1 /* 2 * Copyright (C) 1984-2007 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 about less, or for information on how to 8 * contact the author, see the README file. 9 */ 10 11 12 /* 13 * Routines to mess around with filenames (and files). 14 * Much of this is very OS dependent. 15 */ 16 17 #include "less.h" 18 #include "lglob.h" 19 #if MSDOS_COMPILER 20 #include <dos.h> 21 #if MSDOS_COMPILER==WIN32C && !defined(_MSC_VER) 22 #include <dir.h> 23 #endif 24 #if MSDOS_COMPILER==DJGPPC 25 #include <glob.h> 26 #include <dir.h> 27 #define _MAX_PATH PATH_MAX 28 #endif 29 #endif 30 #ifdef _OSK 31 #include <rbf.h> 32 #ifndef _OSK_MWC32 33 #include <modes.h> 34 #endif 35 #endif 36 #if OS2 37 #include <signal.h> 38 #endif 39 40 #if HAVE_STAT 41 #include <sys/stat.h> 42 #ifndef S_ISDIR 43 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR) 44 #endif 45 #ifndef S_ISREG 46 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG) 47 #endif 48 #endif 49 50 51 extern int force_open; 52 extern int secure; 53 extern int use_lessopen; 54 extern int ctldisp; 55 extern IFILE curr_ifile; 56 extern IFILE old_ifile; 57 #if SPACES_IN_FILENAMES 58 extern char openquote; 59 extern char closequote; 60 #endif 61 62 /* 63 * Remove quotes around a filename. 64 */ 65 public char * 66 shell_unquote(str) 67 char *str; 68 { 69 char *name; 70 char *p; 71 72 name = p = (char *) ecalloc(strlen(str)+1, sizeof(char)); 73 if (*str == openquote) 74 { 75 str++; 76 while (*str != '\0') 77 { 78 if (*str == closequote) 79 { 80 if (str[1] != closequote) 81 break; 82 str++; 83 } 84 *p++ = *str++; 85 } 86 } else 87 { 88 char *esc = get_meta_escape(); 89 int esclen = strlen(esc); 90 while (*str != '\0') 91 { 92 if (esclen > 0 && strncmp(str, esc, esclen) == 0) 93 str += esclen; 94 *p++ = *str++; 95 } 96 } 97 *p = '\0'; 98 return (name); 99 } 100 101 /* 102 * Get the shell's escape character. 103 */ 104 public char * 105 get_meta_escape() 106 { 107 char *s; 108 109 s = lgetenv("LESSMETAESCAPE"); 110 if (s == NULL) 111 s = DEF_METAESCAPE; 112 return (s); 113 } 114 115 /* 116 * Get the characters which the shell considers to be "metacharacters". 117 */ 118 static char * 119 metachars() 120 { 121 static char *mchars = NULL; 122 123 if (mchars == NULL) 124 { 125 mchars = lgetenv("LESSMETACHARS"); 126 if (mchars == NULL) 127 mchars = DEF_METACHARS; 128 } 129 return (mchars); 130 } 131 132 /* 133 * Is this a shell metacharacter? 134 */ 135 static int 136 metachar(c) 137 char c; 138 { 139 return (strchr(metachars(), c) != NULL); 140 } 141 142 /* 143 * Insert a backslash before each metacharacter in a string. 144 */ 145 public char * 146 shell_quote(s) 147 char *s; 148 { 149 char *p; 150 char *newstr; 151 int len; 152 char *esc = get_meta_escape(); 153 int esclen = strlen(esc); 154 int use_quotes = 0; 155 int have_quotes = 0; 156 157 /* 158 * Determine how big a string we need to allocate. 159 */ 160 len = 1; /* Trailing null byte */ 161 for (p = s; *p != '\0'; p++) 162 { 163 len++; 164 if (*p == openquote || *p == closequote) 165 have_quotes = 1; 166 if (metachar(*p)) 167 { 168 if (esclen == 0) 169 { 170 /* 171 * We've got a metachar, but this shell 172 * doesn't support escape chars. Use quotes. 173 */ 174 use_quotes = 1; 175 } else 176 { 177 /* 178 * Allow space for the escape char. 179 */ 180 len += esclen; 181 } 182 } 183 } 184 if (use_quotes) 185 { 186 if (have_quotes) 187 /* 188 * We can't quote a string that contains quotes. 