2 * Copyright (C) 1984-2021 Mark Nudelman
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.
7 * For more information, see the README file.
12 * Routines to mess around with filenames (and files).
13 * Much of this is very OS dependent.
20 #if MSDOS_COMPILER==WIN32C && !defined(_MSC_VER)
23 #if MSDOS_COMPILER==DJGPPC
26 #define _MAX_PATH PATH_MAX
39 #define S_ISDIR(m) (((m) & S_IFMT) == S_IFDIR)
42 #define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
46 extern int force_open;
48 extern int use_lessopen;
51 extern IFILE curr_ifile;
52 extern IFILE old_ifile;
53 #if SPACES_IN_FILENAMES
54 extern char openquote;
55 extern char closequote;
59 * Remove quotes around a filename.
68 name = p = (char *) ecalloc(strlen(str)+1, sizeof(char));
69 if (*str == openquote)
74 if (*str == closequote)
76 if (str[1] != closequote)
84 char *esc = get_meta_escape();
85 int esclen = (int) strlen(esc);
88 if (esclen > 0 && strncmp(str, esc, esclen) == 0)
98 * Get the shell's escape character.
101 get_meta_escape(VOID_PARAM)
105 s = lgetenv("LESSMETAESCAPE");
112 * Get the characters which the shell considers to be "metacharacters".
115 metachars(VOID_PARAM)
117 static char *mchars = NULL;
121 mchars = lgetenv("LESSMETACHARS");
123 mchars = DEF_METACHARS;
129 * Is this a shell metacharacter?
135 return (strchr(metachars(), c) != NULL);
139 * Insert a backslash before each metacharacter in a string.
148 char *esc = get_meta_escape();
149 int esclen = (int) strlen(esc);
154 * Determine how big a string we need to allocate.
156 len = 1; /* Trailing null byte */
157 for (p = s; *p != '\0'; p++)
160 if (*p == openquote || *p == closequote)
167 * We've got a metachar, but this shell
168 * doesn't support escape chars. Use quotes.
174 * Allow space for the escape char.
184 * We can't quote a string that contains quotes.
187 len = (int) strlen(s) + 3;
190 * Allocate and construct the new string.
192 newstr = p = (char *) ecalloc(len, sizeof(char));
195 SNPRINTF3(newstr, len, "%c%s%c", openquote, s, closequote);
203 * Add the escape char.
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.
220 dirfile(dirname, filename)
228 if (dirname == NULL || *dirname == '\0')
231 * Construct the full pathname.
233 len = (int) (strlen(dirname) + strlen(filename) + 2);
234 pathname = (char *) calloc(len, sizeof(char));
235 if (pathname == NULL)
237 SNPRINTF3(pathname, len, "%s%s%s", dirname, PATHNAME_SEP, filename);
239 * Make sure the file exists.
241 f = open(pathname, OPEN_READ);
254 * Return the full pathname of the given file in the "home directory".
263 * Try $HOME/filename.
265 pathname = dirfile(lgetenv("HOME"), filename);
266 if (pathname != NULL)
270 * Try $INIT/filename.
272 pathname = dirfile(lgetenv("INIT"), filename);
273 if (pathname != NULL)
276 #if MSDOS_COMPILER || OS2
278 * Look for the file anywhere on search path.
280 pathname = (char *) calloc(_MAX_PATH, sizeof(char));
281 #if MSDOS_COMPILER==DJGPPC
283 char *res = searchpath(filename);
287 strcpy(pathname, res);
290 _searchenv(filename, "PATH", pathname);
292 if (*pathname != '\0')
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 #. }}
315 #define fchar_ifile(c) \
316 ((c) == '%' ? curr_ifile : \
317 (c) == '#' ? old_ifile : NULL_IFILE)
320 * Make one pass to see how big a buffer we
321 * need to allocate for the expanded string.
324 for (fr = s; *fr != '\0'; fr++)
330 if (fr > s && fr[-1] == *fr)
333 * Second (or later) char in a string
334 * of identical chars. Treat as normal.
337 } else if (fr[1] != *fr)
340 * Single char (not repeated). Treat specially.
342 ifile = fchar_ifile(*fr);
343 if (ifile == NULL_IFILE)
346 n += (int) strlen(get_filename(ifile));
349 * Else it is the first char in a string of
350 * identical chars. Just discard it.
359 e = (char *) ecalloc(n+1, sizeof(char));
362 * Now copy the string, expanding any "%" or "#".
365 for (fr = s; *fr != '\0'; fr++)
371 if (fr > s && fr[-1] == *fr)
374 } else if (fr[1] != *fr)
376 ifile = fchar_ifile(*fr);
377 if (ifile == NULL_IFILE)
381 strcpy(to, get_filename(ifile));
396 #if TAB_COMPLETE_FILENAME
399 * Return a blank-separated list of filenames which "complete"
412 * Complete the filename "s" by globbing "s*".
