remove support for the 'L' (fmt/flow-paragraph) command

* sed/Makefile.am (sed_SOURCES): Remove fmt.c.
* sed/execute.c (execute_program):
* sed/fmt.c: Remove file.
* sed/sed.h (fmt): Remove declaration.
* doc/sed.texi: Remove documentation for 'L' command.
* doc/sed-in.texi: Likewise.
* NEWS (Feature removal): Document it.
Prompted by the report from Jodie Cunningham that using this
command with a large number could cause sed to segfault:
https://bugs.launchpad.net/ubuntu/+source/sed/+bug/1400575

7 files changed, 7 insertions, 645 deletions

diff --git a/NEWS b/NEWS
index 19390a4..b713b1d 100644
--- a/NEWS
+++ b/NEWS
@@ -13,6 +13,12 @@ GNU sed NEWS                                    -*- outline -*-
   is what stopped working. [bug introduced some time after sed-3.02 and
   prior to the first sed-4* test release]
 
+** Feature removal
+
+  The "L" command (format a paragraph like the fmt(1) command would)
+  has been listed in the documentation as a failed experiment for at
+  least 10 years.  That command is now removed.
+
 ** Build-related
 
   "make dist" now builds .tar.xz files, rather than .tar.gz ones.
diff --git a/doc/sed-in.texi b/doc/sed-in.texi
index a1f2cbd..5f932c1 100644
--- a/doc/sed-in.texi
+++ b/doc/sed-in.texi
@@ -1468,33 +1468,6 @@ to the end of the current cycle.
 Print out the file name of the current input file (with a trailing
 newline).
 
-@item L @var{n}
-@findex L (fLow paragraphs) command
-@cindex Reformat pattern space
-@cindex Reformatting paragraphs
-@cindex @value{SSEDEXT}, reformatting paragraphs
-@cindex @value{SSEDEXT}, @code{L} command
-This @value{SSED} extension fills and joins lines in pattern space
-to produce output lines of (at most) @var{n} characters, like
-@code{fmt} does; if @var{n} is omitted, the default as specified
-on the command line is used.  This command is considered a failed
-experiment and unless there is enough request (which seems unlikely)
-will be removed in future versions.
-
-@ignore
-Blank lines, spaces between words, and indentation are
-preserved in the output; successive input lines with different
-indentation are not joined; tabs are expanded to 8 columns.
-
-If the pattern space contains multiple lines, they are joined, but
-since the pattern space usually contains a single line, the behavior
-of a simple @code{L;d} script is the same as @samp{fmt -s} (i.e.,
-it does not join short lines to form longer ones).
-
-@var{n} specifies the desired line-wrap length; if omitted,
-the default as specified on the command line is used.
-@end ignore
-
 @item Q [@var{exit-code}]
 This command only accepts a single address.
 
diff --git a/doc/sed.texi b/doc/sed.texi
index b4de5f3..412454c 100644
--- a/doc/sed.texi
+++ b/doc/sed.texi
@@ -1469,33 +1469,6 @@ to the end of the current cycle.
 Print out the file name of the current input file (with a trailing
 newline).
 
-@item L @var{n}
-@findex L (fLow paragraphs) command
-@cindex Reformat pattern space
-@cindex Reformatting paragraphs
-@cindex @value{SSEDEXT}, reformatting paragraphs
-@cindex @value{SSEDEXT}, @code{L} command
-This @value{SSED} extension fills and joins lines in pattern space
-to produce output lines of (at most) @var{n} characters, like
-@code{fmt} does; if @var{n} is omitted, the default as specified
-on the command line is used.  This command is considered a failed
-experiment and unless there is enough request (which seems unlikely)
-will be removed in future versions.
-
-@ignore
-Blank lines, spaces between words, and indentation are
-preserved in the output; successive input lines with different
-indentation are not joined; tabs are expanded to 8 columns.
-
-If the pattern space contains multiple lines, they are joined, but
-since the pattern space usually contains a single line, the behavior
-of a simple @code{L;d} script is the same as @samp{fmt -s} (i.e.,
-it does not join short lines to form longer ones).
-
-@var{n} specifies the desired line-wrap length; if omitted,
-the default as specified on the command line is used.
-@end ignore
-
 @item Q [@var{exit-code}]
 This command only accepts a single address.
 
