--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lib/argp-parse.c	Tue Dec 22 05:31:23 2009 +0000
@@ -0,0 +1,952 @@
+/* Hierarchial argument parsing, layered over getopt
+   Copyright (C) 1995-2000, 2002, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Written by Miles Bader <miles@gnu.ai.mit.edu>.
+
+   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 of the License, 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, see <http://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <alloca.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <limits.h>
+#include <getopt.h>
+#include <getopt_int.h>
+
+#ifdef _LIBC
+# include <libintl.h>
+# undef dgettext
+# define dgettext(domain, msgid) \
+   INTUSE(__dcgettext) (domain, msgid, LC_MESSAGES)
+#else
+# include "gettext.h"
+#endif
+#define N_(msgid) msgid
+
+#include "argp.h"
+#include "argp-namefrob.h"
+
+#define alignof(type) offsetof (struct { char c; type x; }, x)
+#define alignto(n, d) ((((n) + (d) - 1) / (d)) * (d))
+
+/* Getopt return values.  */
+#define KEY_END (-1)		/* The end of the options.  */
+#define KEY_ARG 1		/* A non-option argument.  */
+#define KEY_ERR '?'		/* An error parsing the options.  */
+
+/* The meta-argument used to prevent any further arguments being interpreted
+   as options.  */
+#define QUOTE "--"
+
+/* The number of bits we steal in a long-option value for our own use.  */
+#define GROUP_BITS CHAR_BIT
+
+/* The number of bits available for the user value.  */
+#define USER_BITS ((sizeof ((struct option *)0)->val * CHAR_BIT) - GROUP_BITS)
+#define USER_MASK ((1 << USER_BITS) - 1)
+
+/* EZ alias for ARGP_ERR_UNKNOWN.  */
+#define EBADKEY ARGP_ERR_UNKNOWN
+
+/* Default options.  */
+
+/* When argp is given the --HANG switch, _ARGP_HANG is set and argp will sleep
+   for one second intervals, decrementing _ARGP_HANG until it's zero.  Thus
+   you can force the program to continue by attaching a debugger and setting
+   it to 0 yourself.  */
+static volatile int _argp_hang;
+
+#define OPT_PROGNAME	-2
+#define OPT_USAGE	-3
+#define OPT_HANG	-4
+
+static const struct argp_option argp_default_options[] =
+{
+  {"help",	  '?',    	0, 0,  N_("give this help list"), -1},
+  {"usage",	  OPT_USAGE,	0, 0,  N_("give a short usage message"), 0},
+  {"program-name",OPT_PROGNAME,N_("NAME"), OPTION_HIDDEN, N_("set the program name"), 0},
+  {"HANG",	  OPT_HANG,    N_("SECS"), OPTION_ARG_OPTIONAL | OPTION_HIDDEN,
+     N_("hang for SECS seconds (default 3600)"), 0},
+  {NULL, 0, 0, 0, NULL, 0}
+};
+
+static error_t
+argp_default_parser (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case '?':
+      __argp_state_help (state, state->out_stream, ARGP_HELP_STD_HELP);
+      break;
+    case OPT_USAGE:
+      __argp_state_help (state, state->out_stream,
+			 ARGP_HELP_USAGE | ARGP_HELP_EXIT_OK);
+      break;
+
+    case OPT_PROGNAME:		/* Set the program name.  */
+#if defined _LIBC || HAVE_DECL_PROGRAM_INVOCATION_NAME
+      program_invocation_name = arg;
+#endif
+      /* [Note that some systems only have PROGRAM_INVOCATION_SHORT_NAME (aka
+	 __PROGNAME), in which case, PROGRAM_INVOCATION_NAME is just defined
+	 to be that, so we have to be a bit careful here.]  */
+
+      /* Update what we use for messages.  */
+      state->name = __argp_base_name (arg);
+
+#if defined _LIBC || HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME
+      program_invocation_short_name = state->name;
+#endif
+
+      if ((state->flags & (ARGP_PARSE_ARGV0 | ARGP_NO_ERRS))
+	  == ARGP_PARSE_ARGV0)
+	/* Update what getopt uses too.  */
+	state->argv[0] = arg;
+
+      break;
+
+    case OPT_HANG:
+      _argp_hang = atoi (arg ? arg : "3600");
+      while (_argp_hang-- > 0)
+	__sleep (1);
+      break;
+
+    default:
+      return EBADKEY;
+    }
+  return 0;
+}
+
+static const struct argp argp_default_argp =
+  {argp_default_options, &argp_default_parser, NULL, NULL, NULL, NULL, "libc"};
