xref: /dflybsd-src/contrib/gcc-8.0/libiberty/vprintf-support.c (revision 38fd149817dfbff97799f62fcb70be98c4e32523)
1*38fd1498Szrj /* Estimate the length of the string generated by a vprintf-like
2*38fd1498Szrj    function.  Used by vasprintf and xvasprintf.
3*38fd1498Szrj    Copyright (C) 1994-2018 Free Software Foundation, Inc.
4*38fd1498Szrj 
5*38fd1498Szrj This file is part of the libiberty library.
6*38fd1498Szrj Libiberty is free software; you can redistribute it and/or
7*38fd1498Szrj modify it under the terms of the GNU Library General Public
8*38fd1498Szrj License as published by the Free Software Foundation; either
9*38fd1498Szrj version 2 of the License, or (at your option) any later version.
10*38fd1498Szrj 
11*38fd1498Szrj Libiberty is distributed in the hope that it will be useful,
12*38fd1498Szrj but WITHOUT ANY WARRANTY; without even the implied warranty of
13*38fd1498Szrj MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14*38fd1498Szrj Library General Public License for more details.
15*38fd1498Szrj 
16*38fd1498Szrj You should have received a copy of the GNU Library General Public
17*38fd1498Szrj License along with libiberty; see the file COPYING.LIB.  If not, write
18*38fd1498Szrj to the Free Software Foundation, Inc., 51 Franklin Street - Fifth
19*38fd1498Szrj Floor, Boston, MA 02110-1301, USA.  */
20*38fd1498Szrj 
21*38fd1498Szrj #ifdef HAVE_CONFIG_H
22*38fd1498Szrj #include "config.h"
23*38fd1498Szrj #endif
24*38fd1498Szrj #include <ansidecl.h>
25*38fd1498Szrj #include <stdarg.h>
26*38fd1498Szrj #if !defined (va_copy) && defined (__va_copy)
27*38fd1498Szrj # define va_copy(d,s)  __va_copy((d),(s))
28*38fd1498Szrj #endif
29*38fd1498Szrj #include <stdio.h>
30*38fd1498Szrj #ifdef HAVE_STRING_H
31*38fd1498Szrj #include <string.h>
32*38fd1498Szrj #endif
33*38fd1498Szrj #ifdef HAVE_STDLIB_H
34*38fd1498Szrj #include <stdlib.h>
35*38fd1498Szrj #else
36*38fd1498Szrj extern unsigned long strtoul ();
37*38fd1498Szrj #endif
38*38fd1498Szrj #include "libiberty.h"
39*38fd1498Szrj 
40*38fd1498Szrj int
libiberty_vprintf_buffer_size(const char * format,va_list args)41*38fd1498Szrj libiberty_vprintf_buffer_size (const char *format, va_list args)
42*38fd1498Szrj {
43*38fd1498Szrj   const char *p = format;
44*38fd1498Szrj   /* Add one to make sure that it is never zero, which might cause malloc
45*38fd1498Szrj      to return NULL.  */
46*38fd1498Szrj   int total_width = strlen (format) + 1;
47*38fd1498Szrj   va_list ap;
48*38fd1498Szrj 
49*38fd1498Szrj #ifdef va_copy
50*38fd1498Szrj   va_copy (ap, args);
51*38fd1498Szrj #else
52*38fd1498Szrj   memcpy ((PTR) &ap, (PTR) &args, sizeof (va_list));
53*38fd1498Szrj #endif
54*38fd1498Szrj 
55*38fd1498Szrj   while (*p != '\0')
56*38fd1498Szrj     {
57*38fd1498Szrj       if (*p++ == '%')
58*38fd1498Szrj 	{
59*38fd1498Szrj 	  while (strchr ("-+ #0", *p))
60*38fd1498Szrj 	    ++p;
61*38fd1498Szrj 	  if (*p == '*')
62*38fd1498Szrj 	    {
63*38fd1498Szrj 	      ++p;
64*38fd1498Szrj 	      total_width += abs (va_arg (ap, int));
65*38fd1498Szrj 	    }
66*38fd1498Szrj 	  else
67*38fd1498Szrj 	    total_width += strtoul (p, (char **) &p, 10);
68*38fd1498Szrj 	  if (*p == '.')
69*38fd1498Szrj 	    {
70*38fd1498Szrj 	      ++p;
71*38fd1498Szrj 	      if (*p == '*')
72*38fd1498Szrj 		{
73*38fd1498Szrj 		  ++p;
74*38fd1498Szrj 		  total_width += abs (va_arg (ap, int));
75*38fd1498Szrj 		}
76*38fd1498Szrj 	      else
77*38fd1498Szrj 	      total_width += strtoul (p, (char **) &p, 10);
78*38fd1498Szrj 	    }
79*38fd1498Szrj 	  while (strchr ("hlL", *p))
80*38fd1498Szrj 	    ++p;
81*38fd1498Szrj 	  /* Should be big enough for any format specifier except %s and floats.  */
82*38fd1498Szrj 	  total_width += 30;
83*38fd1498Szrj 	  switch (*p)
84*38fd1498Szrj 	    {
85*38fd1498Szrj 	    case 'd':
86*38fd1498Szrj 	    case 'i':
87*38fd1498Szrj 	    case 'o':
88*38fd1498Szrj 	    case 'u':
89*38fd1498Szrj 	    case 'x':
90*38fd1498Szrj 	    case 'X':
91*38fd1498Szrj 	    case 'c':
92*38fd1498Szrj 	      (void) va_arg (ap, int);
93*38fd1498Szrj 	      break;
94*38fd1498Szrj 	    case 'f':
95*38fd1498Szrj 	    case 'e':
96*38fd1498Szrj 	    case 'E':
97*38fd1498Szrj 	    case 'g':
98*38fd1498Szrj 	    case 'G':
99*38fd1498Szrj 	      (void) va_arg (ap, double);
100*38fd1498Szrj 	      /* Since an ieee double can have an exponent of 307, we'll
101*38fd1498Szrj 		 make the buffer wide enough to cover the gross case. */
102*38fd1498Szrj 	      total_width += 307;
103*38fd1498Szrj 	      break;
104*38fd1498Szrj 	    case 's':
105*38fd1498Szrj 	      total_width += strlen (va_arg (ap, char *));
106*38fd1498Szrj 	      break;
107*38fd1498Szrj 	    case 'p':
108*38fd1498Szrj 	    case 'n':
109*38fd1498Szrj 	      (void) va_arg (ap, char *);
110*38fd1498Szrj 	      break;
111*38fd1498Szrj 	    }
112*38fd1498Szrj 	  p++;
113*38fd1498Szrj 	}
114*38fd1498Szrj     }
115*38fd1498Szrj #ifdef va_copy
116*38fd1498Szrj   va_end (ap);
117*38fd1498Szrj #endif
118*38fd1498Szrj   return total_width;
119*38fd1498Szrj }
120