diff options
Diffstat (limited to 'coreutils/fold.c')
| -rw-r--r-- | coreutils/fold.c | 202 |
1 files changed, 202 insertions, 0 deletions
diff --git a/coreutils/fold.c b/coreutils/fold.c new file mode 100644 index 0000000..f9ae526 --- /dev/null +++ b/coreutils/fold.c @@ -0,0 +1,202 @@ +/* fold -- wrap each input line to fit in specified width. + + Written by David MacKenzie, djm@gnu.ai.mit.edu. + Copyright (C) 91, 1995-2002 Free Software Foundation, Inc. + + Modified for busybox based on coreutils v 5.0 + Copyright (C) 2003 Glenn McGrath <bug1@optushome.com.au> + + 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. +*/ + +#include <ctype.h> +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <getopt.h> +#include <sys/types.h> + +#include "busybox.h" + +/* If nonzero, count bytes, not column positions. */ +static int count_bytes; + +/* 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; +} + +extern int fold_main(int argc, char **argv) +{ + /* If nonzero, try to break on whitespace. */ + int break_spaces; + + /* If nonzero, at least one of the files we read was standard input. */ + int have_read_stdin; + + int width = 80; + int i; + int optc; + int errs = 0; + + break_spaces = count_bytes = have_read_stdin = 0; + + /* Turn any numeric options into -w options. */ + for (i = 1; i < argc; i++) { + char const *a = argv[i]; + + if (a[0] == '-') { + if (a[1] == '-' && !a[2]) + break; + if (isdigit(a[1])) { + char *s = xmalloc(strlen(a) + 2); + + s[0] = '-'; + s[1] = 'w'; + strcpy(s + 2, a + 1); + argv[i] = s; + } + } + } + + while ((optc = getopt(argc, argv, "bsw:")) > 0) { + switch (optc) { + 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. */ + long int tmp_long; + char *end_ptr; + + errno = 0; + tmp_long = strtol(optarg, &end_ptr, 10); + if (!end_ptr || errno || tmp_long < 1) { + bb_error_msg_and_die("invalid number of columns: `%s'", optarg); + } + width = (int) tmp_long; + break; + } + default: + bb_show_usage(); + } + } + + argv += optind; + if (!*argv) { + *--argv = "-"; + } + + do { + FILE *istream = bb_wfopen_input(*argv); + if (istream != NULL) { + int c; + int column = 0; /* Screen column where next char will go. */ + int offset_out = 0; /* Index in `line_out' for next char. */ + static char *line_out = NULL; + static int allocated_out = 0; + + 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), (size_t) 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) { + /* Found a blank. Don't output the part after it. */ + logical_end++; + fwrite(line_out, sizeof(char), (size_t) 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), (size_t) offset_out, stdout); + column = offset_out = 0; + goto rescan; + } + + line_out[offset_out++] = c; + } + + if (offset_out) { + fwrite(line_out, sizeof(char), (size_t) offset_out, stdout); + } + + if (ferror(istream) || bb_fclose_nonstdin(istream)) { + bb_perror_msg("%s", *argv); /* Avoid multibyte problems. */ + errs |= EXIT_FAILURE; + } + } else { + errs |= EXIT_FAILURE; + } + } while (*++argv); + + bb_fflush_stdout_and_exit(errs); +} |