Delete wordexp. There isn't much point in having this since

so few apps use it, and it is just a stub anyways.  Better
to just skip it.

1 files changed, 0 insertions, 2411 deletions

diff --git a/libc/misc/wordexp/wordexp.c b/libc/misc/wordexp/wordexp.c
deleted file mode 100644
index 9e468d6a5..000000000
--- a/libc/misc/wordexp/wordexp.c
+++ /dev/null
@@ -1,2411 +0,0 @@
-/* POSIX.2 wordexp implementation.
-   Copyright (C) 1997, 1998, 1999 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Contributed by Tim Waugh <tim@cyberelk.demon.co.uk>.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Library General Public License as
-   published by the Free Software Foundation; either version 2 of the
-   License, or (at your option) any later version.
-
-   The GNU C Library 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
-   Library General Public License for more details.
-
-   You should have received a copy of the GNU Library General Public
-   License along with the GNU C Library; see the file COPYING.LIB.  If not,
-   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-   Boston, MA 02111-1307, USA.  */
-
-#include <wordexp.h>
-#include <signal.h>
-#include <stdlib.h>
-#include <pwd.h>
-#include <sys/types.h>
-#include <string.h>
-#include <glob.h>
-#include <ctype.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <sys/stat.h>
-#include <paths.h>
-#include <errno.h>
-#include <sys/param.h>
-#include <stdio.h>
-#include <fnmatch.h>
-
-/* Undefine the following line for the production version.  */
-/* #define NDEBUG 1 */
-#include <assert.h>
-
-/*
- * This is a recursive-descent-style word expansion routine.
- */
-
-/* These variables are defined and initialized in the startup code.  */
-extern int __libc_argc;
-extern char **__libc_argv;
-
-/* Some forward declarations */
-static int parse_dollars (char **word, size_t *word_length, size_t *max_length,
-			  const char *words, size_t *offset, int flags,
-			  wordexp_t *pwordexp, const char *ifs,
-			  const char *ifs_white, int quoted);
-static int parse_backtick (char **word, size_t *word_length,
-			   size_t *max_length, const char *words,
-			   size_t *offset, int flags, wordexp_t *pwordexp,
-			   const char *ifs, const char *ifs_white);
-static int parse_dquote (char **word, size_t *word_length, size_t *max_length,
-			 const char *words, size_t *offset, int flags,
-			 wordexp_t *pwordexp, const char *ifs,
-			 const char *ifs_white);
-static int eval_expr (char *expr, long int *result);
-
-/* The w_*() functions manipulate word lists. */
-
-#define W_CHUNK	(100)
-
-/* Result of w_newword will be ignored if it's the last word. */
-static inline char *
-w_newword (size_t *actlen, size_t *maxlen)
-{
-  *actlen = *maxlen = 0;
-  return NULL;
-}
-
-static inline char *
-w_addchar (char *buffer, size_t *actlen, size_t *maxlen, char ch)
-     /* (lengths exclude trailing zero) */
-{
-  /* Add a character to the buffer, allocating room for it if needed.
-   */
-
-  if (*actlen == *maxlen)
-    {
-      char *old_buffer = buffer;
-      assert (buffer == NULL || *maxlen != 0);
-      *maxlen += W_CHUNK;
-      buffer = realloc (buffer, 1 + *maxlen);
-
-      if (buffer == NULL)
-	free (old_buffer);
-    }
-
-  if (buffer != NULL)
-    {
-      buffer[*actlen] = ch;
-      buffer[++(*actlen)] = '\0';
-    }
-
-  return buffer;
-}
-
-static char *
-w_addmem (char *buffer, size_t *actlen, size_t *maxlen, const char *str,
-	  size_t len)
-{
-  /* Add a string to the buffer, allocating room for it if needed.
-   */
-  if (*actlen + len > *maxlen)
-    {
-      char *old_buffer = buffer;
-      assert (buffer == NULL || *maxlen != 0);
-      *maxlen += MAX (2 * len, W_CHUNK);
-      buffer = realloc (old_buffer, 1 + *maxlen);
-
-      if (buffer == NULL)
-	free (old_buffer);
-    }
-
-  if (buffer != NULL)
-    {
-      *((char *) mempcpy (&buffer[*actlen], str, len)) = '\0';
-      *actlen += len;
-    }
-
-  return buffer;
-}
-
-static char *
-w_addstr (char *buffer, size_t *actlen, size_t *maxlen, const char *str)
-     /* (lengths exclude trailing zero) */
-{
-  /* Add a string to the buffer, allocating room for it if needed.
-   */
-  size_t len;
-
-  assert (str != NULL); /* w_addstr only called from this file */
-  len = strlen (str);
-
-  return w_addmem (buffer, actlen, maxlen, str, len);
-}
-
-static int
-w_addword (wordexp_t *pwordexp, char *word)
-{
-  /* Add a word to the wordlist */
-  size_t num_p;
-  char **new_wordv;
-
-  /* Internally, NULL acts like "".  Convert NULLs to "" before
-   * the caller sees them.
-   */
-  if (word == NULL)
-    {
-      word = strdup ("");
-      if (word == NULL)
-	goto no_space;
-    }
-
-  num_p = 2 + pwordexp->we_wordc + pwordexp->we_offs;
-  new_wordv = realloc (pwordexp->we_wordv, sizeof (char *) * num_p);
-  if (new_wordv != NULL)
-    {
-      pwordexp->we_wordv = new_wordv;
-      pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc++] = word;
-      pwordexp->we_wordv[pwordexp->we_offs + pwordexp->we_wordc] = NULL;
-      return 0;
-    }
-
-no_space:
-  return WRDE_NOSPACE;
-}
-
-/* The parse_*() functions should leave *offset being the offset in 'words'
- * to the last character processed.
