libiberty/vasprintf.c

   1 /* Like vsprintf but provides a pointer to malloc'd storage, which must
   2    be freed by the caller.
   3    Copyright (C) 1994, 2003 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., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #ifdef HAVE_CONFIG_H
  22 #include "config.h"
  23 #endif
  24 #include <ansidecl.h>
  25 #ifdef ANSI_PROTOTYPES
  26 #include <stdarg.h>
  27 #else
  28 #include <varargs.h>
  29 #endif
  30 #if !defined (va_copy) && defined (__va_copy)
  31 # define va_copy(d,s)  __va_copy((d),(s))
  32 #endif
  33 #include <stdio.h>
  34 #ifdef HAVE_STRING_H
  35 #include <string.h>
  36 #endif
  37 #ifdef HAVE_STDLIB_H
  38 #include <stdlib.h>
  39 #else
  40 extern unsigned long strtoul ();
  41 extern PTR malloc ();
  42 #endif
  43 #include "libiberty.h"
  44
  45 #ifdef TEST
  46 int global_total_width;
  47 #endif
  48
  49 /*
  50
  51 @deftypefn Extension int vasprintf (char **@var{resptr}, const char *@var{format}, va_list @var{args})
  52
  53 Like @code{vsprintf}, but instead of passing a pointer to a buffer,
  54 you pass a pointer to a pointer.  This function will compute the size
  55 of the buffer needed, allocate memory with @code{malloc}, and store a
  56 pointer to the allocated memory in @code{*@var{resptr}}.  The value
  57 returned is the same as @code{vsprintf} would return.  If memory could
  58 not be allocated, minus one is returned and @code{NULL} is stored in
  59 @code{*@var{resptr}}.
  60
  61 @end deftypefn
  62
  63 */
  64
  65 static int int_vasprintf PARAMS ((char **, const char *, va_list));
  66
  67 static int
  68 int_vasprintf (result, format, args)
  69      char **result;
  70      const char *format;
  71      va_list args;
  72 {
  73   const char *p = format;
  74   /* Add one to make sure that it is never zero, which might cause malloc
  75      to return NULL.  */
  76   int total_width = strlen (format) + 1;
  77   va_list ap;
  78
  79 #ifdef va_copy
  80   va_copy (ap, args);
  81 #else
  82   memcpy ((PTR) &ap, (PTR) &args, sizeof (va_list));
  83 #endif
  84
  85   while (*p != '\0')
  86     {
  87       if (*p++ == '%')
  88         {
  89           while (strchr ("-+ #0", *p))
  90             ++p;
  91           if (*p == '*')
  92             {
  93               ++p;
  94               total_width += abs (va_arg (ap, int));
  95             }
  96           else
  97             total_width += strtoul (p, (char **) &p, 10);
  98           if (*p == '.')
  99             {
 100               ++p;
 101               if (*p == '*')
 102                 {
 103                   ++p;
 104                   total_width += abs (va_arg (ap, int));
 105                 }
 106               else
 107               total_width += strtoul (p, (char **) &p, 10);
 108             }
 109           while (strchr ("hlL", *p))
 110             ++p;
 111           /* Should be big enough for any format specifier except %s and floats.  */
 112           total_width += 30;
 113           switch (*p)
 114             {
 115             case 'd':
 116             case 'i':
 117             case 'o':
 118             case 'u':
 119             case 'x':
 120             case 'X':
 121             case 'c':
 122               (void) va_arg (ap, int);
 123               break;
 124             case 'f':
 125             case 'e':
 126             case 'E':
 127             case 'g':
 128             case 'G':
 129               (void) va_arg (ap, double);
 130               /* Since an ieee double can have an exponent of 307, we'll
 131                  make the buffer wide enough to cover the gross case. */
 132               total_width += 307;
 133               break;
 134             case 's':
 135               total_width += strlen (va_arg (ap, char *));
 136               break;
 137             case 'p':
 138             case 'n':
 139               (void) va_arg (ap, char *);
 140               break;
 141             }
 142           p++;
 143         }
 144     }
 145 #ifdef va_copy
 146   va_end (ap);
 147 #endif
 148 #ifdef TEST
 149   global_total_width = total_width;
 150 #endif
 151   *result = (char *) malloc (total_width);
 152   if (*result != NULL)
 153     return vsprintf (*result, format, args);
 154   else
 155     return -1;
 156 }
 157
 158 int
 159 vasprintf (result, format, args)
 160      char **result;
 161      const char *format;
 162 #if defined (_BSD_VA_LIST_) && defined (__FreeBSD__)
 163      _BSD_VA_LIST_ args;
 164 #else
 165      va_list args;
 166 #endif
 167 {
 168   return int_vasprintf (result, format, args);
 169 }
 170
 171 #ifdef TEST
 172 static void ATTRIBUTE_PRINTF_1
 173 checkit VPARAMS ((const char *format, ...))
 174 {
 175   char *result;
 176   VA_OPEN (args, format);
 177   VA_FIXEDARG (args, const char *, format);
 178   vasprintf (&result, format, args);
 179   VA_CLOSE (args);
 180
 181   if (strlen (result) < (size_t) global_total_width)
 182     printf ("PASS: ");
 183   else
 184     printf ("FAIL: ");
 185   printf ("%d %s\n", global_total_width, result);
 186
 187   free (result);
 188 }
 189
 190 extern int main PARAMS ((void));
 191
 192 int
 193 main ()
 194 {
 195   checkit ("%d", 0x12345678);
 196   checkit ("%200d", 5);
 197   checkit ("%.300d", 6);
 198   checkit ("%100.150d", 7);
 199   checkit ("%s", "jjjjjjjjjiiiiiiiiiiiiiiioooooooooooooooooppppppppppppaa\n\
 200 777777777777777777333333333333366666666666622222222222777777777777733333");
 201   checkit ("%f%s%d%s", 1.0, "foo", 77, "asdjffffffffffffffiiiiiiiiiiixxxxx");
 202
 203   return 0;
 204 }
 205 #endif /* TEST */