1 /* 2 * Copyright (C) 1984-2021 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 * Routines to mess around with filenames (and files). 13 * Much of this is very OS dependent. 14 */ 15 16 #include "less.h" 17 #include "lglob.h" 18 #if MSDOS_COMPILER 19 #include <dos.h> 20 #if MSDOS_COMPILER==WIN32C && !defined(_MSC_VER) 21 #include <dir.h> 22 #endif 23 #if MSDOS_COMPILER==DJGPPC 24 #include <glob.h> 25 #include <dir.h> 26 #define _MAX_PATH PATH_MAX 27 #endif 28 #endif 29 #ifdef _OSK 30 #include <rbf.h> 31 #ifndef _OSK_MWC32 32 #include <modes.h> 33 #endif 34 #endif 35 36 #if HAVE_STAT 37 #include <sys/stat.h> 38 #ifndef S_ISDIR 39 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR) 40 #endif 41 #ifndef S_ISREG 42 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG) 43 #endif 44 #endif 45 46 extern int force_open; 47 extern int secure; 48 extern int use_lessopen; 49 extern int ctldisp; 50 extern int utf_mode; 51 extern IFILE curr_ifile; 52 extern IFILE old_ifile; 53 #if SPACES_IN_FILENAMES 54 extern char openquote; 55 extern char closequote; 56 #endif 57 58 /* 59 * Remove quotes around a filename. 60 */ 61 public char * 62 shell_unquote(str) 63 char *str; 64 { 65 char *name; 66 char *p; 67 68 name = p = (char *) ecalloc(strlen(str)+1, sizeof(char)); 69 if (*str == openquote) 70 { 71 str++; 72 while (*str != '\0') 73 { 74 if (*str == closequote) 75 { 76 if (str[1] != closequote) 77 break; 78 str++; 79 } 80 *p++ = *str++; 81 } 82 } else 83 { 84 char *esc = get_meta_escape(); 85 int esclen = (int) strlen(esc); 86 while (*str != '\0') 87 { 88 if (esclen > 0 && strncmp(str, esc, esclen) == 0) 89 str += esclen; 90 *p++ = *str++; 91 } 92 } 93 *p = '\0'; 94 return (name); 95 } 96 97 /* 98 * Get the shell's escape character. 99 */ 100 public char * 101 get_meta_escape(VOID_PARAM) 102 { 103 char *s; 104 105 s = lgetenv("LESSMETAESCAPE"); 106 if (s == NULL) 107 s = DEF_METAESCAPE; 108 return (s); 109 } 110 111 /* 112 * Get the characters which the shell considers to be "metacharacters". 113 */ 114 static char * 115 metachars(VOID_PARAM) 116 { 117 static char *mchars = NULL; 118 119 if (mchars == NULL) 120 { 121 mchars = lgetenv("LESSMETACHARS"); 122 if (mchars == NULL) 123 mchars = DEF_METACHARS; 124 } 125 return (mchars); 126 } 127 128 /* 129 * Is this a shell metacharacter? 130 */ 131 static int 132 metachar(c) 133 char c; 134 { 135 return (strchr(metachars(), c) != NULL); 136 } 137 138 /* 139 * Insert a backslash before each metacharacter in a string. 140 */ 141 public char * 142 shell_quote(s) 143 char *s; 144 { 145 char *p; 146 char *newstr; 147 int len; 148 char *esc = get_meta_escape(); 149 int esclen = (int) strlen(esc); 150 int use_quotes = 0; 151 int have_quotes = 0; 152 153 /* 154 * Determine how big a string we need to allocate. 155 */ 156 len = 1; /* Trailing null byte */ 157 for (p = s; *p != '\0'; p++) 158 { 159 len++; 160 if (*p == openquote || *p == closequote) 161 have_quotes = 1; 162 if (metachar(*p)) 163 { 164 if (esclen == 0) 165 { 166 /* 167 * We've got a metachar, but this shell 168 * doesn't support escape chars. Use quotes. 169 */ 170 use_quotes = 1; 171 } else 172 { 173 /* 174 * Allow space for the escape char. 175 */ 176 len += esclen; 177 } 178 } 179 } 180 if (use_quotes) 181 { 182 if (have_quotes) 183 /* 184 * We can't quote a string that contains quotes. 