189 */ 190 return (NULL); 191 len = strlen(s) + 3; 192 } 193 /* 194 * Allocate and construct the new string. 195 */ 196 newstr = p = (char *) ecalloc(len, sizeof(char)); 197 if (use_quotes) 198 { 199 SNPRINTF3(newstr, len, "%c%s%c", openquote, s, closequote); 200 } else 201 { 202 while (*s != '\0') 203 { 204 if (metachar(*s)) 205 { 206 /* 207 * Add the escape char. 208 */ 209 strcpy(p, esc); 210 p += esclen; 211 } 212 *p++ = *s++; 213 } 214 *p = '\0'; 215 } 216 return (newstr); 217 } 218 219 /* 220 * Return a pathname that points to a specified file in a specified directory. 221 * Return NULL if the file does not exist in the directory. 222 */ 223 static char * 224 dirfile(dirname, filename) 225 char *dirname; 226 char *filename; 227 { 228 char *pathname; 229 char *qpathname; 230 int len; 231 int f; 232 233 if (dirname == NULL || *dirname == '\0') 234 return (NULL); 235 /* 236 * Construct the full pathname. 237 */ 238 len= strlen(dirname) + strlen(filename) + 2; 239 pathname = (char *) calloc(len, sizeof(char)); 240 if (pathname == NULL) 241 return (NULL); 242 SNPRINTF3(pathname, len, "%s%s%s", dirname, PATHNAME_SEP, filename); 243 /* 244 * Make sure the file exists. 245 */ 246 qpathname = shell_unquote(pathname); 247 f = open(qpathname, OPEN_READ); 248 if (f < 0) 249 { 250 free(pathname); 251 pathname = NULL; 252 } else 253 { 254 close(f); 255 } 256 free(qpathname); 257 return (pathname); 258 } 259 260 /* 261 * Return the full pathname of the given file in the "home directory". 262 */ 263 public char * 264 homefile(filename) 265 char *filename; 266 { 267 register char *pathname; 268 269 /* 270 * Try $HOME/filename. 271 */ 272 pathname = dirfile(lgetenv("HOME"), filename); 273 if (pathname != NULL) 274 return (pathname); 275 #if OS2 276 /* 277 * Try $INIT/filename. 278 */ 279 pathname = dirfile(lgetenv("INIT"), filename); 280 if (pathname != NULL) 281 return (pathname); 282 #endif 283 #if MSDOS_COMPILER || OS2 284 /* 285 * Look for the file anywhere on search path. 286 */ 287 pathname = (char *) calloc(_MAX_PATH, sizeof(char)); 288 #if MSDOS_COMPILER==DJGPPC 289 { 290 char *res = searchpath(filename); 291 if (res == 0) 292 *pathname = '\0'; 293 else 294 strcpy(pathname, res); 295 } 296 #else 297 _searchenv(filename, "PATH", pathname); 298 #endif 299 if (*pathname != '\0') 300 return (pathname); 301 free(pathname); 302 #endif 303 return (NULL); 304 } 305 306 /* 307 * Expand a string, substituting any "%" with the current filename, 308 * and any "#" with the previous filename. 309 * But a string of N "%"s is just replaced with N-1 "%"s. 310 * Likewise for a string of N "#"s. 311 * {{ This is a lot of work just to support % and #. }} 312 */ 313 public char * 314 fexpand(s) 315 char *s; 316 { 317 register char *fr, *to; 318 register int n; 319 register char *e; 320 IFILE ifile; 321 322 #define fchar_ifile(c) \ 323 ((c) == '%' ? curr_ifile : \ 324 (c) == '#' ? old_ifile : NULL_IFILE) 325 326 /* 327 * Make one pass to see how big a buffer we 328 * need to allocate for the expanded string. 329 */ 330 n = 0; 331 for (fr = s; *fr != '\0'; fr++) 332 { 333 switch (*fr) 334 { 335 case '%': 336 case '#': 337 if (fr > s && fr[-1] == *fr) 338 { 339 /* 340 * Second (or later) char in a string 341 * of identical chars. Treat as normal. 342 */ 343 n++; 344 } else if (fr[1] != *fr) 345 { 346 /* 347 * Single char (not repeated). Treat specially. 