methods table.
*/
struct BaseFileStreamVMT {
_base_file_stream_methods
};
/**
* @extends BaseSequentialStream
*
* @brief Base file stream class.
* @details This class represents a generic file data stream.
*/
typedef struct {
/** @brief Virtual Methods Table.*/
const struct BaseFileStreamVMT *vmt;
_base_file_stream_data
} BaseFileStream;
/**
* @name Macro Functions (BaseFileStream)
* @{
*/
/**
* @brief Base file Stream close.
* @details The function closes a file stream.
*
* @param[in] ip pointer to a @p BaseFileStream or derived class
* @return The operation status.
* @retval FILE_OK no error.
* @retval FILE_ERROR operation failed.
*
* @api
*/
#define chFileStreamClose(ip) ((ip)->vmt->close(ip))
/**
* @brief Returns an implementation dependent error code.
*
* @param[in] ip pointer to a @p BaseFileStream or derived class
* @return Implementation dependent error code.
*
* @api
*/
#define chFileStreamGetError(ip) ((ip)->vmt->geterror(ip))
/**
* @brief Returns the current file size.
*
* @param[in] ip pointer to a @p BaseFileStream or derived class
* @return The file size.
*
* @api
*/
#define chFileStreamGetSize(ip) ((ip)->vmt->getsize(ip))
/**
* @brief Returns the current file pointer position.
*
* @param[in] ip pointer to a @p BaseFileStream or derived class
* @return The current position inside the file.
*
* @api
*/
#define chFileStreamGetPosition(ip) ((ip)->vmt->getposition(ip))
/**
* @brief Moves the file current pointer to an absolute position.
*
* @param[in] ip pointer to a @p BaseFileStream or derived class
* @param[in] offset new absolute position
* @return The operation status.
* @retval FILE_OK no error.
* @retval FILE_ERROR operation failed.
*
* @api
*/
#define chFileStreamSeek(ip, offset) ((ip)->vmt->lseek(ip, offset))
/** @} */
#endif /* _CHFILES_H_ */
/** @} */