- */
-
-static int
-parse_backslash (char **word, size_t *word_length, size_t *max_length,
-		 const char *words, size_t *offset)
-{
-  /* We are poised _at_ a backslash, not in quotes */
-
-  switch (words[1 + *offset])
-    {
-    case 0:
-      /* Backslash is last character of input words */
-      return WRDE_SYNTAX;
-
-    case '\n':
-      ++(*offset);
-      break;
-
-    default:
-      *word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
-      if (*word == NULL)
-	return WRDE_NOSPACE;
-
-      ++(*offset);
-      break;
-    }
-
-  return 0;
-}
-
-static int
-parse_qtd_backslash (char **word, size_t *word_length, size_t *max_length,
-		     const char *words, size_t *offset)
-{
-  /* We are poised _at_ a backslash, inside quotes */
-
-  switch (words[1 + *offset])
-    {
-    case 0:
-      /* Backslash is last character of input words */
-      return WRDE_SYNTAX;
-
-    case '\n':
-      ++(*offset);
-      break;
-
-    case '$':
-    case '`':
-    case '"':
-    case '\\':
-      *word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
-      if (*word == NULL)
-	return WRDE_NOSPACE;
-
-      ++(*offset);
-      break;
-
-    default:
-      *word = w_addchar (*word, word_length, max_length, words[*offset]);
-      if (*word != NULL)
-	*word = w_addchar (*word, word_length, max_length, words[1 + *offset]);
-
-      if (*word == NULL)
-	return WRDE_NOSPACE;
-
-      ++(*offset);
-      break;
-    }
-
-  return 0;
-}
-
-static int
-parse_tilde (char **word, size_t *word_length, size_t *max_length,
-	     const char *words, size_t *offset, size_t wordc)
-{
-  /* We are poised _at_ a tilde */
-  size_t i;
-
-  if (*word_length != 0)
-    {
-      if (!((*word)[*word_length - 1] == '=' && wordc == 0))
-	{
-	  if (!((*word)[*word_length - 1] == ':'
-		&& strchr (*word, '=') && wordc == 0))
-	    {
-	      *word = w_addchar (*word, word_length, max_length, '~');
-	      return *word ? 0 : WRDE_NOSPACE;
-	    }
-	}
-    }
-
-  for (i = 1 + *offset; words[i]; i++)
-    {
-      if (words[i] == ':' || words[i] == '/' || words[i] == ' ' ||
-	  words[i] == '\t' || words[i] == 0 )
-	break;
-
-      if (words[i] == '\\')
-	{
-	  *word = w_addchar (*word, word_length, max_length, '~');
-	  return *word ? 0 : WRDE_NOSPACE;
-	}
-    }
-
-  if (i == 1 + *offset)
-    {
-      /* Tilde appears on its own */
-      uid_t uid;
-      struct passwd pwd, *tpwd;
-      int buflen = 1000;
-      char* home;
-      char* buffer;
-      int result;
-
-      /* POSIX.2 says ~ expands to $HOME and if HOME is unset the
-	 results are unspecified.  We do a lookup on the uid if
-	 HOME is unset. */
-
-      home = getenv ("HOME");
-      if (home != NULL)
-	{
-	  *word = w_addstr (*word, word_length, max_length, home);
-	  if (*word == NULL)
-	    return WRDE_NOSPACE;
-	}
-      else
-	{
-	  uid = getuid ();
-	  buffer = alloca (buflen);
-
-	  while ((result = getpwuid_r (uid, &pwd, buffer, buflen, &tpwd)) != 0
-		 && errno == ERANGE)
-	    {
-	      buflen += 1000;
-	      buffer = alloca (buflen);
-	    }
-
-	  if (result == 0 && tpwd != NULL && pwd.pw_dir != NULL)
-	    {
-	      *word = w_addstr (*word, word_length, max_length, pwd.pw_dir);
-	      if (*word == NULL)
-		return WRDE_NOSPACE;
-	    }
-	  else
-	    {
-	      *word = w_addchar (*word, word_length, max_length, '~');
-	      if (*word == NULL)
-		return WRDE_NOSPACE;
-	    }
-	}
-    }
-  else
-    {
-      /* Look up user name in database to get home directory */
-      char *user = strndup (&words[1 + *offset], i - (1 + *offset));
-      struct passwd pwd, *tpwd;
-      int buflen = 1000;
-      char* buffer = alloca (buflen);
-      int result;
-
-      while ((result = getpwnam_r (user, &pwd, buffer, buflen, &tpwd)) != 0
-	     && errno == ERANGE)
-	{
-	  buflen += 1000;
-	  buffer = alloca (buflen);
-	}
-
-      if (result == 0 && tpwd != NULL && pwd.pw_dir)
-	*word = w_addstr (*word, word_length, max_length, pwd.pw_dir);
-      else
-	{
-	  /* (invalid login name) */
-	  *word = w_addchar (*word, word_length, max_length, '~');
-	  if (*word != NULL)
-	    *word = w_addstr (*word, word_length, max_length, user);
-	}
-
-      *offset = i - 1;
-    }
-  return *word ? 0 : WRDE_NOSPACE;
-}
-
-
-static int
-do_parse_glob (const char *glob_word, char **word, size_t *word_length,
-	       size_t *max_length, wordexp_t *pwordexp, const char *ifs,
-	       const char *ifs_white)
-{
-  int error;
-  int match;
-  glob_t globbuf;
-
-  error = glob (glob_word, GLOB_NOCHECK, NULL, &globbuf);
-
-  if (error != 0)
-    {
-      /* We can only run into memory problems.  */
-      assert (error == GLOB_NOSPACE);
-      return WRDE_NOSPACE;
-    }
-
-  if (ifs && !*ifs)
-    {
-      /* No field splitting allowed. */
-      assert (globbuf.gl_pathv[0] != NULL);
-      *word = w_addstr (*word, word_length, max_length, globbuf.gl_pathv[0]);
-      for (match = 1; match < globbuf.gl_pathc && *word != NULL; ++match)
-	{
-	  *word = w_addchar (*word, word_length, max_length, ' ');
-	  if (*word != NULL)
-	    *word = w_addstr (*word, word_length, max_length,
-			      globbuf.gl_pathv[match]);
-	}
-
-      globfree (&globbuf);
-      return *word ? 0 : WRDE_NOSPACE;
-    }
-
-  assert (ifs == NULL || *ifs != '\0');
-  if (*word != NULL)
-    {
-      free (*word);
-      *word = w_newword (word_length, max_length);
-    }
-
-  for (match = 0; match < globbuf.gl_pathc; ++match)
-    {
-      char *matching_word = strdup (globbuf.gl_pathv[match]);
-      if (matching_word == NULL || w_addword (pwordexp, matching_word))
-	{
-	  globfree (&globbuf);
-	  return WRDE_NOSPACE;
-	}
-    }
-
-  globfree (&globbuf);
-  return 0;
-}
-
-static int
-parse_glob (char **word, size_t *word_length, size_t *max_length,
-	    const char *words, size_t *offset, int flags,
-	    wordexp_t *pwordexp, const char *ifs, const char *ifs_white)
-{
-  /* We are poised just after a '*', a '[' or a '?'. */
-  int error = WRDE_NOSPACE;
-  int quoted = 0; /* 1 if singly-quoted, 2 if doubly */
-  int i;
-  wordexp_t glob_list; /* List of words to glob */
-
-  glob_list.we_wordc = 0;
-  glob_list.we_wordv = NULL;
-  glob_list.we_offs = 0;
-  for (; words[*offset] != '\0'; ++*offset)
-    {
-      if ((ifs && strchr (ifs, words[*offset])) ||
-	  (!ifs && strchr (" \t\n", words[*offset])))
-	/* Reached IFS */
-	break;
-
-      /* Sort out quoting */
-      if (words[*offset] == '\'')
-	{
-	  if (quoted == 0)
-	    {
-	      quoted = 1;
-	      continue;
-	    }
-	  else if (quoted == 1)
-	    {
-	      quoted = 0;
-	      continue;
-	    }
-	}
-      else if (words[*offset] == '"')
-	{
-	  if (quoted == 0)
-	    {
-	      quoted = 2;
-	      continue;
-	    }
-	  else if (quoted == 2)
-	    {
-	      quoted = 0;
-	      continue;
-	    }
-	}
-
-      /* Sort out other special characters */
-      if (quoted != 1 && words[*offset] == '$')
-	{
-	  error = parse_dollars (word, word_length, max_length, words,
-				 offset, flags, &glob_list, ifs, ifs_white,
-				 quoted == 2);
-	  if (error)
