Tami Farber / microbit-dal

Revised to disable BLE for radio communication as needed.

Dependencies:   BLE_API nRF51822 mbed-dev-bin

Dependents:   microbit

source/types/ManagedString.cpp@74:26717338739d, 2019-11-26 (annotated)

Committer:
tsfarber
Date:
Tue Nov 26 04:12:46 2019 +0000
Revision:
74:26717338739d
Parent:
69:b62f231e51ce 
This program combines samples programs radio TX and radio RX so that both units can send or receive depending on which unit's buttons are pressed. Tested successfully. MicroBitConfig.h has been edited to disable BLE.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
Jonathan Austin 1:8aa5cdb4ab67 1 /*
Jonathan Austin 1:8aa5cdb4ab67 2 The MIT License (MIT)
Jonathan Austin 1:8aa5cdb4ab67 3
Jonathan Austin 1:8aa5cdb4ab67 4 Copyright (c) 2016 British Broadcasting Corporation.
Jonathan Austin 1:8aa5cdb4ab67 5 This software is provided by Lancaster University by arrangement with the BBC.
Jonathan Austin 1:8aa5cdb4ab67 6
Jonathan Austin 1:8aa5cdb4ab67 7 Permission is hereby granted, free of charge, to any person obtaining a
Jonathan Austin 1:8aa5cdb4ab67 8 copy of this software and associated documentation files (the "Software"),
Jonathan Austin 1:8aa5cdb4ab67 9 to deal in the Software without restriction, including without limitation
Jonathan Austin 1:8aa5cdb4ab67 10 the rights to use, copy, modify, merge, publish, distribute, sublicense,
Jonathan Austin 1:8aa5cdb4ab67 11 and/or sell copies of the Software, and to permit persons to whom the
Jonathan Austin 1:8aa5cdb4ab67 12 Software is furnished to do so, subject to the following conditions:
Jonathan Austin 1:8aa5cdb4ab67 13
Jonathan Austin 1:8aa5cdb4ab67 14 The above copyright notice and this permission notice shall be included in
Jonathan Austin 1:8aa5cdb4ab67 15 all copies or substantial portions of the Software.
Jonathan Austin 1:8aa5cdb4ab67 16
Jonathan Austin 1:8aa5cdb4ab67 17 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
Jonathan Austin 1:8aa5cdb4ab67 18 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
Jonathan Austin 1:8aa5cdb4ab67 19 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
Jonathan Austin 1:8aa5cdb4ab67 20 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 21 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
Jonathan Austin 1:8aa5cdb4ab67 22 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
Jonathan Austin 1:8aa5cdb4ab67 23 DEALINGS IN THE SOFTWARE.
Jonathan Austin 1:8aa5cdb4ab67 24 */
Jonathan Austin 1:8aa5cdb4ab67 25
Jonathan Austin 1:8aa5cdb4ab67 26 /**
Jonathan Austin 1:8aa5cdb4ab67 27 * Class definition for a ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 28 *
Jonathan Austin 1:8aa5cdb4ab67 29 * Uses basic reference counting to implement a copy-assignable, immutable string.
Jonathan Austin 1:8aa5cdb4ab67 30 *
Jonathan Austin 1:8aa5cdb4ab67 31 * This maps closely to the constructs found in many high level application languages,
Jonathan Austin 1:8aa5cdb4ab67 32 * such as Touch Develop.
Jonathan Austin 1:8aa5cdb4ab67 33 *
Jonathan Austin 1:8aa5cdb4ab67 34 * Written from first principles here, for several reasons:
Jonathan Austin 1:8aa5cdb4ab67 35 * 1) std::shared_ptr is not yet availiable on the ARMCC compiler
Jonathan Austin 1:8aa5cdb4ab67 36 *
Jonathan Austin 1:8aa5cdb4ab67 37 * 2) to reduce memory footprint - we don't need many of the other features in the std library
Jonathan Austin 1:8aa5cdb4ab67 38 *
Jonathan Austin 1:8aa5cdb4ab67 39 * 3) it makes an interesting case study for anyone interested in seeing how it works!
Jonathan Austin 1:8aa5cdb4ab67 40 *
Jonathan Austin 1:8aa5cdb4ab67 41 * 4) we need explicit reference counting to inter-op with low-level application langauge runtimes.
Jonathan Austin 1:8aa5cdb4ab67 42 *
Jonathan Austin 1:8aa5cdb4ab67 43 * 5) the reference counting needs to also work for read-only, flash-resident strings
Jonathan Austin 1:8aa5cdb4ab67 44 */
Jonathan Austin 1:8aa5cdb4ab67 45 #include <string.h>
Jonathan Austin 1:8aa5cdb4ab67 46 #include <stdlib.h>
Jonathan Austin 1:8aa5cdb4ab67 47
Jonathan Austin 1:8aa5cdb4ab67 48 #include "mbed.h"
Jonathan Austin 1:8aa5cdb4ab67 49 #include "MicroBitConfig.h"
Jonathan Austin 1:8aa5cdb4ab67 50 #include "ManagedString.h"
Jonathan Austin 1:8aa5cdb4ab67 51 #include "MicroBitCompat.h"
Jonathan Austin 1:8aa5cdb4ab67 52
Jonathan Austin 1:8aa5cdb4ab67 53 static const char empty[] __attribute__ ((aligned (4))) = "\xff\xff\0\0\0";
Jonathan Austin 1:8aa5cdb4ab67 54
Jonathan Austin 1:8aa5cdb4ab67 55 /**
Jonathan Austin 1:8aa5cdb4ab67 56 * Internal constructor helper.
