1 /* 2 * Copyright (C) 1984-2024 Mark Nudelman 3 * 4 * You may distribute under the terms of either the GNU General Public 5 * License or the Less License, as specified in the README file. 6 * 7 * For more information, see the README file. 8 */ 9 10 11 /* 12 * Entry point, initialization, miscellaneous routines. 13 */ 14 15 #include "less.h" 16 #if MSDOS_COMPILER==WIN32C 17 #define WIN32_LEAN_AND_MEAN 18 #include <windows.h> 19 20 #if defined(MINGW) || defined(_MSC_VER) 21 #include <locale.h> 22 #include <shellapi.h> 23 #endif 24 25 public unsigned less_acp = CP_ACP; 26 #endif 27 28 public char * every_first_cmd = NULL; 29 public lbool new_file; 30 public int is_tty; 31 public IFILE curr_ifile = NULL_IFILE; 32 public IFILE old_ifile = NULL_IFILE; 33 public struct scrpos initial_scrpos; 34 public POSITION start_attnpos = NULL_POSITION; 35 public POSITION end_attnpos = NULL_POSITION; 36 public int wscroll; 37 public constant char *progname; 38 public int quitting; 39 public int dohelp; 40 static int secure_allow_features; 41 42 #if LOGFILE 43 public int logfile = -1; 44 public lbool force_logfile = FALSE; 45 public char * namelogfile = NULL; 46 #endif 47 48 #if EDITOR 49 public constant char * editor; 50 public constant char * editproto; 51 #endif 52 53 #if TAGS 54 extern char * tags; 55 extern char * tagoption; 56 extern int jump_sline; 57 #endif 58 59 #ifdef WIN32 60 static wchar_t consoleTitle[256]; 61 #endif 62 63 public int one_screen; 64 extern int less_is_more; 65 extern int missing_cap; 66 extern int know_dumb; 67 extern int quit_if_one_screen; 68 extern int no_init; 69 extern int errmsgs; 70 extern int redraw_on_quit; 71 extern int term_init_done; 72 extern int first_time; 73 74 #if MSDOS_COMPILER==WIN32C && (defined(MINGW) || defined(_MSC_VER)) 75 /* malloc'ed 0-terminated utf8 of 0-terminated wide ws, or null on errors */ 76 static char *utf8_from_wide(constant wchar_t *ws) 77 { 78 char *u8 = NULL; 79 int n = WideCharToMultiByte(CP_UTF8, 0, ws, -1, NULL, 0, NULL, NULL); 80 if (n > 0) 81 { 82 u8 = ecalloc(n, sizeof(char)); 83 WideCharToMultiByte(CP_UTF8, 0, ws, -1, u8, n, NULL, NULL); 84 } 85 return u8; 86 } 87 88 /* 89 * similar to using UTF8 manifest to make the ANSI APIs UTF8, but dynamically 90 * with setlocale. unlike the manifest, argv and environ are already ACP, so 91 * make them UTF8. Additionally, this affects only the libc/crt API, and so 92 * e.g. fopen filename becomes UTF-8, but CreateFileA filename remains CP_ACP. 93 * CP_ACP remains the original codepage - use the dynamic less_acp instead. 94 * effective on win 10 1803 or later when compiled with ucrt, else no-op. 95 */ 96 static void try_utf8_locale(int *pargc, constant char ***pargv) 97 { 98 char *locale_orig = strdup(setlocale(LC_ALL, NULL)); 99 wchar_t **wargv = NULL, *wenv, *wp; 100 constant char **u8argv; 101 char *u8e; 102 int i, n; 103 104 if (!setlocale(LC_ALL, ".UTF8")) 105 goto cleanup; /* not win10 1803+ or not ucrt */ 106 107 /* 108 * wargv is before glob expansion. some ucrt builds may expand globs 109 * before main is entered, so n may be smaller than the original argc. 110 * that's ok, because later code at main expands globs anyway. 111 */ 112 wargv = CommandLineToArgvW(GetCommandLineW(), &n); 113 if (!wargv) 114 goto bad_args; 115 116 u8argv = (constant char **) ecalloc(n + 1, sizeof(char *)); 117 for (i = 0; i < n; ++i) 118 { 119 if (!