-	    goto tidy_up;
-
-	  continue;
-	}
-      else if (words[*offset] == '\\')
-	{
-	  if (quoted)
-	    error = parse_qtd_backslash (word, word_length, max_length,
-					 words, offset);
-	  else
-	    error = parse_backslash (word, word_length, max_length,
-				     words, offset);
-
-	  if (error)
-	    goto tidy_up;
-
-	  continue;
-	}
-
-      *word = w_addchar (*word, word_length, max_length, words[*offset]);
-      if (*word == NULL)
-	goto tidy_up;
-    }
-
-  /* Don't forget to re-parse the character we stopped at. */
-  --*offset;
-
-  /* Glob the words */
-  error = w_addword (&glob_list, *word);
-  *word = w_newword (word_length, max_length);
-  for (i = 0; error == 0 && i < glob_list.we_wordc; i++)
-    error = do_parse_glob (glob_list.we_wordv[i], word, word_length,
-			   max_length, pwordexp, ifs, ifs_white);
-
-  /* Now tidy up */
-tidy_up:
-  wordfree (&glob_list);
-  return error;
-}
-
-static int
-parse_squote (char **word, size_t *word_length, size_t *max_length,
-	      const char *words, size_t *offset)
-{
-  /* We are poised just after a single quote */
-  for (; words[*offset]; ++(*offset))
-    {
-      if (words[*offset] != '\'')
-	{
-	  *word = w_addchar (*word, word_length, max_length, words[*offset]);
-	  if (*word == NULL)
-	    return WRDE_NOSPACE;
-	}
-      else return 0;
-    }
-
-  /* Unterminated string */
-  return WRDE_SYNTAX;
-}
-
-/* Functions to evaluate an arithmetic expression */
-static int
-eval_expr_val (char **expr, long int *result)
-{
-  int sgn = +1;
-  char *digit;
-
-  /* Skip white space */
-  for (digit = *expr; digit && *digit && isspace (*digit); ++digit);
-
-  switch (*digit)
-    {
-    case '(':
-
-      /* Scan for closing paren */
-      for (++digit; **expr && **expr != ')'; ++(*expr));
-
-      /* Is there one? */
-      if (!**expr)
-	return WRDE_SYNTAX;
-
-      *(*expr)++ = 0;
-
-      if (eval_expr (digit, result))
-	return WRDE_SYNTAX;
-
-      return 0;
-
-    case '+':	/* Positive value */
-      ++digit;
-      break;
-
-    case '-':	/* Negative value */
-      ++digit;
-      sgn = -1;
-      break;
-
-    default:
-      if (!isdigit (*digit))
-	return WRDE_SYNTAX;
-    }
-
-  *result = 0;
-  for (; *digit && isdigit (*digit); ++digit)
-    *result = (*result * 10) + (*digit - '0');
-
-  *expr = digit;
-  *result *= sgn;
-  return 0;
-}
-
-static int
-eval_expr_multdiv (char **expr, long int *result)
-{
-  long int arg;
-
-  /* Read a Value */
-  if (eval_expr_val (expr, result) != 0)
-    return WRDE_SYNTAX;
-
-  while (**expr)
-    {
-      /* Skip white space */
-      for (; *expr && **expr && isspace (**expr); ++(*expr));
-
-      if (**expr == '*')
-	{
-	  ++(*expr);
-	  if (eval_expr_val (expr, &arg) != 0)
-	    return WRDE_SYNTAX;
-
-	  *result *= arg;
-	}
-      else if (**expr == '/')
-	{
-	  ++(*expr);
-	  if (eval_expr_val (expr, &arg) != 0)
-	    return WRDE_SYNTAX;
-
-	  *result /= arg;
-	}
-      else break;
-    }
-
-  return 0;
-}
-
-static int
-eval_expr (char *expr, long int *result)
-{
-  long int arg;
-
-  /* Read a Multdiv */
-  if (eval_expr_multdiv (&expr, result) != 0)
-    return WRDE_SYNTAX;
-
-  while (*expr)
-    {
-      /* Skip white space */
-      for (; expr && *expr && isspace (*expr); ++expr);
-
-      if (*expr == '+')
-	{
-	  ++expr;
-	  if (eval_expr_multdiv (&expr, &arg) != 0)
-	    return WRDE_SYNTAX;
-
-	  *result += arg;
-	}
-      else if (*expr == '-')
-	{
-	  ++expr;
-	  if (eval_expr_multdiv (&expr, &arg) != 0)
-	    return WRDE_SYNTAX;
-
-	  *result -= arg;
-	}
-      else break;
-    }
-
-  return 0;
-}
-
-static int
-parse_arith (char **word, size_t *word_length, size_t *max_length,
-	     const char *words, size_t *offset, int flags, int bracket)
-{
-  /* We are poised just after "$((" or "$[" */
-  int error;
-  int paren_depth = 1;
-  size_t expr_length;
-  size_t expr_maxlen;
-  char *expr;
-
-  expr = w_newword (&expr_length, &expr_maxlen);
-  for (; words[*offset]; ++(*offset))
-    {
-      switch (words[*offset])
-	{
-	case '$':
-	  error = parse_dollars (&expr, &expr_length, &expr_maxlen,
-				 words, offset, flags, NULL, NULL, NULL, 1);
-	  /* The ``1'' here is to tell parse_dollars not to
-	   * split the fields.
-	   */
-	  if (error)
-	    {
-	      free (expr);
-	      return error;
-	    }
-	  break;
-
-	case '`':
-	  (*offset)++;
-	  error = parse_backtick (&expr, &expr_length, &expr_maxlen,
-				  words, offset, flags, NULL, NULL, NULL);
-	  /* The first NULL here is to tell parse_backtick not to
-	   * split the fields.
-	   */
-	  if (error)
-	    {
-	      free (expr);
-	      return error;
-	    }
-	  break;
-
-	case '\\':
-	  error = parse_qtd_backslash (&expr, &expr_length, &expr_maxlen,
-				       words, offset);
-	  if (error)
-	    {
-	      free (expr);
-	      return error;
-	    }
-	  /* I think that a backslash within an
-	   * arithmetic expansion is bound to
-	   * cause an error sooner or later anyway though.
-	   */
-	  break;
-
-	case ')':
-	  if (--paren_depth == 0)
-	    {
-	      char result[21];	/* 21 = ceil(log10(2^64)) + 1 */
-	      long int numresult = 0;
-	      long long int convertme;
-
-	      if (bracket || words[1 + *offset] != ')')
-		{
-		  free (expr);
-		  return WRDE_SYNTAX;
-		}
-
-	      ++(*offset);
-
-	      /* Go - evaluate. */
-	      if (*expr && eval_expr (expr, &numresult) != 0)
-		{
-		  free (expr);
-		  return WRDE_SYNTAX;
-		}
-
-	      if (numresult < 0)
-		{
-		  convertme = -numresult;
-		  *word = w_addchar (*word, word_length, max_length, '-');
-		  if (!*word)
-		    {
-		      free (expr);
-		      return WRDE_NOSPACE;
-		    }
-		}
-	      else
-		convertme = numresult;
-
-	      result[20] = '\0';
-	      *word = w_addstr (*word, word_length, max_length,
-				itoa (convertme, &result[20], 10, 0));
-	      free (expr);
-	      return *word ? 0 : WRDE_NOSPACE;
-	    }
-	  expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]);
-	  if (expr == NULL)
-	    return WRDE_NOSPACE;
-
-	  break;
-
-	case ']':
-	  if (bracket && paren_depth == 1)
-	    {
-	      char result[21];	/* 21 = ceil(log10(2^64)) + 1 */
-	      long int numresult = 0;
-
-	      /* Go - evaluate. */
-	      if (*expr && eval_expr (expr, &numresult) != 0)
-		{
-		  free (expr);
-		  return WRDE_SYNTAX;
-		}
-
-	      result[20] = '\0';
-	      *word = w_addstr (*word, word_length, max_length,
-				itoa_word (numresult, &result[20], 10, 0));
-	      free (expr);
-	      return *word ? 0 : WRDE_NOSPACE;
-	    }
-
-	  free (expr);
-	  return WRDE_SYNTAX;
-
-	case '\n':
-	case ';':
-	case '{':
-	case '}':
-	  free (expr);
-	  return WRDE_BADCHAR;
-
-	case '(':
-	  ++paren_depth;
-	default:
-	  expr = w_addchar (expr, &expr_length, &expr_maxlen, words[*offset]);
-	  if (expr == NULL)
-	    return WRDE_NOSPACE;
-	}
-    }
-
-  /* Premature end */
-  free (expr);
-  return WRDE_SYNTAX;
-}
-
-/* Function called by child process in exec_comm() */
-static void
-exec_comm_child (char *comm, int *fildes, int showerr, int noexec)
-{
