1 /* expand - convert tabs to spaces
2 Copyright (C) 89, 91, 95, 96, 1997, 1998 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>
44 /* The number of bytes added at a time to the amount of memory
45 allocated for the output line. */
46 #define OUTPUT_BLOCK 256
48 /* The number of bytes added at a time to the amount of memory
49 allocated for the list of tabstops. */
50 #define TABLIST_BLOCK 256
52 /* The name this program was run with. */
55 /* If nonzero, convert blanks even after nonblank characters have been
57 static int convert_entire_line;
59 /* If nonzero, the size of all tab stops. If zero, use `tab_list' instead. */
62 /* Array of the explicit column numbers of the tab stops;
63 after `tab_list' is exhausted, each additional tab is replaced
64 by a space. The first column is column 0. */
67 /* The index of the first invalid element of `tab_list',
68 where the next element can be added. */
69 static int first_free_tab;
71 /* Null-terminated array of input filenames. */
72 static char **file_list;
74 /* Default for `file_list' if no files are given on the command line. */
75 static char *stdin_argv[] =
80 /* Nonzero if we have ever read standard input. */
81 static int have_read_stdin;
83 /* Status to return to the system. */
84 static int exit_status;
86 /* If nonzero, display usage information and exit. */
89 /* If nonzero, print the version on standard output then exit. */
90 static int show_version;
92 static struct option const longopts[] =
94 {"tabs", required_argument, NULL, 't'},
95 {"initial", no_argument, NULL, 'i'},
96 {"help", no_argument, &show_help, 1},
97 {"version", no_argument, &show_version, 1},
105 fprintf (stderr, _("Try `%s --help' for more information.\n"),
110 Usage: %s [OPTION]... [FILE]...\n\
114 Convert tabs in each FILE to spaces, writing to standard output.\n\
115 With no FILE, or when FILE is -, read standard input.\n\
117 -i, --initial do not convert TABs after non whitespace\n\
118 -t, --tabs=NUMBER have tabs NUMBER characters apart, not 8\n\
119 -t, --tabs=LIST use comma separated list of explicit tab positions\n\
120 --help display this help and exit\n\
121 --version output version information and exit\n\
123 Instead of -t NUMBER or -t LIST, -NUMBER or -LIST may be used.\n\
125 puts (_("\nReport bugs to <bug-textutils@gnu.org>."));
127 exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
130 /* Add tab stop TABVAL to the end of `tab_list', except
131 if TABVAL is -1, do nothing. */
134 add_tabstop (int tabval)
138 if (first_free_tab % TABLIST_BLOCK == 0)
139 tab_list = (int *) xrealloc ((char *) tab_list,
141 + TABLIST_BLOCK * sizeof (tab_list[0])));
142 tab_list[first_free_tab++] = tabval;
145 /* Add the comma or blank separated list of tabstops STOPS
146 to the list of tabstops. */
149 parse_tabstops (char *stops)
153 for (; *stops; stops++)
155 if (*stops == ',' || ISBLANK (*stops))
157 add_tabstop (tabval);
160 else if (ISDIGIT (*stops))
164 tabval = tabval * 10 + *stops - '0';
167 error (EXIT_FAILURE, 0, _("tab size contains an invalid character"));
170 add_tabstop (tabval);
173 /* Check that the list of tabstops TABS, with ENTRIES entries,
174 contains only nonzero, ascending values. */
177 validate_tabstops (int *tabs, int entries)
182 for (i = 0; i < entries; i++)
185 error (EXIT_FAILURE, 0, _("tab size cannot be 0"));
186 if (tabs[i] <= prev_tab)
187 error (EXIT_FAILURE, 0, _("tab sizes must be ascending"));
192 /* Close the old stream pointer FP if it is non-NULL,
193 and return a new one opened to read the next input file.
194 Open a filename of `-' as the standard input.
195 Return NULL if there are no more input files. */
200 static char *prev_file;
207 error (0, errno, "%s", prev_file);
211 clearerr (fp); /* Also clear EOF. */
212 else if (fclose (fp) == EOF)
214 error (0, errno, "%s", prev_file);
219 while ((file = *file_list++) != NULL)
221 if (file[0] == '-' && file[1] == '\0')
227 fp = fopen (file, "r");
233 error (0, errno, "%s", file);
239 /* Change tabs to spaces, writing to stdout.
240 Read each file in `file_list', in order. */
245 FILE *fp; /* Input stream. */
246 int c; /* Each input character. */
247 int tab_index = 0; /* Index in `tab_list' of next tabstop. */
248 int column = 0; /* Column on screen of the next char. */
249 int next_tab_column; /* Column the next tab stop is on. */
250 int convert = 1; /* If nonzero, perform translations. */
252 fp = next_file ((FILE *) NULL);
262 break; /* No more files. */
274 else if (c == '\t' && convert)
278 /* Do not let tab_index == first_free_tab;
279 stop when it is 1 less. */
280 while (tab_index < first_free_tab - 1
281 && column >= tab_list[tab_index])
283 next_tab_column = tab_list[tab_index];
284 if (tab_index < first_free_tab - 1)
286 if (column >= next_tab_column)
287 next_tab_column = column + 1; /* Ran out of tab stops. */
291 next_tab_column = column + tab_size - column % tab_size;
293 while (column < next_tab_column)
311 if (convert_entire_line == 0)
321 main (int argc, char **argv)
323 int tabval = -1; /* Value of tabstop being read, or -1. */
324 int c; /* Option character. */
328 convert_entire_line = 1;
331 program_name = argv[0];
332 setlocale (LC_ALL, "");
333 bindtextdomain (PACKAGE, LOCALEDIR);
334 textdomain (PACKAGE);
336 while ((c = getopt_long (argc, argv, "it:,0123456789", longopts, NULL)) != -1)
346 convert_entire_line = 0;
349 parse_tabstops (optarg);
352 add_tabstop (tabval);
358 tabval = tabval * 10 + c - '0';
365 printf ("expand (%s) %s\n", GNU_PACKAGE, VERSION);
372 add_tabstop (tabval);
374 validate_tabstops (tab_list, first_free_tab);
376 if (first_free_tab == 0)
378 else if (first_free_tab == 1)
379 tab_size = tab_list[0];
384 file_list = stdin_argv;
386 file_list = &argv[optind];
390 if (have_read_stdin && fclose (stdin) == EOF)
391 error (EXIT_FAILURE, errno, "-");
392 if (ferror (stdout) || fclose (stdout) == EOF)
393 error (EXIT_FAILURE, errno, _("write error"));
395 exit (exit_status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);