(u8argv[i] = utf8_from_wide(wargv[i]))) 120 goto bad_args; 121 } 122 u8argv[n] = 0; 123 124 less_acp = CP_UTF8; 125 *pargc = n; 126 *pargv = u8argv; /* leaked on exit */ 127 128 /* convert wide env to utf8 where we can, but don't abort on errors */ 129 if ((wenv = GetEnvironmentStringsW())) 130 { 131 for (wp = wenv; *wp; wp += wcslen(wp) + 1) 132 { 133 if ((u8e = utf8_from_wide(wp))) 134 _putenv(u8e); 135 free(u8e); /* windows putenv makes a copy */ 136 } 137 FreeEnvironmentStringsW(wenv); 138 } 139 140 goto cleanup; 141 142 bad_args: 143 error("WARNING: cannot use unicode arguments", NULL_PARG); 144 setlocale(LC_ALL, locale_orig); 145 146 cleanup: 147 free(locale_orig); 148 LocalFree(wargv); 149 } 150 #endif 151 152 static int security_feature_error(constant char *type, size_t len, constant char *name) 153 { 154 PARG parg; 155 size_t msglen = len + strlen(type) + 64; 156 char *msg = ecalloc(msglen, sizeof(char)); 157 SNPRINTF3(msg, msglen, "LESSSECURE_ALLOW: %s feature name \"%.*s\"", type, (int) len, name); 158 parg.p_string = msg; 159 error("%s", &parg); 160 free(msg); 161 return 0; 162 } 163 164 /* 165 * Return the SF_xxx value of a secure feature given the name of the feature. 166 */ 167 static int security_feature(constant char *name, size_t len) 168 { 169 struct secure_feature { constant char *name; int sf_value; }; 170 static struct secure_feature features[] = { 171 { "edit", SF_EDIT }, 172 { "examine", SF_EXAMINE }, 173 { "glob", SF_GLOB }, 174 { "history", SF_HISTORY }, 175 { "lesskey", SF_LESSKEY }, 176 { "lessopen", SF_LESSOPEN }, 177 { "logfile", SF_LOGFILE }, 178 { "osc8", SF_OSC8_OPEN }, 179 { "pipe", SF_PIPE }, 180 { "shell", SF_SHELL }, 181 { "stop", SF_STOP }, 182 { "tags", SF_TAGS }, 183 }; 184 int i; 185 int match = -1; 186 187 for (i = 0; i < countof(features); i++) 188 { 189 if (strncmp(features[i].name, name, len) == 0) 190 { 191 if (match >= 0) /* name is ambiguous */ 192 return security_feature_error("ambiguous", len, name); 193 match = i; 194 } 195 } 196 if (match < 0) 197 return security_feature_error("invalid", len, name); 198 return features[match].sf_value; 199 } 200 201 /* 202 * Set the secure_allow_features bitmask, which controls 203 * whether certain secure features are allowed. 204 */ 205 static void init_secure(void) 206 { 207 #if SECURE 208 secure_allow_features = 0; 209 #else 210 constant char *str = lgetenv("LESSSECURE"); 211 if (isnullenv(str)) 212 secure_allow_features = ~0; /* allow everything */ 213 else 214 secure_allow_features = 0; /* allow nothing */ 215 216 str = lgetenv("LESSSECURE_ALLOW"); 217 if (!isnullenv(str)) 218 { 219 for (;;) 220 { 221 constant char *estr; 222 while (*str == ' ' || *str == ',') ++str; /* skip leading spaces/commas */ 223 if (*str == '\0') break; 224 estr = strchr(str, ','); 225 if (estr == NULL) estr = str + strlen(str); 226 while (estr > str && estr[-1] == ' ') --estr; /* trim trailing spaces */ 227 secure_allow_features |= security_feature(str, ptr_diff(estr, str)); 228 str = estr; 229 } 230 } 231 #endif 232 } 233 234 /* 235 * Entry point. 236 */ 237 int main(int argc, constant char *argv[]) 238 { 239 IFILE ifile; 240 constant char *s; 241 242 #if MSDOS_COMPILER==WIN32C && (defined(MINGW) || defined(_MSC_VER)) 243 if (GetACP() != CP_UTF8) /* not using a UTF-8 manifest */ 244 try_utf8_locale(&argc, &argv); 245 #endif 246 247 #ifdef __EMX__ 248 _response(&argc, &argv); 249 _wildcard(&argc, &argv); 250 #endif 251 252 progname = *argv++; 253 argc--; 254 init_secure(); 255 256 #ifdef WIN32 257 if (getenv("HOME") == NULL) 258 { 259 /* 260 * If there is no HOME environment variable, 261 * try the concatenation of HOMEDRIVE + HOMEPATH. 262 */ 263 char *drive = getenv("HOMEDRIVE"); 264 char *path = getenv("HOMEPATH"); 265 if (drive != NULL && path != NULL) 266 { 267 char *env = (char *) ecalloc(strlen(drive) + 268 strlen(path) + 6, sizeof(char)); 269 strcpy(env, "HOME="); 270 strcat(env, drive); 271 strcat(env, path); 272 putenv(env); 273 } 274 } 275 /* on failure, consoleTitle is already a valid empty string */ 276 GetConsoleTitleW(consoleTitle, countof(consoleTitle)); 277 #endif /* WIN32 */ 278 279 /* 280 * Process command line arguments and LESS environment arguments. 281 * Command line arguments override environment arguments. 