Matthew Sims / mbed

Lab 1 Program C

Dependents:   Lab1C

Fork of mbed by -deleted-

FileHandle.h@11:1c1ebd0324fa, 2009-08-28 (annotated)

Committer:
rolf.meyer@arm.com
Date:
Fri Aug 28 12:10:11 2009 +0000
Revision:
11:1c1ebd0324fa
Parent:
4:5d1359a283bc
Child:
27:7110ebee3484
A shiny new version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
rolf.meyer@arm.com 11:1c1ebd0324fa 1 /* mbed Microcontroller Library - FileHandler
rolf.meyer@arm.com 11:1c1ebd0324fa 2 * Copyright (c) 2007-2009 ARM Limited. All rights reserved.
rolf.meyer@arm.com 11:1c1ebd0324fa 3 * sford
rolf.meyer@arm.com 11:1c1ebd0324fa 4 */
rolf.meyer@arm.com 11:1c1ebd0324fa 5
simon.ford@mbed.co.uk 0:82220227f4fa 6 #ifndef MBED_FILEHANDLE_H
simon.ford@mbed.co.uk 0:82220227f4fa 7 #define MBED_FILEHANDLE_H
simon.ford@mbed.co.uk 0:82220227f4fa 8
simon.ford@mbed.co.uk 4:5d1359a283bc 9 typedef int FILEHANDLE;
simon.ford@mbed.co.uk 4:5d1359a283bc 10
simon.ford@mbed.co.uk 4:5d1359a283bc 11 #include <stdio.h>
simon.ford@mbed.co.uk 4:5d1359a283bc 12 #ifdef __ARMCC_VERSION
simon.ford@mbed.co.uk 4:5d1359a283bc 13 typedef int ssize_t;
simon.ford@mbed.co.uk 4:5d1359a283bc 14 typedef long off_t;
simon.ford@mbed.co.uk 4:5d1359a283bc 15 #else
simon.ford@mbed.co.uk 4:5d1359a283bc 16 #include <sys/types.h>
simon.ford@mbed.co.uk 4:5d1359a283bc 17 #endif
simon.ford@mbed.co.uk 4:5d1359a283bc 18
simon.ford@mbed.co.uk 0:82220227f4fa 19 namespace mbed {
simon.ford@mbed.co.uk 0:82220227f4fa 20
simon.ford@mbed.co.uk 4:5d1359a283bc 21 /* Class FileHandle
simon.ford@mbed.co.uk 0:82220227f4fa 22 * An OO equivalent of the internal FILEHANDLE variable
simon.ford@mbed.co.uk 0:82220227f4fa 23 * and associated _sys_* functions
simon.ford@mbed.co.uk 0:82220227f4fa 24 *
simon.ford@mbed.co.uk 0:82220227f4fa 25 * FileHandle is an abstract class, needing at least sys_write and
simon.ford@mbed.co.uk 0:82220227f4fa 26 * sys_read to be implmented for a simple interactive device
simon.ford@mbed.co.uk 0:82220227f4fa 27 *
simon.ford@mbed.co.uk 0:82220227f4fa 28 * No one ever directly tals to/instanciates a FileHandle - it gets
simon.ford@mbed.co.uk 0:82220227f4fa 29 * created by FileSystem, and wrapped up by stdio
simon.ford@mbed.co.uk 0:82220227f4fa 30 */
simon.ford@mbed.co.uk 0:82220227f4fa 31 class FileHandle {
simon.ford@mbed.co.uk 0:82220227f4fa 32
simon.ford@mbed.co.uk 0:82220227f4fa 33 public:
simon.ford@mbed.co.uk 0:82220227f4fa 34
simon.ford@mbed.co.uk 4:5d1359a283bc 35 /* Function write
simon.ford@mbed.co.uk 4:5d1359a283bc 36 * Write the contents of a buffer to the file
simon.ford@mbed.co.uk 0:82220227f4fa 37 *
simon.ford@mbed.co.uk 4:5d1359a283bc 38 * Parameters
simon.ford@mbed.co.uk 0:82220227f4fa 39 * buffer - the buffer to write from
simon.ford@mbed.co.uk 0:82220227f4fa 40 * length - the number of characters to write
simon.ford@mbed.co.uk 0:82220227f4fa 41 *
simon.ford@mbed.co.uk 4:5d1359a283bc 42 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 43 * The number of characters written (possibly 0) on success, -1 on error.
simon.ford@mbed.co.uk 0:82220227f4fa 44 */
simon.ford@mbed.co.uk 4:5d1359a283bc 45 virtual ssize_t write(const void* buffer, size_t length) = 0;
simon.ford@mbed.co.uk 0:82220227f4fa 46
simon.ford@mbed.co.uk 4:5d1359a283bc 47 /* Function close
simon.ford@mbed.co.uk 4:5d1359a283bc 48 * Close the file
simon.ford@mbed.co.uk 4:5d1359a283bc 49 *
simon.ford@mbed.co.uk 4:5d1359a283bc 50 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 51 * Zero on success, -1 on error.
simon.ford@mbed.co.uk 4:5d1359a283bc 52 */
simon.ford@mbed.co.uk 4:5d1359a283bc 53 virtual int close() = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 54
simon.ford@mbed.co.uk 4:5d1359a283bc 55 /* Function read
simon.ford@mbed.co.uk 4:5d1359a283bc 56 * Reads the contents of the file into a buffer