348 */ 349 ifile = fchar_ifile(*fr); 350 if (ifile == NULL_IFILE) 351 n++; 352 else 353 n += strlen(get_filename(ifile)); 354 } 355 /* 356 * Else it is the first char in a string of 357 * identical chars. Just discard it. 358 */ 359 break; 360 default: 361 n++; 362 break; 363 } 364 } 365 366 e = (char *) ecalloc(n+1, sizeof(char)); 367 368 /* 369 * Now copy the string, expanding any "%" or "#". 370 */ 371 to = e; 372 for (fr = s; *fr != '\0'; fr++) 373 { 374 switch (*fr) 375 { 376 case '%': 377 case '#': 378 if (fr > s && fr[-1] == *fr) 379 { 380 *to++ = *fr; 381 } else if (fr[1] != *fr) 382 { 383 ifile = fchar_ifile(*fr); 384 if (ifile == NULL_IFILE) 385 *to++ = *fr; 386 else 387 { 388 strcpy(to, get_filename(ifile)); 389 to += strlen(to); 390 } 391 } 392 break; 393 default: 394 *to++ = *fr; 395 break; 396 } 397 } 398 *to = '\0'; 399 return (e); 400 } 401 402 #if TAB_COMPLETE_FILENAME 403 404 /* 405 * Return a blank-separated list of filenames which "complete" 406 * the given string. 407 */ 408 public char * 409 fcomplete(s) 410 char *s; 411 { 412 char *fpat; 413 char *qs; 414 415 if (secure) 416 return (NULL); 417 /* 418 * Complete the filename "s" by globbing "s*". 419 */ 420 #if MSDOS_COMPILER && (MSDOS_COMPILER == MSOFTC || MSDOS_COMPILER == BORLANDC) 421 /* 422 * But in DOS, we have to glob "s*.*". 423 * But if the final component of the filename already has 424 * a dot in it, just do "s*". 425 * (Thus, "FILE" is globbed as "FILE*.*", 426 * but "FILE.A" is globbed as "FILE.A*"). 427 */ 428 { 429 char *slash; 430 int len; 431 for (slash = s+strlen(s)-1; slash > s; slash--) 432 if (*slash == *PATHNAME_SEP || *slash == '/') 433 break; 434 len = strlen(s) + 4; 435 fpat = (char *) ecalloc(len, sizeof(char)); 436 if (strchr(slash, '.') == NULL) 437 SNPRINTF1(fpat, len, "%s*.*", s); 438 else 439 SNPRINTF1(fpat, len, "%s*", s); 440 } 441 #else 442 { 443 int len = strlen(s) + 2; 444 fpat = (char *) ecalloc(len, sizeof(char)); 445 SNPRINTF1(fpat, len, "%s*", s); 446 } 447 #endif 448 qs = lglob(fpat); 449 s = shell_unquote(qs); 450 if (strcmp(s,fpat) == 0) 451 { 452 /* 453 * The filename didn't expand. 454 */ 455 free(qs); 456 qs = NULL; 457 } 458 free(s); 459 free(fpat); 460 return (qs); 461 } 462 #endif 463 464 /* 465 * Try to determine if a file is "binary". 466 * This is just a guess, and we need not try too hard to make it accurate. 467 */ 468 public int 469 bin_file(f) 470 int f; 471 { 472 int i; 473 int n; 474 int bin_count = 0; 475 unsigned char data[256]; 476 477 if (!seekable(f)) 478 return (0); 479 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK) 480 return (0); 481 n = read(f, data, sizeof(data)); 482 for (i = 0; i < n; i++) 483 { 484 char c = data[i]; 485 if (ctldisp == OPT_ONPLUS && IS_CSI_START(c)) 486 { 487 while (++i < n && is_ansi_middle(data[i])) 488 continue; 489 } else if (binary_char(c)) 490 bin_count++; 491 } 492 /* 493 * Call it a binary file if there are more than 5 binary characters 494 * in the first 256 bytes of the file. 495 */ 496 return (bin_count > 5); 497 } 498 499 /* 500 * Try to determine the size of a file by seeking to the end. 501 */ 502 static POSITION 503 seek_filesize(f) 504 int f; 505 { 506 off_t spos; 507 508 spos = lseek(f, (off_t)0, SEEK_END); 509 if (spos == BAD_LSEEK) 510 return (NULL_POSITION); 511 return ((POSITION) spos); 512 } 513 514 /* 515 * Read a string from a file. 516 * Return a pointer to the string in memory. 