uspace/lib/codepage/src/cp437.c

   1 /*
   2  * Copyright (c) 2021 Jiri Svoboda
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup libcodepage
  30  * @{
  31  */
  32 /**
  33  * @file Code page 437
  34  *
  35  * The ROM fonts of graphics adapters decending from IBM's MDA/CGA
  36  * use Code Page 437 and provide popular graphic characters
  37  * (such as box drawing) used in text-based user interfaces.
  38  */
  39
  40 #include <codepage/cp437.h>
  41 #include <errno.h>
  42 #include <stdint.h>
  43 #include <str.h>
  44
  45 /** All 256 graphic characters of Code Page 437 represented in Unicode */
  46 static char32_t cp437[256] = {
  47         /* 0x */
  48         L'\x0000', L'\x263a', L'\x263b', L'\x2665',
  49         L'\x2666', L'\x2663', L'\x2660', L'\x2022',
  50         L'\x25d8', L'\x25cb', L'\x25d9', L'\x2642',
  51         L'\x2640', L'\x266a', L'\x266b', L'\x263c',
  52
  53         /* 1x */
  54         L'\x25ba', L'\x25c4', L'\x2195', L'\x203c',
  55         L'\x00b6', L'\x00a7', L'\x25ac', L'\x21a8',
  56         L'\x2191', L'\x2193', L'\x2192', L'\x2190',
  57         L'\x221f', L'\x2194', L'\x25b2', L'\x25bc',
  58
  59         /* 2x */
  60         L'\x0020', L'\x0021', L'\x0022', L'\x0023',
  61         L'\x0024', L'\x0025', L'\x0026', L'\x0027',
  62         L'\x0028', L'\x0029', L'\x002a', L'\x002b',
  63         L'\x002c', L'\x002d', L'\x002e', L'\x002f',
  64
  65         /* 3x */
  66         L'\x0030', L'\x0031', L'\x0032', L'\x0033',
  67         L'\x0034', L'\x0035', L'\x0036', L'\x0037',
  68         L'\x0038', L'\x0039', L'\x003a', L'\x003b',
  69         L'\x003c', L'\x003d', L'\x003e', L'\x003f',
  70
  71         /* 4x */
  72         L'\x0040', L'\x0041', L'\x0042', L'\x0043',
  73         L'\x0044', L'\x0045', L'\x0046', L'\x0047',
  74         L'\x0048', L'\x0049', L'\x004a', L'\x004b',
  75         L'\x004c', L'\x004d', L'\x004e', L'\x004f',
  76
  77         /* 5x */
  78         L'\x0050', L'\x0051', L'\x0052', L'\x0053',
  79         L'\x0054', L'\x0055', L'\x0056', L'\x0057',
  80         L'\x0058', L'\x0059', L'\x005a', L'\x005b',
  81         L'\x005c', L'\x005d', L'\x005e', L'\x005f',
  82
  83         /* 6x */
  84         L'\x0060', L'\x0061', L'\x0062', L'\x0063',
  85         L'\x0064', L'\x0065', L'\x0066', L'\x0067',
  86         L'\x0068', L'\x0069', L'\x006a', L'\x006b',
  87         L'\x006c', L'\x006d', L'\x006e', L'\x006f',
  88
  89         /* 7x */
  90         L'\x0070', L'\x0071', L'\x0072', L'\x0073',
  91         L'\x0074', L'\x0075', L'\x0076', L'\x0077',
  92         L'\x0078', L'\x0079', L'\x007a', L'\x007b',
  93         L'\x007c', L'\x007d', L'\x007e', L'\x2302',
  94
  95         /* 8x */
  96         L'\x00c7', L'\x00fc', L'\x00e9', L'\x00e2',
  97         L'\x00e4', L'\x00e0', L'\x00e5', L'\x00e7',
  98         L'\x00ea', L'\x00eb', L'\x00e8', L'\x00ef',
  99         L'\x00ee', L'\x00ec', L'\x00c4', L'\x00c5',
 100
 101         /* 9x */
 102         L'\x00c9', L'\x00e6', L'\x00c6', L'\x00f4',
 103         L'\x00f6', L'\x00f2', L'\x00fb', L'\x00f9',
 104         L'\x00ff', L'\x00d6', L'\x00dc', L'\x00a2',
 105         L'\x00a3', L'\x00a5', L'\x20a7', L'\x0192',
 106
 107         /* Ax */
