1/*
2 * Copyright (C) 1984-2000 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
51extern int force_open;
52extern int secure;
53extern IFILE curr_ifile;
54extern IFILE old_ifile;
55#if SPACES_IN_FILENAMES
56extern char openquote;
57extern char closequote;
58#endif
59
60/*
61 * Remove quotes around a filename.
62 */
63 public char *
64unquote_file(str)
65 char *str;
66{
67#if SPACES_IN_FILENAMES
68 char *name;
69 char *p;
70
71 if (*str != openquote)
72 return (save(str));
73 name = (char *) ecalloc(strlen(str), sizeof(char));
74 strcpy(name, str+1);
75 p = name + strlen(name) - 1;
76 if (*p == closequote)
77 *p = '\0';
78 return (name);
79#else
80 return (save(str));
81#endif
82}
83
84/*
85 * Return a pathname that points to a specified file in a specified directory.
86 * Return NULL if the file does not exist in the directory.
87 */
88 static char *
89dirfile(dirname, filename)
90 char *dirname;
91 char *filename;
92{
93 char *pathname;
94 char *qpathname;
95 int f;
96
97 if (dirname == NULL || *dirname == '\0')
98 return (NULL);
99 /*
100 * Construct the full pathname.
101 */
102 pathname = (char *) calloc(strlen(dirname) + strlen(filename) + 2,
103 sizeof(char));
104 if (pathname == NULL)
105 return (NULL);
106 sprintf(pathname, "%s%s%s", dirname, PATHNAME_SEP, filename);
107 /*
108 * Make sure the file exists.
109 */
110 qpathname = unquote_file(pathname);
111 f = open(qpathname, OPEN_READ);
112 if (f < 0)
113 {
114 free(pathname);
115 pathname = NULL;
116 } else
117 {
118 close(f);
119 }
120 free(qpathname);
121 return (pathname);
122}
123
124/*
125 * Return the full pathname of the given file in the "home directory".
126 */
127 public char *
128homefile(filename)
129 char *filename;
130{
131 register char *pathname;
132
133 /*
134 * Try $HOME/filename.
135 */
136 pathname = dirfile(lgetenv("HOME"), filename);
137 if (pathname != NULL)
138 return (pathname);
139#if OS2
140 /*
141 * Try $INIT/filename.
142 */
143 pathname = dirfile(lgetenv("INIT"), filename);
144 if (pathname != NULL)
145 return (pathname);
146#endif
147#if MSDOS_COMPILER || OS2
148 /*
149 * Look for the file anywhere on search path.
150 */
151 pathname = (char *) calloc(_MAX_PATH, sizeof(char));
152#if MSDOS_COMPILER==DJGPPC
153 {
154 char *res = searchpath(filename);
155 if (res == 0)
156 *pathname = '\0';
157 else
158 strcpy(pathname, res);
159 }
160#else
161 _searchenv(filename, "PATH", pathname);
162#endif
163 if (*pathname != '\0')
164 return (pathname);
165 free(pathname);
166#endif
167 return (NULL);
168}
169
170/*
171 * Expand a string, substituting any "%" with the current filename,
172 * and any "#" with the previous filename.
173 * But a string of N "%"s is just replaced with N-1 "%"s.
174 * Likewise for a string of N "#"s.
175 * {{ This is a lot of work just to support % and #. }}
176 */
177 public char *
178fexpand(s)
179 char *s;
180{
181 register char *fr, *to;
182 register int n;
183 register char *e;
184 IFILE ifile;
185
186#define fchar_ifile(c) \
187 ((c) == '%' ? curr_ifile : \
188 (c) == '#' ? old_ifile : NULL_IFILE)
189
190 /*
191 * Make one pass to see how big a buffer we
192 * need to allocate for the expanded string.
193 */
194 n = 0;
195 for (fr = s; *fr != '\0'; fr++)
196 {
197 switch (*fr)
198 {
199 case '%':
200 case '#':
201 if (fr > s && fr[-1] == *fr)
202 {
203 /*
204 * Second (or later) char in a string
205 * of identical chars. Treat as normal.
206 */
207 n++;
208 } else if (fr[1] != *fr)
209 {
210 /*
211 * Single char (not repeated). Treat specially.