517 */ 518 static char * 519 readfd(fd) 520 FILE *fd; 521 { 522 int len; 523 int ch; 524 char *buf; 525 char *p; 526 527 /* 528 * Make a guess about how many chars in the string 529 * and allocate a buffer to hold it. 530 */ 531 len = 100; 532 buf = (char *) ecalloc(len, sizeof(char)); 533 for (p = buf; ; p++) 534 { 535 if ((ch = getc(fd)) == '\n' || ch == EOF) 536 break; 537 if (p - buf >= len-1) 538 { 539 /* 540 * The string is too big to fit in the buffer we have. 541 * Allocate a new buffer, twice as big. 542 */ 543 len *= 2; 544 *p = '\0'; 545 p = (char *) ecalloc(len, sizeof(char)); 546 strcpy(p, buf); 547 free(buf); 548 buf = p; 549 p = buf + strlen(buf); 550 } 551 *p = ch; 552 } 553 *p = '\0'; 554 return (buf); 555 } 556 557 558 559 #if HAVE_POPEN 560 561 FILE *popen(); 562 563 /* 564 * Execute a shell command. 565 * Return a pointer to a pipe connected to the shell command's standard output. 566 */ 567 static FILE * 568 shellcmd(cmd) 569 char *cmd; 570 { 571 FILE *fd; 572 573 #if HAVE_SHELL 574 char *shell; 575 576 shell = lgetenv("SHELL"); 577 if (shell != NULL && *shell != '\0') 578 { 579 char *scmd; 580 char *esccmd; 581 582 /* 583 * Read the output of <$SHELL -c cmd>. 584 * Escape any metacharacters in the command. 585 */ 586 esccmd = shell_quote(cmd); 587 if (esccmd == NULL) 588 { 589 fd = popen(cmd, "r"); 590 } else 591 { 592 int len = strlen(shell) + strlen(esccmd) + 5; 593 scmd = (char *) ecalloc(len, sizeof(char)); 594 SNPRINTF3(scmd, len, "%s %s %s", shell, shell_coption(), esccmd); 595 free(esccmd); 596 fd = popen(scmd, "r"); 597 free(scmd); 598 } 599 } else 600 #endif 601 { 602 fd = popen(cmd, "r"); 603 } 604 /* 605 * Redirection in `popen' might have messed with the 606 * standard devices. Restore binary input mode. 607 */ 608 SET_BINARY(0); 609 return (fd); 610 } 611 612 #endif /* HAVE_POPEN */ 613 614 615 /* 616 * Expand a filename, doing any system-specific metacharacter substitutions. 617 */ 618 public char * 619 lglob(filename) 620 char *filename; 621 { 622 char *gfilename; 623 char *ofilename; 624 625 ofilename = fexpand(filename); 626 if (secure) 627 return (ofilename); 628 filename = shell_unquote(ofilename); 629 630 #ifdef DECL_GLOB_LIST 631 { 632 /* 633 * The globbing function returns a list of names. 634 */ 635 int length; 636 char *p; 637 char *qfilename; 638 DECL_GLOB_LIST(list) 639 640 GLOB_LIST(filename, list); 641 if (GLOB_LIST_FAILED(list)) 642 { 643 free(filename); 644 return (ofilename); 645 } 646 length = 1; /* Room for trailing null byte */ 647 for (SCAN_GLOB_LIST(list, p)) 648 { 649 INIT_GLOB_LIST(list, p); 650 qfilename = shell_quote(p); 651 if (qfilename != NULL) 652 { 653 length += strlen(qfilename) + 1; 654 free(qfilename); 655 } 656 } 657 gfilename = (char *) ecalloc(length, sizeof(char)); 658 for (SCAN_GLOB_LIST(list, p)) 659 { 660 INIT_GLOB_LIST(list, p); 661 qfilename = shell_quote(p); 662 if (qfilename != NULL) 663 { 664 sprintf(gfilename + strlen(gfilename), "%s ", qfilename); 665 free(qfilename); 666 } 667 } 668 /* 669 * Overwrite the final trailing space with a null terminator. 670 */ 671 *--p = '\0'; 672 GLOB_LIST_DONE(list); 673 } 674 #else 675 #ifdef DECL_GLOB_NAME 676 { 677 /* 678 * The globbing function returns a single name, and 679 * is called multiple times to walk thru all names. 