coreutils-6.9coreutils-6.9

1 files changed, 540 insertions, 0 deletions

diff --git a/src/unexpand.c b/src/unexpand.c
new file mode 100644
index 0000000..cbceca0
--- /dev/null
+++ b/src/unexpand.c
@@ -0,0 +1,540 @@
+/* unexpand - convert blanks to tabs
+   Copyright (C) 89, 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.  */
+
+/* By default, convert only maximal strings of initial blanks and tabs
+   into tabs.
+   Preserves backspace characters in the output; they decrement the
+   column count for tab calculations.
+   The default action is equivalent to -8.
+
+   Options:
+   --tabs=tab1[,tab2[,...]]
+   -t tab1[,tab2[,...]]
+   -tab1[,tab2[,...]]	If only one tab stop is given, set the tabs tab1
+			columns apart instead of the default 8.  Otherwise,
+			set the tabs at columns tab1, tab2, etc. (numbered from
+			0); preserve any blanks beyond the tab stops given.
+   --all
+   -a			Use tabs wherever they would replace 2 or more blanks,
+			not just at the beginnings of lines.
+
+   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 "xstrndup.h"
+
+/* The official name of this program (e.g., no `g' prefix).  */
+#define PROGRAM_NAME "unexpand"
+
+#define AUTHORS "David MacKenzie"
+
+/* The number of bytes added at a time to the amount of memory
+   allocated for the output line.  */
+#define OUTPUT_BLOCK 256
+
+/* The name this program was run with.  */
+char *program_name;
+
+/* If true, convert blanks even after nonblank characters have been
+   read on the line.  */
+static bool convert_entire_line;
+
+/* If nonzero, the size of all tab stops.  If zero, use `tab_list' instead.  */
+static size_t tab_size;
+
+/* The maximum distance between tab stops.  */
+static size_t max_column_width;
+
+/* Array of the explicit column numbers of the tab stops;
+   after `tab_list' is exhausted, the rest of the line is printed
+   unchanged.  The first column is column 0.  */
+static uintmax_t *tab_list;
+
+/* The number of allocated entries in `tab_list'.  */
+static size_t n_tabs_allocated;
+
+/* The index of the first invalid element of `tab_list',
+   where the next element can be added.  */
+static size_t first_free_tab;
+
+/* Null-terminated array of input filenames.  */
+static char **file_list;
+
+/* Default for `file_list' if no files are given on the command line.  */
+static char *stdin_argv[] =
+{
+  "-", NULL
+};
+
+/* True if we have ever read standard input.  */
+static bool have_read_stdin;
+
+/* The desired exit status.  */
+static int exit_status;
+
+/* For long options that have no equivalent short option, use a
+   non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
+enum
+{
+  CONVERT_FIRST_ONLY_OPTION = CHAR_MAX + 1
+};
+
+static struct option const longopts[] =
+{
+  {"tabs", required_argument, NULL, 't'},
+  {"all", no_argument, NULL, 'a'},
+  {"first-only", no_argument, NULL, CONVERT_FIRST_ONLY_OPTION},
+  {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 (_("\
+Convert blanks in each FILE to tabs, writing to standard output.\n\
+With no FILE, or when FILE is -, read standard input.\n\
+\n\
+"), stdout);
+      fputs (_("\
+Mandatory arguments to long options are mandatory for short options too.\n\
+"), stdout);
+      fputs (_("\
+  -a, --all        convert all blanks, instead of just initial blanks\n\
+      --first-only  convert only leading sequences of blanks (overrides -a)\n\
+  -t, --tabs=N     have tabs N characters apart instead of 8 (enables -a)\n\
+  -t, --tabs=LIST  use comma separated LIST of tab positions (enables -a)\n\
+"), stdout);
+      fputs (HELP_OPTION_DESCRIPTION, stdout);
+      fputs (VERSION_OPTION_DESCRIPTION, stdout);
+      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+    }
+  exit (status);
+}
+
+/* Add tab stop TABVAL to the end of `tab_list'.  */
+
+static void
+add_tab_stop (uintmax_t tabval)
+{
+  uintmax_t prev_column = first_free_tab ? tab_list[first_free_tab - 1] : 0;
+  uintmax_t column_width = prev_column <= tabval ? tabval - prev_column : 0;
+
+  if (first_free_tab == n_tabs_allocated)
+    tab_list = X2NREALLOC (tab_list, &n_tabs_allocated);
+  tab_list[first_free_tab++] = tabval;
+
+  if (max_column_width < column_width)
+    {
+      if (SIZE_MAX < column_width)
+	error (EXIT_FAILURE, 0, _("tabs are too far apart"));
+      max_column_width = column_width;