Jonathan Austin 1:8aa5cdb4ab67 57 *
Jonathan Austin 1:8aa5cdb4ab67 58 * Configures this ManagedString to refer to the static EmptyString
Jonathan Austin 1:8aa5cdb4ab67 59 */
Jonathan Austin 1:8aa5cdb4ab67 60 void ManagedString::initEmpty()
Jonathan Austin 1:8aa5cdb4ab67 61 {
Jonathan Austin 1:8aa5cdb4ab67 62 ptr = (StringData*)(void*)empty;
Jonathan Austin 1:8aa5cdb4ab67 63 }
Jonathan Austin 1:8aa5cdb4ab67 64
Jonathan Austin 1:8aa5cdb4ab67 65 /**
Jonathan Austin 1:8aa5cdb4ab67 66 * Internal constructor helper.
Jonathan Austin 1:8aa5cdb4ab67 67 *
Jonathan Austin 1:8aa5cdb4ab67 68 * Creates this ManagedString based on a given null terminated char array.
Jonathan Austin 1:8aa5cdb4ab67 69 */
Jonathan Austin 1:8aa5cdb4ab67 70 void ManagedString::initString(const char *str)
Jonathan Austin 1:8aa5cdb4ab67 71 {
Jonathan Austin 1:8aa5cdb4ab67 72 // Initialise this ManagedString as a new string, using the data provided.
Jonathan Austin 1:8aa5cdb4ab67 73 // We assume the string is sane, and null terminated.
Jonathan Austin 1:8aa5cdb4ab67 74 int len = strlen(str);
Jonathan Austin 1:8aa5cdb4ab67 75 ptr = (StringData *) malloc(4+len+1);
Jonathan Austin 1:8aa5cdb4ab67 76 ptr->init();
Jonathan Austin 1:8aa5cdb4ab67 77 ptr->len = len;
Jonathan Austin 1:8aa5cdb4ab67 78 memcpy(ptr->data, str, len+1);
Jonathan Austin 1:8aa5cdb4ab67 79 }
Jonathan Austin 1:8aa5cdb4ab67 80
Jonathan Austin 1:8aa5cdb4ab67 81 /**
Jonathan Austin 1:8aa5cdb4ab67 82 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 83 * Create a managed string from a specially prepared string literal.
Jonathan Austin 1:8aa5cdb4ab67 84 *
Jonathan Austin 1:8aa5cdb4ab67 85 * @param ptr The literal - first two bytes should be 0xff, then the length in little endian, then the literal. The literal has to be 4-byte aligned.
Jonathan Austin 1:8aa5cdb4ab67 86 *
Jonathan Austin 1:8aa5cdb4ab67 87 * @code
Jonathan Austin 1:8aa5cdb4ab67 88 * static const char hello[] __attribute__ ((aligned (4))) = "\xff\xff\x05\x00" "Hello";
Jonathan Austin 1:8aa5cdb4ab67 89 * ManagedString s((StringData*)(void*)hello);
Jonathan Austin 1:8aa5cdb4ab67 90 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 91 */
Jonathan Austin 1:8aa5cdb4ab67 92 ManagedString::ManagedString(StringData *p)
Jonathan Austin 1:8aa5cdb4ab67 93 {
Jonathan Austin 1:8aa5cdb4ab67 94 ptr = p;
Jonathan Austin 1:8aa5cdb4ab67 95 ptr->incr();
Jonathan Austin 1:8aa5cdb4ab67 96 }
Jonathan Austin 1:8aa5cdb4ab67 97
Jonathan Austin 1:8aa5cdb4ab67 98 /**
Jonathan Austin 1:8aa5cdb4ab67 99 * Get current ptr, do not decr() it, and set the current instance to empty string.
Jonathan Austin 1:8aa5cdb4ab67 100 *
Jonathan Austin 1:8aa5cdb4ab67 101 * This is to be used by specialized runtimes which pass StringData around.
Jonathan Austin 1:8aa5cdb4ab67 102 */
Jonathan Austin 1:8aa5cdb4ab67 103 StringData* ManagedString::leakData()
Jonathan Austin 1:8aa5cdb4ab67 104 {
Jonathan Austin 1:8aa5cdb4ab67 105 StringData *res = ptr;
Jonathan Austin 1:8aa5cdb4ab67 106 initEmpty();
Jonathan Austin 1:8aa5cdb4ab67 107 return res;
Jonathan Austin 1:8aa5cdb4ab67 108 }
Jonathan Austin 1:8aa5cdb4ab67 109
Jonathan Austin 1:8aa5cdb4ab67 110 /**
Jonathan Austin 1:8aa5cdb4ab67 111 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 112 *
Jonathan Austin 1:8aa5cdb4ab67 113 * Create a managed string from a given integer.
