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ccb8bea4f0
POLA: Changed the default to ``-l 8'' while still providing a way to disable this feature with ``-l 0''. PR: bin/29247 Reviewed by: iedowse
624 lines
22 KiB
C
624 lines
22 KiB
C
/* $OpenBSD: fmt.c,v 1.16 2000/06/25 15:35:42 pjanzen Exp $ */
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/* Sensible version of fmt
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*
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* Syntax: fmt [ options ] [ goal [ max ] ] [ filename ... ]
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*
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* Since the documentation for the original fmt is so poor, here
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* is an accurate description of what this one does. It's usually
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* the same. The *mechanism* used may differ from that suggested
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* here. Note that we are *not* entirely compatible with fmt,
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* because fmt gets so many things wrong.
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*
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* 1. Tabs are expanded, assuming 8-space tab stops.
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* If the `-t <n>' option is given, we assume <n>-space
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* tab stops instead.
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* Trailing blanks are removed from all lines.
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* x\b == nothing, for any x other than \b.
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* Other control characters are simply stripped. This
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* includes \r.
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* 2. Each line is split into leading whitespace and
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* everything else. Maximal consecutive sequences of
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* lines with the same leading whitespace are considered
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* to form paragraphs, except that a blank line is always
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* a paragraph to itself.
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* If the `-p' option is given then the first line of a
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* paragraph is permitted to have indentation different
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* from that of the other lines.
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* If the `-m' option is given then a line that looks
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* like a mail message header, if it is not immediately
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* preceded by a non-blank non-message-header line, is
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* taken to start a new paragraph, which also contains
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* any subsequent lines with non-empty leading whitespace.
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* 3. The "everything else" is split into words; a word
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* includes its trailing whitespace, and a word at the
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* end of a line is deemed to be followed by a single
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* space, or two spaces if it ends with a sentence-end
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* character. (See the `-d' option for how to change that.)
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* If the `-s' option has been given, then a word's trailing
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* whitespace is replaced by what it would have had if it
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* had occurred at end of line.
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* 4. Each paragraph is sent to standard output as follows.
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* We output the leading whitespace, and then enough words
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* to make the line length as near as possible to the goal
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* without exceeding the maximum. (If a single word would
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* exceed the maximum, we output that anyway.) Of course
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* the trailing whitespace of the last word is ignored.
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* We then emit a newline and start again if there are any
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* words left.
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* Note that for a blank line this translates as "We emit
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* a newline".
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* If the `-l <n>' option is given, then leading whitespace
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* is modified slightly: <n> spaces are replaced by a tab.
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* Indented paragraphs (see above under `-p') make matters
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* more complicated than this suggests. Actually every paragraph
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* has two `leading whitespace' values; the value for the first
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* line, and the value for the most recent line. (While processing
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* the first line, the two are equal. When `-p' has not been
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* given, they are always equal.) The leading whitespace
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* actually output is that of the first line (for the first
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* line of *output*) or that of the most recent line (for
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* all other lines of output).
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* When `-m' has been given, message header paragraphs are
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* taken as having first-leading-whitespace empty and
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* subsequent-leading-whitespace two spaces.
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*
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* Multiple input files are formatted one at a time, so that a file
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* never ends in the middle of a line.
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*
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* There's an alternative mode of operation, invoked by giving
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* the `-c' option. In that case we just center every line,
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* and most of the other options are ignored. This should
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* really be in a separate program, but we must stay compatible
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* with old `fmt'.
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*
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* QUERY: Should `-m' also try to do the right thing with quoted text?
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* QUERY: `-b' to treat backslashed whitespace as old `fmt' does?
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* QUERY: Option meaning `never join lines'?
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* QUERY: Option meaning `split in mid-word to avoid overlong lines'?
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* (Those last two might not be useful, since we have `fold'.)
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*
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* Differences from old `fmt':
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*
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* - We have many more options. Options that aren't understood
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* generate a lengthy usage message, rather than being
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* treated as filenames.