diff --git a/sed/Makefile.am b/sed/Makefile.am
index 243ac4b..1983810 100644
--- a/sed/Makefile.am
+++ b/sed/Makefile.am
@@ -3,7 +3,7 @@ bin_PROGRAMS = sed
 
 localedir = $(datadir)/locale
 
-sed_SOURCES = sed.c compile.c execute.c regexp.c fmt.c mbcs.c utils.c
+sed_SOURCES = sed.c compile.c execute.c regexp.c mbcs.c utils.c
 noinst_HEADERS = sed.h utils.h
 
 AM_CPPFLAGS = -I$(top_srcdir)/lib -I$(top_srcdir) -I$(top_builddir)/lib \
diff --git a/sed/execute.c b/sed/execute.c
index fa6fe1d..f398e7c 100644
--- a/sed/execute.c
+++ b/sed/execute.c
@@ -1353,16 +1353,6 @@ execute_program(struct vector *vec, struct input *input)
                       : cur_cmd->x.int_arg);
               break;
 
-            case 'L':
-              output_missing_newline(&output_file);
-              fmt(line.active, line.active + line.length,
-                  cur_cmd->x.int_arg == -1
-                  ? lcmd_out_line_len
-                  : cur_cmd->x.int_arg,
-                  output_file.fp);
-              flush_output(output_file.fp);
-              break;
-
             case 'n':
               if (!no_default_output)
                 output_line(line.active, line.length, line.chomped, &output_file);
diff --git a/sed/fmt.c b/sed/fmt.c
deleted file mode 100644
index 389bccb..0000000
--- a/sed/fmt.c
+++ /dev/null
@@ -1,578 +0,0 @@
-/* `L' command implementation for GNU sed, based on GNU fmt 1.22.
-   Copyright (C) 1994, 1995, 1996, 2002, 2003, 2014 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 3, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
-
-/* GNU fmt was written by Ross Paterson <rap@doc.ic.ac.uk>.  */
-
-#include "sed.h"
-
-#include <stdio.h>
-#include <string.h>
-#include <ctype.h>
-#include <sys/types.h>
-#include <limits.h>
-
-/* The following parameters represent the program's idea of what is
-   "best".  Adjust to taste, subject to the caveats given.  */
-
-/* Prefer lines to be LEEWAY % shorter than the maximum width, giving
-   room for optimization.  */
-#define	LEEWAY	7
-
-/* Costs and bonuses are expressed as the equivalent departure from the
-   optimal line length, multiplied by 10.  e.g. assigning something a
-   cost of 50 means that it is as bad as a line 5 characters too short
-   or too long.  The definition of SHORT_COST(n) should not be changed.
-   However, EQUIV(n) may need tuning.  */
-
-typedef long COST;
-
-#define	MAXCOST	(~(((unsigned long) 1) << (8 * sizeof (COST) -1)))
-
-#define	SQR(n)		((n) * (n))
-#define	EQUIV(n)	SQR ((COST) (n))
-
-/* Cost of a filled line n chars longer or shorter than best_width.  */
-#define	SHORT_COST(n)	EQUIV ((n) * 10)
-
-/* Cost of the difference between adjacent filled lines.  */
-#define	RAGGED_COST(n)	(SHORT_COST (n) / 2)
-
-/* Basic cost per line.  */
-#define	LINE_COST	EQUIV (70)
-
-/* Cost of breaking a line after the first word of a sentence, where
-   the length of the word is N.  */
-#define	WIDOW_COST(n)	(EQUIV (200) / ((n) + 2))
-
-/* Cost of breaking a line before the last word of a sentence, where
-   the length of the word is N.  */
-#define	ORPHAN_COST(n)	(EQUIV (150) / ((n) + 2))
-
-/* Bonus for breaking a line at the end of a sentence.  */
-#define	SENTENCE_BONUS	EQUIV (50)
-
-/* Cost of breaking a line after a period not marking end of a sentence.
-   With the definition of sentence we are using (borrowed from emacs, see
-   get_line()) such a break would then look like a sentence break.  Hence
-   we assign a very high cost -- it should be avoided unless things are
-   really bad.  */
-#define	NOBREAK_COST	EQUIV (600)
-
-/* Bonus for breaking a line before open parenthesis.  */
-#define	PAREN_BONUS	EQUIV (40)
-
-/* Bonus for breaking a line after other punctuation.  */
-#define	PUNCT_BONUS	EQUIV(40)
-
-/* Credit for breaking a long paragraph one line later.  */
-#define	LINE_CREDIT	EQUIV(3)
-
-/* Size of paragraph buffer in words.  Longer paragraphs are handled
-   neatly (cf. flush_paragraph()), so there's little to gain by making
-   these larger.  */
-#define	MAXWORDS	1000
-
-#define GETC()          (parabuf == end_of_parabuf ? EOF : *parabuf++)
-
-/* Extra ctype(3)-style macros.  */
-
-#define	isopen(c)	(strchr ("([`'\"", (c)) != NULL)
-#define	isclose(c)	(strchr (")]'\"", (c)) != NULL)