Jonathan Austin 1:8aa5cdb4ab67 114 *
Jonathan Austin 1:8aa5cdb4ab67 115 * @param value The integer from which to create the ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 116 *
Jonathan Austin 1:8aa5cdb4ab67 117 * @code
Jonathan Austin 1:8aa5cdb4ab67 118 * ManagedString s(20);
Jonathan Austin 1:8aa5cdb4ab67 119 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 120 */
Jonathan Austin 1:8aa5cdb4ab67 121 ManagedString::ManagedString(const int value)
Jonathan Austin 1:8aa5cdb4ab67 122 {
Jonathan Austin 1:8aa5cdb4ab67 123 char str[12];
Jonathan Austin 1:8aa5cdb4ab67 124
Jonathan Austin 1:8aa5cdb4ab67 125 itoa(value, str);
Jonathan Austin 1:8aa5cdb4ab67 126 initString(str);
Jonathan Austin 1:8aa5cdb4ab67 127 }
Jonathan Austin 1:8aa5cdb4ab67 128
Jonathan Austin 1:8aa5cdb4ab67 129 /**
Jonathan Austin 1:8aa5cdb4ab67 130 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 131 * Create a managed string from a given char.
Jonathan Austin 1:8aa5cdb4ab67 132 *
Jonathan Austin 1:8aa5cdb4ab67 133 * @param value The character from which to create the ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 134 *
Jonathan Austin 1:8aa5cdb4ab67 135 * @code
Jonathan Austin 1:8aa5cdb4ab67 136 * ManagedString s('a');
Jonathan Austin 1:8aa5cdb4ab67 137 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 138 */
Jonathan Austin 1:8aa5cdb4ab67 139 ManagedString::ManagedString(const char value)
Jonathan Austin 1:8aa5cdb4ab67 140 {
Jonathan Austin 1:8aa5cdb4ab67 141 char str[2] = {value, 0};
Jonathan Austin 1:8aa5cdb4ab67 142 initString(str);
Jonathan Austin 1:8aa5cdb4ab67 143 }
Jonathan Austin 1:8aa5cdb4ab67 144
Jonathan Austin 1:8aa5cdb4ab67 145
Jonathan Austin 1:8aa5cdb4ab67 146 /**
Jonathan Austin 1:8aa5cdb4ab67 147 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 148 *
Jonathan Austin 1:8aa5cdb4ab67 149 * Create a managed string from a pointer to an 8-bit character buffer.
Jonathan Austin 1:8aa5cdb4ab67 150 *
Jonathan Austin 1:8aa5cdb4ab67 151 * The buffer is copied to ensure safe memory management (the supplied
Jonathan Austin 1:8aa5cdb4ab67 152 * character buffer may be declared on the stack for instance).
Jonathan Austin 1:8aa5cdb4ab67 153 *
Jonathan Austin 1:8aa5cdb4ab67 154 * @param str The character array on which to base the new ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 155 *
Jonathan Austin 1:8aa5cdb4ab67 156 * @code
Jonathan Austin 1:8aa5cdb4ab67 157 * ManagedString s("abcdefg");
Jonathan Austin 1:8aa5cdb4ab67 158 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 159 */
Jonathan Austin 1:8aa5cdb4ab67 160 ManagedString::ManagedString(const char *str)
Jonathan Austin 1:8aa5cdb4ab67 161 {
Jonathan Austin 1:8aa5cdb4ab67 162 // Sanity check. Return EmptyString for anything distasteful
Jonathan Austin 1:8aa5cdb4ab67 163 if (str == NULL || *str == 0)
Jonathan Austin 1:8aa5cdb4ab67 164 {
Jonathan Austin 1:8aa5cdb4ab67 165 initEmpty();
Jonathan Austin 1:8aa5cdb4ab67 166 return;
Jonathan Austin 1:8aa5cdb4ab67 167 }
Jonathan Austin 1:8aa5cdb4ab67 168
Jonathan Austin 1:8aa5cdb4ab67 169 initString(str);
Jonathan Austin 1:8aa5cdb4ab67 170 }
Jonathan Austin 1:8aa5cdb4ab67 171
Jonathan Austin 1:8aa5cdb4ab67 172 /**
Jonathan Austin 1:8aa5cdb4ab67 173 * Private Constructor.
Jonathan Austin 1:8aa5cdb4ab67 174 *
Jonathan Austin 1:8aa5cdb4ab67 175 * Create a managed string based on a concat of two strings.
Jonathan Austin 1:8aa5cdb4ab67 176 * The buffer is copied to ensure sane memory management (the supplied
Jonathan Austin 1:8aa5cdb4ab67 177 * character buffer may be declared on the stack for instance).
