1 /* fold -- wrap each input line to fit in specified width.
2 Copyright (C) 91, 1995-2000 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 /* Written by David MacKenzie, djm@gnu.ai.mit.edu. */
24 #include <sys/types.h>
31 /* The official name of this program (e.g., no `g' prefix). */
32 #define PROGRAM_NAME "fold"
34 #define AUTHORS "David MacKenzie"
36 /* The name this program was run with. */
39 /* If nonzero, try to break on whitespace. */
40 static int break_spaces;
42 /* If nonzero, count bytes, not column positions. */
43 static int count_bytes;
45 /* If nonzero, at least one of the files we read was standard input. */
46 static int have_read_stdin;
48 static struct option const longopts[] =
50 {"bytes", no_argument, NULL, 'b'},
51 {"spaces", no_argument, NULL, 's'},
52 {"width", required_argument, NULL, 'w'},
53 {GETOPT_HELP_OPTION_DECL},
54 {GETOPT_VERSION_OPTION_DECL},
62 fprintf (stderr, _("Try `%s --help' for more information.\n"),
67 Usage: %s [OPTION]... [FILE]...\n\
71 Wrap input lines in each FILE (standard input by default), writing to\n\
74 -b, --bytes count bytes rather than columns\n\
75 -s, --spaces break at spaces\n\
76 -w, --width=WIDTH use WIDTH columns instead of 80\n\
77 --help display this help and exit\n\
78 --version output version information and exit\n\
80 puts (_("\nReport bugs to <bug-textutils@gnu.org>."));
82 exit (status == 0 ? EXIT_SUCCESS : EXIT_FAILURE);
85 /* Assuming the current column is COLUMN, return the column that
86 printing C will move the cursor to.
87 The first column is 0. */
90 adjust_column (int column, char c)
102 column = column + 8 - column % 8;
103 else /* if (isprint (c)) */
111 /* Fold file FILENAME, or standard input if FILENAME is "-",
112 to stdout, with maximum line length WIDTH.
113 Return 0 if successful, 1 if an error occurs. */
116 fold_file (char *filename, int width)
120 int column = 0; /* Screen column where next char will go. */
121 int offset_out = 0; /* Index in `line_out' for next char. */
122 static char *line_out = NULL;
123 static int allocated_out = 0;
125 if (STREQ (filename, "-"))
131 istream = fopen (filename, "r");
135 error (0, errno, "%s", filename);
139 while ((c = getc (istream)) != EOF)
141 if (offset_out + 1 >= allocated_out)
143 allocated_out += 1024;
144 line_out = xrealloc (line_out, allocated_out);
149 line_out[offset_out++] = c;
150 fwrite (line_out, sizeof (char), (size_t) offset_out, stdout);
151 column = offset_out = 0;
156 column = adjust_column (column, c);
160 /* This character would make the line too long.
161 Print the line plus a newline, and make this character
162 start the next line. */
165 /* Look for the last blank. */
168 for (logical_end = offset_out - 1; logical_end >= 0;
170 if (ISBLANK (line_out[logical_end]))
172 if (logical_end >= 0)
176 /* Found a blank. Don't output the part after it. */
178 fwrite (line_out, sizeof (char), (size_t) logical_end,
181 /* Move the remainder to the beginning of the next line.
182 The areas being copied here might overlap. */
183 memmove (line_out, line_out + logical_end,
184 offset_out - logical_end);
185 offset_out -= logical_end;
186 for (column = i = 0; i < offset_out; i++)
187 column = adjust_column (column, line_out[i]);
195 line_out[offset_out++] = c;
199 line_out[offset_out++] = '\n';
200 fwrite (line_out, sizeof (char), (size_t) offset_out, stdout);
201 column = offset_out = 0;
205 line_out[offset_out++] = c;
209 fwrite (line_out, sizeof (char), (size_t) offset_out, stdout);
211 if (ferror (istream))
213 error (0, errno, "%s", filename);
214 if (!STREQ (filename, "-"))
218 if (!STREQ (filename, "-") && fclose (istream) == EOF)
220 error (0, errno, "%s", filename);
228 main (int argc, char **argv)
235 program_name = argv[0];
236 setlocale (LC_ALL, "");
237 bindtextdomain (PACKAGE, LOCALEDIR);
238 textdomain (PACKAGE);
240 atexit (close_stdout);
242 break_spaces = count_bytes = have_read_stdin = 0;
244 /* Turn any numeric options into -w options. */
245 for (i = 1; i < argc; i++)
247 if (argv[i][0] == '-' && ISDIGIT (argv[i][1]))
251 s = xmalloc (strlen (argv[i]) + 2);
254 strcpy (s + 2, argv[i] + 1);
259 while ((optc = getopt_long (argc, argv, "bsw:", longopts, NULL)) != -1)
266 case 'b': /* Count bytes rather than columns. */
270 case 's': /* Break at word boundaries. */
274 case 'w': /* Line width. */
277 if (xstrtol (optarg, NULL, 10, &tmp_long, "") != LONGINT_OK
278 || tmp_long <= 0 || tmp_long > INT_MAX)
279 error (EXIT_FAILURE, 0,
280 _("invalid number of columns: `%s'"), optarg);
281 width = (int) tmp_long;
285 case_GETOPT_HELP_CHAR;
287 case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
295 errs |= fold_file ("-", width);
297 for (i = optind; i < argc; i++)
298 errs |= fold_file (argv[i], width);
300 if (have_read_stdin && fclose (stdin) == EOF)
301 error (EXIT_FAILURE, errno, "-");
303 exit (errs == 0 ? EXIT_SUCCESS : EXIT_FAILURE);