+
+
+static const struct argp_option argp_version_options[] =
+{
+  {"version",	  'V',    	0, 0,  N_("print program version"), -1},
+  {NULL, 0, 0, 0, NULL, 0}
+};
+
+static error_t
+argp_version_parser (int key, char *arg, struct argp_state *state)
+{
+  switch (key)
+    {
+    case 'V':
+      if (argp_program_version_hook)
+	(*argp_program_version_hook) (state->out_stream, state);
+      else if (argp_program_version)
+	fprintf (state->out_stream, "%s\n", argp_program_version);
+      else
+	__argp_error (state, dgettext (state->root_argp->argp_domain,
+				       "(PROGRAM ERROR) No version known!?"));
+      if (! (state->flags & ARGP_NO_EXIT))
+	exit (0);
+      break;
+    default:
+      return EBADKEY;
+    }
+  return 0;
+}
+
+static const struct argp argp_version_argp =
+  {argp_version_options, &argp_version_parser, NULL, NULL, NULL, NULL, "libc"};
+
+/* Returns the offset into the getopt long options array LONG_OPTIONS of a
+   long option with called NAME, or -1 if none is found.  Passing NULL as
+   NAME will return the number of options.  */
+static int
+find_long_option (struct option *long_options, const char *name)
+{
+  struct option *l = long_options;
+  while (l->name != NULL)
+    if (name != NULL && strcmp (l->name, name) == 0)
+      return l - long_options;
+    else
+      l++;
+  if (name == NULL)
+    return l - long_options;
+  else
+    return -1;
+}
+
+
+/* The state of a `group' during parsing.  Each group corresponds to a
+   particular argp structure from the tree of such descending from the top
+   level argp passed to argp_parse.  */
+struct group
+{
+  /* This group's parsing function.  */
+  argp_parser_t parser;
+
+  /* Which argp this group is from.  */
+  const struct argp *argp;
+
+  /* Points to the point in SHORT_OPTS corresponding to the end of the short
+     options for this group.  We use it to determine from which group a
+     particular short options is from.  */
+  char *short_end;
+
+  /* The number of non-option args sucessfully handled by this parser.  */
+  unsigned args_processed;
+
+  /* This group's parser's parent's group.  */
+  struct group *parent;
+  unsigned parent_index;	/* And the our position in the parent.   */
+
+  /* These fields are swapped into and out of the state structure when
+     calling this group's parser.  */
+  void *input, **child_inputs;
+  void *hook;
+};
+
+/* Call GROUP's parser with KEY and ARG, swapping any group-specific info
+   from STATE before calling, and back into state afterwards.  If GROUP has
+   no parser, EBADKEY is returned.  */
+static error_t
+group_parse (struct group *group, struct argp_state *state, int key, char *arg)
+{
+  if (group->parser)
+    {
+      error_t err;
+      state->hook = group->hook;
+      state->input = group->input;
+      state->child_inputs = group->child_inputs;
+      state->arg_num = group->args_processed;
+      err = (*group->parser)(key, arg, state);
+      group->hook = state->hook;
+      return err;
+    }
+  else
+    return EBADKEY;
+}
+
+struct parser
+{
+  const struct argp *argp;
+
+  /* SHORT_OPTS is the getopt short options string for the union of all the
+     groups of options.  */
+  char *short_opts;
+  /* LONG_OPTS is the array of getop long option structures for the union of
+     all the groups of options.  */
+  struct option *long_opts;
+  /* OPT_DATA is the getopt data used for the re-entrant getopt.  */
+  struct _getopt_data opt_data;
+
+  /* States of the various parsing groups.  */
+  struct group *groups;
+  /* The end of the GROUPS array.  */
+  struct group *egroup;
+  /* An vector containing storage for the CHILD_INPUTS field in all groups.  */
+  void **child_inputs;
+
+  /* True if we think using getopt is still useful; if false, then
+     remaining arguments are just passed verbatim with ARGP_KEY_ARG.  This is