Jonathan Austin 1:8aa5cdb4ab67 178 *
Jonathan Austin 1:8aa5cdb4ab67 179 * @param str1 The first string on which to base the new ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 180 *
Jonathan Austin 1:8aa5cdb4ab67 181 * @param str2 The second string on which to base the new ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 182 */
Jonathan Austin 1:8aa5cdb4ab67 183 ManagedString::ManagedString(const ManagedString &s1, const ManagedString &s2)
Jonathan Austin 1:8aa5cdb4ab67 184 {
Jonathan Austin 1:8aa5cdb4ab67 185 // Calculate length of new string.
Jonathan Austin 1:8aa5cdb4ab67 186 int len = s1.length() + s2.length();
Jonathan Austin 1:8aa5cdb4ab67 187
Jonathan Austin 1:8aa5cdb4ab67 188 // Create a new buffer for holding the new string data.
Jonathan Austin 1:8aa5cdb4ab67 189 ptr = (StringData*) malloc(4+len+1);
Jonathan Austin 1:8aa5cdb4ab67 190 ptr->init();
Jonathan Austin 1:8aa5cdb4ab67 191 ptr->len = len;
Jonathan Austin 1:8aa5cdb4ab67 192
Jonathan Austin 1:8aa5cdb4ab67 193 // Enter the data, and terminate the string.
Jonathan Austin 1:8aa5cdb4ab67 194 memcpy(ptr->data, s1.toCharArray(), s1.length());
Jonathan Austin 1:8aa5cdb4ab67 195 memcpy(ptr->data + s1.length(), s2.toCharArray(), s2.length());
Jonathan Austin 1:8aa5cdb4ab67 196 ptr->data[len] = 0;
Jonathan Austin 1:8aa5cdb4ab67 197 }
Jonathan Austin 1:8aa5cdb4ab67 198
Jonathan Austin 1:8aa5cdb4ab67 199
Jonathan Austin 1:8aa5cdb4ab67 200 /**
Jonathan Austin 1:8aa5cdb4ab67 201 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 202 * Create a ManagedString from a PacketBuffer. All bytes in the
Jonathan Austin 1:8aa5cdb4ab67 203 * PacketBuffer are added to the ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 204 *
Jonathan Austin 1:8aa5cdb4ab67 205 * @param buffer The PacktBuffer from which to create the ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 206 *
Jonathan Austin 1:8aa5cdb4ab67 207 * @code
Jonathan Austin 1:8aa5cdb4ab67 208 * ManagedString s = radio.datagram.recv();
Jonathan Austin 1:8aa5cdb4ab67 209 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 210 */
Jonathan Austin 1:8aa5cdb4ab67 211 ManagedString::ManagedString(PacketBuffer buffer)
Jonathan Austin 1:8aa5cdb4ab67 212 {
Jonathan Austin 1:8aa5cdb4ab67 213 // Allocate a new buffer ( just in case the data is not NULL terminated).
Jonathan Austin 1:8aa5cdb4ab67 214 ptr = (StringData*) malloc(4+buffer.length()+1);
Jonathan Austin 1:8aa5cdb4ab67 215 ptr->init();
Jonathan Austin 1:8aa5cdb4ab67 216
Jonathan Austin 1:8aa5cdb4ab67 217 // Store the length of the new string
Jonathan Austin 1:8aa5cdb4ab67 218 ptr->len = buffer.length();
Jonathan Austin 1:8aa5cdb4ab67 219 memcpy(ptr->data, buffer.getBytes(), buffer.length());
Jonathan Austin 1:8aa5cdb4ab67 220 ptr->data[buffer.length()] = 0;
Jonathan Austin 1:8aa5cdb4ab67 221 }
Jonathan Austin 1:8aa5cdb4ab67 222
Jonathan Austin 1:8aa5cdb4ab67 223 /**
Jonathan Austin 1:8aa5cdb4ab67 224 * Constructor.
Jonathan Austin 1:8aa5cdb4ab67 225 * Create a ManagedString from a pointer to an 8-bit character buffer of a given length.
Jonathan Austin 1:8aa5cdb4ab67 226 *
Jonathan Austin 1:8aa5cdb4ab67 227 * The buffer is copied to ensure sane memory management (the supplied
Jonathan Austin 1:8aa5cdb4ab67 228 * character buffer may be declared on the stack for instance).
Jonathan Austin 1:8aa5cdb4ab67 229 *
Jonathan Austin 1:8aa5cdb4ab67 230 * @param str The character array on which to base the new ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 231 *
Jonathan Austin 1:8aa5cdb4ab67 232 * @param length The length of the character array
Jonathan Austin 1:8aa5cdb4ab67 233 *
Jonathan Austin 1:8aa5cdb4ab67 234 * @code
Jonathan Austin 1:8aa5cdb4ab67 235 * ManagedString s("abcdefg",7);
Jonathan Austin 1:8aa5cdb4ab67 236 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 237 */
Jonathan Austin 1:8aa5cdb4ab67 238 ManagedString::ManagedString(const char *str, const int16_t length)
Jonathan Austin 1:8aa5cdb4ab67 239 {
Jonathan Austin 1:8aa5cdb4ab67 240 // Sanity check. Return EmptyString for anything distasteful
Jonathan Austin 1:8aa5cdb4ab67 241 if (str == NULL || *str == 0 || (uint16_t)length > strlen(str)) // XXX length should be unsigned on the interface
Jonathan Austin 1:8aa5cdb4ab67 242 {
Jonathan Austin 1:8aa5cdb4ab67 243 initEmpty();
Jonathan Austin 1:8aa5cdb4ab67 244 return;
Jonathan Austin 1:8aa5cdb4ab67 245 }
Jonathan Austin 1:8aa5cdb4ab67 246
Jonathan Austin 1:8aa5cdb4ab67 247
Jonathan Austin 1:8aa5cdb4ab67 248 // Allocate a new buffer, and create a NULL terminated string.