 108         L'\x00e1', L'\x00ed', L'\x00f3', L'\x00fa',
 109         L'\x00f1', L'\x00d1', L'\x00aa', L'\x00ba',
 110         L'\x00bf', L'\x2310', L'\x00ac', L'\x00bd',
 111         L'\x00bc', L'\x00a1', L'\x00ab', L'\x00bb',
 112
 113         /* Bx */
 114         L'\x2591', L'\x2592', L'\x2593', L'\x2502',
 115         L'\x2524', L'\x2561', L'\x2562', L'\x2556',
 116         L'\x2555', L'\x2563', L'\x2551', L'\x2557',
 117         L'\x255d', L'\x255c', L'\x255b', L'\x2510',
 118
 119         /* Cx */
 120         L'\x2514', L'\x2534', L'\x252c', L'\x251c',
 121         L'\x2500', L'\x253c', L'\x255e', L'\x255f',
 122         L'\x255a', L'\x2554', L'\x2569', L'\x2566',
 123         L'\x2560', L'\x2550', L'\x256c', L'\x2567',
 124
 125         /* Dx */
 126         L'\x2568', L'\x2564', L'\x2565', L'\x2559',
 127         L'\x2558', L'\x2552', L'\x2553', L'\x256b',
 128         L'\x256a', L'\x2518', L'\x250c', L'\x2588',
 129         L'\x2584', L'\x258c', L'\x2590', L'\x2580',
 130
 131         /* Ex */
 132         L'\x03b1', L'\x00df', L'\x0393', L'\x03c0',
 133         L'\x03a3', L'\x03c3', L'\x00b5', L'\x03c4',
 134         L'\x03a6', L'\x0398', L'\x03a9', L'\x03b4',
 135         L'\x221e', L'\x03c6', L'\x03b5', L'\x2229',
 136
 137         /* Fx */
 138         L'\x2261', L'\x00b1', L'\x2265', L'\x2264',
 139         L'\x2320', L'\x2321', L'\x00f7', L'\x2248',
 140         L'\x00b0', L'\x2219', L'\x00b7', L'\x221a',
 141         L'\x207f', L'\x00b2', L'\x25a0', L'\x00a0'
 142 };
 143
 144 /** Map of Unicode characters 0x0000 - 0x0400 to code page 437 */
 145 static uint8_t u0xxx_to_cp437[0x400] = {
 146         /* 0x */
 147         [0x0000] = 0x00,
 148
 149         /* 1x */
 150         [0x00b6] = 0x14, [0x00a7] = 0x15,
 151
 152         /* 2x */
 153         [0x0020] = 0x20, [0x0021] = 0x21, [0x0022] = 0x22, [0x0023] = 0x23,
 154         [0x0024] = 0x24, [0x0025] = 0x25, [0x0026] = 0x26, [0x0027] = 0x27,
 155         [0x0028] = 0x28, [0x0029] = 0x29, [0x002a] = 0x2a, [0x002b] = 0x2b,
 156         [0x002c] = 0x2c, [0x002d] = 0x2d, [0x002e] = 0x2e, [0x002f] = 0x2f,
 157
 158         /* 3x */
 159         [0x0030] = 0x30, [0x0031] = 0x31, [0x0032] = 0x32, [0x0033] = 0x33,
 160         [0x0034] = 0x34, [0x0035] = 0x35, [0x0036] = 0x36, [0x0037] = 0x37,
 161         [0x0038] = 0x38, [0x0039] = 0x39, [0x003a] = 0x3a, [0x003b] = 0x3b,
 162         [0x003c] = 0x3c, [0x003d] = 0x3d, [0x003e] = 0x3e, [0x003f] = 0x3f,
 163
 164         /* 4x */
 165         [0x0040] = 0x40, [0x0041] = 0x41, [0x0042] = 0x42, [0x0043] = 0x43,
 166         [0x0044] = 0x44, [0x0045] = 0x45, [0x0046] = 0x46, [0x0047] = 0x47,
 167         [0x0048] = 0x48, [0x0049] = 0x49, [0x004a] = 0x4a, [0x004b] = 0x4b,
 168         [0x004c] = 0x4c, [0x004d] = 0x4d, [0x004e] = 0x4e, [0x004f] = 0x4f,
 169
 170         /* 5x */
 171         [0x0050] = 0x50, [0x0051] = 0x51, [0x0052] = 0x52, [0x0053] = 0x53,
 172         [0x0054] = 0x54, [0x0055] = 0x55, [0x0056] = 0x56, [0x0057] = 0x57,
 173         [0x0058] = 0x58, [0x0059] = 0x59, [0x005a] = 0x5a, [0x005b] = 0x5b,
 174         [0x005c] = 0x5c, [0x005d] = 0x5d, [0x005e] = 0x5e, [0x005f] = 0x5f,
 175
 176         /* 6x */
 177         [0x0060] = 0x60, [0x0061] = 0x61, [0x0062] = 0x62, [0x0063] = 0x63,