+     cleared whenever getopt returns KEY_END, but may be set again if the user
+     moves the next argument pointer backwards.  */
+  int try_getopt;
+
+  /* State block supplied to parsing routines.  */
+  struct argp_state state;
+
+  /* Memory used by this parser.  */
+  void *storage;
+};
+
+/* The next usable entries in the various parser tables being filled in by
+   convert_options.  */
+struct parser_convert_state
+{
+  struct parser *parser;
+  char *short_end;
+  struct option *long_end;
+  void **child_inputs_end;
+};
+
+/* Converts all options in ARGP (which is put in GROUP) and ancestors
+   into getopt options stored in SHORT_OPTS and LONG_OPTS; SHORT_END and
+   CVT->LONG_END are the points at which new options are added.  Returns the
+   next unused group entry.  CVT holds state used during the conversion.  */
+static struct group *
+convert_options (const struct argp *argp,
+		 struct group *parent, unsigned parent_index,
+		 struct group *group, struct parser_convert_state *cvt)
+{
+  /* REAL is the most recent non-alias value of OPT.  */
+  const struct argp_option *real = argp->options;
+  const struct argp_child *children = argp->children;
+
+  if (real || argp->parser)
+    {
+      const struct argp_option *opt;
+
+      if (real)
+	for (opt = real; !__option_is_end (opt); opt++)
+	  {
+	    if (! (opt->flags & OPTION_ALIAS))
+	      /* OPT isn't an alias, so we can use values from it.  */
+	      real = opt;
+
+	    if (! (real->flags & OPTION_DOC))
+	      /* A real option (not just documentation).  */
+	      {
+		if (__option_is_short (opt))
+		  /* OPT can be used as a short option.  */
+		  {
+		    *cvt->short_end++ = opt->key;
+		    if (real->arg)
+		      {
+			*cvt->short_end++ = ':';
+			if (real->flags & OPTION_ARG_OPTIONAL)
+			  *cvt->short_end++ = ':';
+		      }
+		    *cvt->short_end = '\0'; /* keep 0 terminated */
+		  }
+
+		if (opt->name
+		    && find_long_option (cvt->parser->long_opts, opt->name) < 0)
+		  /* OPT can be used as a long option.  */
+		  {
+		    cvt->long_end->name = opt->name;
+		    cvt->long_end->has_arg =
+		      (real->arg
+		       ? (real->flags & OPTION_ARG_OPTIONAL
+			  ? optional_argument
+			  : required_argument)
+		       : no_argument);
+		    cvt->long_end->flag = 0;
+		    /* we add a disambiguating code to all the user's
+		       values (which is removed before we actually call
+		       the function to parse the value); this means that
+		       the user loses use of the high 8 bits in all his
+		       values (the sign of the lower bits is preserved
+		       however)...  */
+		    cvt->long_end->val =
+		      ((opt->key | real->key) & USER_MASK)
+		      + (((group - cvt->parser->groups) + 1) << USER_BITS);
+
+		    /* Keep the LONG_OPTS list terminated.  */
+		    (++cvt->long_end)->name = NULL;
+		  }
+	      }
+	    }
+
+      group->parser = argp->parser;
+      group->argp = argp;
+      group->short_end = cvt->short_end;
+      group->args_processed = 0;
+      group->parent = parent;
+      group->parent_index = parent_index;
+      group->input = 0;
+      group->hook = 0;
+      group->child_inputs = 0;
+
+      if (children)
+	/* Assign GROUP's CHILD_INPUTS field some space from
+           CVT->child_inputs_end.*/
+	{
+	  unsigned num_children = 0;
+	  while (children[num_children].argp)
+	    num_children++;
+	  group->child_inputs = cvt->child_inputs_end;
+	  cvt->child_inputs_end += num_children;
+	}
+
+      parent = group++;
+    }
+  else
+    parent = 0;
+
+  if (children)
+    {
+      unsigned index = 0;
+      while (children->argp)
+	group =
+	  convert_options (children++->argp, parent, index++, group, cvt);
+    }
+
+  return group;
+}
+
+/* Find the merged set of getopt options, with keys appropiately prefixed. */
+static void
+parser_convert (struct parser *parser, const struct argp *argp, int flags)
+{
+  struct parser_convert_state cvt;
+