212 */
213 ifile = fchar_ifile(*fr);
214 if (ifile == NULL_IFILE)
215 n++;
216 else
217 n += strlen(get_filename(ifile));
218 }
219 /*
220 * Else it is the first char in a string of
221 * identical chars. Just discard it.
222 */
223 break;
224 default:
225 n++;
226 break;
227 }
228 }
229
230 e = (char *) ecalloc(n+1, sizeof(char));
231
232 /*
233 * Now copy the string, expanding any "%" or "#".
234 */
235 to = e;
236 for (fr = s; *fr != '\0'; fr++)
237 {
238 switch (*fr)
239 {
240 case '%':
241 case '#':
242 if (fr > s && fr[-1] == *fr)
243 {
244 *to++ = *fr;
245 } else if (fr[1] != *fr)
246 {
247 ifile = fchar_ifile(*fr);
248 if (ifile == NULL_IFILE)
249 *to++ = *fr;
250 else
251 {
252 strcpy(to, get_filename(ifile));
253 to += strlen(to);
254 }
255 }
256 break;
257 default:
258 *to++ = *fr;
259 break;
260 }
261 }
262 *to = '\0';
263 return (e);
264}
265
266#if TAB_COMPLETE_FILENAME
267
268/*
269 * Return a blank-separated list of filenames which "complete"
270 * the given string.
271 */
272 public char *
273fcomplete(s)
274 char *s;
275{
276 char *fpat;
277
278 if (secure)
279 return (NULL);
280 /*
281 * Complete the filename "s" by globbing "s*".
282 */
283#if MSDOS_COMPILER && (MSDOS_COMPILER == MSOFTC || MSDOS_COMPILER == BORLANDC)
284 /*
285 * But in DOS, we have to glob "s*.*".
286 * But if the final component of the filename already has
287 * a dot in it, just do "s*".
288 * (Thus, "FILE" is globbed as "FILE*.*",
289 * but "FILE.A" is globbed as "FILE.A*").
290 */
291 {
292 char *slash;
293 for (slash = s+strlen(s)-1; slash > s; slash--)
294 if (*slash == *PATHNAME_SEP || *slash == '/')
295 break;
296 fpat = (char *) ecalloc(strlen(s)+4, sizeof(char));
297 if (strchr(slash, '.') == NULL)
298 sprintf(fpat, "%s*.*", s);
299 else
300 sprintf(fpat, "%s*", s);
301 }
302#else
303 fpat = (char *) ecalloc(strlen(s)+2, sizeof(char));
304 sprintf(fpat, "%s*", s);
305#endif
306 s = lglob(fpat);
307 if (strcmp(s,fpat) == 0)
308 {
309 /*
310 * The filename didn't expand.
311 */
312 free(s);
313 s = NULL;
314 }
315 free(fpat);
316 return (s);
317}
318#endif
319
320/*
321 * Try to determine if a file is "binary".
322 * This is just a guess, and we need not try too hard to make it accurate.
323 */
324 public int
325bin_file(f)
326 int f;
327{
328 int i;
329 int n;
330 unsigned char data[64];
331
332 if (!seekable(f))
333 return (0);
334 if (lseek(f, (off_t)0, 0) == BAD_LSEEK)
335 return (0);
336 n = read(f, data, sizeof(data));
337 for (i = 0; i < n; i++)
338 if (binary_char(data[i]))
339 return (1);
340 return (0);
341}
342
343/*
344 * Try to determine the size of a file by seeking to the end.
345 */
346 static POSITION
347seek_filesize(f)
348 int f;
349{
350 off_t spos;
351
352 spos = lseek(f, (off_t)0, 2);
353 if (spos == BAD_LSEEK)
354 return (NULL_POSITION);
355 return ((POSITION) spos);
356}
357
358/*
359 * Read a string from a file.
360 * Return a pointer to the string in memory.
361 */
362 static char *
363readfd(fd)
364 FILE *fd;
365{
366 int len;
367 int ch;
368 char *buf;
369 char *p;
370
371 /*
372 * Make a guess about how many chars in the string
373 * and allocate a buffer to hold it.
374 */
375 len = 100;
376 buf = (char *) ecalloc(len, sizeof(char));
377 for (p = buf; ; p++)
378 {
379 if ((ch = getc(fd)) == '\n' || ch == EOF)
380 break;
381 if (p - buf >= len-1)
382 {
383 /*
384 * The string is too big to fit in the buffer we have.
