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 static char * 220 dirfile(dirname, filename) 221 char *dirname; 222 char *filename; 223 { 224 char *pathname; 225 int len; 226 int f; 227 228 if (dirname == NULL || *dirname == '\0') 229 return (NULL); 230 /* 231 * Construct the full pathname. 232 */ 233 len = (int) (strlen(dirname) + strlen(filename) + 2); 234 pathname = (char *) calloc(len, sizeof(char)); 235 if (pathname == NULL) 236 return (NULL); 237 SNPRINTF3(pathname, len, "%s%s%s", dirname, PATHNAME_SEP, filename); 238 /* 239 * Make sure the file exists. 240 */ 241 f = open(pathname, OPEN_READ); 242 if (f < 0) 243 { 244 free(pathname); 245 pathname = NULL; 246 } else 247 { 248 close(f); 249 } 250 return (pathname); 251 } 252 253 /* 254 * Return the full pathname of the given file in the "home directory". 255 */ 256 public char * 257 homefile(filename) 258 char *filename; 259 { 260 char *pathname; 261 262 /* 263 * Try $HOME/filename. 264 */ 265 pathname = dirfile(lgetenv("HOME"), filename); 266 if (pathname != NULL) 267 return (pathname); 268 #if OS2 269 /* 270 * Try $INIT/filename. 271 */ 272 pathname = dirfile(lgetenv("INIT"), filename); 273 if (pathname != NULL) 274 return (pathname); 275 #endif 276 #if MSDOS_COMPILER || OS2 277 /* 278 * Look for the file anywhere on search path. 279 */ 280 pathname = (char *) calloc(_MAX_PATH, sizeof(char)); 281 #if MSDOS_COMPILER==DJGPPC 282 { 283 char *res = searchpath(filename); 284 if (res == 0) 285 *pathname = '\0'; 286 else 287 strcpy(pathname, res); 288 } 289 #else 290 _searchenv(filename, "PATH", pathname); 291 #endif 292 if (*pathname != '\0') 293 return (pathname); 294 free(pathname); 295 #endif 296 return (NULL); 297 } 298 299 /* 300 * Expand a string, substituting any "%" with the current filename, 301 * and any "#" with the previous filename. 302 * But a string of N "%"s is just replaced with N-1 "%"s. 303 * Likewise for a string of N "#"s. 304 * {{ This is a lot of work just to support % and #. }} 305 */ 306 public char * 307 fexpand(s) 308 char *s; 309 { 310 char *fr, *to; 311 int n; 312 char *e; 313 IFILE ifile; 314 315 #define fchar_ifile(c) \ 316 ((c) == '%' ? curr_ifile : \ 317 (c) == '#' ? old_ifile : NULL_IFILE) 318 319 /* 320 * Make one pass to see how big a buffer we 321 * need to allocate for the expanded string. 322 */ 323 n = 0; 324 for (fr = s; *fr != '\0'; fr++) 325 { 326 switch (*fr) 327 { 328 case '%': 329 case '#': 330 if (fr > s && fr[-1] == *fr) 331 { 332 /* 333 * Second (or later) char in a string 334 * of identical chars. Treat as normal. 335 */ 336 n++; 337 } else if (fr[1] != *fr) 338 { 339 /* 340 * Single char (not repeated). Treat specially. 341 */ 342 ifile = fchar_ifile(*fr); 343 if (ifile == NULL_IFILE) 344 n++; 345 else 346 n += (int) strlen(get_filename(ifile)); 347 } 348 /* 349 * Else it is the first char in a string of 350 * identical chars. Just discard it. 351 */ 352 break; 353 default: 354 n++; 355 break; 356 } 357 } 358 359 e = (char *) ecalloc(n+1, sizeof(char)); 360 361 /* 362 * Now copy the string, expanding any "%" or "#". 