1 /* expand - convert tabs to spaces
2 Copyright (C) 89, 91, 95, 96, 1997 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> */
38 /* Get isblank from GNU libc. */
43 #include <sys/types.h>
47 /* The number of bytes added at a time to the amount of memory
48 allocated for the output line. */
49 #define OUTPUT_BLOCK 256
51 /* The number of bytes added at a time to the amount of memory
52 allocated for the list of tabstops. */
53 #define TABLIST_BLOCK 256
55 /* The name this program was run with. */
58 /* If nonzero, convert blanks even after nonblank characters have been
60 static int convert_entire_line;
62 /* If nonzero, the size of all tab stops. If zero, use `tab_list' instead. */
65 /* Array of the explicit column numbers of the tab stops;
66 after `tab_list' is exhausted, each additional tab is replaced
67 by a space. The first column is column 0. */
70 /* The index of the first invalid element of `tab_list',
71 where the next element can be added. */
72 static int first_free_tab;
74 /* Null-terminated array of input filenames. */
75 static char **file_list;
77 /* Default for `file_list' if no files are given on the command line. */
78 static char *stdin_argv[] =
83 /* Nonzero if we have ever read standard input. */
84 static int have_read_stdin;
86 /* Status to return to the system. */
87 static int exit_status;
89 /* If nonzero, display usage information and exit. */
92 /* If nonzero, print the version on standard output then exit. */
93 static int show_version;
95 static struct option const longopts[] =
97 {"tabs", required_argument, NULL, 't'},
98 {"initial", no_argument, NULL, 'i'},
99 {"help", no_argument, &show_help, 1},
100 {"version", no_argument, &show_version, 1},
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\
120 -i, --initial do not convert TABs after non whitespace\n\
121 -t, --tabs=NUMBER have tabs NUMBER characters apart, not 8\n\
122 -t, --tabs=LIST use comma separated list of explicit tab positions\n\
123 --help display this help and exit\n\
124 --version output version information and exit\n\
126 Instead of -t NUMBER or -t LIST, -NUMBER or -LIST may be used.\n\
128 puts (_("\nReport bugs to <textutils-bugs@gnu.org>."));
130 exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
133 /* Add tab stop TABVAL to the end of `tab_list', except
134 if TABVAL is -1, do nothing. */
137 add_tabstop (int tabval)
141 if (first_free_tab % TABLIST_BLOCK == 0)
142 tab_list = (int *) xrealloc ((char *) tab_list,
144 + TABLIST_BLOCK * sizeof (tab_list[0])));
145 tab_list[first_free_tab++] = tabval;
148 /* Add the comma or blank separated list of tabstops STOPS
149 to the list of tabstops. */
152 parse_tabstops (char *stops)
156 for (; *stops; stops++)
158 if (*stops == ',' || ISBLANK (*stops))
160 add_tabstop (tabval);
163 else if (ISDIGIT (*stops))
167 tabval = tabval * 10 + *stops - '0';
170 error (EXIT_FAILURE, 0, _("tab size contains an invalid character"));
173 add_tabstop (tabval);
176 /* Check that the list of tabstops TABS, with ENTRIES entries,
177 contains only nonzero, ascending values. */
180 validate_tabstops (int *tabs, int entries)
185 for (i = 0; i < entries; i++)
188 error (EXIT_FAILURE, 0, _("tab size cannot be 0"));
189 if (tabs[i] <= prev_tab)
190 error (EXIT_FAILURE, 0, _("tab sizes must be ascending"));
195 /* Close the old stream pointer FP if it is non-NULL,
196 and return a new one opened to read the next input file.
197 Open a filename of `-' as the standard input.
198 Return NULL if there are no more input files. */
203 static char *prev_file;
210 error (0, errno, "%s", prev_file);
214 clearerr (fp); /* Also clear EOF. */
215 else if (fclose (fp) == EOF)
217 error (0, errno, "%s", prev_file);
222 while ((file = *file_list++) != NULL)
224 if (file[0] == '-' && file[1] == '\0')
230 fp = fopen (file, "r");
236 error (0, errno, "%s", file);
242 /* Change tabs to spaces, writing to stdout.
243 Read each file in `file_list', in order. */
248 FILE *fp; /* Input stream. */
249 int c; /* Each input character. */
250 int tab_index = 0; /* Index in `tab_list' of next tabstop. */
251 int column = 0; /* Column on screen of the next char. */
252 int next_tab_column; /* Column the next tab stop is on. */
253 int convert = 1; /* If nonzero, perform translations. */
255 fp = next_file ((FILE *) NULL);
265 break; /* No more files. */
277 else if (c == '\t' && convert)
281 /* Do not let tab_index == first_free_tab;
282 stop when it is 1 less. */
283 while (tab_index < first_free_tab - 1
284 && column >= tab_list[tab_index])
286 next_tab_column = tab_list[tab_index];
287 if (tab_index < first_free_tab - 1)
289 if (column >= next_tab_column)
290 next_tab_column = column + 1; /* Ran out of tab stops. */
294 next_tab_column = column + tab_size - column % tab_size;
296 while (column < next_tab_column)
314 if (convert_entire_line == 0)
324 main (int argc, char **argv)
326 int tabval = -1; /* Value of tabstop being read, or -1. */
327 int c; /* Option character. */
331 convert_entire_line = 1;
334 program_name = argv[0];
335 setlocale (LC_ALL, "");
336 bindtextdomain (PACKAGE, LOCALEDIR);
337 textdomain (PACKAGE);
339 while ((c = getopt_long (argc, argv, "it:,0123456789", longopts, NULL)) != -1)
349 convert_entire_line = 0;
352 parse_tabstops (optarg);
355 add_tabstop (tabval);
361 tabval = tabval * 10 + c - '0';
368 printf ("expand (%s) %s\n", GNU_PACKAGE, VERSION);
375 add_tabstop (tabval);
377 validate_tabstops (tab_list, first_free_tab);
379 if (first_free_tab == 0)
381 else if (first_free_tab == 1)
382 tab_size = tab_list[0];
387 file_list = stdin_argv;
389 file_list = &argv[optind];
393 if (have_read_stdin && fclose (stdin) == EOF)
394 error (EXIT_FAILURE, errno, "-");
395 if (ferror (stdout) || fclose (stdout) == EOF)
396 error (EXIT_FAILURE, errno, _("write error"));
398 exit (exit_status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);