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      1 /* Like vsprintf but provides a pointer to malloc'd storage, which must
      2    be freed by the caller.
      3    Copyright (C) 1994, 2003, 2011, 2013 Free Software Foundation, Inc.
      4 
      5 This file is part of the libiberty library.
      6 Libiberty is free software; you can redistribute it and/or
      7 modify it under the terms of the GNU Library General Public
      8 License as published by the Free Software Foundation; either
      9 version 2 of the License, or (at your option) any later version.
     10 
     11 Libiberty is distributed in the hope that it will be useful,
     12 but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14 Library General Public License for more details.
     15 
     16 You should have received a copy of the GNU Library General Public
     17 License along with libiberty; see the file COPYING.LIB.  If
     18 not, write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
     19 Boston, MA 02110-1301, USA.  */
     20 
     21 #ifdef HAVE_CONFIG_H
     22 #include "config.h"
     23 #endif
     24 #include <ansidecl.h>
     25 #include <stdarg.h>
     26 #if !defined (va_copy) && defined (__va_copy)
     27 # define va_copy(d,s)  __va_copy((d),(s))
     28 #endif
     29 #include <stdio.h>
     30 #ifdef HAVE_STRING_H
     31 #include <string.h>
     32 #endif
     33 #ifdef HAVE_STDLIB_H
     34 #include <stdlib.h>
     35 #else
     36 extern unsigned long strtoul ();
     37 extern PTR malloc ();
     38 #endif
     39 #include "libiberty.h"
     40 
     41 #ifdef TEST
     42 int global_total_width;
     43 #endif
     44 
     45 /*
     46 
     47 @deftypefn Extension int vasprintf (char **@var{resptr}, @
     48   const char *@var{format}, va_list @var{args})
     49 
     50 Like @code{vsprintf}, but instead of passing a pointer to a buffer,
     51 you pass a pointer to a pointer.  This function will compute the size
     52 of the buffer needed, allocate memory with @code{malloc}, and store a
     53 pointer to the allocated memory in @code{*@var{resptr}}.  The value
     54 returned is the same as @code{vsprintf} would return.  If memory could
     55 not be allocated, minus one is returned and @code{NULL} is stored in
     56 @code{*@var{resptr}}.
     57 
     58 @end deftypefn
     59 
     60 */
     61 
     62 static int int_vasprintf (char **, const char *, va_list);
     63 
     64 static int
     65 int_vasprintf (char **result, const char *format, va_list args)
     66 {
     67   const char *p = format;
     68   /* Add one to make sure that it is never zero, which might cause malloc
     69      to return NULL.  */
     70   int total_width = strlen (format) + 1;
     71   va_list ap;
     72 
     73 #ifdef va_copy
     74   va_copy (ap, args);
     75 #else
     76   memcpy ((PTR) &ap, (PTR) &args, sizeof (va_list));
     77 #endif
     78 
     79   while (*p != '\0')
     80     {
     81       if (*p++ == '%')
     82 	{
     83 	  while (strchr ("-+ #0", *p))
     84 	    ++p;
     85 	  if (*p == '*')
     86 	    {
     87 	      ++p;
     88 	      total_width += abs (va_arg (ap, int));
     89 	    }
     90 	  else
     91 	    total_width += strtoul (p, (char **) &p, 10);
     92 	  if (*p == '.')
     93 	    {
     94 	      ++p;
     95 	      if (*p == '*')
     96 		{
     97 		  ++p;
     98 		  total_width += abs (va_arg (ap, int));
     99 		}
    100 	      else
    101 	      total_width += strtoul (p, (char **) &p, 10);
    102 	    }
    103 	  while (strchr ("hlL", *p))
    104 	    ++p;
    105 	  /* Should be big enough for any format specifier except %s and floats.  */
    106 	  total_width += 30;
    107 	  switch (*p)
    108 	    {
    109 	    case 'd':
    110 	    case 'i':
    111 	    case 'o':
    112 	    case 'u':
    113 	    case 'x':
    114 	    case 'X':
    115 	    case 'c':
    116 	      (void) va_arg (ap, int);
    117 	      break;
    118 	    case 'f':
    119 	    case 'e':
    120 	    case 'E':
    121 	    case 'g':
    122 	    case 'G':
    123 	      (void) va_arg (ap, double);
    124 	      /* Since an ieee double can have an exponent of 307, we'll
    125 		 make the buffer wide enough to cover the gross case. */
    126 	      total_width += 307;
    127 	      break;
    128 	    case 's':
    129 	      total_width += strlen (va_arg (ap, char *));
    130 	      break;
    131 	    case 'p':
    132 	    case 'n':
    133 	      (void) va_arg (ap, char *);
    134 	      break;
    135 	    }
    136 	  p++;
    137 	}
    138     }
    139 #ifdef va_copy
    140   va_end (ap);
    141 #endif
    142 #ifdef TEST
    143   global_total_width = total_width;
    144 #endif
    145   *result = (char *) malloc (total_width);
    146   if (*result != NULL)
    147     return vsprintf (*result, format, args);
    148   else
    149     return -1;
    150 }
    151 
    152 int
    153 vasprintf (char **result, const char *format,
    154 #if defined (_BSD_VA_LIST_) && defined (__FreeBSD__)
    155            _BSD_VA_LIST_ args)
    156 #else
    157            va_list args)
    158 #endif
    159 {
    160   return int_vasprintf (result, format, args);
    161 }
    162 
    163 #ifdef TEST
    164 static void ATTRIBUTE_PRINTF_1
    165 checkit (const char *format, ...)
    166 {
    167   char *result;
    168   va_list args;
    169   va_start (args, format);
    170   vasprintf (&result, format, args);
    171   va_end (args);
    172 
    173   if (strlen (result) < (size_t) global_total_width)
    174     printf ("PASS: ");
    175   else
    176     printf ("FAIL: ");
    177   printf ("%d %s\n", global_total_width, result);
    178 
    179   free (result);
    180 }
    181 
    182 extern int main (void);
    183 
    184 int
    185 main (void)
    186 {
    187   checkit ("%d", 0x12345678);
    188   checkit ("%200d", 5);
    189   checkit ("%.300d", 6);
    190   checkit ("%100.150d", 7);
    191   checkit ("%s", "jjjjjjjjjiiiiiiiiiiiiiiioooooooooooooooooppppppppppppaa\n\
    192 777777777777777777333333333333366666666666622222222222777777777777733333");
    193   checkit ("%f%s%d%s", 1.0, "foo", 77, "asdjffffffffffffffiiiiiiiiiiixxxxx");
    194 
    195   return 0;
    196 }
    197 #endif /* TEST */
    198