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* - Even with `-m', our handling of message headers is
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* significantly different. (And much better.)
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* - We don't treat `\ ' as non-word-breaking.
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* - Downward changes of indentation start new paragraphs
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* for us, as well as upward. (I think old `fmt' behaves
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* in the way it does in order to allow indented paragraphs,
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* but this is a broken way of making indented paragraphs
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* behave right.)
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* - Given the choice of going over or under |goal_length|
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* by the same amount, we go over; old `fmt' goes under.
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* - We treat `?' as ending a sentence, and not `:'. Old `fmt'
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* does the reverse.
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* - We return approved return codes. Old `fmt' returns
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* 1 for some errors, and *the number of unopenable files*
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* when that was all that went wrong.
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* - We have fewer crashes and more helpful error messages.
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* - We don't turn spaces into tabs at starts of lines unless
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* specifically requested.
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* - New `fmt' is somewhat smaller and slightly faster than
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* old `fmt'.
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*
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* Bugs:
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*
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* None known. There probably are some, though.
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*
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* Portability:
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*
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* I believe this code to be pretty portable. It does require
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* that you have `getopt'. If you need to include "getopt.h"
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* for this (e.g., if your system didn't come with `getopt'
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* and you installed it yourself) then you should arrange for
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* NEED_getopt_h to be #defined.
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*
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* Everything here should work OK even on nasty 16-bit
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* machines and nice 64-bit ones. However, it's only really
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* been tested on my FreeBSD machine. Your mileage may vary.
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*/
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/* Copyright (c) 1997 Gareth McCaughan. All rights reserved.
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*
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* Redistribution and use of this code, in source or binary forms,
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* with or without modification, are permitted subject to the following
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* conditions:
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*
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* - Redistribution of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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*
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* - If you distribute modified source code it must also include
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* a notice saying that it has been modified, and giving a brief
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* description of what changes have been made.
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*
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* Disclaimer: I am not responsible for the results of using this code.
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* If it formats your hard disc, sends obscene messages to
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* your boss and kills your children then that's your problem
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* not mine. I give absolutely no warranty of any sort as to
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* what the program will do, and absolutely refuse to be held
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* liable for any consequences of your using it.
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* Thank you. Have a nice day.
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*/
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/* RCS change log:
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* Revision 1.5 1998/03/02 18:02:21 gjm11
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* Minor changes for portability.
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*
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* Revision 1.4 1997/10/01 11:51:28 gjm11
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* Repair broken indented-paragraph handling.
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* Add mail message header stuff.
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* Improve comments and layout.
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* Make usable with non-BSD systems.
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* Add revision display to usage message.
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*
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* Revision 1.3 1997/09/30 16:24:47 gjm11
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* Add copyright notice, rcsid string and log message.
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*
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* Revision 1.2 1997/09/30 16:13:39 gjm11
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* Add options: -d <chars>, -l <width>, -p, -s, -t <width>, -h .
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* Parse options with `getopt'. Clean up code generally.
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* Make comments more accurate.
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*
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* Revision 1.1 1997/09/30 11:29:57 gjm11
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* Initial revision
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*/
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#ifndef lint
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static const char rcsid[] =
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"$FreeBSD$";
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static const char copyright[] =
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"Copyright (c) 1997 Gareth McCaughan. All rights reserved.\n";
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#endif /* not lint */
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#include <ctype.h>
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#include <err.h>
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#include <locale.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sysexits.h>
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#include <unistd.h>
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/* Something that, we hope, will never be a genuine line length,
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* indentation etc.
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*/
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#define SILLY ((size_t)-1)
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/* I used to use |strtoul| for this, but (1) not all systems have it
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* and (2) it's probably better to use |strtol| to detect negative
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* numbers better.
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* If |fussyp==0| then we don't complain about non-numbers
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* (returning 0 instead), but we do complain about bad numbers.