Jonathan Austin 1:8aa5cdb4ab67 249 ptr = (StringData*) malloc(4+length+1);
Jonathan Austin 1:8aa5cdb4ab67 250 ptr->init();
Jonathan Austin 1:8aa5cdb4ab67 251 // Store the length of the new string
Jonathan Austin 1:8aa5cdb4ab67 252 ptr->len = length;
Jonathan Austin 1:8aa5cdb4ab67 253 memcpy(ptr->data, str, length);
Jonathan Austin 1:8aa5cdb4ab67 254 ptr->data[length] = 0;
Jonathan Austin 1:8aa5cdb4ab67 255 }
Jonathan Austin 1:8aa5cdb4ab67 256
Jonathan Austin 1:8aa5cdb4ab67 257 /**
Jonathan Austin 1:8aa5cdb4ab67 258 * Copy constructor.
Jonathan Austin 1:8aa5cdb4ab67 259 * Makes a new ManagedString identical to the one supplied.
Jonathan Austin 1:8aa5cdb4ab67 260 *
Jonathan Austin 1:8aa5cdb4ab67 261 * Shares the character buffer and reference count with the supplied ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 262 *
Jonathan Austin 1:8aa5cdb4ab67 263 * @param s The ManagedString to copy.
Jonathan Austin 1:8aa5cdb4ab67 264 *
Jonathan Austin 1:8aa5cdb4ab67 265 * @code
Jonathan Austin 1:8aa5cdb4ab67 266 * ManagedString s("abcdefg");
Jonathan Austin 1:8aa5cdb4ab67 267 * ManagedString p(s);
Jonathan Austin 1:8aa5cdb4ab67 268 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 269 */
Jonathan Austin 1:8aa5cdb4ab67 270 ManagedString::ManagedString(const ManagedString &s)
Jonathan Austin 1:8aa5cdb4ab67 271 {
Jonathan Austin 1:8aa5cdb4ab67 272 ptr = s.ptr;
Jonathan Austin 1:8aa5cdb4ab67 273 ptr->incr();
Jonathan Austin 1:8aa5cdb4ab67 274 }
Jonathan Austin 1:8aa5cdb4ab67 275
Jonathan Austin 1:8aa5cdb4ab67 276
Jonathan Austin 1:8aa5cdb4ab67 277 /**
Jonathan Austin 1:8aa5cdb4ab67 278 * Default constructor.
Jonathan Austin 1:8aa5cdb4ab67 279 *
Jonathan Austin 1:8aa5cdb4ab67 280 * Create an empty ManagedString.
Jonathan Austin 1:8aa5cdb4ab67 281 *
Jonathan Austin 1:8aa5cdb4ab67 282 * @code
Jonathan Austin 1:8aa5cdb4ab67 283 * ManagedString s();
Jonathan Austin 1:8aa5cdb4ab67 284 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 285 */
Jonathan Austin 1:8aa5cdb4ab67 286 ManagedString::ManagedString()
Jonathan Austin 1:8aa5cdb4ab67 287 {
Jonathan Austin 1:8aa5cdb4ab67 288 initEmpty();
Jonathan Austin 1:8aa5cdb4ab67 289 }
Jonathan Austin 1:8aa5cdb4ab67 290
Jonathan Austin 1:8aa5cdb4ab67 291 /**
Jonathan Austin 1:8aa5cdb4ab67 292 * Destructor.
Jonathan Austin 1:8aa5cdb4ab67 293 *
Jonathan Austin 1:8aa5cdb4ab67 294 * Free this ManagedString, and decrement the reference count to the
Jonathan Austin 1:8aa5cdb4ab67 295 * internal character buffer.
Jonathan Austin 1:8aa5cdb4ab67 296 *
Jonathan Austin 1:8aa5cdb4ab67 297 * If we're holding the last reference, also free the character buffer.
Jonathan Austin 1:8aa5cdb4ab67 298 */
Jonathan Austin 1:8aa5cdb4ab67 299 ManagedString::~ManagedString()
Jonathan Austin 1:8aa5cdb4ab67 300 {
Jonathan Austin 1:8aa5cdb4ab67 301 ptr->decr();
Jonathan Austin 1:8aa5cdb4ab67 302 }
Jonathan Austin 1:8aa5cdb4ab67 303
Jonathan Austin 1:8aa5cdb4ab67 304 /**
Jonathan Austin 1:8aa5cdb4ab67 305 * Copy assign operation.