185 */ 186 return (NULL); 187 len = (int) strlen(s) + 3; 188 } 189 /* 190 * Allocate and construct the new string. 191 */ 192 newstr = p = (char *) ecalloc(len, sizeof(char)); 193 if (use_quotes) 194 { 195 SNPRINTF3(newstr, len, "%c%s%c", openquote, s, closequote); 196 } else 197 { 198 while (*s != '\0') 199 { 200 if (metachar(*s)) 201 { 202 /* 203 * Add the escape char. 204 */ 205 strcpy(p, esc); 206 p += esclen; 207 } 208 *p++ = *s++; 209 } 210 *p = '\0'; 211 } 212 return (newstr); 213 } 214 215 /* 216 * Return a pathname that points to a specified file in a specified directory. 217 * Return NULL if the file does not exist in the directory. 218 */ 219 public char * 220 dirfile(dirname, filename, must_exist) 221 char *dirname; 222 char *filename; 223 int must_exist; 224 { 225 char *pathname; 226 int len; 227 int f; 228 229 if (dirname == NULL || *dirname == '\0') 230 return (NULL); 231 /* 232 * Construct the full pathname. 233 */ 234 len = (int) (strlen(dirname) + strlen(filename) + 2); 235 pathname = (char *) calloc(len, sizeof(char)); 236 if (pathname == NULL) 237 return (NULL); 238 SNPRINTF3(pathname, len, "%s%s%s", dirname, PATHNAME_SEP, filename); 239 if (must_exist) 240 { 241 /* 242 * Make sure the file exists. 243 */ 244 f = open(pathname, OPEN_READ); 245 if (f < 0) 246 { 247 free(pathname); 248 pathname = NULL; 249 } else 250 { 251 close(f); 252 } 253 } 254 return (pathname); 255 } 256 257 /* 258 * Return the full pathname of the given file in the "home directory". 259 */ 260 public char * 261 homefile(filename) 262 char *filename; 263 { 264 char *pathname; 265 266 /* Try $HOME/filename. */ 267 pathname = dirfile(lgetenv("HOME"), filename, 1); 268 if (pathname != NULL) 269 return (pathname); 270 #if OS2 271 /* Try $INIT/filename. */ 272 pathname = dirfile(lgetenv("INIT"), filename, 1); 273 if (pathname != NULL) 274 return (pathname); 275 #endif 276 #if MSDOS_COMPILER || OS2 277 /* Look for the file anywhere on search path. */ 278 pathname = (char *) ecalloc(_MAX_PATH, sizeof(char)); 279 #if MSDOS_COMPILER==DJGPPC 280 { 281 char *res = searchpath(filename); 282 if (res == 0) 283 *pathname = '\0'; 284 else 285 strcpy(pathname, res); 286 } 287 #else 288 _searchenv(filename, "PATH", pathname); 289 #endif 290 if (*pathname != '\0') 291 return (pathname); 292 free(pathname); 293 #endif 294 return (NULL); 295 } 296 297 /* 298 * Expand a string, substituting any "%" with the current filename, 299 * and any "#" with the previous filename. 300 * But a string of N "%"s is just replaced with N-1 "%"s. 301 * Likewise for a string of N "#"s. 302 * {{ This is a lot of work just to support % and #. }} 303 */ 304 public char * 305 fexpand(s) 306 char *s; 307 { 308 char *fr, *to; 309 int n; 310 char *e; 311 IFILE ifile; 312 313 #define fchar_ifile(c) \ 314 ((c) == '%' ? curr_ifile : \ 315 (c) == '#' ? old_ifile : NULL_IFILE) 316 317 /* 318 * Make one pass to see how big a buffer we 319 * need to allocate for the expanded string. 320 */ 321 n = 0; 322 for (fr = s; *fr != '\0'; fr++) 323 { 324 switch (*fr) 325 { 326 case '%': 327 case '#': 328 if (fr > s && fr[-1] == *fr) 329 { 330 /* 331 * Second (or later) char in a string 332 * of identical chars. Treat as normal. 