michael@574: /* Like vsprintf but provides a pointer to malloc'd storage, which must
michael@574:    be freed by the caller.
michael@574:    Copyright (C) 1994, 2003 Free Software Foundation, Inc.
michael@574: 
michael@574: This file is part of the libiberty library.
michael@574: Libiberty is free software; you can redistribute it and/or
michael@574: modify it under the terms of the GNU Library General Public
michael@574: License as published by the Free Software Foundation; either
michael@574: version 2 of the License, or (at your option) any later version.
michael@574: 
michael@574: Libiberty is distributed in the hope that it will be useful,
michael@574: but WITHOUT ANY WARRANTY; without even the implied warranty of
michael@574: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
michael@574: Library General Public License for more details.
michael@574: 
michael@574: You should have received a copy of the GNU Library General Public
michael@574: License along with libiberty; see the file COPYING.LIB.  If
michael@574: not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
michael@574: Boston, MA 02111-1307, USA.  */
michael@574: 
michael@574: #include <stdarg.h>
michael@574: #include <stdio.h>
michael@574: #include <stdlib.h>
michael@574: #include <string.h>
michael@574: #include "vasprintf.h"
michael@574: 
michael@574: /*
michael@574: 
michael@574: @deftypefn Extension int vasprintf (char **@var{resptr}, const char *@var{format}, va_list @var{args})
michael@574: 
michael@574: Like @code{vsprintf}, but instead of passing a pointer to a buffer,
michael@574: you pass a pointer to a pointer.  This function will compute the size
michael@574: of the buffer needed, allocate memory with @code{malloc}, and store a
michael@574: pointer to the allocated memory in @code{*@var{resptr}}.  The value
michael@574: returned is the same as @code{vsprintf} would return.  If memory could
michael@574: not be allocated, minus one is returned and @code{NULL} is stored in
michael@574: @code{*@var{resptr}}.
michael@574: 
michael@574: @end deftypefn
michael@574: 
michael@574: */
michael@574: 
michael@574: static int int_vasprintf(char **, const char *, va_list);
michael@574: 
michael@574: static int
michael@574: int_vasprintf (result, format, args)
michael@574:      char **result;
michael@574:      const char *format;
michael@574:      va_list args;
michael@574: {
michael@574:   const char *p = format;
michael@574:   /* Add one to make sure that it is never zero, which might cause malloc
michael@574:      to return NULL.  */
michael@574:   int total_width = strlen (format) + 1;
michael@574:   va_list ap;
michael@574: 
michael@574:   memcpy ((void *) &ap, (const void *) &args, sizeof (va_list));
michael@574: 
michael@574:   while (*p != '\0')
michael@574:     {
michael@574:       if (*p++ == '%')
michael@574: 	{
michael@574: 	  while (strchr ("-+ #0", *p))
michael@574: 	    ++p;
michael@574: 	  if (*p == '*')
michael@574: 	    {
michael@574: 	      ++p;
michael@574: 	      total_width += abs (va_arg (ap, int));
michael@574: 	    }
michael@574: 	  else
michael@574: 	    total_width += strtoul (p, (char **) &p, 10);
michael@574: 	  if (*p == '.')
michael@574: 	    {
michael@574: 	      ++p;
michael@574: 	      if (*p == '*')
michael@574: 		{
michael@574: 		  ++p;
michael@574: 		  total_width += abs (va_arg (ap, int));
michael@574: 		}
michael@574: 	      else
michael@574: 	      total_width += strtoul (p, (char **) &p, 10);
michael@574: 	    }
michael@574: 	  while (strchr ("hlL", *p))
michael@574: 	    ++p;
michael@574: 	  /* Should be big enough for any format specifier except %s and floats.  */
michael@574: 	  total_width += 30;
michael@574: 	  switch (*p)
michael@574: 	    {
michael@574: 	    case 'd':
michael@574: 	    case 'i':
michael@574: 	    case 'o':
michael@574: 	    case 'u':
michael@574: 	    case 'x':
michael@574: 	    case 'X':
michael@574: 	    case 'c':
michael@574: 	      (void) va_arg (ap, int);
michael@574: 	      break;
michael@574: 	    case 'f':
michael@574: 	    case 'e':
michael@574: 	    case 'E':
michael@574: 	    case 'g':
michael@574: 	    case 'G':
michael@574: 	      (void) va_arg (ap, double);
michael@574: 	      /* Since an ieee double can have an exponent of 307, we'll
michael@574: 		 make the buffer wide enough to cover the gross case. */
michael@574: 	      total_width += 307;
michael@574: 	      break;
michael@574: 	    case 's':
michael@574: 	      total_width += strlen (va_arg (ap, char *));
michael@574: 	      break;
michael@574: 	    case 'p':
michael@574: 	    case 'n':
michael@574: 	      (void) va_arg (ap, char *);
michael@574: 	      break;
michael@574: 	    }
michael@574: 	  p++;
michael@574: 	}
michael@574:     }
michael@574:   *result = (char *) malloc (total_width);
michael@574:   if (*result != NULL)
michael@574:     return vsprintf (*result, format, args);
michael@574:   else
michael@574:     return -1;
michael@574: }
michael@574: 
michael@574: int
michael@574: vasprintf (result, format, args)
michael@574:      char **result;
michael@574:      const char *format;
michael@574:      va_list args;
michael@574: {
michael@574:   return int_vasprintf (result, format, args);
michael@574: }