414 #if MSDOS_COMPILER && (MSDOS_COMPILER == MSOFTC || MSDOS_COMPILER == BORLANDC)
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*").
425 for (slash = s+strlen(s)-1; slash > s; slash--)
426 if (*slash == *PATHNAME_SEP || *slash == '/')
428 len = (int) strlen(s) + 4;
429 fpat = (char *) ecalloc(len, sizeof(char));
430 if (strchr(slash, '.') == NULL)
431 SNPRINTF1(fpat, len, "%s*.*", s);
433 SNPRINTF1(fpat, len, "%s*", s);
437 int len = (int) strlen(s) + 2;
438 fpat = (char *) ecalloc(len, sizeof(char));
439 SNPRINTF1(fpat, len, "%s*", s);
443 s = shell_unquote(qs);
444 if (strcmp(s,fpat) == 0)
447 * The filename didn't expand.
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.
474 if (lseek(f, (off_t)0, SEEK_SET) == BAD_LSEEK)
476 n = read(f, data, sizeof(data));
480 for (p = data; p < edata; )
482 if (utf_mode && !is_utf8_well_formed(p, edata-data))
485 utf_skip_to_lead(&p, edata);
488 LWCHAR c = step_char(&p, +1, edata);
489 struct ansi_state *pansi;
490 if (ctldisp == OPT_ONPLUS && (pansi = ansi_start(c)) != NULL)
492 skip_ansi(pansi, &p, edata);
494 } else if (binary_char(c))
499 * Call it a binary file if there are more than 5 binary characters
500 * in the first 256 bytes of the file.
502 return (bin_count > 5);
506 * Try to determine the size of a file by seeking to the end.
514 spos = lseek(f, (off_t)0, SEEK_END);
515 if (spos == BAD_LSEEK)
516 return (NULL_POSITION);
517 return ((POSITION) spos);
521 * Read a string from a file.
522 * Return a pointer to the string in memory.
534 * Make a guess about how many chars in the string
535 * and allocate a buffer to hold it.
538 buf = (char *) ecalloc(len, sizeof(char));
541 if ((ch = getc(fd)) == '\n' || ch == EOF)
543 if (p - buf >= len-1)
546 * The string is too big to fit in the buffer we have.
547 * Allocate a new buffer, twice as big.
551 p = (char *) ecalloc(len, sizeof(char));
555 p = buf + strlen(buf);
568 * Execute a shell command.
569 * Return a pointer to a pipe connected to the shell command's standard output.
580 shell = lgetenv("SHELL");
581 if (!isnullenv(shell))
587 * Read the output of <$SHELL -c cmd>.
588 * Escape any metacharacters in the command.
590 esccmd = shell_quote(cmd);
593 fd = popen(cmd, "r");
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);
600 fd = popen(scmd, "r");
606 fd = popen(cmd, "r");
609 * Redirection in `popen' might have messed with the
610 * standard devices. Restore binary input mode.
616 #endif /* HAVE_POPEN */
620 * Expand a filename, doing any system-specific metacharacter substitutions.
628 filename = fexpand(filename);
632 #ifdef DECL_GLOB_LIST
635 * The globbing function returns a list of names.
642 GLOB_LIST(filename, list);
643 if (GLOB_LIST_FAILED(list))
647 length = 1; /* Room for trailing null byte */
648 for (SCAN_GLOB_LIST(list, p))
650 INIT_GLOB_LIST(list, p);
651 qfilename = shell_quote(p);
652 if (qfilename != NULL)
654 length += strlen(qfilename) + 1;
658 gfilename = (char *) ecalloc(length, sizeof(char));
659 for (SCAN_GLOB_LIST(list, p))
661 INIT_GLOB_LIST(list, p);
662 qfilename = shell_quote(p);
663 if (qfilename != NULL)
665 sprintf(gfilename + strlen(gfilename), "%s ", qfilename);
670 * Overwrite the final trailing space with a null terminator.
673 GLOB_LIST_DONE(list);
676 #ifdef DECL_GLOB_NAME
679 * The globbing function returns a single name, and
680 * is called multiple times to walk thru all names.
687 DECL_GLOB_NAME(fnd,drive,dir,fname,ext,handle)
689 GLOB_FIRST_NAME(filename, &fnd, handle);
690 if (GLOB_FIRST_FAILED(handle))
695 _splitpath(filename, drive, dir, fname, ext);
697 gfilename = (char *) ecalloc(len, sizeof(char));
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);
705 if (qfilename != NULL)
707 n = (int) strlen(qfilename);
708 while (p - gfilename + n + 2 >= len)
711 * No room in current buffer.
712 * Allocate a bigger one.
