Juan Salazar / mbed

test

Dependents:   robotic_fish_7

FileHandle.h@0:44931ff4a3ed, 2020-01-14 (annotated)

Committer:
juansal12
Date:
Tue Jan 14 19:14:29 2020 +0000
Revision:
0:44931ff4a3ed
Sofi 7 code;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
juansal12 0:44931ff4a3ed 1 /* mbed Microcontroller Library
juansal12 0:44931ff4a3ed 2 * Copyright (c) 2006-2013 ARM Limited
juansal12 0:44931ff4a3ed 3 *
juansal12 0:44931ff4a3ed 4 * Licensed under the Apache License, Version 2.0 (the "License");
juansal12 0:44931ff4a3ed 5 * you may not use this file except in compliance with the License.
juansal12 0:44931ff4a3ed 6 * You may obtain a copy of the License at
juansal12 0:44931ff4a3ed 7 *
juansal12 0:44931ff4a3ed 8 * http://www.apache.org/licenses/LICENSE-2.0
juansal12 0:44931ff4a3ed 9 *
juansal12 0:44931ff4a3ed 10 * Unless required by applicable law or agreed to in writing, software
juansal12 0:44931ff4a3ed 11 * distributed under the License is distributed on an "AS IS" BASIS,
juansal12 0:44931ff4a3ed 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
juansal12 0:44931ff4a3ed 13 * See the License for the specific language governing permissions and
juansal12 0:44931ff4a3ed 14 * limitations under the License.
juansal12 0:44931ff4a3ed 15 */
juansal12 0:44931ff4a3ed 16 #ifndef MBED_FILEHANDLE_H
juansal12 0:44931ff4a3ed 17 #define MBED_FILEHANDLE_H
juansal12 0:44931ff4a3ed 18
juansal12 0:44931ff4a3ed 19 typedef int FILEHANDLE;
juansal12 0:44931ff4a3ed 20
juansal12 0:44931ff4a3ed 21 #include <stdio.h>
juansal12 0:44931ff4a3ed 22
juansal12 0:44931ff4a3ed 23 #if defined(__ARMCC_VERSION) || defined(__ICCARM__)
juansal12 0:44931ff4a3ed 24 typedef int ssize_t;
juansal12 0:44931ff4a3ed 25 typedef long off_t;
juansal12 0:44931ff4a3ed 26
juansal12 0:44931ff4a3ed 27 #else
juansal12 0:44931ff4a3ed 28 # include <sys/types.h>
juansal12 0:44931ff4a3ed 29 #endif
juansal12 0:44931ff4a3ed 30
juansal12 0:44931ff4a3ed 31 namespace mbed {
juansal12 0:44931ff4a3ed 32
juansal12 0:44931ff4a3ed 33 /** An OO equivalent of the internal FILEHANDLE variable
juansal12 0:44931ff4a3ed 34 * and associated _sys_* functions.
juansal12 0:44931ff4a3ed 35 *
juansal12 0:44931ff4a3ed 36 * FileHandle is an abstract class, needing at least sys_write and
juansal12 0:44931ff4a3ed 37 * sys_read to be implmented for a simple interactive device.
juansal12 0:44931ff4a3ed 38 *
juansal12 0:44931ff4a3ed 39 * No one ever directly tals to/instanciates a FileHandle - it gets
juansal12 0:44931ff4a3ed 40 * created by FileSystem, and wrapped up by stdio.
juansal12 0:44931ff4a3ed 41 */
juansal12 0:44931ff4a3ed 42 class FileHandle {
juansal12 0:44931ff4a3ed 43
juansal12 0:44931ff4a3ed 44 public:
juansal12 0:44931ff4a3ed 45 /** Write the contents of a buffer to the file
juansal12 0:44931ff4a3ed 46 *
juansal12 0:44931ff4a3ed 47 * @param buffer the buffer to write from
juansal12 0:44931ff4a3ed 48 * @param length the number of characters to write
juansal12 0:44931ff4a3ed 49 *
juansal12 0:44931ff4a3ed 50 * @returns
juansal12 0:44931ff4a3ed 51 * The number of characters written (possibly 0) on success, -1 on error.
juansal12 0:44931ff4a3ed 52 */
juansal12 0:44931ff4a3ed 53 virtual ssize_t write(const void* buffer, size_t length) = 0;
juansal12 0:44931ff4a3ed 54