+  cvt.parser = parser;
+  cvt.short_end = parser->short_opts;
+  cvt.long_end = parser->long_opts;
+  cvt.child_inputs_end = parser->child_inputs;
+
+  if (flags & ARGP_IN_ORDER)
+    *cvt.short_end++ = '-';
+  else if (flags & ARGP_NO_ARGS)
+    *cvt.short_end++ = '+';
+  *cvt.short_end = '\0';
+
+  cvt.long_end->name = NULL;
+
+  parser->argp = argp;
+
+  if (argp)
+    parser->egroup = convert_options (argp, 0, 0, parser->groups, &cvt);
+  else
+    parser->egroup = parser->groups; /* No parsers at all! */
+}
+
+/* Lengths of various parser fields which we will allocated.  */
+struct parser_sizes
+{
+  size_t short_len;		/* Getopt short options string.  */
+  size_t long_len;		/* Getopt long options vector.  */
+  size_t num_groups;		/* Group structures we allocate.  */
+  size_t num_child_inputs;	/* Child input slots.  */
+};
+
+/* For ARGP, increments the NUM_GROUPS field in SZS by the total number of
+ argp structures descended from it, and the SHORT_LEN & LONG_LEN fields by
+ the maximum lengths of the resulting merged getopt short options string and
+ long-options array, respectively.  */
+static void
+calc_sizes (const struct argp *argp,  struct parser_sizes *szs)
+{
+  const struct argp_child *child = argp->children;
+  const struct argp_option *opt = argp->options;
+
+  if (opt || argp->parser)
+    {
+      szs->num_groups++;
+      if (opt)
+	{
+	  int num_opts = 0;
+	  while (!__option_is_end (opt++))
+	    num_opts++;
+	  szs->short_len += num_opts * 3; /* opt + up to 2 `:'s */
+	  szs->long_len += num_opts;
+	}
+    }
+
+  if (child)
+    while (child->argp)
+      {
+	calc_sizes ((child++)->argp, szs);
+	szs->num_child_inputs++;
+      }
+}
+
+/* Initializes PARSER to parse ARGP in a manner described by FLAGS.  */
+static error_t
+parser_init (struct parser *parser, const struct argp *argp,
+	     int argc, char **argv, int flags, void *input)
+{
+  error_t err = 0;
+  struct group *group;
+  struct parser_sizes szs;
+  struct _getopt_data opt_data = _GETOPT_DATA_INITIALIZER;
+  char *storage;
+  size_t glen, gsum;
+  size_t clen, csum;
+  size_t llen, lsum;
+  size_t slen, ssum;
+
+  szs.short_len = (flags & ARGP_NO_ARGS) ? 0 : 1;
+  szs.long_len = 0;
+  szs.num_groups = 0;
+  szs.num_child_inputs = 0;
+
+  if (argp)
+    calc_sizes (argp, &szs);
+
+  /* Lengths of the various bits of storage used by PARSER.  */
+  glen = (szs.num_groups + 1) * sizeof (struct group);
+  clen = szs.num_child_inputs * sizeof (void *);
+  llen = (szs.long_len + 1) * sizeof (struct option);
+  slen = szs.short_len + 1;
+
+  /* Sums of previous lengths, properly aligned.  There's no need to
+     align gsum, since struct group is aligned at least as strictly as
+     void * (since it contains a void * member).  And there's no need
+     to align lsum, since struct option is aligned at least as
+     strictly as char.  */
+  gsum = glen;
+  csum = alignto (gsum + clen, alignof (struct option));
+  lsum = csum + llen;
+  ssum = lsum + slen;
+
+  parser->storage = malloc (ssum);
+  if (! parser->storage)
+    return ENOMEM;
+
+  storage = parser->storage;
+  parser->groups = parser->storage;
+  parser->child_inputs = (void **) (storage + gsum);
+  parser->long_opts = (struct option *) (storage + csum);
+  parser->short_opts = storage + lsum;
+  parser->opt_data = opt_data;
+
+  memset (parser->child_inputs, 0, clen);
+  parser_convert (parser, argp, flags);
+
+  memset (&parser->state, 0, sizeof (struct argp_state));
+  parser->state.root_argp = parser->argp;
+  parser->state.argc = argc;
+  parser->state.argv = argv;
+  parser->state.flags = flags;
+  parser->state.err_stream = stderr;
+  parser->state.out_stream = stdout;
+  parser->state.next = 0;	/* Tell getopt to initialize.  */
+  parser->state.pstate = parser;
+
+  parser->try_getopt = 1;
+
+  /* Call each parser for the first time, giving it a chance to propagate
