1 files changed, 318 insertions, 0 deletions
diff --git a/src/fold.c b/src/fold.c
new file mode 100644
index 0000000..0d4ea58
--- /dev/null
+++ b/src/fold.c
@@ -0,0 +1,318 @@
+/* fold -- wrap each input line to fit in specified width.
+   Copyright (C) 91, 1995-2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+/* Written by David MacKenzie, djm@gnu.ai.mit.edu. */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <getopt.h>
+#include <sys/types.h>
+
+#include "system.h"
+#include "error.h"
+#include "quote.h"
+#include "xstrtol.h"
+
+#define TAB_WIDTH 8
+
+/* The official name of this program (e.g., no `g' prefix).  */
+#define PROGRAM_NAME "fold"
+
+#define AUTHORS "David MacKenzie"
+
+/* The name this program was run with. */
+char *program_name;
+
+/* If nonzero, try to break on whitespace. */
+static bool break_spaces;
+
+/* If nonzero, count bytes, not column positions. */
+static bool count_bytes;
+
+/* If nonzero, at least one of the files we read was standard input. */
+static bool have_read_stdin;
+
+static char const shortopts[] = "bsw:0::1::2::3::4::5::6::7::8::9::";
+
+static struct option const longopts[] =
+{
+  {"bytes", no_argument, NULL, 'b'},
+  {"spaces", no_argument, NULL, 's'},
+  {"width", required_argument, NULL, 'w'},
+  {GETOPT_HELP_OPTION_DECL},
+  {GETOPT_VERSION_OPTION_DECL},
+  {NULL, 0, NULL, 0}
+};
+
+void
+usage (int status)
+{
+  if (status != EXIT_SUCCESS)
+    fprintf (stderr, _("Try `%s --help' for more information.\n"),
+	     program_name);
+  else
+    {
+      printf (_("\
+Usage: %s [OPTION]... [FILE]...\n\
+"),
+	      program_name);
+      fputs (_("\
+Wrap input lines in each FILE (standard input by default), writing to\n\
+standard output.\n\
+\n\
+"), stdout);
+      fputs (_("\
+Mandatory arguments to long options are mandatory for short options too.\n\
+"), stdout);
+      fputs (_("\
+  -b, --bytes         count bytes rather than columns\n\
+  -s, --spaces        break at spaces\n\
+  -w, --width=WIDTH   use WIDTH columns instead of 80\n\
+"), stdout);
+      fputs (HELP_OPTION_DESCRIPTION, stdout);
+      fputs (VERSION_OPTION_DESCRIPTION, stdout);
+      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+    }
+  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 size_t
+adjust_column (size_t column, char c)
+{
+  if (!count_bytes)
+    {
+      if (c == '\b')
+	{
+	  if (column > 0)
+	    column--;
+	}
+      else if (c == '\r')
+	column = 0;
+      else if (c == '\t')
+	column += TAB_WIDTH - column % TAB_WIDTH;
+      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 true if successful.  */
+
+static bool
+fold_file (char const *filename, size_t width)
+{
+  FILE *istream;
+  int c;
+  size_t 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;
+  int saved_errno;
+
+  if (STREQ (filename, "-"))
+    {
+      istream = stdin;
+      have_read_stdin = true;
+    }
+  else
+    istream = fopen (filename, "r");
+
+  if (istream == NULL)
+    {
+      error (0, errno, "%s", filename);
+      return false;
+    }
+
+  while ((c = getc (istream)) != EOF)
+    {
+      if (offset_out + 1 >= allocated_out)
+	line_out = X2REALLOC (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)
+	    {
+	      bool found_blank = false;
+	      size_t logical_end = offset_out;
+
+	      /* Look for the last blank. */
+	      while (logical_end)
+		{
+		  --logical_end;
+		  if (isblank (to_uchar (line_out[logical_end])))
+		    {
+		      found_blank = true;
+		      break;
+		    }
+		}
+
+	      if (found_blank)
+		{
+		  size_t i;
+
+		  /* 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;
+		}
+	    }
+
+	  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;
+    }
+
+  saved_errno = errno;
+
+  if (offset_out)
+    fwrite (line_out, sizeof (char), (size_t) offset_out, stdout);
+
+  if (ferror (istream))
+    {
+      error (0, saved_errno, "%s", filename);
+      if (!STREQ (filename, "-"))
+	fclose (istream);
+      return false;
+    }
+  if (!STREQ (filename, "-") && fclose (istream) == EOF)
+    {
+      error (0, errno, "%s", filename);
+      return false;
+    }
+
+  return true;
+}
+
+int
+main (int argc, char **argv)
+{
+  size_t width = 80;
+  int i;
+  int optc;
+  bool ok;
+
+  initialize_main (&argc, &argv);
+  program_name = argv[0];
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  atexit (close_stdout);
+
+  break_spaces = count_bytes = have_read_stdin = false;
+
+  while ((optc = getopt_long (argc, argv, shortopts, longopts, NULL)) != -1)
+    {
+      char optargbuf[2];
+
+      switch (optc)
+	{
+	case 'b':		/* Count bytes rather than columns. */
+	  count_bytes = true;
+	  break;
+
+	case 's':		/* Break at word boundaries. */
+	  break_spaces = true;
+	  break;
+
+	case '0': case '1': case '2': case '3': case '4':
+	case '5': case '6': case '7': case '8': case '9':
+	  if (optarg)
+	    optarg--;
+	  else
+	    {
+	      optargbuf[0] = optc;
+	      optargbuf[1] = '\0';
+	      optarg = optargbuf;
+	    }
+	  /* Fall through.  */
+	case 'w':		/* Line width. */
+	  {
+	    unsigned long int tmp_ulong;
+	    if (! (xstrtoul (optarg, NULL, 10, &tmp_ulong, "") == LONGINT_OK
+		   && 0 < tmp_ulong && tmp_ulong < SIZE_MAX - TAB_WIDTH))
+	      error (EXIT_FAILURE, 0,
+		     _("invalid number of columns: %s"), quote (optarg));
+	    width = tmp_ulong;
+	  }
+	  break;
+
+	case_GETOPT_HELP_CHAR;
+
+	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+
+	default:
+	  usage (EXIT_FAILURE);
+	}
+    }
+
+  if (argc == optind)
+    ok = fold_file ("-", width);
+  else
+    {
+      ok = true;
+      for (i = optind; i < argc; i++)
+	ok &= fold_file (argv[i], width);
+    }
+
+  if (have_read_stdin && fclose (stdin) == EOF)
+    error (EXIT_FAILURE, errno, "-");
+
+  exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
+}