385 * Allocate a new buffer, twice as big.
386 */
387 len *= 2;
388 *p = '\0';
389 p = (char *) ecalloc(len, sizeof(char));
390 strcpy(p, buf);
391 free(buf);
392 buf = p;
393 p = buf + strlen(buf);
394 }
395 *p = ch;
396 }
397 *p = '\0';
398 return (buf);
399}
400
401#if HAVE_SHELL
402
403/*
404 * Get the shell's escape character.
405 */
406 static char *
407get_meta_escape()
408{
409 char *s;
410
411 s = lgetenv("LESSMETAESCAPE");
412 if (s == NULL)
413 s = DEF_METAESCAPE;
414 return (s);
415}
416
417/*
418 * Is this a shell metacharacter?
419 */
420 static int
421metachar(c)
422 char c;
423{
424 static char *metachars = NULL;
425
426 if (metachars == NULL)
427 {
428 metachars = lgetenv("LESSMETACHARS");
429 if (metachars == NULL)
430 metachars = DEF_METACHARS;
431 }
432 return (strchr(metachars, c) != NULL);
433}
434
435/*
436 * Insert a backslash before each metacharacter in a string.
437 */
438 public char *
439esc_metachars(s)
440 char *s;
441{
442 char *p;
443 char *newstr;
444 int len;
445 char *esc;
446 int esclen;
447
448 /*
449 * Determine how big a string we need to allocate.
450 */
451 esc = get_meta_escape();
452 esclen = strlen(esc);
453 len = 1; /* Trailing null byte */
454 for (p = s; *p != '\0'; p++)
455 {
456 len++;
457 if (metachar(*p))
458 {
459 if (*esc == '\0')
460 {
461 /*
462 * We've got a metachar, but this shell
463 * doesn't support escape chars. Give up.
464 */
465 return (NULL);
466 }
467 /*
468 * Allow space for the escape char.
469 */
470 len += esclen;
471 }
472 }
473 /*
474 * Allocate and construct the new string.
475 */
476 newstr = p = (char *) ecalloc(len, sizeof(char));
477 while (*s != '\0')
478 {
479 if (metachar(*s))
480 {
481 /*
482 * Add the escape char.
483 */
484 strcpy(p, esc);
485 p += esclen;
486 }
487 *p++ = *s++;
488 }
489 *p = '\0';
490 return (newstr);
491}
492
493#else /* HAVE_SHELL */
494
495 public char *
496esc_metachars(s)
497 char *s;
498{
499 return (save(s));
500}
501
502#endif /* HAVE_SHELL */
503
504
505#if HAVE_POPEN
506
507FILE *popen();
508
509/*
510 * Execute a shell command.
511 * Return a pointer to a pipe connected to the shell command's standard output.
512 */
513 static FILE *
514shellcmd(cmd)
515 char *cmd;
516{
517 FILE *fd;
518
519#if HAVE_SHELL
520 char *shell;
521
522 shell = lgetenv("SHELL");
523 if (shell != NULL && *shell != '\0')
524 {
525 char *scmd;
526 char *esccmd;
527
528 /*
529 * Try to escape any metacharacters in the command.
530 * If we can't do that, just put the command in quotes.
531 * (But that doesn't work well if the command itself
532 * contains quotes.)
533 */
534 if ((esccmd = esc_metachars(cmd)) == NULL)
535 {
536 /*
537 * Cannot escape the metacharacters, so use quotes.
538 * Read the output of <$SHELL -c "cmd">.
539 */
540 scmd = (char *) ecalloc(strlen(shell) + strlen(cmd) + 7,
541 sizeof(char));
542 sprintf(scmd, "%s -c \"%s\"", shell, cmd);
543 } else
544 {
545 /*
546 * Read the output of <$SHELL -c cmd>.
547 * No quotes; use the escaped cmd.
548 */
549 scmd = (char *) ecalloc(strlen(shell) + strlen(esccmd) + 5,
550 sizeof(char));
551 sprintf(scmd, "%s -c %s", shell, esccmd);
552 free(esccmd);
553 }
554 fd = popen(scmd, "r");
555 free(scmd);
556 } else
557#endif
558 {
559 fd = popen(cmd, "r");
560 /*
561 * Redirection in `popen' might have messed with the
562 * standard devices. Restore binary input mode.