+     values to child parsers.  */
+  if (parser->groups < parser->egroup)
+    parser->groups->input = input;
+  for (group = parser->groups;
+       group < parser->egroup && (!err || err == EBADKEY);
+       group++)
+    {
+      if (group->parent)
+	/* If a child parser, get the initial input value from the parent. */
+	group->input = group->parent->child_inputs[group->parent_index];
+
+      if (!group->parser
+	  && group->argp->children && group->argp->children->argp)
+	/* For the special case where no parsing function is supplied for an
+	   argp, propagate its input to its first child, if any (this just
+	   makes very simple wrapper argps more convenient).  */
+	group->child_inputs[0] = group->input;
+
+      err = group_parse (group, &parser->state, ARGP_KEY_INIT, 0);
+    }
+  if (err == EBADKEY)
+    err = 0;			/* Some parser didn't understand.  */
+
+  if (err)
+    return err;
+
+  if (parser->state.flags & ARGP_NO_ERRS)
+    {
+      parser->opt_data.opterr = 0;
+      if (parser->state.flags & ARGP_PARSE_ARGV0)
+	/* getopt always skips ARGV[0], so we have to fake it out.  As long
+	   as OPTERR is 0, then it shouldn't actually try to access it.  */
+	parser->state.argv--, parser->state.argc++;
+    }
+  else
+    parser->opt_data.opterr = 1;	/* Print error messages.  */
+
+  if (parser->state.argv == argv && argv[0])
+    /* There's an argv[0]; use it for messages.  */
+    parser->state.name = __argp_base_name (argv[0]);
+  else
+    parser->state.name = __argp_short_program_name ();
+
+  return 0;
+}
+
+/* Free any storage consumed by PARSER (but not PARSER itself).  */
+static error_t
+parser_finalize (struct parser *parser,
+		 error_t err, int arg_ebadkey, int *end_index)
+{
+  struct group *group;
+
+  if (err == EBADKEY && arg_ebadkey)
+    /* Suppress errors generated by unparsed arguments.  */
+    err = 0;
+
+  if (! err)
+    {
+      if (parser->state.next == parser->state.argc)
+	/* We successfully parsed all arguments!  Call all the parsers again,
+	   just a few more times... */
+	{
+	  for (group = parser->groups;
+	       group < parser->egroup && (!err || err==EBADKEY);
+	       group++)
+	    if (group->args_processed == 0)
+	      err = group_parse (group, &parser->state, ARGP_KEY_NO_ARGS, 0);
+	  for (group = parser->egroup - 1;
+	       group >= parser->groups && (!err || err==EBADKEY);
+	       group--)
+	    err = group_parse (group, &parser->state, ARGP_KEY_END, 0);
+
+	  if (err == EBADKEY)
+	    err = 0;		/* Some parser didn't understand.  */
+
+	  /* Tell the user that all arguments are parsed.  */
+	  if (end_index)
+	    *end_index = parser->state.next;
+	}
+      else if (end_index)
+	/* Return any remaining arguments to the user.  */
+	*end_index = parser->state.next;
+      else
+	/* No way to return the remaining arguments, they must be bogus. */
+	{
+	  if (!(parser->state.flags & ARGP_NO_ERRS)
+	      && parser->state.err_stream)
+	    fprintf (parser->state.err_stream,
+		     dgettext (parser->argp->argp_domain,
+			       "%s: Too many arguments\n"),
+		     parser->state.name);
+	  err = EBADKEY;
+	}
+    }
+
+  /* Okay, we're all done, with either an error or success; call the parsers
+     to indicate which one.  */
+
+  if (err)
+    {
+      /* Maybe print an error message.  */
+      if (err == EBADKEY)
+	/* An appropriate message describing what the error was should have
+	   been printed earlier.  */
+	__argp_state_help (&parser->state, parser->state.err_stream,
+			   ARGP_HELP_STD_ERR);
+
+      /* Since we didn't exit, give each parser an error indication.  */
+      for (group = parser->groups; group < parser->egroup; group++)
+	group_parse (group, &parser->state, ARGP_KEY_ERROR, 0);
+    }
+  else
+    /* Notify parsers of success, and propagate back values from parsers.  */
+    {
+      /* We pass over the groups in reverse order so that child groups are