363 */ 364 to = e; 365 for (fr = s; *fr != '\0'; fr++) 366 { 367 switch (*fr) 368 { 369 case '%': 370 case '#': 371 if (fr > s && fr[-1] == *fr) 372 { 373 *to++ = *fr; 374 } else if (fr[1] != *fr) 375 { 376 ifile = fchar_ifile(*fr); 377 if (ifile == NULL_IFILE) 378 *to++ = *fr; 379 else 380 { 381 strcpy(to, get_filename(ifile)); 382 to += strlen(to); 383 } 384 } 385 break; 386 default: 387 *to++ = *fr; 388 break; 389 } 390 } 391 *to = '\0'; 392 return (e); 393 } 394 395 396 #if TAB_COMPLETE_FILENAME 397 398 /* 399 * Return a blank-separated list of filenames which "complete" 400 * the given string. 401 */ 402 public char * 403 fcomplete(s) 404 char *s; 405 { 406 char *fpat; 407 char *qs; 408 409 if (secure) 410 return (NULL); 411 /* 412 * Complete the filename "s" by globbing "s*". 413 */ 414 #if MSDOS_COMPILER && (MSDOS_COMPILER == MSOFTC || MSDOS_COMPILER == BORLANDC) 415 /* 416 * But in DOS, we have to glob "s*.*". 417 * But if the final component of the filename already has 418 * a dot in it, just do "s*". 419 * (Thus, "FILE" is globbed as "FILE*.*", 420 * but "FILE.A" is globbed as "FILE.A*"). 421 */ 422 { 423 char *slash; 424 int len; 425 for (slash = s+strlen(s)-1; slash > s; slash--) 426 if (*slash == *PATHNAME_SEP || *slash == '/') 427 break; 428 len = (int) strlen(s) + 4; 429 fpat = (char *) ecalloc(len, sizeof(char)); 430 if (strchr(slash, '.') == NULL) 431 SNPRINTF1(fpat, len, "%s*.*", s); 432 else 433 SNPRINTF1(fpat, len, "%s*", s); 434 } 435 #else 436 { 437 int len = (int) strlen(s) + 2; 438 fpat = (char *) ecalloc(len, sizeof(char)); 439 SNPRINTF1(fpat, len, "%s*", s); 440 } 441 #endif 442 qs = lglob(fpat); 443 s = shell_unquote(qs); 444 if (strcmp(s,fpat) == 0) 445 { 446 /* 447 * The filename didn't expand. 448 */ 449 free(qs); 450 qs = NULL; 451 } 452 free(s); 453 free(fpat); 454 return (qs); 455 } 456 #endif 457 458 /* 459 * Try to determine if a file is "binary". 460 * This is just a guess, and we need not try too hard to make it accurate. 461 */ 462 public int 463 bin_file(f) 464 int f; 465 { 466 int n; 467 int bin_count = 0; 468 char data[256]; 469 char* p; 470 char* edata; 471 472 if (!seekable(f)) 473 return (0); 474 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 475 return (0); 476 n = read(f, data, sizeof(data)); 477 if (n <= 0) 478 return (0); 479 edata = &data[n]; 480 for (p = data; p < edata; ) 481 { 482 if (utf_mode && !is_utf8_well_formed(p, edata-data)) 483 { 484 bin_count++; 485 utf_skip_to_lead(&p, edata); 486 } else 487 { 488 LWCHAR c = step_char(&p, +1, edata); 489 struct ansi_state *pansi; 490 if (ctldisp == OPT_ONPLUS && (pansi = ansi_start(c)) != NULL) 491 { 492 skip_ansi(pansi, &p, edata); 493 ansi_done(pansi); 494 } else if (binary_char(c)) 495 bin_count++; 496 } 497 } 498 /* 499 * Call it a binary file if there are more than 5 binary characters 500 * in the first 256 bytes of the file. 501 */ 502 return (bin_count > 5); 503 } 504 505 /* 506 * Try to determine the size of a file by seeking to the end. 507 */ 508 static POSITION 509 seek_filesize(f) 510 int f; 511 { 512 off_t spos; 513 514 spos = lseek(f, (off_t)0, SEEK_END); 515 if (spos == BAD_LSEEK) 516 return (NULL_POSITION); 517 return ((POSITION) spos); 518 } 519 520 /* 521 * Read a string from a file. 522 * Return a pointer to the string in memory. 