-#define	isperiod(c)	(strchr (".?!", (c)) != NULL)
-
-/* Size of a tab stop, for expansion on input and re-introduction on
-   output.  */
-#define	TABWIDTH	8
-
-/* Word descriptor structure.  */
-
-typedef struct Word WORD;
-
-struct Word
-  {
-
-    /* Static attributes determined during input.  */
-
-    const char *text;		/* the text of the word */
-    short length;		/* length of this word */
-    short space;		/* the size of the following space */
-    unsigned paren:1;		/* starts with open paren */
-    unsigned period:1;		/* ends in [.?!])* */
-    unsigned punct:1;		/* ends in punctuation */
-    unsigned final:1;		/* end of sentence */
-
-    /* The remaining fields are computed during the optimization.  */
-
-    short line_length;		/* length of the best line starting here */
-    COST best_cost;		/* cost of best paragraph starting here */
-    WORD *next_break;		/* break which achieves best_cost */
-  };
-
-/* Forward declarations.  */
-
-static bool get_paragraph (void);
-static int get_line (int c);
-static int get_space (int c);
-static int copy_rest (int c);
-static bool same_para (int c);
-static void flush_paragraph (void);
-static void fmt_paragraph (void);
-static void check_punctuation (WORD *w);
-static COST base_cost (WORD *this);
-static COST line_cost (WORD *next, int len);
-static void put_paragraph (WORD *finish);
-static void put_line (WORD *w, int indent);
-static void put_word (WORD *w);
-static void put_space (int space);
-
-/* Option values.  */
-
-/* User-supplied maximum line width (default WIDTH).  The only output
-   lines
-   longer than this will each comprise a single word.  */
-static int max_width;
-
-/* Space for the paragraph text.  */
-static const char *parabuf;
-
-/* End of space for the paragraph text.  */
-static const char *end_of_parabuf;
-
-/* The file on which we output */
-static FILE *outfile;
-
-/* Values derived from the option values.  */
-
-/* The preferred width of text lines, set to LEEWAY % less than max_width.  */
-static int best_width;
-
-/* Dynamic variables.  */
-
-/* Start column of the character most recently read from the input file.  */
-static int in_column;
-
-/* Start column of the next character to be written to stdout.  */
-static int out_column;
-
-/* The words of a paragraph -- longer paragraphs are handled neatly
-   (cf. flush_paragraph()).  */
-static WORD words[MAXWORDS];
-
-/* A pointer into the above word array, indicating the first position
-   after the last complete word.  Sometimes it will point at an incomplete
-   word.  */
-static WORD *word_limit;
-
-/* Indentation of the first line of the current paragraph.  */
-static int first_indent;
-
-/* Indentation of other lines of the current paragraph */
-static int other_indent;
-
-/* The last character read from the input file.  */
-static int next_char;
-
-/* If nonzero, the length of the last line output in the current
-   paragraph, used to charge for raggedness at the split point for long
-   paragraphs chosen by fmt_paragraph().  */
-static int last_line_length;
-
-/* read file F and send formatted output to stdout.  */
-
-void
-fmt (const char *line, const char *line_end, int max_length, FILE *output_file)
-{
-  parabuf = line;
-  end_of_parabuf = line_end;
-  outfile = output_file;
-
-  max_width = max_length;
-  best_width = max_width * (201 - 2 * LEEWAY) / 200;
-
-  in_column = 0;
-  other_indent = 0;
-  next_char = GETC();
-  while (get_paragraph ())
-    {
-      fmt_paragraph ();
-      put_paragraph (word_limit);
-    }
-}
-
-/* Read a paragraph from input file F.  A paragraph consists of a
-   maximal number of non-blank (excluding any prefix) lines
-   with the same indent.
-
-   Return false if end-of-file was encountered before the start of a
-   paragraph, else true.  */
-
-static bool
-get_paragraph (void)
-{
-  register int c;
-
-  last_line_length = 0;
-  c = next_char;
-
-  /* Scan (and copy) blank lines, and lines not introduced by the prefix.  */
-
-  while (c == '\n' || c == EOF)
-    {
-      c = copy_rest (c);
-      if (c == EOF)
-        {
-          next_char = EOF;
-          return false;
-        }
-      putc ('\n', outfile);
-      c = GETC();
-    }
-
-  /* Got a suitable first line for a paragraph.  */
