xref: /dflybsd-src/contrib/binutils-2.34/libiberty/vprintf-support.c (revision b52ef7118d1621abed722c5bbbd542210290ecef)
1*fae548d3Szrj /* Estimate the length of the string generated by a vprintf-like
2*fae548d3Szrj    function.  Used by vasprintf and xvasprintf.
3*fae548d3Szrj    Copyright (C) 1994-2020 Free Software Foundation, Inc.
4*fae548d3Szrj 
5*fae548d3Szrj This file is part of the libiberty library.
6*fae548d3Szrj Libiberty is free software; you can redistribute it and/or
7*fae548d3Szrj modify it under the terms of the GNU Library General Public
8*fae548d3Szrj License as published by the Free Software Foundation; either
9*fae548d3Szrj version 2 of the License, or (at your option) any later version.
10*fae548d3Szrj 
11*fae548d3Szrj Libiberty is distributed in the hope that it will be useful,
12*fae548d3Szrj but WITHOUT ANY WARRANTY; without even the implied warranty of
13*fae548d3Szrj MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14*fae548d3Szrj Library General Public License for more details.
15*fae548d3Szrj 
16*fae548d3Szrj You should have received a copy of the GNU Library General Public
17*fae548d3Szrj License along with libiberty; see the file COPYING.LIB.  If not, write
18*fae548d3Szrj to the Free Software Foundation, Inc., 51 Franklin Street - Fifth
19*fae548d3Szrj Floor, Boston, MA 02110-1301, USA.  */
20*fae548d3Szrj 
21*fae548d3Szrj #ifdef HAVE_CONFIG_H
22*fae548d3Szrj #include "config.h"
23*fae548d3Szrj #endif
24*fae548d3Szrj #include <ansidecl.h>
25*fae548d3Szrj #include <stdarg.h>
26*fae548d3Szrj #if !defined (va_copy) && defined (__va_copy)
27*fae548d3Szrj # define va_copy(d,s)  __va_copy((d),(s))
28*fae548d3Szrj #endif
29*fae548d3Szrj #include <stdio.h>
30*fae548d3Szrj #ifdef HAVE_STRING_H
31*fae548d3Szrj #include <string.h>
32*fae548d3Szrj #endif
33*fae548d3Szrj #ifdef HAVE_STDLIB_H
34*fae548d3Szrj #include <stdlib.h>
35*fae548d3Szrj #else
36*fae548d3Szrj extern unsigned long strtoul ();
37*fae548d3Szrj #endif
38*fae548d3Szrj #include "libiberty.h"
39*fae548d3Szrj 
40*fae548d3Szrj int
libiberty_vprintf_buffer_size(const char * format,va_list args)41*fae548d3Szrj libiberty_vprintf_buffer_size (const char *format, va_list args)
42*fae548d3Szrj {
43*fae548d3Szrj   const char *p = format;
44*fae548d3Szrj   /* Add one to make sure that it is never zero, which might cause malloc
45*fae548d3Szrj      to return NULL.  */
46*fae548d3Szrj   int total_width = strlen (format) + 1;
47*fae548d3Szrj   va_list ap;
48*fae548d3Szrj 
49*fae548d3Szrj #ifdef va_copy
50*fae548d3Szrj   va_copy (ap, args);
51*fae548d3Szrj #else
52*fae548d3Szrj   memcpy ((PTR) &ap, (PTR) &args, sizeof (va_list));
53*fae548d3Szrj #endif
54*fae548d3Szrj 
55*fae548d3Szrj   while (*p != '\0')
56*fae548d3Szrj     {
57*fae548d3Szrj       if (*p++ == '%')
58*fae548d3Szrj 	{
59*fae548d3Szrj 	  while (strchr ("-+ #0", *p))
60*fae548d3Szrj 	    ++p;
61*fae548d3Szrj 	  if (*p == '*')
62*fae548d3Szrj 	    {
63*fae548d3Szrj 	      ++p;
64*fae548d3Szrj 	      total_width += abs (va_arg (ap, int));
65*fae548d3Szrj 	    }
66*fae548d3Szrj 	  else
67*fae548d3Szrj 	    total_width += strtoul (p, (char **) &p, 10);
68*fae548d3Szrj 	  if (*p == '.')
69*fae548d3Szrj 	    {
70*fae548d3Szrj 	      ++p;
71*fae548d3Szrj 	      if (*p == '*')
72*fae548d3Szrj 		{
73*fae548d3Szrj 		  ++p;
74*fae548d3Szrj 		  total_width += abs (va_arg (ap, int));
75*fae548d3Szrj 		}
76*fae548d3Szrj 	      else
77*fae548d3Szrj 	      total_width += strtoul (p, (char **) &p, 10);
78*fae548d3Szrj 	    }
79*fae548d3Szrj 	  while (strchr ("hlL", *p))
80*fae548d3Szrj 	    ++p;
81*fae548d3Szrj 	  /* Should be big enough for any format specifier except %s and floats.  */
82*fae548d3Szrj 	  total_width += 30;
83*fae548d3Szrj 	  switch (*p)
84*fae548d3Szrj 	    {
85*fae548d3Szrj 	    case 'd':
86*fae548d3Szrj 	    case 'i':
87*fae548d3Szrj 	    case 'o':
88*fae548d3Szrj 	    case 'u':
89*fae548d3Szrj 	    case 'x':
90*fae548d3Szrj 	    case 'X':
91*fae548d3Szrj 	    case 'c':
92*fae548d3Szrj 	      (void) va_arg (ap, int);
93*fae548d3Szrj 	      break;
94*fae548d3Szrj 	    case 'f':
95*fae548d3Szrj 	    case 'e':
96*fae548d3Szrj 	    case 'E':
97*fae548d3Szrj 	    case 'g':
98*fae548d3Szrj 	    case 'G':
99*fae548d3Szrj 	      (void) va_arg (ap, double);
100*fae548d3Szrj 	      /* Since an ieee double can have an exponent of 307, we'll
101*fae548d3Szrj 		 make the buffer wide enough to cover the gross case. */
102*fae548d3Szrj 	      total_width += 307;
103*fae548d3Szrj 	      break;
104*fae548d3Szrj 	    case 's':
105*fae548d3Szrj 	      total_width += strlen (va_arg (ap, char *));
106*fae548d3Szrj 	      break;
107*fae548d3Szrj 	    case 'p':
108*fae548d3Szrj 	    case 'n':
109*fae548d3Szrj 	      (void) va_arg (ap, char *);
110*fae548d3Szrj 	      break;
111*fae548d3Szrj 	    }
112*fae548d3Szrj 	  p++;
113*fae548d3Szrj 	}
114*fae548d3Szrj     }
115*fae548d3Szrj #ifdef va_copy
116*fae548d3Szrj   va_end (ap);
117*fae548d3Szrj #endif
118*fae548d3Szrj   return total_width;
119*fae548d3Szrj }
120