simon.ford@mbed.co.uk 4:5d1359a283bc 57 *
simon.ford@mbed.co.uk 4:5d1359a283bc 58 * Parameters
simon.ford@mbed.co.uk 0:82220227f4fa 59 * buffer - the buffer to read in to
simon.ford@mbed.co.uk 0:82220227f4fa 60 * length - the number of characters to read
simon.ford@mbed.co.uk 0:82220227f4fa 61 *
simon.ford@mbed.co.uk 4:5d1359a283bc 62 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 63 * The number of characters read (zero at end of file) on success, -1 on error.
simon.ford@mbed.co.uk 4:5d1359a283bc 64 */
simon.ford@mbed.co.uk 4:5d1359a283bc 65 virtual ssize_t read(void* buffer, size_t length) = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 66
simon.ford@mbed.co.uk 4:5d1359a283bc 67 /* Function isatty
simon.ford@mbed.co.uk 4:5d1359a283bc 68 * Check if the handle is for a interactive terminal device
simon.ford@mbed.co.uk 4:5d1359a283bc 69 *
simon.ford@mbed.co.uk 4:5d1359a283bc 70 * If so, line buffered behaviour is used by default
simon.ford@mbed.co.uk 4:5d1359a283bc 71 *
simon.ford@mbed.co.uk 4:5d1359a283bc 72 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 73 * 1 if it is a terminal, 0 otherwise
simon.ford@mbed.co.uk 4:5d1359a283bc 74 */
simon.ford@mbed.co.uk 4:5d1359a283bc 75 virtual int isatty() = 0 ;
simon.ford@mbed.co.uk 0:82220227f4fa 76
simon.ford@mbed.co.uk 4:5d1359a283bc 77 /* Function lseek
simon.ford@mbed.co.uk 4:5d1359a283bc 78 * Move the file position to a given offset from a given location.
simon.ford@mbed.co.uk 4:5d1359a283bc 79 *
simon.ford@mbed.co.uk 4:5d1359a283bc 80 * Parameters
simon.ford@mbed.co.uk 4:5d1359a283bc 81 * offset - The offset from whence to move to
simon.ford@mbed.co.uk 4:5d1359a283bc 82 * whence - SEEK_SET for the start of the file, SEEK_CUR for the
simon.ford@mbed.co.uk 4:5d1359a283bc 83 * current file position, or SEEK_END for the end of the file.
simon.ford@mbed.co.uk 4:5d1359a283bc 84 *
simon.ford@mbed.co.uk 4:5d1359a283bc 85 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 86 * New file position on success, -1 on failure or unsupported
simon.ford@mbed.co.uk 4:5d1359a283bc 87 */
simon.ford@mbed.co.uk 4:5d1359a283bc 88 virtual off_t lseek(off_t offset, int whence) = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 89
simon.ford@mbed.co.uk 4:5d1359a283bc 90 /* Function fsync
simon.ford@mbed.co.uk 4:5d1359a283bc 91 * Flush any buffers associated with the FileHandle, ensuring it
simon.ford@mbed.co.uk 4:5d1359a283bc 92 * is up to date on disk
simon.ford@mbed.co.uk 4:5d1359a283bc 93 *
simon.ford@mbed.co.uk 4:5d1359a283bc 94 * Returns
simon.ford@mbed.co.uk 4:5d1359a283bc 95 * 0 on success or un-needed, -1 on error
simon.ford@mbed.co.uk 4:5d1359a283bc 96 */
simon.ford@mbed.co.uk 4:5d1359a283bc 97 virtual int fsync() = 0;
simon.ford@mbed.co.uk 4:5d1359a283bc 98
simon.ford@mbed.co.uk 4:5d1359a283bc 99 virtual off_t flen() {
simon.ford@mbed.co.uk 4:5d1359a283bc 100 /* remember our current position */
simon.ford@mbed.co.uk 4:5d1359a283bc 101 off_t pos = lseek(0, SEEK_CUR);
simon.ford@mbed.co.uk 4:5d1359a283bc 102 if(pos == -1) return -1;
simon.ford@mbed.co.uk 4:5d1359a283bc 103 /* seek to the end to get the file length */
simon.ford@mbed.co.uk 4:5d1359a283bc 104 off_t res = lseek(0, SEEK_END);
simon.ford@mbed.co.uk 4:5d1359a283bc 105 /* return to our old position */
simon.ford@mbed.co.uk 4:5d1359a283bc 106 lseek(pos, SEEK_SET);
simon.ford@mbed.co.uk 4:5d1359a283bc 107 return res;
simon.ford@mbed.co.uk 4:5d1359a283bc 108 }
simon.ford@mbed.co.uk 4:5d1359a283bc 109
simon.ford@mbed.co.uk 0:82220227f4fa 110 };
simon.ford@mbed.co.uk 0:82220227f4fa 111
simon.ford@mbed.co.uk 0:82220227f4fa 112 } // namespace mbed
simon.ford@mbed.co.uk 0:82220227f4fa 113
simon.ford@mbed.co.uk 1:6b7f447ca868 114 #endif
simon.ford@mbed.co.uk 1:6b7f447ca868 115