+	 given a chance to do there processing before passing back a value to
+	 the parent.  */
+      for (group = parser->egroup - 1
+	   ; group >= parser->groups && (!err || err == EBADKEY)
+	   ; group--)
+	err = group_parse (group, &parser->state, ARGP_KEY_SUCCESS, 0);
+      if (err == EBADKEY)
+	err = 0;		/* Some parser didn't understand.  */
+    }
+
+  /* Call parsers once more, to do any final cleanup.  Errors are ignored.  */
+  for (group = parser->egroup - 1; group >= parser->groups; group--)
+    group_parse (group, &parser->state, ARGP_KEY_FINI, 0);
+
+  if (err == EBADKEY)
+    err = EINVAL;
+
+  free (parser->storage);
+
+  return err;
+}
+
+/* Call the user parsers to parse the non-option argument VAL, at the current
+   position, returning any error.  The state NEXT pointer is assumed to have
+   been adjusted (by getopt) to point after this argument; this function will
+   adjust it correctly to reflect however many args actually end up being
+   consumed.  */
+static error_t
+parser_parse_arg (struct parser *parser, char *val)
+{
+  /* Save the starting value of NEXT, first adjusting it so that the arg
+     we're parsing is again the front of the arg vector.  */
+  int index = --parser->state.next;
+  error_t err = EBADKEY;
+  struct group *group;
+  int key = 0;			/* Which of ARGP_KEY_ARG[S] we used.  */
+
+  /* Try to parse the argument in each parser.  */
+  for (group = parser->groups
+       ; group < parser->egroup && err == EBADKEY
+       ; group++)
+    {
+      parser->state.next++;	/* For ARGP_KEY_ARG, consume the arg.  */
+      key = ARGP_KEY_ARG;
+      err = group_parse (group, &parser->state, key, val);
+
+      if (err == EBADKEY)
+	/* This parser doesn't like ARGP_KEY_ARG; try ARGP_KEY_ARGS instead. */
+	{
+	  parser->state.next--;	/* For ARGP_KEY_ARGS, put back the arg.  */
+	  key = ARGP_KEY_ARGS;
+	  err = group_parse (group, &parser->state, key, 0);
+	}
+    }
+
+  if (! err)
+    {
+      if (key == ARGP_KEY_ARGS)
+	/* The default for ARGP_KEY_ARGS is to assume that if NEXT isn't
+	   changed by the user, *all* arguments should be considered
+	   consumed.  */
+	parser->state.next = parser->state.argc;
+
+      if (parser->state.next > index)
+	/* Remember that we successfully processed a non-option
+	   argument -- but only if the user hasn't gotten tricky and set
+	   the clock back.  */
+	(--group)->args_processed += (parser->state.next - index);
+      else
+	/* The user wants to reparse some args, give getopt another try.  */
+	parser->try_getopt = 1;
+    }
+
+  return err;
+}
+
+/* Call the user parsers to parse the option OPT, with argument VAL, at the
+   current position, returning any error.  */
+static error_t
+parser_parse_opt (struct parser *parser, int opt, char *val)
+{
+  /* The group key encoded in the high bits; 0 for short opts or
+     group_number + 1 for long opts.  */
+  int group_key = opt >> USER_BITS;
+  error_t err = EBADKEY;
+
+  if (group_key == 0)
+    /* A short option.  By comparing OPT's position in SHORT_OPTS to the
+       various starting positions in each group's SHORT_END field, we can
+       determine which group OPT came from.  */
+    {
+      struct group *group;
+      char *short_index = strchr (parser->short_opts, opt);
+
+      if (short_index)
+	for (group = parser->groups; group < parser->egroup; group++)
+	  if (group->short_end > short_index)
+	    {
+	      err = group_parse (group, &parser->state, opt,
+				 parser->opt_data.optarg);
+	      break;
+	    }
+    }
+  else
+    /* A long option.  We use shifts instead of masking for extracting
+       the user value in order to preserve the sign.  */
+    err =
+      group_parse (&parser->groups[group_key - 1], &parser->state,
+		   (opt << GROUP_BITS) >> GROUP_BITS,
+		   parser->opt_data.optarg);
+
+  if (err == EBADKEY)
+    /* At least currently, an option not recognized is an error in the