-
-  first_indent = in_column;
-  word_limit = words;
-  c = get_line (c);
-
-  /* Read rest of paragraph.  */
-
-  other_indent = in_column;
-  while (same_para (c) && in_column == other_indent)
-    c = get_line (c);
-
-  (word_limit - 1)->period = (word_limit - 1)->final = true;
-  next_char = c;
-  return true;
-}
-
-/* Copy to the output a blank line.  In the latter, C is \n or EOF.
-   Return the character (\n or EOF) ending the line.  */
-
-static int
-copy_rest (register int c)
-{
-  out_column = 0;
-  while (c != '\n' && c != EOF)
-    {
-      putc (c, outfile);
-      c = GETC();
-    }
-  return c;
-}
-
-/* Return true if a line whose first non-blank character after the
-   prefix (if any) is C could belong to the current paragraph,
-   otherwise false.  */
-
-static bool
-same_para (register int c)
-{
-  return (c != '\n' && c != EOF);
-}
-
-/* Read a line from the input data given first non-blank character C
-   after the prefix, and the following indent, and break it into words.
-   A word is a maximal non-empty string of non-white characters.  A word
-   ending in [.?!]["')\]]* and followed by end-of-line or at least two
-   spaces ends a sentence, as in emacs.
-
-   Return the first non-blank character of the next line.  */
-
-static int
-get_line (register int c)
-{
-  int start;
-  register WORD *end_of_word;
-
-  end_of_word = &words[MAXWORDS - 2];
-
-  do
-    {				/* for each word in a line */
-
-      /* Scan word.  */
-
-      word_limit->text = parabuf - 1;
-      do
-        c = GETC();
-      while (c != EOF && !ISSPACE (c));
-      word_limit->length = parabuf - word_limit->text - (c != EOF);
-      in_column += word_limit->length;
-
-      check_punctuation (word_limit);
-
-      /* Scan inter-word space.  */
-
-      start = in_column;
-      c = get_space (c);
-      word_limit->space = in_column - start;
-      word_limit->final = (c == EOF
-                           || (word_limit->period
-                               && (c == '\n' || word_limit->space > 1)));
-      if (c == '\n' || c == EOF)
-        word_limit->space = word_limit->final ? 2 : 1;
-      if (word_limit == end_of_word)
-        flush_paragraph ();
-      word_limit++;
-      if (c == EOF)
-        {
-          in_column = first_indent;
-          return EOF;
-        }
-    }
-  while (c != '\n');
-
-  in_column = 0;
-  c = GETC();
-  return get_space (c);
-}
-
-/* Read blank characters from the input data, starting with C, and keeping
-   in_column up-to-date.  Return first non-blank character.  */
-
-static int
-get_space (register int c)
-{
-  for (;;)
-    {
-      if (c == ' ')
-        in_column++;
-      else if (c == '\t')
-        in_column = (in_column / TABWIDTH + 1) * TABWIDTH;
-      else
-        return c;
-      c = GETC();
-    }
-}
-
-/* Set extra fields in word W describing any attached punctuation.  */
-
-static void
-check_punctuation (register WORD *w)
-{
-  register const char *start, *finish;
-
-  start = w->text;
-  finish = start + (w->length - 1);
-  w->paren = isopen (*start);
-  w->punct = ISPUNCT (*finish);
-  while (isclose (*finish) && finish > start)
-    finish--;
-  w->period = isperiod (*finish);
-}
-
-/* Flush part of the paragraph to make room.  This function is called on
-   hitting the limit on the number of words or characters.  */
-
-static void
-flush_paragraph (void)
-{
-  WORD *split_point;
-  register WORD *w;
-  COST best_break;
-
-  /* - format what you have so far as a paragraph,
-     - find a low-cost line break near the end,
-     - output to there,
-     - make that the start of the paragraph.  */
-
-  fmt_paragraph ();
-
-  /* Choose a good split point.  */
-
-  split_point = word_limit;
-  best_break = MAXCOST;
-  for (w = words->next_break; w != word_limit; w = w->next_break)
-    {
-      if (w->best_cost - w->next_break->best_cost < best_break)
-        {
-          split_point = w;
-          best_break = w->best_cost - w->next_break->best_cost;
-        }
-      if (best_break <= MAXCOST - LINE_CREDIT)
-        best_break += LINE_CREDIT;
-    }
-  put_paragraph (split_point);
-
-  /* Copy words from split_point down to word -- we use memmove because
-     the source and target may overlap.  */
-
