cgram.c revision 1.26
1 /* $NetBSD: cgram.c,v 1.26 2021/10/29 11:45:39 nia Exp $ */ 2 3 /*- 4 * Copyright (c) 2013, 2021 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Roland Illig. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 #if defined(__RCSID) && !defined(lint) 34 __RCSID("$NetBSD: cgram.c,v 1.26 2021/10/29 11:45:39 nia Exp $"); 35 #endif 36 37 #include <assert.h> 38 #include <ctype.h> 39 #include <curses.h> 40 #include <err.h> 41 #include <stdbool.h> 42 #include <stdio.h> 43 #include <stdlib.h> 44 #include <string.h> 45 #include <time.h> 46 47 #include "pathnames.h" 48 49 50 static bool 51 ch_isspace(char ch) 52 { 53 return isspace((unsigned char)ch) != 0; 54 } 55 56 static bool 57 ch_islower(char ch) 58 { 59 return ch >= 'a' && ch <= 'z'; 60 } 61 62 static bool 63 ch_isupper(char ch) 64 { 65 return ch >= 'A' && ch <= 'Z'; 66 } 67 68 static bool 69 ch_isalpha(char ch) 70 { 71 return ch_islower(ch) || ch_isupper(ch); 72 } 73 74 static char 75 ch_toupper(char ch) 76 { 77 return ch_islower(ch) ? (char)(ch - 'a' + 'A') : ch; 78 } 79 80 static char 81 ch_tolower(char ch) 82 { 83 return ch_isupper(ch) ? (char)(ch - 'A' + 'a') : ch; 84 } 85 86 static int 87 imax(int a, int b) 88 { 89 return a > b ? a : b; 90 } 91 92 static int 93 imin(int a, int b) 94 { 95 return a < b ? a : b; 96 } 97 98 //////////////////////////////////////////////////////////// 99 100 struct string { 101 char *s; 102 size_t len; 103 size_t cap; 104 }; 105 106 struct stringarray { 107 struct string *v; 108 size_t num; 109 }; 110 111 static void 112 string_init(struct string *s) 113 { 114 s->s = NULL; 115 s->len = 0; 116 s->cap = 0; 117 } 118 119 static void 120 string_add(struct string *s, char ch) 121 { 122 if (s->len >= s->cap) { 123 s->cap = 2 * s->cap + 16; 124 s->s = realloc(s->s, s->cap); 125 if (s->s == NULL) 126 errx(1, "Out of memory"); 127 } 128 s->s[s->len++] = ch; 129 } 130 131 static void 132 string_finish(struct string *s) 133 { 134 string_add(s, '\0'); 135 s->len--; 136 } 137 138 static void 139 stringarray_init(struct stringarray *a) 140 { 141 a->v = NULL; 142 a->num = 0; 143 } 144 145 static void 146 stringarray_done(struct stringarray *a) 147 { 148 for (size_t i = 0; i < a->num; i++) 149 free(a->v[i].s); 150 free(a->v); 151 } 152 153 static void 154 stringarray_add(struct stringarray *a, struct string *s) 155 { 156 size_t num = a->num++; 157 if (reallocarr(&a->v, a->num, sizeof(a->v[0])) != 0) 158 errx(1, "Out of memory"); 159 a->v[num] = *s; 160 } 161 162 static void 163 stringarray_dup(struct stringarray *dst, const struct stringarray *src) 164 { 165 assert(dst->num == 0); 166 for (size_t i = 0; i < src->num; i++) { 167 struct string str; 168 string_init(&str); 169 for (const char *p = src->v[i].s; *p != '\0'; p++) 170 string_add(&str, *p); 171 string_finish(&str); 172 stringarray_add(dst, &str); 173 } 174 } 175 176 //////////////////////////////////////////////////////////// 177 178 static struct stringarray lines; 179 static struct stringarray sollines; 180 static bool hinting; 181 static int extent_x; 182 static int extent_y; 183 static int offset_x; 184 static int offset_y; 185 static int cursor_x; 186 static int cursor_y; 187 188 static int 189 cur_max_x(void) 190 { 191 return (int)lines.v[cursor_y].len; 192 } 193 194 static int 195 cur_max_y(void) 196 { 197 return extent_y - 1; 198 } 199 200 static char 201 char_left_of_cursor(void) 202 { 203 if (cursor_x > 0) 204 return lines.v[cursor_y].s[cursor_x - 1]; 205 assert(cursor_y > 0); 206 return '\n'; /* eol of previous line */ 207 } 208 209 static char 210 char_at_cursor(void) 211 { 212 if (cursor_x == cur_max_x()) 213 return '\n'; 214 return lines.v[cursor_y].s[cursor_x]; 215 } 216 217 static void 218 getquote(FILE *f) 219 { 220 struct string