-  const char *args[4] = { _PATH_BSHELL, "-c", comm, NULL };
-
-  /* Execute the command, or just check syntax? */
-  if (noexec)
-    args[1] = "-nc";
-
-  /* Redirect output.  */
-  dup2 (fildes[1], 1);
-  close (fildes[1]);
-
-  /* Redirect stderr to /dev/null if we have to.  */
-  if (showerr == 0)
-    {
-      int fd;
-      close (2);
-      fd = open (_PATH_DEVNULL, O_WRONLY);
-      if (fd >= 0 && fd != 2)
-	{
-	  dup2 (fd, 2);
-	  close (fd);
-	}
-    }
-
-  /* Make sure the subshell doesn't field-split on our behalf. */
-  unsetenv ("IFS");
-
-  close (fildes[0]);
-  execve (_PATH_BSHELL, (char *const *) args, __environ);
-
-  /* Bad.  What now?  */
-  abort ();
-}
-
-/* Function to execute a command and retrieve the results */
-/* pwordexp contains NULL if field-splitting is forbidden */
-static int
-exec_comm (char *comm, char **word, size_t *word_length, size_t *max_length,
-	   int flags, wordexp_t *pwordexp, const char *ifs,
-	   const char *ifs_white)
-{
-  int fildes[2];
-  int bufsize = 128;
-  int buflen;
-  int i;
-  int status = 0;
-  size_t maxnewlines = 0;
-  char *buffer;
-  pid_t pid;
-
-  /* Don't fork() unless necessary */
-  if (!comm || !*comm)
-    return 0;
-
-  if (pipe (fildes))
-    /* Bad */
-    return WRDE_NOSPACE;
-
-  if ((pid = fork ()) < 0)
-    {
-      /* Bad */
-      close (fildes[0]);
-      close (fildes[1]);
-      return WRDE_NOSPACE;
-    }
-
-  if (pid == 0)
-    exec_comm_child(comm, fildes, (flags & WRDE_SHOWERR), 0);
-
-  /* Parent */
-
-  close (fildes[1]);
-  buffer = alloca (bufsize);
-
-  if (!pwordexp)
-    /* Quoted - no field splitting */
-    {
-      while (1)
-	{
-	  if ((buflen = __read (fildes[0], buffer, bufsize)) < 1)
-	    {
-	      if (waitpid (pid, &status, WNOHANG) == 0)
-		continue;
-	      if ((buflen = __read (fildes[0], buffer, bufsize)) < 1)
-		break;
-	    }
-
-	  maxnewlines += buflen;
-
-	  *word = w_addmem (*word, word_length, max_length, buffer, buflen);
-	  if (*word == NULL)
-	    goto no_space;
-	}
-    }
-  else
-    /* Not quoted - split fields */
-    {
-      int copying = 0;
-      /* 'copying' is:
-       *  0 when searching for first character in a field not IFS white space
-       *  1 when copying the text of a field
-       *  2 when searching for possible non-whitespace IFS
-       *  3 when searching for non-newline after copying field
-       */
-
-      while (1)
-	{
-	  if ((buflen = __read (fildes[0], buffer, bufsize)) < 1)
-	    {
-	      if (waitpid (pid, &status, WNOHANG) == 0)
-		continue;
-	      if ((buflen = __read (fildes[0], buffer, bufsize)) < 1)
-		break;
-	    }
-
-	  for (i = 0; i < buflen; ++i)
-	    {
-	      if (strchr (ifs, buffer[i]) != NULL)
-		{
-		  /* Current character is IFS */
-		  if (strchr (ifs_white, buffer[i]) == NULL)
-		    {
-		      /* Current character is IFS but not whitespace */
-		      if (copying == 2)
-			{
-			  /*            current character
-			   *                   |
-			   *                   V
-			   * eg: text<space><comma><space>moretext
-			   *
-			   * So, strip whitespace IFS (like at the start)
-			   */
-			  copying = 0;
-			  continue;
-			}
-
-		      copying = 0;
-		      /* fall through and delimit field.. */
-		    }
-		  else
-		    {
-		      if (buffer[i] == '\n')
-			{
-			  /* Current character is (IFS) newline */
-
-			  /* If copying a field, this is the end of it,
-			     but maybe all that's left is trailing newlines.
-			     So start searching for a non-newline. */
-			  if (copying == 1)
-			    copying = 3;
-
-			  continue;
-			}
-		      else
-			{
-			  /* Current character is IFS white space, but
-			     not a newline */
-
-			  /* If not either copying a field or searching
-			     for non-newline after a field, ignore it */
-			  if (copying != 1 && copying != 3)
-			    continue;
-
-			  /* End of field (search for non-ws IFS afterwards) */
-			  copying = 2;
-			}
-		    }
-
-		  /* First IFS white space (non-newline), or IFS non-whitespace.
-		   * Delimit the field.  Nulls are converted by w_addword. */
-		  if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
-		    goto no_space;
-
-		  *word = w_newword (word_length, max_length);
-
-		  maxnewlines = 0;
-		  /* fall back round the loop.. */
-		}
-	      else
-		{
-		  /* Not IFS character */
-
-		  if (copying == 3)
-		    {
-		      /* Nothing but (IFS) newlines since the last field,
-		         so delimit it here before starting new word */
-		      if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
-			goto no_space;
-
-		      *word = w_newword (word_length, max_length);
-		    }
-
-		  copying = 1;
-
-		  if (buffer[i] == '\n') /* happens if newline not in IFS */
-		    maxnewlines++;
-		  else
-		    maxnewlines = 0;
-
-		  *word = w_addchar (*word, word_length, max_length,
-				     buffer[i]);
-		  if (*word == NULL)
-		    goto no_space;
-		}
-	    }
-	}
-    }
-
-  /* Chop off trailing newlines (required by POSIX.2)  */
-  /* Ensure we don't go back further than the beginning of the
-     substitution (i.e. remove maxnewlines bytes at most) */
-  while (maxnewlines-- != 0 &&
-         *word_length > 0 && (*word)[*word_length - 1] == '\n')
-    {
-      (*word)[--*word_length] = '\0';
-
-      /* If the last word was entirely newlines, turn it into a new word
-       * which can be ignored if there's nothing following it. */
-      if (*word_length == 0)
-	{
-	  free (*word);
-	  *word = w_newword (word_length, max_length);
-	  break;
-	}
-    }
-
-  close (fildes[0]);
-
-  /* Check for syntax error (re-execute but with "-n" flag) */
-  if (buflen < 1 && status != 0)
-    {
-      if ((pid = fork ()) < 0)
-	{
-	  /* Bad */
-	  return WRDE_NOSPACE;
-	}
-
-      if (pid == 0)
-	{
-          fildes[0] = fildes[1] = -1;
-	  exec_comm_child(comm, fildes, 0, 1);
-	}
-      
-      if (waitpid (pid, &status, 0) == pid && status != 0)
-	return WRDE_SYNTAX;
-    }
-
-  return 0;
-
-no_space:
-  kill (pid, SIGKILL);
-  waitpid (pid, NULL, 0);
-  close (fildes[0]);
-  return WRDE_NOSPACE;
-}
-
-static int
-parse_comm (char **word, size_t *word_length, size_t *max_length,
-	    const char *words, size_t *offset, int flags, wordexp_t *pwordexp,
-	    const char *ifs, const char *ifs_white)
-{
-  /* We are poised just after "$(" */
-  int paren_depth = 1;
-  int error = 0;
-  int quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */
-  size_t comm_length;
-  size_t comm_maxlen;
-  char *comm = w_newword (&comm_length, &comm_maxlen);
-
-  for (; words[*offset]; ++(*offset))
-    {
-      switch (words[*offset])
-	{
-	case '\'':
-	  if (quoted == 0)
-	    quoted = 1;
-	  else if (quoted == 1)
-	    quoted = 0;
-
-	  break;
-
-	case '"':
-	  if (quoted == 0)
-	    quoted = 2;
-	  else if (quoted == 2)
-	    quoted = 0;
-
-	  break;
-
-	case ')':
-	  if (!quoted && --paren_depth == 0)
-	    {
-	      /* Go -- give script to the shell */
-	      if (comm)
-		{
-		  error = exec_comm (comm, word, word_length, max_length,
-				     flags, pwordexp, ifs, ifs_white);
-		  free (comm);