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*/
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static size_t
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get_positive(const char *s, const char *err_mess, int fussyP) {
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char *t;
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long result = strtol(s,&t,0);
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if (*t) { if (fussyP) goto Lose; else return 0; }
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if (result<=0) { Lose: errx(EX_USAGE, "%s", err_mess); }
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return (size_t) result;
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}
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static size_t
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get_nonnegative(const char *s, const char *err_mess, int fussyP) {
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char *t;
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long result = strtol(s,&t,0);
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if (*t) { if (fussyP) goto Lose; else return 0; }
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if (result<0) { Lose: errx(EX_USAGE, "%s", err_mess); }
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return (size_t) result;
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}
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/* Global variables */
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static int centerP=0; /* Try to center lines? */
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static size_t goal_length=0; /* Target length for output lines */
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static size_t max_length=0; /* Maximum length for output lines */
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static int coalesce_spaces_P=0; /* Coalesce multiple whitespace -> ' ' ? */
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static int allow_indented_paragraphs=0; /* Can first line have diff. ind.? */
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static int tab_width=8; /* Number of spaces per tab stop */
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static size_t output_tab_width=8; /* Ditto, when squashing leading spaces */
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static const char *sentence_enders=".?!"; /* Double-space after these */
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static int grok_mail_headers=0; /* treat embedded mail headers magically? */
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static int n_errors=0; /* Number of failed files. Return on exit. */
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static char *output_buffer=0; /* Output line will be built here */
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static size_t x; /* Horizontal position in output line */
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static size_t x0; /* Ditto, ignoring leading whitespace */
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static size_t pending_spaces; /* Spaces to add before next word */
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static int output_in_paragraph=0; /* Any of current para written out yet? */
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/* Prototypes */
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static void process_named_file (const char *);
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static void process_stream (FILE *, const char *);
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static size_t indent_length (const char *, size_t);
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static int might_be_header (const unsigned char *);
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static void new_paragraph (size_t, size_t);
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static void output_word (size_t, size_t, const char *, size_t, size_t);
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static void output_indent (size_t);
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static void center_stream (FILE *, const char *);
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static char * get_line (FILE *, size_t *);
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static void * xrealloc (void *, size_t);
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#define XMALLOC(x) xrealloc(0,x)
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/* Here is perhaps the right place to mention that this code is
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* all in top-down order. Hence, |main| comes first.
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*/
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int
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main(int argc, char *argv[]) {
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int ch; /* used for |getopt| processing */
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(void) setlocale(LC_CTYPE, "");
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/* 1. Grok parameters. */
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while ((ch = getopt(argc, argv, "0123456789cd:hl:mpst:w:")) != -1)
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switch(ch) {
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case 'c':
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centerP = 1;
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continue;
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case 'd':
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sentence_enders = optarg;
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continue;
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case 'l':
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output_tab_width
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= get_nonnegative(optarg, "output tab width must be non-negative", 1);
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continue;
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case 'm':
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grok_mail_headers = 1;
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continue;
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case 'p':
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allow_indented_paragraphs = 1;
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continue;
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case 's':
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coalesce_spaces_P = 1;
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continue;
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case 't':
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tab_width = get_positive(optarg, "tab width must be positive", 1);
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continue;
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case 'w':
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goal_length = get_positive(optarg, "width must be positive", 1);
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max_length = goal_length;
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continue;
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case '0': case '1': case '2': case '3': case '4': case '5':
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case '6': case '7': case '8': case '9':
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/* XXX this is not a stylistically approved use of getopt() */
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if (goal_length==0) {
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char *p;
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p = argv[optind - 1];
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if (p[0] == '-' && p[1] == ch && !p[2])
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goal_length = get_positive(++p, "width must be nonzero", 1);
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else
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goal_length = get_positive(argv[optind]+1,
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"width must be nonzero", 1);
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max_length = goal_length;
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}
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continue;
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case 'h': default:
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fprintf(stderr,
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"Usage: fmt [-cmps] [-d chars] [-l num] [-t num]\n"
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" [-w width | -width | goal [maximum]] [file ...]\n"
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"Options: -c center each line instead of formatting\n"