282 */ 283 is_tty = isatty(1); 284 init_mark(); 285 init_cmds(); 286 init_poll(); 287 init_charset(); 288 init_line(); 289 init_cmdhist(); 290 init_option(); 291 init_search(); 292 293 /* 294 * If the name of the executable program is "more", 295 * act like LESS_IS_MORE is set. 296 */ 297 if (strcmp(last_component(progname), "more") == 0) 298 less_is_more = 1; 299 300 init_prompt(); 301 302 init_unsupport(); 303 s = lgetenv(less_is_more ? "MORE" : "LESS"); 304 if (s != NULL) 305 scan_option(s); 306 307 #define isoptstring(s) (((s)[0] == '-' || (s)[0] == '+') && (s)[1] != '\0') 308 while (argc > 0 && (isoptstring(*argv) || isoptpending())) 309 { 310 s = *argv++; 311 argc--; 312 if (strcmp(s, "--") == 0) 313 break; 314 scan_option(s); 315 } 316 #undef isoptstring 317 318 if (isoptpending()) 319 { 320 /* 321 * Last command line option was a flag requiring a 322 * following string, but there was no following string. 323 */ 324 nopendopt(); 325 quit(QUIT_OK); 326 } 327 328 get_term(); 329 expand_cmd_tables(); 330 331 #if EDITOR 332 editor = lgetenv("VISUAL"); 333 if (editor == NULL || *editor == '\0') 334 { 335 editor = lgetenv("EDITOR"); 336 if (isnullenv(editor)) 337 editor = EDIT_PGM; 338 } 339 editproto = lgetenv("LESSEDIT"); 340 if (isnullenv(editproto)) 341 editproto = "%E ?lm+%lm. %g"; 342 #endif 343 344 /* 345 * Call get_ifile with all the command line filenames 346 * to "register" them with the ifile system. 347 */ 348 ifile = NULL_IFILE; 349 if (dohelp) 350 ifile = get_ifile(FAKE_HELPFILE, ifile); 351 while (argc-- > 0) 352 { 353 #if (MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC) 354 /* 355 * Because the "shell" doesn't expand filename patterns, 356 * treat each argument as a filename pattern rather than 357 * a single filename. 358 * Expand the pattern and iterate over the expanded list. 359 */ 360 struct textlist tlist; 361 constant char *filename; 362 char *gfilename; 363 char *qfilename; 364 365 gfilename = lglob(*argv++); 366 init_textlist(&tlist, gfilename); 367 filename = NULL; 368 while ((filename = forw_textlist(&tlist, filename)) != NULL) 369 { 370 qfilename = shell_unquote(filename); 371 (void) get_ifile(qfilename, ifile); 372 free(qfilename); 373 ifile = prev_ifile(NULL_IFILE); 374 } 375 free(gfilename); 376 #else 377 (void) get_ifile(*argv++, ifile); 378 ifile = prev_ifile(NULL_IFILE); 379 #endif 380 } 381 /* 382 * Set up terminal, etc. 383 */ 384 if (!is_tty) 385 { 386 /* 387 * Output is not a tty. 388 * Just copy the input file(s) to output. 389 */ 390 set_output(1); /* write to stdout */ 391 SET_BINARY(1); 392 if (edit_first() == 0) 393 { 394 do { 395 cat_file(); 396 } while (edit_next(1) == 0); 397 } 398 quit(QUIT_OK); 399 } 400 401 if (missing_cap && !know_dumb) 402 error("WARNING: terminal is not fully functional", NULL_PARG); 403 open_getchr(); 404 raw_mode(1); 405 init_signals(1); 406 407 /* 408 * Select the first file to examine. 409 */ 410 #if TAGS 411 if (tagoption != NULL || strcmp(tags, "-") == 0) 412 { 413 /* 414 * A -t option was given. 415 * Verify that no filenames were also given. 416 * Edit the file selected by the "tags" search, 417 * and search for the proper line in the file. 418 */ 419 if (nifile() > 0) 420 { 421 error("No filenames allowed with -t option", NULL_PARG); 422 quit(QUIT_ERROR); 423 } 424 findtag(tagoption); 425 if (edit_tagfile()) /* Edit file which contains the tag */ 426 quit(QUIT_ERROR); 427 /* 428 * Search for the line which contains the tag. 429 * Set up initial_scrpos so we display that line. 430 */ 431 initial_scrpos.pos = tagsearch(); 432 if (initial_scrpos.pos == NULL_POSITION) 433 quit(QUIT_ERROR); 434 initial_scrpos.ln = jump_sline; 435 } else 436 #endif 437 { 438 if (edit_first()) 439 quit(QUIT_ERROR); 440 /* 441 * See if file fits on one screen to decide whether 442 * to send terminal init. But don't need this 443 * if -X (no_init) overrides this (see init()). 