juansal12 0:44931ff4a3ed 55 /** Close the file
juansal12 0:44931ff4a3ed 56 *
juansal12 0:44931ff4a3ed 57 * @returns
juansal12 0:44931ff4a3ed 58 * Zero on success, -1 on error.
juansal12 0:44931ff4a3ed 59 */
juansal12 0:44931ff4a3ed 60 virtual int close() = 0;
juansal12 0:44931ff4a3ed 61
juansal12 0:44931ff4a3ed 62 /** Function read
juansal12 0:44931ff4a3ed 63 * Reads the contents of the file into a buffer
juansal12 0:44931ff4a3ed 64 *
juansal12 0:44931ff4a3ed 65 * @param buffer the buffer to read in to
juansal12 0:44931ff4a3ed 66 * @param length the number of characters to read
juansal12 0:44931ff4a3ed 67 *
juansal12 0:44931ff4a3ed 68 * @returns
juansal12 0:44931ff4a3ed 69 * The number of characters read (zero at end of file) on success, -1 on error.
juansal12 0:44931ff4a3ed 70 */
juansal12 0:44931ff4a3ed 71 virtual ssize_t read(void* buffer, size_t length) = 0;
juansal12 0:44931ff4a3ed 72
juansal12 0:44931ff4a3ed 73 /** Check if the handle is for a interactive terminal device.
juansal12 0:44931ff4a3ed 74 * If so, line buffered behaviour is used by default
juansal12 0:44931ff4a3ed 75 *
juansal12 0:44931ff4a3ed 76 * @returns
juansal12 0:44931ff4a3ed 77 * 1 if it is a terminal,
juansal12 0:44931ff4a3ed 78 * 0 otherwise
juansal12 0:44931ff4a3ed 79 */
juansal12 0:44931ff4a3ed 80 virtual int isatty() = 0;
juansal12 0:44931ff4a3ed 81
juansal12 0:44931ff4a3ed 82 /** Move the file position to a given offset from a given location.
juansal12 0:44931ff4a3ed 83 *
juansal12 0:44931ff4a3ed 84 * @param offset The offset from whence to move to
juansal12 0:44931ff4a3ed 85 * @param whence SEEK_SET for the start of the file, SEEK_CUR for the
juansal12 0:44931ff4a3ed 86 * current file position, or SEEK_END for the end of the file.
juansal12 0:44931ff4a3ed 87 *
juansal12 0:44931ff4a3ed 88 * @returns
juansal12 0:44931ff4a3ed 89 * new file position on success,
juansal12 0:44931ff4a3ed 90 * -1 on failure or unsupported
juansal12 0:44931ff4a3ed 91 */
juansal12 0:44931ff4a3ed 92 virtual off_t lseek(off_t offset, int whence) = 0;
juansal12 0:44931ff4a3ed 93
juansal12 0:44931ff4a3ed 94 /** Flush any buffers associated with the FileHandle, ensuring it
juansal12 0:44931ff4a3ed 95 * is up to date on disk
juansal12 0:44931ff4a3ed 96 *
juansal12 0:44931ff4a3ed 97 * @returns
juansal12 0:44931ff4a3ed 98 * 0 on success or un-needed,
juansal12 0:44931ff4a3ed 99 * -1 on error
juansal12 0:44931ff4a3ed 100 */
juansal12 0:44931ff4a3ed 101 virtual int fsync() = 0;
juansal12 0:44931ff4a3ed 102
juansal12 0:44931ff4a3ed 103 virtual off_t flen() {
juansal12 0:44931ff4a3ed 104 /* remember our current position */
juansal12 0:44931ff4a3ed 105 off_t pos = lseek(0, SEEK_CUR);
juansal12 0:44931ff4a3ed 106 if(pos == -1) return -1;
juansal12 0:44931ff4a3ed 107 /* seek to the end to get the file length */
juansal12 0:44931ff4a3ed 108 off_t res = lseek(0, SEEK_END);
juansal12 0:44931ff4a3ed 109 /* return to our old position */
juansal12 0:44931ff4a3ed 110 lseek(pos, SEEK_SET);
juansal12 0:44931ff4a3ed 111 return res;
juansal12 0:44931ff4a3ed 112 }
juansal12 0:44931ff4a3ed 113
juansal12 0:44931ff4a3ed 114 virtual ~FileHandle();
juansal12 0:44931ff4a3ed 115 };
juansal12 0:44931ff4a3ed 116
juansal12 0:44931ff4a3ed 117 } // namespace mbed
juansal12 0:44931ff4a3ed 118
juansal12 0:44931ff4a3ed 119 #endif