563 */
564 SET_BINARY(0);
565 }
566 return (fd);
567}
568
569#endif /* HAVE_POPEN */
570
571
572/*
573 * Expand a filename, doing any system-specific metacharacter substitutions.
574 */
575 public char *
576lglob(filename)
577 char *filename;
578{
579 char *gfilename;
580 char *ofilename;
581
582 ofilename = fexpand(filename);
583 if (secure)
584 return (ofilename);
585 filename = unquote_file(ofilename);
586
587#ifdef DECL_GLOB_LIST
588{
589 /*
590 * The globbing function returns a list of names.
591 */
592 int length;
593 char *p;
594 DECL_GLOB_LIST(list)
595
596 GLOB_LIST(filename, list);
597 if (GLOB_LIST_FAILED(list))
598 {
599 free(filename);
600 return (ofilename);
601 }
602 length = 1; /* Room for trailing null byte */
603 for (SCAN_GLOB_LIST(list, p))
604 {
605 INIT_GLOB_LIST(list, p);
606 length += strlen(p) + 1;
607#if SPACES_IN_FILENAMES
608 if (strchr(p, ' ') != NULL)
609 length += 2; /* Allow for quotes */
610#endif
611 }
612 gfilename = (char *) ecalloc(length, sizeof(char));
613 for (SCAN_GLOB_LIST(list, p))
614 {
615 INIT_GLOB_LIST(list, p);
616#if SPACES_IN_FILENAMES
617 if (strchr(p, ' ') != NULL)
618 sprintf(gfilename + strlen(gfilename), "%c%s%c ",
619 openquote, p, closequote);
620 else
621#endif
622 sprintf(gfilename + strlen(gfilename), "%s ", p);
623 }
624 /*
625 * Overwrite the final trailing space with a null terminator.
626 */
627 *--p = '\0';
628 GLOB_LIST_DONE(list);
629}
630#else
631#ifdef DECL_GLOB_NAME
632{
633 /*
634 * The globbing function returns a single name, and
635 * is called multiple times to walk thru all names.
636 */
637 register char *p;
638 register int len;
639 register int n;
640#if SPACES_IN_FILENAMES
641 register int spaces_in_file;
642#endif
643 DECL_GLOB_NAME(fnd,drive,dir,fname,ext,handle)
644
645 GLOB_FIRST_NAME(filename, &fnd, handle);
646 if (GLOB_FIRST_FAILED(handle))
647 {
648 free(filename);
649 return (ofilename);
650 }
651
652 _splitpath(filename, drive, dir, fname, ext);
653 len = 100;
654 gfilename = (char *) ecalloc(len, sizeof(char));
655 p = gfilename;
656 do {
657 n = strlen(drive) + strlen(dir) + strlen(fnd.GLOB_NAME) + 1;
658#if SPACES_IN_FILENAMES
659 spaces_in_file = 0;
660 if (strchr(fnd.GLOB_NAME, ' ') != NULL ||
661 strchr(filename, ' ') != NULL)
662 {
663 spaces_in_file = 1;
664 n += 2;
665 }
666#endif
667 while (p - gfilename + n+2 >= len)
668 {
669 /*
670 * No room in current buffer. Allocate a bigger one.
671 */
672 len *= 2;
673 *p = '\0';
674 p = (char *) ecalloc(len, sizeof(char));
675 strcpy(p, gfilename);
676 free(gfilename);
677 gfilename = p;
678 p = gfilename + strlen(gfilename);
679 }
680#if SPACES_IN_FILENAMES
681 if (spaces_in_file)
682 sprintf(p, "%c%s%s%s%c ", openquote,
683 drive, dir, fnd.GLOB_NAME, closequote);
684 else
685#endif
686 sprintf(p, "%s%s%s ", drive, dir, fnd.GLOB_NAME);
687 p += n;
688 } while (GLOB_NEXT_NAME(handle, &fnd) == 0);
689
690 /*
691 * Overwrite the final trailing space with a null terminator.