523 */ 524 static char * 525 readfd(fd) 526 FILE *fd; 527 { 528 int len; 529 int ch; 530 char *buf; 531 char *p; 532 533 /* 534 * Make a guess about how many chars in the string 535 * and allocate a buffer to hold it. 536 */ 537 len = 100; 538 buf = (char *) ecalloc(len, sizeof(char)); 539 for (p = buf; ; p++) 540 { 541 if ((ch = getc(fd)) == '\n' || ch == EOF) 542 break; 543 if (p - buf >= len-1) 544 { 545 /* 546 * The string is too big to fit in the buffer we have. 547 * Allocate a new buffer, twice as big. 548 */ 549 len *= 2; 550 *p = '\0'; 551 p = (char *) ecalloc(len, sizeof(char)); 552 strcpy(p, buf); 553 free(buf); 554 buf = p; 555 p = buf + strlen(buf); 556 } 557 *p = ch; 558 } 559 *p = '\0'; 560 return (buf); 561 } 562 563 564 565 #if HAVE_POPEN 566 567 /* 568 * Execute a shell command. 569 * Return a pointer to a pipe connected to the shell command's standard output. 570 */ 571 static FILE * 572 shellcmd(cmd) 573 char *cmd; 574 { 575 FILE *fd; 576 577 #if HAVE_SHELL 578 char *shell; 579 580 shell = lgetenv("SHELL"); 581 if (!isnullenv(shell)) 582 { 583 char *scmd; 584 char *esccmd; 585 586 /* 587 * Read the output of <$SHELL -c cmd>. 588 * Escape any metacharacters in the command. 589 */ 590 esccmd = shell_quote(cmd); 591 if (esccmd == NULL) 592 { 593 fd = popen(cmd, "r"); 594 } else 595 { 596 int len = (int) (strlen(shell) + strlen(esccmd) + 5); 597 scmd = (char *) ecalloc(len, sizeof(char)); 598 SNPRINTF3(scmd, len, "%s %s %s", shell, shell_coption(), esccmd); 599 free(esccmd); 600 fd = popen(scmd, "r"); 601 free(scmd); 602 } 603 } else 604 #endif 605 { 606 fd = popen(cmd, "r"); 607 } 608 /* 609 * Redirection in `popen' might have messed with the 610 * standard devices. Restore binary input mode. 611 */ 612 SET_BINARY(0); 613 return (fd); 614 } 615 616 #endif /* HAVE_POPEN */ 617 618 619 /* 620 * Expand a filename, doing any system-specific metacharacter substitutions. 621 */ 622 public char * 623 lglob(filename) 624 char *filename; 625 { 626 char *gfilename; 627 628 filename = fexpand(filename); 629 if (secure) 630 return (filename); 631 632 #ifdef DECL_GLOB_LIST 633 { 634 /* 635 * The globbing function returns a list of names. 636 */ 637 int length; 638 char *p; 639 char *qfilename; 640 DECL_GLOB_LIST(list) 641 642 GLOB_LIST(filename, list); 643 if (GLOB_LIST_FAILED(list)) 644 { 645 return (filename); 646 } 647 length = 1; /* Room for trailing null byte */ 648 for (SCAN_GLOB_LIST(list, p)) 649 { 650 INIT_GLOB_LIST(list, p); 651 qfilename = shell_quote(p); 652 if (qfilename != NULL) 653 { 654 length += strlen(qfilename) + 1; 655 free(qfilename); 656 } 657 } 658 gfilename = (char *) ecalloc(length, sizeof(char)); 659 for (SCAN_GLOB_LIST(list, p)) 660 { 661 INIT_GLOB_LIST(list, p); 662 qfilename = shell_quote(p); 663 if (qfilename != NULL) 664 { 665 sprintf(gfilename + strlen(gfilename), "%s ", qfilename); 666 free(qfilename); 667 } 668 } 669 /* 670 * Overwrite the final trailing space with a null terminator. 671 */ 672 *--p = '\0'; 673 GLOB_LIST_DONE(list); 674 } 675 #else 676 #ifdef DECL_GLOB_NAME 677 { 678 /* 679 * The globbing function returns a single name, and 680 * is called multiple times to walk thru all names. 