1 2#ifndef HAVE_VPRINTF 3#include "choke-me: no vprintf and no snprintf" 4#endif 5 6#if defined(HAVE_STDARG_H) 7# include <stdarg.h> 8# ifndef VA_START 9# define VA_START(a, f) va_start(a, f) 10# define VA_END(a) va_end(a) 11# endif /* VA_START */ 12# define SNV_USING_STDARG_H 13 14#elif defined(HAVE_VARARGS_H) 15# include <varargs.h> 16# ifndef VA_START 17# define VA_START(a, f) va_start(a) 18# define VA_END(a) va_end(a) 19# endif /* VA_START */ 20# undef SNV_USING_STDARG_H 21 22#else 23# include "must-have-stdarg-or-varargs" 24#endif 25 26static int 27snprintf(char *str, size_t n, char const *fmt, ...) 28{ 29 va_list ap; 30 int rval; 31 32#ifdef VSPRINTF_CHARSTAR 33 char *rp; 34 VA_START(ap, fmt); 35 rp = vsprintf(str, fmt, ap); 36 VA_END(ap); 37 rval = strlen(rp); 38 39#else 40 VA_START(ap, fmt); 41 rval = vsprintf(str, fmt, ap); 42 VA_END(ap); 43#endif 44 45 if (rval > n) { 46 fprintf(stderr, "snprintf buffer overrun %d > %d\n", rval, (int)n); 47 abort(); 48 } 49 return rval; 50} 51 52static int 53vsnprintf( char *str, size_t n, char const *fmt, va_list ap ) 54{ 55#ifdef VSPRINTF_CHARSTAR 56 return (strlen(vsprintf(str, fmt, ap))); 57#else 58 return (vsprintf(str, fmt, ap)); 59#endif 60} 61