680 */ 681 register char *p; 682 register int len; 683 register int n; 684 char *pathname; 685 char *qpathname; 686 DECL_GLOB_NAME(fnd,drive,dir,fname,ext,handle) 687 688 GLOB_FIRST_NAME(filename, &fnd, handle); 689 if (GLOB_FIRST_FAILED(handle)) 690 { 691 free(filename); 692 return (ofilename); 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 = strlen(drive) + strlen(dir) + strlen(fnd.GLOB_NAME) + 1; 701 pathname = (char *) ecalloc(n, sizeof(char)); 702 SNPRINTF3(pathname, n, "%s%s%s", drive, dir, fnd.GLOB_NAME); 703 qpathname = shell_quote(pathname); 704 free(pathname); 705 if (qpathname != NULL) 706 { 707 n = strlen(qpathname); 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, qpathname); 723 free(qpathname); 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 free(filename); 756 return (ofilename); 757 } 758 lessecho = lgetenv("LESSECHO"); 759 if (lessecho == NULL || *lessecho == '\0') 760 lessecho = "lessecho"; 761 /* 762 * Invoke lessecho, and read its output (a globbed list of filenames). 763 */ 764 len = strlen(lessecho) + strlen(ofilename) + (7*strlen(metachars())) + 24; 765 cmd = (char *) ecalloc(len, sizeof(char)); 766 SNPRINTF4(cmd, len, "%s -p0x%x -d0x%x -e%s ", lessecho, openquote, closequote, esc); 767 free(esc); 768 for (s = metachars(); *s != '\0'; s++) 769 sprintf(cmd + strlen(cmd), "-n0x%x ", *s); 770 sprintf(cmd + strlen(cmd), "-- %s", ofilename); 771 fd = shellcmd(cmd); 772 free(cmd); 773 if (fd == NULL) 774 { 775 /* 776 * Cannot create the pipe. 777 * Just return the original (fexpanded) filename. 778 */ 779 free(filename); 780 return (ofilename); 781 } 782 gfilename = readfd(fd); 783 pclose(fd); 784 if (*gfilename == '\0') 785 { 786 free(gfilename); 787 free(filename); 788 return (ofilename); 789 } 790 } 791 #else 792 /* 793 * No globbing functions at all. Just use the fexpanded filename. 794 */ 795 gfilename = save(filename); 796 #endif 797 #endif 798 #endif 799 free(filename); 800 free(ofilename); 801 return (gfilename); 802 } 803 804 /* 805 * See if we should open a "replacement file" 806 * instead of the file we're about to open. 807 */ 808 public char * 809 open_altfile(filename, pf, pfd) 810 char *filename; 811 int *pf; 812 void **pfd; 813 { 814 #if !HAVE_POPEN 815 return (NULL); 816 #else 817 char *lessopen; 818 char *cmd; 819 int len; 820 FILE *fd; 821 #if HAVE_FILENO 822 int returnfd = 0; 823 #endif 824 825 if (!use_lessopen || secure) 826 return (NULL); 827 ch_ungetchar(-1); 828 if ((lessopen = lgetenv("LESSOPEN")) == NULL) 829 return (NULL); 830 if (strcmp(filename, "-") == 0) 831 return (NULL); 832 if (*lessopen == '|') 833 { 834 /* 835 * If LESSOPEN starts with a |, it indicates 836 * a "pipe preprocessor". 837 */ 838 #if HAVE_FILENO 839 lessopen++; 840 returnfd = 1; 841 #else 842 error("LESSOPEN pipe is not supported", NULL_PARG); 843 return (NULL); 844 #endif 845 } 846 847 len = strlen(lessopen) + strlen(filename) + 2; 848 cmd = (char *) ecalloc(len, sizeof(char)); 849 SNPRINTF1(cmd, len, lessopen, filename); 850 fd = shellcmd(cmd); 851 free(cmd); 852 if (fd == NULL) 853 { 854 /* 855 * Cannot create the pipe. 856 */ 857 return (NULL); 858 } 859 #if HAVE_FILENO 860 if (returnfd) 861 { 862 int f; 863 char c; 864 865 /* 866 * Read one char to see if the pipe will produce any data. 867 * If it does, push the char back on the pipe. 868 */ 869 f = fileno(fd); 870 SET_BINARY(f); 871 if (read(f, &c, 1) != 1) 872 { 873 /* 874 * Pipe is empty. This means there is no alt file. 875 */ 876 pclose(fd); 877 return (NULL); 878 } 879 