+    }
+}
+
+/* Add the comma or blank separated list of tab stops STOPS
+   to the list of tab stops.  */
+
+static void
+parse_tab_stops (char const *stops)
+{
+  bool have_tabval = false;
+  uintmax_t tabval IF_LINT (= 0);
+  char const *num_start IF_LINT (= NULL);
+  bool ok = true;
+
+  for (; *stops; stops++)
+    {
+      if (*stops == ',' || isblank (to_uchar (*stops)))
+	{
+	  if (have_tabval)
+	    add_tab_stop (tabval);
+	  have_tabval = false;
+	}
+      else if (ISDIGIT (*stops))
+	{
+	  if (!have_tabval)
+	    {
+	      tabval = 0;
+	      have_tabval = true;
+	      num_start = stops;
+	    }
+
+	  /* Detect overflow.  */
+	  if (!DECIMAL_DIGIT_ACCUMULATE (tabval, *stops - '0', uintmax_t))
+	    {
+	      size_t len = strspn (num_start, "0123456789");
+	      char *bad_num = xstrndup (num_start, len);
+	      error (0, 0, _("tab stop is too large %s"), quote (bad_num));
+	      free (bad_num);
+	      ok = false;
+	      stops = num_start + len - 1;
+	    }
+	}
+      else
+	{
+	  error (0, 0, _("tab size contains invalid character(s): %s"),
+		 quote (stops));
+	  ok = false;
+	  break;
+	}
+    }
+
+  if (!ok)
+    exit (EXIT_FAILURE);
+
+  if (have_tabval)
+    add_tab_stop (tabval);
+}
+
+/* Check that the list of tab stops TABS, with ENTRIES entries,
+   contains only nonzero, ascending values.  */
+
+static void
+validate_tab_stops (uintmax_t const *tabs, size_t entries)
+{
+  uintmax_t prev_tab = 0;
+  size_t i;
+
+  for (i = 0; i < entries; i++)
+    {
+      if (tabs[i] == 0)
+	error (EXIT_FAILURE, 0, _("tab size cannot be 0"));
+      if (tabs[i] <= prev_tab)
+	error (EXIT_FAILURE, 0, _("tab sizes must be ascending"));
+      prev_tab = tabs[i];
+    }
+}
+
+/* Close the old stream pointer FP if it is non-NULL,
+   and return a new one opened to read the next input file.
+   Open a filename of `-' as the standard input.
+   Return NULL if there are no more input files.  */
+
+static FILE *
+next_file (FILE *fp)
+{
+  static char *prev_file;
+  char *file;
+
+  if (fp)
+    {
+      if (ferror (fp))
+	{
+	  error (0, errno, "%s", prev_file);
+	  exit_status = EXIT_FAILURE;
+	}
+      if (STREQ (prev_file, "-"))
+	clearerr (fp);		/* Also clear EOF.  */
+      else if (fclose (fp) != 0)
+	{
+	  error (0, errno, "%s", prev_file);
+	  exit_status = EXIT_FAILURE;
+	}
+    }
+
+  while ((file = *file_list++) != NULL)
+    {
+      if (STREQ (file, "-"))
+	{
+	  have_read_stdin = true;
+	  prev_file = file;
+	  return stdin;
+	}
+      fp = fopen (file, "r");
+      if (fp)
+	{
+	  prev_file = file;
+	  return fp;
+	}
+      error (0, errno, "%s", file);
+      exit_status = EXIT_FAILURE;
+    }
+  return NULL;
+}
+
+/* Change blanks to tabs, writing to stdout.
+   Read each file in `file_list', in order.  */
+
+static void
+unexpand (void)
+{
+  /* Input stream.  */
+  FILE *fp = next_file (NULL);
+
+  /* The array of pending blanks.  In non-POSIX locales, blanks can
+     include characters other than spaces, so the blanks must be
+     stored, not merely counted.  */
+  char *pending_blank;
+
+  if (!fp)
+    return;
+
+  /* The worst case is a non-blank character, then one blank, then a
+     tab stop, then MAX_COLUMN_WIDTH - 1 blanks, then a non-blank; so
+     allocate MAX_COLUMN_WIDTH bytes to store the blanks.  */
+  pending_blank = xmalloc (max_column_width);
+
+  for (;;)
+    {
+      /* Input character, or EOF.  */
+      int c;
+
+      /* If true, perform translations.  */
+      bool convert = true;
+
+
+      /* The following variables have valid values only when CONVERT
+	 is true:  */
+
+      /* Column of next input character.  */
+      uintmax_t column = 0;
+
+      /* Column the next input tab stop is on.  */
+      uintmax_t next_tab_column = 0;
+
+      /* Index in TAB_LIST of next tab stop to examine.  */
+      size_t tab_index = 0;
+
+      /* If true, the first pending blank came just before a tab stop.  */
+      bool one_blank_before_tab_stop = false;
+
+      /* If true, the previous input character was a blank.  This is
+	 initially true, since initial strings of blanks are treated
+	 as if the line was preceded by a blank.  */
+      bool prev_blank = true;
+
+      /* Number of pending columns of blanks.  */
+      size_t pending = 0;
+
+
+      /* Convert a line of text.  */
+
+      do
+	{