681 */ 682 char *p; 683 int len; 684 int n; 685 char *pfilename; 686 char *qfilename; 687 DECL_GLOB_NAME(fnd,drive,dir,fname,ext,handle) 688 689 GLOB_FIRST_NAME(filename, &fnd, handle); 690 if (GLOB_FIRST_FAILED(handle)) 691 { 692 return (filename); 693 } 694 695 _splitpath(filename, drive, dir, fname, ext); 696 len = 100; 697 gfilename = (char *) ecalloc(len, sizeof(char)); 698 p = gfilename; 699 do { 700 n = (int) (strlen(drive) + strlen(dir) + strlen(fnd.GLOB_NAME) + 1); 701 pfilename = (char *) ecalloc(n, sizeof(char)); 702 SNPRINTF3(pfilename, n, "%s%s%s", drive, dir, fnd.GLOB_NAME); 703 qfilename = shell_quote(pfilename); 704 free(pfilename); 705 if (qfilename != NULL) 706 { 707 n = (int) strlen(qfilename); 708 while (p - gfilename + n + 2 >= len) 709 { 710 /* 711 * No room in current buffer. 712 * Allocate a bigger one. 713 */ 714 len *= 2; 715 *p = '\0'; 716 p = (char *) ecalloc(len, sizeof(char)); 717 strcpy(p, gfilename); 718 free(gfilename); 719 gfilename = p; 720 p = gfilename + strlen(gfilename); 721 } 722 strcpy(p, qfilename); 723 free(qfilename); 724 p += n; 725 *p++ = ' '; 726 } 727 } while (GLOB_NEXT_NAME(handle, &fnd) == 0); 728 729 /* 730 * Overwrite the final trailing space with a null terminator. 731 */ 732 *--p = '\0'; 733 GLOB_NAME_DONE(handle); 734 } 735 #else 736 #if HAVE_POPEN 737 { 738 /* 739 * We get the shell to glob the filename for us by passing 740 * an "echo" command to the shell and reading its output. 741 */ 742 FILE *fd; 743 char *s; 744 char *lessecho; 745 char *cmd; 746 char *esc; 747 int len; 748 749 esc = get_meta_escape(); 750 if (strlen(esc) == 0) 751 esc = "-"; 752 esc = shell_quote(esc); 753 if (esc == NULL) 754 { 755 return (filename); 756 } 757 lessecho = lgetenv("LESSECHO"); 758 if (isnullenv(lessecho)) 759 lessecho = "lessecho"; 760 /* 761 * Invoke lessecho, and read its output (a globbed list of filenames). 762 */ 763 len = (int) (strlen(lessecho) + strlen(filename) + (7*strlen(metachars())) + 24); 764 cmd = (char *) ecalloc(len, sizeof(char)); 765 SNPRINTF4(cmd, len, "%s -p0x%x -d0x%x -e%s ", lessecho, openquote, closequote, esc); 766 free(esc); 767 for (s = metachars(); *s != '\0'; s++) 768 sprintf(cmd + strlen(cmd), "-n0x%x ", *s); 769 sprintf(cmd + strlen(cmd), "-- %s", filename); 770 fd = shellcmd(cmd); 771 free(cmd); 772 if (fd == NULL) 773 { 774 /* 775 * Cannot create the pipe. 776 * Just return the original (fexpanded) filename. 777 */ 778 return (filename); 779 } 780 gfilename = readfd(fd); 781 pclose(fd); 782 if (*gfilename == '\0') 783 { 784 free(gfilename); 785 return (filename); 786 } 787 } 788 #else 789 /* 790 * No globbing functions at all. Just use the fexpanded filename. 791 */ 792 gfilename = save(filename); 793 #endif 794 #endif 795 #endif 796 free(filename); 797 return (gfilename); 798 } 799 800 /* 801 * Return canonical pathname. 802 */ 803 public char * 804 lrealpath(path) 805 char *path; 806 { 807 #if HAVE_REALPATH 808 char rpath[PATH_MAX]; 809 if (realpath(path, rpath) != NULL) 810 return (save(rpath)); 811 #endif 812 return (save(path)); 813 } 814 815 /* 816 * Return number of %s escapes in a string. 