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The official mbed C/C SDK provides the software platform and libraries to build your applications.

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FileHandle.h@64:75c1708b266b, 2013-07-05 (annotated)

Committer:
ldyz
Date:
Fri Jul 05 13:16:13 2013 +0000
Revision:
64:75c1708b266b
Parent:
59:0883845fe643 
test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 44:24d45a770a51 1 /* mbed Microcontroller Library
emilmont 54:71b101360fb9 2 * Copyright (c) 2006-2013 ARM Limited
emilmont 44:24d45a770a51 3 *
emilmont 59:0883845fe643 4 * Licensed under the Apache License, Version 2.0 (the "License");
emilmont 59:0883845fe643 5 * you may not use this file except in compliance with the License.
emilmont 59:0883845fe643 6 * You may obtain a copy of the License at
emilmont 59:0883845fe643 7 *
emilmont 59:0883845fe643 8 * http://www.apache.org/licenses/LICENSE-2.0
emilmont 44:24d45a770a51 9 *
emilmont 59:0883845fe643 10 * Unless required by applicable law or agreed to in writing, software
emilmont 59:0883845fe643 11 * distributed under the License is distributed on an "AS IS" BASIS,
emilmont 59:0883845fe643 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
emilmont 59:0883845fe643 13 * See the License for the specific language governing permissions and
emilmont 59:0883845fe643 14 * limitations under the License.
emilmont 44:24d45a770a51 15 */
simon.ford@mbed.co.uk 0:82220227f4fa 16 #ifndef MBED_FILEHANDLE_H
simon.ford@mbed.co.uk 0:82220227f4fa 17 #define MBED_FILEHANDLE_H
simon.ford@mbed.co.uk 0:82220227f4fa 18
simon.ford@mbed.co.uk 4:5d1359a283bc 19 typedef int FILEHANDLE;
simon.ford@mbed.co.uk 4:5d1359a283bc 20
simon.ford@mbed.co.uk 4:5d1359a283bc 21 #include <stdio.h>
emilmont 55:d722ed6a4237 22
emilmont 55:d722ed6a4237 23 #if defined(__ARMCC_VERSION) || defined(__ICCARM__)
simon.ford@mbed.co.uk 4:5d1359a283bc 24 typedef int ssize_t;
simon.ford@mbed.co.uk 4:5d1359a283bc 25 typedef long off_t;
emilmont 55:d722ed6a4237 26
simon.ford@mbed.co.uk 4:5d1359a283bc 27 #else
emilmont 55:d722ed6a4237 28 # include <sys/types.h>
simon.ford@mbed.co.uk 4:5d1359a283bc 29 #endif
simon.ford@mbed.co.uk 4:5d1359a283bc 30
emilmont 55:d722ed6a4237 31 namespace mbed {
simon.ford@mbed.co.uk 0:82220227f4fa 32
emilmont 43:e2ed12d17f06 33 /** An OO equivalent of the internal FILEHANDLE variable
emilmont 43:e2ed12d17f06 34 * and associated _sys_* functions.
simon.ford@mbed.co.uk 0:82220227f4fa 35 *
emilmont 44:24d45a770a51 36 * FileHandle is an abstract class, needing at least sys_write and
emilmont 43:e2ed12d17f06 37 * sys_read to be implmented for a simple interactive device.
simon.ford@mbed.co.uk 0:82220227f4fa 38 *
emilmont 55:d722ed6a4237 39 * No one ever directly tals to/instanciates a FileHandle - it gets
emilmont 43:e2ed12d17f06 40 * created by FileSystem, and wrapped up by stdio.
simon.ford@mbed.co.uk 0:82220227f4fa 41 */
simon.ford@mbed.co.uk 0:82220227f4fa 42 class FileHandle {
simon.ford@mbed.co.uk 0:82220227f4fa 43
simon.ford@mbed.co.uk 0:82220227f4fa 44 public:
emilmont 43:e2ed12d17f06 45 /** Write the contents of a buffer to the file
simon.ford@mbed.co.uk 0:82220227f4fa 46 *
emilmont 43:e2ed12d17f06 47 * @param buffer the buffer to write from
emilmont 43:e2ed12d17f06 48 * @param length the number of characters to write
simon.ford@mbed.co.uk 0:82220227f4fa 49 *
emilmont 43:e2ed12d17f06 50 * @returns
emilmont 44:24d45a770a51 51 * The number of characters written (possibly 0) on success, -1 on error.
simon.ford@mbed.co.uk 0:82220227f4fa 52 */
simon.ford@mbed.co.uk 4:5d1359a283bc 53 virtual ssize_t write(const void* buffer, size_t length) = 0;
simon.ford@mbed.co.uk 0:82220227f4fa 54
emilmont 43:e2ed12d17f06 55 /** Close the file
simon.ford@mbed.co.uk 4:5d1359a283bc 56 *
emilmont 43:e2ed12d17f06 57 * @returns
emilmont 44:24d45a770a51 58 * Zero on success, -1 on error.