ch_ungetchar(c); 880 *pfd = (void *) fd; 881 *pf = f; 882 return (save("-")); 883 } 884 #endif 885 cmd = readfd(fd); 886 pclose(fd); 887 if (*cmd == '\0') 888 /* 889 * Pipe is empty. This means there is no alt file. 890 */ 891 return (NULL); 892 return (cmd); 893 #endif /* HAVE_POPEN */ 894 } 895 896 /* 897 * Close a replacement file. 898 */ 899 public void 900 close_altfile(altfilename, filename, pipefd) 901 char *altfilename; 902 char *filename; 903 void *pipefd; 904 { 905 #if HAVE_POPEN 906 char *lessclose; 907 FILE *fd; 908 char *cmd; 909 int len; 910 911 if (secure) 912 return; 913 if (pipefd != NULL) 914 { 915 #if OS2 916 /* 917 * The pclose function of OS/2 emx sometimes fails. 918 * Send SIGINT to the piped process before closing it. 919 */ 920 kill(((FILE*)pipefd)->_pid, SIGINT); 921 #endif 922 pclose((FILE*) pipefd); 923 } 924 if ((lessclose = lgetenv("LESSCLOSE")) == NULL) 925 return; 926 len = strlen(lessclose) + strlen(filename) + strlen(altfilename) + 2; 927 cmd = (char *) ecalloc(len, sizeof(char)); 928 SNPRINTF2(cmd, len, lessclose, filename, altfilename); 929 fd = shellcmd(cmd); 930 free(cmd); 931 if (fd != NULL) 932 pclose(fd); 933 #endif 934 } 935 936 /* 937 * Is the specified file a directory? 938 */ 939 public int 940 is_dir(filename) 941 char *filename; 942 { 943 int isdir = 0; 944 945 filename = shell_unquote(filename); 946 #if HAVE_STAT 947 { 948 int r; 949 struct stat statbuf; 950 951 r = stat(filename, &statbuf); 952 isdir = (r >= 0 && S_ISDIR(statbuf.st_mode)); 953 } 954 #else 955 #ifdef _OSK 956 { 957 register int f; 958 959 f = open(filename, S_IREAD | S_IFDIR); 960 if (f >= 0) 961 close(f); 962 isdir = (f >= 0); 963 } 964 #endif 965 #endif 966 free(filename); 967 return (isdir); 968 } 969 970 /* 971 * Returns NULL if the file can be opened and 972 * is an ordinary file, otherwise an error message 973 * (if it cannot be opened or is a directory, etc.) 974 */ 975 public char * 976 bad_file(filename) 977 char *filename; 978 { 979 register char *m = NULL; 980 981 filename = shell_unquote(filename); 982 if (!force_open && is_dir(filename)) 983 { 984 static char is_a_dir[] = " is a directory"; 985 986 m = (char *) ecalloc(strlen(filename) + sizeof(is_a_dir), 987 sizeof(char)); 988 strcpy(m, filename); 989 strcat(m, is_a_dir); 990 } else 991 { 992 #if HAVE_STAT 993 int r; 994 struct stat statbuf; 995 996 r = stat(filename, &statbuf); 997 if (r < 0) 998 { 999 m = errno_message(filename); 1000 } else if (force_open) 1001 { 1002 m = NULL; 1003 } else if (!S_ISREG(statbuf.st_mode)) 1004 { 1005 static char not_reg[] = " is not a regular file (use -f to see it)"; 1006 m = (char *) ecalloc(strlen(filename) + sizeof(not_reg), 1007 sizeof(char)); 1008 strcpy(m, filename); 1009 strcat(m, not_reg); 1010 } 1011 #endif 1012 } 1013 free(filename); 1014 return (m); 1015 } 1016 1017 /* 1018 * Return the size of a file, as cheaply as possible. 1019 * In Unix, we can stat the file. 1020 */ 1021 public POSITION 1022 filesize(f) 1023 int f; 1024 { 1025 #if HAVE_STAT 1026 struct stat statbuf; 1027 1028 if (fstat(f, &statbuf) >= 0) 1029 return ((POSITION) statbuf.st_size); 1030 #else 1031 #ifdef _OSK 1032 long size; 1033 1034 if ((size = (long) _gs_size(f)) >= 0) 1035 return ((POSITION) size); 1036 #endif 1037 #endif 1038 return (seek_filesize(f)); 1039 } 1040 1041 /* 1042 * 1043 */ 1044 public char * 1045 shell_coption() 1046 { 1047 return ("-c"); 1048 } 1049