1/* Estimate the length of the string generated by a vprintf-like 2 function. Used by vasprintf and xvasprintf. 3 Copyright (C) 1994-2024 Free Software Foundation, Inc. 4 5This file is part of the libiberty library. 6Libiberty is free software; you can redistribute it and/or 7modify it under the terms of the GNU Library General Public 8License as published by the Free Software Foundation; either 9version 2 of the License, or (at your option) any later version. 10 11Libiberty is distributed in the hope that it will be useful, 12but WITHOUT ANY WARRANTY; without even the implied warranty of 13MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14Library General Public License for more details. 15 16You should have received a copy of the GNU Library General Public 17License along with libiberty; see the file COPYING.LIB. If not, write 18to the Free Software Foundation, Inc., 51 Franklin Street - Fifth 19Floor, 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 36extern unsigned long strtoul (); 37#endif 38#include "libiberty.h" 39 40int 41libiberty_vprintf_buffer_size (const char *format, va_list args) 42{ 43 const char *p = format; 44 /* Add one to make sure that it is never zero, which might cause malloc 45 to return NULL. */ 46 int total_width = strlen (format) + 1; 47 va_list ap; 48 49#ifdef va_copy 50 va_copy (ap, args); 51#else 52 memcpy ((void *) &ap, (void *) &args, sizeof (va_list)); 53#endif 54 55 while (*p != '\0') 56 { 57 if (*p++ == '%') 58 { 59 while (strchr ("-+ #0", *p)) 60 ++p; 61 if (*p == '*') 62 { 63 ++p; 64 total_width += abs (va_arg (ap, int)); 65 } 66 else 67 total_width += strtoul (p, (char **) &p, 10); 68 if (*p == '.') 69 { 70 ++p; 71 if (*p == '*') 72 { 73 ++p; 74 total_width += abs (va_arg (ap, int)); 75 } 76 else 77 total_width += strtoul (p, (char **) &p, 10); 78 } 79 while (strchr ("hlL", *p)) 80 ++p; 81 /* Should be big enough for any format specifier except %s and floats. */ 82 total_width += 30; 83 switch (*p) 84 { 85 case 'd': 86 case 'i': 87 case 'o': 88 case 'u': 89 case 'x': 90 case 'X': 91 case 'c': 92 (void) va_arg (ap, int); 93 break; 94 case 'f': 95 case 'e': 96 case 'E': 97 case 'g': 98 case 'G': 99 (void) va_arg (ap, double); 100 /* Since an ieee double can have an exponent of 307, we'll 101 make the buffer wide enough to cover the gross case. */ 102 total_width += 307; 103 break; 104 case 's': 105 total_width += strlen (va_arg (ap, char *)); 106 break; 107 case 'p': 108 case 'n': 109 (void) va_arg (ap, char *); 110 break; 111 } 112 p++; 113 } 114 } 115#ifdef va_copy 116 va_end (ap); 117#endif 118 return total_width; 119} 120