817 * Return a large number if there are any other % escapes besides %s. 818 */ 819 static int 820 num_pct_s(lessopen) 821 char *lessopen; 822 { 823 int num = 0; 824 825 while (*lessopen != '\0') 826 { 827 if (*lessopen == '%') 828 { 829 if (lessopen[1] == '%') 830 ++lessopen; 831 else if (lessopen[1] == 's') 832 ++num; 833 else 834 return (999); 835 } 836 ++lessopen; 837 } 838 return (num); 839 } 840 841 /* 842 * See if we should open a "replacement file" 843 * instead of the file we're about to open. 844 */ 845 public char * 846 open_altfile(filename, pf, pfd) 847 char *filename; 848 int *pf; 849 void **pfd; 850 { 851 #if !HAVE_POPEN 852 return (NULL); 853 #else 854 char *lessopen; 855 char *qfilename; 856 char *cmd; 857 int len; 858 FILE *fd; 859 #if HAVE_FILENO 860 int returnfd = 0; 861 #endif 862 863 if (!use_lessopen || secure) 864 return (NULL); 865 ch_ungetchar(-1); 866 if ((lessopen = lgetenv("LESSOPEN")) == NULL) 867 return (NULL); 868 while (*lessopen == '|') 869 { 870 /* 871 * If LESSOPEN starts with a |, it indicates 872 * a "pipe preprocessor". 873 */ 874 #if !HAVE_FILENO 875 error("LESSOPEN pipe is not supported", NULL_PARG); 876 return (NULL); 877 #else 878 lessopen++; 879 returnfd++; 880 #endif 881 } 882 if (*lessopen == '-') 883 { 884 /* 885 * Lessopen preprocessor will accept "-" as a filename. 886 */ 887 lessopen++; 888 } else 889 { 890 if (strcmp(filename, "-") == 0) 891 return (NULL); 892 } 893 if (num_pct_s(lessopen) != 1) 894 { 895 error("LESSOPEN ignored: must contain exactly one %%s", NULL_PARG); 896 return (NULL); 897 } 898 899 qfilename = shell_quote(filename); 900 len = (int) (strlen(lessopen) + strlen(qfilename) + 2); 901 cmd = (char *) ecalloc(len, sizeof(char)); 902 SNPRINTF1(cmd, len, lessopen, qfilename); 903 free(qfilename); 904 fd = shellcmd(cmd); 905 free(cmd); 906 if (fd == NULL) 907 { 908 /* 909 * Cannot create the pipe. 910 */ 911 return (NULL); 912 } 913 #if HAVE_FILENO 914 if (returnfd) 915 { 916 char c; 917 int f; 918 919 /* 920 * The alt file is a pipe. Read one char 921 * to see if the pipe will produce any data. 922 * If it does, push the char back on the pipe. 923 */ 924 f = fileno(fd); 925 SET_BINARY(f); 926 if (read(f, &c, 1) != 1) 927 { 928 /* 929 * Pipe is empty. 930 * If more than 1 pipe char was specified, 931 * the exit status tells whether the file itself 932 * is empty, or if there is no alt file. 933 * If only one pipe char, just assume no alt file. 934 */ 935 int status = pclose(fd); 936 if (returnfd > 1 && status == 0) { 937 /* File is empty. */ 938 *pfd = NULL; 939 *pf = -1; 940 return (save(FAKE_EMPTYFILE)); 941 } 942 /* No alt file. */ 943 return (NULL); 944 } 945 /* Alt pipe contains data, so use it. */ 946 ch_ungetchar(c); 947 *pfd = (void *) fd; 948 *pf = f; 949 return (save("-")); 950 } 951 #endif 952 /* The alt file is a regular file. Read its name from LESSOPEN. */ 953 cmd = readfd(fd); 954 pclose(fd); 955 if (*cmd == '\0') 956 /* 957 * Pipe is empty. This means there is no alt file. 958 */ 959 return (NULL); 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 1126