+	  while ((c = getc (fp)) < 0 && (fp = next_file (fp)))
+	    continue;
+
+	  if (convert)
+	    {
+	      bool blank = !! isblank (c);
+
+	      if (blank)
+		{
+		  if (next_tab_column <= column)
+		    {
+		      if (tab_size)
+			next_tab_column =
+			  column + (tab_size - column % tab_size);
+		      else
+			for (;;)
+			  if (tab_index == first_free_tab)
+			    {
+			      convert = false;
+			      break;
+			    }
+			  else
+			    {
+			      uintmax_t tab = tab_list[tab_index++];
+			      if (column < tab)
+				{
+				  next_tab_column = tab;
+				  break;
+				}
+			    }
+		    }
+
+		  if (convert)
+		    {
+		      if (next_tab_column < column)
+			error (EXIT_FAILURE, 0, _("input line is too long"));
+
+		      if (c == '\t')
+			{
+			  column = next_tab_column;
+
+			  /* Discard pending blanks, unless it was a single
+			     blank just before the previous tab stop.  */
+			  if (! (pending == 1 && one_blank_before_tab_stop))
+			    {
+			      pending = 0;
+			      one_blank_before_tab_stop = false;
+			    }
+			}
+		      else
+			{
+			  column++;
+
+			  if (! (prev_blank && column == next_tab_column))
+			    {
+			      /* It is not yet known whether the pending blanks
+				 will be replaced by tabs.  */
+			      if (column == next_tab_column)
+				one_blank_before_tab_stop = true;
+			      pending_blank[pending++] = c;
+			      prev_blank = true;
+			      continue;
+			    }
+
+			  /* Replace the pending blanks by a tab or two.  */
+			  pending_blank[0] = c = '\t';
+			  pending = one_blank_before_tab_stop;
+			}
+		    }
+		}
+	      else if (c == '\b')
+		{
+		  /* Go back one column, and force recalculation of the
+		     next tab stop.  */
+		  column -= !!column;
+		  next_tab_column = column;
+		  tab_index -= !!tab_index;
+		}
+	      else
+		{
+		  column++;
+		  if (!column)
+		    error (EXIT_FAILURE, 0, _("input line is too long"));
+		}
+
+	      if (pending)
+		{
+		  if (fwrite (pending_blank, 1, pending, stdout) != pending)
+		    error (EXIT_FAILURE, errno, _("write error"));
+		  pending = 0;
+		  one_blank_before_tab_stop = false;
+		}
+
+	      prev_blank = blank;
+	      convert &= convert_entire_line | blank;
+	    }
+
+	  if (c < 0)
+	    {
+	      free (pending_blank);
+	      return;
+	    }
+
+	  if (putchar (c) < 0)
+	    error (EXIT_FAILURE, errno, _("write error"));
+	}
+      while (c != '\n');
+    }
+}
+
+int
+main (int argc, char **argv)
+{
+  bool have_tabval = false;
+  uintmax_t tabval IF_LINT (= 0);
+  int c;
+
+  /* If true, cancel the effect of any -a (explicit or implicit in -t),
+     so that only leading blanks will be considered.  */
+  bool convert_first_only = false;
+
+  initialize_main (&argc, &argv);
+  program_name = argv[0];
+  setlocale (LC_ALL, "");
+  bindtextdomain (PACKAGE, LOCALEDIR);
+  textdomain (PACKAGE);
+
+  atexit (close_stdout);
+
+  have_read_stdin = false;
+  exit_status = EXIT_SUCCESS;
+  convert_entire_line = false;
+  tab_list = NULL;
+  first_free_tab = 0;
+
+  while ((c = getopt_long (argc, argv, ",0123456789at:", longopts, NULL))
+	 != -1)
+    {
+      switch (c)
+	{
+	case '?':
+	  usage (EXIT_FAILURE);
+	case 'a':
+	  convert_entire_line = true;
+	  break;
+	case 't':
+	  convert_entire_line = true;
+	  parse_tab_stops (optarg);
+	  break;
+	case CONVERT_FIRST_ONLY_OPTION:
+	  convert_first_only = true;
+	  break;
+	case ',':
+	  if (have_tabval)
+	    add_tab_stop (tabval);
+	  have_tabval = false;
+	  break;
+	case_GETOPT_HELP_CHAR;
+	case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+	default:
+	  if (!have_tabval)
+	    {
+	      tabval = 0;
+	      have_tabval = true;
+	    }
+	  if (!DECIMAL_DIGIT_ACCUMULATE (tabval, c - '0', uintmax_t))
+	    error (EXIT_FAILURE, 0, _("tab stop value is too large"));
+	  break;
+	}
+    }
+
+  if (convert_first_only)
+    convert_entire_line = false;
+
+  if (have_tabval)
+    add_tab_stop (tabval);
+
+  validate_tab_stops (tab_list, first_free_tab);
+
+  if (first_free_tab == 0)
+    tab_size = max_column_width = 8;
+  else if (first_free_tab == 1)
+    tab_size = tab_list[0];
+  else
+    tab_size = 0;
+
+  file_list = (optind < argc ? &argv[optind] : stdin_argv);
+
+  unexpand ();
+
+  if (have_read_stdin && fclose (stdin) != 0)
+    error (EXIT_FAILURE, errno, "-");
+
+  exit (exit_status);
+}