Jonathan Austin 1:8aa5cdb4ab67 306 *
Jonathan Austin 1:8aa5cdb4ab67 307 * Called when one ManagedString is assigned the value of another.
Jonathan Austin 1:8aa5cdb4ab67 308 *
LancasterUniversity 69:b62f231e51ce 309 * If the ManagedString being assigned is already referring to a character buffer,
Jonathan Austin 1:8aa5cdb4ab67 310 * decrement the reference count and free up the buffer as necessary.
Jonathan Austin 1:8aa5cdb4ab67 311 *
Jonathan Austin 1:8aa5cdb4ab67 312 * Then, update our character buffer to refer to that of the supplied ManagedString,
Jonathan Austin 1:8aa5cdb4ab67 313 * and increase its reference count.
Jonathan Austin 1:8aa5cdb4ab67 314 *
Jonathan Austin 1:8aa5cdb4ab67 315 * @param s The ManagedString to copy.
Jonathan Austin 1:8aa5cdb4ab67 316 *
Jonathan Austin 1:8aa5cdb4ab67 317 * @code
Jonathan Austin 1:8aa5cdb4ab67 318 * ManagedString s("abcd");
Jonathan Austin 1:8aa5cdb4ab67 319 * ManagedString p("efgh");
Jonathan Austin 1:8aa5cdb4ab67 320 * p = s // p now points to s, s' ref is incremented
Jonathan Austin 1:8aa5cdb4ab67 321 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 322 */
Jonathan Austin 1:8aa5cdb4ab67 323 ManagedString& ManagedString::operator = (const ManagedString& s)
Jonathan Austin 1:8aa5cdb4ab67 324 {
Jonathan Austin 1:8aa5cdb4ab67 325 if (this->ptr == s.ptr)
Jonathan Austin 1:8aa5cdb4ab67 326 return *this;
Jonathan Austin 1:8aa5cdb4ab67 327
Jonathan Austin 1:8aa5cdb4ab67 328 ptr->decr();
Jonathan Austin 1:8aa5cdb4ab67 329 ptr = s.ptr;
Jonathan Austin 1:8aa5cdb4ab67 330 ptr->incr();
Jonathan Austin 1:8aa5cdb4ab67 331
Jonathan Austin 1:8aa5cdb4ab67 332 return *this;
Jonathan Austin 1:8aa5cdb4ab67 333 }
Jonathan Austin 1:8aa5cdb4ab67 334
Jonathan Austin 1:8aa5cdb4ab67 335 /**
Jonathan Austin 1:8aa5cdb4ab67 336 * Equality operation.
Jonathan Austin 1:8aa5cdb4ab67 337 *
Jonathan Austin 1:8aa5cdb4ab67 338 * Called when one ManagedString is tested to be equal to another using the '==' operator.
Jonathan Austin 1:8aa5cdb4ab67 339 *
Jonathan Austin 1:8aa5cdb4ab67 340 * @param s The ManagedString to test ourselves against.
Jonathan Austin 1:8aa5cdb4ab67 341 *
Jonathan Austin 1:8aa5cdb4ab67 342 * @return true if this ManagedString is identical to the one supplied, false otherwise.
Jonathan Austin 1:8aa5cdb4ab67 343 *
Jonathan Austin 1:8aa5cdb4ab67 344 * @code
Jonathan Austin 1:8aa5cdb4ab67 345 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 346 * ManagedString s("abcd");
Jonathan Austin 1:8aa5cdb4ab67 347 * ManagedString p("efgh");
Jonathan Austin 1:8aa5cdb4ab67 348 *
Jonathan Austin 1:8aa5cdb4ab67 349 * if(p == s)
Jonathan Austin 1:8aa5cdb4ab67 350 * display.scroll("We are the same!");
Jonathan Austin 1:8aa5cdb4ab67 351 * else
Jonathan Austin 1:8aa5cdb4ab67 352 * display.scroll("We are different!"); //p is not equal to s - this will be called
Jonathan Austin 1:8aa5cdb4ab67 353 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 354 */
Jonathan Austin 1:8aa5cdb4ab67 355 bool ManagedString::operator== (const ManagedString& s)
Jonathan Austin 1:8aa5cdb4ab67 356 {
Jonathan Austin 1:8aa5cdb4ab67 357 return ((length() == s.length()) && (strcmp(toCharArray(),s.toCharArray())==0));
Jonathan Austin 1:8aa5cdb4ab67 358 }
Jonathan Austin 1:8aa5cdb4ab67 359
Jonathan Austin 1:8aa5cdb4ab67 360 /**
Jonathan Austin 1:8aa5cdb4ab67 361 * Inequality operation.
Jonathan Austin 1:8aa5cdb4ab67 362 *
Jonathan Austin 1:8aa5cdb4ab67 363 * Called when one ManagedString is tested to be less than another using the '<' operator.
Jonathan Austin 1:8aa5cdb4ab67 364 *
Jonathan Austin 1:8aa5cdb4ab67 365 * @param s The ManagedString to test ourselves against.