-		}
-
-	      return error;
-	    }
-
-	  /* This is just part of the script */
-	  break;
-
-	case '(':
-	  if (!quoted)
-	    ++paren_depth;
-	}
-
-      comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]);
-      if (comm == NULL)
-	return WRDE_NOSPACE;
-    }
-
-  /* Premature end */
-  if (comm)
-    free (comm);
-
-  return WRDE_SYNTAX;
-}
-
-static int
-parse_param (char **word, size_t *word_length, size_t *max_length,
-	     const char *words, size_t *offset, int flags, wordexp_t *pwordexp,
-	     const char *ifs, const char *ifs_white, int quoted)
-{
-  /* We are poised just after "$" */
-  enum action
-  {
-    ACT_NONE,
-    ACT_RP_SHORT_LEFT = '#',
-    ACT_RP_LONG_LEFT = 'L',
-    ACT_RP_SHORT_RIGHT = '%',
-    ACT_RP_LONG_RIGHT = 'R',
-    ACT_NULL_ERROR = '?',
-    ACT_NULL_SUBST = '-',
-    ACT_NONNULL_SUBST = '+',
-    ACT_NULL_ASSIGN = '='
-  };
-  size_t env_length;
-  size_t env_maxlen;
-  size_t pat_length;
-  size_t pat_maxlen;
-  size_t start = *offset;
-  char *env;
-  char *pattern;
-  char *value = NULL;
-  enum action action = ACT_NONE;
-  int depth = 0;
-  int colon_seen = 0;
-  int seen_hash = 0;
-  int free_value = 0;
-  int pattern_is_quoted = 0; /* 1 for singly-quoted, 2 for doubly-quoted */
-  int error;
-  int special = 0;
-  char buffer[21];
-  int brace = words[*offset] == '{';
-
-  env = w_newword (&env_length, &env_maxlen);
-  pattern = w_newword (&pat_length, &pat_maxlen);
-
-  if (brace)
-    ++*offset;
-
-  /* First collect the parameter name. */
-
-  if (words[*offset] == '#')
-    {
-      seen_hash = 1;
-      if (!brace)
-	goto envsubst;
-      ++*offset;
-    }
-
-  if (isalpha (words[*offset]) || words[*offset] == '_')
-    {
-      /* Normal parameter name. */
-      do
-	{
-	  env = w_addchar (env, &env_length, &env_maxlen,
-			   words[*offset]);
-	  if (env == NULL)
-	    goto no_space;
-	}
-      while (isalnum (words[++*offset]) || words[*offset] == '_');
-    }
-  else if (isdigit (words[*offset]))
-    {
-      /* Numeric parameter name. */
-      special = 1;
-      do
-	{
-	  env = w_addchar (env, &env_length, &env_maxlen,
-			   words[*offset]);
-	  if (env == NULL)
-	    goto no_space;
-	  if (!brace)
-	    goto envsubst;
-	}
-      while (isdigit(words[++*offset]));
-    }
-  else if (strchr ("*@$", words[*offset]) != NULL)
-    {
-      /* Special parameter. */
-      special = 1;
-      env = w_addchar (env, &env_length, &env_maxlen,
-		       words[*offset]);
-      if (env == NULL)
-	goto no_space;
-      ++*offset;
-    }
-  else
-    {
-      if (brace)
-	goto syntax;
-    }
-
-  if (brace)
-    {
-      /* Check for special action to be applied to the value. */
-      switch (words[*offset])
-	{
-	case '}':
-	  /* Evaluate. */
-	  goto envsubst;
-
-	case '#':
-	  action = ACT_RP_SHORT_LEFT;
-	  if (words[1 + *offset] == '#')
-	    {
-	      ++*offset;
-	      action = ACT_RP_LONG_LEFT;
-	    }
-	  break;
-
-	case '%':
-	  action = ACT_RP_SHORT_RIGHT;
-	  if (words[1 + *offset] == '%')
-	    {
-	      ++*offset;
-	      action = ACT_RP_LONG_RIGHT;
-	    }
-	  break;
-
-	case ':':
-	  if (strchr ("-=?+", words[1 + *offset]) == NULL)
-	    goto syntax;
-
-	  colon_seen = 1;
-	  action = words[++*offset];
-	  break;
-
-	case '-':
-	case '=':
-	case '?':
-	case '+':
-	  action = words[*offset];
-	  break;
-
-	default:
-	  goto syntax;
-	}
-
-      /* Now collect the pattern, but don't expand it yet. */
-      ++*offset;
-      for (; words[*offset]; ++(*offset))
-	{
-	  switch (words[*offset])
-	    {
-	    case '{':
-	      if (!pattern_is_quoted)
-		++depth;
-	      break;
-
-	    case '}':
-	      if (!pattern_is_quoted)
-		{
-		  if (depth == 0)
-		    goto envsubst;
-		  --depth;
-		}
-	      break;
-
-	    case '\\':
-	      if (pattern_is_quoted)
-		/* Quoted; treat as normal character. */
-		break;
-
-	      /* Otherwise, it's an escape: next character is literal. */
-	      if (words[++*offset] == '\0')
-		goto syntax;
-
-	      pattern = w_addchar (pattern, &pat_length, &pat_maxlen, '\\');
-	      if (pattern == NULL)
-		goto no_space;
-
-	      break;
-
-	    case '\'':
-	      if (pattern_is_quoted == 0)
-		pattern_is_quoted = 1;
-	      else if (pattern_is_quoted == 1)
-		pattern_is_quoted = 0;
-
-	      break;
-
-	    case '"':
-	      if (pattern_is_quoted == 0)
-		pattern_is_quoted = 2;
-	      else if (pattern_is_quoted == 2)
-		pattern_is_quoted = 0;
-
-	      break;
-	    }
-
-	  pattern = w_addchar (pattern, &pat_length, &pat_maxlen,
-			       words[*offset]);
-	  if (pattern == NULL)
-	    goto no_space;
-	}
-    }
-
-  /* End of input string -- remember to reparse the character that we
-   * stopped at.  */
-  --(*offset);
-
-envsubst:
-  if (words[start] == '{' && words[*offset] != '}')
-    goto syntax;
-
-  if (env == NULL)
-    {
-      if (seen_hash)
-	{
-	  /* $# expands to the number of positional parameters */
-	  buffer[20] = '\0';
-	  value = itoa_word (__libc_argc - 1, &buffer[20], 10, 0);
-	  seen_hash = 0;
-	}
-      else
-	{
-	  /* Just $ on its own */
-	  *offset = start - 1;
-	  *word = w_addchar (*word, word_length, max_length, '$');
-	  return *word ? 0 : WRDE_NOSPACE;
-	}
-    }
-  /* Is it a numeric parameter? */
-  else if (isdigit (env[0]))
-    {
-      int n = atoi (env);
-
-      if (n >= __libc_argc)
-	/* Substitute NULL. */
-	value = NULL;
-      else
-	/* Replace with appropriate positional parameter. */
-	value = __libc_argv[n];
-    }
-  /* Is it a special parameter? */
-  else if (special)
-    {
-      /* Is it `$$'? */
-      if (*env == '$')
-	{
-	  buffer[20] = '\0';
-	  value = itoa_word (__getpid (), &buffer[20], 10, 0);
-	}
-      /* Is it `${#*}' or `${#@}'? */
-      else if ((*env == '*' || *env == '@') && seen_hash)
-	{
-	  buffer[20] = '\0';
-	  value = itoa_word (__libc_argc > 0 ? __libc_argc - 1 : 0,
-			      &buffer[20], 10, 0);
-	  *word = w_addstr (*word, word_length, max_length, value);
-	  free (env);
-	  if (pattern)
-	    free (pattern);
-	  return *word ? 0 : WRDE_NOSPACE;
-	}
-      /* Is it `$*' or `$@' (unquoted) ? */
-      else if (*env == '*' || (*env == '@' && !quoted))
-	{
-	  size_t plist_len = 0;
-	  int p;
-	  char *end;
-
-	  /* Build up value parameter by parameter (copy them) */
-	  for (p = 1; __libc_argv[p]; ++p)
-	    plist_len += strlen (__libc_argv[p]) + 1; /* for space */
-	  value = malloc (plist_len);
-	  if (value == NULL)
-	    goto no_space;
-	  end = value;
-	  *end = 0;
-	  for (p = 1; __libc_argv[p]; ++p)
-	    {
-	      if (p > 1)
-		*end++ = ' ';
-	      end = __stpcpy (end, __libc_argv[p]);
-	    }
-
-	  free_value = 1;
-	}
-      else
-	{
-	  /* Must be a quoted `$@' */
-	  assert (*env == '@' && quoted);
-
-	  /* Each parameter is a separate word ("$@") */
-	  if (__libc_argc == 2)
-	    value = __libc_argv[1];
-	  else if (__libc_argc > 2)
-	    {
-	      int p;
-
-	      /* Append first parameter to current word. */
-	      value = w_addstr (*word, word_length, max_length,
-				__libc_argv[1]);