333 */ 334 n++; 335 } else if (fr[1] != *fr) 336 { 337 /* 338 * Single char (not repeated). Treat specially. 339 */ 340 ifile = fchar_ifile(*fr); 341 if (ifile == NULL_IFILE) 342 n++; 343 else 344 n += (int) strlen(get_filename(ifile)); 345 } 346 /* 347 * Else it is the first char in a string of 348 * identical chars. Just discard it. 349 */ 350 break; 351 default: 352 n++; 353 break; 354 } 355 } 356 357 e = (char *) ecalloc(n+1, sizeof(char)); 358 359 /* 360 * Now copy the string, expanding any "%" or "#". 361 */ 362 to = e; 363 for (fr = s; *fr != '\0'; fr++) 364 { 365 switch (*fr) 366 { 367 case '%': 368 case '#': 369 if (fr > s && fr[-1] == *fr) 370 { 371 *to++ = *fr; 372 } else if (fr[1] != *fr) 373 { 374 ifile = fchar_ifile(*fr); 375 if (ifile == NULL_IFILE) 376 *to++ = *fr; 377 else 378 { 379 strcpy(to, get_filename(ifile)); 380 to += strlen(to); 381 } 382 } 383 break; 384 default: 385 *to++ = *fr; 386 break; 387 } 388 } 389 *to = '\0'; 390 return (e); 391 } 392 393 394 #if TAB_COMPLETE_FILENAME 395 396 /* 397 * Return a blank-separated list of filenames which "complete" 398 * the given string. 399 */ 400 public char * 401 fcomplete(s) 402 char *s; 403 { 404 char *fpat; 405 char *qs; 406 407 if (secure) 408 return (NULL); 409 /* 410 * Complete the filename "s" by globbing "s*". 411 */ 412 #if MSDOS_COMPILER && (MSDOS_COMPILER == MSOFTC || MSDOS_COMPILER == BORLANDC) 413 /* 414 * But in DOS, we have to glob "s*.*". 415 * But if the final component of the filename already has 416 * a dot in it, just do "s*". 417 * (Thus, "FILE" is globbed as "FILE*.*", 418 * but "FILE.A" is globbed as "FILE.A*"). 419 */ 420 { 421 char *slash; 422 int len; 423 for (slash = s+strlen(s)-1; slash > s; slash--) 424 if (*slash == *PATHNAME_SEP || *slash == '/') 425 break; 426 len = (int) strlen(s) + 4; 427 fpat = (char *) ecalloc(len, sizeof(char)); 428 if (strchr(slash, '.') == NULL) 429 SNPRINTF1(fpat, len, "%s*.*", s); 430 else 431 SNPRINTF1(fpat, len, "%s*", s); 432 } 433 #else 434 { 435 int len = (int) strlen(s) + 2; 436 fpat = (char *) ecalloc(len, sizeof(char)); 437 SNPRINTF1(fpat, len, "%s*", s); 438 } 439 #endif 440 qs = lglob(fpat); 441 s = shell_unquote(qs); 442 if (strcmp(s,fpat) == 0) 443 { 444 /* 445 * The filename didn't expand. 446 */ 447 free(qs); 448 qs = NULL; 449 } 450 free(s); 451 free(fpat); 452 return (qs); 453 } 454 #endif 455 456 /* 457 * Try to determine if a file is "binary". 458 * This is just a guess, and we need not try too hard to make it accurate. 459 */ 460 public int 461 bin_file(f) 462 int f; 463 { 464 int n; 465 int bin_count = 0; 466 char data[256]; 467 char* p; 468 char* edata; 469 470 if (!seekable(f)) 471 return (0); 472 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 473 return (0); 474 n = read(f, data, sizeof(data)); 475 if (n <= 0) 476 return (0); 477 edata = &data[n]; 478 for (p = data; p < edata; ) 479 { 480 if (utf_mode && !is_utf8_well_formed(p, edata-data)) 481 { 482 bin_count++; 483 utf_skip_to_lead(&p, edata); 484 } else 485 { 486 LWCHAR c = step_char(&p, +1, edata); 487 struct ansi_state *pansi; 488 if (ctldisp == OPT_ONPLUS && (pansi = ansi_start(c)) != NULL) 489 { 490 skip_ansi(pansi, &p, edata); 491 ansi_done(pansi); 492 } else if (binary_char(c)) 493 bin_count++; 494 } 495 } 496 /* 497 * Call it a binary file if there are more than 5 binary