-  memmove ((char *) words, (char *) split_point,
-         (word_limit - split_point + 1) * sizeof (WORD));
-  word_limit -= split_point - words;
-}
-
-/* Compute the optimal formatting for the whole paragraph by computing
-   and remembering the optimal formatting for each suffix from the empty
-   one to the whole paragraph.  */
-
-static void
-fmt_paragraph (void)
-{
-  register WORD *start, *w;
-  register int len;
-  register COST wcost, best;
-  int saved_length;
-
-  word_limit->best_cost = 0;
-  saved_length = word_limit->length;
-  word_limit->length = max_width;	/* sentinel */
-
-  for (start = word_limit - 1; start >= words; start--)
-    {
-      best = MAXCOST;
-      len = start == words ? first_indent : other_indent;
-
-      /* At least one word, however long, in the line.  */
-
-      w = start;
-      len += w->length;
-      do
-        {
-          w++;
-
-          /* Consider breaking before w.  */
-
-          wcost = line_cost (w, len) + w->best_cost;
-          if (start == words && last_line_length > 0)
-            wcost += RAGGED_COST (len - last_line_length);
-          if (wcost < best)
-            {
-              best = wcost;
-              start->next_break = w;
-              start->line_length = len;
-            }
-          len += (w - 1)->space + w->length;	/* w > start >= words */
-        }
-      while (len < max_width);
-      start->best_cost = best + base_cost (start);
-    }
-
-  word_limit->length = saved_length;
-}
-
-/* Return the constant component of the cost of breaking before the
-   word THIS.  */
-
-static COST
-base_cost (register WORD *this)
-{
-  register COST cost;
-
-  cost = LINE_COST;
-
-  if (this > words)
-    {
-      if ((this - 1)->period)
-        {
-          if ((this - 1)->final)
-            cost -= SENTENCE_BONUS;
-          else
-            cost += NOBREAK_COST;
-        }
-      else if ((this - 1)->punct)
-        cost -= PUNCT_BONUS;
-      else if (this > words + 1 && (this - 2)->final)
-        cost += WIDOW_COST ((this - 1)->length);
-    }
-
-  if (this->paren)
-    cost -= PAREN_BONUS;
-  else if (this->final)
-    cost += ORPHAN_COST (this->length);
-
-  return cost;
-}
-
-/* Return the component of the cost of breaking before word NEXT that
-   depends on LEN, the length of the line beginning there.  */
-
-static COST
-line_cost (register WORD *next, register int len)
-{
-  register int n;
-  register COST cost;
-
-  if (next == word_limit)
-    return 0;
-  n = best_width - len;
-  cost = SHORT_COST (n);
-  if (next->next_break != word_limit)
-    {
-      n = len - next->line_length;
-      cost += RAGGED_COST (n);
-    }
-  return cost;
-}
-
-/* Output to stdout a paragraph from word up to (but not including)
-   FINISH, which must be in the next_break chain from word.  */
-
-static void
-put_paragraph (register WORD *finish)
-{
-  register WORD *w;
-
-  put_line (words, first_indent);
-  for (w = words->next_break; w != finish; w = w->next_break)
-    put_line (w, other_indent);
-}
-
-/* Output to stdout the line beginning with word W, beginning in column
-   INDENT, including the prefix (if any).  */
-
-static void
-put_line (register WORD *w, int indent)
-{
-  register WORD *endline;
-  out_column = 0;
-  put_space (indent);
-
-  endline = w->next_break - 1;
-  for (; w != endline; w++)
-    {
-      put_word (w);
-      put_space (w->space);
-    }
-  put_word (w);
-  last_line_length = out_column;
-  putc ('\n', outfile);
-}
-
-/* Output to stdout the word W.  */
-
-static void
-put_word (register WORD *w)
-{
-  register const char *s;
-  register int n;
-
-  s = w->text;
-  for (n = w->length; n != 0; n--)
-    putc (*s++, outfile);
-  out_column += w->length;
-}
-
-/* Output to stdout SPACE spaces, or equivalent tabs.  */
-
-static void
-put_space (int space)
-{
-  out_column += space;
-  while (space--)
-    putc (' ', outfile);
-}
diff --git a/sed/sed.h b/sed/sed.h
index c3700b0..1f7456f 100644
--- a/sed/sed.h
+++ b/sed/sed.h
@@ -201,8 +201,6 @@ int process_files (struct vector *, char **argv);
 
 int main (int, char **);
 
-extern void fmt (const char *line, const char *line_end, int max_length, FILE *output_file);
-
 extern int extended_regexp_flags;
 
 /* one-byte buffer delimiter */