Jonathan Austin 1:8aa5cdb4ab67 366 *
Jonathan Austin 1:8aa5cdb4ab67 367 * @return true if this ManagedString is alphabetically less than to the one supplied, false otherwise.
Jonathan Austin 1:8aa5cdb4ab67 368 *
Jonathan Austin 1:8aa5cdb4ab67 369 * @code
Jonathan Austin 1:8aa5cdb4ab67 370 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 371 * ManagedString s("a");
Jonathan Austin 1:8aa5cdb4ab67 372 * ManagedString p("b");
Jonathan Austin 1:8aa5cdb4ab67 373 *
Jonathan Austin 1:8aa5cdb4ab67 374 * if(s < p)
Jonathan Austin 1:8aa5cdb4ab67 375 * display.scroll("a is before b!"); //a is before b
Jonathan Austin 1:8aa5cdb4ab67 376 * else
Jonathan Austin 1:8aa5cdb4ab67 377 * display.scroll("b is before a!");
Jonathan Austin 1:8aa5cdb4ab67 378 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 379 */
Jonathan Austin 1:8aa5cdb4ab67 380 bool ManagedString::operator< (const ManagedString& s)
Jonathan Austin 1:8aa5cdb4ab67 381 {
Jonathan Austin 1:8aa5cdb4ab67 382 return (strcmp(toCharArray(), s.toCharArray())<0);
Jonathan Austin 1:8aa5cdb4ab67 383 }
Jonathan Austin 1:8aa5cdb4ab67 384
Jonathan Austin 1:8aa5cdb4ab67 385 /**
Jonathan Austin 1:8aa5cdb4ab67 386 * Inequality operation.
Jonathan Austin 1:8aa5cdb4ab67 387 *
Jonathan Austin 1:8aa5cdb4ab67 388 * Called when one ManagedString is tested to be greater than another using the '>' operator.
Jonathan Austin 1:8aa5cdb4ab67 389 *
Jonathan Austin 1:8aa5cdb4ab67 390 * @param s The ManagedString to test ourselves against.
Jonathan Austin 1:8aa5cdb4ab67 391 *
Jonathan Austin 1:8aa5cdb4ab67 392 * @return true if this ManagedString is alphabetically greater than to the one supplied, false otherwise.
Jonathan Austin 1:8aa5cdb4ab67 393 *
Jonathan Austin 1:8aa5cdb4ab67 394 * @code
Jonathan Austin 1:8aa5cdb4ab67 395 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 396 * ManagedString s("a");
Jonathan Austin 1:8aa5cdb4ab67 397 * ManagedString p("b");
Jonathan Austin 1:8aa5cdb4ab67 398 *
Jonathan Austin 1:8aa5cdb4ab67 399 * if(p>a)
Jonathan Austin 1:8aa5cdb4ab67 400 * display.scroll("b is after a!"); //b is after a
Jonathan Austin 1:8aa5cdb4ab67 401 * else
Jonathan Austin 1:8aa5cdb4ab67 402 * display.scroll("a is after b!");
Jonathan Austin 1:8aa5cdb4ab67 403 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 404 */
Jonathan Austin 1:8aa5cdb4ab67 405 bool ManagedString::operator> (const ManagedString& s)
Jonathan Austin 1:8aa5cdb4ab67 406 {
Jonathan Austin 1:8aa5cdb4ab67 407 return (strcmp(toCharArray(), s.toCharArray())>0);
Jonathan Austin 1:8aa5cdb4ab67 408 }
Jonathan Austin 1:8aa5cdb4ab67 409
Jonathan Austin 1:8aa5cdb4ab67 410 /**
Jonathan Austin 1:8aa5cdb4ab67 411 * Extracts a ManagedString from this string, at the position provided.
Jonathan Austin 1:8aa5cdb4ab67 412 *
Jonathan Austin 1:8aa5cdb4ab67 413 * @param start The index of the first character to extract, indexed from zero.
Jonathan Austin 1:8aa5cdb4ab67 414 *
Jonathan Austin 1:8aa5cdb4ab67 415 * @param length The number of characters to extract from the start position
Jonathan Austin 1:8aa5cdb4ab67 416 *
Jonathan Austin 1:8aa5cdb4ab67 417 * @return a ManagedString representing the requested substring.
Jonathan Austin 1:8aa5cdb4ab67 418 *
Jonathan Austin 1:8aa5cdb4ab67 419 * @code
Jonathan Austin 1:8aa5cdb4ab67 420 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 421 * ManagedString s("abcdefg");
Jonathan Austin 1:8aa5cdb4ab67 422 *
Jonathan Austin 1:8aa5cdb4ab67 423 * display.scroll(s.substring(0,2)) // displays "ab"
Jonathan Austin 1:8aa5cdb4ab67 424 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 425 */
Jonathan Austin 1:8aa5cdb4ab67 426 ManagedString ManagedString::substring(int16_t start, int16_t length)
Jonathan Austin 1:8aa5cdb4ab67 427 {
Jonathan Austin 1:8aa5cdb4ab67 428 // If the parameters are illegal, just return a reference to the empty string.