+       parser, because we pre-compute which parser is supposed to deal
+       with each option.  */
+    {
+      static const char bad_key_err[] =
+	N_("(PROGRAM ERROR) Option should have been recognized!?");
+      if (group_key == 0)
+	__argp_error (&parser->state, "-%c: %s", opt,
+		      dgettext (parser->argp->argp_domain, bad_key_err));
+      else
+	{
+	  struct option *long_opt = parser->long_opts;
+	  while (long_opt->val != opt && long_opt->name)
+	    long_opt++;
+	  __argp_error (&parser->state, "--%s: %s",
+			long_opt->name ? long_opt->name : "???",
+			dgettext (parser->argp->argp_domain, bad_key_err));
+	}
+    }
+
+  return err;
+}
+
+/* Parse the next argument in PARSER (as indicated by PARSER->state.next).
+   Any error from the parsers is returned, and *ARGP_EBADKEY indicates
+   whether a value of EBADKEY is due to an unrecognized argument (which is
+   generally not fatal).  */
+static error_t
+parser_parse_next (struct parser *parser, int *arg_ebadkey)
+{
+  int opt;
+  error_t err = 0;
+
+  if (parser->state.quoted && parser->state.next < parser->state.quoted)
+    /* The next argument pointer has been moved to before the quoted
+       region, so pretend we never saw the quoting `--', and give getopt
+       another chance.  If the user hasn't removed it, getopt will just
+       process it again.  */
+    parser->state.quoted = 0;
+
+  if (parser->try_getopt && !parser->state.quoted)
+    /* Give getopt a chance to parse this.  */
+    {
+      /* Put it back in OPTIND for getopt.  */
+      parser->opt_data.optind = parser->state.next;
+      /* Distinguish KEY_ERR from a real option.  */
+      parser->opt_data.optopt = KEY_END;
+      if (parser->state.flags & ARGP_LONG_ONLY)
+	opt = _getopt_long_only_r (parser->state.argc, parser->state.argv,
+				   parser->short_opts, parser->long_opts, 0,
+				   &parser->opt_data);
+      else
+	opt = _getopt_long_r (parser->state.argc, parser->state.argv,
+			      parser->short_opts, parser->long_opts, 0,
+			      &parser->opt_data);
+      /* And see what getopt did.  */
+      parser->state.next = parser->opt_data.optind;
+
+      if (opt == KEY_END)
+	/* Getopt says there are no more options, so stop using
+	   getopt; we'll continue if necessary on our own.  */
+	{
+	  parser->try_getopt = 0;
+	  if (parser->state.next > 1
+	      && strcmp (parser->state.argv[parser->state.next - 1], QUOTE)
+	           == 0)
+	    /* Not only is this the end of the options, but it's a
+	       `quoted' region, which may have args that *look* like
+	       options, so we definitely shouldn't try to use getopt past
+	       here, whatever happens.  */
+	    parser->state.quoted = parser->state.next;
+	}
+      else if (opt == KEY_ERR && parser->opt_data.optopt != KEY_END)
+	/* KEY_ERR can have the same value as a valid user short
+	   option, but in the case of a real error, getopt sets OPTOPT
+	   to the offending character, which can never be KEY_END.  */
+	{
+	  *arg_ebadkey = 0;
+	  return EBADKEY;
+	}
+    }
+  else
+    opt = KEY_END;
+
+  if (opt == KEY_END)
+    {
+      /* We're past what getopt considers the options.  */
+      if (parser->state.next >= parser->state.argc
+	  || (parser->state.flags & ARGP_NO_ARGS))
+	/* Indicate that we're done.  */
+	{
+	  *arg_ebadkey = 1;
+	  return EBADKEY;
+	}
+      else
+	/* A non-option arg; simulate what getopt might have done.  */
+	{
+	  opt = KEY_ARG;
+	  parser->opt_data.optarg = parser->state.argv[parser->state.next++];
+	}
+    }
+
+  if (opt == KEY_ARG)
+    /* A non-option argument; try each parser in turn.  */
+    err = parser_parse_arg (parser, parser->opt_data.optarg);
+  else
+    err = parser_parse_opt (parser, opt, parser->opt_data.optarg);
+
+  if (err == EBADKEY)
+    *arg_ebadkey = (opt == KEY_END || opt == KEY_ARG);
+
+  return err;
+}
+
+/* Parse the options strings in ARGC & ARGV according to the argp in ARGP.
