/* CLI utilities.

   Copyright (c) 2011 Free Software Foundation, Inc.

   This file is part of GDB.

   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/>.  */

#include "defs.h"
#include "cli/cli-utils.h"
#include "gdb_string.h"
#include "value.h"
#include "gdb_assert.h"

#include <ctype.h>

/* *PP is a string denoting a number.  Get the number of the.  Advance
   *PP after the string and any trailing whitespace.

   Currently the string can either be a number, or "$" followed by the
   name of a convenience variable, or ("$" or "$$") followed by digits.

   TRAILER is a character which can be found after the number; most
   commonly this is `-'.  If you don't want a trailer, use \0.  */

static int
get_number_trailer (char **pp, int trailer)
{
  int retval = 0;	/* default */
  char *p = *pp;

  if (*p == '$')
    {
      struct value *val = value_from_history_ref (p, &p);

      if (val)	/* Value history reference */
	{
	  if (TYPE_CODE (value_type (val)) == TYPE_CODE_INT)
	    retval = value_as_long (val);
	  else
	    {
	      printf_filtered (_("History value must have integer type."));
	      retval = 0;
	    }
	}
      else	/* Convenience variable */
	{
	  /* Internal variable.  Make a copy of the name, so we can
	     null-terminate it to pass to lookup_internalvar().  */
	  char *varname;
	  char *start = ++p;
	  LONGEST val;

	  while (isalnum (*p) || *p == '_')
	    p++;
	  varname = (char *) alloca (p - start + 1);
	  strncpy (varname, start, p - start);
	  varname[p - start] = '\0';
	  if (get_internalvar_integer (lookup_internalvar (varname), &val))
	    retval = (int) val;
	  else
	    {
	      printf_filtered (_("Convenience variable must "
				 "have integer value.\n"));
	      retval = 0;
	    }
	}
    }
  else
    {
      if (*p == '-')
	++p;
      while (*p >= '0' && *p <= '9')
	++p;
      if (p == *pp)
	/* There is no number here.  (e.g. "cond a == b").  */
	{
	  /* Skip non-numeric token.  */
	  while (*p && !isspace((int) *p))
	    ++p;
	  /* Return zero, which caller must interpret as error.  */
	  retval = 0;
	}
      else
	retval = atoi (*pp);
    }
  if (!(isspace (*p) || *p == '\0' || *p == trailer))
    {
      /* Trailing junk: return 0 and let caller print error msg.  */
      while (!(isspace (*p) || *p == '\0' || *p == trailer))
	++p;
      retval = 0;
    }
  p = skip_spaces (p);
  *pp = p;
  return retval;
}

/* See documentation in cli-utils.h.  */

int
get_number (char **pp)
{
  return get_number_trailer (pp, '\0');
}

/* See documentation in cli-utils.h.  */

int
get_number_or_range (char **pp)
{
  static int last_retval, end_value;
  static char *end_ptr;
  static int in_range = 0;

  if (**pp != '-')
    {
      /* Default case: pp is pointing either to a solo number, 
	 or to the first number of a range.  */
      last_retval = get_number_trailer (pp, '-');
      if (**pp == '-')
	{
	  char **temp;

	  /* This is the start of a range (<number1> - <number2>).
	     Skip the '-', parse and remember the second number,
	     and also remember the end of the final token.  */

	  temp = &end_ptr; 
	  end_ptr = *pp + 1; 
	  while (isspace ((int) *end_ptr))
	    end_ptr++;	/* skip white space */
	  end_value = get_number (temp);
	  if (end_value < last_retval) 
	    {
	      error (_("inverted range"));
	    }
	  else if (end_value == last_retval)
	    {
	      /* Degenerate range (number1 == number2).  Advance the
		 token pointer so that the range will be treated as a
		 single number.  */ 
	      *pp = end_ptr;
	    }
	  else
	    in_range = 1;
	}
    }
  else if (! in_range)
    error (_("negative value"));
  else
    {
      /* pp points to the '-' that betokens a range.  All
	 number-parsing has already been done.  Return the next
	 integer value (one greater than the saved previous value).
	 Do not advance the token pointer 'pp' until the end of range
	 is reached.  */

      if (++last_retval == end_value)
	{
	  /* End of range reached; advance token pointer.  */
	  *pp = end_ptr;
	  in_range = 0;
	}
    }
  return last_retval;
}

/* Accept a number and a string-form list of numbers such as is 
   accepted by get_number_or_range.  Return TRUE if the number is
   in the list.

   By definition, an empty list includes all numbers.  This is to 
   be interpreted as typing a command such as "delete break" with 
   no arguments.  */

int
number_is_in_list (char *list, int number)
{
  if (list == NULL || *list == '\0')
    return 1;

  while (*list != '\0')
    {
      int gotnum = get_number_or_range (&list);

      if (gotnum == 0)
	error (_("Args must be numbers or '$' variables."));
      if (gotnum == number)
	return 1;
    }
  return 0;
}

/* See documentation in cli-utils.h.  */

char *
skip_spaces (char *chp)
{
  if (chp == NULL)
    return NULL;
  while (*chp && isspace (*chp))
    chp++;
  return chp;
}

/* See documentation in cli-utils.h.  */

char *
skip_to_space (char *chp)
{
  if (chp == NULL)
    return NULL;
  while (*chp && !isspace (*chp))
    chp++;
  return chp;
}