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File.h
1 /* mbed Microcontroller Library
2  * Copyright (c) 2015 ARM Limited
3  * SPDX-License-Identifier: Apache-2.0
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 #ifndef FILE_H
19 #define FILE_H
20 
21 #include "filesystem/FileSystem.h"
22 #include "platform/FileHandle.h"
23 
24 namespace mbed {
25 /** \addtogroup filesystem */
26 /** @{*/
27 
28 
29 /** File class
30  */
31 class File : public FileHandle {
32 public:
33  /** Create an uninitialized file
34  *
35  * Must call open to initialize the file on a file system
36  */
37  File();
38 
39  /** Create a file on a filesystem
40  *
41  * Creates and opens a file on a filesystem
42  *
43  * @param fs Filesystem as target for the file
44  * @param path The name of the file to open
45  * @param flags The flags to open the file in, one of O_RDONLY, O_WRONLY, O_RDWR,
46  * bitwise or'd with one of O_CREAT, O_TRUNC, O_APPEND
47  */
48  File(FileSystem *fs, const char *path, int flags = O_RDONLY);
49 
50  /** Destroy a file
51  *
52  * Closes file if the file is still open
53  */
54  virtual ~File();
55 
56  /** Open a file on the filesystem
57  *
58  * @param fs Filesystem as target for the file
59  * @param path The name of the file to open
60  * @param flags The flags to open the file in, one of O_RDONLY, O_WRONLY, O_RDWR,
61  * bitwise or'd with one of O_CREAT, O_TRUNC, O_APPEND
62  * @return 0 on success, negative error code on failure
63  */
64  virtual int open(FileSystem *fs, const char *path, int flags = O_RDONLY);
65 
66  /** Close a file
67  *
68  * @return 0 on success, negative error code on failure
69  */
70  virtual int close();
71 
72  /** Read the contents of a file into a buffer
73  *
74  * @param buffer The buffer to read in to
75  * @param size The number of bytes to read
76  * @return The number of bytes read, 0 at end of file, negative error on failure
77  */
78 
79  virtual ssize_t read(void *buffer, size_t size);
80 
81  /** Write the contents of a buffer to a file
82  *
83  * @param buffer The buffer to write from
84  * @param size The number of bytes to write
85  * @return The number of bytes written, negative error on failure
86  */
87  virtual ssize_t write(const void *buffer, size_t size);
88 
89  /** Flush any buffers associated with the file
90  *
91  * @return 0 on success, negative error code on failure
92  */
93  virtual int sync();
94 
95  /** Check if the file in an interactive terminal device
96  *
97  * @return True if the file is a terminal
98  */
99  virtual int isatty();
100 
101  /** Move the file position to a given offset from from a given location
102  *
103  * @param offset The offset from whence to move to
104  * @param whence The start of where to seek
105  * SEEK_SET to start from beginning of file,
106  * SEEK_CUR to start from current position in file,
107  * SEEK_END to start from end of file
108  * @return The new offset of the file
109  */
110  virtual off_t seek(off_t offset, int whence = SEEK_SET);
111 
112  /** Get the file position of the file
113  *
114  * @return The current offset in the file
115  */
116  virtual off_t tell();
117 
118  /** Rewind the file position to the beginning of the file
119  *
120  * @note This is equivalent to file_seek(file, 0, FS_SEEK_SET)
121  */
122  virtual void rewind();
123 
124  /** Get the size of the file
125  *
126  * @return Size of the file in bytes
127  */
128  virtual off_t size();
129 
130  /** Truncate or extend a file.
131  *
132  * The file's length is set to the specified value. The seek pointer is
133  * not changed. If the file is extended, the extended area appears as if
134  * it were zero-filled.
135  *
136  * @param length The requested new length for the file
137  *
138  * @return Zero on success, negative error code on failure
139  */
140  virtual int truncate(off_t length);
141 
142 private:
143  FileSystem *_fs;
144  fs_file_t _file;
145 };
146 
147 
148 /** @}*/
149 } // namespace mbed
150 
151 #endif
mbed::File::~File
virtual ~File()
Destroy a file.
mbed::File::truncate
virtual int truncate(off_t length)
Truncate or extend a file.
mbed::File::sync
virtual int sync()
Flush any buffers associated with the file.
mbed::FileHandle
Class FileHandle.
Definition: FileHandle.h:46
mbed::File::isatty
virtual int isatty()
Check if the file in an interactive terminal device.
mbed::File::rewind
virtual void rewind()
Rewind the file position to the beginning of the file.
mbed::File::size
virtual off_t size()
Get the size of the file.
mbed::File::open
virtual int open(FileSystem *fs, const char *path, int flags=O_RDONLY)
Open a file on the filesystem.
mbed::File
File class.
Definition: File.h:31
mbed::FileSystem
A file system object.
Definition: FileSystem.h:50
mbed::File::read
virtual ssize_t read(void *buffer, size_t size)
Read the contents of a file into a buffer.
mbed::File::File
File()
Create an uninitialized file.
mbed::File::close
virtual int close()
Close a file.
mbed::File::seek
virtual off_t seek(off_t offset, int whence=SEEK_SET)
Move the file position to a given offset from from a given location.
mbed
Definition: ATHandler.h:46
mbed::File::write
virtual ssize_t write(const void *buffer, size_t size)
Write the contents of a buffer to a file.
mbed::File::tell
virtual off_t tell()
Get the file position of the file.
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