line; 221 string_init(&line); 222 223 int ch; 224 while ((ch = fgetc(f)) != EOF) { 225 if (ch == '\n') { 226 string_finish(&line); 227 stringarray_add(&lines, &line); 228 string_init(&line); 229 } else if (ch == '\t') { 230 string_add(&line, ' '); 231 while (line.len % 8 != 0) 232 string_add(&line, ' '); 233 } else if (ch == '\b') { 234 if (line.len > 0) 235 line.len--; 236 } else { 237 string_add(&line, (char)ch); 238 } 239 } 240 241 stringarray_dup(&sollines, &lines); 242 243 extent_y = (int)lines.num; 244 for (int i = 0; i < extent_y; i++) 245 extent_x = imax(extent_x, (int)lines.v[i].len); 246 } 247 248 static void 249 readfile(const char *name) 250 { 251 FILE *f = fopen(name, "r"); 252 if (f == NULL) 253 err(1, "%s", name); 254 255 getquote(f); 256 257 if (fclose(f) != 0) 258 err(1, "%s", name); 259 } 260 261 262 static void 263 readquote(void) 264 { 265 FILE *f = popen(_PATH_FORTUNE, "r"); 266 if (f == NULL) 267 err(1, "%s", _PATH_FORTUNE); 268 269 getquote(f); 270 271 if (pclose(f) != 0) 272 exit(1); /* error message must come from child process */ 273 } 274 275 static void 276 encode(void) 277 { 278 int key[26]; 279 280 for (int i = 0; i < 26; i++) 281 key[i] = i; 282 283 for (int i = 26; i > 1; i--) { 284 int c = (int)(random() % i); 285 int t = key[i - 1]; 286 key[i - 1] = key[c]; 287 key[c] = t; 288 } 289 290 for (int y = 0; y < extent_y; y++) { 291 for (char *p = lines.v[y].s; *p != '\0'; p++) { 292 if (ch_islower(*p)) 293 *p = (char)('a' + key[*p - 'a']); 294 if (ch_isupper(*p)) 295 *p = (char)('A' + key[*p - 'A']); 296 } 297 } 298 } 299 300 static void 301 substitute(char a, char b) 302 { 303 char la = ch_tolower(a); 304 char ua = ch_toupper(a); 305 char lb = ch_tolower(b); 306 char ub = ch_toupper(b); 307 308 for (int y = 0; y < (int)lines.num; y++) { 309 for (char *p = lines.v[y].s; *p != '\0'; p++) { 310 if (*p == la) 311 *p = lb; 312 else if (*p == ua) 313 *p = ub; 314 else if (*p == lb) 315 *p = la; 316 else if (*p == ub) 317 *p = ua; 318 } 319 } 320 } 321 322 static bool 323 is_solved(void) 324 { 325 for (size_t i = 0; i < lines.num; i++) 326 if (strcmp(lines.v[i].s, sollines.v[i].s) != 0) 327 return false; 328 return true; 329 } 330 331 //////////////////////////////////////////////////////////// 332 333 static void 334 redraw(void) 335 { 336 erase(); 337 338 int max_y = imin(LINES - 1, extent_y - offset_y); 339 for (int y = 0; y < max_y; y++) { 340 move(y, 0); 341 342 int len = (int)lines.v[offset_y + y].len; 343 int max_x = imin(COLS - 1, len - offset_x); 344 const char *line = lines.v[offset_y + y].s; 345 const char *solline = sollines.v[offset_y + y].s; 346 347 for (int x = 0; x < max_x; x++) { 348 char ch = line[offset_x + x]; 349 bool bold = hinting && 350 (ch == solline[offset_x + x] || !ch_isalpha(ch)); 351 352 if (bold) 353 attron(A_BOLD); 354 addch(ch); 355 if (bold) 356 attroff(A_BOLD); 357 } 358 clrtoeol(); 359 } 360 361 move(LINES - 1, 0); 362 addstr("~ to quit, * to cheat, ^pnfb to move"); 363 364 if (is_solved()) { 365 if (extent_y + 1 - offset_y < LINES - 2) 366 move(extent_y + 1 - offset_y, 0); 367 else 368 addch(' '); 369 attron(A_BOLD | A_STANDOUT); 370 addstr("*solved*"); 371 attroff(A_BOLD | A_STANDOUT); 372 } 373 374 move(cursor_y - offset_y, cursor_x - offset_x); 375 376 refresh(); 377 } 378 379 //////////////////////////////////////////////////////////// 380 381 static void 382 saturate_cursor(void) 383 { 384 cursor_y = imax(cursor_y, 0); 385 cursor_y = imin(cursor_y, cur_max_y()); 386 387 assert(cursor_x >= 0); 388 cursor_x = imin(cursor_x, cur_max_x()); 389 } 390 391 static void 392 scroll_into_view(void) 393 { 394 if (cursor_x < offset_x) 395 offset_x = cursor_x; 396 if (cursor_x > offset_x + COLS - 1) 397 offset_x = cursor_x - (COLS - 1); 398 399 if (cursor_y < offset_y) 400 offset_y = cursor_y; 401 if (cursor_y > offset_y + LINES - 2) 402 offset_y = cursor_y - (LINES - 2); 403 } 404 405 static bool 406 can_go_left(void) 407 { 408 return cursor_y > 0 || 409 (cursor_y == 0 && cursor_x > 0); 410 } 411 412 static bool 413 can_go_right(void) 414 { 415 return cursor_y < cur_max_y() || 416 (cursor_y == cur_max_y() && cursor_x < cur_max_x()); 417 } 418 419 static void 420 go_to_prev_line(void) 421 { 422 cursor_y--; 423 cursor_x = cur_max_x(); 424 } 425 426 static void 427 go_to_next_line(void) 428 { 429 cursor_x = 0; 430 cursor_y++; 431 } 432 433 static void 434 go_left(void) 435 { 436 if (cursor_x > 0) 437 cursor_x--; 438 else if (cursor_y > 0) 439 go_to_prev_line(); 440 } 441 442 static void 443 go_right(void) 444 { 445 if (cursor_x < cur_max_x()) 446 cursor_x++; 447 else if (cursor_y < cur_max_y()) 448 go_to_next_line(); 449 } 450 451 static void 452 go_to_prev_word(void) 453 { 454 while (can_go_left() && ch_isspace(char_left_of_cursor())) 455 go_left(); 456 457 while (can_go_left() && !ch_isspace(char_left_of_cursor())) 458 go_left(); 459 } 460 461 static void 462 go_to_next_word(void) 463 { 464 while (can_go_right() && !ch_isspace(char_at_cursor())) 465 go_right(); 466 467 while (can_go_right() && ch_isspace(char_at_cursor())) 468 go_right(); 469 } 470 471 static bool 472 can_substitute_here(int ch) 473 { 474 return isascii(ch) && 475 ch_isalpha((char)ch) && 476 cursor_x < cur_max_x() && 477 ch_isalpha(char_at_cursor()); 478 } 479 480 static void 481 handle_char_input(int ch) 482 { 483 if (ch == char_at_cursor()) 484 go_right(); 485 else if (can_substitute_here(ch)) { 486 substitute(char_at_cursor(), (char)ch); 487 go_right(); 488 } else 489 beep(); 490 } 491 492 static bool 493 handle_key(void) 494 { 495 int ch = getch(); 496 497 switch (ch) { 498 case 1: /* ^A */ 499 case KEY_HOME: 500 cursor_x = 0; 501 break; 502 case 2: /* ^B */ 503 case KEY_LEFT: 504 go_left(); 505 break; 506 case 5: /* ^E */ 507 case KEY_END: 508 cursor_x = cur_max_x(); 509 break; 510 case 6: /* ^F */ 511 case KEY_RIGHT: 512 go_right(); 513 break; 514 case '\t': 515 go_to_next_word(); 516 break; 517 case KEY_BTAB: 518 go_to_prev_word(); 519 break; 520 case '\n': 521 go_to_next_line(); 522 break; 523 case 12: /* ^L */ 524 clear(); 525 break; 526 case 14: /* ^N */ 527 case KEY_DOWN: 528 cursor_y++; 529 break; 530 case 16: /* ^P */ 531 case KEY_UP: 532 cursor_y--; 533 break; 534 case KEY_PPAGE: 535 cursor_y -= LINES - 2; 536 break; 537 case KEY_NPAGE: 538 cursor_y += LINES - 2; 539 break; 540 case '*': 541 hinting = !hinting; 542 break; 543 case '~': 544 return false; 545 case KEY_RESIZE: 546 break; 547 default: 548 handle_char_input(ch); 549 break; 550 } 551 return true; 552 } 553 554 static void 555 init(const char *filename) 556 { 557 stringarray_init(&lines); 558 stringarray_init(&sollines); 559 srandom((unsigned int)time(NULL)); 560 if (filename != NULL) { 561 readfile(filename); 562 } else { 563 readquote(); 564 } 565 encode(); 566 567 initscr(); 568 cbreak(); 569 noecho(); 570 keypad(stdscr, true); 571 } 572 573 static void 574 loop(void) 575 { 576 for (;;) { 577 redraw(); 578 if (!handle_key()) 579 break; 580 saturate_cursor(); 581 scroll_into_view(); 582 } 583 } 584 585 static void 586 done(void) 587 { 588 endwin(); 589 590 stringarray_done(&sollines); 591 stringarray_done(&lines); 592 } 593 594 595 static void __dead 596 usage(void) 597 { 598 599 fprintf(stderr, "usage: %s [file]\n", getprogname()); 600 exit(1); 601 } 602 603 int 604 main(int argc, char *argv[]) 605 { 606 607 setprogname(argv[0]); 608 if (argc != 1 && argc != 2) 609 usage(); 610 611 init(argc > 1 ? argv[1] : NULL); 612 loop(); 613 done(); 614 return 0; 615 } 616
Indexes created Tue Sep 30 20:09:53 GMT 2025