Ermanno Brusadin / mbed

mbed library sources

Dependents:   FRDM-KL46Z_LCD_Test FRDM-KL46Z_LCD_Test FRDM-KL46Z_Plantilla FRDM-KL46Z_Plantilla ... more

api/FileHandle.h@0:6bc4ac881c8e, 2016-07-28 (annotated)

Committer:
ebrus
Date:
Thu Jul 28 15:56:34 2016 +0000
Revision:
0:6bc4ac881c8e
1;

Who changed what in which revision?

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ebrus 0:6bc4ac881c8e 1 /* mbed Microcontroller Library
ebrus 0:6bc4ac881c8e 2 * Copyright (c) 2006-2013 ARM Limited
ebrus 0:6bc4ac881c8e 3 *
ebrus 0:6bc4ac881c8e 4 * Licensed under the Apache License, Version 2.0 (the "License");
ebrus 0:6bc4ac881c8e 5 * you may not use this file except in compliance with the License.
ebrus 0:6bc4ac881c8e 6 * You may obtain a copy of the License at
ebrus 0:6bc4ac881c8e 7 *
ebrus 0:6bc4ac881c8e 8 * http://www.apache.org/licenses/LICENSE-2.0
ebrus 0:6bc4ac881c8e 9 *
ebrus 0:6bc4ac881c8e 10 * Unless required by applicable law or agreed to in writing, software
ebrus 0:6bc4ac881c8e 11 * distributed under the License is distributed on an "AS IS" BASIS,
ebrus 0:6bc4ac881c8e 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
ebrus 0:6bc4ac881c8e 13 * See the License for the specific language governing permissions and
ebrus 0:6bc4ac881c8e 14 * limitations under the License.
ebrus 0:6bc4ac881c8e 15 */
ebrus 0:6bc4ac881c8e 16 #ifndef MBED_FILEHANDLE_H
ebrus 0:6bc4ac881c8e 17 #define MBED_FILEHANDLE_H
ebrus 0:6bc4ac881c8e 18
ebrus 0:6bc4ac881c8e 19 typedef int FILEHANDLE;
ebrus 0:6bc4ac881c8e 20
ebrus 0:6bc4ac881c8e 21 #include <stdio.h>
ebrus 0:6bc4ac881c8e 22
ebrus 0:6bc4ac881c8e 23 #if defined(__ARMCC_VERSION) || defined(__ICCARM__)
ebrus 0:6bc4ac881c8e 24 typedef int ssize_t;
ebrus 0:6bc4ac881c8e 25 typedef long off_t;
ebrus 0:6bc4ac881c8e 26
ebrus 0:6bc4ac881c8e 27 #else
ebrus 0:6bc4ac881c8e 28 # include <sys/types.h>
ebrus 0:6bc4ac881c8e 29 #endif
ebrus 0:6bc4ac881c8e 30
ebrus 0:6bc4ac881c8e 31 namespace mbed {
ebrus 0:6bc4ac881c8e 32
ebrus 0:6bc4ac881c8e 33 /** An OO equivalent of the internal FILEHANDLE variable
ebrus 0:6bc4ac881c8e 34 * and associated _sys_* functions.
ebrus 0:6bc4ac881c8e 35 *
ebrus 0:6bc4ac881c8e 36 * FileHandle is an abstract class, needing at least sys_write and
ebrus 0:6bc4ac881c8e 37 * sys_read to be implmented for a simple interactive device.
ebrus 0:6bc4ac881c8e 38 *
ebrus 0:6bc4ac881c8e 39 * No one ever directly tals to/instanciates a FileHandle - it gets
ebrus 0:6bc4ac881c8e 40 * created by FileSystem, and wrapped up by stdio.
ebrus 0:6bc4ac881c8e 41 */
ebrus 0:6bc4ac881c8e 42 class FileHandle {
ebrus 0:6bc4ac881c8e 43
ebrus 0:6bc4ac881c8e 44 public:
ebrus 0:6bc4ac881c8e 45 /** Write the contents of a buffer to the file
ebrus 0:6bc4ac881c8e 46 *
ebrus 0:6bc4ac881c8e 47 * @param buffer the buffer to write from
ebrus 0:6bc4ac881c8e 48 * @param length the number of characters to write
ebrus 0:6bc4ac881c8e 49 *
ebrus 0:6bc4ac881c8e 50 * @returns
ebrus 0:6bc4ac881c8e 51 * The number of characters written (possibly 0) on success, -1 on error.
ebrus 0:6bc4ac881c8e 52 */
ebrus 0:6bc4ac881c8e 53 virtual ssize_t write(const void* buffer, size_t length) = 0;