Jonathan Austin 1:8aa5cdb4ab67 429 if (start >= this->length())
Jonathan Austin 1:8aa5cdb4ab67 430 return ManagedString(ManagedString::EmptyString);
Jonathan Austin 1:8aa5cdb4ab67 431
Jonathan Austin 1:8aa5cdb4ab67 432 // Compute a safe copy length;
Jonathan Austin 1:8aa5cdb4ab67 433 length = min(this->length()-start, length);
Jonathan Austin 1:8aa5cdb4ab67 434
Jonathan Austin 1:8aa5cdb4ab67 435 // Build a ManagedString from this.
Jonathan Austin 1:8aa5cdb4ab67 436 return ManagedString(toCharArray()+start, length);
Jonathan Austin 1:8aa5cdb4ab67 437 }
Jonathan Austin 1:8aa5cdb4ab67 438
Jonathan Austin 1:8aa5cdb4ab67 439 /**
LancasterUniversity 52:3db7b4d64316 440 * Concatenates two strings.
Jonathan Austin 1:8aa5cdb4ab67 441 *
LancasterUniversity 52:3db7b4d64316 442 * @param lhs The first ManagedString to concatenate.
LancasterUniversity 52:3db7b4d64316 443 * @param rhs The second ManagedString to concatenate.
Jonathan Austin 1:8aa5cdb4ab67 444 *
Jonathan Austin 1:8aa5cdb4ab67 445 * @return a new ManagedString representing the joined strings.
Jonathan Austin 1:8aa5cdb4ab67 446 *
Jonathan Austin 1:8aa5cdb4ab67 447 * @code
Jonathan Austin 1:8aa5cdb4ab67 448 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 449 * ManagedString s("abcd");
Jonathan Austin 1:8aa5cdb4ab67 450 * ManagedString p("efgh")
Jonathan Austin 1:8aa5cdb4ab67 451 *
Jonathan Austin 1:8aa5cdb4ab67 452 * display.scroll(s + p) // scrolls "abcdefgh"
Jonathan Austin 1:8aa5cdb4ab67 453 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 454 */
LancasterUniversity 52:3db7b4d64316 455 ManagedString operator+ (const ManagedString& lhs, const ManagedString& rhs)
Jonathan Austin 1:8aa5cdb4ab67 456 {
LancasterUniversity 52:3db7b4d64316 457
LancasterUniversity 52:3db7b4d64316 458 // If the either string is empty, nothing to do!
LancasterUniversity 52:3db7b4d64316 459 if (rhs.length() == 0)
LancasterUniversity 52:3db7b4d64316 460 return lhs;
Jonathan Austin 1:8aa5cdb4ab67 461
LancasterUniversity 52:3db7b4d64316 462 if (lhs.length() == 0)
LancasterUniversity 52:3db7b4d64316 463 return rhs;
Jonathan Austin 1:8aa5cdb4ab67 464
LancasterUniversity 52:3db7b4d64316 465 return ManagedString(lhs, rhs);
Jonathan Austin 1:8aa5cdb4ab67 466 }
Jonathan Austin 1:8aa5cdb4ab67 467
Jonathan Austin 1:8aa5cdb4ab67 468
Jonathan Austin 1:8aa5cdb4ab67 469 /**
Jonathan Austin 1:8aa5cdb4ab67 470 * Provides a character value at a given position in the string, indexed from zero.
Jonathan Austin 1:8aa5cdb4ab67 471 *
Jonathan Austin 1:8aa5cdb4ab67 472 * @param index The position of the character to return.
Jonathan Austin 1:8aa5cdb4ab67 473 *
LancasterUniversity 69:b62f231e51ce 474 * @return the character at position index, zero if index is invalid.
Jonathan Austin 1:8aa5cdb4ab67 475 *
Jonathan Austin 1:8aa5cdb4ab67 476 * @code
Jonathan Austin 1:8aa5cdb4ab67 477 * MicroBitDisplay display;
Jonathan Austin 1:8aa5cdb4ab67 478 * ManagedString s("abcd");
Jonathan Austin 1:8aa5cdb4ab67 479 *
Jonathan Austin 1:8aa5cdb4ab67 480 * display.scroll(s.charAt(1)) // scrolls "b"
Jonathan Austin 1:8aa5cdb4ab67 481 * @endcode
Jonathan Austin 1:8aa5cdb4ab67 482 */
Jonathan Austin 1:8aa5cdb4ab67 483 char ManagedString::charAt(int16_t index)
Jonathan Austin 1:8aa5cdb4ab67 484 {
Jonathan Austin 1:8aa5cdb4ab67 485 return (index >=0 && index < length()) ? ptr->data[index] : 0;
Jonathan Austin 1:8aa5cdb4ab67 486 }
Jonathan Austin 1:8aa5cdb4ab67 487
Jonathan Austin 1:8aa5cdb4ab67 488 /**
Jonathan Austin 1:8aa5cdb4ab67 489 * Empty string constant literal
Jonathan Austin 1:8aa5cdb4ab67 490 */
LancasterUniversity 51:9198e7bb83dc 491 ManagedString ManagedString::EmptyString((StringData*)(void*)empty);