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" -d <chars> double-space after <chars> at line end\n"
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" -l <n> turn each <n> spaces at start of line into a tab\n"
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" -m try to make sure mail header lines stay separate\n"
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" -p allow indented paragraphs\n"
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" -s coalesce whitespace inside lines\n"
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" -t <n> have tabs every <n> columns\n"
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" -w <n> set maximum width to <n>\n"
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" goal set target width to goal\n");
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exit(ch=='h' ? 0 : EX_USAGE);
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}
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argc -= optind; argv += optind;
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/* [ goal [ maximum ] ] */
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if (argc>0 && goal_length==0
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&& (goal_length=get_positive(*argv,"goal length must be positive", 0))
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!= 0) {
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--argc; ++argv;
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if (argc>0
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&& (max_length=get_positive(*argv,"max length must be positive", 0))
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!= 0) {
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--argc; ++argv;
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if (max_length<goal_length)
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errx(EX_USAGE, "max length must be >= goal length");
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}
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}
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if (goal_length==0) goal_length = 65;
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if (max_length==0) max_length = goal_length+10;
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output_buffer = XMALLOC(max_length+1); /* really needn't be longer */
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/* 2. Process files. */
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if (argc>0) {
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while (argc-->0) process_named_file(*argv++);
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}
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else {
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process_stream(stdin, "standard input");
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}
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/* We're done. */
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return n_errors ? EX_NOINPUT : 0;
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}
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/* Process a single file, given its name.
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*/
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static void
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process_named_file(const char *name) {
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FILE *f=fopen(name, "r");
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if (!f) { perror(name); ++n_errors; }
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else {
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process_stream(f, name);
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fclose(f);
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}
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}
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/* Types of mail header continuation lines:
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*/
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typedef enum {
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hdr_ParagraphStart = -1,
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hdr_NonHeader = 0,
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hdr_Header = 1,
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hdr_Continuation = 2
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} HdrType;
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/* Process a stream. This is where the real work happens,
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* except that centering is handled separately.
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*/
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static void
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process_stream(FILE *stream, const char *name) {
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size_t last_indent=SILLY; /* how many spaces in last indent? */
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size_t para_line_number=0; /* how many lines already read in this para? */
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size_t first_indent=SILLY; /* indentation of line 0 of paragraph */
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HdrType prev_header_type=hdr_ParagraphStart;
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/* ^-- header_type of previous line; -1 at para start */
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char *line;
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size_t length;
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if (centerP) { center_stream(stream, name); return; }
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while ((line=get_line(stream,&length)) != NULL) {
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size_t np=indent_length(line, length);
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{ HdrType header_type=hdr_NonHeader;
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if (grok_mail_headers && prev_header_type!=hdr_NonHeader) {
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if (np==0 && might_be_header(line))
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header_type = hdr_Header;
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else if (np>0 && prev_header_type>hdr_NonHeader)
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header_type = hdr_Continuation;
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}
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/* We need a new paragraph if and only if:
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* this line is blank,
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* OR it's a mail header,
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* OR it's not a mail header AND the last line was one,
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* OR the indentation has changed
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* AND the line isn't a mail header continuation line
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* AND this isn't the second line of an indented paragraph.
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*/
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if ( length==0
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|| header_type==hdr_Header
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|| (header_type==hdr_NonHeader && prev_header_type>hdr_NonHeader)
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|| (np!=last_indent
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&& header_type != hdr_Continuation
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&& (!allow_indented_paragraphs || para_line_number != 1)) ) {
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new_paragraph(output_in_paragraph ? last_indent : first_indent, np);
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para_line_number = 0;
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first_indent = np;
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last_indent = np;
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if (header_type==hdr_Header) last_indent=2; /* for cont. lines */
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if (length==0) {
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putchar('\n');
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prev_header_type=hdr_ParagraphStart;
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continue;
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}
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}
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else {
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/* If this is an indented paragraph other than a mail header
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* continuation, set |last_indent|.
