1 /* expand - convert tabs to spaces
2 Copyright (C) 89, 91, 1995-2003 Free Software Foundation, Inc.
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
18 /* By default, convert all tabs to spaces.
19 Preserves backspace characters in the output; they decrement the
20 column count for tab calculations.
21 The default action is equivalent to -8.
24 --tabs=tab1[,tab2[,...]]
26 -tab1[,tab2[,...]] If only one tab stop is given, set the tabs tab1
27 spaces apart instead of the default 8. Otherwise,
28 set the tabs at columns tab1, tab2, etc. (numbered from
29 0); replace any tabs beyond the tabstops given with
32 -i Only convert initial tabs on each line to spaces.
34 David MacKenzie <djm@gnu.ai.mit.edu> */
40 #include <sys/types.h>
48 /* The official name of this program (e.g., no `g' prefix). */
49 #define PROGRAM_NAME "expand"
51 #define AUTHORS "David MacKenzie"
53 /* The number of bytes added at a time to the amount of memory
54 allocated for the output line. */
55 #define OUTPUT_BLOCK 256
57 /* The number of bytes added at a time to the amount of memory
58 allocated for the list of tabstops. */
59 #define TABLIST_BLOCK 256
61 /* The name this program was run with. */
64 /* If nonzero, convert blanks even after nonblank characters have been
66 static int convert_entire_line;
68 /* If nonzero, the size of all tab stops. If zero, use `tab_list' instead. */
71 /* Array of the explicit column numbers of the tab stops;
72 after `tab_list' is exhausted, each additional tab is replaced
73 by a space. The first column is column 0. */
76 /* The index of the first invalid element of `tab_list',
77 where the next element can be added. */
78 static int first_free_tab;
80 /* Null-terminated array of input filenames. */
81 static char **file_list;
83 /* Default for `file_list' if no files are given on the command line. */
84 static char *stdin_argv[] =
89 /* Nonzero if we have ever read standard input. */
90 static int have_read_stdin;
92 /* Status to return to the system. */
93 static int exit_status;
95 static struct option const longopts[] =
97 {"tabs", required_argument, NULL, 't'},
98 {"initial", no_argument, NULL, 'i'},
99 {GETOPT_HELP_OPTION_DECL},
100 {GETOPT_VERSION_OPTION_DECL},
108 fprintf (stderr, _("Try `%s --help' for more information.\n"),
113 Usage: %s [OPTION]... [FILE]...\n\
117 Convert tabs in each FILE to spaces, writing to standard output.\n\
118 With no FILE, or when FILE is -, read standard input.\n\
122 Mandatory arguments to long options are mandatory for short options too.\n\
125 -i, --initial do not convert TABs after non whitespace\n\
126 -t, --tabs=NUMBER have tabs NUMBER characters apart, not 8\n\
129 -t, --tabs=LIST use comma separated list of explicit tab positions\n\
131 fputs (HELP_OPTION_DESCRIPTION, stdout);
132 fputs (VERSION_OPTION_DESCRIPTION, stdout);
133 printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
135 exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
138 /* Add tab stop TABVAL to the end of `tab_list', except
139 if TABVAL is -1, do nothing. */
142 add_tabstop (int tabval)
146 if (first_free_tab % TABLIST_BLOCK == 0)
147 tab_list = xrealloc (tab_list, (first_free_tab
148 + TABLIST_BLOCK * sizeof (tab_list[0])));
149 tab_list[first_free_tab++] = tabval;
152 /* Add the comma or blank separated list of tabstops STOPS
153 to the list of tabstops. */
156 parse_tabstops (char const *stops)
159 char const *num_start IF_LINT (= NULL);
162 for (; *stops; stops++)
164 if (*stops == ',' || ISBLANK (*stops))
166 add_tabstop (tabval);
169 else if (ISDIGIT (*stops))
177 /* Detect overflow. */
179 tabval = tabval * 10 + *stops - '0';
182 size_t len = strspn (num_start, "0123456789");
183 char *bad_num = xstrndup (num_start, len);
184 error (0, 0, _("tab stop is too large %s"), quote (bad_num));
186 stops = num_start + len - 1;
192 error (0, 0, _("tab size contains invalid character(s): %s"),
202 add_tabstop (tabval);
205 /* Check that the list of tabstops TABS, with ENTRIES entries,
206 contains only nonzero, ascending values. */
209 validate_tabstops (int *tabs, int entries)
214 for (i = 0; i < entries; i++)
217 error (EXIT_FAILURE, 0, _("tab size cannot be 0"));
218 if (tabs[i] <= prev_tab)
219 error (EXIT_FAILURE, 0, _("tab sizes must be ascending"));
224 /* Close the old stream pointer FP if it is non-NULL,
225 and return a new one opened to read the next input file.