ebrus 0:6bc4ac881c8e 54
ebrus 0:6bc4ac881c8e 55 /** Close the file
ebrus 0:6bc4ac881c8e 56 *
ebrus 0:6bc4ac881c8e 57 * @returns
ebrus 0:6bc4ac881c8e 58 * Zero on success, -1 on error.
ebrus 0:6bc4ac881c8e 59 */
ebrus 0:6bc4ac881c8e 60 virtual int close() = 0;
ebrus 0:6bc4ac881c8e 61
ebrus 0:6bc4ac881c8e 62 /** Function read
ebrus 0:6bc4ac881c8e 63 * Reads the contents of the file into a buffer
ebrus 0:6bc4ac881c8e 64 *
ebrus 0:6bc4ac881c8e 65 * @param buffer the buffer to read in to
ebrus 0:6bc4ac881c8e 66 * @param length the number of characters to read
ebrus 0:6bc4ac881c8e 67 *
ebrus 0:6bc4ac881c8e 68 * @returns
ebrus 0:6bc4ac881c8e 69 * The number of characters read (zero at end of file) on success, -1 on error.
ebrus 0:6bc4ac881c8e 70 */
ebrus 0:6bc4ac881c8e 71 virtual ssize_t read(void* buffer, size_t length) = 0;
ebrus 0:6bc4ac881c8e 72
ebrus 0:6bc4ac881c8e 73 /** Check if the handle is for a interactive terminal device.
ebrus 0:6bc4ac881c8e 74 * If so, line buffered behaviour is used by default
ebrus 0:6bc4ac881c8e 75 *
ebrus 0:6bc4ac881c8e 76 * @returns
ebrus 0:6bc4ac881c8e 77 * 1 if it is a terminal,
ebrus 0:6bc4ac881c8e 78 * 0 otherwise
ebrus 0:6bc4ac881c8e 79 */
ebrus 0:6bc4ac881c8e 80 virtual int isatty() = 0;
ebrus 0:6bc4ac881c8e 81
ebrus 0:6bc4ac881c8e 82 /** Move the file position to a given offset from a given location.
ebrus 0:6bc4ac881c8e 83 *
ebrus 0:6bc4ac881c8e 84 * @param offset The offset from whence to move to
ebrus 0:6bc4ac881c8e 85 * @param whence SEEK_SET for the start of the file, SEEK_CUR for the
ebrus 0:6bc4ac881c8e 86 * current file position, or SEEK_END for the end of the file.
ebrus 0:6bc4ac881c8e 87 *
ebrus 0:6bc4ac881c8e 88 * @returns
ebrus 0:6bc4ac881c8e 89 * new file position on success,
ebrus 0:6bc4ac881c8e 90 * -1 on failure or unsupported
ebrus 0:6bc4ac881c8e 91 */
ebrus 0:6bc4ac881c8e 92 virtual off_t lseek(off_t offset, int whence) = 0;
ebrus 0:6bc4ac881c8e 93
ebrus 0:6bc4ac881c8e 94 /** Flush any buffers associated with the FileHandle, ensuring it
ebrus 0:6bc4ac881c8e 95 * is up to date on disk
ebrus 0:6bc4ac881c8e 96 *
ebrus 0:6bc4ac881c8e 97 * @returns
ebrus 0:6bc4ac881c8e 98 * 0 on success or un-needed,
ebrus 0:6bc4ac881c8e 99 * -1 on error
ebrus 0:6bc4ac881c8e 100 */
ebrus 0:6bc4ac881c8e 101 virtual int fsync() = 0;
ebrus 0:6bc4ac881c8e 102
ebrus 0:6bc4ac881c8e 103 virtual off_t flen() {
ebrus 0:6bc4ac881c8e 104 /* remember our current position */
ebrus 0:6bc4ac881c8e 105 off_t pos = lseek(0, SEEK_CUR);
ebrus 0:6bc4ac881c8e 106 if(pos == -1) return -1;
ebrus 0:6bc4ac881c8e 107 /* seek to the end to get the file length */
ebrus 0:6bc4ac881c8e 108 off_t res = lseek(0, SEEK_END);
ebrus 0:6bc4ac881c8e 109 /* return to our old position */
ebrus 0:6bc4ac881c8e 110 lseek(pos, SEEK_SET);
ebrus 0:6bc4ac881c8e 111 return res;
ebrus 0:6bc4ac881c8e 112 }
ebrus 0:6bc4ac881c8e 113
ebrus 0:6bc4ac881c8e 114 virtual ~FileHandle();
ebrus 0:6bc4ac881c8e 115 };
ebrus 0:6bc4ac881c8e 116
ebrus 0:6bc4ac881c8e 117 } // namespace mbed
ebrus 0:6bc4ac881c8e 118
ebrus 0:6bc4ac881c8e 119 #endif