692 */
693 *--p = '\0';
694 GLOB_NAME_DONE(handle);
695}
696#else
697#if HAVE_POPEN
698{
699 /*
700 * We get the shell to glob the filename for us by passing
701 * an "echo" command to the shell and reading its output.
702 */
703 FILE *fd;
704 char *s;
705 char *lessecho;
706 char *cmd;
707
708 lessecho = lgetenv("LESSECHO");
709 if (lessecho == NULL || *lessecho == '\0')
710 lessecho = "lessecho";
711 s = esc_metachars(filename);
712 if (s == NULL)
713 {
714 /*
715 * There may be dangerous metachars in this name.
716 * We can't risk passing it to the shell.
717 * {{ For example, do "!;TAB" when the first file
718 * in the dir is named "rm". }}
719 */
720 free(filename);
721 return (ofilename);
722 }
723 /*
724 * Invoke lessecho, and read its output (a globbed list of filenames).
725 */
726 cmd = (char *) ecalloc(strlen(lessecho) + strlen(s) + 24, sizeof(char));
727 sprintf(cmd, "%s -p0x%x -d0x%x -- %s",
728 lessecho, openquote, closequote, s);
729 fd = shellcmd(cmd);
730 free(s);
731 free(cmd);
732 if (fd == NULL)
733 {
734 /*
735 * Cannot create the pipe.
736 * Just return the original (fexpanded) filename.
737 */
738 free(filename);
739 return (ofilename);
740 }
741 gfilename = readfd(fd);
742 pclose(fd);
743 if (*gfilename == '\0')
744 {
745 free(gfilename);
746 free(filename);
747 return (ofilename);
748 }
749}
750#else
751 /*
752 * No globbing functions at all. Just use the fexpanded filename.
753 */
754 gfilename = save(filename);
755#endif
756#endif
757#endif
758 free(filename);
759 free(ofilename);
760 return (gfilename);
761}
762
763/*
764 * See if we should open a "replacement file"
765 * instead of the file we're about to open.
766 */
767 public char *
768open_altfile(filename, pf, pfd)
769 char *filename;
770 int *pf;
771 void **pfd;
772{
773#if !HAVE_POPEN
774 return (NULL);
775#else
776 char *lessopen;
777 char *gfilename;
778 char *cmd;
779 FILE *fd;
780#if HAVE_FILENO
781 int returnfd = 0;
782#endif
783
784 if (secure)
785 return (NULL);
786 ch_ungetchar(-1);
787 if ((lessopen = lgetenv("LESSOPEN")) == NULL)
788 return (NULL);
789 if (strcmp(filename, "-") == 0)
790 return (NULL);
791 if (*lessopen == '|')
792 {
793 /*
794 * If LESSOPEN starts with a |, it indicates
795 * a "pipe preprocessor".
796 */
797#if HAVE_FILENO
798 lessopen++;
799 returnfd = 1;
800#else
801 error("LESSOPEN pipe is not supported", NULL_PARG);
802 return (NULL);
803#endif
804 }
805
806 gfilename = esc_metachars(filename);
807 if (gfilename == NULL)
808 {
809 /*
810 * Cannot escape metacharacters.
811 */
812 return (NULL);
813 }
814 cmd = (char *) ecalloc(strlen(lessopen) + strlen(gfilename) + 2,
815 sizeof(char));
816 sprintf(cmd, lessopen, gfilename);
817 fd = shellcmd(cmd);
818 free(gfilename);
819 free(cmd);
820 if (fd == NULL)
821 {
822 /*
823 * Cannot create the pipe.
824 */
825 return (NULL);
826 }
827#if HAVE_FILENO
828 if (returnfd)
829 {
830 int f;
831 char c;
832
833 /*
834 * Read one char to see if the pipe will produce any data.
835 * If it does, push the char back on the pipe.
836 */
837 f = fileno(fd);
838 SET_BINARY(f);
839 if (read(f, &c, 1) != 1)
840 {
841 /*
842 * Pipe is empty. This means there is no alt file.
843 */
844 pclose(fd);
845 return (NULL);
846 }
847 ch_ungetchar(c);
848 *pfd = (void *) fd;
849 *pf = f;
850 return (save("-"));
851 }
852#endif
853 gfilename = readfd(fd);
854 pclose(fd);
855 if (*gfilename == '\0')
856 /*
857 * Pipe is empty. This means there is no alt file.