444 */ 445 if (quit_if_one_screen) 446 { 447 if (nifile() > 1) /* If more than one file, -F cannot be used */ 448 quit_if_one_screen = FALSE; 449 else if (!no_init) 450 one_screen = get_one_screen(); 451 } 452 } 453 454 if (errmsgs > 0) 455 { 456 /* 457 * We displayed some messages on error output 458 * (file descriptor 2; see flush()). 459 * Before erasing the screen contents, wait for a keystroke. 460 */ 461 less_printf("Press RETURN to continue ", NULL_PARG); 462 get_return(); 463 putchr('\n'); 464 } 465 set_output(1); 466 init(); 467 commands(); 468 quit(QUIT_OK); 469 /*NOTREACHED*/ 470 return (0); 471 } 472 473 /* 474 * Copy a string to a "safe" place 475 * (that is, to a buffer allocated by calloc). 476 */ 477 public char * saven(constant char *s, size_t n) 478 { 479 char *p = (char *) ecalloc(n+1, sizeof(char)); 480 strncpy(p, s, n); 481 p[n] = '\0'; 482 return (p); 483 } 484 485 public char * save(constant char *s) 486 { 487 return saven(s, strlen(s)); 488 } 489 490 public void out_of_memory(void) 491 { 492 error("Cannot allocate memory", NULL_PARG); 493 quit(QUIT_ERROR); 494 } 495 496 /* 497 * Allocate memory. 498 * Like calloc(), but never returns an error (NULL). 499 */ 500 public void * ecalloc(size_t count, size_t size) 501 { 502 void * p; 503 504 p = (void *) calloc(count, size); 505 if (p == NULL) 506 out_of_memory(); 507 return p; 508 } 509 510 /* 511 * Skip leading spaces in a string. 512 */ 513 public char * skipsp(char *s) 514 { 515 while (*s == ' ' || *s == '\t') 516 s++; 517 return (s); 518 } 519 520 /* {{ There must be a better way. }} */ 521 public constant char * skipspc(constant char *s) 522 { 523 while (*s == ' ' || *s == '\t') 524 s++; 525 return (s); 526 } 527 528 /* 529 * See how many characters of two strings are identical. 530 * If uppercase is true, the first string must begin with an uppercase 531 * character; the remainder of the first string may be either case. 532 */ 533 public size_t sprefix(constant char *ps, constant char *s, int uppercase) 534 { 535 char c; 536 char sc; 537 size_t len = 0; 538 539 for ( ; *s != '\0'; s++, ps++) 540 { 541 c = *ps; 542 if (uppercase) 543 { 544 if (len == 0 && ASCII_IS_LOWER(c)) 545 return (0); 546 if (ASCII_IS_UPPER(c)) 547 c = ASCII_TO_LOWER(c); 548 } 549 sc = *s; 550 if (len > 0 && ASCII_IS_UPPER(sc)) 551 sc = ASCII_TO_LOWER(sc); 552 if (c != sc) 553 break; 554 len++; 555 } 556 return (len); 557 } 558 559 /* 560 * Exit the program. 561 */ 562 public void quit(int status) 563 { 564 static int save_status; 565 566 /* 567 * Put cursor at bottom left corner, clear the line, 568 * reset the terminal modes, and exit. 569 */ 570 if (status < 0) 571 status = save_status; 572 else 573 save_status = status; 574 quitting = 1; 575 check_altpipe_error(); 576 if (interactive()) 577 clear_bot(); 578 deinit(); 579 flush(); 580 if (redraw_on_quit && term_init_done) 581 { 582 /* 583 * The last file text displayed might have been on an 584 * alternate screen, which now (since deinit) cannot be seen. 585 * redraw_on_quit tells us to redraw it on the main screen. 586 */ 587 first_time = 1; /* Don't print "skipping" or tildes */ 588 repaint(); 589 flush(); 590 } 591 edit((char*)NULL); 592 save_cmdhist(); 593 raw_mode(0); 594 #if MSDOS_COMPILER && MSDOS_COMPILER != DJGPPC 595 /* 596 * If we don't close 2, we get some garbage from 597 * 2's buffer when it flushes automatically. 598 * I cannot track this one down RB 599 * The same bug shows up if we use ^C^C to abort. 600 */ 601 close(2); 602 #endif 603 #ifdef WIN32 604 SetConsoleTitleW(consoleTitle); 605 #endif 606 close_getchr(); 607 exit(status); 608 } 609 610 /* 611 * Are all the features in the features mask allowed by security? 612 */ 613 public int secure_allow(int features) 614 { 615 return ((secure_allow_features & features) == features); 616 } 617