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