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*/
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if (np != last_indent && header_type != hdr_Continuation)
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last_indent=np;
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}
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prev_header_type = header_type;
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}
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{ size_t n=np;
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while (n<length) {
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/* Find word end and count spaces after it */
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size_t word_length=0, space_length=0;
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while (n+word_length < length && line[n+word_length] != ' ')
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++word_length;
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space_length = word_length;
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while (n+space_length < length && line[n+space_length] == ' ')
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++space_length;
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/* Send the word to the output machinery. */
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output_word(first_indent, last_indent,
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line+n, word_length, space_length-word_length);
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n += space_length;
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}
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}
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++para_line_number;
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}
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new_paragraph(output_in_paragraph ? last_indent : first_indent, 0);
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if (ferror(stream)) { perror(name); ++n_errors; }
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}
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/* How long is the indent on this line?
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*/
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static size_t
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indent_length(const char *line, size_t length) {
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size_t n=0;
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while (n<length && *line++ == ' ') ++n;
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return n;
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}
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/* Might this line be a mail header?
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* We deem a line to be a possible header if it matches the
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* Perl regexp /^[A-Z][-A-Za-z0-9]*:\s/. This is *not* the same
|
|
* as in RFC whatever-number-it-is; we want to be gratuitously
|
|
* conservative to avoid mangling ordinary civilised text.
|
|
*/
|
|
static int
|
|
might_be_header(const unsigned char *line) {
|
|
if (!isupper(*line++)) return 0;
|
|
while (*line && (isalnum(*line) || *line=='-')) ++line;
|
|
return (*line==':' && isspace(line[1]));
|
|
}
|
|
|
|
/* Begin a new paragraph with an indent of |indent| spaces.
|
|
*/
|
|
static void
|
|
new_paragraph(size_t old_indent, size_t indent) {
|
|
if (x0) {
|
|
if (old_indent>0) output_indent(old_indent);
|
|
fwrite(output_buffer, 1, x0, stdout);
|
|
putchar('\n');
|
|
}
|
|
x=indent; x0=0; pending_spaces=0;
|
|
output_in_paragraph = 0;
|
|
}
|
|
|
|
/* Output spaces or tabs for leading indentation.
|
|
*/
|
|
static void
|
|
output_indent(size_t n_spaces) {
|
|
if (output_tab_width) {
|
|
while (n_spaces >= output_tab_width) {
|
|
putchar('\t');
|
|
n_spaces -= output_tab_width;
|
|
}
|
|
}
|
|
while (n_spaces-- > 0) putchar(' ');
|
|
}
|
|
|
|
/* Output a single word, or add it to the buffer.
|
|
* indent0 and indent1 are the indents to use on the first and subsequent
|
|
* lines of a paragraph. They'll often be the same, of course.
|
|
*/
|
|
static void
|
|
output_word(size_t indent0, size_t indent1, const char *word, size_t length, size_t spaces) {
|
|
size_t new_x = x+pending_spaces+length;
|
|
size_t indent = output_in_paragraph ? indent1 : indent0;
|
|
|
|
/* If either |spaces==0| (at end of line) or |coalesce_spaces_P|
|
|
* (squashing internal whitespace), then add just one space;
|
|
* except that if the last character was a sentence-ender we
|
|
* actually add two spaces.
|
|
*/
|
|
if (coalesce_spaces_P || spaces==0)
|
|
spaces = strchr(sentence_enders, word[length-1]) ? 2 : 1;
|
|
|
|
if (new_x<=goal_length) {
|
|
/* After adding the word we still aren't at the goal length,
|
|
* so clearly we add it to the buffer rather than outputing it.
|
|
*/
|
|
memset(output_buffer+x0, ' ', pending_spaces);
|
|
x0 += pending_spaces; x += pending_spaces;
|
|
memcpy(output_buffer+x0, word, length);
|
|
x0 += length; x += length;
|
|
pending_spaces = spaces;
|
|
}
|
|
else {
|
|
/* Adding the word takes us past the goal. Print the line-so-far,
|
|
* and the word too iff either (1) the lsf is empty or (2) that
|
|
* makes us nearer the goal but doesn't take us over the limit,
|
|
* or (3) the word on its own takes us over the limit.