simon.ford@mbed.co.uk 4:5d1359a283bc 59 */
simon.ford@mbed.co.uk 4:5d1359a283bc 60 virtual int close() = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 61
emilmont 43:e2ed12d17f06 62 /** Function read
simon.ford@mbed.co.uk 4:5d1359a283bc 63 * Reads the contents of the file into a buffer
simon.ford@mbed.co.uk 4:5d1359a283bc 64 *
emilmont 43:e2ed12d17f06 65 * @param buffer the buffer to read in to
emilmont 43:e2ed12d17f06 66 * @param length the number of characters to read
simon.ford@mbed.co.uk 0:82220227f4fa 67 *
emilmont 43:e2ed12d17f06 68 * @returns
emilmont 44:24d45a770a51 69 * The number of characters read (zero at end of file) on success, -1 on error.
simon.ford@mbed.co.uk 4:5d1359a283bc 70 */
simon.ford@mbed.co.uk 4:5d1359a283bc 71 virtual ssize_t read(void* buffer, size_t length) = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 72
emilmont 43:e2ed12d17f06 73 /** Check if the handle is for a interactive terminal device.
emilmont 44:24d45a770a51 74 * If so, line buffered behaviour is used by default
simon.ford@mbed.co.uk 4:5d1359a283bc 75 *
emilmont 43:e2ed12d17f06 76 * @returns
emilmont 43:e2ed12d17f06 77 * 1 if it is a terminal,
emilmont 43:e2ed12d17f06 78 * 0 otherwise
simon.ford@mbed.co.uk 4:5d1359a283bc 79 */
emilmont 44:24d45a770a51 80 virtual int isatty() = 0;
simon.ford@mbed.co.uk 0:82220227f4fa 81
emilmont 43:e2ed12d17f06 82 /** Move the file position to a given offset from a given location.
simon.ford@mbed.co.uk 4:5d1359a283bc 83 *
emilmont 43:e2ed12d17f06 84 * @param offset The offset from whence to move to
emilmont 43:e2ed12d17f06 85 * @param whence SEEK_SET for the start of the file, SEEK_CUR for the
simon.ford@mbed.co.uk 4:5d1359a283bc 86 * current file position, or SEEK_END for the end of the file.
simon.ford@mbed.co.uk 4:5d1359a283bc 87 *
emilmont 43:e2ed12d17f06 88 * @returns
emilmont 43:e2ed12d17f06 89 * new file position on success,
emilmont 43:e2ed12d17f06 90 * -1 on failure or unsupported
simon.ford@mbed.co.uk 4:5d1359a283bc 91 */
simon.ford@mbed.co.uk 4:5d1359a283bc 92 virtual off_t lseek(off_t offset, int whence) = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 93
emilmont 43:e2ed12d17f06 94 /** Flush any buffers associated with the FileHandle, ensuring it
simon.ford@mbed.co.uk 4:5d1359a283bc 95 * is up to date on disk
simon.ford@mbed.co.uk 4:5d1359a283bc 96 *
emilmont 43:e2ed12d17f06 97 * @returns
emilmont 43:e2ed12d17f06 98 * 0 on success or un-needed,
emilmont 43:e2ed12d17f06 99 * -1 on error
simon.ford@mbed.co.uk 4:5d1359a283bc 100 */
simon.ford@mbed.co.uk 4:5d1359a283bc 101 virtual int fsync() = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 102
simon.ford@mbed.co.uk 4:5d1359a283bc 103 virtual off_t flen() {
simon.ford@mbed.co.uk 4:5d1359a283bc 104 /* remember our current position */
simon.ford@mbed.co.uk 4:5d1359a283bc 105 off_t pos = lseek(0, SEEK_CUR);
simon.ford@mbed.co.uk 4:5d1359a283bc 106 if(pos == -1) return -1;
simon.ford@mbed.co.uk 4:5d1359a283bc 107 /* seek to the end to get the file length */
simon.ford@mbed.co.uk 4:5d1359a283bc 108 off_t res = lseek(0, SEEK_END);
simon.ford@mbed.co.uk 4:5d1359a283bc 109 /* return to our old position */
simon.ford@mbed.co.uk 4:5d1359a283bc 110 lseek(pos, SEEK_SET);
simon.ford@mbed.co.uk 4:5d1359a283bc 111 return res;
simon.ford@mbed.co.uk 4:5d1359a283bc 112 }
emilmont 55:d722ed6a4237 113
emilmont 44:24d45a770a51 114 virtual ~FileHandle();
simon.ford@mbed.co.uk 0:82220227f4fa 115 };
simon.ford@mbed.co.uk 0:82220227f4fa 116
simon.ford@mbed.co.uk 0:82220227f4fa 117 } // namespace mbed
simon.ford@mbed.co.uk 0:82220227f4fa 118
simon.ford@mbed.co.uk 1:6b7f447ca868 119 #endif