-	      if (value == NULL || w_addword (pwordexp, value))
-		goto no_space;
-
-	      for (p = 2; __libc_argv[p + 1]; p++)
-		{
-		  char *newword = strdup (__libc_argv[p]);
-		  if (newword == NULL || w_addword (pwordexp, newword))
-		    goto no_space;
-		}
-
-	      /* Start a new word with the last parameter. */
-	      *word = w_newword (word_length, max_length);
-	      value = __libc_argv[p];
-	    }
-	  else
-	    {
-	      free (env);
-	      free (pattern);
-	      return 0;
-	    }
-	}
-    }
-  else
-    value = getenv (env);
-
-  if (value == NULL && (flags & WRDE_UNDEF))
-    {
-      /* Variable not defined. */
-      error = WRDE_BADVAL;
-      goto do_error;
-    }
-
-  if (action != ACT_NONE)
-    {
-      int expand_pattern = 0;
-
-      /* First, find out if we need to expand pattern (i.e. if we will
-       * use it). */
-      switch (action)
-	{
-	case ACT_RP_SHORT_LEFT:
-	case ACT_RP_LONG_LEFT:
-	case ACT_RP_SHORT_RIGHT:
-	case ACT_RP_LONG_RIGHT:
-	  /* Always expand for these. */
-	  expand_pattern = 1;
-	  break;
-
-	case ACT_NULL_ERROR:
-	case ACT_NULL_SUBST:
-	case ACT_NULL_ASSIGN:
-	  if (!value || (!*value && colon_seen))
-	    /* If param is unset, or set but null and a colon has been seen,
-	       the expansion of the pattern will be needed. */
-	    expand_pattern = 1;
-
-	  break;
-
-	case ACT_NONNULL_SUBST:
-	  /* Expansion of word will be needed if parameter is set and not null,
-	     or set null but no colon has been seen. */
-	  if (value && (*value || !colon_seen))
-	    expand_pattern = 1;
-
-	  break;
-
-	default:
-	  assert (! "Unrecognised action!");
-	}
-
-      if (expand_pattern)
-	{
-	  /* We need to perform tilde expansion, parameter expansion,
-             command substitution, and arithmetic expansion.  We also
-	     have to be a bit careful with wildcard characters, as
-	     pattern might be given to fnmatch soon.  To do this, we
-	     convert quotes to escapes. */
-
-	  char *expanded;
-	  size_t exp_len;
-	  size_t exp_maxl;
-	  char *p;
-	  int quoted = 0; /* 1: single quotes; 2: double */
-
-	  expanded = w_newword (&exp_len, &exp_maxl);
-	  for (p = pattern; p && *p; p++)
-	    {
-	      size_t offset;
-
-	      switch (*p)
-		{
-		case '"':
-		  if (quoted == 2)
-		    quoted = 0;
-		  else if (quoted == 0)
-		    quoted = 2;
-		  else break;
-
-		  continue;
-
-		case '\'':
-		  if (quoted == 1)
-		    quoted = 0;
-		  else if (quoted == 0)
-		    quoted = 1;
-		  else break;
-
-		  continue;
-
-		case '*':
-		case '?':
-		  if (quoted)
-		    {
-		      /* Convert quoted wildchar to escaped wildchar. */
-		      expanded = w_addchar (expanded, &exp_len,
-					    &exp_maxl, '\\');
-
-		      if (expanded == NULL)
-			goto no_space;
-		    }
-		  break;
-
-		case '$':
-		  offset = 0;
-		  error = parse_dollars (&expanded, &exp_len, &exp_maxl, p,
-					 &offset, flags, NULL, NULL, NULL, 1);
-		  if (error)
-		    {
-		      if (free_value)
-			free (value);
-
-		      if (expanded)
-			free (expanded);
-
-		      goto do_error;
-		    }
-
-		  p += offset;
-		  continue;
-
-		case '~':
-		  if (quoted || exp_len)
-		    break;
-
-		  offset = 0;
-		  error = parse_tilde (&expanded, &exp_len, &exp_maxl, p,
-				       &offset, 0);
-		  if (error)
-		    {
-		      if (free_value)
-			free (value);
-
-		      if (expanded)
-			free (expanded);
-
-		      goto do_error;
-		    }
-
-		  p += offset;
-		  continue;
-
-		case '\\':
-		  expanded = w_addchar (expanded, &exp_len, &exp_maxl, '\\');
-		  ++p;
-		  assert (*p); /* checked when extracted initially */
-		  if (expanded == NULL)
-		    goto no_space;
-		}
-
-	      expanded = w_addchar (expanded, &exp_len, &exp_maxl, *p);
-
-	      if (expanded == NULL)
-		goto no_space;
-	    }
-
-	  if (pattern)
-		  free (pattern);
-
-	  pattern = expanded;
-	}
-
-      switch (action)
-	{
-	case ACT_RP_SHORT_LEFT:
-	case ACT_RP_LONG_LEFT:
-	case ACT_RP_SHORT_RIGHT:
-	case ACT_RP_LONG_RIGHT:
-	  {
-	    char *p;
-	    char c;
-	    char *end;
-
-	    if (value == NULL || pattern == NULL || *pattern == '\0')
-	      break;
-
-	    end = value + strlen (value);
-
-	    switch (action)
-	      {
-	      case ACT_RP_SHORT_LEFT:
-		for (p = value; p <= end; ++p)
-		  {
-		    c = *p;
-		    *p = '\0';
-		    if (fnmatch (pattern, value, 0) != FNM_NOMATCH)
-		      {
-			*p = c;
-			if (free_value)
-			  {
-			    char *newval = strdup (p);
-			    if (newval == NULL)
-			      {
-				free (value);
-				goto no_space;
-			      }
-			    free (value);
-			    value = newval;
-			  }
-			else
-			  value = p;
-			break;
-		      }
-		    *p = c;
-		  }
-
-		break;
-
-	      case ACT_RP_LONG_LEFT:
-		for (p = end; p >= value; --p)
-		  {
-		    c = *p;
-		    *p = '\0';
-		    if (fnmatch (pattern, value, 0) != FNM_NOMATCH)
-		      {
-			*p = c;
-			if (free_value)
-			  {
-			    char *newval = strdup (p);
-			    if (newval == NULL)
-			      {
-				free (value);
-				goto no_space;
-			      }
-			    free (value);
-			    value = newval;
-			  }
-			else
-			  value = p;
-			break;
-		      }
-		    *p = c;
-		  }
-
-		break;
-
-	      case ACT_RP_SHORT_RIGHT:
-		for (p = end; p >= value; --p)
-		  {
-		    if (fnmatch (pattern, p, 0) != FNM_NOMATCH)
-		      {
-			char *newval;
-			newval = malloc (p - value + 1);
-
-			if (newval == NULL)
-			  {
-			    if (free_value)
-			      free (value);
-			    goto no_space;
-			  }
-
-			*(char *) mempcpy (newval, value, p - value) = '\0';
-			if (free_value)
-			  free (value);
-			value = newval;
-			free_value = 1;
-			break;
-		      }
-		  }
-
-		break;
-
-	      case ACT_RP_LONG_RIGHT:
-		for (p = value; p <= end; ++p)
-		  {
-		    if (fnmatch (pattern, p, 0) != FNM_NOMATCH)
-		      {
-			char *newval;
-			newval = malloc (p - value + 1);
-
-			if (newval == NULL)
-			  {
-			    if (free_value)
-			      free (value);
-			    goto no_space;
-			  }
-
-			*(char *) mempcpy (newval, value, p - value) = '\0';
-			if (free_value)
-			  free (value);
-			value = newval;
-			free_value = 1;
-			break;
-		      }
-		  }
-
-		break;
-
-	      default:
-		break;
-	      }
-
-	    break;
-	  }
-
-	case ACT_NULL_ERROR:
-	  if (value && *value)
-	    /* Substitute parameter */
-	    break;
-
-	  error = 0;
-	  if (!colon_seen && value)
-	    /* Substitute NULL */
-	    ;
-	  else if (*pattern)
-	    fprintf (stderr, "%s: %s\n", env, pattern);
-	  else
-	    {
-	      fprintf (stderr, "%s: parameter null or not set\n", env);
-	      error = WRDE_BADVAL;
-	    }
-
-	  if (free_value)
-	    free (value);
-	  goto do_error;
-
-	case ACT_NULL_SUBST:
-	  if (value && *value)
-	    /* Substitute parameter */
-	    break;
-
-	  if (free_value && value)
-	    free (value);
-
-	  if (!colon_seen && value)
-	    /* Substitute NULL */
-	    goto success;
-
-	  value = pattern ? strdup (pattern) : pattern;
-	  free_value = 1;
-
-	  if (pattern && !value)
-	    goto no_space;
-
-	  break;
-
-	case ACT_NONNULL_SUBST:
-	  if (value && (*value || !colon_seen))
-	    {
-	      if (free_value && value)