+   FLAGS is one of the ARGP_ flags above.  If END_INDEX is non-NULL, the
+   index in ARGV of the first unparsed option is returned in it.  If an
+   unknown option is present, EINVAL is returned; if some parser routine
+   returned a non-zero value, it is returned; otherwise 0 is returned.  */
+error_t
+__argp_parse (const struct argp *argp, int argc, char **argv, unsigned flags,
+	      int *end_index, void *input)
+{
+  error_t err;
+  struct parser parser;
+
+  /* If true, then err == EBADKEY is a result of a non-option argument failing
+     to be parsed (which in some cases isn't actually an error).  */
+  int arg_ebadkey = 0;
+
+#ifndef _LIBC
+  if (!(flags & ARGP_PARSE_ARGV0))
+    {
+#ifdef HAVE_DECL_PROGRAM_INVOCATION_NAME
+      if (!program_invocation_name)
+	program_invocation_name = argv[0];
+#endif
+#ifdef HAVE_DECL_PROGRAM_INVOCATION_SHORT_NAME
+      if (!program_invocation_short_name)
+	program_invocation_short_name = __argp_base_name (argv[0]);
+#endif
+    }
+#endif
+
+  if (! (flags & ARGP_NO_HELP))
+    /* Add our own options.  */
+    {
+      struct argp_child *child = alloca (4 * sizeof (struct argp_child));
+      struct argp *top_argp = alloca (sizeof (struct argp));
+
+      /* TOP_ARGP has no options, it just serves to group the user & default
+	 argps.  */
+      memset (top_argp, 0, sizeof (*top_argp));
+      top_argp->children = child;
+
+      memset (child, 0, 4 * sizeof (struct argp_child));
+
+      if (argp)
+	(child++)->argp = argp;
+      (child++)->argp = &argp_default_argp;
+      if (argp_program_version || argp_program_version_hook)
+	(child++)->argp = &argp_version_argp;
+      child->argp = 0;
+
+      argp = top_argp;
+    }
+
+  /* Construct a parser for these arguments.  */
+  err = parser_init (&parser, argp, argc, argv, flags, input);
+
+  if (! err)
+    /* Parse! */
+    {
+      while (! err)
+	err = parser_parse_next (&parser, &arg_ebadkey);
+      err = parser_finalize (&parser, err, arg_ebadkey, end_index);
+    }
+
+  return err;
+}
+#ifdef weak_alias
+weak_alias (__argp_parse, argp_parse)
+#endif
+
+/* Return the input field for ARGP in the parser corresponding to STATE; used
+   by the help routines.  */
+void *
+__argp_input (const struct argp *argp, const struct argp_state *state)
+{
+  if (state)
+    {
+      struct group *group;
+      struct parser *parser = state->pstate;
+
+      for (group = parser->groups; group < parser->egroup; group++)
+	if (group->argp == argp)
+	  return group->input;
+    }
+
+  return 0;
+}
+#ifdef weak_alias
+weak_alias (__argp_input, _argp_input)
+#endif