|
|
* In case (3) we put a newline in between.
|
|
*/
|
|
if (indent>0) output_indent(indent);
|
|
fwrite(output_buffer, 1, x0, stdout);
|
|
if (x0==0 || (new_x <= max_length && new_x-goal_length <= goal_length-x)) {
|
|
printf("%*s", (int)pending_spaces, "");
|
|
goto write_out_word;
|
|
}
|
|
else {
|
|
/* If the word takes us over the limit on its own, just
|
|
* spit it out and don't bother buffering it.
|
|
*/
|
|
if (indent+length > max_length) {
|
|
putchar('\n');
|
|
if (indent>0) output_indent(indent);
|
|
write_out_word:
|
|
fwrite(word, 1, length, stdout);
|
|
x0 = 0; x = indent1; pending_spaces = 0;
|
|
}
|
|
else {
|
|
memcpy(output_buffer, word, length);
|
|
x0 = length; x = length+indent1; pending_spaces = spaces;
|
|
}
|
|
}
|
|
putchar('\n');
|
|
output_in_paragraph = 1;
|
|
}
|
|
}
|
|
|
|
/* Process a stream, but just center its lines rather than trying to
|
|
* format them neatly.
|
|
*/
|
|
static void
|
|
center_stream(FILE *stream, const char *name) {
|
|
char *line;
|
|
size_t length;
|
|
while ((line=get_line(stream, &length)) != 0) {
|
|
size_t l=length;
|
|
while (l>0 && isspace(*line)) { ++line; --l; }
|
|
length=l;
|
|
while (l<goal_length) { putchar(' '); l+=2; }
|
|
fwrite(line, 1, length, stdout);
|
|
putchar('\n');
|
|
}
|
|
if (ferror(stream)) { perror(name); ++n_errors; }
|
|
}
|
|
|
|
/* Get a single line from a stream. Expand tabs, strip control
|
|
* characters and trailing whitespace, and handle backspaces.
|
|
* Return the address of the buffer containing the line, and
|
|
* put the length of the line in |lengthp|.
|
|
* This can cope with arbitrarily long lines, and with lines
|
|
* without terminating \n.
|
|
* If there are no characters left or an error happens, we
|
|
* return 0.
|
|
* Don't confuse |spaces_pending| here with the global
|
|
* |pending_spaces|.
|
|
*/
|
|
static char *
|
|
get_line(FILE *stream, size_t *lengthp) {
|
|
static char *buf=NULL;
|
|
static size_t length=0;
|
|
size_t len=0;
|
|
int ch;
|
|
size_t spaces_pending=0;
|
|
|
|
if (buf==NULL) { length=100; buf=XMALLOC(length); }
|
|
while ((ch=getc(stream)) != '\n' && ch != EOF) {
|
|
if (ch==' ') ++spaces_pending;
|
|
else if (isprint(ch)) {
|
|
while (len+spaces_pending >= length) {
|
|
length*=2; buf=xrealloc(buf, length);
|
|
}
|
|
while (spaces_pending > 0) { --spaces_pending; buf[len++]=' '; }
|
|
buf[len++] = ch;
|
|
}
|
|
else if (ch=='\t')
|
|
spaces_pending += tab_width - (len+spaces_pending)%tab_width;
|
|
else if (ch=='\b') { if (len) --len; }
|
|
}
|
|
*lengthp=len;
|
|
return (len>0 || ch!=EOF) ? buf : 0;
|
|
}
|
|
|
|
/* (Re)allocate some memory, exiting with an error if we can't.
|
|
*/
|
|
static void *
|
|
xrealloc(void *ptr, size_t nbytes) {
|
|
void *p = realloc(ptr, nbytes);
|
|
if (p == NULL) errx(EX_OSERR, "out of memory");
|
|
return p;
|
|
}
|