/* fold -- wrap each input line to fit in specified width. Copyright (C) 1991, 1995 Free Software Foundation, Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Written by David MacKenzie, djm@gnu.ai.mit.edu. */ #include /* Get isblank from GNU libc. */ #define _GNU_SOURCE #include #include #include #include "system.h" #include "version.h" #include "error.h" char *xrealloc (); char *xmalloc (); /* The name this program was run with. */ char *program_name; /* If nonzero, try to break on whitespace. */ static int break_spaces; /* If nonzero, count bytes, not column positions. */ static int count_bytes; /* If nonzero, at least one of the files we read was standard input. */ static int have_read_stdin; /* If non-zero, display usage information and exit. */ static int show_help; /* If non-zero, print the version on standard output then exit. */ static int show_version; static struct option const longopts[] = { {"bytes", no_argument, NULL, 'b'}, {"spaces", no_argument, NULL, 's'}, {"width", required_argument, NULL, 'w'}, {"help", no_argument, &show_help, 1}, {"version", no_argument, &show_version, 1}, {NULL, 0, NULL, 0} }; static void usage (int status) { if (status != 0) fprintf (stderr, _("Try `%s --help' for more information.\n"), program_name); else { printf (_("\ Usage: %s [OPTION]... [FILE]...\n\ "), program_name); printf (_("\ Wrap input lines in each FILE (standard input by default), writing to\n\ standard output.\n\ \n\ -b, --bytes count bytes rather than columns\n\ -s, --spaces break at word boundaries\n\ -w, --width=WIDTH use WIDTH columns instead of 80\n\ ")); } exit (status); } /* Assuming the current column is COLUMN, return the column that printing C will move the cursor to. The first column is 0. */ static int adjust_column (int column, char c) { if (!count_bytes) { if (c == '\b') { if (column > 0) column--; } else if (c == '\r') column = 0; else if (c == '\t') column = column + 8 - column % 8; else /* if (isprint (c)) */ column++; } else column++; return column; } /* Fold file FILENAME, or standard input if FILENAME is "-", to stdout, with maximum line length WIDTH. Return 0 if successful, 1 if an error occurs. */ static int fold_file (char *filename, int width) { FILE *istream; register int c; int column = 0; /* Screen column where next char will go. */ size_t offset_out = 0; /* Index in `line_out' for next char. */ static char *line_out = NULL; static size_t allocated_out = 0; if (!strcmp (filename, "-")) { istream = stdin; have_read_stdin = 1; } else istream = fopen (filename, "r"); if (istream == NULL) { error (0, errno, "%s", filename); return 1; } while ((c = getc (istream)) != EOF) { if (offset_out + 1 >= allocated_out) { allocated_out += 1024; line_out = xrealloc (line_out, allocated_out); } if (c == '\n') { line_out[offset_out++] = c; fwrite (line_out, sizeof (char), offset_out, stdout); column = offset_out = 0; continue; } rescan: column = adjust_column (column, c); if (column > width) { /* This character would make the line too long. Print the line plus a newline, and make this character start the next line. */ if (break_spaces) { /* Look for the last blank. */ int logical_end; for (logical_end = offset_out - 1; logical_end >= 0; logical_end--) if (ISBLANK (line_out[logical_end])) break; if (logical_end >= 0) { int i; /* Found a blank. Don't output the part after it. */ logical_end++; fwrite (line_out, sizeof (char), logical_end, stdout); putchar ('\n'); /* Move the remainder to the beginning of the next line. The areas being copied here might overlap. */ memmove (line_out, line_out + logical_end, offset_out - logical_end); offset_out -= logical_end; for (column = i = 0; i < offset_out; i++) column = adjust_column (column, line_out[i]); goto rescan; } } else { if (offset_out == 0) { line_out[offset_out++] = c; continue; } } line_out[offset_out++] = '\n'; fwrite (line_out, sizeof (char), offset_out, stdout); column = offset_out = 0; goto rescan; } line_out[offset_out++] = c; } if (offset_out) fwrite (line_out, sizeof (char), offset_out, stdout); if (ferror (istream)) { error (0, errno, "%s", filename); if (strcmp (filename, "-")) fclose (istream); return 1; } if (strcmp (filename, "-") && fclose (istream) == EOF) { error (0, errno, "%s", filename); return 1; } if (ferror (stdout)) { error (0, errno, _("write error")); return 1; } return 0; } void main (int argc, char **argv) { int width = 80; int i; int optc; int errs = 0; program_name = argv[0]; break_spaces = count_bytes = have_read_stdin = 0; /* Turn any numeric options into -w options. */ for (i = 1; i < argc; i++) { if (argv[i][0] == '-' && ISDIGIT (argv[i][1])) { char *s; s = xmalloc (strlen (argv[i]) + 2); s[0] = '-'; s[1] = 'w'; strcpy (s + 2, argv[i] + 1); argv[i] = s; } } while ((optc = getopt_long (argc, argv, "bsw:", longopts, (int *) 0)) != EOF) { switch (optc) { case 0: break; case 'b': /* Count bytes rather than columns. */ count_bytes = 1; break; case 's': /* Break at word boundaries. */ break_spaces = 1; break; case 'w': /* Line width. */ width = atoi (optarg); if (width < 1) error (1, 0, _("%s: invalid line width"), optarg); break; default: usage (1); } } if (show_version) { printf ("fold - %s\n", version_string); exit (0); } if (show_help) usage (0); if (argc == optind) errs |= fold_file ("-", width); else for (i = optind; i < argc; i++) errs |= fold_file (argv[i], width); if (have_read_stdin && fclose (stdin) == EOF) error (1, errno, "-"); if (fclose (stdout) == EOF) error (1, errno, _("write error")); exit (errs); }