 178         [0x0064] = 0x64, [0x0065] = 0x65, [0x0066] = 0x66, [0x0067] = 0x67,
 179         [0x0068] = 0x68, [0x0069] = 0x69, [0x006a] = 0x6a, [0x006b] = 0x6b,
 180         [0x006c] = 0x6c, [0x006d] = 0x6d, [0x006e] = 0x6e, [0x006f] = 0x6f,
 181
 182         /* 7x */
 183         [0x0070] = 0x70, [0x0071] = 0x71, [0x0072] = 0x72, [0x0073] = 0x73,
 184         [0x0074] = 0x74, [0x0075] = 0x75, [0x0076] = 0x76, [0x0077] = 0x77,
 185         [0x0078] = 0x78, [0x0079] = 0x79, [0x007a] = 0x7a, [0x007b] = 0x7b,
 186         [0x007c] = 0x7c, [0x007d] = 0x7d, [0x007e] = 0x7e,
 187
 188         /* 8x */
 189         [0x00c7] = 0x80, [0x00fc] = 0x81, [0x00e9] = 0x82, [0x00e2] = 0x83,
 190         [0x00e4] = 0x84, [0x00e0] = 0x85, [0x00e5] = 0x86, [0x00e7] = 0x87,
 191         [0x00ea] = 0x88, [0x00eb] = 0x89, [0x00e8] = 0x8a, [0x00ef] = 0x8b,
 192         [0x00ee] = 0x8c, [0x00ec] = 0x8d, [0x00c4] = 0x8e, [0x00c5] = 0x8f,
 193
 194         /* 9x */
 195         [0x00c9] = 0x90, [0x00e6] = 0x91, [0x00c6] = 0x92, [0x00f4] = 0x93,
 196         [0x00f6] = 0x94, [0x00f2] = 0x95, [0x00fb] = 0x96, [0x00f9] = 0x97,
 197         [0x00ff] = 0x98, [0x00d6] = 0x99, [0x00dc] = 0x9a, [0x00a2] = 0x9b,
 198         [0x00a3] = 0x9c, [0x00a5] = 0x9d,                  [0x0192] = 0x9f,
 199
 200         /* Ax */
 201         [0x00e1] = 0xa0, [0x00ed] = 0xa1, [0x00f3] = 0xa2, [0x00fa] = 0xa3,
 202         [0x00f1] = 0xa4, [0x00d1] = 0xa5, [0x00aa] = 0xa6, [0x00ba] = 0xa7,
 203         [0x00bf] = 0xa8,                  [0x00ac] = 0xaa, [0x00bd] = 0xab,
 204         [0x00bc] = 0xac, [0x00a1] = 0xad, [0x00ab] = 0xae, [0x00bb] = 0xaf,
 205
 206         /* Ex */
 207         [0x03b1] = 0xe0, [0x00df] = 0xe1, [0x0393] = 0xe2, [0x03c0] = 0xe3,
 208         [0x03a3] = 0xe4, [0x03c3] = 0xe5, [0x00b5] = 0xe6, [0x03c4] = 0xe7,
 209         [0x03a6] = 0xe8, [0x0398] = 0xe9, [0x03a9] = 0xea, [0x03b4] = 0xeb,
 210         /* skipped */    [0x03c6] = 0xed, [0x03b5] = 0xee,
 211
 212         /* Fx */
 213         /* skipped */    [0x00b1] = 0xf1,
 214         /* skipped */                     [0x00f7] = 0xf6,
 215         [0x00b0] = 0xf8, [0x00b7] = 0xfa,
 216         /* skipped */    [0x00b2] = 0xfd,                  [0x00a0] = 0xff,
 217 };
 218
 219 /** Map of Unicode characters 0x2000 - 0x2700 to code page 437 */
 220 static uint8_t u2xxx_to_cp437[0x700] = {
 221         /* 0x */
 222         /* skipped */   [0x63a] = 0x01, [0x63b] = 0x02, [0x665] = 0x03,
 223         [0x666] = 0x04, [0x663] = 0x05, [0x660] = 0x06, [0x022] = 0x07,
 224         [0x5d8] = 0x08, [0x5cb] = 0x09, [0x5d9] = 0x0a, [0x642] = 0x0b,
 225         [0x640] = 0x0c, [0x66a] = 0x0d, [0x66b] = 0x0e, [0x63c] = 0x0f,
 226
 227         /* 1x */
 228         [0x5ba] = 0x10, [0x5c4] = 0x11, [0x195] = 0x12, [0x03c] = 0x13,
 229         /* skipped */                   [0x5ac] = 0x16, [0x1a8] = 0x17,
 230         [0x191] = 0x18, [0x193] = 0x19, [0x192] = 0x1a, [0x190] = 0x1b,
 231         [0x21f] = 0x1c, [0x194] = 0x1d, [0x5b2] = 0x1e, [0x5bc] = 0x1f,
 232
 233         /* 7x */
 234         [0x302] = 0x7f,
 235
 236         /* 9x */
 237         [0x0a7] = 0x9e,
 238
 239         /* Ax */
 240         [0x310] = 0xa9,
 241
 242         /* Bx */