858 */
859 return (NULL);
860 return (gfilename);
861#endif /* HAVE_POPEN */
862}
863
864/*
865 * Close a replacement file.
866 */
867 public void
868close_altfile(altfilename, filename, pipefd)
869 char *altfilename;
870 char *filename;
871 void *pipefd;
872{
873#if HAVE_POPEN
874 char *lessclose;
875 char *gfilename;
876 char *galtfilename;
877 FILE *fd;
878 char *cmd;
879
880 if (secure)
881 return;
882 if (pipefd != NULL)
883 {
884#if OS2
885 /*
886 * The pclose function of OS/2 emx sometimes fails.
887 * Send SIGINT to the piped process before closing it.
888 */
889 kill(((FILE*)pipefd)->_pid, SIGINT);
890#endif
891 pclose((FILE*) pipefd);
892 }
893 if ((lessclose = lgetenv("LESSCLOSE")) == NULL)
894 return;
895 gfilename = esc_metachars(filename);
896 if (gfilename == NULL)
897 {
898 return;
899 }
900 galtfilename = esc_metachars(altfilename);
901 if (galtfilename == NULL)
902 {
903 free(gfilename);
904 return;
905 }
906 cmd = (char *) ecalloc(strlen(lessclose) + strlen(gfilename) +
907 strlen(galtfilename) + 2, sizeof(char));
908 sprintf(cmd, lessclose, gfilename, galtfilename);
909 fd = shellcmd(cmd);
910 free(galtfilename);
911 free(gfilename);
912 free(cmd);
913 if (fd != NULL)
914 pclose(fd);
915#endif
916}
917
918/*
919 * Is the specified file a directory?
920 */
921 public int
922is_dir(filename)
923 char *filename;
924{
925 int isdir = 0;
926
927 filename = unquote_file(filename);
928#if HAVE_STAT
929{
930 int r;
931 struct stat statbuf;
932
933 r = stat(filename, &statbuf);
934 isdir = (r >= 0 && S_ISDIR(statbuf.st_mode));
935}
936#else
937#ifdef _OSK
938{
939 register int f;
940
941 f = open(filename, S_IREAD | S_IFDIR);
942 if (f >= 0)
943 close(f);
944 isdir = (f >= 0);
945}
946#endif
947#endif
948 free(filename);
949 return (isdir);
950}
951
952/*
953 * Returns NULL if the file can be opened and
954 * is an ordinary file, otherwise an error message
955 * (if it cannot be opened or is a directory, etc.)
956 */
957 public char *
958bad_file(filename)
959 char *filename;
960{
961 register char *m = NULL;
962
963 filename = unquote_file(filename);
964 if (is_dir(filename))
965 {
966 static char is_dir[] = " is a directory";
967
968 m = (char *) ecalloc(strlen(filename) + sizeof(is_dir),
969 sizeof(char));
970 strcpy(m, filename);
971 strcat(m, is_dir);
972 } else
973 {
974#if HAVE_STAT
975 int r;
976 struct stat statbuf;
977
978 r = stat(filename, &statbuf);
979 if (r < 0)
980 {
981 m = errno_message(filename);
982 } else if (force_open)
983 {
984 m = NULL;
985 } else if (!S_ISREG(statbuf.st_mode))
986 {
987 static char not_reg[] = " is not a regular file (use -f to see it)";
988 m = (char *) ecalloc(strlen(filename) + sizeof(not_reg),
989 sizeof(char));
990 strcpy(m, filename);
991 strcat(m, not_reg);
992 }
993#endif
994 }
995 free(filename);
996 return (m);
997}
998
999/*
1000 * Return the size of a file, as cheaply as possible.
1001 * In Unix, we can stat the file.
1002 */
1003 public POSITION
1004filesize(f)
1005 int f;
1006{
1007#if HAVE_STAT
1008 struct stat statbuf;
1009
1010 if (fstat(f, &statbuf) >= 0)
1011 return ((POSITION) statbuf.st_size);
1012#else
1013#ifdef _OSK
1014 long size;
1015
1016 if ((size = (long) _gs_size(f)) >= 0)
1017 return ((POSITION) size);
1018#endif
1019#endif
1020 return (seek_filesize(f));
1021}
1022