Tomo Yamanaka / mbed-dev

mbed library sources. Supersedes mbed-src. GR-PEACH runs on RAM.

Fork of mbed-dev by mbed official

api/FileHandle.h@0:9b334a45a8ff, 2015-10-01 (annotated)

Committer:
bogdanm
Date:
Thu Oct 01 15:25:22 2015 +0300
Revision:
0:9b334a45a8ff
Initial commit on mbed-dev



Replaces mbed-src (now inactive)

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #ifndef MBED_FILEHANDLE_H
bogdanm 0:9b334a45a8ff 17 #define MBED_FILEHANDLE_H
bogdanm 0:9b334a45a8ff 18
bogdanm 0:9b334a45a8ff 19 typedef int FILEHANDLE;
bogdanm 0:9b334a45a8ff 20
bogdanm 0:9b334a45a8ff 21 #include <stdio.h>
bogdanm 0:9b334a45a8ff 22
bogdanm 0:9b334a45a8ff 23 #if defined(__ARMCC_VERSION) || defined(__ICCARM__)
bogdanm 0:9b334a45a8ff 24 typedef int ssize_t;
bogdanm 0:9b334a45a8ff 25 typedef long off_t;
bogdanm 0:9b334a45a8ff 26
bogdanm 0:9b334a45a8ff 27 #else
bogdanm 0:9b334a45a8ff 28 # include <sys/types.h>
bogdanm 0:9b334a45a8ff 29 #endif
bogdanm 0:9b334a45a8ff 30
bogdanm 0:9b334a45a8ff 31 namespace mbed {
bogdanm 0:9b334a45a8ff 32
bogdanm 0:9b334a45a8ff 33 /** An OO equivalent of the internal FILEHANDLE variable
bogdanm 0:9b334a45a8ff 34 * and associated _sys_* functions.
bogdanm 0:9b334a45a8ff 35 *
bogdanm 0:9b334a45a8ff 36 * FileHandle is an abstract class, needing at least sys_write and
bogdanm 0:9b334a45a8ff 37 * sys_read to be implmented for a simple interactive device.
bogdanm 0:9b334a45a8ff 38 *
bogdanm 0:9b334a45a8ff 39 * No one ever directly tals to/instanciates a FileHandle - it gets
bogdanm 0:9b334a45a8ff 40 * created by FileSystem, and wrapped up by stdio.
bogdanm 0:9b334a45a8ff 41 */
bogdanm 0:9b334a45a8ff 42 class FileHandle {
bogdanm 0:9b334a45a8ff 43
bogdanm 0:9b334a45a8ff 44 public:
bogdanm 0:9b334a45a8ff 45 /** Write the contents of a buffer to the file
bogdanm 0:9b334a45a8ff 46 *
bogdanm 0:9b334a45a8ff 47 * @param buffer the buffer to write from
bogdanm 0:9b334a45a8ff 48 * @param length the number of characters to write
bogdanm 0:9b334a45a8ff 49 *
bogdanm 0:9b334a45a8ff 50 * @returns
bogdanm 0:9b334a45a8ff 51 * The number of characters written (possibly 0) on success, -1 on error.
bogdanm 0:9b334a45a8ff 52 */
bogdanm 0:9b334a45a8ff 53 virtual ssize_t write(const void* buffer, size_t length) = 0;
bogdanm 0:9b334a45a8ff 54
bogdanm 0:9b334a45a8ff 55 /** Close the file
bogdanm 0:9b334a45a8ff 56 *
bogdanm 0:9b334a45a8ff 57 * @returns
bogdanm 0:9b334a45a8ff 58 * Zero on success, -1 on error.
bogdanm 0:9b334a45a8ff 59 */
bogdanm 0:9b334a45a8ff 60 virtual int close() = 0;
bogdanm 0:9b334a45a8ff 61
bogdanm 0:9b334a45a8ff 62 /** Function read
bogdanm 0:9b334a45a8ff 63 * Reads the contents of the file into a buffer
bogdanm 0:9b334a45a8ff 64 *