226 Open a filename of `-' as the standard input.
227 Return NULL if there are no more input files. */
232 static char *prev_file;
239 error (0, errno, "%s", prev_file);
243 clearerr (fp); /* Also clear EOF. */
244 else if (fclose (fp) == EOF)
246 error (0, errno, "%s", prev_file);
251 while ((file = *file_list++) != NULL)
253 if (file[0] == '-' && file[1] == '\0')
259 fp = fopen (file, "r");
265 error (0, errno, "%s", file);
271 /* Change tabs to spaces, writing to stdout.
272 Read each file in `file_list', in order. */
277 FILE *fp; /* Input stream. */
278 int c; /* Each input character. */
279 int tab_index = 0; /* Index in `tab_list' of next tabstop. */
280 int column = 0; /* Column on screen of the next char. */
281 int next_tab_column; /* Column the next tab stop is on. */
282 int convert = 1; /* If nonzero, perform translations. */
284 fp = next_file ((FILE *) NULL);
288 /* Binary I/O will preserve the original EOL style (DOS/Unix) of files. */
289 SET_BINARY2 (fileno (fp), STDOUT_FILENO);
298 break; /* No more files. */
301 SET_BINARY2 (fileno (fp), STDOUT_FILENO);
313 else if (c == '\t' && convert)
317 /* Do not let tab_index == first_free_tab;
318 stop when it is 1 less. */
319 while (tab_index < first_free_tab - 1
320 && column >= tab_list[tab_index])
322 next_tab_column = tab_list[tab_index];
323 if (tab_index < first_free_tab - 1)
325 if (column >= next_tab_column)
326 next_tab_column = column + 1; /* Ran out of tab stops. */
330 next_tab_column = column + tab_size - column % tab_size;
332 while (column < next_tab_column)
350 if (convert_entire_line == 0)
360 main (int argc, char **argv)
362 int tabval = -1; /* Value of tabstop being read, or -1. */
363 int c; /* Option character. */
365 bool obsolete_tablist = false;
369 convert_entire_line = 1;
372 initialize_main (&argc, &argv);
373 program_name = argv[0];
374 setlocale (LC_ALL, "");
375 bindtextdomain (PACKAGE, LOCALEDIR);
376 textdomain (PACKAGE);
378 atexit (close_stdout);
380 while ((c = getopt_long (argc, argv, "it:,0123456789", longopts, NULL)) != -1)
388 usage (EXIT_FAILURE);
390 convert_entire_line = 0;
393 parse_tabstops (optarg);
396 add_tabstop (tabval);
398 obsolete_tablist = true;
400 case_GETOPT_HELP_CHAR;
401 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
405 tabval = tabval * 10 + c - '0';
406 obsolete_tablist = true;
411 if (obsolete_tablist && 200112 <= posix2_version ())
413 error (0, 0, _("`-LIST' option is obsolete; use `-t LIST'"));
414 usage (EXIT_FAILURE);
417 add_tabstop (tabval);
419 validate_tabstops (tab_list, first_free_tab);
421 if (first_free_tab == 0)
423 else if (first_free_tab == 1)
424 tab_size = tab_list[0];
428 file_list = (optind < argc ? &argv[optind] : stdin_argv);
432 if (have_read_stdin && fclose (stdin) == EOF)
433 error (EXIT_FAILURE, errno, "-");
435 exit (exit_status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);