-		free (value);
-
-	      value = pattern ? strdup (pattern) : pattern;
-	      free_value = 1;
-
-	      if (pattern && !value)
-		goto no_space;
-
-	      break;
-	    }
-
-	  /* Substitute NULL */
-	  if (free_value)
-	    free (value);
-	  goto success;
-
-	case ACT_NULL_ASSIGN:
-	  if (value && *value)
-	    /* Substitute parameter */
-	    break;
-
-	  if (!colon_seen && value)
-	    {
-	      /* Substitute NULL */
-	      if (free_value)
-		free (value);
-	      goto success;
-	    }
-
-	  if (free_value && value)
-	    free (value);
-
-	  value = pattern ? strdup (pattern) : pattern;
-	  free_value = 1;
-
-	  if (pattern && !value)
-	    goto no_space;
-
-	  setenv (env, value, 1);
-	  break;
-
-	default:
-	  assert (! "Unrecognised action!");
-	}
-    }
-
-  free (env); env = NULL;
-  free (pattern); pattern = NULL;
-
-  if (seen_hash)
-    {
-      char param_length[21];
-      param_length[20] = '\0';
-      *word = w_addstr (*word, word_length, max_length,
-			itoa_word (value ? strlen (value) : 0,
-				    &param_length[20], 10, 0));
-      if (free_value)
-	{
-	  assert (value != NULL);
-	  free (value);
-	}
-
-      return *word ? 0 : WRDE_NOSPACE;
-    }
-
-  if (value == NULL)
-    return 0;
-
-  if (quoted || !pwordexp)
-    {
-      /* Quoted - no field split */
-      *word = w_addstr (*word, word_length, max_length, value);
-      if (free_value)
-	free (value);
-
-      return *word ? 0 : WRDE_NOSPACE;
-    }
-  else
-    {
-      /* Need to field-split */
-      char *value_copy = strdup (value); /* Don't modify value */
-      char *field_begin = value_copy;
-      int seen_nonws_ifs = 0;
-
-      if (free_value)
-	free (value);
-
-      if (value_copy == NULL)
-	goto no_space;
-
-      do
-	{
-	  char *field_end = field_begin;
-	  char *next_field;
-
-	  /* If this isn't the first field, start a new word */
-	  if (field_begin != value_copy)
-	    {
-	      if (w_addword (pwordexp, *word) == WRDE_NOSPACE)
-		{
-		  free (value_copy);
-		  goto no_space;
-		}
-
-	      *word = w_newword (word_length, max_length);
-	    }
-
-	  /* Skip IFS whitespace before the field */
-	  field_begin += strspn (field_begin, ifs_white);
-
-	  if (!seen_nonws_ifs && *field_begin == 0)
-	    /* Nothing but whitespace */
-	    break;
-
-	  /* Search for the end of the field */
-	  field_end = field_begin + strcspn (field_begin, ifs);
-
-	  /* Set up pointer to the character after end of field and
-             skip whitespace IFS after it. */
-	  next_field = field_end + strspn (field_end, ifs_white);
-
-	  /* Skip at most one non-whitespace IFS character after the field */
-	  seen_nonws_ifs = 0;
-	  if (*next_field && strchr (ifs, *next_field))
-	    {
-	      seen_nonws_ifs = 1;
-	      next_field++;
-	    }
-
-	  /* Null-terminate it */
-	  *field_end = 0;
-
-	  /* Tag a copy onto the current word */
-	  *word = w_addstr (*word, word_length, max_length, field_begin);
-
-	  if (*word == NULL && *field_begin != '\0')
-	    {
-	      free (value_copy);
-	      goto no_space;
-	    }
-
-	  field_begin = next_field;
-	}
-      while (seen_nonws_ifs || *field_begin);
-
-      free (value_copy);
-    }
-
-  return 0;
-
-success:
-  error = 0;
-  goto do_error;
-
-no_space:
-  error = WRDE_NOSPACE;
-  goto do_error;
-
-syntax:
-  error = WRDE_SYNTAX;
-
-do_error:
-  if (env)
-    free (env);
-
-  if (pattern)
-    free (pattern);
-
-  return error;
-}
-
-static int
-parse_dollars (char **word, size_t *word_length, size_t *max_length,
-	       const char *words, size_t *offset, int flags,
-	       wordexp_t *pwordexp, const char *ifs, const char *ifs_white,
-	       int quoted)
-{
-  /* We are poised _at_ "$" */
-  switch (words[1 + *offset])
-    {
-    case '"':
-    case '\'':
-    case 0:
-      *word = w_addchar (*word, word_length, max_length, '$');
-      return *word ? 0 : WRDE_NOSPACE;
-
-    case '(':
-      if (words[2 + *offset] == '(')
-	{
-	  /* Differentiate between $((1+3)) and $((echo);(ls)) */
-	  int i = 3 + *offset;
-	  int depth = 0;
-	  while (words[i] && !(depth == 0 && words[i] == ')'))
-	    {
-	      if (words[i] == '(')
-		++depth;
-	      else if (words[i] == ')')
-		--depth;
-
-	      ++i;
-	    }
-
-	  if (words[i] == ')' && words[i + 1] == ')')
-	    {
-	      (*offset) += 3;
-	      /* Call parse_arith -- 0 is for "no brackets" */
-	      return parse_arith (word, word_length, max_length, words, offset,
-				  flags, 0);
-	    }
-	}
-
-      if (flags & WRDE_NOCMD)
-	return WRDE_CMDSUB;
-
-      (*offset) += 2;
-      return parse_comm (word, word_length, max_length, words, offset, flags,
-			 quoted? NULL : pwordexp, ifs, ifs_white);
-
-    case '[':
-      (*offset) += 2;
-      /* Call parse_arith -- 1 is for "brackets" */
-      return parse_arith (word, word_length, max_length, words, offset, flags,
-			  1);
-
-    case '{':
-    default:
-      ++(*offset);	/* parse_param needs to know if "{" is there */
-      return parse_param (word, word_length, max_length, words, offset, flags,
-			   pwordexp, ifs, ifs_white, quoted);
-    }
-}
-
-static int
-parse_backtick (char **word, size_t *word_length, size_t *max_length,
-		const char *words, size_t *offset, int flags,
-		wordexp_t *pwordexp, const char *ifs, const char *ifs_white)
-{
-  /* We are poised just after "`" */
-  int error;
-  int squoting = 0;
-  size_t comm_length;
-  size_t comm_maxlen;
-  char *comm = w_newword (&comm_length, &comm_maxlen);
-
-  for (; words[*offset]; ++(*offset))
-    {
-      switch (words[*offset])
-	{
-	case '`':
-	  /* Go -- give the script to the shell */
-	  error = exec_comm (comm, word, word_length, max_length, flags,
-			     pwordexp, ifs, ifs_white);
-	  free (comm);
-	  return error;
-
-	case '\\':
-	  if (squoting)
-	    {
-	      error = parse_qtd_backslash (&comm, &comm_length, &comm_maxlen,
-					   words, offset);
-
-	      if (error)
-		{
-		  free (comm);
-		  return error;
-		}
-
-	      break;
-	    }
-
-	  ++(*offset);
-	  error = parse_backslash (&comm, &comm_length, &comm_maxlen, words,
-				   offset);
-
-	  if (error)
-	    {
-	      free (comm);
-	      return error;
-	    }
-
-	  break;
-
-	case '\'':
-	  squoting = 1 - squoting;
-	default:
-	  comm = w_addchar (comm, &comm_length, &comm_maxlen, words[*offset]);
-	  if (comm == NULL)
-	    return WRDE_NOSPACE;
-	}
-    }
-
-  /* Premature end */
-  free (comm);
-  return WRDE_SYNTAX;
-}
-
-static int
-parse_dquote (char **word, size_t *word_length, size_t *max_length,
-	      const char *words, size_t *offset, int flags,
-	      wordexp_t *pwordexp, const char * ifs, const char * ifs_white)
-{
-  /* We are poised just after a double-quote */
-  int error;
-
-  for (; words[*offset]; ++(*offset))
-    {
-      switch (words[*offset])
-	{
-	case '"':
-	  return 0;
-
-	case '$':
-	  error = parse_dollars (word, word_length, max_length, words, offset,
-				 flags, pwordexp, ifs, ifs_white, 1);
-	  /* The ``1'' here is to tell parse_dollars not to
-	   * split the fields.  It may need to, however ("$@").