characters 498 * in the first 256 bytes of the file. 499 */ 500 return (bin_count > 5); 501 } 502 503 /* 504 * Try to determine the size of a file by seeking to the end. 505 */ 506 static POSITION 507 seek_filesize(f) 508 int f; 509 { 510 off_t spos; 511 512 spos = lseek(f, (off_t)0, SEEK_END); 513 if (spos == BAD_LSEEK) 514 return (NULL_POSITION); 515 return ((POSITION) spos); 516 } 517 518 #if HAVE_POPEN 519 /* 520 * Read a string from a file. 521 * Return a pointer to the string in memory. 522 */ 523 static char * 524 readfd(fd) 525 FILE *fd; 526 { 527 int len; 528 int ch; 529 char *buf; 530 char *p; 531 532 /* 533 * Make a guess about how many chars in the string 534 * and allocate a buffer to hold it. 535 */ 536 len = 100; 537 buf = (char *) ecalloc(len, sizeof(char)); 538 for (p = buf; ; p++) 539 { 540 if ((ch = getc(fd)) == '\n' || ch == EOF) 541 break; 542 if (p - buf >= len-1) 543 { 544 /* 545 * The string is too big to fit in the buffer we have. 546 * Allocate a new buffer, twice as big. 547 */ 548 len *= 2; 549 *p = '\0'; 550 p = (char *) ecalloc(len, sizeof(char)); 551 strcpy(p, buf); 552 free(buf); 553 buf = p; 554 p = buf + strlen(buf); 555 } 556 *p = ch; 557 } 558 *p = '\0'; 559 return (buf); 560 } 561 562 /* 563 * Execute a shell command. 564 * Return a pointer to a pipe connected to the shell command's standard output. 565 */ 566 static FILE * 567 shellcmd(cmd) 568 char *cmd; 569 { 570 FILE *fd; 571 572 #if HAVE_SHELL 573 char *shell; 574 575 shell = lgetenv("SHELL"); 576 if (!isnullenv(shell)) 577 { 578 char *scmd; 579 char *esccmd; 580 581 /* 582 * Read the output of <$SHELL -c cmd>. 583 * Escape any metacharacters in the command. 584 */ 585 esccmd = shell_quote(cmd); 586 if (esccmd == NULL) 587 { 588 fd = popen(cmd, "r"); 589 } else 590 { 591 int len = (int) (strlen(shell) + strlen(esccmd) + 5); 592 scmd = (char *) ecalloc(len, sizeof(char)); 593 SNPRINTF3(scmd, len, "%s %s %s", shell, shell_coption(), esccmd); 594 free(esccmd); 595 fd = popen(scmd, "r"); 596 free(scmd); 597 } 598 } else 599 #endif 600 { 601 fd = popen(cmd, "r"); 602 } 603 /* 604 * Redirection in `popen' might have messed with the 605 * standard devices. Restore binary input mode. 606 */ 607 SET_BINARY(0); 608 return (fd); 609 } 610 611 #endif /* HAVE_POPEN */ 612 613 614 /* 615 * Expand a filename, doing any system-specific metacharacter substitutions. 616 */ 617 public char * 618 lglob(filename) 619 char *filename; 620 { 621 char *gfilename; 622 623 filename = fexpand(filename); 624 if (secure) 625 return (filename); 626 627 #ifdef DECL_GLOB_LIST 628 { 629 /* 630 * The globbing function returns a list of names. 631 */ 632 int length; 633 char *p; 634 char *qfilename; 635 DECL_GLOB_LIST(list) 636 637 GLOB_LIST(filename, list); 638 if (GLOB_LIST_FAILED(list)) 639 { 640 return (filename); 641 } 642 length = 1; /* Room for trailing null byte */ 643 for (SCAN_GLOB_LIST(list, p)) 644 { 645 INIT_GLOB_LIST(list, p); 646 qfilename = shell_quote(p); 647 if (qfilename != NULL) 648 { 649 length += strlen(qfilename) + 1; 650 free(qfilename); 651 } 652 } 653 gfilename = (char *) ecalloc(length, sizeof(char)); 654 for (SCAN_GLOB_LIST(list, p)) 655 { 656 INIT_GLOB_LIST(list, p); 657 qfilename = shell_quote(p); 658 if (qfilename != NULL) 659 { 660 sprintf(gfilename + strlen(gfilename), "%s ", qfilename); 661 free(qfilename); 662 } 663 } 664 /* 665 * Overwrite the final trailing space with a null terminator. 