 243         [0x591] = 0xb0, [0x592] = 0xb1, [0x593] = 0xb2, [0x502] = 0xb3,
 244         [0x524] = 0xb4, [0x561] = 0xb5, [0x562] = 0xb6, [0x556] = 0xb7,
 245         [0x555] = 0xb8, [0x563] = 0xb9, [0x551] = 0xba, [0x557] = 0xbb,
 246         [0x55d] = 0xbc, [0x55c] = 0xbd, [0x55b] = 0xbe, [0x510] = 0xbf,
 247
 248         /* Cx */
 249         [0x514] = 0xc0, [0x534] = 0xc1, [0x52c] = 0xc2, [0x51c] = 0xc3,
 250         [0x500] = 0xc4, [0x53c] = 0xc5, [0x55e] = 0xc6, [0x55f] = 0xc7,
 251         [0x55a] = 0xc8, [0x554] = 0xc9, [0x569] = 0xca, [0x566] = 0xcb,
 252         [0x560] = 0xcc, [0x550] = 0xcd, [0x56c] = 0xce, [0x567] = 0xcf,
 253
 254         /* Dx */
 255         [0x568] = 0xd0, [0x564] = 0xd1, [0x565] = 0xd2, [0x559] = 0xd3,
 256         [0x558] = 0xd4, [0x552] = 0xd5, [0x553] = 0xd6, [0x56b] = 0xd7,
 257         [0x56a] = 0xd8, [0x518] = 0xd9, [0x50c] = 0xda, [0x588] = 0xdb,
 258         [0x584] = 0xdc, [0x58c] = 0xdd, [0x590] = 0xde, [0x580] = 0xdf,
 259
 260         /* Ex */
 261         [0x21e] = 0xec, [0x229] = 0xef,
 262
 263         /* Fx */
 264         [0x261] = 0xf0,                 [0x265] = 0xf2, [0x264] = 0xf3,
 265         [0x320] = 0xf4, [0x321] = 0xf5,                 [0x248] = 0xf7,
 266         /* skipped */   [0x219] = 0xf9,                 [0x21a] = 0xfb,
 267         [0x07f] = 0xfc,                 [0x5a0] = 0xfe
 268 };
 269
 270 /** Decode character from code page 437 8-bit code.
 271  *
 272  * Note that this function considers all code page 437 members as graphic
 273  * characters (including those in range 0-31), not control characters.
 274  *
 275  * @param code 8-bit code
 276  * @return Character
 277  */
 278 char32_t cp437_decode(uint8_t code)
 279 {
 280         return cp437[code];
 281 }
 282
 283 /** Encode character to code page 437 8-bit code.
 284  *
 285  * Note that this function considers all code page 437 members as graphic
 286  * characters (including those in range 0-31), not control characters.
 287  *
 288  * @param c Character
 289  * @param code Place to store 8-bit code
 290  * @return EOK on success, EDOM if character cannot be encoded to CP437.
 291  */
 292 errno_t cp437_encode(char32_t c, uint8_t *code)
 293 {
 294         uint8_t b;
 295
 296         /* Unicode character 0 is the only that can map to cp437 code 0 */
 297         if (c == 0) {
 298                 *code = 0;
 299                 return EOK;
 300         }
 301
 302         b = 0;
 303
 304         /*
 305          * The map is split into two parts, 0x0000 - 0x0400 and
 306          * 0x2000 - 0x2700. This seems like a reasonable compromise
 307          * between complexity and memory efficiency.
 308          */
 309
 310         if (c < 0x400)
 311                 b = u0xxx_to_cp437[c];
 312         else if (c >= 0x2000 && c < 0x2700)
 313                 b = u2xxx_to_cp437[c - 0x2000];
 314
 315         /*
 316          * If we got zero, it was an uninitialized entry (since no Unicode
 317          * character except 0 can map to b == 0 and that was already
 318          * taken care of).
 319          */
 320         if (b == 0)
 321                 return EDOM;
 322
 323         *code = b;
 324         return EOK;
 325 }
 326
 327 /** @}
 328  */