-	   */
-	  if (error)
-	    return error;
-
-	  break;
-
-	case '`':
-	  if (flags & WRDE_NOCMD)
-	    return WRDE_CMDSUB;
-
-	  ++(*offset);
-	  error = parse_backtick (word, word_length, max_length, words,
-				  offset, flags, NULL, NULL, NULL);
-	  /* The first NULL here is to tell parse_backtick not to
-	   * split the fields.
-	   */
-	  if (error)
-	    return error;
-
-	  break;
-
-	case '\\':
-	  error = parse_qtd_backslash (word, word_length, max_length, words,
-				       offset);
-
-	  if (error)
-	    return error;
-
-	  break;
-
-	default:
-	  *word = w_addchar (*word, word_length, max_length, words[*offset]);
-	  if (*word == NULL)
-	    return WRDE_NOSPACE;
-	}
-    }
-
-  /* Unterminated string */
-  return WRDE_SYNTAX;
-}
-
-/*
- * wordfree() is to be called after pwordexp is finished with.
- */
-
-void
-wordfree (wordexp_t *pwordexp)
-{
-
-  /* wordexp can set pwordexp to NULL */
-  if (pwordexp && pwordexp->we_wordv)
-    {
-      char **wordv = pwordexp->we_wordv;
-
-      for (wordv += pwordexp->we_offs; *wordv; ++wordv)
-	free (*wordv);
-
-      free (pwordexp->we_wordv);
-      pwordexp->we_wordv = NULL;
-    }
-}
-
-/*
- * wordexp()
- */
-
-int
-wordexp (const char *words, wordexp_t *pwordexp, int flags)
-{
-  size_t words_offset;
-  size_t word_length;
-  size_t max_length;
-  char *word = w_newword (&word_length, &max_length);
-  int error;
-  char *ifs;
-  char ifs_white[4];
-  wordexp_t old_word = *pwordexp;
-
-  if (flags & WRDE_REUSE)
-    {
-      /* Minimal implementation of WRDE_REUSE for now */
-      wordfree (pwordexp);
-      old_word.we_wordv = NULL;
-    }
-
-  if ((flags & WRDE_APPEND) == 0)
-    {
-      pwordexp->we_wordc = 0;
-
-      if (flags & WRDE_DOOFFS)
-	{
-	  pwordexp->we_wordv = calloc (1 + pwordexp->we_offs, sizeof (char *));
-	  if (pwordexp->we_wordv == NULL)
-	    {
-	      error = WRDE_NOSPACE;
-	      goto do_error;
-	    }
-	}
-      else
-	{
-	  pwordexp->we_wordv = calloc (1, sizeof (char *));
-	  if (pwordexp->we_wordv == NULL)
-	    {
-	      error = WRDE_NOSPACE;
-	      goto do_error;
-	    }
-
-	  pwordexp->we_offs = 0;
-	}
-    }
-
-  /* Find out what the field separators are.
-   * There are two types: whitespace and non-whitespace.
-   */
-  ifs = getenv ("IFS");
-
-  if (!ifs)
-    /* IFS unset - use <space><tab><newline>. */
-    ifs = strcpy (ifs_white, " \t\n");
-  else
-    {
-      char *ifsch = ifs;
-      char *whch = ifs_white;
-
-      /* Start off with no whitespace IFS characters */
-      ifs_white[0] = '\0';
-
-      while (*ifsch != '\0')
-	{
-	  if ((*ifsch == ' ') || (*ifsch == '\t') || (*ifsch == '\n'))
-	    {
-	      /* Whitespace IFS.  See first whether it is already in our
-		 collection.  */
-	      char *runp = ifs_white;
-
-	      while (runp < whch && *runp != '\0' && *runp != *ifsch)
-		++runp;
-
-	      if (runp == whch)
-		*whch++ = *ifsch;
-	    }
-
-	  ++ifsch;
-	}
-      *whch = '\0';
-    }
-
-  for (words_offset = 0 ; words[words_offset] ; ++words_offset)
-    switch (words[words_offset])
-      {
-      case '\\':
-	error = parse_backslash (&word, &word_length, &max_length, words,
-				 &words_offset);
-
-	if (error)
-	  goto do_error;
-
-	break;
-
-      case '$':
-	error = parse_dollars (&word, &word_length, &max_length, words,
-			       &words_offset, flags, pwordexp, ifs, ifs_white,
-			       0);
-
-	if (error)
-	  goto do_error;
-
-	break;
-
-      case '`':
-	if (flags & WRDE_NOCMD)
-	  {
-	    error = WRDE_CMDSUB;
-	    goto do_error;
-	  }
-
-	++words_offset;
-	error = parse_backtick (&word, &word_length, &max_length, words,
-				&words_offset, flags, pwordexp, ifs,
-				ifs_white);
-
-	if (error)
-	  goto do_error;
-
-	break;
-
-      case '"':
-	++words_offset;
-	error = parse_dquote (&word, &word_length, &max_length, words,
-			      &words_offset, flags, pwordexp, ifs, ifs_white);
-
-	if (error)
-	  goto do_error;
-
-	if (!word_length)
-	  {
-	    error = w_addword (pwordexp, NULL);
-
-	    if (error)
-	      return error;
-	  }
-
-	break;
-
-      case '\'':
-	++words_offset;
-	error = parse_squote (&word, &word_length, &max_length, words,
-			      &words_offset);
-
-	if (error)
-	  goto do_error;
-
-	if (!word_length)
-	  {
-	    error = w_addword (pwordexp, NULL);
-
-	    if (error)
-	      return error;
-	  }
-
-	break;
-
-      case '~':
-	error = parse_tilde (&word, &word_length, &max_length, words,
-			     &words_offset, pwordexp->we_wordc);
-
-	if (error)
-	  goto do_error;
-
-	break;
-
-      case '*':
-      case '[':
-      case '?':
-	error = parse_glob (&word, &word_length, &max_length, words,
-			    &words_offset, flags, pwordexp, ifs, ifs_white);
-
-	if (error)
-	  goto do_error;
-
-	break;
-
-      default:
-	/* Is it a word separator? */
-	if (strchr (" \t", words[words_offset]) == NULL)
-	  {
-	    char ch = words[words_offset];
-
-	    /* Not a word separator -- but is it a valid word char? */
-	    if (strchr ("\n|&;<>(){}", ch))
-	      {
-		/* Fail */
-		error = WRDE_BADCHAR;
-		goto do_error;
-	      }
-
-	    /* "Ordinary" character -- add it to word */
-	    word = w_addchar (word, &word_length, &max_length,
-			      ch);
-	    if (word == NULL)
-	      {
-		error = WRDE_NOSPACE;
-		goto do_error;
-	      }
-
-	    break;
-	  }
-
-	/* If a word has been delimited, add it to the list. */
-	if (word != NULL)
-	  {
-	    error = w_addword (pwordexp, word);
-	    if (error)
-	      goto do_error;
-	  }
-
-	word = w_newword (&word_length, &max_length);
-      }
-
-  /* End of string */
-
-  /* There was a word separator at the end */
-  if (word == NULL) /* i.e. w_newword */
-    return 0;
-
-  /* There was no field separator at the end */
-  return w_addword (pwordexp, word);
-
-do_error:
-  /* Error:
-   *	free memory used (unless error is WRDE_NOSPACE), and
-   *	set pwordexp members back to what they were.
-   */
-
-  if (word != NULL)
-    free (word);
-
-  if (error == WRDE_NOSPACE)
-    return WRDE_NOSPACE;
-
-  if ((flags & WRDE_APPEND) == 0)
-    wordfree (pwordexp);
-
-  *pwordexp = old_word;
-  return error;
-}