666 */ 667 *--p = '\0'; 668 GLOB_LIST_DONE(list); 669 } 670 #else 671 #ifdef DECL_GLOB_NAME 672 { 673 /* 674 * The globbing function returns a single name, and 675 * is called multiple times to walk thru all names. 676 */ 677 char *p; 678 int len; 679 int n; 680 char *pfilename; 681 char *qfilename; 682 DECL_GLOB_NAME(fnd,drive,dir,fname,ext,handle) 683 684 GLOB_FIRST_NAME(filename, &fnd, handle); 685 if (GLOB_FIRST_FAILED(handle)) 686 { 687 return (filename); 688 } 689 690 _splitpath(filename, drive, dir, fname, ext); 691 len = 100; 692 gfilename = (char *) ecalloc(len, sizeof(char)); 693 p = gfilename; 694 do { 695 n = (int) (strlen(drive) + strlen(dir) + strlen(fnd.GLOB_NAME) + 1); 696 pfilename = (char *) ecalloc(n, sizeof(char)); 697 SNPRINTF3(pfilename, n, "%s%s%s", drive, dir, fnd.GLOB_NAME); 698 qfilename = shell_quote(pfilename); 699 free(pfilename); 700 if (qfilename != NULL) 701 { 702 n = (int) strlen(qfilename); 703 while (p - gfilename + n + 2 >= len) 704 { 705 /* 706 * No room in current buffer. 707 * Allocate a bigger one. 708 */ 709 len *= 2; 710 *p = '\0'; 711 p = (char *) ecalloc(len, sizeof(char)); 712 strcpy(p, gfilename); 713 free(gfilename); 714 gfilename = p; 715 p = gfilename + strlen(gfilename); 716 } 717 strcpy(p, qfilename); 718 free(qfilename); 719 p += n; 720 *p++ = ' '; 721 } 722 } while (GLOB_NEXT_NAME(handle, &fnd) == 0); 723 724 /* 725 * Overwrite the final trailing space with a null terminator. 726 */ 727 *--p = '\0'; 728 GLOB_NAME_DONE(handle); 729 } 730 #else 731 #if HAVE_POPEN 732 { 733 /* 734 * We get the shell to glob the filename for us by passing 735 * an "echo" command to the shell and reading its output. 736 */ 737 FILE *fd; 738 char *s; 739 char *lessecho; 740 char *cmd; 741 char *esc; 742 int len; 743 744 esc = get_meta_escape(); 745 if (strlen(esc) == 0) 746 esc = "-"; 747 esc = shell_quote(esc); 748 if (esc == NULL) 749 { 750 return (filename); 751 } 752 lessecho = lgetenv("LESSECHO"); 753 if (isnullenv(lessecho)) 754 lessecho = "lessecho"; 755 /* 756 * Invoke lessecho, and read its output (a globbed list of filenames). 757 */ 758 len = (int) (strlen(lessecho) + strlen(filename) + (7*strlen(metachars())) + 24); 759 cmd = (char *) ecalloc(len, sizeof(char)); 760 SNPRINTF4(cmd, len, "%s -p0x%x -d0x%x -e%s ", lessecho, openquote, closequote, esc); 761 free(esc); 762 for (s = metachars(); *s != '\0'; s++) 763 sprintf(cmd + strlen(cmd), "-n0x%x ", *s); 764 sprintf(cmd + strlen(cmd), "-- %s", filename); 765 fd = shellcmd(cmd); 766 free(cmd); 767 if (fd == NULL) 768 { 769 /* 770 * Cannot create the pipe. 771 * Just return the original (fexpanded) filename. 772 */ 773 return (filename); 774 } 775 gfilename = readfd(fd); 776 pclose(fd); 777 if (*gfilename == '\0') 778 { 779 free(gfilename); 780 return (filename); 781 } 782 } 783 #else 784 /* 785 * No globbing functions at all. Just use the fexpanded filename. 786 */ 787 gfilename = save(filename); 788 #endif 789 #endif 790 #endif 791 free(filename); 792 return (gfilename); 793 } 794 795 /* 796 * Return canonical pathname. 