bogdanm 0:9b334a45a8ff 65 * @param buffer the buffer to read in to
bogdanm 0:9b334a45a8ff 66 * @param length the number of characters to read
bogdanm 0:9b334a45a8ff 67 *
bogdanm 0:9b334a45a8ff 68 * @returns
bogdanm 0:9b334a45a8ff 69 * The number of characters read (zero at end of file) on success, -1 on error.
bogdanm 0:9b334a45a8ff 70 */
bogdanm 0:9b334a45a8ff 71 virtual ssize_t read(void* buffer, size_t length) = 0;
bogdanm 0:9b334a45a8ff 72
bogdanm 0:9b334a45a8ff 73 /** Check if the handle is for a interactive terminal device.
bogdanm 0:9b334a45a8ff 74 * If so, line buffered behaviour is used by default
bogdanm 0:9b334a45a8ff 75 *
bogdanm 0:9b334a45a8ff 76 * @returns
bogdanm 0:9b334a45a8ff 77 * 1 if it is a terminal,
bogdanm 0:9b334a45a8ff 78 * 0 otherwise
bogdanm 0:9b334a45a8ff 79 */
bogdanm 0:9b334a45a8ff 80 virtual int isatty() = 0;
bogdanm 0:9b334a45a8ff 81
bogdanm 0:9b334a45a8ff 82 /** Move the file position to a given offset from a given location.
bogdanm 0:9b334a45a8ff 83 *
bogdanm 0:9b334a45a8ff 84 * @param offset The offset from whence to move to
bogdanm 0:9b334a45a8ff 85 * @param whence SEEK_SET for the start of the file, SEEK_CUR for the
bogdanm 0:9b334a45a8ff 86 * current file position, or SEEK_END for the end of the file.
bogdanm 0:9b334a45a8ff 87 *
bogdanm 0:9b334a45a8ff 88 * @returns
bogdanm 0:9b334a45a8ff 89 * new file position on success,
bogdanm 0:9b334a45a8ff 90 * -1 on failure or unsupported
bogdanm 0:9b334a45a8ff 91 */
bogdanm 0:9b334a45a8ff 92 virtual off_t lseek(off_t offset, int whence) = 0;
bogdanm 0:9b334a45a8ff 93
bogdanm 0:9b334a45a8ff 94 /** Flush any buffers associated with the FileHandle, ensuring it
bogdanm 0:9b334a45a8ff 95 * is up to date on disk
bogdanm 0:9b334a45a8ff 96 *
bogdanm 0:9b334a45a8ff 97 * @returns
bogdanm 0:9b334a45a8ff 98 * 0 on success or un-needed,
bogdanm 0:9b334a45a8ff 99 * -1 on error
bogdanm 0:9b334a45a8ff 100 */
bogdanm 0:9b334a45a8ff 101 virtual int fsync() = 0;
bogdanm 0:9b334a45a8ff 102
bogdanm 0:9b334a45a8ff 103 virtual off_t flen() {
bogdanm 0:9b334a45a8ff 104 /* remember our current position */
bogdanm 0:9b334a45a8ff 105 off_t pos = lseek(0, SEEK_CUR);
bogdanm 0:9b334a45a8ff 106 if(pos == -1) return -1;
bogdanm 0:9b334a45a8ff 107 /* seek to the end to get the file length */
bogdanm 0:9b334a45a8ff 108 off_t res = lseek(0, SEEK_END);
bogdanm 0:9b334a45a8ff 109 /* return to our old position */
bogdanm 0:9b334a45a8ff 110 lseek(pos, SEEK_SET);
bogdanm 0:9b334a45a8ff 111 return res;
bogdanm 0:9b334a45a8ff 112 }
bogdanm 0:9b334a45a8ff 113
bogdanm 0:9b334a45a8ff 114 virtual ~FileHandle();
bogdanm 0:9b334a45a8ff 115 };
bogdanm 0:9b334a45a8ff 116
bogdanm 0:9b334a45a8ff 117 } // namespace mbed
bogdanm 0:9b334a45a8ff 118
bogdanm 0:9b334a45a8ff 119 #endif