716 p = (char *) ecalloc(len, sizeof(char));
717 strcpy(p, gfilename);
720 p = gfilename + strlen(gfilename);
722 strcpy(p, qfilename);
727 } while (GLOB_NEXT_NAME(handle, &fnd) == 0);
730 * Overwrite the final trailing space with a null terminator.
733 GLOB_NAME_DONE(handle);
739 * We get the shell to glob the filename for us by passing
740 * an "echo" command to the shell and reading its output.
749 esc = get_meta_escape();
750 if (strlen(esc) == 0)
752 esc = shell_quote(esc);
757 lessecho = lgetenv("LESSECHO");
758 if (isnullenv(lessecho))
759 lessecho = "lessecho";
761 * Invoke lessecho, and read its output (a globbed list of filenames).
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);
767 for (s = metachars(); *s != '\0'; s++)
768 sprintf(cmd + strlen(cmd), "-n0x%x ", *s);
769 sprintf(cmd + strlen(cmd), "-- %s", filename);
775 * Cannot create the pipe.
776 * Just return the original (fexpanded) filename.
780 gfilename = readfd(fd);
782 if (*gfilename == '\0')
790 * No globbing functions at all. Just use the fexpanded filename.
792 gfilename = save(filename);
801 * Return canonical pathname.
808 char rpath[PATH_MAX];
809 if (realpath(path, rpath) != NULL)
810 return (save(rpath));
816 * Return number of %s escapes in a string.
817 * Return a large number if there are any other % escapes besides %s.
825 while (*lessopen != '\0')
827 if (*lessopen == '%')
829 if (lessopen[1] == '%')
831 else if (lessopen[1] == 's')
842 * See if we should open a "replacement file"
843 * instead of the file we're about to open.
846 open_altfile(filename, pf, pfd)
863 if (!use_lessopen || secure)
866 if ((lessopen = lgetenv("LESSOPEN")) == NULL)
868 while (*lessopen == '|')
871 * If LESSOPEN starts with a |, it indicates
872 * a "pipe preprocessor".
875 error("LESSOPEN pipe is not supported", NULL_PARG);
882 if (*lessopen == '-')
885 * Lessopen preprocessor will accept "-" as a filename.
890 if (strcmp(filename, "-") == 0)
893 if (num_pct_s(lessopen) != 1)
895 error("LESSOPEN ignored: must contain exactly one %%s", NULL_PARG);
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);
909 * Cannot create the pipe.
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.
926 if (read(f, &c, 1) != 1)
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.
935 int status = pclose(fd);
936 if (returnfd > 1 && status == 0) {
940 return (save(FAKE_EMPTYFILE));
945 /* Alt pipe contains data, so use it. */
952 /* The alt file is a regular file. Read its name from LESSOPEN. */
957 * Pipe is empty. This means there is no alt file.
961 #endif /* HAVE_POPEN */
965 * Close a replacement file.
968 close_altfile(altfilename, filename)
981 if ((lessclose = lgetenv("LESSCLOSE")) == NULL)
983 if (num_pct_s(lessclose) > 2)
985 error("LESSCLOSE ignored; must contain no more than 2 %%s", NULL_PARG);
988 len = (int) (strlen(lessclose) + strlen(filename) + strlen(altfilename) + 2);
989 cmd = (char *) ecalloc(len, sizeof(char));
990 SNPRINTF2(cmd, len, lessclose, filename, altfilename);
999 * Is the specified file a directory?
1010 struct stat statbuf;
1012 r = stat(filename, &statbuf);
1013 isdir = (r >= 0 && S_ISDIR(statbuf.st_mode));
1020 f = open(filename, S_IREAD | S_IFDIR);
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.)
1041 if (!force_open && is_dir(filename))
1043 static char is_a_dir[] = " is a directory";
1045 m = (char *) ecalloc(strlen(filename) + sizeof(is_a_dir),
1047 strcpy(m, filename);
1048 strcat(m, is_a_dir);
1053 struct stat statbuf;
1055 r = stat(filename, &statbuf);
1058 m = errno_message(filename);
1059 } else if (force_open)
1062 } else if (!S_ISREG(statbuf.st_mode))
1064 static char not_reg[] = " is not a regular file (use -f to see it)";
1065 m = (char *) ecalloc(strlen(filename) + sizeof(not_reg),
1067 strcpy(m, filename);
1076 * Return the size of a file, as cheaply as possible.
1077 * In Unix, we can stat the file.
1084 struct stat statbuf;
1086 if (fstat(f, &statbuf) >= 0)
1087 return ((POSITION) statbuf.st_size);
1092 if ((size = (long) _gs_size(f)) >= 0)
1093 return ((POSITION) size);
1096 return (seek_filesize(f));
1103 shell_coption(VOID_PARAM)
1109 * Return last component of a pathname.
1112 last_component(name)
1117 for (slash = name + strlen(name); slash > name; )
1120 if (*slash == *PATHNAME_SEP || *slash == '/')