797 */ 798 public char * 799 lrealpath(path) 800 char *path; 801 { 802 #if HAVE_REALPATH 803 char rpath[PATH_MAX]; 804 if (realpath(path, rpath) != NULL) 805 return (save(rpath)); 806 #endif 807 return (save(path)); 808 } 809 810 #if HAVE_POPEN 811 /* 812 * Return number of %s escapes in a string. 813 * Return a large number if there are any other % escapes besides %s. 814 */ 815 static int 816 num_pct_s(lessopen) 817 char *lessopen; 818 { 819 int num = 0; 820 821 while (*lessopen != '\0') 822 { 823 if (*lessopen == '%') 824 { 825 if (lessopen[1] == '%') 826 ++lessopen; 827 else if (lessopen[1] == 's') 828 ++num; 829 else 830 return (999); 831 } 832 ++lessopen; 833 } 834 return (num); 835 } 836 #endif 837 838 /* 839 * See if we should open a "replacement file" 840 * instead of the file we're about to open. 841 */ 842 public char * 843 open_altfile(filename, pf, pfd) 844 char *filename; 845 int *pf; 846 void **pfd; 847 { 848 #if !HAVE_POPEN 849 return (NULL); 850 #else 851 char *lessopen; 852 char *qfilename; 853 char *cmd; 854 int len; 855 FILE *fd; 856 #if HAVE_FILENO 857 int returnfd = 0; 858 #endif 859 860 if (!use_lessopen || secure) 861 return (NULL); 862 ch_ungetchar(-1); 863 if ((lessopen = lgetenv("LESSOPEN")) == NULL) 864 return (NULL); 865 while (*lessopen == '|') 866 { 867 /* 868 * If LESSOPEN starts with a |, it indicates 869 * a "pipe preprocessor". 870 */ 871 #if !HAVE_FILENO 872 error("LESSOPEN pipe is not supported", NULL_PARG); 873 return (NULL); 874 #else 875 lessopen++; 876 returnfd++; 877 #endif 878 } 879 if (*lessopen == '-') 880 { 881 /* 882 * Lessopen preprocessor will accept "-" as a filename. 883 */ 884 lessopen++; 885 } else 886 { 887 if (strcmp(filename, "-") == 0) 888 return (NULL); 889 } 890 if (num_pct_s(lessopen) != 1) 891 { 892 error("LESSOPEN ignored: must contain exactly one %%s", NULL_PARG); 893 return (NULL); 894 } 895 896 qfilename = shell_quote(filename); 897 len = (int) (strlen(lessopen) + strlen(qfilename) + 2); 898 cmd = (char *) ecalloc(len, sizeof(char)); 899 SNPRINTF1(cmd, len, lessopen, qfilename); 900 free(qfilename); 901 fd = shellcmd(cmd); 902 free(cmd); 903 if (fd == NULL) 904 { 905 /* 906 * Cannot create the pipe. 907 */ 908 return (NULL); 909 } 910 #if HAVE_FILENO 911 if (returnfd) 912 { 913 char c; 914 int f; 915 916 /* 917 * The alt file is a pipe. Read one char 918 * to see if the pipe will produce any data. 919 * If it does, push the char back on the pipe. 920 */ 921 f = fileno(fd); 922 SET_BINARY(f); 923 if (read(f, &c, 1) != 1) 924 { 925 /* 926 * Pipe is empty. 927 * If more than 1 pipe char was specified, 928 * the exit status tells whether the file itself 929 * is empty, or if there is no alt file. 930 * If only one pipe char, just assume no alt file. 931 */ 932 int status = pclose(fd); 933 if (returnfd > 1 && status == 0) { 934 /* File is empty. */ 935 *pfd = NULL; 936 *pf = -1; 937 return (save(FAKE_EMPTYFILE)); 938 } 939 /* No alt file. */ 940 return (NULL); 941 } 942 /* Alt pipe contains data, so use it. */ 943 ch_ungetchar(c); 944 *pfd = (void *) fd; 945 *pf = f; 946 return (save("-")); 947 } 948 #endif 949 /* The alt file is a regular file. Read its name from LESSOPEN. */ 950 cmd = readfd(fd); 951 pclose(fd); 952 if (*cmd == '\0') 953 { 954 /* 955 * Pipe is empty. This means there is no alt file. 956 */ 957 free(cmd); 958 return (NULL); 959 } 960 return (cmd); 961 #endif /* HAVE_POPEN */ 962 } 963 964 /* 965 * Close a replacement file. 966 */ 967 public void 968 close_altfile(altfilename, filename) 969 char *altfilename; 970 char *filename; 971 { 972 #if HAVE_POPEN 973 char *lessclose; 974 FILE *fd; 975 char *cmd; 976 int len; 977 978 if (secure) 979 return; 980 ch_ungetchar(-1); 981 if ((lessclose = lgetenv("LESSCLOSE")) == NULL) 982 return; 983 if (num_pct_s(lessclose) > 2) 984 { 985 error("LESSCLOSE ignored; must contain no more than 2 %%s", NULL_PARG); 986 return; 987 } 988 len = (int) (strlen(lessclose) + strlen(filename) + strlen(altfilename) + 2); 989 cmd = (char *) ecalloc(len, sizeof(char)); 990 SNPRINTF2(cmd, len, lessclose, filename, altfilename); 991 fd = shellcmd(cmd); 992 free(cmd); 993 if (fd != NULL) 994 pclose(fd); 995 #endif 996 } 997 998 /* 999 * Is the specified file a directory? 1000 */ 1001 public int 1002 is_dir(filename) 1003 char *filename; 1004 { 1005 int isdir = 0; 1006 1007 #if HAVE_STAT 1008 { 1009 int r; 1010 struct stat statbuf; 1011 1012 r = stat(filename, &statbuf); 1013 isdir = (r >= 0 && S_ISDIR(statbuf.st_mode)); 1014 } 1015 #else 1016 #ifdef _OSK 1017 { 1018 int f; 1019 1020 f = open(filename, S_IREAD | S_IFDIR); 1021 if (f >= 0) 1022 close(f); 1023 isdir = (f >= 0); 1024 } 1025 #endif 1026 #endif 1027 return (isdir); 1028 } 1029 1030 /* 1031 * Returns NULL if the file can be opened and 1032 * is an ordinary file, otherwise an error message 1033 * (if it cannot be opened or is a directory, etc.) 1034 */ 1035 public char * 1036 bad_file(filename) 1037 char *filename; 1038 { 1039 char *m = NULL; 1040 1041 if (!force_open && is_dir(filename)) 1042 { 1043 static char is_a_dir[] = " is a directory"; 1044 1045 m = (char *) ecalloc(strlen(filename) + sizeof(is_a_dir), 1046 sizeof(char)); 1047 strcpy(m, filename); 1048 strcat(m, is_a_dir); 1049 } else 1050 { 1051 #if HAVE_STAT 1052 int r; 1053 struct stat statbuf; 1054 1055 r = stat(filename, &statbuf); 1056 if (r < 0) 1057 { 1058 m = errno_message(filename); 1059 } else if (force_open) 1060 { 1061 m = NULL; 1062 } else if (!S_ISREG(statbuf.st_mode)) 1063 { 1064 static char not_reg[] = " is not a regular file (use -f to see it)"; 1065 m = (char *) ecalloc(strlen(filename) + sizeof(not_reg), 1066 sizeof(char)); 1067 strcpy(m, filename); 1068 strcat(m, not_reg); 1069 } 1070 #endif 1071 } 1072 return (m); 1073 } 1074 1075 /* 1076 * Return the size of a file, as cheaply as possible. 1077 * In Unix, we can stat the file. 1078 */ 1079 public POSITION 1080 filesize(f) 1081 int f; 1082 { 1083 #if HAVE_STAT 1084 struct stat statbuf; 1085 1086 if (fstat(f, &statbuf) >= 0) 1087 return ((POSITION) statbuf.st_size); 1088 #else 1089 #ifdef _OSK 1090 long size; 1091 1092 if ((size = (long) _gs_size(f)) >= 0) 1093 return ((POSITION) size); 1094 #endif 1095 #endif 1096 return (seek_filesize(f)); 1097 } 1098 1099 /* 1100 * 1101 */ 1102 public char * 1103 shell_coption(VOID_PARAM) 1104 { 1105 return ("-c"); 1106 } 1107 1108 /* 1109 * Return last component of a pathname. 1110 */ 1111 public char * 1112 last_component(name) 1113 char *name; 1114 { 1115 char *slash; 1116 1117 for (slash = name + strlen(name); slash > name; ) 1118 { 1119 --slash; 1120 if (*slash == *PATHNAME_SEP || *slash == '/') 1121 return (slash + 1); 1122 } 1123 return (name); 1124 } 1125